Search results for: mechanical energy density

Authors: Ashok Kumar, Shiv Brat Singh, Kalyan Kumar Ray

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There is growing awareness to design steels against fatigue damage Ferrite martensite dual-phase steels are known to exhibit favourable mechanical properties like good strength, ductility, toughness, continuous yielding, and high work hardening rate. However, dual-phase steels containing bainite as second phase are potential alternatives for ferrite martensite steels for certain applications where good fatigue property is required. Fatigue properties of dual phase steels are popularly assessed by the nature of variation of crack growth rate (da/dN) with stress intensity factor range (∆K), and the magnitude of fatigue threshold (∆Kth) for long cracks. There exists an increased emphasis to understand not only the long crack fatigue behavior but also short crack growth behavior of ferrite bainite dual phase steels. The major objective of this report is to examine the influence of microstructures on the short and long crack growth behavior of a series of developed dual-phase steels with varying amounts of bainite and. Three low carbon steels containing Nb, Cr and Mo as microalloying elements steels were selected for making ferrite-bainite dual-phase microstructures by suitable heat treatments. The heat treatment consisted of austenitizing the steel at 1100°C for 20 min, cooling at different rates in air prior to soaking these in a salt bath at 500°C for one hour, and finally quenching in water. Tensile tests were carried out on 25 mm gauge length specimens with 5 mm diameter using nominal strain rate 0.6x10⁻³ s⁻¹ at room temperature. Fatigue crack growth studies were made on a recently developed specimen configuration using a rotating bending machine. The crack growth was monitored by interrupting the test and observing the specimens under an optical microscope connected to an Image analyzer. The estimated crack lengths (a) at varying number of cycles (N) in different fatigue experiments were analyzed to obtain log da/dN vs. log °∆K curves for determining ∆Kthsc. The microstructural features of these steels have been characterized and their influence on the near threshold crack growth has been examined. This investigation, in brief, involves (i) the estimation of ∆Kthsc and (ii) the examination of the influence of microstructure on short and long crack fatigue threshold. The maximum fatigue threshold values obtained from short crack growth experiments on various specimens of dual-phase steels containing different amounts of bainite are found to increase with increasing bainite content in all the investigated steels. The variations of fatigue behavior of the selected steel samples have been explained with the consideration of varying amounts of the constituent phases and their interactions with the generated microstructures during cyclic loading. Quantitative estimation of the different types of fatigue crack paths indicates that the propensity of a crack to pass through the interfaces depends on the relative amount of the microstructural constituents. The fatigue crack path is found to be predominantly intra-granular except for the ones containing > 70% bainite in which it is predominantly inter-granular.

Keywords: bainite, dual phase steel, fatigue crack growth rate, long crack fatigue threshold, short crack fatigue threshold

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Authors: Michelann Parr

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Family-school-community engagement enhances family-school-community well-being, collective confidence, and school climate. While it is often referred to as a positive thing in the literature for families, schools, and communities, it does not come without its struggles. While there are numerous things families, schools, and communities do each and every day to enhance engagement, it is often difficult to find our way to true belonging and engagement. Working our way surface level barriers is easy; we can provide childcare, transportation, resources, and refreshments. We can even change the environment so that families will feel welcome, valued, and respected. But there are often mindsets and perpsectives buried deep below the surface, most often grounded in societal, familial, and political norms, expectations, pressures, and narratives. This work requires ongoing energy, commitment, and engagement of all stakeholders, including families, schools, and communities. Each and every day, we need to take a reflective and introspective stance at what is said and done and how it supports the overall goal of family-school-community engagement. And whatever we must occur within a paradigm of care in additional to one of critical thinking and social justice. Families, and those working with families, must not simply accept all that is given, but should instead ask these types of questions: a) How, and by whom, are the current philosophies and practices of family-school engagement interrogated? b) How might digging below surface level meanings support understanding of what is being said and done? c) How can we move toward meaningful and authentic engagement that balances knowledge and power between family, school, district, community (local and global), and government? This type of work requires conscious attention and intentional decision-making at all levels bringing us one step closer to authentic and meaningful partnerships. Strategies useful to building a growth mindset include: a) interrogating and exploring consistencies and inconsistencies by looking at what is done and what is not done through multiple perspectives; b) recognizing that enhancing family-engagement and changing mindsets take place at the micro-level (e.g., family and school), but also require active engagement and awareness at the macro-level (e.g., community agencies, district school boards, government); c) taking action as an advocate or activist. Negative narratives about families, schools, and communities should not be maintained, but instead critical and courageous conversations in and out of school should be initiated and sustained; and d) maintaining consistency, simplicity, and steady progress. All involved in engagement need to be aware of the struggles, but keep them in check with the many successes. Change may not be observed on a day-to-day basis or even immediately, but stepping back and looking from the outside in, might change the view. Working toward a growth mindset will produce better results than a fixed mindset, and this takes time.

Keywords: family engagment, family-school-community engagement, parent engagement, parent involvment

Procedia PDF Downloads 177

Authors: Woraya Som-Indra

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This article purposes to decode the notion of democracy embedded in the political speeches of Aung San Su Kyi by adopting critical discourse analysis approach, using Systemic Function Linguistics (SFL) and transitivity as a vital analytical tool. Two main objectives of the study are 1) to analyze linguistic strategies constituted the crucial characteristics of Su Kyi's political speeches by employing SFL and transitivity and 2) to examine ideology manifested the notion of democracy behind Su Kyi’s political speeches. The data consists of four speeches of Su Kyi delivering in different places within the year 2011 broadcasted through the website of US campaign for Burma. By employing linguistic tool and the concept of ideology as an analytical frame, the word choice selection found in the speeches assist explaining the manifestation of Su Kyi’s ideology toward democracy and power struggle. The finding revealed eight characters of word choice projected from Su Kyi’s political speeches, as follows; 1) support, hope and encouragement which render the recipients to uphold with the mutual aim to fight for democracy together and moving forwards for change and solution in the future, 2) aim and achievement evoke the recipients to attach with the purpose to fight for democracy, 3) challenge and change release energy to challenge the present political regime of Burma to change to the new political regime of democracy, 4) action, doing and taking signify the action and practical process to call for a new political regime, 5) struggle represents power struggle during the process of democracy requesting and it could refer to her long period of house arrest in Burma, 6) freedom implies what she has been long fighting for- to be released from house arrest, be able to access to the freedom of speech related to political ideology, and moreover, be able to speak out for the people of Burmese about their desirable political regime and political participation, 7) share and scarify call the recipients to have the spirit of shared value in the process of acquiring democracy, and 8) solution and achievement remind her recipients of what they have been long fighting for, and what could lead them to reach out the mutual achievement of a new political regime, i.e. democracy. Those word choice selections are plausible representation of democracy notion in Su Kyi’s terms. Due to her long journey of fighting for democracy in Burma, Suu Kyi’s political speeches always possess tremendously strong leadership characteristic, using words of wisdom and moreover, they are encoded with a wide range of words related to democracy ideology in order to push forward the future change into the Burma’s political regime.

Keywords: Aung San Su Kyi’s speeches, critical discourse analysis, democracy ideology, systemic function linguistics, transitivity

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Authors: Mehrnaz Mostafavi, Alireza Azani, Mahtab Shabani, Fatemeh Ghafari

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While filled with promise and wonder, space exploration also presents significant challenges, one of the foremost being the threat of cosmic radiation to astronaut health. Recent advancements in assessing these risks and developing protective strategies have shed new light on this issue. Cosmic radiation encompasses a variety of high-energy particles originating from sources like solar particle events, galactic cosmic rays, and cosmic rays from beyond the solar system. These particles, composed of protons, electrons, and heavy ions, pose a substantial threat to human health in space due to the lack of Earth's protective atmosphere and magnetic field. Researchers have made significant progress in assessing the risks associated with cosmic radiation exposure. By employing advanced dosimetry techniques and conducting biological studies, they have gained insights into how cosmic radiation affects astronauts' health, including increasing the risk of cancer and radiation sickness. This research has led to personalized risk assessment methods tailored to individual astronaut profiles. Distinctive protection strategies have been proposed to combat the dangers of cosmic radiation. These include developing spacecraft shielding materials and designs to enhance radiation protection. Additionally, researchers are exploring pharmacological interventions such as radioprotective drugs and antioxidant therapies to mitigate the biological effects of radiation exposure and preserve astronaut well-being. The findings from recent research have significant implications for the future of space exploration. By advancing our understanding of cosmic radiation risks and developing effective protection strategies, we pave the way for safer and more sustainable human missions beyond Earth's orbit. This is especially crucial for long-duration missions to destinations like Mars, where astronauts will face prolonged exposure to cosmic radiation. In conclusion, recent research has marked a milestone in addressing the challenges posed by cosmic radiation in space exploration. By delving into the complexities of cosmic radiation exposure and developing innovative protection strategies, scientists are ensuring the health and resilience of astronauts as they venture into the vast expanse of the cosmos. Continued research and collaboration in this area are essential for overcoming the cosmic radiation challenge and enabling humanity to embark on new frontiers of exploration and discovery in space.

Keywords: Space exploration, cosmic radiation, astronaut health, risk assessment, protective strategies

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Authors: Huixia Shi, Can Hu, Jun Zhu, Hongling Guo, Haiyan Li, Hongyan Du

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The identification of human body fluids during forensic investigations is a critical step to determine key details, and present strong evidence to testify criminal in a case. With the popularity of DNA and improved detection technology, the potential question must be revolved that whether the suspect’s DNA derived from saliva or semen, menstrual or peripheral blood, how to identify the red substance or aged blood traces on the spot is blood; How to determine who contribute the right one in mixed stains. In recent years, molecular approaches have been developing increasingly on mRNA, miRNA, DNA methylation and microbial markers, but appear expensive, time-consuming, and destructive disadvantages. Physicochemical methods are utilized frequently such us scanning electron microscopy/energy spectroscopy and X-ray fluorescence and so on, but results only showing one or two characteristics of body fluid itself and that out of working in unknown or mixed body fluid stains. This paper focuses on using chemistry methods Raman spectroscopy and matrix-assisted laser desorption/ionization time-of-flight mass spectrometry to discriminate species of peripheral blood, menstrual blood, semen, saliva, vaginal secretions, urine or sweat. Firstly, non-destructive, confirmatory, convenient and fast Raman spectroscopy method combined with more accurate matrix-assisted laser desorption/ionization time-of-flight mass spectrometry method can totally distinguish one from other body fluids. Secondly, 11 spectral signatures and specific metabolic molecules have been obtained by analysis results after 70 samples detected. Thirdly, Raman results showed peripheral and menstrual blood, saliva and vaginal have highly similar spectroscopic features. Advanced statistical analysis of the multiple Raman spectra must be requested to classify one to another. On the other hand, it seems that the lactic acid can differentiate peripheral and menstrual blood detected by matrix-assisted laser desorption/ionization time-of-flight mass spectrometry, but that is not a specific metabolic molecule, more sensitivity ones will be analyzed in a forward study. These results demonstrate the great potential of the developed chemistry methods for forensic applications, although more work is needed for method validation.

Keywords: body fluids, identification, Raman spectroscopy, matrix-assisted laser desorption/ionization time-of-flight mass spectrometry

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Authors: Olumuyiwa Ayoola Kokapi, Olugbenga Solomon Bello

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Dyes are organic compounds with complex aromatic molecular structure that resulted in fast colour on a substance. Dye effluent found in wastewater generated from the dyeing industries is one of the greatest contributors to water pollution. Groundnut hull (GH) is an agricultural material that constitutes waste in the environment. Environmental contamination by hazardous organic chemicals is an urgent problem, which is partially solved through adsorption technologies. The choice of groundnut hull was promised on the understanding that some materials of agricultural origin have shown potentials to act as Adsorbate for hazardous organic chemicals. The aim of this research is to evaluate the potential of groundnut hull to adsorb Crystal violet dye through kinetic, isotherm and thermodynamic studies. The prepared groundnut hulls was characterized using Brunauer, Emmett and Teller (BET), Fourier transform infrared (FTIR) and scanning electron microscopy (SEM). Operational parameters such as contact time, initial dye concentration, pH, and effect of temperature were studied. Equilibrium time for the adsorption process was attained in 80 minutes. Adsorption isotherms used to test the adsorption data were Langmuir and Freundlich isotherms model. Thermodynamic parameters such as ∆G°, ∆H°, and ∆S° of the adsorption processes were determined. The results showed that the uptake of dye by groundnut hulls occurred at a faster rate, corresponding to an increase in adsorption capacity at equilibrium time of 80 min from 0.78 to 4.45 mg/g and 0.77 to 4.45mg/g with an increase in the initial dye concentration from 10 to 50 mg/L for pH 3.0 and 8.0 respectively. High regression values obtained for pseudo-second-order kinetic model, sum of square error (SSE%) values along with strong agreement between experimental and calculated values of qe proved that pseudo second-order kinetic model fitted more than pseudo first-order kinetic model. The result of Langmuir and Freundlich model showed that the adsorption data fit the Langmuir model more than the Freundlich model. Thermodynamic study demonstrated the feasibility, spontaneous and endothermic nature of the adsorption process due to negative values of free energy change (∆G) at all temperatures and positive value of enthalpy change (∆H) respectively. The positive values of ∆S showed that there was increased disorderliness and randomness at the solid/solution interface of crystal violet dye and groundnut hulls. The present investigation showed that, groundnut hulls (GH) is a good low-cost alternative adsorbent for the removal of Crystal Violet (CV) dye from aqueous solution.

Keywords: adsorption, crystal violet dye, groundnut halls, kinetics

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Authors: Diego Abbo

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On February 15, 2012 off the Indian coast of Kerala, in position 091702N-0760180E by the oil tanker Enrica Lexie, flying the Italian flag, bursts of 5.56 x45 caliber shots were fired from assault rifles AR/70 Italian-made Beretta towards the Indian fisher boat St. Anthony. The shots that hit the St. Anthony fishing boat were six, of which two killed the Indian fishermen Ajesh Pink and Valentine Jelestine. From the analysis concerning the kinematic engagement of the two ships and from the autopsy and ballistic results of the Indian judicial authorities it is possible to reconstruct the trajectories of the six aforementioned shots. This essay reconstructs the trajectories of the six shots that cannot be of direct shooting but have undergone a rebound on the water. The investigation carried out scientifically demonstrates the rebound of the blows on the water, the gyrostatic deviation due to the rebound and the tumbling effect always due to the rebound as regards intermediate ballistics. In consideration of the four shots that directly impacted the fishing vessel, the current examination proves, with scientific value, that the trajectories could not be downwards but upwards. Also, the trajectory of two shots that hit to death the two fishermen could not be downwards but only upwards. In fact, this paper demonstrates, with scientific value: The loss of speed of the projectiles due to the rebound on the water; The tumbling effect in the ballistic medium within the two victims; The permanent cavities subject to the injury ballistics and the related ballistic trauma that prevented homeostasis causing bleeding in one case; The thermo-hardening deformation of the bullet found in Valentine Jelestine's skull; The upward and non-downward trajectories. The paper constitutes a tool in forensic ballistics in that it manages to reconstruct, from the final spot of the projectiles fired, all phases of ballistics like the internal one of the weapons that fired, the intermediate one, the terminal one and the penetrative structural one. In general terms the ballistics reconstruction is based on measurable parameters whose entity is contained with certainty within a lower and upper limit. Therefore, quantities that refer to angles, speed, impact energy and firing position of the shooter can be identified within the aforementioned limits. Finally, the investigation into the internal bullet track, obtained from any autopsy examination, offers a significant “lesson learned” but overall a starting point to contain or mitigate bleeding as a rescue from future gunshot wounds.

Keywords: impact physics, intermediate ballistics, terminal ballistics, tumbling effect

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Authors: Ali Ahmed Ali Al-Juboori, H. Zhu, D. Wexler, H. Li, C. Lu, J. McLeod, S. Pannila, J. Barnes

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A number of studies have focused on the formation mechanics of white etching layer and its origin in the railway operation. Until recently, the following hypotheses consider the precise mechanics of WELs formation: (i) WELs are the result of thermal process caused by wheel slip; (ii) WELs are mechanically induced by severe plastic deformation; (iii) WELs are caused by a combination of thermo-mechanical process. The mechanisms discussed above lead to occurrence of white etching layers on the area of wheel and rail contact. This is because the contact patch which is the active point of the wheel on the rail is exposed to highest shear stresses which result in localised severe plastic deformation; and highest rate of heat caused by wheel slipe during excessive traction or braking effort. However, if the WELs are not on the running band area, it would suggest that there is another cause of WELs formation. In railway system, particularly electrified railway, arcing phenomenon has been occurring more often and regularly on the rails. In electrified railway, the current is delivered to the train traction motor via contact wires and then returned to the station via the contact between the wheel and the rail. If the contact between the wheel and the rail is temporarily losing, due to dynamic vibration, entrapped dirt or water, lubricant effect or oxidation occurrences, high current can jump through the gap and results in arcing. The other resources of arcing also include the wheel passage the insulated joint and lightning on a train during bad weather. During the arcing, an extensive heat is generated and speared over a large area of top surface of rail. Thus, arcing is considered another heat source in the rail head (rather than wheel slipe) that results in microstructural changes and white etching layer formation. A head hardened (HH) rail steel, cut from a curved rail truck was used for the investigation. Samples were sectioned from a depth of 10 mm below the rail surface, where the material is considered to be still within the hardened layer but away from any microstructural changes on the top surface layer caused by train passage. These samples were subjected to electrical discharges by using Gas Tungsten Arc Welding (GTAW) machine. The arc current was controlled and moved along the samples surface in the direction of travel, as indicated by an arrow. Five different conditions were applied on the surface of the samples. Samples containing pre-existed WELs, taken from ex-service rail surface, were also considered in this study for comparison. Both simulated and ex-serviced WELs were characterised by advanced methods including SEM, TEM, TKD, EDS, XRD. Samples for TEM and TKFD were prepared by Focused Ion Beam (FIB) milling. The results showed that both simulated WELs by electrical arcing and ex-service WEL comprise similar microstructure. Brown etching layer was found with WELs and likely induced by a concurrent tempering process. This study provided a clear understanding of new formation mechanics of WELs which contributes to track maintenance procedure.

Keywords: white etching layer, arcing, brown etching layer, material characterisation

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Authors: Jiujie Cai, Fengxia LI, Haibo Wang

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After years of research, offshore oil and gas development now are shifted to unconventional reservoirs, where multi-stage hydraulic fracturing technology has been widely used. However, the simulation of complex hydraulic fractures in tight reservoirs is faced with geological and engineering difficulties, such as large burial depths, sand-shale interbeds, and complex stress barriers. The objective of this work is to simulate the hydraulic fracture propagation in the tight sandstone matrix of the marine-continental transitional reservoirs, where the Shanxi Formation in Tianhuan syncline of the Dongsheng gas field was used as the research target. The characteristic parameters of the vertical rock samples with rich beddings were clarified through rock mechanics experiments. The influence of rock mechanical parameters, vertical stress difference of pay-zone and bedding layer, and fracturing parameters (such as injection rates, fracturing fluid viscosity, and number of perforation clusters within single stage) on fracture initiation and propagation were investigated. In this paper, a 3-D fracture propagation model was built to investigate the complex fracture propagation morphology by boundary element method, considering the strength of bonding surface between layers, vertical stress difference and fracturing parameters (such as injection rates, fluid volume and viscosity). The research results indicate that on the condition of vertical stress difference (3 MPa), the fracture height can break through and enter the upper interlayer when the thickness of the overlying bedding layer is 6-9 m, considering effect of the weak bonding surface between layers. The fracture propagates within the pay zone when overlying interlayer is greater than 13 m. Difference in fluid volume distribution between clusters could be more than 20% when the stress difference of each cluster in the segment exceeds 2MPa. Fracture cluster in high stress zones cannot initiate when the stress difference in the segment exceeds 5MPa. The simulation results of fracture height are much higher if the effect of weak bonding surface between layers is not involved. By increasing the injection rates, increasing fracturing fluid viscosity, and reducing the number of clusters within single stage can promote the fracture height propagation through layers. Optimizing the perforation position and reducing the number of perforations can promote the uniform expansion of fractures. Typical curves of fracture height estimation were established for the tight sandstone of the Lower Permian Shanxi Formation. The model results have good consistency with micro-seismic monitoring results of hydraulic fracturing in Well 1HF.

Keywords: fracture propagation, boundary element method, fracture height, offshore oil and gas, marine-continental transitional reservoirs, rock mechanics experiment

Procedia PDF Downloads 118

Authors: Mohammad R. Jalali

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Movement of liquid with a free surface in a container is known as slosh. For instance, slosh occurs when water in a closed tank is set in motion by a free surface displacement, or when liquid natural gas in a container is vibrated by an external driving force, such as an earthquake or movement induced by transport. Slosh is also derived from resonant switching of a natural basin. During sloshing, different types of motion are produced by energy exchange between the liquid and its container. In present study, a numerical model is developed to simulate the nonlinear even harmonic oscillations of free surface sloshing of an initial disturbance to the free surface of a liquid in a closed square basin. The response of the liquid free surface is affected by amplitude and motion frequencies of its container; therefore, sloshing involves complex fluid-structure interactions. In the present study, nonlinear interaction of free surface sloshing of an initial Gaussian hump with its uneven container is predicted numerically. For this purpose, Green-Naghdi (GN) equations are applied as governing equation of fluid field to produce nonlinear second-order and higher-order wave interactions. These equations reduce the dimensions from three to two, yielding equations that can be solved efficiently. The GN approach assumes a particular flow kinematic structure in the vertical direction for shallow and deep-water problems. The fluid velocity profile is finite sum of coefficients depending on space and time multiplied by a weighting function. It should be noted that in GN theory, the flow is rotational. In this study, GN numerical simulations of initial Gaussian hump are compared with Fourier series semi-analytical solutions of the linearized shallow water equations. The comparison reveals that satisfactory agreement exists between the numerical simulation and the analytical solution of the overall free surface sloshing patterns. The resonant free surface motions driven by an initial Gaussian disturbance are obtained by Fast Fourier Transform (FFT) of the free surface elevation time history components. Numerically predicted velocity vectors and magnitude contours for the free surface patterns indicate that interaction of Gaussian hump with its container has localized effect. The result of this sloshing is applicable to the design of stable liquefied oil containers in tankers and offshore platforms.

Keywords: fluid-structure interactions, free surface sloshing, Gaussian hump, Green-Naghdi equations, numerical predictions

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Authors: K. X. Cheng, A. L. Goh, K. T. Ooi

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The effectiveness of microchannels in enhancing heat transfer has been demonstrated in the semiconductor industry. In order to tap the microscale heat transfer effects into macro geometries, overcoming the cost and technological constraints, microscale passages were created in macro geometries machined using conventional fabrication methods. A cylindrical insert was placed within a pipe, and geometrical profiles were created on the outer surface of the insert to enhance heat transfer under steady-state single-phase liquid flow conditions. However, while heat transfer coefficient values of above 10 kW/m2·K were achieved, the heat transfer enhancement was accompanied by undesirable pressure drop increment. Therefore, this study aims to address the high pressure drop issue using Constructal theory, a universal design law for both animate and inanimate systems. Two designs based on Constructal theory were developed to study the effectiveness of Constructal features in reducing the pressure drop increment as compared to parallel channels, which are commonly found in microchannel fabrication. The hydrodynamic and heat transfer performance for the Tree insert and Constructal fin (Cfin) insert were studied using experimental methods, and the underlying mechanisms were substantiated by numerical results. In technical terms, the objective is to achieve at least comparable increment in both heat transfer coefficient and pressure drop, if not higher increment in the former parameter. Results show that the Tree insert improved the heat transfer performance by more than 16 percent at low flow rates, as compared to the Tree-parallel insert. However, the heat transfer enhancement reduced to less than 5 percent at high Reynolds numbers. On the other hand, the pressure drop increment stayed almost constant at 20 percent. This suggests that the Tree insert has better heat transfer performance in the low Reynolds number region. More importantly, the Cfin insert displayed improved heat transfer performance along with favourable hydrodynamic performance, as compared to Cfinparallel insert, at all flow rates in this study. At 2 L/min, the enhancement of heat transfer was more than 30 percent, with 20 percent pressure drop increment, as compared to Cfin-parallel insert. Furthermore, comparable increment in both heat transfer coefficient and pressure drop was observed at 8 L/min. In other words, the Cfin insert successfully achieved the objective of this study. Analysis of the results suggests that bifurcation of flows is effective in reducing the increment in pressure drop relative to heat transfer enhancement. Optimising the geometries of the Constructal fins is therefore the potential future study in achieving a bigger stride in energy efficiency at much lower costs.

Keywords: constructal theory, enhanced heat transfer, microchannel, pressure drop

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Authors: Rajender Dahiya

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Investigation outcomes of major process incidents have been consistent for decades and validate that the causes and consequences are often identical. The debate remains as we continue to experience similar process incidents even with enormous development of new tools, technologies, industry standards, codes, regulations, and learning processes? The objective of this paper is to investigate the most common causes of major industrial incidents and reveal industry challenges and best practices to prevent such incidents. The author, in his current role, performs audits and inspections of a variety of high-hazard industries in North America, including petroleum refineries, chemicals, petrochemicals, manufacturing, etc. In this paper, he shares real life scenarios, examples, and case studies from high hazards operating facilities including key challenges and best practices. This case study will provide a clear understanding of the importance of near miss incident investigation. The incident was a Safe operating limit excursion. The case describes the deficiencies in management programs, the competency of employees, and the culture of the corporation that includes hazard identification and risk assessment, maintaining the integrity of safety-critical equipment, operating discipline, learning from process safety near misses, process safety competency, process safety culture, audits, and performance measurement. Failure to identify the hazards and manage the risks of highly hazardous materials and processes is one of the primary root-causes of an incident, and failure to learn from past incidents is the leading cause of the recurrence of incidents. Several investigations of major incidents discovered that each showed several warning signs before occurring, and most importantly, all were preventable. The author will discuss why preventable incidents were not prevented and review the mutual causes of learning failures from past major incidents. The leading causes of past incidents are summarized below. Management failure to identify the hazard and/or mitigate the risk of hazardous processes or materials. This process starts early in the project stage and continues throughout the life cycle of the facility. For example, a poorly done hazard study such as HAZID, PHA, or LOPA is one of the leading causes of the failure. If this step is performed correctly, then the next potential cause is. Management failure to maintain the integrity of safety critical systems and equipment. In most of the incidents, mechanical integrity of the critical equipment was not maintained, safety barriers were either bypassed, disabled, or not maintained. The third major cause is Management failure to learn and/or apply learning from the past incidents. There were several precursors before those incidents. These precursors were either ignored altogether or not taken seriously. This paper will conclude by sharing how a well-implemented operating management system, good process safety culture, and competent leaders and staff contributed to managing the risks to prevent major incidents.

Keywords: incident investigation, risk management, loss prevention, process safety, accident prevention

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Authors: Blessings Masuku

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This study positions itself within the nascent of street food vending that plays a crucial role in addressing urban household food security across the urban landscape of South Africa. The study aimed to understand how various forms of infrastructure systems (i.e., energy, water and sanitation, housing, and transport, among others) intersect with food and urban informality and how vendors and households’ choices and decisions made around food are influenced by infrastructure assemblages. This study noted that most of the literature studies on food security have mainly focused on the rural agricultural sector, with limited attention to urban food security, notably the role of informality practices in addressing urban food insecurity at the household level. This study pays close attention to how informal informality practices such as street food vending can be used as a catalyst to address urban poverty and household food security and steer local economies for sustainable livelihoods of the urban poor who live in the periphery of the city in Johannesburg. This study deconstructs the infrastructure needs of street food vendors, and the aim was to understand how such infrastructure needs intersect with food and policy that governs urban informality practices. The study argues that the decisions and choices of informality actors in the city of Johannesburg are chiefly determined by the assemblages of infrastructure, including regulatory frameworks that govern the informal sector in the city of Johannesburg. A qualitative approach that includes surveys (open-ended questions), archival research (i., e policy and other key document reviews), and key interviews mainly with city officials and informality actors. A thematic analysis was used to analyze the data collected. This study contributes to greater debates on urban studies and burgeoning literature on urban food security in many ways that include Firstly, the pivotal role that the informal food sector, notably street food vending, plays within the urban economy to address urban poverty and household food security, therefore questioning the conservative perspectives that view the informal sector as a hindrance to a ‘modern city’ and an annoyance to ‘modern’ urban spaces. Secondly, this study contributes to the livelihood and coping strategies of the urban poor who, despite harsh and restrictive regulatory frameworks, devise various agentive ways to generate incomes and address urban poverty and food insecurities.

Keywords: urban food security, street food vending, informal food sector, infrastructure systems, livelihood strategies, policy framework and governance

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Authors: H. Shahid

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Due to Ozone layer depletion on earth, the incoming ultraviolet (UV) radiation is recorded at its high index levels such as 25 in South Peru (13.5° S, 3360 m a.s.l.) Also, the planning of human inhabitation on Mars is under discussion where UV radiations are quite high. The exposure to UV is health hazardous and is avoided by UV filters. On the other hand, artificial UV sources are in use for water thermolysis to generate Hydrogen and Oxygen, which are later used as fuels. This paper presents the utility of employing UVA (315-400nm) and UVB (280-315nm) electromagnetic radiation from the solar spectrum to design and implement an optically active, Hydrogen and Oxygen generation system via thermolysis of desalinated seawater. The proposed system finds its utility on earth and can be deployed in the future on Mars (UVB). In this system, by using Fresnel lens arrays as an optical filter and via active tracking, the ultraviolet light from the sun is concentrated and then allowed to fall on two sub-systems of the proposed system. The first sub-system generates electrical energy by using UV based tandem photovoltaic cells such as GaAs/GaInP/GaInAs/GaInAsP and the second elevates temperature of water to lower the electric potential required to electrolyze the water. An empirical analysis is performed at 30 atm and an electrical potential is observed to be the main controlling factor for the rate of production of Hydrogen and Oxygen and hence the operating point (Q-Point) of the proposed system. The hydrogen production rate in the case of the commercial system in static mode (650ᵒC, 0.6V) is taken as a reference. The silicon oxide electrolyzer cell (SOEC) is used in the proposed (UV) system for the Hydrogen and Oxygen production. To achieve the same amount of Hydrogen as in the case of the reference system, with minimum chamber operating temperature of 850ᵒC in static mode, the corresponding required electrical potential is calculated as 0.3V. However, practically, the Hydrogen production rate is observed to be low in comparison to the reference system at 850ᵒC at 0.3V. However, it has been shown empirically that the Hydrogen production can be enhanced and by raising the electrical potential to 0.45V. It increases the production rate to the same level as is of the reference system. Therefore, 850ᵒC and 0.45V are assigned as the Q-point of the proposed system which is actively stabilized via proportional integral derivative controllers which adjust the axial position of the lens arrays for both subsystems. The functionality of the controllers is based on maintaining the chamber fixed at 850ᵒC (minimum operating temperature) and 0.45V; Q-Point to realize the same Hydrogen production rate as-is for the reference system.

Keywords: hydrogen, oxygen, thermolysis, ultraviolet

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Authors: Ivan Ashif Ardhana, Intan Mahanani

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Chemistry education tends to change from triplet representation among macroscopic, microscopic, and symbolic to tetrahedron shape. This change set the aspect of human element on the top of learning. Meaning that students are expected to solve the problems involving the ethic, morality, and humanity through the class. Ability to solve the problems connecting either theories or applications is called scientific literacy which have been implemented in curriculum 2013 implicitly. Scientific literacy has an aspect of nature science and critical thinking. Both can be integrated to learning using scientific approach and scientific inquiry. Unfortunately, students’ ability of scientific literacy in Indonesia is far from expectation. A survey from PISA had proven it. Scientific literacy of Indonesian students is always at bottom five position from 2002 till 2012. Improving a scientific literacy needs many efforts against them. Developing an instructional material based on scientific approach is one kind of that efforts. Instructional material contains both aspect of nature of science and critical thinking which is instructed explicitly to improve the students’ understanding about science. Developing goal is to produce a prototype and an instructional material using scientific approach whose chapter is chemical bonding and intermolecular forces for high school students grade ten. As usual, the material is subjected to get either quantitative mark or suggestion through validation process using validation sheet instrument. Development model is adapted from 4D model containing four steps. They are define, design, develop, and disseminate. Nevertheless, development of instructional material had only done until third step. The final step wasn’t done because of time, cost, and energy limitations. Developed instructional material had been validated by four validators. They are coming from chemistry lecture and high school’s teacher which two at each. The result of this development research shown the average of quantitative mark of students’ book is 92.75% with very proper in criteria. Given at same validation process, teacher’s guiding book got the average mark by 96.98%, similar criteria with students’ book. Qualitative mark including both comments and suggestions resulted from validation process were used as consideration for the revision. The result concluded us how the instructional materials using scientific approach to explicit nature of science and critical thinking on the topic of chemical bonding and intermolecular forces are very proper if they are used at learning activity.

Keywords: critical thinking, instructional material, nature of science, scientific literacy

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Authors: Chen Jin

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This topic seeks to re-examine the New Women Incident in 1935 Shanghai from the perspective of the influence of leftist cinematic aesthetics on public discourse in 1930s Shanghai. Accordingly, an original means of interpreting the death of Ruan Lingyu will be provided. On 8th March 1935, Ruan Lingyu, the queen of Chinese silent film, committed suicide through overdosing on sleeping tablets. Her last words, ‘gossip is fearful thing’, interlinks her destiny with the protagonist she played in the film The New Women (Cai Chusheng, 1935). The coincidence was constantly questioned by the masses following her suicide, constituting the enduring question: ‘who killed Ruan Lingyu?’ Responding to this query, previous scholars primarily analyze the characters played by women -particularly new women as part of the leftist movement or public discourse of 1930s Shanghai- as a means of approaching the truth. Nevertheless, alongside her status as a public celebrity, Ruan Lingyu also plays as a screen image of mechanical reproduction. The overlap between her screen image and personal destiny attracts limited academic focus in terms of the effect and implications of leftist aesthetics of reality in relation to her death, which itself has provided impetus to this research. With the reconfiguration of early Chinese film theory in the 1980s, early discourses on the relationship between cinematic reality and consciousness proposed by Hou Yao and Gu Kenfu in the 1920s are integrated into the category of Chinese film ontology, which constitutes a transcultural contrast with the Euro-American ontology that advocates the representation of reality. The discussion of Hou and Gu overlaps cinematic reality with effect, which emphasizes the empathy of cinema that is directly reflected in the leftist aesthetics of the 1930s. As the main purpose of leftist cinema is to encourage revolution through depicting social reality truly, Ruan Lingyu became renowned for her natural and realistic acting proficiency, playing leading roles in several esteemed leftist films. The realistic reproduction and natural acting skill together constitute the empathy of leftist films, which establishes a dialogue with the virtuous female image within the 1930s public discourse. On this basis, this research considers Chinese cinematic ontology and affect theory as the theoretical foundation for investigating the relationship between the screen image of Ruan Lingyu reproduced by the leftist film The New Women and the female image in the 1930s public discourse. Through contextualizing Ruan Lingyu’s death within the Chinese leftist movement, the essay indicates that the empathy embodied within leftist cinematic reality limits viewers’ cognition of the actress, who project their sentiments for the perfect screen image on to Ruan Lingyu’s image in reality. Essentially, Ruan Lingyu is imprisoned in her own perfect replication. Consequently, this article states that alongside leftist anti-female consciousness, the leftist aesthetics of reality restricts women in a passive position within public discourse, which ultimately plays a role in facilitating the death of Ruan Lingyu.

Keywords: cinematic reality, leftist aesthetics, Ruan Lingyu, The New Women

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Authors: Ghazala Anjum, Farooq Hussain Bhat, Ravi Kumar

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Multiferroic materials are vital for new application and memory devices, not only because of the presence of multiple types of domains but also as a result of cross correlation between coexisting forms of magnetic and electrical orders. In spite of wide studies done on multiferroic bulk ceramic materials their realization in thin film form is yet limited due to some crucial problems. During the last few years, special attention has been devoted to synthesis of thin films like of BiFeO₃. As they allow direct integration of the material into the device technology. Therefore owing to the process of exploration of new multiferroic thin films, preparation, and characterization of La₀.₈Bi₀.₂Fe₀.₇Mn₀.₃O₃ (LBFMO3) thin film on LaAlO₃ (LAO) substrate with LaNiO₃ (LNO) being the buffer layer has been done. The fact that all the electrical and magnetic properties are closely related to the electronic structure makes it inevitable to study the electronic structure of system under study. Without the knowledge of this, one may never be sure about the mechanism responsible for different properties exhibited by the thin film. Literature review reveals that studies on change in atomic and the hybridization state in multiferroic samples are still insufficient except few. The technique of x-ray absorption (XAS) has made great strides towards the goal of providing such information. It turns out to be a unique signature to a given material. In this milieu, it is time honoured to have the electronic structure study of the elements present in the LBFMO₃ multiferroic thin film on LAO substrate with buffer layer of LNO synthesized by RF sputtering technique. We report the electronic structure studies of well characterized LBFMO3 multiferroic thin film on LAO substrate with LNO as buffer layer using near-edge X-ray absorption fine structure (NEXAFS). Present exploration has been performed to find out the valence state and crystal field symmetry of ions present in the system. NEXAFS data of O K- edge spectra reveals a slight shift in peak position along with growth in intensities of low energy feature. Studies of Mn L₃,₂- edge spectra indicates the presence of Mn³⁺/Mn⁴⁺ network apart from very small contribution from Mn²⁺ ions in the system that substantiates the magnetic properties exhibited by the thin film. Fe L₃,₂- edge spectra along with spectra of reference compound reveals that Fe ions are present in +3 state. Electronic structure and valence state are found to be in accordance with the magnetic properties exhibited by LBFMO/LNO/LAO thin film.

Keywords: magnetic, multiferroic, NEXAFS, x-ray absorption fine structure, XMCD, x-ray magnetic circular dichroism

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Authors: Anthony Coogan

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Born’s probability interpretation of wave functions would have led to nearly identical results had he chosen a frequency interpretation instead. Logically, Born may have assumed that only one electron was under consideration, making it nonsensical to propose a frequency wave. Author’s suggestion: the actual experimental results were not of a single electron; rather, they were groups of reflected x-ray photons. The vertical waveform used by Scrhödinger in his Particle in the Box Theory makes sense if it was intended to represent a quantum leap. The author extended the single vertical panel to form a bar chart: separate panels would represent different energy levels. The proposed bar chart would be populated by reflected photons. Expansion of basic ideas: Part of Scrhödinger’s ‘Particle in the Box’ theory may be valid despite negative criticism. The waveform used in the diagram is vertical, which may seem absurd because real waves decay at a measurable rate, rather than instantaneously. However, there may be one notable exception. Supposedly, following from the theory, the Uncertainty Principle was derived – may a Quantum Leap not be represented as an instantaneous waveform? The great Scrhödinger must have had some reason to suggest a vertical waveform if the prevalent belief was that they did not exist. Complex wave forms representing a particle are usually assumed to be continuous. The actual observations made were x-ray photons, some of which had struck an electron, been reflected, and then moved toward a detector. From Born’s perspective, doing similar work the years in question 1926-7, he would also have considered a single electron – leading him to choose a probability distribution. Probability Distributions appear very similar to Frequency Distributions, but the former are considered to represent the likelihood of future events. Born’s interpretation of the results of quantum experiments led (or perhaps misled) many researchers into claiming that humans can influence events just by looking at them, e.g. collapsing complex wave functions by 'looking at the electron to see which slit it emerged from', while in reality light reflected from the electron moved in the observer’s direction after the electron had moved away. Astronomers may say that they 'look out into the universe' but are actually using logic opposed to the views of Newton and Hooke and many observers such as Romer, in that light carries information from a source or reflector to an observer, rather the reverse. Conclusion: Due to the controversial nature of these ideas, especially its implications about the nature of complex numbers used in applications in science and engineering, some time may pass before any consensus is reached.

Keywords: complex wave functions not necessary, frequency distributions instead of wave functions, information carried by light, sketch graph of uncertainty principle

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Authors: Kumar Divyendra

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Underwater Sensor Networks (UWSNs) have wide applications in areas such as water quality monitoring, marine wildlife management etc. A typical UWSN system consists of a set of sensors deployed randomly underwater which communicate with each other using acoustic links. RF communication doesn't work underwater, and GPS too isn't available underwater. Additionally Automated Underwater Vehicles (AUVs) are deployed to collect data from some special nodes called Cluster Heads (CHs). These CHs aggregate data from their neighboring nodes and forward them to the AUVs using optical links when an AUV is in range. This helps reduce the number of hops covered by data packets and helps conserve energy. We consider the three-dimensional model of the UWSN. Nodes are initially deployed randomly underwater. They attach themselves to the surface using a rod and can only move upwards or downwards using a pump and bladder mechanism. We use graph theory concepts to maximize the coverage volume while every node maintaining connectivity with at least one surface node. We treat the surface nodes as landmarks and each node finds out its hop distance from every surface node. We treat these hop-distances as coordinates and use them for AUV navigation. An AUV intending to move closer to a node with given coordinates moves hop by hop through nodes that are closest to it in terms of these coordinates. In absence of GPS, multiple different approaches like Inertial Navigation System (INS), Doppler Velocity Log (DVL), computer vision-based navigation, etc., have been proposed. These systems have their own drawbacks. INS accumulates error with time, vision techniques require prior information about the environment. We propose a method that makes use of the earth's magnetic field values for navigation and combines it with other methods that simultaneously increase the coverage volume under the UWSN. The AUVs are fitted with magnetometers that measure the magnetic intensity (I), horizontal inclination (H), and Declination (D). The International Geomagnetic Reference Field (IGRF) is a mathematical model of the earth's magnetic field, which provides the field values for the geographical coordinateson earth. Researchers have developed an inverse deep learning model that takes the magnetic field values and predicts the location coordinates. We make use of this model within our work. We combine this with with the hop-by-hop movement described earlier so that the AUVs move in such a sequence that the deep learning predictor gets trained as quickly and precisely as possible We run simulations in MATLAB to prove the effectiveness of our model with respect to other methods described in the literature.

Keywords: clustering, deep learning, network backbone, parallel computing

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Authors: Syahrir Andi Mangga

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During 1989–1993, the Geological Research and Development Center (recent Geological Survey Institute) Geological Agency, Ministry of Energy and Mineral Resources Republic of Indonesia was the collaboration with British Geological Survey, the United Kingdom to do technical assistance in order to collect data of geology in Sumatra Island. The overall corporation of technical programs was larger concern in stratigraphy, geochemical and age-dating studies. Availability of new data has been stimulated to reassessment of tectonic evolution of Sumatra Island. The study area located in Southern Sumatra within at latitudes 0°-6° S and 99°40’-106’00 E longitudes. The study tectonic is situated within along South Western margin of Sunda land, The Southeast Asia Continental extension arc of the Eurasian Plate and formed as part of Sunda Arc. The oceanic crust of Indian-Australian plate recently is being oblique subduction along the Sunda Trench off the West coast Sumatra. The Mesozoic-Cenozoic of the volcanic and granitic rocks can be divided into northern and southern plutons, defining a series subparallel, controlled by fault, northwest-southeast trending belts, some of the plutons are deformed and under-formed. They are widely exposed along the south-eastern side of the Barisan mountain. Based on the characteristic of minerals and crystallography, rocks found in this study area were granite, granitic, monzogranite and andesitic-Basaltic Volcanic Rock. It belongs to calc Alkaline was predominantly metalumina, I-Type Granite, Volcanic arc granites, Syncollisonal Granites (Syn_COLG) and tholeiitic basalt. It was formed since 169±5 to 20±1 Ma. The origin of magmas in interpreted to be derived from partial melting of igneous rock. The occurrence of the gratoid and volcanic rocks supposed to be closely related to the subduction of the Australian-Hindia oceanic crust beneath the Eurasia/Sunda land Continental Crust as Volcanic arc or continental margin granitic and shown youngest to the southwest. The subduction process having probably been different in position between one terrane to others led to the occurrence of segmentation subduction system. The positional discontinuities of the subduction are probably caused by the difference in time of emplacement and mechanism of volcanic and granitic rock between segments.

Keywords: tectonic setting, I-type granitic, subduction, Southern Sumatra

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Authors: Medhat Tawfik, Ezzat Abd El Lateef, Bahr Amany, Mohamed Magda

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Applying organic farming systems in biosaline agriculture is unconventional approach for sustainable use of marginal soil and desert land for planting non-traditional halophytic crops such as Leptochloa fusca, Kochia indica, Sporobolus virginicus and Spartina patens. These plants are highly salt tolerant C4 halophytic forage plants grown well in coastal salt marsh. These halophytic plant will take important place in the farming system, especially in the coastal areas and salt-affected land. We can call it environmentally smart crops because they ensure food security, contribute to energy security, guarantee environmental sustainability, and mitigate the negative impacts of climate change. Organic Agriculture is the most important and widely practiced agro-ecological farming system. It is claimed to be the most sustainable approach and long term adaptation strategy. It promotes soil fertility and diversity at all levels and makes soils less susceptible to erosion. It is also reported to be climate change resilience farming systems as it promotes the proper management of soil, water, biodiversity and local knowledge and provides producers with ecologically sound management decisions. A field experiment was carried out at the Model Farm of National Research Centre, El Tour, South Sinai to study the impact of (Mycorrhiza 1kg/fed., charcoal 4 tons/fed., chicken manure 5 tons/fed., in addition to control treatment) on some growth characters, photosynthetic pigments content, and some physiological aspects i.e. prolind and soluble carbohydrates content, succulence and osmotic pressure values, as well as nutritive values i.e. Crude fat (CF), Acid detergent fiber (ADF), Neutral detergent fiber (NDF), Ether extract (EE) and Nitrogen-free extract (NFE) of five halophytic plant species (Leptochloa fusca, Kochia indica, Sporobolus virginicus and Spartina patens). Our results showed that organic fertilizer treatment enhanced all the previous character as compared with control with superiority to chicken manure over the other treatments.

Keywords: organic agriculture, halophytic plants, saline environment, water security

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Authors: Emma Castiglioni, Nigel Scrutton, Derren Heyes, Alistair Fielding

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By using light as trigger, it is possible to study many biological processes, such as the activity of genes, proteins, and other molecules, with precise spatiotemporal control. Caged compounds, where biologically active molecules are generated from an inert precursor upon laser photolysis, offer the potential to initiate such biological reactions with high temporal resolution. As light acts as the trigger for cleaving the protecting group, the ‘caging’ technique provides a number of advantages as it can be intracellular, rapid and controlled in a quantitative manner. We are developing caging strategies to study the catalytic cycle of a number of enzyme systems, such as nitric oxide synthase and ethanolamine ammonia lyase. These include the use of caged substrates, caged electrons and the possibility of caging the enzyme itself. In addition, we are developing a novel freeze-quench instrument to study these reactions, which combines rapid mixing and flashing capabilities. Reaction intermediates will be trapped at low temperatures and will be analysed by using electron paramagnetic resonance (EPR) spectroscopy to identify the involvement of any radical species during catalysis. EPR techniques typically require relatively long measurement times and very often, low temperatures to fully characterise these short-lived species. Therefore, common rapid mixing techniques, such as stopped-flow or quench-flow are not directly suitable. However, the combination of rapid freeze-quench (RFQ) followed by EPR analysis provides the ideal approach to kinetically trap and spectroscopically characterise these transient radical species. In a typical RFQ experiment, two reagent solutions are delivered to the mixer via two syringes driven by a pneumatic actuator or stepper motor. The new mixed solution is then sprayed into a cryogenic liquid or surface, and the frozen sample is then collected and packed into an EPR tube for analysis. The earliest RFQ instrument consisted of a hydraulic ram unit as a drive unit with direct spraying of the sample into a cryogenic liquid (nitrogen, isopentane or petroleum). Improvements to the RFQ technique have arisen from the design of new mixers in order to reduce both the volume and the mixing time. In addition, the cryogenic isopentane bath has been coupled to a filtering system or replaced by spraying the solution onto a surface that is frozen via thermal conductivity with a cryogenic liquid. In our work, we are developing a novel RFQ instrument which combines the freeze-quench technology with flashing capabilities to enable the studies of both thermally-activated and light-activated biological reactions. This instrument also uses a new rotating plate design based on magnetic couplings and removes the need for mechanical motorised rotation, which can otherwise be problematic at cryogenic temperatures.

Keywords: caged compounds, freeze-quench apparatus, photolysis, radicals

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Authors: H. Scholz, P. Kuehne, G. Heckenberger

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Dietary Anion-Cation Balance (DCAB) in grazing systems under German conditions has a tendency to decrease from May until September and often are measured DCAB lower than 100 meq per kg dry matter. Lower DCAB in grass feeding system can change the metabolic status of suckler cows and often are results in acidotic metabolism. Measurement of acid-base excretion in dairy cows has been proved to a method to evaluate the acid-base status. The hypothesis was that metabolic imbalances could be identified by urine measurement in suckler cows. The farm study was conducted during the grazing seasons 2017 and 2018 and involved 7 suckler cow farms in Germany. Suckler cows were grazing during the whole time of the investigation and had no access to other feeding components. Cows had free access to water and salt block and free access to minerals (loose). The dry matter of the grass was determined at 60 °C and were then analysed for energy and nutrient content and for the Dietary Cation-Anion Balance (DCAB). Urine was collected in 50 ml-glasses and analysed for net acid-base excretion (NSBA) and the concentration of creatinine and urea in the laboratory. Statistical analysis took place with ANOVA with fixed effects of farms (1-7), month (May until September), and number of lactations (1, 2, and ≥ 3 lactations) using SPSS Version 25.0 for windows. An alpha of 0.05 was used for all statistical tests. During the grazing periods of years 2017 and 2018, an average DCAB was observed in the grass of 167 meq per kg DM. A very high mean variation could be determined from -42 meq/kg to +439 meq/kg. Reference values in relation to DCAB were described between 150 meq and 400 meq per kg DM. It was found the high chlorine content with reduced potassium level led to this reduction in DCAB at the end of the grazing period. Between the DCAB of the grass and the NSBA in urine of suckler cows was a correlation according to PEARSON of r = 0.478 (p ≤ 0.001) or after SPEARMAN of r = 0.601 (p ≤ 0.001) observed. For the control of urine values of grazing suckler cows, the wide spread of the values poses a challenge of the interpretation, especially since the DCAB is unknown. The influence of several feeding components such as chlorine, sulfur, potassium, and sodium (ions for the DCAB) and dry matter feed intake during the grazing period of suckler cows should be taken into account in further research. The results obtained show that up a decrease in the DCAB is related to a decrease in NSBA in urine of suckler cows. Monitoring of metabolic disturbances should include analysis of urine, blood, milk, and ruminal fluid.

Keywords: dietary anion-cation balance, DCAB, net acid-base excretion, NSBA, suckler cow, grazing period

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Authors: Icaro V. Soares, Guilherme L. F. Brandao, Ursula D. C. Resende, Glaucio L. Siqueira

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Electrical energy can be wirelessly transmitted through resonant coupled coils that operate in the near-field region. Once in this region, the field has evanescent character, the efficiency of Resonant Wireless Power Transfer (RWPT) systems decreases proportionally with the inverse cube of distance between the transmitter and receiver coils. The commercially available RWPT systems are restricted to short and mid-range applications in which the distance between coils is lesser or equal to the coil size. An alternative to overcome this limitation is applying metamaterial structures to enhance the coupling between coils, thus reducing the field decay along the distance between them. Metamaterials can be conceived as composite materials with periodic or non-periodic structure whose unconventional electromagnetic behaviour is due to its unit cell disposition and chemical composition. This new kind of material has been used in frequency selective surfaces, invisibility cloaks, leaky-wave antennas, among other applications. However, for RWPT it is mainly applied as superlenses which are lenses that can overcome the optical limitation and are made of left-handed media, that is, a medium with negative magnetic permeability and electric permittivity. As RWPT systems usually operate at wavelengths of hundreds of meters, the metamaterial unit cell size is much smaller than the wavelength. In this case, electric and magnetic field are decoupled, therefore the double negative condition for superlenses are not required and the negative magnetic permeability is enough to produce an artificial magnetic medium. In this work, the influence of the magnetic permeability of a metamaterial slab inserted between two loosely coupled coils is studied in order to find the condition that leads to the maximum transmission efficiency. The metamaterial used is formed by a subwavelength unit cell that consist of a capacitor-loaded split ring with an inner spiral that is designed and optimized using the software Computer Simulation Technology. The unit cell permeability is experimentally characterized by the ratio of the transmission parameters between coils measured with and without the presence of the metamaterial slab. Early measurements results show that the transmission coefficient at the resonant frequency after the inclusion of the metamaterial is about three times higher than with just the two coils, which confirms the enhancement that this structure brings to RWPT systems.

Keywords: electromagnetic lens, loosely coupled coils, magnetic permeability, metamaterials, resonant wireless power transfer, subwavelength unit cells

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Authors: Raj Chavan

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At present, the United States is home to more than 14,000 Water Resource Recovery Facilities (WRRFs), of which approximately 35% have implemented nutrient limits of some kind. These WRRFs contribute 10 to 15% of the total nutrient burden to surface rivers in the United States and account for approximately 1% of total power demand and 2% of total greenhouse gas emissions (GHG). There are several factors that have influenced the development of densification technologies in the direction of more compact and energy-efficient nutrient removal processes. Prior to surface water discharge, existing facilities that necessitate capacity expansion or biomass densification for greater treatability within the same footprint are being subjected to stricter nutrient removal requirements. Densification of activated sludge as a method for nutrient removal and process intensification at WRRFs has garnered considerable attention in recent times. The biological processes take place within the aerobic sediment granules, which form the basis of the technology. The possibility of generating granular sludge through continuous (or conventional) activated sludge processes (CAS) or densification of biomass through the transfer of activated sludge flocs to a denser biomass aggregate as an exceptionally efficient intensification technique has generated considerable interest. This presentation aims to furnish attendees with a foundational comprehension of densification through the illustration of practical concerns and insights. The subsequent subjects will be deliberated upon. What are some potential techniques for producing and preserving densified granules? What processes are responsible for the densification of biological flocs? How do physical selectors contribute to the process of biological flocs becoming denser? What viable strategies exist for the management of densified biological flocs, and which design parameters of physical selection influence the retention of densified biological flocs? determining operational solutions for floc and granule customization in order to meet capacity and performance objectives? The answers to these pivotal questions will be derived from existing full-scale treatment facilities, bench-scale and pilot-scale investigations, and existing literature data. By the conclusion of the presentation, the audience will possess a fundamental comprehension of the densification concept and its significance in attaining effective effluent treatment. Additionally, case studies pertaining to the design and operation of densification procedures will be incorporated into the presentation.

Keywords: densification, intensification, nutrient removal, granular sludge

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Authors: Syue-Wen Lin

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Objective: This article explores the nursing experience of an 84-year-old male lung cancer patient who underwent a thoracoscopic right lower lobectomy and treatment. The patient has multiple medical histories, including hypertension and diabetes. The nursing process involved cancer treatment, postoperative pain management, as well as wound care and healing. Methods: The nursing period is from February 10 to February 17, 2024. During the nursing process, pain management strategies are implemented, including morphine drugs and non-drug methods, and music therapy, essential oil massage, and extended reception time are used to make patients feel physically and mentally comfortable so as to reduce postoperative pain and encourage active participation in rehabilitation. Strict sterile wound dressing procedures and advanced wound care techniques are used to promote wound healing and prevent infection. Due to septic shock, dialysis is used to relieve worsening symptoms. Taking into account the patient's cancer status, the nursing team provides comprehensive cancer care based on the patient's physical and psychological needs. Given the complexity of the patient's condition, including advanced cancer, palliative care is also incorporated throughout the care process to relieve discomfort and provide psychological support. Results: Through comprehensive health assessment, the nursing team fully understood the patient's condition and developed a personalized care plan based on the patient's condition. The interprofessional critical care team provides respiratory therapy and lung expansion exercises to reduce muscle loss while addressing the patient's psychological status, pain management, and vital sign stabilization needs, resulting in a comprehensive approach to care. Lung expansion exercises and the use of a high-frequency chest wall oscillation vest successfully improved sputum drainage and facilitated weaning from mechanical ventilation. In addition, helping patients stabilize their vital signs and the integration of cancer care, pain management, wound care and palliative care helps the patient be fully supported throughout the recovery process, ultimately improving his quality of life. Conclusion: Lung cancer and septic shock present significant challenges to patients, and the nursing team not only provides critical care but also addresses the unique needs of patients through comprehensive infection control, cancer care, pain management, wound care, and palliative care interventions. These measures effectively improve patients' quality of life, promote recovery, and provide compassionate palliative care for terminally ill patients. Nursing staff work closely with family members to develop a comprehensive care plan to ensure that patients receive high-quality medical care as well as psychological support and a comfortable recovery environment.

Keywords: septic shock, lung cancer, palliative care, nursing experience

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Authors: Zarina Chokparova, Ighor Uzhinsky

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Carbon dioxide emissions resulting from burning of the fossil fuels on large scales, such as oil industry or power plants, leads to a plenty of severe implications including global temperature raise, air pollution and other adverse impacts on the environment. Besides some precarious and costly ways for the alleviation of CO₂ emissions detriment in industrial scales (such as liquefaction of CO₂ and its deep-water treatment, application of adsorbents and membranes, which require careful consideration of drawback effects and their mitigation), one physically and commercially available technology for its capture and disposal is supersonic system for inertial extraction of CO₂ in after-combustion streams. Due to the flue gas with a carbon dioxide concentration of 10-15 volume percent being emitted from the combustion system, the waste stream represents a rather diluted condition at low pressure. The supersonic system induces a flue gas mixture stream to expand using a converge-and-diverge operating nozzle; the flow velocity increases to the supersonic ranges resulting in rapid drop of temperature and pressure. Thus, conversion of potential energy into the kinetic power causes a desublimation of CO₂. Solidified carbon dioxide can be sent to the separate vessel for further disposal. The major advantages of the current solution are its economic efficiency, physical stability, and compactness of the system, as well as needlessness of addition any chemical media. However, there are several challenges yet to be regarded to optimize the system: the way for increasing the size of separated CO₂ particles (as they are represented on a micrometers scale of effective diameter), reduction of the concomitant gas separated together with carbon dioxide and provision of CO₂ downstream flow purity. Moreover, determination of thermodynamic conditions of the vapor-solid mixture including specification of the valid and accurate equation of state remains to be an essential goal. Due to high speeds and temperatures reached during the process, the influence of the emitted heat should be considered, and the applicable solution model for the compressible flow need to be determined. In this report, a brief overview of the current technology status will be presented and a program for further evaluation of this approach is going to be proposed.

Keywords: CO₂ sequestration, converging diverging nozzle, fossil fuel power plant emissions, inertial CO₂ extraction, supersonic post-combustion carbon dioxide capture

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Authors: Pramit Garg, Vikas Kumar

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In December 2015, all the members of the United Nations Framework Convention on Climate Change (UNFCCC) unanimously adopted the historic Paris Agreement. As per the convention, 197 countries have followed the guidelines of the agreement and have agreed to reduce the use of fossil fuels and also reduce the carbon emission to reach net carbon neutrality by 2050 and reduce the global temperature by 2°C by the year 2100. Globally, transport accounts for 23% of the energy-related CO2 that feeds global warming. Decarbonization of the transport sector is an essential step towards achieving India’s nationally determined contributions and net zero emissions by 2050. Metro rail systems are playing a vital role in the decarbonization of the transport sector as they create metro cities for the “21st-century world” that could ensure “mobility, connectivity, productivity, safety and sustainability” for the populace. Metro rail was introduced in Delhi in 2002 to decarbonize Delhi-National Capital Region and to provide a sustainable mode of public transportation. Metro Rail Projects significantly contribute to pollution reduction and are thus a prerequisite for sustainable development. The Delhi Metro is the 1ˢᵗ metro system in the world to earn carbon credits from Clean Development Mechanism (CDM) projects registered under United Nations Framework Convention on Climate Change. A good Metro Project with reasonable network coverage attracts a modal shift from various private modes and hence fewer vehicles on the road, thus restraining the pollution at the source. The absence of Greenhouse Gas emissions from the vehicle of modal shift passengers and lower emissions due to decongested roads contribute to the reduction in Green House Gas emissions and hence overall reduction in atmospheric pollution. The reduction in emission during the horizon year 2002 to 2019 has been estimated using emission standards and deterioration factor(s) for different categories of vehicles. Presently, our results indicate that the Delhi Metro system has reduced approximately 17.3% of motorized trips by road resulting in an emission reduction significantly. Overall, Delhi Metro, with an immediate catchment area of 17% of the National Capital Territory of Delhi (NCTD), is helping today to reduce 387 tonnes of emissions per day and 141.2 ktonnes of emissions yearly. The findings indicate that the Metro rail system is driving cities towards a more livable environment.

Keywords: Delhi metro, GHG emission, sustainable public transport, urban transport

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Authors: Gunjan Razdan, Priyanka Sreenath, Jagannath Behera, S. K. Mishra, Sunil Mehra

Abstract:

Uttar Pradesh is one of the poor performing states with high Malnutrition and Anaemia among adolescent girls resulting in high MMR, IMR and low birth weight rate. The rate of anaemia among adolescent girls has doubled in the past decade. Adolescents gain around 15-20% of their optimum height, 25-50% of the ideal adult weight and 45% of the skeletal mass by the age of 19. Poor intake of energy, protein and other nutrients is one of the factors for malnutrition and anaemia. METHODS: The cross-sectional survey using a mixed method (quantitative and qualitative) was adopted in this study. The respondents (adolescents, parents and frontline health workers) were selected randomly from 30 villages and surveyed through a semi-structured questionnaire for qualitative information and FGDs and IDIs for qualitative information. A 24 hours dietary recall method was adopted to estimate their dietary practices. A total of 1069 adolescent girls, 1067 boys, 1774 parents and 69 frontline functionaries were covered under the study. Percentages and mean were calculated for quantitative variable, and content analysis was carried out for qualitative data. RESULTS: Over 80 % of parents provided assertions that they understood the term balanced diet and strongly felt that their children were having balanced diet. However, only negligible 1.5 % of parents could correctly recount essential eight food groups and 22% could tell about four groups which was the minimum response expected to say respondents had fair knowledge on a balanced diet. Only 10 percent of parents could tell that balanced diet helps in physical and mental growth and only 2% said it has a protective role. Besides, qualitative data shows that the perception regarding balanced diet is having costly food items like nuts and fruits. The dietary intake of adolescents is very low despite the increased iron needs associated with physical growth and puberty.The consumption of green leafy vegetables (less than 35 %) and citrus fruits (less than 50%) was found to be low. CONCLUSIONS: The assertions on an understanding of term balanced diet are contradictory to the actual knowledge and practices. Knowledge on essential food groups and nutrients is crucial to inculcate healthy eating practices among adolescents. This calls for comprehensive communication efforts to improve the knowledge and dietary practices among adolescents.

Keywords: anemia, knowledge, malnutrition, perceptions

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Authors: Sasirin Srisomkiew, Sireewan Ratsadornasai, Tanomkwan Tipvong, Isariya Meesing

Abstract:

Cassava is an important food source in the tropics and has recently gained attention as a potential source of biofuel that can replace limited fossil fuel sources. As a result, the demand for cassava production to support industries both within the country and abroad has increased. In Thailand, most farmers prefer to grow cassava in sandy and sandy loam areas where the soil has low natural fertility. Cassava is a tuber plant that has large roots to store food, resulting in the absorption of large amounts of nutrients from the soil, such as nitrogen, phosphorus, and potassium. Therefore, planting cassava in the same area for a long period causes soil erosion and decreases soil fertility. The loss of soil fertility affects the economy, society, and food and energy security of the country. Therefore, it is necessary to know the level of soil fertility and the amount of nutrients in the soil. To address this problem, this study applies geo-informatics technology and mathematical equations to assess erosion and soil fertility and to analyze factors affecting the amount of cassava production in Maha Sarakham Province. The results show that the area for cassava cultivation has increased in every district of Maha Sarakham Province between 2015-2022, with the total area increasing to 180,922 rai or 5.47% of the province’s total area during this period. Furthermore, it was found that it is possible to assess areas with soil erosion problems that had a moderate level of erosion in areas with high erosion rates ranging from 5-15 T/rai/year. Soil fertility assessment and information obtained from the soil nutrient map for 2015–2023 reveal that farmers in the area have improved the soil by adding chemical fertilizers along with organic fertilizers, such as manure and green manure, to increase the amount of nutrients in the soil. This is because the soil resources of Maha Sarakham Province mostly have relatively low agricultural potential due to the soil texture being sand and sandy loam. In this scenario, the ability to absorb nutrients is low, and the soil holds little water, so it is naturally low in fertility. Moreover, agricultural soil problems were found, including the presence of saline soil, sandy soil, and acidic soil, which is a serious restriction on land use because it affects the release of nutrients into the soil. The results of this study may be used as a guideline for managing soil resources and improving soil quality to prevent soil degradation problems that may occur in the future.

Keywords: Cassava, geoinformatics, soil erosion, soil fertility, land use change

Procedia PDF Downloads 38