Search results for: high quality planting materials

Authors: Shehu Usman Hassan

Abstract:

Published accounting information in financial statements are required to provide various users - shareholders, employees, suppliers, creditors, financial analysts, stockbrokers and government agencies – with timely and reliable information useful for making prudent, effective and efficient decisions. The widespread failure in the financial information quality has created the need to improve the financial information quality and to strengthen the control of managers by setting up good firms structures. This paper investigates firm attributes from perspective of structure, monitoring, performance elements of listed deposit money banks in Nigeria. The study adopted correlational research design with balanced panel data of 14 banks as sample of the study using multiple regression as a tool of analysis. The result reveals that firms attributes (leverage, profitability, liquidity, bank size and bank growth) has as significant influence on earnings quality of listed deposit money banks in Nigeria after the adoption of IFRS, while the pre period shows that the selected firm attributes has no significant impact on earnings quality. It is therefore concluded that the adoption of IFRS is right and timely.

Keywords: earnings quality, firm attributes, listed deposit money bank, Nigeria

Procedia PDF Downloads 502

Authors: Syeda Fatima Manzelat

Abstract:

This chapter investigates the biodeterioration of parks in the UK caused by lichens, focusing on Campbell Park and Great Linford Manor Park in Milton Keynes. The study first isolates and identifies potent biodeteriogens responsible for potential biodeterioration in these parks, enumerating and recording different classes and genera of lichens known for their biodeteriorative properties. It then examines the implications of lichens on biodeterioration at historic sites within these parks, considering impacts on historic structures, the environment, and associated health risks. Conservation strategies and preventive measures are discussed before concluding.Lichens, characterized by their symbiotic association between a fungus and an alga, thrive on various surfaces including building materials, soil, rock, wood, and trees. The fungal component provides structure and protection, while the algal partner performs photosynthesis. Lichens collected from the park sites, such as Xanthoria, Cladonia, and Arthonia, were observed affecting the historic walls, objects, and trees. Their biodeteriorative impacts were visible to the naked eye, contributing to aesthetic and structural damage. The study highlights the role of lichens as bioindicators of pollution, sensitive to changes in air quality. The presence and diversity of lichens provide insights into the air quality and pollution levels in the parks. However, lichens also pose health risks, with certain species causing respiratory issues, allergies, skin irritation, and other toxic effects in humans and animals. Conservation strategies discussed include regular monitoring, biological and chemical control methods, physical removal, and preventive cleaning. The study emphasizes the importance of a multifaceted, multidisciplinary approach to managing lichen-induced biodeterioration. Future management practices could involve advanced techniques such as eco-friendly biocides and self-cleaning materials to effectively control lichen growth and preserve historic structures. In conclusion, this chapter underscores the dual role of lichens as agents of biodeterioration and indicators of environmental quality. Comprehensive conservation management approaches, encompassing monitoring, targeted interventions, and advanced conservation methods, are essential for preserving the historic and natural integrity of parks like Campbell Park and Great Linford Manor Park.

Keywords: biodeterioration, historic parks, algae, UK

Procedia PDF Downloads 20

Authors: Vijay Kumar, Mack Moyo, Johannes Van Staden

Abstract:

Lachenalia viridiflora is a critically endangered bulbous plant with high potential on the international floriculture market. In the present study, an efficient protocol for in vitro plantlet regeneration through somatic embryogenesis was developed. Embryogenic callus was established on Murashige and Skoog (MS) basal medium supplemented with various concentrations and combinations of picloram and thidiazuron (TDZ). A high number of SEs (28.5 ± 1.49) with at different developmental stages of somatic embryos (SEs: globular embryos, torpedo and cotyledon embryo with bipolar characteristics) was obtained on Murashige and Skoog (MS) (Murashige and Skoog 1962) medium with 2.5 μM picloram, and 1.0 μM TDZ. Histological and scanning electron microscopic (SEM) analysis confirmed the presence of somatic embryos. Mature somatic embryos germinated and developed into plantlets after 6 weeks on half/full strength MS medium. High plant regeneration frequency (91.11 %) was achieved on full-strength MS medium supplemented with 5 μM phloroglucinol (PG). Well-developed healthy plantlets were successfully acclimatized in the greenhouse with a survival rate of 80%. The result of this study is beneficial in the mass propagation of high-quality Lachenalia viridiflora clonal plants for the commercial horticultural market and also provides a platform for future genetic transformation studies on the plant.

Keywords: horticultural plant, Lachenalia viridiflora, phloroglucinol, somatic embryogenesis, thidiazuron

Procedia PDF Downloads 624

Authors: Clifford Kwakwa Amoah, De-Graft Owusu-Manu, Prince Antwi-Afari

Abstract:

Infrastructure is the lifeline for economic development of any country. Hence, obtaining infrastructure quality cannot be overemphasized. Nevertheless, challenges of infrastructure quality persist, and it is worse in developing countries despite the diverse study on the subject matter. Therefore, this study was formulated to identify the prevalent determinants of infrastructure quality using synthesis of extant literature (to identify key variables), and analysis of survey questionnaire of data collected by means of the inductive methodology approach, mean score ranking and descriptive statistics. The variables “partner with the private sector, growth stimulation and poverty reduction, and adherence to procurement core principles” were the most significant challenges that the government faces. Moreover, it would be of utmost concern to adopt some stringent measures to help improve and accelerate on the growth and development of the nation, thereby achieving the best quality required. This study is novel conducted to provide insight into some of the punitive measures, considered in ensuring that quality infrastructure is obtained in both developing (specifically) and developed economies. The research findings therefore provide some guidance for overcoming the accumulative challenges. Application of the stated findings will help bridge the gap of infrastructure challenges; this is because the study found strong empirical evidence that infrastructure plays a pivotal role in the productivity enhancement.

Keywords: challenges, development, economic growth, government, infrastructure quality

Procedia PDF Downloads 132

Authors: N. Tugrul, A. S. Kipcak, E. Moroydor Derun, S. Piskin

Abstract:

Zinc borate is an important boron compound that can be used as multi-functional flame retardant additive due to its high dehydration temperature property. In this study, the raw materials of ZnSO4.7H2O, NaOH and H3BO3 were characterized by X-Ray Diffraction (XRD) and Fourier Transform Infrared Spectroscopy (FT-IR) and used in the synthesis of zinc borates. The synthesis parameters were set to 100°C reaction temperature and 120 minutes of reaction time, with different molar ratio of starting materials (ZnSO4.7H2O:NaOH:H3BO3). After the zinc borate synthesis, the identifications of the products were conducted by XRD and FT-IR. As a result, Zinc Oxide Borate Hydrate [Zn3B6O12.3.5H2O], were synthesized at the molar ratios of 1:1:3, 1:1:4, 1:2:5 and 1:2:6. Among these ratios 1:2:6 had the best results.

Keywords: Zinc borate, ZnSO4.7H2O, NaOH, H3BO3, XRD, FT-IR

Procedia PDF Downloads 355

Authors: M. Kashfi, K. Jahani

Abstract:

Sound attenuation in absorptive silencers has been analyzed in this paper. The structure of such devices is as follows. When the rigid duct of an expansion chamber has been lined by a packed absorptive material under a perforated membrane, incident sound waves will be dissipated by the absorptive liners. This kind of silencer, usually are applicable for medium to high frequency ranges. Several conditions for different absorptive materials, variety in their thicknesses, and different shapes of the expansion chambers have been studied in this paper. Also, graphs of sound attenuation have been compared between empty expansion chamber and duct of silencer with applying liner. Plane waves have been assumed in inlet and outlet regions of the silencer. Presented results that have been achieved by applying finite element method (FEM), have shown the dependence of the sound attenuation spectrum to flow resistivity and the thicknesses of the absorptive materials, and geometries of the cross section (configuration of the silencer). As flow resistivity and thickness of absorptive materials increase, sound attenuation improves. In this paper, diagrams of the transmission loss (TL) for absorptive silencers in five different cross sections (rectangle, circle, ellipse, square, and rounded rectangle as the main geometry) have been presented. Also, TL graphs for silencers using different absorptive material (glass wool, wood fiber, and kind of spongy materials) as liner with three different thicknesses of 5 mm, 15 mm, and 30 mm for glass wool liner have been exhibited. At first, the effect of substances of the absorptive materials with the specific flow resistivity and densities on the TL spectrum, then the effect of the thicknesses of the glass wool, and at last the efficacy of the shape of the cross section of the silencer have been investigated.

Keywords: transmission loss, absorptive material, flow resistivity, thickness, frequency

Procedia PDF Downloads 244

Authors: Sanja O. Podunavac-Kuzmanović, Strahinja Z. Kovačević, Lidija R. Jevrić, Stela Jokić

Abstract:

The subject of this paper is to correlate antibacterial behavior of benzimidazole derivatives with their molecular characteristics using chemometric QSAR (Quantitative Structure–Activity Relationships) approach. QSAR analysis has been carried out on the inhibitory activity of benzimidazole derivatives against Staphylococcus aureus. The data were processed by linear least squares (LLS) and artificial neural network (ANN) procedures. The LLS mathematical models have been developed as a calibration models for prediction of the inhibitory activity. The quality of the models was validated by leave one out (LOO) technique and by using external data set. High agreement between experimental and predicted inhibitory acivities indicated the good quality of the derived models. These results are part of the CMST COST Action No. CM1306 "Understanding Movement and Mechanism in Molecular Machines".

Keywords: Antibacterial, benzimidazoles, chemometric, QSAR.

Procedia PDF Downloads 310

Authors: Anatoly D. Pluzhnikov, Elena N. Pribludova, Alexander G. Ryndyk

Abstract:

In conjunction with the problem of the target selection on a clutter background, the analysis of the scanning rate influence on the spatial-temporal signal structure, the generalized multivariate correlation function and the quality of the resolution with the increase pulse repetition frequency is made. The possibility of the object space-distance resolution, which is conditioned by the range-to-angle conversion with an increased scanning rate, is substantiated. The calculations for the real cylindrical array at high scanning rate are presented. The high scanning rate let to get the signal to noise improvement of the order of 10 dB for the space-time signal processing.

Keywords: antenna pattern, array, signal processing, spatial resolution

Procedia PDF Downloads 173

Authors: Vandita Mishra

Abstract:

From the management of patients, reception, record, and assistants in a clinical practice; to the management of ongoing research, clinical cases and department profile in an academic setup, the healthcare provider has to deal with all of it. The victory lies in smooth running of the show in both the above situations with an apt solution of problems encountered and smooth management of crisis faced. Thus this paper amalgamates dental science with health administration by means of introduction of a concept for practice management and problem-solving called 'Quality Circles'. This concept uses various tools for problem solving given by experts from different fields. QC tools can be applied in both clinical and academic settings in dentistry for better productivity and for scientifically approaching the process of continuous improvement in both the categories. When approached through QC, our organization showed better patient outcomes and more patient satisfaction. Introduced in 1962 by Kaoru Ishikawa, this tool has been extensively applied in certain fields outside dentistry and healthcare. By exemplification of some clinical cases and virtual scenarios, the tools of Quality circles will be elaborated and discussed upon.

Keywords: academics, dentistry, healthcare, quality

Procedia PDF Downloads 93

Authors: Martina Drdlová, Michal Frank, Radek Řídký, Jaroslav Buchar, Josef Krátký

Abstract:

The main aim of the presented experiments is to improve behaviour of sandwich structures under dynamic loading, such as crash or explosion. This paper describes experimental investigation on the response of new advanced materials to low and high velocity load. Blast wave energy absorbers were designed using two types of porous lightweight raw particle materials based on expanded glass and ceramics with dimensions of 0.5-1 mm, combined with polymeric binder. The effect of binder amount on the static and dynamic properties of designed materials was observed. Prism shaped specimens were prepared and loaded to obtain physico-mechanical parameters – bulk density, compressive and flexural strength under quasistatic load, the dynamic response was determined using Split Hopkinson Pressure bar apparatus. Numerical investigation of the material behaviour in sandwich structure was performed using implicit/explicit solver LS-Dyna. As the last step, the developed material was used as the interlayer of blast resistant litter bin, and it´s functionality was verified by real field blast tests.

Keywords: blast energy absorber, SHPB, expanded glass, expanded ceramics

Procedia PDF Downloads 454

Authors: Abubakar Dahiru Shuaibu, Atif Saeed Alzahrani, Md. Abdul Aziz

Abstract:

Construction of eco-benign, cost effective, and high-performance supercapacitors with improved electrolytes and hierarchical porous electrodes is necessary for effective energy storage. In this study, a gel type organic redox electrolyte made of polyvinyl alcohol (PVA)-H2SO4 and an organic redox molecule, anthraquinone (PVA-H2SO4-AQ), was prepared by simple solution casting method and was used to construct a symmetric supercapacitor (SSC) with a high BET surface area (1612 m²/g) using activated carbon made from date stones (DSAC). The DSAC was synthesized by simple carbonization method followed by activation with potassium hydroxide. The SSC exhibit a high specific capacitance of 126.5 F/g at 0.5 A/g, as well as a high energy density of 17.5 Wh/kg at a power density of 250 W/kg with high capacitance retention (87%) after 1000 GCD cycles. The present research suggests that adding anthraquinone to a PVA-H2SO4 gel electrolyte improves the performance of the fabricated device significantly as compared to using pristine PVA-H₂SO₄ or 1M H₂SO₄ electrolytes. The research also presents a promising approach for the development of sustainable and eco-benign materials for energy storage applications. The use of date stone waste as a precursor material for activated carbon electrodes presents an opportunity for cost-effective and sustainable energy storage. Overall, the findings of this research have important implications for the future design and fabrication of high-performance and cost-effective supercapacitors

Keywords: date stone, activated carbon, anthraquinone, redox gel-electrolyte, supercapacitor

Procedia PDF Downloads 73

Authors: Mohammed Alhadi Ebrahiem

Abstract:

This study was designed to investigate the effect of breed and feeding level before slaughter on the skin\leather quality of the three main breeds of Sudan goats. Thirty (30) pieces of fresh skins from the three goat breeds (an average age 1-1.5 years) were chosen for the study purpose. For whole variations between the three breeds in two levels of feeding (poor and rich pastures) Complete Randomized Design (CRD) was used for data analysis. The results revealed that, leather weight (kg), elongation%, tensile strength (kg/cm2), cracking load (kg), thickness (mm), tear load (kg/cm) and chrome% findings were significantly affected (P≥0.05) by breed variation. Flexibility, moisture%, Ash% and fat % were not significantly affected (P ≥ 0.05) by breed. On the other hand, skin weight (kg), Cracking load (kg), Tear load (kg/cm) and Ash% were significantly affected (P≥0.05) by pasture quality. While Leather Elongation%, Tensile strength (kg/cm2), Thickness (mm), Flexibility, Moisture%, Fat % and Chrome% were not statistically (P ≥ 0.05) affected by pastures quality.

Keywords: skin\leather quality, goats leather, natural pasture, Sudan

Procedia PDF Downloads 352

Authors: Matjaz Prek

Abstract:

Impact of three different combinations of cooling and ventilation systems on the indoor environmental quality (IEQ) has been studied. Comparison of chilled ceiling cooling in combination with displacement ventilation, cooling with fan coil unit and cooling with flat wall displacement outlets was performed. All three combinations were evaluated from the standpoint of whole-body and local thermal comfort criteria as well as from the standpoint of ventilation effectiveness. The comparison was made on the basis of numerical simulation with DesignBuilder and Fluent. Numerical simulations were carried out in two steps. Firstly the DesignBuilder software environment was used to model the buildings thermal performance and evaluation of the interaction between the environment and the building. Heat gains of the building and of the individual space, as well as the heat loss on the boundary surfaces in the room, were calculated. In the second step Fluent software environment was used to simulate the response of the indoor environment, evaluating the interaction between building and human, using the simulation results obtained in the first step. Among the systems presented, the ceiling cooling system in combination with displacement ventilation was found to be the most suitable as it offers a high level of thermal comfort with adequate ventilation efficiency. Fan coil cooling has proved inadequate from the standpoint of thermal comfort whereas flat wall displacement outlets were inadequate from the standpoint of ventilation effectiveness. The study showed the need in evaluating indoor environment not solely from the energy use point of view, but from the point of view of indoor environmental quality as well.

Keywords: cooling, ventilation, thermal comfort, ventilation effectiveness, indoor environmental quality, IEQ, computational fluid dynamics

Procedia PDF Downloads 181

Authors: Angel Fabian Mijangos, Jaime Alvarez Quintana

Abstract:

Waste heat occurs in many areas of daily life because world’s energy consumption is inefficient. In general, generating 1 watt of power requires about 3 watt of energy input and involves dumping into the environment the equivalent of about 2 watts of power in the form of heat. Therefore, an attractive and sustainable solution to the energy problem would be the development of highly efficient thermoelectric devices which could help to recover this waste heat. This work presents the influence on the thermoelectric properties of metallic, semiconducting, and dielectric nanoparticles added into the grain boundaries of polycrystalline antimony (Sb) and bismuth (Bi) matrixes in order to obtain p- and n-type thermoelectric materials, respectively, by hot pressing methods. Results show that thermoelectric properties are significantly affected by the electrical and thermal nature as well as concentration of nanoparticles. Nevertheless, by optimizing the amount of the nanoparticles on the grain boundaries, an oscillatory behavior in ZT as function of the concentration of the nanoscale constituents is present. This effect is due to energy filtering mechanism which module the quantity of charge transport in the system and affects thermoelectric properties. Accordingly, a ZTmax can be accomplished through the addition of the appropriate amount of nanoparticles into the grain boundaries region. In this case, till three orders of amelioration on ZT is reached in both systems compared with the reference sample of each one. This approach paves the way to pursuit high performance thermoelectric materials in a simple way and opens a new route towards the enhancement of the thermoelectric figure of merit.

Keywords: energy filtering, grain boundaries, thermoelectric, nanostructured materials

Procedia PDF Downloads 250

Authors: Collins Molua

Abstract:

This paper investigated the effect of Teaching Strategies on Academic Achievement in Secondary Physics Education as a quality assurance process for the teaching and learning of the subject. Teaching strategies investigated were the interactive, independent and dependent strategies. Three null hypotheses were tested at p< 0.05 using one instrument, physics achievement test(PAT).The data were analyzed using analysis of covariance (ANCOVA).Results showed that teaching strategies have significant effect on students achievement; the joint effect of the teaching strategies was also significant on students achievement in Physics. The interactive teaching strategies was recommended for teaching the subject and the students should be exposed to practical, computer literacy to stimulate interest and curiosity to enhance quality.

Keywords: quality, assurance, secondary education, strategies, physics

Procedia PDF Downloads 316

Authors: Daryl Clement Knutt, Neela Badrie, Marsha Singh

Abstract:

Quality assurance and product labelling are vital in the food and drink industry, as a tactical tool in a competitive environment. The food label is a principal marketing tool which also serves as a regulatory mechanism in the safeguarding of consumer well –being. The objective of this study was to evaluate the level of consumers’ use and understanding of food labeling information and knowledge pertaining to food quality assurance systems. The study population consisted of Trinidadian adults, who were over the age of 18 (n=384). Data collection was conducted via a self-administered questionnaire, which contained 31 questions, comprising of four sections: I. socio demographic information; II. food quality and quality assurance; III. use of Labeling information; and IV. laws and regulations. Sampling was conducted at six supermarkets, in five major regions of the country over a period of three weeks in 2014. The demographic profile of the shoppers revealed that majority was female (63.6%). The gender factor and those who were concerned about the nutrient content of their food, were predictive indicators of those who read food labels. Most (93.1%) read food labels before purchase, 15.4% ‘always’; 32.5% ‘most times’ and 45.2% ‘sometimes’. Some (42%) were often satisfied with the information presented on food labels, whilst 35.7% of consumers were unsatisfied. When the respondents were questioned on their familiarity with terms ‘food quality’ and ‘food quality assurance’, 21.3% of consumers replied positively - ‘I have heard the terms and know a lot’ whilst 37% were only ‘somewhat familiar’. Consumers were mainly knowledgeable of the International Standard of Organization (ISO) (51.5%) and Good Agricultural Practices GAP (38%) as quality tools. Participants ranked ‘nutritional information’ as the number one labeling element that should be better presented, followed by ‘allergy notes’ and ‘best before date’. Females were more inclined to read labels being the household shoppers. The shoppers would like better presentation of the food labelling information so as to guide their decision to purchase a product.

Keywords: food labels, food quality, nutrition, marketing, Trinidad, Tobago

Procedia PDF Downloads 480

Authors: Natalia C. E. S. Nascimento, Mercia L. Oliveira, Fernando R. A. Lima, Leonardo T. C. do Nascimento, Marina B. Silveira, Brigida G. A. Schirmer, Andrea V. Ferreira, Carlos Malamut, Juliana B. da Silva

Abstract:

Tissue hypoxia is a common characteristic of solid tumors leading to decreased sensitivity to radiotherapy and chemotherapy. In the clinical context, tumor hypoxia assessment employing the positron emission tomography (PET) tracer ¹⁸F-fluoromisonidazole ([¹⁸F]FMISO) is helpful for physicians for planning and therapy adjusting. The aim of this work was to implement the synthesis of 18F-FMISO in a TRACERlab® MXFDG module and also to establish the quality control procedure. [¹⁸F]FMISO was synthesized at Centro de Desenvolvimento da Tecnologia Nuclear (CDTN/CNEN/Brazil) using an automated synthesizer (TRACERlab® MXFDG, GE) adapted for the production of [¹⁸F]FMISO. The FMISO chemical standard was purchased from ABX. 18O- enriched water was acquired from Center of Molecular Research. Reagent kits containing eluent solution, acetonitrile, ethanol, 2.0 M HCl solution, buffer solution, water for injections and [¹⁸F]FMISO precursor (dissolved in 2 ml acetonitrile) were purchased from ABX. The [¹⁸F]FMISO samples were purified by Solid Phase Extraction method. The quality requirements of [¹⁸F]FMISO are established in the European Pharmacopeia. According to that reference, quality control of [¹⁸F]FMISO should include appearance, pH, radionuclidic identity and purity, radiochemical identity and purity, chemical purity, residual solvents, bacterial endotoxins, and sterility. The duration of the synthesis process was 53 min, with radiochemical yield of (37.00 ± 0.01) % and the specific activity was more than 70 GBq/µmol. The syntheses were reproducible and showed satisfactory results. In relation to the quality control analysis, the samples were clear and colorless at pH 6.0. The spectrum emission, measured by using a High-Purity Germanium Detector (HPGe), presented a single peak at 511 keV and the half-life, determined by the decay method in an activimeter, was (111.0 ± 0.5) min, indicating no presence of radioactive contaminants, besides the desirable radionuclide (¹⁸F). The samples showed concentration of tetrabutylammonium (TBA) < 50μg/mL, assessed by visual comparison to TBA standard applied in the same thin layer chromatographic plate. Radiochemical purity was determined by high performance liquid chromatography (HPLC) and the results were 100%. Regarding the residual solvents tested, ethanol and acetonitrile presented concentration lower than 10% and 0.04%, respectively. Healthy female mice were injected via lateral tail vein with [¹⁸F]FMISO, microPET imaging studies (15 min) were performed after 2 h post injection (p.i), and the biodistribution was analyzed in five-time points (30, 60, 90, 120 and 180 min) after injection. Subsequently, organs/tissues were assayed for radioactivity with a gamma counter. All parameters of quality control test were in agreement to quality criteria confirming that [¹⁸F]FMISO was suitable for use in non-clinical and clinical trials, following the legal requirements for the production of new radiopharmaceuticals in Brazil.

Keywords: automatic radiosynthesis, hypoxic tumors, pharmacopeia, positron emitters, quality requirements

Procedia PDF Downloads 185

Authors: S. Akinde, Jubril Olatunbosun

Abstract:

In recent years, most of the urban centers in Nigeria are fast experiencing housing problems such as unaffordable housing and environmental challenges, all of which determine the nature of housing quality. The population continues to increase and the demand for quality housing increases probably at the same rate. Several kinds of houses serve various purposes; the objectives of the low cost housing schemes as the name suggests is to make houses quality to both the middle and lower classes of people in Lagos. A casual look into the study area of Iba Low Cost Housing Estate and the Unity Low Cost Housing Estate, Ojo and Alimosho respectively in Lagos State have shown a huge demands for houses. The study area boasts of a large population all engaged in various commercial activities with income at various levels. It would be fair to say that these people are mainly of the middle class and lower class. This means the low cost housing scheme truly serves these purposes. A Low Cost Housing Scheme of Iba which is publicly owned and Low Cost Housing Scheme of Unity Estate (UE) is privately owned.  

Keywords: housing, residential quality, low cost housing scheme, public, private estates

Procedia PDF Downloads 549

Authors: S. Iffat, B. Bose

Abstract:

Concrete as a construction material is versatile because it displays high degree of fire-resistance. Concrete’s inherent ability to combat one of the most devastating disaster that a structure can endure in its lifetime, can be attributed to its constituent materials which make it inert and have relatively poor thermal conductivity. However, concrete structures must be designed for fire effects. Structural components should be able to withstand dead and live loads without undergoing collapse. The properties of high-strength concrete must be weighed against concerns about its fire resistance and susceptibility to spalling at elevated temperatures. In this paper, the causes, effects and some remedy of deterioration in concrete due to fire hazard will be discussed. Some cost effective solutions to produce a fire resistant concrete will be conversed through this paper.

Keywords: concrete, fire, spalling, temperature, compressive strength, density

Procedia PDF Downloads 437

Authors: Tuba Sari

Abstract:

One of the major transformations caused by the industrial revolution, technological developments and globalization is undoubtedly acceleration of urbanization process. Globalization, in particular, is one of the major factors that trigger this transformation. In this context, as a result of the global metropolitan city system, multifunctional rising structure forms are becoming undeniable fact of the world’s leading metropolises as the manifestation of prestige and power with different life choices, easy accessibility to services related to the era of technology. The scope of research deals with five different urban centers in İstanbul where high-rise housing is increasing dramatically after 2000’s. Therefore, the research regards multi-centered urban residential pattern being created by high-rise housing structures in the city. The methodology of the research is based on two main issue, one of them is related to sampling method of high-rise housing projects in İstanbul, while the other method of the research is based on the model of Semantics. In the framework of research hypothesis, it is aimed to prove that the character of vertical intensive structuring in Istanbul is based on seeking of different forms and images in the expressive quality, considering the production of existing high-rise buildings in residential areas in recent years. In respect to rising discourse of 'World City' in the globalizing world, it is very important to state the place of Istanbul in other developing world metropolises. In the perspective of 'World City' discourse, Istanbul has different projects concerning with globalization, international finance companies, cultural activities, mega projects, etc. In brief, the aim of this research is examining transformation forms of high-rise housing development in Istanbul within the frame of developing world cities, searching and analyzing discourse and image related to these projects.

Keywords: globalization, high-rise, housing, image

Procedia PDF Downloads 275

Authors: Pedro A. V. Ramos, Duarte M. S. Albuquerque, José C. F. Pereira

Abstract:

Global warming mitigation is one of the main challenges of this century, having the net balance of greenhouse gas (GHG) emissions to be null or negative in 2050. Industry electrification is one of the main paths to achieving carbon neutrality within the goals of the Paris Agreement. Microwave heating is becoming a popular industrial heating mechanism due to the absence of direct GHG emissions, but also the rapid, volumetric, and efficient heating. In the present study, a mathematical model is used to simulate the production using microwave heating of two ceramic pigments, at high temperatures (above 1200 Celsius degrees). The two pigments studied were the yellow (Pr, Zr)SiO₂ and the brown (Ti, Sb, Cr)O₂. The chemical conversion of reactants into products was included in the model by using the kinetic triplet obtained with the model-fitting method and experimental data present in the Literature. The coupling between the electromagnetic, thermal, and chemical interfaces was also included. The simulations were computed in COMSOL Multiphysics. The geometry includes a moving plunger to allow for the cavity impedance matching and thus maximize the electromagnetic efficiency. To accomplish this goal, a MATLAB controller was developed to automatically search the position of the moving plunger that guarantees the maximum efficiency. The power is automatically and permanently adjusted during the transient simulation to impose stationary regime and total conversion, the two requisites of every converged solution. Both 2D and 3D geometries were used and a parametric study regarding the axial bed velocity and the heat transfer coefficient at the boundaries was performed. Moreover, a Verification and Validation study was carried out by comparing the conversion profiles obtained numerically with the experimental data available in the Literature; the numerical uncertainty was also estimated to attest to the result's reliability. The results show that the model-fitting method employed in this work is a suitable tool to predict the chemical conversion of reactants into the pigment, showing excellent agreement between the numerical results and the experimental data. Moreover, it was demonstrated that higher velocities lead to higher thermal efficiencies and thus lower energy consumption during the process. This work concludes that the electromagnetic heating of materials having high loss tangent and low thermal conductivity, like ceramic materials, maybe a challenge due to the presence of hot spots, which may jeopardize the product quality or even the experimental apparatus. The MATLAB controller increased the electromagnetic efficiency by 25% and global efficiency of 54% was obtained for the titanate brown pigment. This work shows that electromagnetic heating will be a key technology in the decarbonization of the ceramic sector as reductions up to 98% in the specific GHG emissions were obtained when compared to the conventional process. Furthermore, numerical simulations appear as a suitable technique to be used in the design and optimization of microwave applicators, showing high agreement with experimental data.

Keywords: automatic impedance matching, ceramic pigments, efficiency maximization, high-temperature microwave heating, input power control, numerical simulation

Procedia PDF Downloads 132

Authors: Elhussein Ahmed Elsayed

Abstract:

An ancient limestone stela dating back to the epoch of the middle kingdom and displayed in the exhibition hall of the middle kingdom, it was discovered in Lisht in Giza, registered with No. 3045 and as a result of its display in an inappropriate display as a result of the use of natural lighting in the display, Represented in sunlight through windows opened day and night. The alternation of these daily changes between the temperature degrees of night and day, both daily and seasonally, causes the expansion and contraction of the rocks and then weakens their cohesion, causing fragmentation. This is indeed the current situation of this stela displayed in the hall, in addition to the damage and fading of colors, as well as the use of a high-viscosity restoration material in the consolidation that led to the attraction of dust and dirt and its adhesion to the surface. The color faded as a result of the lack of lighting control inside the exhibition hall, the remnants of the existing colors were blurred as a result of applying a consolidation material with a high viscosity, which led to the attraction of dust and dirt, and then blurring the colors on the inscription. Examinations and analyzes were carried out on the block, and the results of the examination with a polarized microscope showed that it is of primitive limestone, which contains fossils and microorganisms, which helps to damage. The analysis using the Raman device also showed that the high-viscosity material used in restoration in the past is Paralloid B72. The stone stela was consolidated by using two materials; Nano calcium hydroxide with Nano silica in the form of (Core-shell) at a concentration of 10% and it was applied using the brush.

Keywords: Egyptian museum, stone stela, treatment, nano materials, nano silica

Procedia PDF Downloads 71

Authors: Ubaka Chukwuemeka Michael, Ukwe Chinwe Victoria

Abstract:

Background: The use of antipsychotic monotherapy remains the standard for schizophrenic disorders so also a prescription switch from older typical to newer atypical classes of antipsychotics on the basis of better efficacy and tolerability. However, surveys on the quality of antipsychotic drug use and substitution in developing countries are very scarce. This study was intended to evaluate quality and factors that drive the prescription and substitution of antipsychotic drugs among schizophrenic patients visiting a regional psychiatric hospital. Methods: Case files of patients visiting a federal government funded Neuropsychiatric Hospital between July 2012 and July 2014 were systematically retrieved. Patient demographic characteristics, clinical details and drug management data were collected and subjected to descriptive and inferential data analysis to determine quality and predictors of utilization. Results: Of the 600 case files used, there were more male patients (55.3%) with an overall mean age of 33.7±14.4 years. Typical antipsychotic agents accounted for over 85% of prescriptions, with majority of the patients receiving more than 2 drugs in at least a visit (80.9%). Fluphenazine (25.2%) and Haloperidol (18.8%) were mostly given as antipsychotics for treatment initiation while Olazenpine (23.0%) and Benzhexol (18.3%) were the most currently prescribed antipsychotics. Nearly half (42%, 252/600) of these patients were switched from one class to another, with 34.5% (207/600) of them switched from typical to atypical drug classes. No demographic or clinical factors influenced drug substitutions but a younger age and being married influenced being prescribed a polypharmacy regimen (more than 2 drugs) and an injectable antipsychotic agent. Conclusion: The prevalence of antipsychotic polypharmacy and use of typical agents among these patients was high. However, only age and marital status affected the quality of antipsychotic prescriptions among these patients.

Keywords: antipsychotics, drug substitution, pharmacoepidemiology, polypharmacy

Procedia PDF Downloads 466

Authors: Amir Nourbakhsh Habibabadi, Alireza Ashori

Abstract:

Context: The growing concern over the management of plastic waste and the high demand for wood-based products have led to the development of wood-plastic composites. Agricultural residues, which are abundantly available, can be used as a source of lignocellulosic fibers in the production of these composites. The use of recycled polymers and nanomaterials is also a promising approach to enhance the mechanical and physical properties of the composites. Research Aim: The aim of this study was to investigate the feasibility of using recycled high-density polyethylene (rHDPE), polypropylene (rPP), and agricultural residues fibers for manufacturing wood-plastic nano-composites. The effects of these materials on the mechanical properties of the composites, specifically tensile and flexural strength, were studied. Methodology: The study utilized an experimental approach where extruders and hot presses were used to fabricate the composites. Five types of cellulosic residues fibers (bagasse, corn stalk, rice straw, sunflower, and canola stem), three levels of nanomaterials (carbon nanotubes, nano silica, and nanoclay), and coupling agent were used to chemically bind the wood/polymer fibers, chemicals, and reinforcement. The mechanical properties of the composites were then analyzed. Findings: The study found that composites made with rHDPE provided moderately superior tensile and flexural properties compared to rPP samples. The addition of agricultural residues in several types of wood-plastic nano-composites significantly improved their bending and tensile properties, with bagasse having the most significant advantage over other lignocellulosic materials. The use of recycled polymers, agricultural residues, and nano-silica resulted in composites with the best strength properties. Theoretical Importance: The study's findings suggest that using agricultural fiber residues as reinforcement in wood/plastic nanocomposites is a viable approach to improve the mechanical properties of the composites. Additionally, the study highlights the potential of using recycled polymers in the development of value-added products without compromising the product's properties. Data Collection and Analysis Procedures: The study collected data on the mechanical properties of the composites using tensile and flexural tests. Statistical analyses were performed to determine the significant effects of the various materials used. Question addressed: Can agricultural residues and recycled polymers be used to manufacture wood-plastic nano-composites with enhanced mechanical properties? Conclusion: The study demonstrates the feasibility of using agricultural residues and recycled polymers in the production of wood-plastic nano-composites. The addition of these materials significantly improved the mechanical properties of the composites, with bagasse being the most effective agricultural residue. The study's findings suggest that composites made from recycled materials can offer value-added products without sacrificing performance.

Keywords: polymer, composites, wood, nano

Procedia PDF Downloads 64

Authors: J. Skibinski, P. Caban, T. Wejrzanowski, K. J. Kurzydlowski

Abstract:

In the present study, numerical simulations of heat and mass transfer during gallium nitride growth process in Metal Organic Vapor Phase Epitaxy reactor AIX-200/4RF-S is addressed. Existing knowledge about phenomena occurring in the MOVPE process allows to produce high quality nitride based semiconductors. However, process parameters of MOVPE reactors can vary in certain ranges. Main goal of this study is optimization of the process and improvement of the quality of obtained crystal. In order to investigate this subject a series of computer simulations have been performed. Numerical simulations of heat and mass transfer in GaN epitaxial growth process have been performed to determine growth rate for various mass flow rates and pressures of reagents. According to the fact that it’s impossible to determine experimentally the exact distribution of heat and mass transfer inside the reactor during the process, modeling is the only solution to understand the process precisely. Main heat transfer mechanisms during MOVPE process are convection and radiation. Correlation of modeling results with the experiment allows to determine optimal process parameters for obtaining crystals of highest quality.

Keywords: Finite Volume Method, semiconductors, epitaxial growth, metalorganic vapor phase epitaxy, gallium nitride

Procedia PDF Downloads 391

Authors: G. Suja, J. Sreekumar, A. N. Jyothi, V. S. Santhosh Mithra

Abstract:

Worldwide concerns regarding food safety, environmental degradation and threats to human health have generated interest in alternative systems like organic farming. Tropical tuber crops, cassava, sweet potato, yams, and aroids are food-cum-nutritional security-cum climate resilient crops. These form stable or subsidiary food for about 500 million global population. Cassava, yams (white yam, greater yam, and lesser yam) and edible aroids (elephant foot yam, taro, and tannia) are high energy tuberous vegetables with good taste and nutritive value. Seven on-station field experiments at ICAR-Central Tuber Crops Research Institute, Thiruvananthapuram, India and seventeen on-farm trials in three districts of Kerala, were conducted over a decade (2004-2015) to compare the varietal response, yield, quality and soil properties under organic vs conventional system in these crops and to develop a learning system based on the data generated. The industrial, as well as domestic varieties of cassava, the elite and local varieties of elephant foot yam and taro and the three species of Dioscorea (yams), were on a par under both systems. Organic management promoted yield by 8%, 20%, 9%, 11% and 7% over conventional practice in cassava, elephant foot yam, white yam, greater yam and lesser yam respectively. Elephant foot yam was the most responsive to organic management followed by yams and cassava. In taro, slight yield reduction (5%) was noticed under organic farming with almost similar tuber quality. The tuber quality was improved with higher dry matter, starch, crude protein, K, Ca and Mg contents. The anti-nutritional factors, oxalate content in elephant foot yam and cyanogenic glucoside content in cassava were lowered by 21 and 12.4% respectively. Organic plots had significantly higher water holding capacity, pH, available K, Fe, Mn and Cu, higher soil organic matter, available N, P, exchangeable Ca and Mg, dehydrogenase enzyme activity and microbial count. Organic farming scored significantly higher soil quality index (1.93) than conventional practice (1.46). The soil quality index was driven by water holding capacity, pH and available Zn followed by soil organic matter. Organic management enhanced net profit by 20-40% over chemical farming. A case in point is the cost-benefit analysis in elephant foot yam which indicated that the net profit was 28% higher and additional income of Rs. 47,716 ha-1 was obtained due to organic farming. Cost-effective technologies were field validated. The on-station technologies developed were validated and popularized through on-farm trials in 10 sites (5 ha) under National Horticulture Mission funded programme in elephant foot yam and seven sites in yams and taro. The technologies are included in the Package of Practices Recommendations for crops of Kerala Agricultural University. A learning system developed using artificial neural networks (ANN) predicted the performance of elephant foot yam organic system. Use of organically produced seed materials, seed treatment in cow-dung, neem cake, bio-inoculant slurry, farmyard manure incubated with bio-inoculants, green manuring, use of neem cake, bio-fertilizers and ash formed the strategies for organic production. Organic farming is an eco-friendly management strategy that enables 10-20% higher yield, quality tubers and maintenance of soil health in tuber crops.

Keywords: eco-agriculture, quality, root crops, healthy soil, yield

Procedia PDF Downloads 328

Authors: Jose Daniel Giraldo Arias, Camilo Rojas Gomez, David Villegas Delgado, Gullermo Idarraga Alarcon, Juan Meza Meza

Abstract:

The reverse engineering processes are widely used in the industry with the main goal to determine the materials and the manufacture used to produce a component. There are a lot of characterization techniques and computational tools that are used in order to get this information. A study case of a reverse engineering applied to a secondary sandwich- hybrid type structure used in a helicopter is presented. The methodology used consists of five main steps, which can be applied to any other similar component: Collect information about the service conditions of the part, disassembly and dimensional characterization, functional characterization, material properties characterization and manufacturing processes characterization, allowing to obtain all the supports of the traceability of the materials and processes of the aeronautical products that ensure their airworthiness. A detailed explanation of each step is covered. Criticality and comprehend the functionalities of each part, information of the state of the art and information obtained from interviews with the technical groups of the helicopter’s operators were analyzed,3D optical scanning technique, standard and advanced materials characterization techniques and finite element simulation allow to obtain all the characteristics of the materials used in the manufacture of the component. It was found that most of the materials are quite common in the aeronautical industry, including Kevlar, carbon, and glass fibers, aluminum honeycomb core, epoxy resin and epoxy adhesive. The stacking sequence and volumetric fiber fraction are a critical issue for the mechanical behavior; a digestion acid method was used for this purpose. This also helps in the determination of the manufacture technique which for this case was Vacuum Bagging. Samples of the material were manufactured and submitted to mechanical and environmental tests. These results were compared with those obtained during reverse engineering, which allows concluding that the materials and manufacture were correctly determined. Tooling for the manufacture was designed and manufactured according to the geometry and manufacture process requisites. The part was manufactured and the mechanical, and environmental tests required were also performed. Finally, a geometric characterization and non-destructive techniques allow verifying the quality of the part.

Keywords: reverse engineering, sandwich-structured composite parts, helicopter, mechanical properties, prototype

Procedia PDF Downloads 405

Authors: Bhanu Pant, Sanjay H. Upadhyay

Abstract:

Frequently, the upper stage of high-performance launch vehicles utilizes cryogenic tank-submerged pressurization gas bottles with high volume-to-weight efficiency to achieve a direct gain in the satellite payload. Titanium alloys, owing to their high specific strength coupled with excellent compatibility with various fluids, are the materials of choice for these applications. Amongst the Titanium alloys, there are two alloys suitable for cryogenic applications, namely Ti6Al4V-ELI and Ti5Al2.5Sn-ELI. The two-phase alpha-beta alloy Ti6Al4V-ELI is usable up to LOX temperature of 90K, while the single-phase alpha alloy Ti5Al2.5Sn-ELI can be used down to LHe temperature of 4 K. The high-pressure gas bottles submerged in the LH2 (20K) can store more amount of gas in as compared to those submerged in LOX (90K) bottles the same volume. Thus, the use of these alpha alloy gas bottles stored at 20K gives a distinct advantage with respect to the need for a lesser number of gas bottles to store the same amount of high-pressure gas, which in turn leads to a one-to-one advantage in the payload in the satellite. The cost advantage to the tune of 15000$/ kg of weight is saved in the upper stages, and, thereby, the satellite payload gain is expected by this change. However, the processing of alpha Ti5Al2.5Sn-ELI alloy gas bottles poses challenges due to the lower forgeability of the alloy and mode of qualification for the critical severe application environment. The present paper describes the processing and challenges/ solutions during the development of these advanced gas bottles for LH2 (20K) applications.

Keywords: titanium alloys, cryogenic gas bottles, alpha titanium alloy, alpha-beta titanium alloy

Procedia PDF Downloads 48

Authors: Carrie Ho, Tan Yee Yong

Abstract:

Urban runoff quality for a mixed residential-commercial land use catchment in Miri, Sarawak was investigated for three storm events in 2011. Samples from the three storm events were tested for five water quality parameters, Namely, TSS, COD, BOD5, TP, and Pb. Concentration of the pollutants were found to vary significantly between storms, but were generally influenced by the length of antecedent dry period and the strength of rainfall intensities. Runoff from the study site showed a significant level of pollution for all the parameters investigated. Based on the National Water Quality Standards for Malaysia (NWQS), stormwater quality from the study site was polluted and exceeded class III water for TSS and BOD5 with maximum EMCs of 177 and 24 mg/L, respectively. Design pollutant load based on a design storm of 3-month average recurrence interval (ARI) for TSS, COD, BOD5, TP, and Pb were estimated to be 40, 9.4, 5.4, 1.7, and 0.06 kg/ha, respectively. The design pollutant load for the pollutants can be used to estimate loadings from similar catchments within Miri City.

Keywords: mixed land-use, urban runoff, pollutant load, national water quality

Procedia PDF Downloads 324

Authors: Aurelia Samuel

Abstract:

Socio-economic modelling approaches linked to water management have contributed to impact assessments of agricultural policies and management practices on water quality at catchment level. With an increasing interest in informing water management policy that considers complex links between socioeconomic factors, climate change, agricultural production, and water quality, several models have been developed and applied in the literature to capture these relationships. This paper offers an overview of socio-economic approaches that have been incorporated within an integrated framework. It also highlights how data gaps on socio-economic factors have been addressed using forecasting techniques. Findings of the review show that while integrated frameworks have the potential to account for complexities within dynamic systems, they generally do not provide direct, measurable financial impact of socio-economic factors on biophysical water parameters that affect water quality. The paper concludes with a recommendation that modelling framework is kept simple to make it more transparent and easier to capture the most important relationship.

Keywords: financial impact, integrated framework, socio-economic modelling, water quality

Procedia PDF Downloads 147