Search results for: double curved surface

Authors: Wenjuan Du, Jingtian Bi, Tong Wang, Haifeng Wang

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Grid connection of a large-scale wind farm affects power system small-signal angular stability in two aspects. Firstly, connection of the wind farm brings about the change of load flow and configuration of a power system. Secondly, the dynamic interaction is introduced by the wind farm with the synchronous generators (SGs) in the power system. This paper proposes a method to assess the two aspects of the effect of the wind farm on power system small-signal angular stability. The effect of the change of load flow/system configuration brought about by the wind farm can be examined separately by displacing wind farms with constant power sources, then the effect of the dynamic interaction of the wind farm with the SGs can be also computed individually. Thus, a clearer picture and better understanding on the power system small-signal angular stability as affected by grid connection of the large-scale wind farm are provided. In the paper, an example power system with grid connection of a wind farm is presented to demonstrate the proposed approach.

Keywords: power system small-signal angular stability, power system low-frequency oscillations, electromechanical oscillation modes, wind farms, double fed induction generator (DFIG)

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Authors: Abhishek Sharma, Arnab Banerjee

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The research is intended to study the solar electric propulsion (SEP) technology for planetary missions. The main benefits of using solar electric propulsion for such missions are shorter flight times, more frequent target accessibility and the use of a smaller launch vehicle than that required by a comparable chemical propulsion mission. Energized by electric power from on-board solar arrays, the electrically propelled system uses 10 times less propellant than conventional chemical propulsion system, yet the reduced fuel mass can provide vigorous power which is capable of propelling robotic and crewed missions beyond the Lower Earth Orbit (LEO). The various thrusters used in the SEP are gridded ion thrusters and the Hall Effect thrusters. The research is solely aimed to study the ion thrusters and investigate the complications related to it and what can be done to overcome the glitches. The ion thrusters are used because they are found to have a total lower propellant requirement and have substantially longer time. In the ion thrusters, the anode pushes or directs the incoming electrons from the cathode. But the anode is not maintained at a very high potential which leads to divergence. Divergence leads to the charges interacting against the surface of the thruster. Just as the charges ionize the xenon gases, they are capable of ionizing the surfaces and over time destroy the surface and hence contaminate it. Hence the lifetime of thruster gets limited. So a solution to this problem is using substances which are not easy to ionize as the surface material. Another approach can be to increase the potential of anode so that the electrons don’t deviate much or reduce the length of thruster such that the positive anode is more effective. The aim is to work on these aspects as to how constriction of the deviation of charges can be done by keeping the input power constant and hence increase the lifetime of the thruster. Predominantly ring cusp magnets are used in the ion thrusters. However, the study is also intended to observe the effect of using solenoid for producing micro-solenoidal magnetic field apart from using the ring cusp magnetic field which are used in the discharge chamber for prevention of interaction of electrons with the ionization walls. Another foremost area of interest is what are the ways by which power can be provided to the Solar Electric Propulsion Vehicle for lowering and boosting the orbit of the spacecraft and also provide substantial amount of power to the solenoid for producing stronger magnetic fields. This can be successfully achieved by using the concept of Electro-dynamic tether which will serve as a power source for powering both the vehicle and the solenoids in the ion thruster and hence eliminating the need for carrying extra propellant on the spacecraft which will reduce the weight and hence reduce the cost of space propulsion.

Keywords: electro-dynamic tether, ion thruster, lifetime of thruster, solar electric propulsion vehicle

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Authors: Khalid Iqbal

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This work presents a comparison of an anthropomorphic PRESAGE® dosimeter and radiochromic film measurements with a commercial treatment planning system to determine the feasibility of PRESAGE® for 3D dosimetry in breast IMRT. An anthropomorphic PRESAGE® phantom was created in the shape of a breast phantom. A five-field IMRT plan was generated with a commercially available treatment planning system and delivered to the PRESAGE® phantom. The anthropomorphic PRESAGE® was scanned with the Duke midsized optical CT scanner (DMOS-RPC) and the OD distribution was converted to dose. Comparisons were performed between the dose distribution calculated with the Pinnacle3 treatment planning system, PRESAGE®, and EBT2 film measurements. DVHs, gamma maps, and line profiles were used to evaluate the agreement. Gamma map comparisons showed that Pinnacle3 agreed with PRESAGE® as greater than 95% of comparison points for the PTV passed a ± 3%/± 3 mm criterion when the outer 8 mm of phantom data were discluded. Edge artifacts were observed in the optical CT reconstruction, from the surface to approximately 8 mm depth. These artifacts resulted in dose differences between Pinnacle3 and PRESAGE® of up to 5% between the surface and a depth of 8 mm and decreased with increasing depth in the phantom. Line profile comparisons between all three independent measurements yielded a maximum difference of 2% within the central 80% of the field width. For the breast IMRT plan studied, the Pinnacle3 calculations agreed with PRESAGE® measurements to within the ±3%/± 3 mm gamma criterion. This work demonstrates the feasibility of the PRESAGE® to be fashioned into anthropomorphic shape, and establishes the accuracy of Pinnacle3 for breast IMRT. Furthermore, these data have established the groundwork for future investigations into 3D dosimetry with more complex anthropomorphic phantoms.

Keywords: 3D dosimetry, PRESAGE®, IMRT, QA, EBT2 GAFCHROMIC film

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Authors: Réka Sárközi, Péter Iványi, Attila B. Széll

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The aim of this paper is to present the adaptation of the dome construction tool for formex algebra to the parametric design software Grasshopper. Formex algebra is a mathematical system, primarily used for planning structural systems such like truss-grid domes and vaults, together with the programming language Formian. The goal of the research is to allow architects to plan truss-grid structures easily with parametric design tools based on the versatile formex algebra mathematical system. To produce regular structures, coordinate system transformations are used and the dome structures are defined in spherical coordinate system. Owing to the abilities of the parametric design software, it is possible to apply further modifications on the structures and gain special forms. The paper covers the basic dome types, and also additional dome-based structures using special coordinate-system solutions based on spherical coordinate systems. It also contains additional structural possibilities like making double layer grids in all geometry forms. The adaptation of formex algebra and the parametric workflow of Grasshopper together give the possibility of quick and easy design and optimization of special truss-grid domes.

Keywords: parametric design, structural morphology, space structures, spherical coordinate system

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Authors: Ionel Botef

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Studies show that, for qualitative coatings, the knowledge of cold spray technology must focus on a variety of interdisciplinary fields and a framework for problem solving. The integrated disciplines include, but are not limited to, engineering, material sciences, and physics. Due to its importance, the purpose of this paper is to summarize the state of the art of this technology alongside its theoretical and experimental studies, and explore the role and impact of physics upon cold spraying technology.

Keywords: surface engineering, cold spray, physics, modelling

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Authors: А. I. Dovgyalo, S. O. Nekrasova, D. V. Sarmin, A. A. Shimanov, D. A. Uglanov

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Usually liquefied natural gas (LNG) gasification is performed due to atmospheric heat. In order to produce a liquefied gas a sufficient amount of energy is to be consumed (about 1 kW∙h for 1 kg of LNG). This study offers a number of solutions, allowing using a cold energy of LNG. In this paper it is evaluated the application turbines installed behind the evaporator in LNG complex due to its work additional energy can be obtained and then converted into electricity. At the LNG consumption of G=1000kg/h the expansion work capacity of about 10 kW can be reached. Herewith-open Rankine cycle is realized, where a low capacity cryo-pump (about 500W) performs its normal function, providing the cycle pressure. Additionally discussed an application of Stirling engine within the LNG complex also gives a possibility to realize cold energy. Considering the fact, that efficiency coefficient of Stirling engine reaches 50 %, LNG consumption of G=1000 kg/h may result in getting a capacity of about 142 kW of such a thermal machine. The capacity of the pump, required to compensate pressure losses when LNG passes through the hydraulic channel, will make 500 W. Apart from the above-mentioned converters, it can be proposed to use thermoelectric generating packages (TGP), which are widely used now. At present, the modern thermoelectric generator line provides availability of electric capacity with coefficient of efficiency up to 15%. In the proposed complex, it is suggested to install the thermoelectric generator on the evaporator surface is such a way, that the cold end is contacted with the evaporator’s surface, and the hot one – with the atmosphere. At the LNG consumption of G=1000 kgг/h and specified coefficient of efficiency the capacity of the heat flow Qh will make about 32 kW. The derivable net electric power will be P=4,2 kW, and the number of packages will amount to about 104 pieces. The carried out calculations demonstrate the research perceptiveness in this field of propulsion plant development, as well as allow realizing the energy saving potential with the use of liquefied natural gas and other cryogenics technologies.

Keywords: cold energy, gasification, liquefied natural gas, electricity

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Authors: Ekaterina S. Marchenko, Gulsharat A. Baigonakova, Kirill M. Dubovikov, Igor A. Khlusov

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NiTi alloys combine biomechanical and biochemical properties. This makes them a perfect candidate for medical applications. However, there is a serious problem with these alloys, such as the release of Ni from the matrix. Ni ions are known to be toxic to living tissues and leach from the matrix into the surrounding implant tissues due to corrosion after prolonged use. To prevent the release of Ni ions, corrosive strong coatings are usually used. Titanium nitride-based coatings are perfect corrosion inhibitors and also have good bioactive properties. However, there is an opportunity to improve the biochemical compatibility of the surface by depositing another layer. This layer can consist of elements such as calcium and phosphorus. The Ca and P ions form different calcium phosphate phases, which are present in the mineral part of human bones. We therefore believe that these elements must promote osteogenesis and osteointegration. In view of the above, the aim of this study is to investigate the effect of crystallinity on the biocompatibility of a two-layer coating deposited on NiTi substrate by sputtering. The first step of the research, apart from the NiTi polishing, is the layer-by-layer deposition of Ti-Ni-Ti by magnetron sputtering and the subsequent synthesis of this composite in an N atmosphere at 900 °C. The total thickness of the corrosion resistant layer is 150 nm. Plasma assisted RF sputtering was then used to deposit a bioactive film on the titanium nitride layer. A Ca-P powder target was used to obtain such a film. We deposited three types of Ca-P layers with different crystallinity and compared them in terms of cytotoxicity. One group of samples had no Ca-P coating and was used as a control. We obtained different crystallinity by varying the sputtering parameters such as bias voltage, plasma source current and pressure. XRD analysis showed that all coatings are calcium phosphate, but the sample obtained at maximum bias and plasma source current and minimum pressure has the most intense peaks from the coating phase. SEM and EDS showed that all three coatings have a homogeneous and dense structure without cracks and consist of calcium, phosphorus and oxygen. Cytotoxic tests carried out on three types of samples with Ca-P coatings and a control group showed that the control sample and the sample with Ca-P coating obtained at maximum bias voltage and plasma source current and minimum pressure had the lowest number of dead cells on the surface, around 11 ± 4%. Two other types of samples with Ca-P coating have 40 ± 9% and 21 ± 7% dead cells on the surface. It can therefore be concluded that these two sputtering modes have a negative effect on the corrosion resistance of the whole samples. The third sputtering mode does not affect the corrosion resistance and has the same level of cytotoxicity as the control. It can be concluded that the most suitable sputtering mode is the third with maximum bias voltage and plasma source current and minimum pressure.

Keywords: calcium phosphate coating, cytotoxicity, NiTi alloy, two-layer coating

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Authors: Kejal Joshi Reddy, Sirimavo Nair

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Micronutrient malnutrition affects pregnant women and children extremely with reference to growth manifestations in gestation as well as after birth. Early fetal development affected by iodine and iron deficiency leads to poor life quality. Various researchers have found interesting interrelations between iron and iodine. A few studies on impact assessment of DFS supplementation during pregnancy have been reported in India. Aim To provide meaningful contribution by assessing the efficacy of DFS supplementation on iodine and iron status of pregnant women. Design An interventional study. Setting A semi government hospital of urban Vadodara. Subjects Pregnant women (n=150) enrolled during first trimester (< 12 weeks) and followed up till the end of gestation, n=75 were divided in experimental (DFS supplemented) and control (Non supplemented) group. Results Impact on iron and iodine status was assessed by Hb concentration and UIE respectively. Mean Hb improved significantly (p < 0.001) (+0.42 g/dl) in experimental group and reduced non significantly (-0.20 g/dl) in control group at the end, since DFS provided additional 93 mg of iron within 6 months. Median UIE improved non significantly (278.6 to 299.01µg/L) in experimental group and decreased significantly (p < 0.05) (376.59 to 288.66 µg/L) in control group. Conclusion DFS could improve iron and iodine status of experimental group compared to control group. It is an effective measure to control two essential micronutrient deficiencies together.

Keywords: DFS supplementation, anemia, pregnancy, iodine deficiency, iron

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Authors: Sudhanshu Kumar

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Electrical discharge machining, also known as EDM, process is one of the most applicable machining process for removal of material in hard to machine materials like superalloy metals. EDM process utilizes electrical energy into sparks to erode the metals in presence of dielectric medium. In the present investigation, superalloy, Inconel 718 has been selected as workpiece and electrolytic copper as tool electrode. Attempt has been made to understand the effect of size of tool with varying cavity depth during drilling of hole through EDM process. In order to systematic investigate, tool size in terms of tool diameter and cavity depth along with other important electrical parameters namely, peak current, pulse-on time and servo voltage have been varied at three different values and the experiments has been designed using fractional factorial (Taguchi) method. Each experiment has been repeated twice under the same condition in order to understand the variability within the experiments. The effect of variations in parameters has been evaluated in terms of material removal rate, tool wear rate and surface roughness. Results revel that change in tool diameter during machining affects the response characteristics significantly. Larger tool diameter yielded 13% more material removal rate than smaller tool diameter. Analysis of the effect of variation in cavity depth is notable. There is no significant effect of cavity depth on material removal rate, tool wear rate and surface quality. This indicates that number of experiments can be performed to analyze other parameters effect even at smaller depth of cavity which can reduce the cost and time of experiments. Further, statistical analysis has been carried out to identify the interaction effect between parameters.

Keywords: EDM, Inconel 718, material removal rate, roughness, tool wear, tool size

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Authors: Francesca Crivellari, Nicholas Mavrogiannis, Zachary Gagnon

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Portable diagnostic methods have become increasingly important for a number of different purposes: point-of-care screening in developing nations, environmental contamination studies, bio/chemical warfare agent detection, and end-user use for commercial health monitoring. The cheapest and most portable methods currently available are paper-based – lateral flow and dipstick methods are widely available in drug stores for use in pregnancy detection and blood glucose monitoring. These tests are successful because they are cheap to produce, easy to use, and require minimally invasive sampling. While adequate for their intended uses, in the realm of blood-borne pathogens and numerous cancers, these paper-based methods become unreliable, as they lack the nM/pM sensitivity currently achieved by clinical diagnostic methods. Clinical diagnostics, however, utilize techniques involving surface plasmon resonance (SPR) and enzyme-linked immunosorbent assays (ELISAs), which are expensive and unfeasible in terms of portability. To develop a better, competitive biosensor, we must reduce the cost of one, or increase the sensitivity of the other. Electric fields are commonly utilized in microfluidic devices to manipulate particles, biomolecules, and cells. Applications in this area, however, are primarily limited to interfaces formed between immiscible interfaces. Miscible, liquid-liquid interfaces are common in microfluidic devices, and are easily reproduced with simple geometries. Here, we demonstrate the use of electrical fields at liquid-liquid electrical interfaces, known as fluidic dielectrophoresis, (fDEP) for biodetection in a microfluidic device. In this work, we apply an AC electric field across concurrent laminar streams with differing conductivities and permittivities to polarize the interface and induce a discernible, near-immediate, frequency-dependent interfacial tilt. We design this aqueous electrical interface, which becomes the biosensing “substrate,” to be intelligent – it “moves” only when a target of interest is present. This motion requires neither labels nor expensive electrical equipment, so the biosensor is inexpensive and portable, yet still capable of sensitive detection. Nanoparticles, due to their high surface-area-to-volume ratio, are often incorporated to enhance detection capabilities of schemes like SPR and fluorimetric assays. Most studies currently investigate binding at an immobilized solid-liquid or solid-gas interface, where particles are adsorbed onto a planar surface, functionalized with a receptor to create a reactive substrate, and subsequently flushed with a fluid or gas with the relevant analyte. These typically involve many preparation and rinsing steps, and are susceptible to surface fouling. Our microfluidic device is continuously flowing and renewing the “substrate,” and is thus not subject to fouling. In this work, we demonstrate the ability to electrokinetically detect biomolecules binding to functionalized nanoparticles at liquid-liquid interfaces using fDEP. In biotin-streptavidin experiments, we report binding detection limits on the order of 1-10 pM, without amplifying signals or concentrating samples. We also demonstrate the ability to detect this interfacial motion, and thus the presence of binding, using impedance spectroscopy, allowing this scheme to become non-optical, in addition to being label-free.

Keywords: biodetection, dielectrophoresis, microfluidics, nanoparticles

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Authors: Yaofei Jiang, Liangqing Wang, Yanjun Xu

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In recent years, geological explorations have been carried out on the Rumei hydropower station, China. After preliminary analysis of results, the mainly problem of slope in reservoir area is about the stability of accumulation body. It is found that there are 23 accumulations in various sizes in the reservoir area, and most of them are unfavorable geological bodies. Three typical (No. 1, 7, 17) accumulation body slopes were selected as subjects to investigate the stability of the slopes. Take No. 1 accumulation body slope as an example and basic geological condition investigation and formation mechanism analysis were carried out to study the stability and geological analysis of engineering influence of the slope. The accumulation body in the research area distributes along the river with natural slope of 32° ~ 37° which is the natural angle of repose of gravel. The formation mechanism is analyzed based on the composition and structure of the accumulation body. The middle and lower part of the body is dense full of gravel soil mixed with a small amount of sand gravel which is stable. In the upper part, gravel soil is interbedded with bad cemented gravel which as a weak surface is not conducive to slope stability. Under the natural condition before storing water, the underground water level is deep buried, mainly distributed in the bedrock, and the surface and groundwater discharge conditions of the accumulation body are good, which is beneficial to the stability of slope. The safety coefficient calculated by the limit equilibrium method is 1.14, which indicates the slope is basically stable. However, the safety coefficient drops to 1.02 when the normal storage level is 2895m, which is in a dangerous state. The accumulation body will be destabilized by a small-area instability to large-scale or overall instability.

Keywords: accumulation body slope, stability evaluation, geological engineering investigation, effect of storing water

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Authors: Hamd Ahmed

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During the Persian Gulf War in 1991s, The confederation forces were surprised when they were being shot at by friendly forces in Iraqi desert. As obvious was the fact that they were mislead due to the lack of proper guidance and technology resulting in unnecessary loss of life and bloodshed. This unforeseen incident along with many others led the US department of defense to open the doors of GPS. In the very beginning, this technology was for military use, but now it is being widely used and increasingly popular among the public due to its high accuracy and immeasurable significance. The GPS system simply consists of three segments, the space segment (the satellite), the control segment (ground control) and the user segment (receiver). This project work is about designing a 1.57GHZ mixer for triple conversion GPS receiver .The GPS Front-End receiver based on super heterodyne receiver which improves selectivity and image frequency. However the main principle of the super heterodyne receiver depends on the mixer. Many different types of mixers (single balanced mixer, Single Ended mixer, Double balanced mixer) can be used with GPS receiver, it depends on the required specifications. This research project will provide an overview of the GPS system and details about the basic architecture of the GPS receiver. The basic emphasis of this report in on investigating general concept of the mixer circuit some terms related to the mixer along with their definitions and present the types of mixer, then gives some advantages of using singly balanced mixer and its application. The focus of this report is on how to design mixer for GPS receiver and discussing the simulation results.

Keywords: GPS , RF filter, heterodyne, mixer

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Authors: Uluhan Berk Ondul

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This article aims to shed light on the new stage of transitional justice in Argentina through examining the representations of the 2x1 decision of the Supreme Court and Santiago Maldonado’s Disappearance in the newspaper, La Nación. The two events hold the key to understanding Argentina’s journey since return to democracy as they are about the same crimes of the dictatorship, namely, the forced disappearance of civilians and the subsequent impunity that follows. In the case of a convicted torturer, The Supreme Court of Argentina ruled on 3rd of May 2017 that the days spent in preventive detention after two years should be counted double for the overall sentence. This court decision was met with severe resistance from the members of the parliament as well as the human rights movement. The second item on the list still continues and divides the country into two camps: (1) those who think that the police force has committed another act of forced disappearance in the case of activist Santiago Maldonado and (2) the others who blame the peronistas (the party and supporters of the ex-president Cristina Fernandez de Kirchner) of using this subject as a means to score political points. As a newspaper known for its proximity to the current administration, La Nación offers an insight to the direction of the country and also demonstrates how the neoliberal mindset works. The results of the study show that the transitional justice process in Argentina is far from being complete as the Promise of Nunca Más is still not a shared value but a political statement.

Keywords: Argentina, Fallo 2x1, impunity, Santiago Maldonado, transitional justice

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Authors: Alireza Rafieerad, Bushroa Abd Razak, Bahman Nasiri Tabrizi, Jamunarani Vadivelu

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Recently, reports on the fabrication of nanotubular arrays have generated considerable scientific interest, owing to the broad range of applications of the oxide nanotubes in solar cells, orthopedic and dental implants, photocatalytic devices as well as lithium-ion batteries. A more attractive approach for the fabrication of oxide nanotubes with controllable morphology is the electrochemical anodization of substrate in a fluoride-containing electrolyte. Consequently, titanium dioxide nanotubes (TiO2 NTs) have been highly considered as an applicable material particularly in the district of artificial implants. In addition, regarding long-term efficacy and reasons of failing and infection after surgery of currently used dental implants required to enhance the cytocompatibility properties of Ti-based bone-like tissue. As well, graphene oxide (GO) with relevant biocompatibility features in tissue sites, osseointegration and drug delivery functionalization was fully understood. Besides, the boasting antibacterial ability of silver (Ag) remarkably provided for implantable devices without infection symptoms. Here, surface modification of Ti–6Al–7Nb implants (Ti67IMP) by the development of Ag/GO co-decorated TiO2 NTs was examined. Initially, the anodic TiO2 nanotubes obtained at a constant potential of 60 V were annealed at 600 degree centigrade for 2 h to improve the adhesion of the coating. Afterward, the Ag/GO co-decorated TiO2 NTs were developed by spin coating on Ti67IM. The microstructural features, phase composition and wettability behavior of the nanostructured coating were characterized comparably. In a nutshell, the results of the present study may contribute to the development of the nanostructured Ti67IMP with improved surface properties.

Keywords: anodic tio2 nanotube, biomedical applications, graphene oxide, silver, spin coating

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Authors: Nayan Kishore Giri, Ramakar Jha

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Water is a major element for the life of all the mankind in the earth. India’s surface water flows through fourteen major streams. Indian rivers are the main source of potable water in India. In the eastern part of India many toxic hazardous metals discharged into the river from mining industries, which leads many deadly diseases to human being. So the potable water quality is very significant and vital concern at present as it is related with the present and future health perspective of the human race. Consciousness of health risks linked with unsafe water is still very low among the many rural and urban areas in India. Only about 7% of total Indian people using water purifier. This unhealthy situation of water is not only present in India but also present in many underdeveloped countries. The major reason behind this is the high cost of water purifier. This current study geared towards development of economical and efficient technology for the removal of maximum possible toxic metals and pathogen bacteria. The work involves the design of portable purification system and purifying material. In this design Coconut shell granular activated carbon(GAC) and polypropylene filter cloths were used in this system. The activated carbon is impregnated with Iron(Fe). Iron is used because it enhances the adsorption capacity of activated carbon. The thorough analysis of iron impregnated activated carbon(Fe-AC) is done by Scanning Electron Microscope (SEM), X-ray diffraction (XRD) , BET surface area test were done. Then 10 ppm of each toxic metal were infiltrated through the designed purification system and they were analysed in Atomic absorption spectrum (AAS). The results are very promising and it is low cost. This work will help many people who are in need of potable water. They can be benefited for its affordability. It could be helpful in industries and other domestic usage.

Keywords: potable water, coconut shell GAC, polypropylene filter cloths, SEM, XRD, BET, AAS

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Authors: Ehsan Sadie

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Today, the cost of repair and maintenance of structures is very important and by studying the behavior of reinforced concrete structures Will become specified several factors such as : Design and calculation errors, lack of proper implementation of structural changes, the damage caused by the introduction of random loads, concrete corrosion and environmental conditions reduce durability of the structures . Meanwhile building codes alteration also cause changes in the assessment and review of the design and structure rather if necessary will be improved and strengthened in the future.

Keywords: concrete building , expandable cement, honeycombed surface , reinforcement corrosion

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Authors: Ibrahim Hakeem

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Biosolids are stabilised sewage sludge produced from wastewater treatment processes. Biosolids contain valuable plant nutrient which facilitates their beneficial reuse in agricultural land. However, the increasing levels of legacy and emerging contaminants such as heavy metals (HMs), PFAS, microplastics, pharmaceuticals, microbial pathogens etc., are restraining the direct land application of biosolids. Pyrolysis of biosolids can effectively degrade microbial and organic contaminants; however, HMs remain a persistent problem with biosolids and their pyrolysis-derived biochar. In this work, we demonstrated the integrated processing of biosolids involving the acid pre-treatment for HMs removal and selective reduction of ash-forming elements followed by the bench-scale pyrolysis of the treated biosolids to produce quality biochar and bio-oil enriched with valuable platform chemicals. The pre-treatment of biosolids using 3% v/v H₂SO₄ at room conditions for 30 min reduced the ash content from 30 wt% in raw biosolids to 15 wt% in the treated sample while removing about 80% of limiting HMs without degrading the organic matter. The preservation of nutrients and reduction of HMs concentration and mobility via the developed hydrometallurgical process improved the grade of the treated biosolids for beneficial land reuse. The co-removal of ash-forming elements from biosolids positively enhanced the fluidised bed pyrolysis of the acid-treated biosolids at 700 ℃. Organic matter devolatilisation was improved by 40%, and the produced biochar had higher surface area (107 m²/g), heating value (15 MJ/kg), fixed carbon (35 wt%), organic carbon retention (66% dry-ash free) compared to the raw biosolids biochar with surface area (56 m²/g), heating value (9 MJ/kg), fixed carbon (20 wt%) and organic carbon retention (50%). Pre-treatment also improved microporous structure development of the biochar and substantially decreased the HMs concentration and bioavailability by at least 50% relative to the raw biosolids biochar. The integrated process is a viable approach to enhancing value recovery from biosolids.

Keywords: biosolids, pyrolysis, biochar, heavy metals

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Authors: J. O. Idoko, C. N. Michael, T. O. Fasuan

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This study investigated the effects of cooking time, seed-to-water ratio and soaking time on proximate and functional properties of African walnut seed using Box-Behnken design and Response Surface Methodology (BBD-RSM) with a view to increase its utilization in the food industry. African walnut seeds were sorted washed, soaked, cooked, dehulled, sliced, dried and milled. Proximate analysis and functional properties of the samples were evaluated using standard procedures. Data obtained were analyzed using descriptive and inferential statistics. Quadratic models were obtained to predict the proximate and functional qualities as a function of cooking time, seed-to-water ratio and soaking time. The results showed that the crude protein ranged between 11.80% and 23.50%, moisture content ranged between 1.00% and 4.66%, ash content ranged between 3.35% and 5.25%, crude fibre ranged from 0.10% to 7.25% and carbohydrate ranged from 1.22% to 29.35%. The functional properties showed that soluble protein ranged from 16.26% to 42.96%, viscosity ranged from 23.43 mPas to 57 mPas, emulsifying capacity ranged from 17.14% to 39.43% and water absorption capacity ranged from 232% to 297%. An increase in the volume of water used during cooking resulted in loss of water soluble protein through leaching, the length of soaking time and the moisture content of the dried product are inversely related, ash content is inversely related to the cooking time and amount of water used, extraction of fat is enhanced by increase in soaking time while increase in cooking and soaking times result into decrease in fibre content. The results obtained indicated that African walnut could be used in several food formulations as protein supplement and binder.

Keywords: African walnut, functional properties, proximate analysis, response surface methodology

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Authors: Mohammed Titaouine, Toufik Meziane, Kahramen Deghnouche, Hanane Mohamdi, Nabil Mohamdi

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In order to better understand the morphological characters and the zootechniques measures of sheeps races in the in South-East Algeria, a study that was conducted on 1344 heads, taken from 8 farms in different parts of the region, namely T’kout 1, T’kout 2, Tafrent, Barika, Sidi-Okba, Biskra, Ouled-Djellal and Msila. The results from the present study showed significant differences in the group of 14 morphological studied variables, the body length is the most important variable. Reproduction performance of 160 ewes and growth performances of 56 lambs were analysed. The analyses of the data showed that the ewes have a fertility level of 69%, a prolificacy level of 114% and a fecundity level of 79%. Lambs weigh 3.5kg at birth, 9.38kg at 30d, 13.45kg at 60d, 16.91kg at 90d and 21.51 kg at 120d. The speed of the growth level 0.20kg/d from birth to 30d, 0.14 kg/d between 30d and 60d, 0.12kg/d between 60d and 90d and 0.15kg/d between 90d and 120d. The simple born lambs were more heavy than the double born lambs. By contrast, sex was not significant for all the variables except the weight at 60d, the birth month has a significant effect on the weight at birth, at 30d, at 60d and it was no significant for the weight at 90d and at 120d.The flocks born on September, October, November, and December were more heavy than the flocks born on January, February, and March.

Keywords: morphological characterization, reproduction performance, growth performances, algeria

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Authors: Oluwafemi Babatunde Oduntan, Isaac A. Bamgboye

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The solid waste disposal and its management from pineapple juice processing constitute environmental contamination affecting public health. The use of this by-product called pomace has potentials to reduce cost of aquafeed. Pineapple pomace collected after juice extraction was dried and milled. The interactive effects of feeding rate (1.28, 1.44 and 1.60kg/min), screw speed (305, 355 and 405rpm), moisture content (16, 19 and 22%), temperatures (60, 80, 100 and 120°C), cutting speed (1300, 1400 and 1500rpm), pomace inclusion ratio (5, 10, 15, 20%) and open surface die (50, 75 and 100%) on the extrudate physical properties (bulk density, unit density, expansion ratio, durability and floatability) were investigated using optimal custom design (OCD) matrix and response surface methodology. The predicted values were found to be in good agreement with the experimental values for, expansion ratio, durability and floatability (R2 = 0.7970; 0.9264; 0.9098 respectively) with the exceptions of unit density and bulk density (R2 = 0.1639; 0.2768 respectively). All the extrudates showed relatively high floatability, durability. The inclusion of pineapple pomace produced less expanded and more compact textured extrudates. Results indicated that increased in the value of pineapple pomace, screw speed, feeding rate decreased unit density, bulk density, expansion ratio, durability and floatability of the extrudate. However, increasing moisture content of feed mash resulted in increase unit density and bulk density. Addition of extrusion temperature and cutting speed increased the floatability and durability of extrudate. The proportion of pineapple pomace in aquafeed extruded product was observed to have significantly lower effect on the selected responses.

Keywords: aquafeed, extrusion, physical properties, pineapple pomace, waste

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Authors: Cherish Romina Prajitno, Sunisa Thaichinda

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One indicator of facial aging is wrinkles. Not only that, but wrinkles are a key indicator in our world of facial aesthetics. Wrinkles occur where fault lines develop in aging skin. Nowadays, people are more motivated to keep up their appealing and young appearance. Many individuals are seeking a fast recovery time for their aesthetic procedures and are interested in non-invasive techniques that have a proven track record for successful outcomes. The purpose of this study is to see the efficacy of 100% (pure) grapeseed oil for reducing periorbital wrinkles. This study used the split-face, double-blind method, and this treatment was administered for three months at random to fifteen patients, with the grapeseed oil at one side of the face and the other side with the placebo. The main outcome measure was determined by conducting a comparative analysis of the participants' wrinkle results during each visit using the VIsioscan® VC98. Additionally, we evaluated the skin's elasticity and barrier function using the Cutometer® MP 530 and Tewameter® TM300. Furthermore, we administered a satisfaction score questionnaire to the patients in the 12th week. The findings of the study indicate that grapeseed oil exhibited a noteworthy effect in diminishing the appearance of wrinkles in the periorbital region, enhancing the viscoelastic properties of the periorbital skin, and improving the functionality of the skin barrier in the periorbital area.

Keywords: periorbital wrinkles, pure grapeseed oil, split-face method

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Authors: H. Z. M. Chong, M. E. Y. Leong, G. L. Khor, S. C. Loke

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Vitamin D insufficiency is reported to be prevalent among women living in different altitudes including the equator where sunshine is available throughout the year. Multiple factors for vitamin D insufficiency include poor intake of vitamin D rich food and inadequate sun exposure, especially among women working indoor with a sedentary lifestyle. Furthermore, Muslim women in Malaysia whose attire covers the entire body are likely to receive poor sun exposure. This research determined serum vitamin D status, vitamin D intake and sun exposure of women aged 20-45 years of different ethnicity in Kuala Lumpur, Malaysia. Blood samples were collected from 106 women for determination of serum 25(OH)D levels. Information about vitamin D intake and sun exposure were obtained by interviewing the subjects using pre-tested questionnaires. The overall mean serum 25(OH)D was found to be 29.9 ± 14 nmol/L. Vitamin D deficiency and insufficiency was prevalent and highest among the Malay women. Less than ten percent of the subjects in this study met the sufficient vitamin D level recommendation of ≥50 nmol/L. Intake of vitamin D rich food such as oily fishes was poor across the different ethnicity. Other dietary sources of vitamin D in the diet were fortified bread and skim milk. On the other hand, the median sunlight exposure of the subjects was 3.9 hours per week. The Malay women reported to have the highest duration being exposed to the sun. Nevertheless, due to cultural clothing practices, these women had the least body surface area exposed to sunlight, resulting in the lowest calculated sun index score compared to the Chinese and the Indians. Low intake of vitamin D rich foods and sun exposure were negatively correlated with serum 25(OH)D level. In conclusion, intake of food sources rich in vitamin D and adequate body surface area exposed to the sun are essential to ensure healthy vitamin D level. Supplementation of vitamin D may be recommended to women whom unable to meet these recommendations.

Keywords: serum 25-OH, sun exposure, vitamin D food frequency, vitamin D deficiency

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Authors: Tania Camarillo Contreras, Yana Kuchirko

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Women’s sexuality, despite it being a core part of human functioning, has historically been stigmatized, silenced, and regulated and silenced across many cultures. The regulation of women’s bodies and desires has often been accomplished via gender ideologies and norms that ascribe power to men over women. Within Latino communities, gender ideologies like marianismo provide scripts by which women are expected to adhere submissiveness, purity, and putting others’ needs before their own. Prior work on sexuality-related topics among Latinas has almost exclusively examined the roles of risky behavior, partner violence, and gender roles on psychological and health outcomes. it know little about positive aspects of Latinas’ sexuality, such as their perspectives on sexual excitation and inhibition. Moreover, we know little about Latina’s sexuality in relation to marianismo. In this study, it ask the following questions (1) What are Latina’s perspectives on sexual excitation/inhibition? Do they vary by demographic variables (e.g., education, religiosity); (2) Does endorsement of marianismo among Latina women predict their perspectives on sexual excitation/sexual inhibition? and (3) Does endorsement of double standard (mediator variable) mediate the relation between marianismo (Independent) and sexual excitation/sexual inhibition? The results of this study shed light on effects of culturally specific gender ideologies like marianismo on women’s sexualities and have implications for culturally informed and gender-affirming policies seeking to better support Latinas’ sexual health.

Keywords: cultural beliefs, latinas, marianismo, sexuality, sexual inhibition

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Authors: Eman Ghoneim

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The Arabian deserts include some of the driest areas on Earth. Yet, its landforms reserved a record of past wet climates. During humid phases, the desert was green and contained permanent rivers, inland deltas and lakes. Some of their water would have seeped and replenished the groundwater aquifers. When the wet periods came to an end, several thousand years ago, the entire region transformed into an extended band of desert and its original fluvial surface was totally covered by windblown sand. In this work, radar and thermal infrared images were used to reveal numerous hidden surface/subsurface features. Radar long wavelength has the unique ability to penetrate surface dry sands and uncover buried subsurface terrain. Thermal infrared also proven to be capable of spotting cooler moist areas particularly in hot dry surfaces. Integrating Radarsat images and GIS revealed several previously unknown paleoriver and lake basins in the region. One of these systems, known as the Kufrah, is the largest yet identified river basin in the Eastern Sahara. This river basin, which straddles the border between Egypt and Libya, flowed north parallel to the adjacent Nile River with an extensive drainage area of 235,500 km2 and massive valley width of 30 km in some parts. This river was most probably served as a spillway for an overflow from Megalake Chad to the Mediterranean Sea and, thus, may have acted as a natural water corridor used by human ancestors to migrate northward across the Sahara. The Gilf-Kebir is another large paleoriver system located just east of Kufrah and emanates from the Gilf Plateau in Egypt. Both river systems terminate with vast inland deltas at the southern margin of the Great Sand Sea. The trends of their distributary channels indicate that both rivers drained to a topographic depression that was periodically occupied by a massive lake. During dry climates, the lake dried up and roofed by sand deposits, which is today forming the Great Sand Sea. The enormity of the lake basin provides explanation as to why continuous extraction of groundwater in this area is possible. A similar lake basin, delimited by former shorelines, was detected by radar space data just across the border of Sudan. This lake, called the Northern Darfur Megalake, has a massive size of 30,750 km2. These former lakes and rivers could potentially hold vast reservoirs of groundwater, oil and natural gas at depth. Similar to radar data, thermal infrared images were proven to be useful in detecting potential locations of subsurface water accumulation in desert regions. Analysis of both Aster and daily MODIS thermal channels reveal several subsurface cool moist patches in the sandy desert of the Arabian Peninsula. Analysis indicated that such evaporative cooling anomalies were resulted from the subsurface transmission of the Monsoonal rainfall from the mountains to the adjacent plain. Drilling a number of wells in several locations proved the presence of productive water aquifers confirming the validity of the used data and the adopted approaches for water exploration in dry regions.

Keywords: radarsat, SRTM, MODIS, thermal infrared, near-surface water, ancient rivers, desert, Sahara, Arabian peninsula

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Authors: Oktia Woro Kasmini Handayani, Sri Ratna Rahayu, Efa Nugroho, Bertakalswa Hermawati

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The double burden of nutrition problem must be faced by Indonesia as developing country. The implemented program did not improve the nutritional status, therefore need to consider to utilize local potential. The objective of this research was to find out the effectivity of magnification model of early detect through local potential utilization in urban region, Semarang, Central Java, Indonesia. The research used an experimental design with the quantitative-qualitative approach. The population was all toddlers under five within the research region, sample determination by purposive sampling, as many as 216 toddlers. Quantitative data analysis used effectively criteria by Sugiono. Qualitative data was analyzed using NVivo. The optimization of local potential in the effort of nutrition status improvement shows number of nutrition case found was increased 225% (very effective), number of cases treated was increased 175% (very effective), number of cases counselled was increased 200% (effective), and number of cases that have improvement increase 75% (effective). The local potential need to be utilized in the effort of nutrition program improvement one of it is through the community empowerment, particularly health care and health high education institution as partner.

Keywords: early detection, nutrition status, local potential, health cadre

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Authors: Dhaivat S. Soni, Snehal Thakor, Afroz Bhatti

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The prepare CNTs in bulk quantity by as easiest as possible method with highly pure and small diameter. Prepared CNTs first charactered its structural parameter for the conformation of CNTs and purity. Surface morphology of CNTs stured by using various instruments finally study application of prepared CNTs in various field. Carbon nanotubes (CNTs) were synthesized in large scale by pyrolyzing activated carbon in sealed autoclaves.

Keywords: nanostructures, nanotubes, carbon, pyrolysis

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Authors: A. Schirru, A. Irimescu, S. Merola, A. d’Adamo, S. Fontanesi

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One of the aspects that are usually neglected during the design phase of an engine is the effect of the spark plug on the flow field inside the combustion chamber. Because of the difficulties in the experimental investigation of the mutual interaction between flow alteration and early flame kernel convection effect inside the engine combustion chamber, CFD-3D simulation is usually exploited in such cases. Experimentally speaking, a particular type of engine has to be used in order to directly observe the flame propagation process. In this study, a double electrode spark plug was fitted into an optically accessible engine and a high-speed camera was used to capture the initial stages of the combustion process. Both the arc and the kernel phases were observed. Then, a morphologic analysis was carried out and the position of the center of mass of the flame, relative to the spark plug position, was calculated. The crossflow orientation was chosen for the spark plug and the kernel growth process was observed for different air-fuel ratios. It was observed that during a normal cycle the flow field between the electrodes tends to transport the arc deforming it. Because of that, the kernel growth phase takes place away from the electrodes and the flame propagates with a preferential direction dictated by the flow field.

Keywords: Combustion, Optically Accessible Engine, Spark-Ignition Engine, Sparl Orientation, Kernel Growth

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Authors: Mumuni Sumaila, Viness Pillay, Yahya E. Choonara, Pradeep Kumar, Pierre P. Kondiah

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Tuberculosis (TB) remains a serious challenge to public health globally, despite every effort put together to curb the disease. Current TB therapeutics available have proven to be inefficient due to a multitude of drawbacks that range from serious adverse effects/drug toxicity to inconsistent bioavailability, which ultimately contributes to the emergence of drug-resistant TB. An effective ‘cargo’ system designed to cleverly deliver therapeutic doses of anti-TB drugs to infection sites and in a sustained-release manner may provide a better therapeutic choice towards winning the war against TB. In the current study, we investigated mannose-functionalized lipopolysaccharide hybrid nanoparticles for safety and efficacy towards macrophage-targeted simultaneous delivery of the two first-line anti-TB drugs, rifampicin (RF) and isoniazid (IS). RF-IS-loaded lipopolysaccharide hybrid nanoparticles were fabricated using the solvent injection technique (SIT), incorporating soy lecithin (SL) and low molecular weight chitosan (CS) as the lipid and polysaccharide components, respectively. Surface-functionalized nanoparticles were obtained through the reaction of the aldehyde group of mannose with free amine functionality present at the surface of the nanoparticles. The functionalized nanocarriers were spherical with average particle size and surface charge of 107.83 nm and +21.77 mV, respectively, and entrapment efficiencies (EE) were 53.52% and 69.80% for RF and IS, respectively. FTIR spectrum revealed high-intensity bands between 1663 cm⁻¹ and 1408 cm⁻¹ wavenumbers (absent in non-functionalized nanoparticles), which could be attributed to the C=N stretching vibration produced by the formation of Schiff’s base (–N=CH–) during the mannosylation reaction. In vitro release studies showed a sustained-release profile for RF and IS, with less than half of the total payload released over a 48-hour period. The nanocarriers were biocompatible and safe, with more than 80% cell viability achieved when incubated with RAW 264.7 cells at concentrations 30 to 500 μg/mL over a 24-hour period. Cellular uptake studies (after a 24-hour incubation period with the murine macrophage cells, RAW 264.7) revealed a 13- and a 9-fold increase in intracellular accumulation of RF and IS, respectively, when compared with the unformulated RF+IS solution. A 6- and a 3-fold increase in intracellular accumulation of RF and IS, respectively, were observed when compared with the non-functionalized nanoparticles. Furthermore, fluorescent microscopy images showed nanoparticle internalization and accumulation within the RAW 264.7 cells, which was more significant in the mannose-functionalized system compared to the non-functionalized nanoparticles. The overall results suggested that the fabricated mannose-functionalized lipopolysaccharide nanoparticles are a safe and promising platform for macrophage-targeted delivery of anti-TB therapeutics. However, in vivo pharmacokinetic/pharmacodynamics studies are required to further substantiate the therapeutic efficacy of the nanosystem.

Keywords: anti-tuberculosis therapeutics, hybrid nanosystem, lipopolysaccharide nanoparticles, macrophage-targeted delivery

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Authors: T. Sakamoto, S. Kainuma

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Firstly, in order to examine the influence of the remaining amount of the rust on the coating film durability, the accelerated deterioration tests were carried out. In order to prepare test specimens, uncoated steel plates were corroded by the Salt Spray Test (SST) prior to the accelerated deterioration tests, and then the prepared test specimens were coated by epoxy resin and phthalic acid resin each of which has different gas-barrier performance. As the result, it was confirmed that the under-film corrosion occurred in the area and the adjacency to great quantities of salt exists in the rust, and did not occurred in the specimen which was applied the epoxy resin paint after the surface preparation by the power tool. Secondly, in order to clarify the influence of the corrosive factors on the coating film durability, outdoor exposure tests were conducted for one year on actual steel bridge located at a coastal area. The tests specimens consist of coated corroded plates and the uncoated steel plates, and they were installed on the different structural members of the bridge for one year. From the test results, the uncoated steel plates which were installed on the underside of the member are easily corrosive and had highly correlation with the amount of salt in the rust. On the other hand, the most corrosive under-film steel was the vertical surface of the web plate. Thus, it was confirmed that under-film corrosion rate was not match with corrosion rate of the uncoated steel. Consequently, it is estimated that the main factors of under-film corrosion are gas-barrier property of coating film and corrosive factors such as water vapor and temperature. The salt which significantly corrodes the uncoated steel plate is not directly related to the under-film corrosion.

Keywords: accelerated deterioration test, coating durability, environmental factor, under-film corrosion

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Authors: Hossein Tavallali, Mohammad Ali Karimi, Gohar Deilamy-Rad

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In this study, a new type of alumina-coated magnetite nanoparticles (Fe3O4/Al2O3 NPs) with sodium dodecyl sulfate- 1-(2-pyridylazo)-2-naphthol (SDS-PAN) as a new sorbent solid phase extraction (SPE) has been successfully synthesized and applied for preconcentration and separation of Cd and Pb in environmental samples. Compared with conventional SPE methods, the advantages of this new magnetic Mixed Hemimicelles Solid-Phase Extraction Procedure (MMHSPE) still include easy preparation and regeneration of sorbents, short times of sample pretreatment, high extraction yields, and high breakthrough volumes. It shows great analytical potential in preconcentration of Cd and Pb compounds from large volume water samples. Due to the high surface area of these new sorbents and the excellent adsorption capacity after surface modification by SDS-PAN, satisfactory concentration factor and extraction recoveries can be produced with only 0.05 g Fe3O4/Al2O3 NPs. The metals were eluted with 3mL HNO3 2 mol L-1 directly and detected with the detection system Flame Atomic Absorption Spectrometry (FAAS). Various influencing parameters on the separation and preconcentration of trace metals, such as the amount of PAN, pH value, sample volume, standing time, desorption solvent and maximal extraction volume, amount of sorbent and concentration of eluent, were studied. The detection limits of this method for Cd and Pb were 0.3 and 0.7 ng mL−1 and the R.S.D.s were 3.4 and 2.8% (C = 28.00 ng mL-1, n = 6), respectively. The preconcentration factor of the modified nanoparticles was 166.6. The proposed method has been applied to the determination of these metal ions at trace levels in soil, river, tap, mineral, spring and wastewater samples with satisfactory results.

Keywords: Alumina-coated magnetite nanoparticles, Magnetic Mixed Hemimicell Solid-Phase Extraction, Cd and Pb, soil sample

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