Search results for: nuclear fuel cycle
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 4275

Search results for: nuclear fuel cycle

1215 The Relationship between Operating Condition and Sludge Wasting of an Aerobic Suspension-Sequencing Batch Reactor (ASSBR) Treating Phenolic Wastewater

Authors: Ali Alattabi, Clare Harris, Rafid Alkhaddar, Ali Alzeyadi

Abstract:

Petroleum refinery wastewater (PRW) can be considered as one of the most significant source of aquatic environmental pollution. It consists of oil and grease along with many other toxic organic pollutants. In recent years, a new technique was implemented using different types of membranes and sequencing batch reactors (SBRs) to treat PRW. SBR is a fill and draw type sludge system which operates in time instead of space. Many researchers have optimised SBRs’ operating conditions to obtain maximum removal of undesired wastewater pollutants. It has gained more importance mainly because of its essential flexibility in cycle time. It can handle shock loads, requires less area for operation and easy to operate. However, bulking sludge or discharging floating or settled sludge during the draw or decant phase with some SBR configurations are still one of the problems of SBR system. The main aim of this study is to develop and innovative design for the SBR optimising the process variables to result is a more robust and efficient process. Several experimental tests will be developed to determine the removal percentages of chemical oxygen demand (COD), Phenol and nitrogen compounds from synthetic PRW. Furthermore, the dissolved oxygen (DO), pH and oxidation-reduction potential (ORP) of the SBR system will be monitored online to ensure a good environment for the microorganisms to biodegrade the organic matter effectively.

Keywords: petroleum refinery wastewater, sequencing batch reactor, hydraulic retention time, Phenol, COD, mixed liquor suspended solids (MLSS)

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1214 Relation of Black Carbon Aerosols and Atmospheric Boundary Layer Height during Wet Removal Processes over a Semi Urban Location

Authors: M. Ashok Williams, T. V. Lakshmi Kumar

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The life cycle of Black carbon aerosols depends on their physical removal processes from the atmosphere during the precipitation events. Black Carbon (BC) mass concentration has been analysed during rainy and non-rainy days of Northeast (NE) Monsoon months of the years 2015 and 2017 over a semi-urban environment near Chennai (12.81 N, 80.03 E), located on the east coast of India. BC, measured using an Aethalometer (AE-31) has been related to the atmospheric boundary layer height (BLH) obtained from the ERA Interim Reanalysis data during rainy and non-rainy days on monthly mean basis to understand the wet removal of BC over the study location. The study reveals that boundary layer height has a profound effect on the BC concentration on rainy days and non rainy days. It is found that the BC concentration in the night time is lower on rainy days compared to non rainy days owing to wash out on rainy days and the boundary layer height remaining nearly the same on rainy and non rainy days. On the other hand, in the daytime, it is found that the BC concentration remains nearly the same on rainy and non rainy days whereas the boundary layer height is lower on rainy days compared to non rainy days. This reveals that in daytime, lower boundary layer heights compensate for the wet removal effect on BC concentration on rainy days. A quantitative relation is found between the product of BC and BLH during rainy and non-rainy days which indicates the extent of redistribution of BC during non-rainy days when compared to the rainy days. Further work on the wet removal processes of the BC is in progress considering the individual rain events and other related parameters like wind speed.

Keywords: black carbon aerosols, atmospheric boundary layer, scavenging processes, tropical coastal location

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1213 Mathematical Analysis of Variation in Inlet Shock Wave Angle on Specific Impulse of Scramjet Engine

Authors: Shrikant Ghadage

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Study of shock waves generated in the Scramjet engine is typically restricted to pressure, temperature, density, entropy and Mach number variation across the shock wave. The present work discusses the impact of inlet shock wave angles on the specific impulse of the Scramjet engine. A mathematical analysis has done for the isentropic hypersonic flow of air flowing through a Scramjet with hydrogen fuel at an altitude of 30 km. Analysis has been done in order to get optimum shock wave angle to achieve maximum impulse. Since external drag has excluded from the analysis, the losses due to friction are not considered for the present analysis. When Mach number of the airflow at the entry of the nozzle reaches unity, then that flow is choked. This condition puts limitations on increasing the inlet shock wave angle. As inlet shock wave angle increases, speed of the flow entering into the nozzle decreases, which results in an increase in the specific impulse of the engine. When the speed of the flow at the entry of the nozzle reduces below sonic speed, then there is no further increase in the specific impulse of the engine. Here the Conclusion is the thrust and specific impulse of a scramjet engine, which increases gradually with an increase in inlet shock wave angle up to the condition when airflow speed reaches sonic velocity at the exit of the combustor. In addition to that, variation in drag force at the inlet of the scramjet and variation in hypersonic flow conditions at every stage of the scramjet also studied in order to understand variation on flow characteristics with respect to flow deflection angle. Essentially, it helps in designing inlet profile for the Scramjet engine to achieve optimum specific impulse.

Keywords: hypersonic flow, scramjet, shock waves, specific impulse, mathematical analysis

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1212 Neo-Adjuvant B-CAT Chemotherapy in Triple Negative Breast Cancer

Authors: Muneeb Nasir, Misbah Masood, Farrukh Rashid, Abubabakar Shahid

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Introduction: Neo-adjuvant chemotherapy is a potent option for triple negative breast cancer (TNBC) as these tumours lack a clearly defined therapeutic target. Several recent studies lend support that pathological complete remission (pCR) is associated with improved disease free survival (DFS) and overall survival (OS) and could be used as surrogate marker for DFS and OS in breast cancer patients. Methods: We have used a four-drug protocol in T3 and T4 TNBC patients either N+ or N- in the neo-adjuvant setting. The 15 patients enrolled in this study had a median age of 45 years. 12 patients went on to complete four planned cycles of B-CAT protocol. The chemotherapy regimen included inj. Bevacizumab 5mg/kg D1, inj. Adriamycin 50mg/m2 D1 and Docetaxel 65mg/m2 on D1. Inj. Cisplatin 60mg/m2 on D2. All patients received GCF support from D4 to D9 of each cycle. Results: Radiological assessment using ultrasound and PET-CT revealed a high percentage of responses. Radiological CR was documented in half of the patients (6/12) after four cycles. Remaining patients went on to receive 2 more cycles before undergoing radical surgery. pCR was documented in 7/12 patients and 3 more had a good partial response. The regimen was toxic and grade ¾ neutropenia was seen in 58% of patients. Four episodes of febrile neutropenia were reported and managed. Non-hematatological toxicities were common with mucositis, diarrhea, asthenia and neuropathy topping the list. Conclusion: B-CAT is a very active combination with very high pCR rates in TNBC. Toxicities though frequent, were manageable on outpatient basis. This protocol warrants further investigation.

Keywords: B-CAT:bevacizumab, cisplatin, adriamycin, taxotere, CR: complete response, pCR: pathological complete response, TNBC: triple negative breast cancer

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1211 The Roles of Muslims Scholars in Minifying Religious Extremism for Religious Tolerance and Peace Building in Nigeria

Authors: Mukhtar Sarkin-Kebbi

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Insurgency, religious extremism and other related religious crises become hydra-headed in Nigeria, which caused destruction of human lives and properties worth of billions naira. As result, millions people were displaced and million children were out of school most of whom from Muslims community. The wrong teaching and misinterpretation of Islam by some Muslim community fuel the spread of extremist ideology hatred among Muslim sects, non-Muslims and emergency of extremist groups, like Boko Haram. A multi-religious country like Nigeria to realise its development in all human aspects, there must be unity and religious tolerance. Many agreed that changing the ideologies of insurgents and religious extremism will require intellectual role with vigorous campaign. Muslim scholars can play a vital role in promoting social reform and peaceful coexistence. This paper discusses the importance of unity among Muslim community and religious tolerance in light of the Qur’an and the Hadith. The paper also reviews the relationship between Muslims and non Muslims during the life time the Prophet (S.A.W.) in order to serve as exemplary model. Contemporary issues such as religious extremism, sectarians, intolerance and their consequences were examined. To minify religious intolerance and extremism,the paper identifies the roles to be played by Muslim scholars with references from Qur’an and Sunnah. The paper concludes that to realise overall human development and eternal salvation, Muslim should shun away from any religious crises and embrace unity and religious tolerance. Finally the paper recommends among others that only pious and learned scholars should be allowed to preach in any religious gathering, Muslim should exercise patience, tolerance in dealing with Muslims and non Muslims. Muslims should leave by example from the teaching of Qur’an and Sunnah of the Prophet (S.A.W.).

Keywords: Muslim scholars, peace building, religious extremism, religious tolerance

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1210 Study and Solving High Complex Non-Linear Differential Equations Applied in the Engineering Field by Analytical New Approach AGM

Authors: Mohammadreza Akbari, Sara Akbari, Davood Domiri Ganji, Pooya Solimani, Reza Khalili

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In this paper, three complicated nonlinear differential equations(PDE,ODE) in the field of engineering and non-vibration have been analyzed and solved completely by new method that we have named it Akbari-Ganji's Method (AGM) . As regards the previous published papers, investigating this kind of equations is a very hard task to do and the obtained solution is not accurate and reliable. This issue will be emerged after comparing the achieved solutions by Numerical Method. Based on the comparisons which have been made between the gained solutions by AGM and Numerical Method (Runge-Kutta 4th), it is possible to indicate that AGM can be successfully applied for various differential equations particularly for difficult ones. Furthermore, It is necessary to mention that a summary of the excellence of this method in comparison with the other approaches can be considered as follows: It is noteworthy that these results have been indicated that this approach is very effective and easy therefore it can be applied for other kinds of nonlinear equations, And also the reasons of selecting the mentioned method for solving differential equations in a wide variety of fields not only in vibrations but also in different fields of sciences such as fluid mechanics, solid mechanics, chemical engineering, etc. Therefore, a solution with high precision will be acquired. With regard to the afore-mentioned explanations, the process of solving nonlinear equation(s) will be very easy and convenient in comparison with the other methods. And also one of the important position that is explored in this paper is: Trigonometric and exponential terms in the differential equation (the method AGM) , is no need to use Taylor series Expansion to enhance the precision of the result.

Keywords: new method (AGM), complex non-linear partial differential equations, damping ratio, energy lost per cycle

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1209 Recovery of Au and Other Metals from Old Electronic Components by Leaching and Liquid Extraction Process

Authors: Tomasz Smolinski, Irena Herdzik-Koniecko, Marta Pyszynska, M. Rogowski

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Old electronic components can be easily found nowadays. Significant quantities of valuable metals such as gold, silver or copper are used for the production of advanced electronic devices. Old useless electronic device slowly became a new source of precious metals, very often more efficient than natural. For example, it is possible to recover more gold from 1-ton personal computers than seventeen tons of gold ore. It makes urban mining industry very profitable and necessary for sustainable development. For the recovery of metals from waste of electronic equipment, various treatment options based on conventional physical, hydrometallurgical and pyrometallurgical processes are available. In this group hydrometallurgy processes with their relatively low capital cost, low environmental impact, potential for high metal recoveries and suitability for small scale applications, are very promising options. Institute of Nuclear Chemistry and Technology has great experience in hydrometallurgy processes especially focused on recovery metals from industrial and agricultural wastes. At the moment, urban mining project is carried out. The method of effective recovery of valuable metals from central processing units (CPU) components has been developed. The principal processes such as acidic leaching and solvent extraction were used for precious metals recovery from old processors and graphic cards. Electronic components were treated by acidic solution at various conditions. Optimal acid concentration, time of the process and temperature were selected. Precious metals have been extracted to the aqueous phase. At the next step, metals were selectively extracted by organic solvents such as oximes or tributyl phosphate (TBP) etc. Multistage mixer-settler equipment was used. The process was optimized.

Keywords: electronic waste, leaching, hydrometallurgy, metal recovery, solvent extraction

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1208 Understanding Chromosome Movement in Starfish Oocytes

Authors: Bryony Davies

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Many cell and tissue culture practices ignore the effects of gravity on cell biology, and little is known about how cell components may move in response to gravitational forces. Starfish oocytes provide an excellent model for interrogating the movement of cell components due to their unusually large size, ease of handling, and high transparency. Chromosomes from starfish oocytes can be visualised by microinjection of the histone-H2B-mCherry plasmid into the oocytes. The movement of the chromosomes can then be tracked by live-cell fluorescence microscopy. The results from experiments using these methods suggest that there is a replicable downward movement of centrally located chromosomes at a median velocity of 0.39 μm/min. Chromosomes nearer the nuclear boundary showed more restricted movement. Chromosome density and shape could also be altered by microinjection of restriction enzymes, primarily Alu1, before imaging. This was found to alter the speed of chromosome movement, with chromosomes from Alu1-injected nuclei showing a median downward velocity of 0.60 μm/min. Overall, these results suggest that there is a non-negligible movement of chromosomes in response to gravitational forces and that this movement can be altered by enzyme activity. Future directions based on these results could interrogate if this observed downward movement extends to other cell components and to other cell types. Additionally, it may be important to understand whether gravitational orientation and vertical positioning of cell components alter cell behaviour. The findings here may have implications for current cell culture practices, which do not replicate cell orientations or external forces experienced in vivo. It is possible that a failure to account for gravitational forces in 2D cell culture alters experimental results and the accuracy of conclusions drawn from them. Understanding possible behavioural changes in cells due to the effects of gravity would therefore be beneficial.

Keywords: starfish, oocytes, live-cell imaging, microinjection, chromosome dynamics

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1207 Establishing Sequence Stratigraphic Framework and Hydrocarbon Potential of the Late Cretaceous Strata: A Case Study from Central Indus Basin, Pakistan

Authors: Bilal Wadood, Suleman Khan, Sajjad Ahmed

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The Late Cretaceous strata (Mughal Kot Formation) exposed in Central Indus Basin, Pakistan is evaluated for establishing sequence stratigraphic framework and potential of hydrocarbon accumulation. The petrographic studies and SEM analysis were carried out to infer the hydrocarbon potential of the rock unit. The petrographic details disclosed 4 microfacies including Pelagic Mudstone, OrbitoidalWackestone, Quartz Arenite, and Quartz Wacke. The lowermost part of the rock unit consists of OrbitoidalWackestone which shows deposition in the middle shelf environment. The Quartz Arenite and Quartz Wacke suggest deposition on the deep slope settings while the Pelagic Mudstone microfacies point toward deposition in the distal deep marine settings. Based on the facies stacking patterns and cyclicity in the chronostratigraphic context, the strata is divided into two 3rd order cycles. One complete sequence i.e Transgressive system tract (TST), Highstand system tract (HST) and Lowstand system tract (LST) are again replaced by another Transgressive system tract and Highstant system tract with no markers of sequence boundary. The LST sands are sandwiched between TST and HST shales but no potential porosity/permeability values have been determined. Microfacies and SEM studies revealed very fewer chances for hydrocarbon accumulation and overall reservoir potential is characterized as low.

Keywords: cycle, deposition, microfacies, reservoir

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1206 Economic Evaluation of Varying Scenarios to Fulfill the Regional Electricity Demand in Pakistan

Authors: Muhammad Shahid, Kafait Ullah, Kashif Imran, Arshad Mahmood, Maarten Arentsen

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Poor planning and governance in the power sector of Pakistan have generated several issues ranging from gradual reliance on thermal-based expensive energy mix, supply shortages, unrestricted demand, subsidization, inefficiencies at different levels of the value chain and resultantly, the circular debt. This situation in the power sector has also hampered the growth of allied economic sectors. This study uses the Long-range Energy Alternative Planning (LEAP) system for electricity modelling of Pakistan from the period of 2016 to 2040. The study has first time in Pakistan forecasted the electricity demand at the provincial level. At the supply side, five scenarios Business as Usual Scenario (BAUS), Coal Scenario (CS), Gas Scenario (GS), Nuclear Scenario (NS) and Renewable Scenario (RS) have been analyzed based on the techno-economic and environmental parameters. The study has also included environmental externality costs for evaluating the actual costs and benefits of different scenarios. Contrary to the expectations, RS has a lower output than even BAUS. The study has concluded that the generation from RS has five times lesser costs than BAUS, CS, and GS. NS can also be an alternative for the sustainable future of Pakistan. Generation from imported coal is not a good option, however, indigenous coal with clean coal technologies should be promoted. This paper proposes energy planners of the country to devise incentives for the utilization of indigenous energy resources including renewables on priority and then clean coal to reduce the energy crises of Pakistan.

Keywords: economic evaluation, externality cost, penetration of renewable energy, regional electricity supply-demand planning

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1205 Studies on the Use of Sewage Sludge in Agriculture or in Incinerators

Authors: Catalina Iticescu, Lucian Georgescu, Mihaela Timofti, Dumitru Dima, Gabriel Murariu

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The amounts of sludge resulting from the treatment of domestic and industrial wastewater can create serious environmental problems if no solutions are found to eliminate them. At present, the predominant method of sewage sludge disposal is to store and use them in agricultural applications. The sewage sludge has fertilizer properties and can be used to enrich agricultural soils due to the nutrient content. In addition to plant growth (nitrogen and phosphorus), the sludge also contains heavy metals in varying amounts. An increasingly used method is the incineration of sludge. Thermal processes can be used to convert large amounts of sludge into useful energy. The sewage sludge analyzed for the present paper was extracted from the Wastewater Treatment Station (WWTP) Galati, Romania. The physico-chemical parameters determined were: pH (upH), nutrients and heavy metals. The determination methods were electrochemical, spectrophotometric and energy dispersive X–ray analyses (EDX). The results of the tests made on the content of nutrients in the sewage sludge have shown that existing nutrients can be used to increase the fertility of agricultural soils. The conclusion reached was that these sludge can be safely used on agricultural land and with good agricultural productivity results. To be able to use sewage sludge as a fuel, we need to know its calorific values. For wet sludge, the caloric power is low, while for dry sludge it is high. Higher calorific value and lower calorific value are determined only for dry solids. The apparatus used to determine the calorific power was a Parr 6755 Solution Calorimeter Calorimeter (Parr Instrument Company USA 2010 model). The calorific capacities for the studied sludge indicate that they can be used successfully in incinerators. Mixed with coal, they can also be used to produce electricity. The advantages are: it reduces the cost of obtaining electricity and considerably reduces the amount of sewage sludge.

Keywords: agriculture, incinerators, properties, sewage sludge

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1204 The Performance Improvement of Solar Aided Power Generation System by Introducing the Second Solar Field

Authors: Junjie Wu, Hongjuan Hou, Eric Hu, Yongping Yang

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Solar aided power generation (SAPG) technology has been proven as an efficient way to make use of solar energy for power generation purpose. In an SAPG plant, a solar field consisting of parabolic solar collectors is normally used to supply the solar heat in order to displace the high pressure/temperature extraction steam. To understand the performance of such a SAPG plant, a new simulation model was developed by the authors recently, in which the boiler was treated, as a series of heat exchangers unlike other previous models. Through the simulations using the new model, it was found the outlet properties of reheated steam, e.g. temperature, would decrease due to the introduction of the solar heat. The changes make the (lower stage) turbines work under off-design condition. As a result, the whole plant’s performance may not be optimal. In this paper, the second solar filed was proposed to increase the inlet temperature of steam to be reheated, in order to bring the outlet temperature of reheated steam back to the designed condition. A 600MW SAPG plant was simulated as a case study using the new model to understand the impact of the second solar field on the plant performance. It was found in the study, the 2nd solar field would improve the plant’s performance in terms of cycle efficiency and solar-to-electricity efficiency by 1.91% and 6.01%. The solar-generated electricity produced by per aperture area under the design condition was 187.96W/m2, which was 26.14% higher than the previous design.

Keywords: solar-aided power generation system, off-design performance, coal-saving performance, boiler modelling, integration schemes

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1203 Obesity and Physical Inactivity: Contributing Factors to Hypertension in Early Adults

Authors: Sadaf Ambreen, Ayesha Bibi, Sara Rafiq

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Hypertension is a medical condition in which blood pressure in the arteries is elevated than the normal, having systolic blood pressure more than 120mmHg and diastolic blood pressure more than 80 mmHg. It leads to health complications and increase the risk of diseases such as stroke, heart failure, heart attack, and even death. The aim of the current study was to evaluate nutritional status and activity level among hypertensive early adults in District Mardan Data was collected from the subjects of Public Hospital, Mardan Medical Complex, through questionnaire. A complete information about individual sociodemographic, anthropometry and health status were collected, and physical activity was assessed by using IPAQ questionnaire. A total of 150 individuals were included in the study, in which 90% were females, and 10% were males. Data was analyzed through SPSS Version 22. Majority of the study subjects, 88%, were married, 70% having nuclear living system, 43% were having elementary education, and 43% were working as laborer. Body mass index and waist circumference in female counterpart were found to be positively associated with hypertension and was found statistically significant P=<0.01. Results showed that majority of females were fall in hypertension crisis category with mild activity, and males were having hypertension stage 1 with moderate activity. Our study concluded that non-optimal nutritional status and physical inactivity resulted in elevated blood pressure in females, therefore, lifestyle change such as optimal nutritional status and physical activity may play key role in reducing risk of hypertension.

Keywords: obesity/overwight, body mass index, waist circumference, early adulthood

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1202 Feasibilities for Recovering of Precious Metals from Printed Circuit Board Waste

Authors: Simona Ziukaite, Remigijus Ivanauskas, Gintaras Denafas

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Market development of electrical and electronic equipment and a short life cycle is driven by the increasing waste streams. Gold Au, copper Cu, silver Ag and palladium Pd can be found on printed circuit board. These metals make up the largest value of printed circuit board. Therefore, the printed circuit boards scrap is valuable as potential raw material for precious metals recovery. A comparison of Cu, Au, Ag, Pd recovery from waste printed circuit techniques was selected metals leaching of chemical reagents. The study was conducted using the selected multistage technique for Au, Cu, Ag, Pd recovery of printed circuit board. In the first and second metals leaching stages, as the elution reagent, 2M H2SO4 and H2O2 (35%) was used. In the third stage, leaching of precious metals used solution of 20 g/l of thiourea and 6 g/l of Fe2 (SO4)3. Verify the efficiency of the method was carried out the metals leaching test with aqua regia. Based on the experimental study, the leaching efficiency, using the preferred methodology, 60 % of Au and 85,5 % of Cu dissolution was achieved. Metals leaching efficiency after waste mechanical crushing and thermal treatment have been increased by 1,7 times (40 %) for copper, 1,6 times (37 %) for gold and 1,8 times (44 %) for silver. It was noticed that, the Au amount in old (> 20 years) waste is 17 times more, Cu amount - 4 times more, and Ag - 2 times more than in the new (< 1 years) waste. Palladium in the new printed circuit board waste has not been found, however, it was established that from 1 t of old printed circuit board waste can be recovered 1,064 g of Pd (leaching with aqua regia). It was found that from 1 t of old printed circuit board waste can be recovered 1,064 g of Ag. Precious metals recovery in Lithuania was estimated in this study. Given the amounts of generated printed circuit board waste, the limits for recovery of precious metals were identified.

Keywords: leaching efficiency, limits for recovery, precious metals recovery, printed circuit board waste

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1201 Microwave-Assisted 3D Porous Graphene for Its Multi-Functionalities

Authors: Jung-Hwan Oh, Rajesh Kumar, Il-Kwon Oh

Abstract:

Porous graphene has extensive potential applications in variety of fields such as hydrogen storage, CO oxidation, gas separation, supercapacitors, fuel cells, nanoelectronics, oil adsorption, and so on. However, the generation of some carbon atoms vacancies for precise small holes have been not extensively studied to prevent the agglomerates of graphene sheets and to obtain porous graphene with high surface area. Recently, many research efforts have been presented to develop physical and chemical synthetic approaches for porous graphene. But physical method has very high cost of manufacture and chemical method consumes so many hours for porous graphene. Herein, we propose a porous graphene contained holes with atomic scale precision by embedding metal nano-particles through microwave irradiation for hydrogen storage and CO oxidation multi- functionalities. This proposed synthetic method is appropriate for fast and convenient production of three dimensional nanostructures, which have nanoholes on the graphene surface in consequence of microwave irradiation. The metal nanoparticles are dispersed quickly on the graphene surface and generated uniform nanoholes on the graphene nanosheets. The morphological and structural characterization of the porous graphene were examined by scanning electron microscopy (SEM), transmission scanning electron microscopy (TEM) and RAMAN spectroscopy, respectively. The metal nanoparticle-embedded porous graphene exhibits a microporous volume of 2.586cm3g-1 with an average pore radius of 0.75 nm. HR-TEM analysis was carried out to further characterize the microstructures. By investigating the RAMAN spectra, we can understand the structural changes of graphene. The results of this work demonstrate a possibility to produce a new class of porous graphene. Furthermore, the newly acquired knowledge for the diffusion into graphene can provide useful guidance for the development of the growth of nanostructure.

Keywords: CO oxidation, hydrogen storage, nanocomposites, porous graphene

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1200 Dual Metal Organic Framework Derived N-Doped Fe3C Nanocages Decorated with Ultrathin ZnIn2S4 Nanosheets for Efficient Photocatalytic Hydrogen Generation

Authors: D. Amaranatha Reddy

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Highly efficient and stable co-catalysts materials is of great important for boosting photo charge carrier’s separation, transportation efficiency, and accelerating the catalytic reactive sites of semiconductor photocatalysts. As a result, it is of decisive importance to fabricate low price noble metal free co-catalysts with high catalytic reactivity, but it remains very challenging. Considering this challenge here, dual metal organic frame work derived N-Doped Fe3C nanocages have been rationally designed and decorated with ultrathin ZnIn2S4 nanosheets for efficient photocatalytic hydrogen generation. The fabrication strategy precisely integrates co-catalyst nanocages with ultrathin two-dimensional (2D) semiconductor nanosheets by providing tightly interconnected nano-junctions and helps to suppress the charge carrier’s recombination rate. Furthermore, constructed highly porous hybrid structures expose ample active sites for catalytic reduction reactions and harvest visible light more effectively by light scattering. As a result, fabricated nanostructures exhibit superior solar driven hydrogen evolution rate (9600 µmol/g/h) with an apparent quantum efficiency of 3.6 %, which is relatively higher than the Pt noble metal co-catalyst systems and earlier reported ZnIn2S4 based nanohybrids. We believe that the present work promotes the application of sulfide based nanostructures in solar driven hydrogen production.

Keywords: photocatalysis, water splitting, hydrogen fuel production, solar-driven hydrogen

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1199 Potential of Rice Husk Ash as a Partial Cement Replacement in Concrete for Highways Application

Authors: Ash Ahmed, Fraser Hyndman, Heni Fitriani, John Kamau

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The highway pavement is the biggest structural asset a government can construct and maintain. Concrete rigid pavements are used to carry traffic in large volumes across countries safely and efficiently. Pavement quality concrete mixes have high levels of cement which contribute to up to 10% of global CO₂ emissions. Currently the UK specifies (ground granulated blastfurnace slag) GGBS and (pulverised fuel ash) PFA to reduce the quantity of cement used in pavement construction. GGBS and PFA come from heavy industry that should not be relied upon to improve the sustainability of construction materials. This report shows that cement in pavement quality concrete can be replaced with rice husk ash (RHA) without causing adverse effects to the mechanical properties required for highways. RHA comes from the food production industry and is vital for the growing global population. It is thus a socially responsible objective to use a pozzolan in highway pavement construction that is sourced from an environmentally friendly industry. The report investigates the properties of RHA mixes and compares them to existing pavement quality mixes already used and specified. The report found that sieving RHA and not grinding it gives the best performance. Due to the low density of RHA the investigation found that replacing cement by volume rather than weight provided the best results. Findings showed that CEM II mixed with 20% RHA meets the required specification for pavement quality concrete and mitigates using the comparative CEM I. The investigation also notes that RHA is observed to be more reactive with CEM II rather than CEM I and suits early strength gains required for pavement construction. The report concludes that RHA is a sustainable material that reduces the embodied CO₂ of pavement quality concrete, which is well suited for UK highway specifications and has the potential to improve the lives of people living in the developing countries.

Keywords: pavement, pozzolan, rice husk ash, sustainable concrete

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1198 Regenerative Agriculture Standing at the Intersection of Design, Mycology, and Soil Fertility

Authors: Andrew Gennett

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Designing for fungal development means embracing the symbiotic relationship between the living system and built environment. The potential of mycelium post-colonization is explored for the fabrication of advanced pure mycelium products, going beyond the conventional methods of aggregating materials. Fruiting induction imparts desired material properties such as enhanced environmental resistance. Production approach allows for simultaneous generation of multiple products while scaling up raw materials supply suitable for architectural applications. The following work explores the integration of fungal environmental perception with computational design of built fruiting chambers. Polyporales, are classified by their porous reproductive tissues supported by a wood-like context tissue covered by a hard waterproofing coat of hydrobpobins. Persisting for years in the wild, these species represent material properties that would be highly desired in moving beyond flat sheets of arial mycelium as with leather or bacon applications. Understanding the inherent environmental perception of fungi has become the basis for working with and inducing desired hyphal differentiation. Working within the native signal interpretation of a mycelium mass during fruiting induction provides the means to apply textures and color to the final finishing coat. A delicate interplay between meeting human-centered goals while designing around natural processes of living systems represents a blend of art and science. Architecturally, physical simulations inform model design for simple modular fruiting chambers that change as fungal growth progresses, while biological life science principles describe the internal computations occurring within the fungal hyphae. First, a form filling phase of growth is controlled by growth chamber environment. Second, an initiation phase of growth forms the final exterior finishing texture. Hyphal densification induces cellular cascades, in turn producing the classical hardened cuticle, UV protective molecule production, as well, as waterproofing finish. Upon fruiting process completion, the fully colonized spent substrate holds considerable value and is not considered waste. Instead, it becomes a valuable resource in the next cycle of production scale-up. However, the acquisition of new substrate resources poses a critical question, particularly as these resources become increasingly scarce. Pursuing a regenerative design paradigm from the environmental perspective, the usage of “agricultural waste” for architectural materials would prove a continuation of the destructive practices established by the previous industrial regime. For these residues from fields and forests serve a vital ecological role protecting the soil surface in combating erosion while reducing evaporation and fostering a biologically diverse food web. Instead, urban centers have been identified as abundant sources of new substrate material. Diverting the waste from secondary locations such as food processing centers, papers mills, and recycling facilities not only reduces landfill burden but leverages the latent value of these waste steams as precious resources for mycelium cultivation. In conclusion, working with living systems through innovative built environments for fungal development, provides the needed gain of function and resilience of mycelium products. The next generation of sustainable fungal products will go beyond the current binding process, with a focus upon reducing landfill burden from urban centers. In final considerations, biophilic material builds to an ecologically regenerative recycling production cycle.

Keywords: regenerative agriculture, mycelium fabrication, growth chamber design, sustainable resource acquisition, fungal morphogenesis, soil fertility

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1197 Numerical Simulation of the Dynamic Behavior of a LaNi5 Water Pumping System

Authors: Miled Amel, Ben Maad Hatem, Askri Faouzi, Ben Nasrallah Sassi

Abstract:

Metal hydride water pumping system uses hydrogen as working fluid to pump water for low head and high discharge. The principal operation of this pump is based on the desorption of hydrogen at high pressure and its absorption at low pressure by a metal hydride. This work is devoted to study a concept of the dynamic behavior of a metal hydride pump using unsteady model and LaNi5 as hydriding alloy. This study shows that with MHP, it is possible to pump 340l/kg-cycle of water in 15 000s using 1 Kg of LaNi5 at a desorption temperature of 360 K, a pumping head equal to 5 m and a desorption gear ratio equal to 33. This study reveals also that the error given by the steady model, using LaNi5 is about 2%.A dimensional mathematical model and the governing equations of the pump were presented to predict the coupled heat and mass transfer within the MHP. Then, a numerical simulation is carried out to present the time evolution of the specific water discharge and to test the effect of different parameters (desorption temperature, absorption temperature, desorption gear ratio) on the performance of the water pumping system (specific water discharge, pumping efficiency and pumping time). In addition, a comparison between results obtained with steady and unsteady model is performed with different hydride mass. Finally, a geometric configuration of the reactor is simulated to optimize the pumping time.

Keywords: dynamic behavior, LaNi5, performance of water pumping system, unsteady model

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1196 Creativity as a National System: An Exploratory Model towards Enhance Innovation Ecosystems

Authors: Oscar Javier Montiel Mendez

Abstract:

The link between knowledge-creativity-innovation-entrepreneurship is well established, and broadly emphasized the importance of national innovation systems (NIS) as an approach stresses that the flow of information and technology among people, organizations and institutions are key to its process. Understanding the linkages among the actors involved in innovation is relevant to NIS. Creativity is supposed to fuel NIS, mainly focusing on a personal, group or organizational level, leaving aside the fourth one, as a national system. It is suggested that NIS takes Creativity for granted, an ex-ante stage already solved through some mechanisms, like programs for nurturing it at elementary and secondary schools, universities, or public/organizational specific programs. Or worse, that the individual already has this competence, and that the elements of the NIS will communicate between in a way that will lead to the creation of S curves, with an impact on national systems/programs on entrepreneurship, clusters, and the economy. But creativity constantly appears at any time during NIS, being the key input. Under an initial, exploratory, focused and refined literature review, based on Csikszentmihalyi’s systemic model, Amabile's componential theory, Kaufman and Beghetto’s 4C model, and the OECD’s (Organisation for Economic Co-operation and Development) NIS model (expanded), an NCS theoretical model is elaborated. Its suggested that its implementation could become a significant factor helping strengthen local, regional and national economies. The results also suggest that the establishment of a national creativity system (NCS), something that appears not been previously addressed, as a strategic/vital companion for a NIS, installing it not only as a national education strategy, but as its foundation, managing it and measuring its impact on NIS, entrepreneurship and the rest of the ecosystem, could make more effective public policies. Likewise, it should have a beneficial impact on the efforts of all the stakeholders involved and should help prevent some of the possible failures that NIS present.

Keywords: national creativity system, national innovation system, entrepreneurship ecosystem, systemic creativity

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1195 Hardware-In-The-Loop Relative Motion Control: Theory, Simulation and Experimentation

Authors: O. B. Iskender, K. V. Ling, V. Dubanchet, L. Simonini

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This paper presents a Guidance and Control (G&C) strategy to address spacecraft maneuvering problem for future Rendezvous and Docking (RVD) missions. The proposed strategy allows safe and propellant efficient trajectories for space servicing missions including tasks such as approaching, inspecting and capturing. This work provides the validation test results of the G&C laws using a Hardware-In-the-Loop (HIL) setup with two robotic mockups representing the chaser and the target spacecraft. Through this paper, the challenges of the relative motion control in space are first summarized, and in particular, the constraints imposed by the mission, spacecraft and, onboard processing capabilities. Second, the proposed algorithm is introduced by presenting the formulation of constrained Model Predictive Control (MPC) to optimize the fuel consumption and explicitly handle the physical and geometric constraints in the system, e.g. thruster or Line-Of-Sight (LOS) constraints. Additionally, the coupling between translational motion and rotational motion is addressed via dual quaternion based kinematic description and accordingly explained. The resulting convex optimization problem allows real-time implementation capability based on a detailed discussion on the computational time requirements and the obtained results with respect to the onboard computer and future trends of space processors capabilities. Finally, the performance of the algorithm is presented in the scope of a potential future mission and of the available equipment. The results also cover a comparison between the proposed algorithms with Linear–quadratic regulator (LQR) based control law to highlight the clear advantages of the MPC formulation.

Keywords: autonomous vehicles, embedded optimization, real-time experiment, rendezvous and docking, space robotics

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1194 The Proton Flow Battery for Storing Renewable Energy: A Theoretical Model of Electrochemical Hydrogen Storage in an Activated Carbon Electrode

Authors: Sh. Heidari, A. J. Andrews, A. Oberoi

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Electrochemical storage of hydrogen in activated carbon electrodes as part of a reversible fuel cell offers a potentially attractive option for storing surplus electrical energy from inherently variable solar and wind energy resources. Such a system – which we have called a proton flow battery – promises to have a roundtrip energy efficiency comparable to lithium ion batteries, while having higher gravimetric and volumetric energy densities. In this paper, a theoretical model is presented of the process of H+ ion (proton) conduction through an acid electrolyte into a highly porous activated carbon electrode where it is neutralised and absorbed on the inner surfaces of pores. A Butler-Volmer type equation relates the rate of adsorption to the potential difference between the activated carbon surface and the electrolyte. This model for the hydrogen storage electrode is then incorporated into a more general computer model based on MATLAB software of the entire electrochemical cell including the oxygen electrode. Hence a theoretical voltage-current curve is generated for given input parameters for a particular activated carbon electrode. It is shown that theoretical VI curves produced by the model can be fitted accurately to experimental data from an actual electrochemical cell with the same characteristics. By obtaining the best-fit values of input parameters, such as the exchange current density and charge transfer coefficient for the hydrogen adsorption reaction, an improved understanding of the adsorption reaction is obtained. This new model will assist in designing improved proton flow batteries for storing solar and wind energy.

Keywords: electrochemical hydrogen storage, proton flow battery, butler-volmer equation, activated carbon

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1193 Synthesis and Anticancer Evaluation of Substituted 2-(3,4-Dimethoxyphenyl) Benzazoles

Authors: Cigdem Karaaslan, Yalcin Duydu, Aylin Ustundag, Can Ozgur Yalcın, Hakan Goker

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Benzazole nucleus is found in the structure of many compounds as anticancer agents. Bendamustine (Alkylating agent), Nocodazole (Mitotic inhibitor), Veliparib (PARP inhibitor), Glasdegib (SMO inhibitor) are clinically used as anticancer therapeutics which bearing benzimidazole moiety. Based on the principle of bioisosterism in the present work, 23 compounds belonging to 2-(3,4-dimethoxy-phenyl) benzazoles and imidazopyridine series were synthesized and evaluated for their anticancer activities. N-(5-Chloro-2-hydroxyphenyl)-3,4-dimethoxybenzamide, was obtained by the amidation of 2-hydroxy-5-chloroaniline with 3,4-dimethoxybenzoic acid by using 1,1'-carbonyldiimidazole. Cyclization of benzamide derivative to benzoxazole, was achieved by p-toluenesulfonic acid. Other 1H-benz (or pyrido) azoles were prepared by the reaction between 2-aminothiophenol, o-phenylenediamine, o-pyridinediamine with sodium metabisulfite adduct of 3,4-dimethoxybenzaldehyde. The NMR assignments of the dimethoxy groups were established by the Nuclear Overhauser Effect Spectroscopy. A compound named, 5(4),7(6)-Dichloro-2-(3,4-dimethoxy) phenyl-1H-benzimidazole, bearing two chlorine atoms at the 5(4) and 7(6) positions of the benzene moiety of benzimidazole was found the most potent analogue, against A549 cells with the GI50 value of 1.5 µg/mL. In addition, 2-(3,4-Dimethoxyphenyl)-5,6-dimethyl-1H-benzimi-dazole showed remarkable cell growth inhibition against MCF-7 and HeLa cells with the GI₅₀ values of 7 and 5.5 µg/mL, respectively. It could be concluded that introduction of di-chloro atoms at the phenyl ring of 2-(3,4-dimethoxyphenyl)-1H-benzimidazoles increase significant cytotoxicity to selected human tumor cell lines in comparison to other all benzazoles synthesized in this study. Unsubstituted 2-(3,4-dimethoxyphenyl) imidazopyridines also gave the good inhibitory profile against A549 and HeLa cells.

Keywords: 3, 4-Dimethoxyphenyl, 1H-benzimidazole, benzazole, imidazopyridine

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1192 World Peace and Conflict Resolution: A Solution from a Buddhist Point of View

Authors: Samitharathana R. Wadigala

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The peace will not be established until the self-consciousness would reveal in the human beings. In this nuclear age, the establishment of a lasting peace on the earth represents the primary condition for the preservation of human civilization and survival of human beings. Nothing perhaps is so important and indispensable as the achievement and maintenance of peace in the modern world today. Peace in today’s world implies much more than the mere absence of war and violence. In the interdependent world of today the United Nations needs to be representative of the modern world and democratic in its functioning because it came into existence to save the generations from the scourge of war and conflict. Buddhism is the religion of peaceful co-existence and philosophy of enlightenment. Violence and conflict from the perspective of the Buddhist theory of interdependent origination (Paṭiccasamuppāda) are same with everything else in the world a product of causes and conditions. Buddhism is totally compatible with the congenial and peaceful global order. The canonical literature, doctrines, and philosophy of Buddhism are the best suited for inter-faith dialogue, harmony, and universal peace. Even today Buddhism can resurrect the universal brotherhood, peaceful co-existence and harmonious surroundings in the comity of nations. With its increasing vitality in regions around the world, many people today turn to Buddhism for relief and guidance at the time when peace seems to be a deferred dream more than ever. From a Buddhist point of view the roots of all unwholesome actions (Conflict) i. e. greed, hatred and delusion are viewed as the root cause of all human conflicts. Conflict often emanates from attachment to material things: pleasures, property, territory, wealth, economic dominance or political superiority. Buddhism has some particularly rich resources for deployment in dissolving conflict. Buddhism addresses the Buddhist perspective on the causes of conflict and ways to resolve conflict to realize world peace. The world has enough to satisfy every body’s needs but not every body’s greed.

Keywords: Buddhism, conflict-violence, peace, self-consciousness

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1191 Hydrogeochemistry Preliminary Study of Groundwater Conservation in Buton Island, Southeast Sulawesi, Indonesia

Authors: M. S. M. Prahastomi, Riki Sunaryo, Lorasa Ximanes

Abstract:

The research takes place in EP Area, in the Northern part of Buton, Southeast Sulawesi Province, Indonesia. It is one example of karst areas that have good water resources potential. The landscape is in the form of valleys and hills which is good enough for recharge zone and discharge zones of groundwater. However, the geological characteristics of karst dissolution and a complex geological structure are quite influential to the groundwater flow system in the region. The Discharge of groundwater to the surface can be caused by a fracture in the rock, Underground River due to dissolution, and the contact between permeable rocks with impermeable rocks. In the concept of hydrogeology, groundwater is one of the components of the hydrological cycle which is closely linked to the availability of water under the surface, precipitation, infiltration, percolation, evapotranspiration, and surface runoff. Conceptually, the condition of recharge and discharge areas can be identified through a research distribution springs in a region. The understanding of the condition and the nature of the potential catchment area of groundwater flow, mainly from the catchment area to the discharge area, is urgently needed. This research aimed to assess the general geological conditions of the study area, which is expected to provide an overview of groundwater flow events that used by the public as well as industry. Behavioral characteristics of groundwater become an integral part in the search for potential groundwater in the study area. As for the research methods used hydrogeology mapping and laboratory works.

Keywords: Buton Island, groundwater conservation, hydrogeochemistry preliminary, karst

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1190 An Exploratory Case Study of the Interference of Erotic Transference in the Longevity of Psychoanalytic Treatment

Authors: Mehravar Javid, Rohma Hassan, J. DeSilva

Abstract:

In this exploratory case study, a 37-year-old male patient who previously terminated treatment after four months of therapy with a different therapist begins anew with a 38-year-old female therapist and undergoes a similar cycle of premature termination, with added discourse caused by erotic transference. Process notes and records of the therapy treatment indicate that during the short course of treatment, the patient explored his difficulties navigating personal relationships, both current and past, and his difficulties coping with hypochondriasis. The therapist becomes tasked with not only navigating the patient’s inner conflict but also how she relates to the patient in the countertransference process while maintaining professional boundaries. This includes empathizing with the patient while also experiencing discomfort in the erotic transference from a professional standpoint. When the patient terminates once more, the therapist reflects on the possible reasons for termination. This includes the patient’s difficulties with tolerating interpretations, which cause him to blame himself for past events. These interpretations were also very frequent, contributing to the emotional burden the patient experienced. The therapist reflected on the use of interpretation versus exploration of the patient’s feelings and how exploring his feelings, including his feelings towards her, would have allowed for an opportunity to explore the emotions that troubled him more deeply. This includes exploring the patient’s anger and fear, which stem from unresolved conflicts from his childhood. Moreover, the erotic transference served as an enactment of previous experiences in which the patient feared losing what he loved, leading him to opt for premature termination instead of losing his ability to control the relationship and experience loss.

Keywords: countertransference, erotic transference, premature termination, therapist-client boundaries, transference

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1189 Experimental Study of Al₂O₃ and SiC Nano Particles on Tensile Strength of Al 1100 Sheet Produced by Accumulative Press Bonding Process

Authors: M. Zadshakoyan, H. Marassem Bonab, P. M. Keshtiban

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The SPD process widely used to optimize microstructure, strength and mechanical properties of the metals. Processes such as ARB and APB could have a considerable impact on improving the properties of metals. The aluminum material after steel, known as the most used metal, Because of its low strength, there are restrictions on the use of this metal, it is required to spread further studies to increase strength and improve the mechanical properties of this light weight metal. In this study, Annealed aluminum material, with yield strength of 85 MPa and tensile strength of 124 MPa, sliced into 2 sheets with dimensions of 30 and 25 mm and the thickness of 1.5 mm. then the sheets press bonded under 6 cycles, which increased the ultimate strength to 281 MPa. In addition, by adding 0.1%Wt of SiC particles to interface of the sheets, the sheets press bonded by 6 cycles to achieve a homogeneous composite. The same operation using Al2O3 particles and a mixture of SiC+Al2O3 particles was repeated and the amount of strength and elongation of produced composites compared with each other and with pure 6 cycle press bonded Aluminum. The results indicated that the ultimate strength of Al/SiC composite was 2.6 times greater than Annealed aluminum. And Al/Al2O3 and Al/Al2O3+SiC samples were low strength than Al/SiC sample. The pure 6 time press bonded Aluminum had lowest strength by 2.2 times greater than annealed aluminum. Strength of aluminum was increased by making the metal matrix composite. Also, it was found that the hardness of pure Aluminum increased 1.7 times after 6 cycles of APB process, hardness of the composite samples improved further, so that, the hardness of Al/SiC increased up to 2.51 times greater than annealed aluminum.

Keywords: APB, nano composite, nano particles, severe plastic deformation

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1188 Rice Serine/Threonine Kinase 1 Is Required for the Stimulation of OsNug2 GTPase Activity

Authors: Jae Bok Heo, Yun Mi Lee, Hee Rang Yun

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Several GTPases are required for ribosome biogenesis and assembly. We recently characterized rice (Oryza sativa) nuclear/nucleolar GTPase 2 (OsNug2), belonging to the YlqF/YawG family of GTPases, as playing a role in pre-60S ribosomal subunit maturation. To investigate the potential factors involved in regulating the function of OsNug2, yeast two-hybrid screens were carried out using OsNug2 as bait. Rice serine/threonine kinase 1 (OsSTK1) was identified as a potential interacting protein candidate. In vitro pull down and bimolecular fluorescence complementation assays confirmed the interaction between OsNug2 and OsSTK1, and like green fluorescent protein-tagged OsNug2, green fluorescent protein-tagged OsSTK1 was targeted to the nucleus of Arabidopsis protoplasts. OsSTK1 was not found to affect the GTP-binding activity of OsNug2; however, when recombinant OsSTK1 was included in OsNug2 assay reaction mixtures, OsSTK1 increased the GTPase activity of OsNug2. To test whether OsSTK1 phosphorylates OsNug2 in vitro, a kinase assay was performed. OsSTK1 was found to have weak autophosphorylation activity and strongly phosphorylated serine 209 of OsNug2. Yeast complementation testing resulted in a GAL::OsNug2(S209N) mutant-harboring yeast strain exhibiting a growth-defective phenotype on galactose medium at 39°C, divergent from that of a yeast strain harboring GAL::OsNug2. The intrinsic GTPase activity of mutant OsNug2(S209N) was found to be similar to that of OsNug2, was not fully enhanced upon weak binding of OsSTK1. Our findings reported here indicate that OsSTK1 functions as a positive regulator protein of OsNug2 by enhancing the GTPase activity of OsNug2, and that the phosphorylation of serine 209 of OsNug2 is essential for the complete function of OsNug2 in ribosome biogenesis.

Keywords: OsSTK1, OsNug2, GTPase activity, GTP binding activity, phosphorylation

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1187 Numerical Simulation of the Flowing of Ice Slurry in Seawater Pipe of Polar Ships

Authors: Li Xu, Huanbao Jiang, Zhenfei Huang, Lailai Zhang

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In recent years, as global warming, the sea-ice extent of North Arctic undergoes an evident decrease and Arctic channel has attracted the attention of shipping industry. Ice crystals existing in the seawater of Arctic channel which enter the seawater system of the ship with the seawater were found blocking the seawater pipe. The appearance of cooler paralysis, auxiliary machine error and even ship power system paralysis may be happened if seriously. In order to reduce the effect of high temperature in auxiliary equipment, seawater system will use external ice-water to participate in the cooling cycle and achieve the state of its flow. The distribution of ice crystals in seawater pipe can be achieved. As the ice slurry system is solid liquid two-phase system, the flow process of ice-water mixture is very complex and diverse. In this paper, the flow process in seawater pipe of ice slurry is simulated with fluid dynamics simulation software based on k-ε turbulence model. As the ice packing fraction is a key factor effecting the distribution of ice crystals, the influence of ice packing fraction on the flowing process of ice slurry is analyzed. In this work, the simulation results show that as the ice packing fraction is relatively large, the distribution of ice crystals is uneven in the flowing process of the seawater which has such disadvantage as increase the possibility of blocking, that will provide scientific forecasting methods for the forming of ice block in seawater piping system. It has important significance for the reliability of the operating of polar ships in the future.

Keywords: ice slurry, seawater pipe, ice packing fraction, numerical simulation

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1186 Modeling and Temperature Control of Water-cooled PEMFC System Using Intelligent Algorithm

Authors: Chen Jun-Hong, He Pu, Tao Wen-Quan

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Proton exchange membrane fuel cell (PEMFC) is the most promising future energy source owing to its low operating temperature, high energy efficiency, high power density, and environmental friendliness. In this paper, a comprehensive PEMFC system control-oriented model is developed in the Matlab/Simulink environment, which includes the hydrogen supply subsystem, air supply subsystem, and thermal management subsystem. Besides, Improved Artificial Bee Colony (IABC) is used in the parameter identification of PEMFC semi-empirical equations, making the maximum relative error between simulation data and the experimental data less than 0.4%. Operation temperature is essential for PEMFC, both high and low temperatures are disadvantageous. In the thermal management subsystem, water pump and fan are both controlled with the PID controller to maintain the appreciate operation temperature of PEMFC for the requirements of safe and efficient operation. To improve the control effect further, fuzzy control is introduced to optimize the PID controller of the pump, and the Radial Basis Function (RBF) neural network is introduced to optimize the PID controller of the fan. The results demonstrate that Fuzzy-PID and RBF-PID can achieve a better control effect with 22.66% decrease in Integral Absolute Error Criterion (IAE) of T_st (Temperature of PEMFC) and 77.56% decrease in IAE of T_in (Temperature of inlet cooling water) compared with traditional PID. In the end, a novel thermal management structure is proposed, which uses the cooling air passing through the main radiator to continue cooling the secondary radiator. In this thermal management structure, the parasitic power dissipation can be reduced by 69.94%, and the control effect can be improved with a 52.88% decrease in IAE of T_in under the same controller.

Keywords: PEMFC system, parameter identification, temperature control, Fuzzy-PID, RBF-PID, parasitic power

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