Search results for: rate of bio gas production
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 14356

Search results for: rate of bio gas production

10456 A Cross-Disciplinary Educational Model in Biomanufacturing to Sustain a Competitive Workforce Ecosystem

Authors: Rosa Buxeda, Lorenzo Saliceti-Piazza, Rodolfo J. Romañach, Luis Ríos, Sandra L. Maldonado-Ramírez

Abstract:

Biopharmaceuticals manufacturing is one of the major economic activities worldwide. Ninety-three percent of the workforce in a biomanufacturing environment concentrates in production-related areas. As a result, strategic collaborations between industry and academia are crucial to ensure the availability of knowledgeable workforce needed in an economic region to become competitive in biomanufacturing. In the past decade, our institution has been a key strategic partner with multinational biotechnology companies in supplying science and engineering graduates in the field of industrial biotechnology. Initiatives addressing all levels of the educational pipeline, from K-12 to college to continued education for company employees have been established along a ten-year span. The Amgen BioTalents Program was designed to provide undergraduate science and engineering students with training in biomanufacturing. The areas targeted by this educational program enhance their academic development, since these topics are not part of their traditional science and engineering curricula. The educational curriculum involved the process of producing a biomolecule from the genetic engineering of cells to the production of an especially targeted polypeptide, protein expression and purification, to quality control, and validation. This paper will report and describe the implementation details and outcomes of the first sessions of the program.

Keywords: biomanufacturing curriculum, interdisciplinary learning, workforce development, industry-academia partnering

Procedia PDF Downloads 281
10455 Ultrasonic Techniques to Characterize and Monitor Water-in-Oil Emulsion

Authors: E. A. Alshaafi, A. Prakash

Abstract:

Oil-water emulsions are commonly encountered in various industrial operations and at different stages of crude oil production and processing. Emulsions are often difficult to track and treat and can cause a number of costly problems which need to be avoided. The characteristics of the emulsion phase can vary with crude composition and types of impurities present in oil. The objectives of this study are the development of ultrasonic techniques to track and characterize emulsion phase generated during production and cleaning of crude oil. The position of emulsion layer is monitored with the help of ultrasonic probes suitably placed in the vessel. The sensitivity of the technique and its potential has been demonstrated based on extensive testing with different oil samples. The technique is also being developed to monitor emulsion phase characteristics such as stability, composition, and droplet size distribution. The ultrasonic parameters recorded are changes in acoustic velocity, signal attenuation and its frequency spectrum. Emulsion has been prepared with light mineral oil sample and the effects of various factors including mixing speed, temperature, surfactant, and solid particles concentrations have been investigated. The applied frequency for ultrasonic waves has been varied from 1 to 5 MHz to carry out a sensitivity analysis. Emulsion droplet structure is observed with optical microscopy and stability is examined by tracking the changes in ultrasonic parameters with time. A model based on ultrasonic attenuation spectroscopy is being developed and tested to track changes in droplet size distribution with time.

Keywords: ultrasonic techniques, emulsion, characterization, droplet size

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10454 Microplastic Accumulation in Native and Invasive Sea Urchin Populations on Lipsi Island (Aegean Sea)

Authors: Ella Zahra

Abstract:

Sea urchins are keystone species in many global benthic ecosystems. The concentration of microplastics (MPs) in sea urchin organs was quantified in 120 individuals of 2 different species and from 4 sites across the Greek island Lipsi, with special interest in the differences between the native Arbacia lixula and the invasive Diadema setosum. Over 93% of MPs observed in both species were fibrous. MP abundance was found to correlate with exposure to open sea and harsh prevailing winds, irrespective of proximity to urban activities. The MP abundance in the invasive species was not found to be significantly dependent on site. Interestingly, the smaller native species contained significantly larger sized MPs than the invasive, possibly as a result of a greater feeding rate in A. lixula individuals. Sexually immature urchins may also have a higher feeding rate, giving rise to the negative correlation between gonad index and MPs per individual. The size of MPs ranged from 10µm to 24210µm, heavily skewed towards smaller particles. Few differences in colour were noted between the species and sites. MPs were detected in 100% of the samples with abundance ranging from 19.27 ± 6.77 to 26.83 ± 8.15 items per individual, or 3.55 ± 3.73 to 7.34 ± 10.51 items per gram of wet organ weight. This high value could lead to health risks in East Asia and the Mediterranean, where sea urchin is widely consumed, due to toxins adsorbed to the MPs.

Keywords: microplastics, plastic pollution, invertebrate ecology, invasive marine species

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10453 Utilization of Whey for the Production of β-Galactosidase Using Yeast and Fungal Culture

Authors: Rupinder Kaur, Parmjit S. Panesar, Ram S. Singh

Abstract:

Whey is the lactose rich by-product of the dairy industry, having good amount of nutrient reservoir. Most abundant nutrients are lactose, soluble proteins, lipids and mineral salts. Disposing of whey by most of milk plants which do not have proper pre-treatment system is the major issue. As a result of which, there can be significant loss of potential food and energy source. Thus, whey has been explored as the substrate for the synthesis of different value added products such as enzymes. β-galactosidase is one of the important enzymes and has become the major focus of research due to its ability to catalyze both hydrolytic as well as transgalactosylation reaction simultaneously. The enzyme is widely used in dairy industry as it catalyzes the transformation of lactose to glucose and galactose, making it suitable for the lactose intolerant people. The enzyme is intracellular in both bacteria and yeast, whereas for molds, it has an extracellular location. The present work was carried to utilize the whey for the production of β-galactosidase enzyme using both yeast and fungal cultures. The yeast isolate Kluyveromyces marxianus WIG2 and various fungal strains have been used in the present study. Different disruption techniques have also been investigated for the extraction of the enzyme produced intracellularly from yeast cells. Among the different methods tested for the disruption of yeast cells, SDS-chloroform showed the maximum β-galactosidase activity. In case of the tested fungal cultures, Aureobasidium pullulans NCIM 1050, was observed to be the maximum extracellular enzyme producer.

Keywords: β-galactosidase, fungus, yeast, whey

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10452 Efficiency of Lavandula angustifolia Mill and Zataria multiflora Boiss essential oils on nutritional indices of Tribolium confusum Jacquelin du Val (Col.: Tenebrionidae)

Authors: Karim Saeidi

Abstract:

One of the most important pests in the warehouses is the flour beetle, Tribolium confusum Jacquelin du Val (Col.: Tenebrionidae). Regarding the high degree of damage of stored product pests and dangerous effects of the chemical control using plant extracts and their components are some of the best approaches to control these pests. Antifeedant activity of plant extracts from Lavandula angustifolia Mill and Zataria multiflora Boiss using hydro-distillation were tested against the flour beetle, Tribolium confusum Jacquelin du Val. The nutritional indices: relative growth rate (RGR), relative consumption rate (RCR), the efficiency of conversion of ingested food (ECI), and feeding deterrence index (FDI) were measured for adult insects. Treatments were evaluated using a flour disk bioassay in the dark; at 25±1ᵒC and 60±5% R. H. Concentrations of 0, 0.1, 0.5, 0.75, 1, 1.5, and 2 μl/disk were prepared from each essential oil. After 72 h, nutritional indices were calculated. L. angustifolia oils were more effective than Z. multiflora oils by significantly decreasing the RGR, RCR, and ECI. Feeding deterrence index (FDI) of L. angustifolia essential oil was increased significantly as essential oil concentration increased. The essential oil of L. angustifolia was more effective on FDI than Z. multiflora in some concentration.

Keywords: essential oil, nutritional indices, Tribolium confusum

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10451 Influence of the Moisture Content on the Flowability of Fine-Grained Iron Ore Concentrate

Authors: C. Lanzerstorfer, M. Hinterberger

Abstract:

The iron content of the ore used is crucial for the productivity and coke consumption rate in blast furnace pig iron production. Therefore, most iron ore deposits are processed in beneficiation plants to increase the iron content and remove impurities. In several comminution stages, the particle size of the ore is reduced to ensure that the iron oxides are physically liberated from the gangue. Subsequently, physical separation processes are applied to concentrate the iron ore. The fine-grained ore concentrates produced need to be transported, stored, and processed. For smooth operation of these processes, the flow properties of the material are crucial. The flowability of powders depends on several properties of the material: grain size, grain size distribution, grain shape, and moisture content of the material. The flowability of powders can be measured using ring shear testers. In this study, the influence of the moisture content on the flowability for the Krivoy Rog magnetite iron ore concentrate was investigated. Dry iron ore concentrate was mixed with varying amounts of water to produce samples with a moisture content in the range of 0.2 to 12.2%. The flowability of the samples was investigated using a Schulze ring shear tester. At all measured values of the normal stress (1.0 kPa – 20 kPa), the flowability decreased significantly from dry ore to a moisture content of approximately 3-5%. At higher moisture contents, the flowability was nearly constant, while at the maximum moisture content the flowability improved for high values of the normal stress only. The results also showed an improving flowability with increasing consolidation stress for all moisture content levels investigated. The wall friction angle of the dust with carbon steel (S235JR), and an ultra-high molecule low-pressure polyethylene (Robalon) was also investigated. The wall friction angle increased significantly from dry ore to a moisture content of approximately 3%. For higher moisture content levels, the wall friction angles were nearly constant. Generally, the wall friction angle was approximately 4° lower at the higher wall normal stress.

Keywords: iron ore concentrate, flowability, moisture content, wall friction angle

Procedia PDF Downloads 315
10450 An Analysis of Economical Drivers and Technical Challenges for Large-Scale Biohydrogen Deployment

Authors: Rouzbeh Jafari, Joe Nava

Abstract:

This study includes learnings from an engineering practice normally performed on large scale biohydrogen processes. If properly scale-up is done, biohydrogen can be a reliable pathway for biowaste valorization. Most of the studies on biohydrogen process development have used model feedstock to investigate process key performance indicators (KPIs). This study does not intend to compare different technologies with model feedstock. However, it reports economic drivers and technical challenges which help in developing a road map for expanding biohydrogen economy deployment in Canada. BBA is a consulting firm responsible for the design of hydrogen production projects. Through executing these projects, activity has been performed to identify, register and mitigate technical drawbacks of large-scale hydrogen production. Those learnings, in this study, have been applied to the biohydrogen process. Through data collected by a comprehensive literature review, a base case has been considered as a reference, and several case studies have been performed. Critical parameters of the process were identified and through common engineering practice (process design, simulation, cost estimate, and life cycle assessment) impact of these parameters on the commercialization risk matrix and class 5 cost estimations were reported. The process considered in this study is food waste and woody biomass dark fermentation. To propose a reliable road map to develop a sustainable biohydrogen production process impact of critical parameters was studied on the end-to-end process. These parameters were 1) feedstock composition, 2) feedstock pre-treatment, 3) unit operation selection, and 4) multi-product concept. A couple of emerging technologies also were assessed such as photo-fermentation, integrated dark fermentation, and using ultrasound and microwave to break-down feedstock`s complex matrix and increase overall hydrogen yield. To properly report the impact of each parameter KPIs were identified as 1) Hydrogen yield, 2) energy consumption, 3) secondary waste generated, 4) CO2 footprint, 5) Product profile, 6) $/kg-H2 and 5) environmental impact. The feedstock is the main parameter defining the economic viability of biohydrogen production. Through parametric studies, it was found that biohydrogen production favors feedstock with higher carbohydrates. The feedstock composition was varied, by increasing one critical element (such as carbohydrate) and monitoring KPIs evolution. Different cases were studied with diverse feedstock, such as energy crops, wastewater slug, and lignocellulosic waste. The base case process was applied to have reference KPIs values and modifications such as pretreatment and feedstock mix-and-match were implemented to investigate KPIs changes. The complexity of the feedstock is the main bottleneck in the successful commercial deployment of the biohydrogen process as a reliable pathway for waste valorization. Hydrogen yield, reaction kinetics, and performance of key unit operations highly impacted as feedstock composition fluctuates during the lifetime of the process or from one case to another. In this case, concept of multi-product becomes more reliable. In this concept, the process is not designed to produce only one target product such as biohydrogen but will have two or multiple products (biohydrogen and biomethane or biochemicals). This new approach is being investigated by the BBA team and the results will be shared in another scientific contribution.

Keywords: biohydrogen, process scale-up, economic evaluation, commercialization uncertainties, hydrogen economy

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10449 Dynamic Effects of Energy Consumption, Economic Growth, International Trade and Urbanization on Environmental Degradation in Nigeria

Authors: Abdulkarim Yusuf

Abstract:

Motivation: A crucial but difficult goal for governments and policymakers in Nigeria in recent years has been the sustainability of economic growth. This goal must be accomplished by regulating or lowering greenhouse gas emissions, which calls for switching to a low- or zero-carbon production system. The lack of in-depth empirical studies on the environmental impact of socioeconomic variables on Nigeria and a number of unresolved issues from earlier research is what led to the current study. Objective: This study fills an important empirical gap by investigating the existence of an Environmental Kuznets Curve hypothesis and the long and short-run dynamic impact of socioeconomic variables on ecological sustainability in Nigeria. Data and method: Annual time series data covering the period 1980 to 2020 and the Autoregressive Distributed Lag technique in the presence of structural breaks were adopted for this study. Results: The empirical findings support the existence of the environmental Kuznets curve hypothesis for Nigeria in the long and short run. Energy consumption and total import exacerbate environmental deterioration in the long and short run, whereas total export improves environmental quality in the long and short run. Financial development, which contributed to a conspicuous decrease in the level of environmental destruction in the long run, escalated it in the short run. In contrast, urbanization caused a significant increase in environmental damage in the long run but motivated a decrease in biodiversity loss in the short run. Implications: The government, policymakers, and all energy stakeholders should take additional measures to ensure the implementation and diversification of energy sources to accommodate more renewable energy sources that emit less carbon in order to promote efficiency in Nigeria's production processes and lower carbon emissions. In order to promote the production and trade of environmentally friendly goods, they should also revise and strengthen environmental policies. With affordable, dependable, and sustainable energy use for higher productivity and inclusive growth, Nigeria will be able to achieve its long-term development goals of good health and wellbeing.

Keywords: economic growth, energy consumption, environmental degradation, environmental Kuznets curve, urbanization, Nigeria

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10448 Waste Burial to the Pressure Deficit Areas in the Eastern Siberia

Authors: L. Abukova, O. Abramova, A. Goreva, Y. Yakovlev

Abstract:

Important executive decisions on oil and gas production stimulation in Eastern Siberia have been recently taken. There are unique and large fields of oil, gas, and gas-condensate in Eastern Siberia. The Talakan, Koyumbinskoye, Yurubcheno-Tahomskoye, Kovykta, Chayadinskoye fields are supposed to be developed first. It will result in an abrupt increase in environmental load on the nature of Eastern Siberia. In Eastern Siberia, the introduction of ecological imperatives in hydrocarbon production is still realistic. Underground water movement is the one of the most important factors of the ecosystems condition management. Oil and gas production is associated with the forced displacement of huge water masses, mixing waters of different composition, and origin that determines the extent of anthropogenic impact on water drive systems and their protective reaction. An extensive hydrogeological system of the depression type is identified in the pre-salt deposits here. Pressure relieve here is steady up to the basement. The decrease of the hydrodynamic potential towards the basement with such a gradient resulted in reformation of the fields in process of historical (geological) development of the Nepsko-Botuobinskaya anteclise. The depression hydrodynamic systems are characterized by extremely high isolation and can only exist under such closed conditions. A steady nature of water movement due to a strictly negative gradient of reservoir pressure makes it quite possible to use environmentally-harmful liquid substances instead of water. Disposal of the most hazardous wastes is the most expedient in the deposits of the crystalline basement in certain structures distant from oil and gas fields. The time period for storage of environmentally-harmful liquid substances may be calculated by means of the geological time scales ensuring their complete prevention from releasing into environment or air even during strong earthquakes. Disposal of wastes of chemical and nuclear industries is a matter of special consideration. The existing methods of storage and disposal of wastes are very expensive. The methods applied at the moment for storage of nuclear wastes at the depth of several meters, even in the most durable containers, constitute a potential danger. The enormous size of the depression system of the Nepsko-Botuobinskaya anteclise makes it possible to easily identify such objects at the depth below 1500 m where nuclear wastes will be stored indefinitely without any environmental impact. Thus, the water drive system of the Nepsko-Botuobinskaya anteclise is the ideal object for large-volume injection of environmentally harmful liquid substances even if there are large oil and gas accumulations in the subsurface. Specific geological and hydrodynamic conditions of the system allow the production of hydrocarbons from the subsurface simultaneously with the disposal of industrial wastes of oil and gas, mining, chemical, and nuclear industries without any environmental impact.

Keywords: Eastern Siberia, formation pressure, underground water, waste burial

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10447 Modelling of Solidification in a Latent Thermal Energy Storage with a Finned Tube Bundle Heat Exchanger Unit

Authors: Remo Waser, Simon Maranda, Anastasia Stamatiou, Ludger J. Fischer, Joerg Worlitschek

Abstract:

In latent heat storage, a phase change material (PCM) is used to store thermal energy. The heat transfer rate during solidification is limited and considered as a key challenge in the development of latent heat storages. Thus, finned heat exchangers (HEX) are often utilized to increase the heat transfer rate of the storage system. In this study, a new modeling approach to calculating the heat transfer rate in latent thermal energy storages with complex HEX geometries is presented. This model allows for an optimization of the HEX design in terms of costs and thermal performance of the system. Modeling solidification processes requires the calculation of time-dependent heat conduction with moving boundaries. Commonly used computational fluid dynamic (CFD) methods enable the analysis of the heat transfer in complex HEX geometries. If applied to the entire storage, the drawback of this approach is the high computational effort due to small time steps and fine computational grids required for accurate solutions. An alternative to describe the process of solidification is the so-called temperature-based approach. In order to minimize the computational effort, a quasi-stationary assumption can be applied. This approach provides highly accurate predictions for tube heat exchangers. However, it shows unsatisfactory results for more complex geometries such as finned tube heat exchangers. The presented simulation model uses a temporal and spatial discretization of heat exchanger tube. The spatial discretization is based on the smallest possible symmetric segment of the HEX. The heat flow in each segment is calculated using finite volume method. Since the heat transfer fluid temperature can be derived using energy conservation equations, the boundary conditions at the inner tube wall is dynamically updated for each time step and segment. The model allows a prediction of the thermal performance of latent thermal energy storage systems using complex HEX geometries with considerably low computational effort.

Keywords: modelling of solidification, finned tube heat exchanger, latent thermal energy storage

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10446 Analysis of Possible Equipment in the Reduction Unit of a Low Tonnage Liquefied Natural Gas Production Plant

Authors: Pavel E. Mikriukov

Abstract:

The demand for natural gas (NG) is increasing every year around the world, so it is necessary to produce and transport NG in large quantities. To solve this problem, liquefied natural gas (LNG) plants are used, using different equipment and different technologies to achieve the required LNG quality. To determine the best efficiency of the LNG liquefaction plant, it is necessary to analyze the equipment used in this process and identify other technological solutions for LNG production using more productive and energy-efficient equipment. Based on this, mathematical models of the technological process of the LNG plant were created, which are based on a two-circuit system of heat exchange equipment and a nitrogen isolated cycle for NG cooling. The final liquefaction of natural gas is performed on the construction of the basic principle of the Joule-Thompson effect. The pressure and temperature drop are considered on different types of equipment such as throttle valve, which was used in the basic scheme; turbo expander and supersonic separator, which act as new equipment, to be compared with the efficiency of the basic scheme of the unit. New configurations of LNG plants are suggested, which can be used in almost all LNG facilities. As a result of the analysis, it turned out that the turbo expander and the supersonic separator have comparatively equal potential in comparison with the baseline scheme execution on the throttle valve. A more rational method of selecting the technology and the equipment used for natural gas liquefaction can improve the efficiency of low-tonnage plants and reduce the cost of gas for own needs.

Keywords: gas liquefaction, gas, Joule-Thompson effect, LNG, low-tonnage LNG, supersonic separator, Throttle valve, turbo expander

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10445 Innovative Housing Construction Technologies in Slum Upgrading

Authors: Edmund M. Muthigani

Abstract:

Innovation in the construction industry has been characterized by new products and processes especially in slum upgrading. The need for low cost housing has motivated stakeholders to think outside the box in coming up with solutions. This paper explored innovative construction technologies that have been used in slum upgrading. The main objectives of the paper was to examine innovations in the construction housing sector and to show how incremental derived demand for decent housing has led to adoption of innovative technologies and materials. Systematic literature review was used to review studies on innovative construction technologies in slum upgrading. The review revealed slow process of innovations in the construction industry due to risk aversion by firms and the hesitance to adopt by firms and individuals. Low profit margins in low cost housing and lack of sufficient political support remain the major hurdles to innovative techniques adoption that can actualize right to decent housing. Conventional construction materials have remained unaffordable to many people and this has negated them decent housing. This has necessitated exploration of innovative materials to realize low cost housing. Stabilized soil blocks and sisal-cement roofing blocks are some of the innovative construction materials that have been utilized in slum upgrading. These innovative materials have not only lowered the cost of production of building elements but also eased costs of transport as the raw materials to produce them are readily available in or within the slum sites. Despite their shortcomings in durability and compressive strength, they have proved worthwhile in slum upgrading. Production of innovative construction materials and use of innovative techniques in slum upgrading also provided employment to the locals.

Keywords: construction, housing, innovation, slum, technology

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10444 Detection the Abundance of Chicken Skin in Hamburger in Tehran

Authors: Ghazanfari Masoumeh, Hajimohammadi Bahador, Eskandari Soheyl, Karimian Khosroshahi Nader

Abstract:

Consumption of ready to cook meat products such as hamburgers, sausages and etc is being increased in the worldwide specially in the big cities , so safety and quality required for food products is very important and vital for consumers with consideration of meat price and increasing demands for meat products, possibility of substitution of cheep and unauthorized textures such as undesirable enclosures animals (massacre, lung tissue, breast of spleen, the organs abdominal cavity, gizzard chicken, skin, etc. ) have increased in the recent years, in this study 30 industrial and 30 handmade hamburgers in fast food restaurants detected out of Iranian national standard for hamburger No. 2304 in using the unauthorized textures. The purpose of this study was to determine using of chicken skin in produced hamburgers from chicken meat in Tehran base on histology methods. The rates of skin used were, 2 % in industrial and 9 % in handmade formula samples. Statistically using the unauthorized textures had significant higher rate in handmade (P < 0.05) in compare with the industrial samples. The results showed the handmade hamburgers with higher adulteration rate and non-compliance with the hamburger national standard could be a potentially health hazard.

Keywords: histology, adulteration, unauthorized textures, undesirable enclosures animals

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10443 The Main Characteristics of Destructive Motivation

Authors: Elen Gasparyan, Naira Hakobyan

Abstract:

One of the leading factors determining the effectiveness of work in a modern organization is the motivation of its employees. In the scientific psychological literature, this phenomenon is understood mainly as constructive forms of motivation and the search for ways to increase it. At the same time, the motivation of employees can sometimes lead to a decrease in the productivity of the organization, i.e., destructive motivation is usually not considered from the point of view of various motivational theories. This article provides an analysis of various forms of destructive motivation of employees. These forms include formalism in labor behavior, inadequate assessment of the work done, and an imbalance of personal and organizational interests. The destructive motivation of personnel has certain negative consequences both for the employees themselves and for the entire organization - it leads to a decrease in the rate of production and the quality of products or services, increased conflict in the behavior of employees, etc. Currently, there is an increase in scientific interest in the study of destructive motivation. The subject of psychological research is not only modern socio-psychological processes but also the achievements of scientific thought in the field of theories of motivation and management. This article examines the theoretical approaches of J. S. Adams and Porter-Lawler, provides an analysis of theoretical concepts, and emphasizes the main characteristics of the destructiveness of motivation. Destructive work motivation is presented at the macro, meso, and micro levels. These levels express various directions of development of motivation stimuli, such as social, organizational, and personal ones. At the macro level, the most important characteristics of destructive motivation are the high-income gap between employers and employees, а high degree of unemployment, weak social protection of workers, non-compliance by employers with labor legislation, and emergencies. At the organizational level, the main characteristics are decreasing the diversity of work and insufficient work conditions. At the personal level, the main characteristic of destructive motivation is a discrepancy between personal and organizational interests. A comparative analysis of the theoretical and methodological foundations of the study of motivation makes it possible to identify not only the main characteristics of destructive motivation but also to determine the contours of psychological counseling to reduce destructiveness in the behavior of employees.

Keywords: destructive, motivation, organization, behavior

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10442 The Last of Centuries Old Cardamom Farming in Eastern Nepal: Crop Disease, Coping Strategies and Institutional Innovation

Authors: K. C. Sony

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This paper investigates the coping strategies of households confronting disease in large cardamom (Amomum Subulatum Roxb.) in eastern Nepal. Cardamom farmers draw on various coping strategies to reduce the impact of crop disease in their livelihoods. Yet farmers face tremendous decline in production with a constant effort for revival. Past evidences provides dearth of information about coping strategies employed by farmers and institutional intervention to combat disease. Using factual data from Ilam district, and conducting a political economic analysis, this research addresses the gap by 1) understanding the impact of crop disease in farmers’ livelihoods, 2) identifying the coping strategies adopted by farmers and, 3) examining the existing institutional arrangements to address the disease. Coping strategies vary by household’s status defined by size of land, alternative income, and access to supporting institutions. Measures adopted are burning the cardamom field, changing land use pattern, diversifying crops, and visiting institutions for support. The local government’s support is limited to providing trainings and producing new varieties of cardamom. During crisis, farmers expect institutions to help revive the cardamom production, despite customary practice to combat disease. To retain and improve the livelihoods of farmers, there needs to be institutional innovation at the community level and policies that endorse immediate and sustainable support during hazards.

Keywords: cardamom, coping strategy, disease, institutions, Nepal

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10441 An Experimental Study on the Optimum Installation of Fire Detector for Early Stage Fire Detecting in Rack-Type Warehouses

Authors: Ki Ok Choi, Sung Ho Hong, Dong Suck Kim, Don Mook Choi

Abstract:

Rack type warehouses are different from general buildings in the kinds, amount, and arrangement of stored goods, so the fire risk of rack type warehouses is different from those buildings. The fire pattern of rack type warehouses is different in combustion characteristic and storing condition of stored goods. The initial fire burning rate is different in the surface condition of materials, but the running time of fire is closely related with the kinds of stored materials and stored conditions. The stored goods of the warehouse are consisted of diverse combustibles, combustible liquid, and so on. Fire detection time may be delayed because the residents are less than office and commercial buildings. If fire detectors installed in rack type warehouses are inadaptable, the fire of the warehouse may be the great fire because of delaying of fire detection. In this paper, we studied what kinds of fire detectors are optimized in early detecting of rack type warehouse fire by real-scale fire tests. The fire detectors used in the tests are rate of rise type, fixed type, photo electric type, and aspirating type detectors. We considered optimum fire detecting method in rack type warehouses suggested by the response characteristic and comparative analysis of the fire detectors.

Keywords: fire detector, rack, response characteristic, warehouse

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10440 An Automatic Speech Recognition of Conversational Telephone Speech in Malay Language

Authors: M. Draman, S. Z. Muhamad Yassin, M. S. Alias, Z. Lambak, M. I. Zulkifli, S. N. Padhi, K. N. Baharim, F. Maskuriy, A. I. A. Rahim

Abstract:

The performance of Malay automatic speech recognition (ASR) system for the call centre environment is presented. The system utilizes Kaldi toolkit as the platform to the entire library and algorithm used in performing the ASR task. The acoustic model implemented in this system uses a deep neural network (DNN) method to model the acoustic signal and the standard (n-gram) model for language modelling. With 80 hours of training data from the call centre recordings, the ASR system can achieve 72% of accuracy that corresponds to 28% of word error rate (WER). The testing was done using 20 hours of audio data. Despite the implementation of DNN, the system shows a low accuracy owing to the varieties of noises, accent and dialect that typically occurs in Malaysian call centre environment. This significant variation of speakers is reflected by the large standard deviation of the average word error rate (WERav) (i.e., ~ 10%). It is observed that the lowest WER (13.8%) was obtained from recording sample with a standard Malay dialect (central Malaysia) of native speaker as compared to 49% of the sample with the highest WER that contains conversation of the speaker that uses non-standard Malay dialect.

Keywords: conversational speech recognition, deep neural network, Malay language, speech recognition

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10439 Bioremediation of Disposed X-Ray Film for Nanoparticles Production

Authors: Essam A. Makky, Siti H. Mohd Rasdi, J. B. Al-Dabbagh, G. F. Najmuldeen

Abstract:

The synthesis of silver nano particles (SNPs) extensively studied by using chemical and physical methods. Here, the biological methods were used and give benefits in research field in the aspect of very low cost (from waste to wealth) and safe time as well. The study aims to isolate and exploit the microbial power in the production of industrially important by-products in nano-size with high economic value, to extract highly valuable materials from hazardous waste, to quantify nano particle size, and characterization of SNPs by X-Ray Diffraction (XRD) analysis. Disposal X-ray films were used as substrate because it consumes about 1000 tons of total silver chemically produced worldwide annually. This silver is being wasted when these films are used and disposed. Different bacterial isolates were obtained from various sources. Silver was extracted as nano particles by microbial power degradation from disposal X-ray film as the sole carbon source for ten days incubation period in darkness. The protein content was done and all the samples were analyzed using XRD, to characterize of silver (Ag) nano particles size in the form of silver nitrite. Bacterial isolates CL4C showed the average size of SNPs about 19.53 nm, GL7 showed average size about 52.35 nm and JF Outer 2A (PDA) showed 13.52 nm. All bacterial isolates partially identified using Gram’s reaction and the results obtained exhibited that belonging to Bacillus sp.

Keywords: nanotechnology, bioremediation, disposal X-ray film, nanoparticle, waste, XRD

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10438 Evaluation of PV Orientation Effect on Mismatch between Consumption Load and PV Power Profiles

Authors: Iyad M. Muslih, Yehya Abdellatif, Sara Qutishat

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Renewable energy and in particular solar photovoltaic energy is emerging as a reasonable power generation source. The intermittent and unpredictable nature of solar energy can represent a serious challenge to the utility grids, specifically at relatively high penetration. To minimize the impact of PV power systems on the grid, self-consumption is encouraged. Self-consumption can be improved by matching the PV power generation with the electrical load consumption profile. This study will focus in studying different load profiles and comparing them to typical solar PV power generation at the selected sites with the purpose of analyzing the mismatch in consumption load profile for different users; residential, commercial, and industrial versus the solar photovoltaic output generation. The PV array orientation can be adjusted to reduce the mismatch effects. The orientation shift produces a corresponding shift in the energy production curve. This shift has a little effect on the mismatch for residential loads due to the fact the peak load occurs at night due to lighting loads. This minor gain does not justify the power production loss associated with the orientation shift. The orientation shift for both commercial and industrial cases lead to valuable decrease in the mismatch effects. Such a design is worth considering for reducing grid penetration. Furthermore, the proposed orientation shift yielded better results during the summer time due to the extended daylight hours.

Keywords: grid impact, HOMER, power mismatch, solar PV energy

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10437 Establishing Forecasts Pointing Towards the Hungarian Energy Change Based on the Results of Local Municipal Renewable Energy Production and Energy Export

Authors: Balazs Kulcsar

Abstract:

Professional energy organizations perform analyses mainly on the global and national levels about the expected development of the share of renewables in electric power generation, heating, and cooling, as well as the transport sectors. There are just a few publications, research institutions, non-profit organizations, and national initiatives with a focus on studies in the individual towns, settlements. Issues concerning the self-supply of energy on the settlement level have not become too wide-spread. The goal of our energy geographic studies is to determine the share of local renewable energy sources in the settlement-based electricity supply across Hungary. The Hungarian energy supply system defines four categories based on the installed capacities of electric power generating units. From these categories, the theoretical annual electricity production of small-sized household power plants (SSHPP) featuring installed capacities under 50 kW and small power plants with under 0.5 MW capacities have been taken into consideration. In the above-mentioned power plant categories, the Hungarian Electricity Act has allowed the establishment of power plants primarily for the utilization of renewable energy sources since 2008. Though with certain restrictions, these small power plants utilizing renewable energies have the closest links to individual settlements and can be regarded as the achievements of the host settlements in the shift of energy use. Based on the 2017 data, we have ranked settlements to reflect the level of self-sufficiency in electricity production from renewable energy sources. The results show that the supply of all the energy demanded by settlements from local renewables is within reach now in small settlements, e.g., in the form of the small power plant categories discussed in the study, and is not at all impossible even in small towns and cities. In Hungary, 30 settlements produce more renewable electricity than their own annual electricity consumption. If these overproductive settlements export their excess electricity towards neighboring settlements, then full electricity supply can be realized on further 29 settlements from renewable sources by local small power plants. These results provide an opportunity for governmental planning of the realization of energy shift (legislative background, support system, environmental education), as well as framing developmental forecasts and scenarios until 2030.

Keywords: energy geography, Hungary, local small power plants, renewable energy sources, self-sufficiency settlements

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10436 Encapsulated Rennin Enzyme in Nano and Micro Tubular Cellulose/Starch Gel Composite for Milk Coagulation

Authors: Eleftheria Barouni, Theano Petsi, Argyro Bekatorou, Dionysos Kolliopoulos, Dimitrios Vasileiou, Panayiotis Panas, Maria Kanellaki, Athanasios A. Koutinas

Abstract:

The aim of the present work was the production and use of a composite filter (TC/starch), containing rennin enzyme, in continuous system and in successive fermentation batches (SFB) for milk coagulation in order to compare the operational stability of both systems and cheese production cost. Tubular cellulose (TC) was produced after removal of lignin from lignocellulosic biomass using several procedures, e.g. alkaline treatment [1] and starch gel was added for the reduction of TC tubes dimensions to micro- and nano- range[2]. Four immobilized biocatalysts were prepared using different ways of the enzyme entrapment. 1) TC/ rennin (rennin entrapped in the tubes of TC), 2) TC/SG-rennin (rennin entrapped in the tubes of the composite), 3) TC-SG/rennin (rennin entrapped into the layer of starch gel) and 4) TC/rennin- SG/rennin (rennin is entrapped both in the tubes of the TC and into the layer of starch gel). Firstly these immobilized biocatalysts were examined in ten SFB regarding the coagulation time and their activity All the above immobilized biocatalysts remained active and the coagulation time was ranged from 90 to 480, 120-480, 330-510, and 270-540 min for (1), (2), (3), and (4) respectively. The quality of the cheese was examined through the determination of volatile compounds by SPME GC/MS analysis. These results encouraged us to study a continuous coagulation system of milk. Even though the (1) immobilized biocatalyst gave lower coagulation time, we used the (2) immobilized biocatalyst in the continuous system. The results were promising.

Keywords: tubular cellulose, starch gel, composite biocatalyst, Rennin, milk coagulation

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10435 Pharmacodynamic Enhancement of Repetitive rTMS Treatment Outcomes for Major Depressive Disorder

Authors: A. Mech

Abstract:

Repetitive transcranial magnetic stimulation has proven to be a valuable treatment option for patients who have failed to respond to multiple courses of antidepressant medication. In fact, the American Psychiatric Association recommends TMS after one failed treatment course of antidepressant medication. Genetic testing has proven valuable for pharmacokinetic variables, which, if understood, could lead to more efficient dosing of psychotropic medications to improve outcomes. Pharmacodynamic testing can identify biomarkers, which, if addressed, can improve patients' outcomes in antidepressant therapy. Monotherapy treatment of major depressive disorder with methylated B vitamin treatment has been shown to be safe and effective in patients with MTHFR polymorphisms without waiting for multiple trials of failed medication treatment for depression. Such treatment has demonstrated remission rates similar to antidepressant clinical trials. Combining pharmacodynamics testing with repetitive TMS treatment with NeuroStar has shown promising potential for enhancing remission rates and durability of treatment. In this study, a retrospective chart review (ongoing) of patients who obtained repetitive TMS treatment enhanced by dietary supplementation guided by Pharmacodynamic testing, displayed a greater remission rate (90%) than patients treated with only NeuroStar TMS (62%).

Keywords: improved remission rate, major depressive disorder, pharmacodynamic testing, rTMS outcomes

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10434 A Greener Approach towards the Synthesis of an Antimalarial Drug Lumefantrine

Authors: Luphumlo Ncanywa, Paul Watts

Abstract:

Malaria is a disease that kills approximately one million people annually. Children and pregnant women in sub-Saharan Africa lost their lives due to malaria. Malaria continues to be one of the major causes of death, especially in poor countries in Africa. Decrease the burden of malaria and save lives is very essential. There is a major concern about malaria parasites being able to develop resistance towards antimalarial drugs. People are still dying due to lack of medicine affordability in less well-off countries in the world. If more people could receive treatment by reducing the cost of drugs, the number of deaths in Africa could be massively reduced. There is a shortage of pharmaceutical manufacturing capability within many of the countries in Africa. However one has to question how Africa would actually manufacture drugs, active pharmaceutical ingredients or medicines developed within these research programs. It is quite likely that such manufacturing would be outsourced overseas, hence increasing the cost of production and potentially limiting the full benefit of the original research. As a result the last few years has seen major interest in developing more effective and cheaper technology for manufacturing generic pharmaceutical products. Micro-reactor technology (MRT) is an emerging technique that enables those working in research and development to rapidly screen reactions utilizing continuous flow, leading to the identification of reaction conditions that are suitable for usage at a production level. This emerging technique will be used to develop antimalarial drugs. It is this system flexibility that has the potential to reduce both the time was taken and risk associated with transferring reaction methodology from research to production. Using an approach referred to as scale-out or numbering up, a reaction is first optimized within the laboratory using a single micro-reactor, and in order to increase production volume, the number of reactors employed is simply increased. The overall aim of this research project is to develop and optimize synthetic process of antimalarial drugs in the continuous processing. This will provide a step change in pharmaceutical manufacturing technology that will increase the availability and affordability of antimalarial drugs on a worldwide scale, with a particular emphasis on Africa in the first instance. The research will determine the best chemistry and technology to define the lowest cost manufacturing route to pharmaceutical products. We are currently developing a method to synthesize Lumefantrine in continuous flow using batch process as bench mark. Lumefantrine is a dichlorobenzylidine derivative effective for the treatment of various types of malaria. Lumefantrine is an antimalarial drug used with artemether for the treatment of uncomplicated malaria. The results obtained when synthesizing Lumefantrine in a batch process are transferred into a continuous flow process in order to develop an even better and reproducible process. Therefore, development of an appropriate synthetic route for Lumefantrine is significant in pharmaceutical industry. Consequently, if better (and cheaper) manufacturing routes to antimalarial drugs could be developed and implemented where needed, it is far more likely to enable antimalarial drugs to be available to those in need.

Keywords: antimalarial, flow, lumefantrine, synthesis

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10433 Changes in the Body Weight and Wound Contraction Rate Following Treatment with Piper betel Extract in Diabetic Wounds

Authors: Nurul Z. Sani, Amalina N. Ghazali, Azree Elmy, Lee C. Yuen, Zar C. Thent

Abstract:

Piper betel (P. betel) leaves is widely used in Asian countries for treating diabetes mellitus and its complication. In our previous study, we observed the positive effect of P.betel extract on diabetic wounds following 3 and 7 days of treatment. The aim of the present study was to determine the effect of P.betel leaves extract in the diabetic rats was observed in terms of body weight and wound contraction rates following 5 days of the treatment. Total 64 male Sprague-Dawley rats were used and the experimental rats received a single dose of 60mg/kg of Streptozotocin (STZ) injection, intraperitoneally. Four full thickness (6mm) cutaneous wounds were created on dorsum of each rat. The rats were divideid into (n=8): Non-treated Control (NC), Non-treated Diabetic (ND), diabetic treated with commercial cream (SN) and diabetic treated with 50mg/kg of P.betel extract (PB). The rats were sacrificed on day 0 and 5 post wounding. Significant increased in wound closure rate, body weight was observed in PB group compared to ND. Histological deterioration was restored in the P. betel extract treated wounds. It is concluded that topical application with P.betel extract for 5 days of post wounding offers positive scientific value in diabetic rats.

Keywords: diabetes, piper betel, wound healing, body weight, morphology

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10432 A Mathematical Analysis of Behavioural Epidemiology: Drugs Users Transmission Dynamics Based on Level Education for Susceptible Population

Authors: Firman Riyudha, Endrik Mifta Shaiful

Abstract:

The spread of drug users is one kind of behavioral epidemiology that becomes a threat to every country in the world. This problem caused various crisis simultaneously, including financial or economic crisis, social, health, until human crisis. Most drug users are teenagers at school age. A new deterministic model would be constructed to determine the dynamics of the spread of drug users by considering level of education in a susceptible population. Based on the analytical model, two equilibria points were obtained; there were E₀ (zero user) and E₁ (endemic equilibrium). Existence of equilibrium and local stability of equilibria depended on the Basic Reproduction Ratio (R₀). This parameter was defined as the expected rate of secondary prevalence and primary prevalence in virgin population along spreading primary prevalence. The zero-victim equilibrium would be locally asymptotically stable if R₀ < 1 while if R₀ > 1 the endemic equilibrium would be locally asymptotically stable. The result showed that R₀ was proportional to the rate of interaction of each susceptible population based on educational level with the users' population. It is concluded that there was a need to be given a control in interaction, so that drug users population could be minimized. Numerical simulations were also provided to support analytical results.

Keywords: drugs users, level education, mathematical model, stability

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10431 Comparative Effects of Homoplastic and Synthetic Pituitary Extracts on Induced Breeding of Heterobranchus longifilis (Valenciennes, 1840) in Indoor Hatchery Tanks in Owerri South East Nigeria

Authors: I. R. Keke, C. S. Nwigwe, O. S. Nwanjo, A. S. Egeruoh

Abstract:

An experiment was carried out at Urban Farm and Fisheries Nigeria Ltd, Owerri Imo State South East Nigeria between February and June 2014 to induce Brood stock of Heterobranchus longifilis (mean wt 1.3kg) in concrete tanks (1.0 x 2.0 x 1.5m) in dimension using a synthetic hormone (Ovaprim) and pituitary extract from Heterobranchus longifilis. Brood stock males were selected as pituitary donors and their weights matched those of females to be injected at 1ml/kg body weight of Fish. Ovaprim, was injected at 0.5ml/kg body weight of female fish. A latency period of 12 hours was allowed after injection of the Brood stock females before stripping the egg and incubation at 23 °C. While incubating the eggs, samples were drawn and the rate of fertilization was determined. Hatching occurred within 33 hours and hatchability rate (%) was determined by counting the active hatchings. The result showed that Ovaprim injected Brood stock eggs fertilized up to 80% while the pituitary from the Heterobranchus longifilis had low fertilization and hatching success 20%. Ovaprim is imported and costly, so more effort is required to enhance the procedures for homoplastic hypophysation.

Keywords: heterobranchus longifilis, ovaprim, hypophysation, latency period, pituitary

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10430 A Computational Fluid Dynamics Simulation of Single Rod Bundles with 54 Fuel Rods without Spacers

Authors: S. K. Verma, S. L. Sinha, D. K. Chandraker

Abstract:

The Advanced Heavy Water Reactor (AHWR) is a vertical pressure tube type, heavy water moderated and boiling light water cooled natural circulation based reactor. The fuel bundle of AHWR contains 54 fuel rods arranged in three concentric rings of 12, 18 and 24 fuel rods. This fuel bundle is divided into a number of imaginary interacting flow passage called subchannels. Single phase flow condition exists in reactor rod bundle during startup condition and up to certain length of rod bundle when it is operating at full power. Prediction of the thermal margin of the reactor during startup condition has necessitated the determination of the turbulent mixing rate of coolant amongst these subchannels. Thus, it is vital to evaluate turbulent mixing between subchannels of AHWR rod bundle. With the remarkable progress in the computer processing power, the computational fluid dynamics (CFD) methodology can be useful for investigating the thermal–hydraulic characteristics phenomena in the nuclear fuel assembly. The present report covers the results of simulation of pressure drop, velocity variation and turbulence intensity on single rod bundle with 54 rods in circular arrays. In this investigation, 54-rod assemblies are simulated with ANSYS Fluent 15 using steady simulations with an ANSYS Workbench meshing. The simulations have been carried out with water for Reynolds number 9861.83. The rod bundle has a mean flow area of 4853.0584 mm2 in the bare region with the hydraulic diameter of 8.105 mm. In present investigation, a benchmark k-ε model has been used as a turbulence model and the symmetry condition is set as boundary conditions. Simulation are carried out to determine the turbulent mixing rate in the simulated subchannels of the reactor. The size of rod and the pitch in the test has been same as that of actual rod bundle in the prototype. Water has been used as the working fluid and the turbulent mixing tests have been carried out at atmospheric condition without heat addition. The mean velocity in the subchannel has been varied from 0-1.2 m/s. The flow conditions are found to be closer to the actual reactor condition.

Keywords: AHWR, CFD, single-phase turbulent mixing rate, thermal–hydraulic

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10429 Optimization of Cutting Parameters on Delamination Using Taguchi Method during Drilling of GFRP Composites

Authors: Vimanyu Chadha, Ranganath M. Singari

Abstract:

Drilling composite materials is a frequently practiced machining process during assembling in various industries such as automotive and aerospace. However, drilling of glass fiber reinforced plastic (GFRP) composites is significantly affected by damage tendency of these materials under cutting forces such as thrust force and torque. The aim of this paper is to investigate the influence of the various cutting parameters such as cutting speed and feed rate; subsequently also to study the influence of number of layers on delamination produced while drilling a GFRP composite. A plan of experiments, based on Taguchi techniques, was instituted considering drilling with prefixed cutting parameters in a hand lay-up GFRP material. The damage induced associated with drilling GFRP composites were measured. Moreover, Analysis of Variance (ANOVA) was performed to obtain minimization of delamination influenced by drilling parameters and number layers. The optimum drilling factor combination was obtained by using the analysis of signal-to-noise ratio. The conclusion revealed that feed rate was the most influential factor on the delamination. The best results of the delamination were obtained with composites with a greater number of layers at lower cutting speeds and feed rates.

Keywords: analysis of variance, delamination, design optimization, drilling, glass fiber reinforced plastic composites, Taguchi method

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10428 Factors Influencing Milk Yield, Quality, and Revenue of Dairy Farms in Southern Vietnam

Authors: Ngoc-Hieu Vu

Abstract:

Dairy production in Vietnam is a relatively new agricultural activity and milk production increased remarkably in recent years. Smallholders are still the main drivers for this development, especially in the southern part of the country. However, information on the farming practices is very limited. Therefore, this study aimed to determine factors influencing milk yield and quality (milk fat, total solids, solids-not-fat, total number of bacteria, and somatic cell count) and revenue of dairy farms in Southern Vietnam. The collection of data was at the farm level; individual animal records were unavailable. The 539 studied farms were located in the provinces Lam Dong (N=111 farms), Binh Duong (N=69 farms), Long An (N=174 farms), and Ho Chi Minh city (N=185 farms). The dataset included 9221 monthly test-day records of the farms from January 2013 to May 2015. Seasons were defined as rainy and dry. Farms sizes were classified as small (< 10 milking cows), medium (10 to 19 milking cows) and large (≥ 20 milking cows). The model for each trait contained year-season and farm region-farm size as subclass fixed effects, and individual farm and residual as random effects. Results showed that year-season, region, and farm size were determining sources of variation affecting all studied traits. Milk yield was higher in dry than in rainy seasons (P < 0.05), while it tended to increase from years 2013 to 2015. Large farms had higher yields (445.6 kg/cow) than small (396.7 kg/cow) and medium (428.0 kg/cow) farms (P < 0.05). Small farms, in contrast, were superior to large farms in terms of milk fat, total solids, solids-not-fat, total number of bacteria, and somatic cell count than large farms (P < 0.05). Revenue per cow was higher in large compared with medium and small farms. In conclusion, large farms achieved higher milk yields and revenues per cow, while small farms were superior in milk quality. Overall, milk yields were low and better training, financial support and marketing opportunities for farmers are needed to improve dairy production and increase farm revenues in Southern Vietnam.

Keywords: farm size, milk yield and quality, season, Southern Vietnam

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10427 Investigation of Chemical Effects on the Lγ2,3 and Lγ4 X-ray Production Cross Sections for Some Compounds of 66dy at Photon Energies Close to L1 Absorption-edge Energy

Authors: Anil Kumar, Rajnish Kaur, Mateusz Czyzycki, Alessandro Migilori, Andreas Germanos Karydas, Sanjiv Puri

Abstract:

The radiative decay of Li(i=1-3) sub-shell vacancies produced through photoionization results in production of the characteristic emission spectrum comprising several X-ray lines, whereas non-radiative vacancy decay results in Auger electron spectrum. Accurate reliable data on the Li(i=1-3) sub-shell X-ray production (XRP) cross sections is of considerable importance for investigation of atomic inner-shell ionization processes as well as for quantitative elemental analysis of different types of samples employing the energy dispersive X-ray fluorescence (EDXRF) analysis technique. At incident photon energies in vicinity of the absorption edge energies of an element, the many body effects including the electron correlation, core relaxation, inter-channel coupling and post-collision interactions become significant in the photoionization of atomic inner-shells. Further, in case of compounds, the characteristic emission spectrum of the specific element is expected to get influenced by the chemical environment (coordination number, oxidation state, nature of ligand/functional groups attached to central atom, etc.). These chemical effects on L X-ray fluorescence parameters have been investigated by performing the measurements at incident photon energies much higher than the Li(i=1-3) sub-shell absorption edge energies using EDXRF spectrometers. In the present work, the cross sections for production of the Lk(k= γ2,3, γ4) X-rays have been measured for some compounds of 66Dy, namely, Dy2O3, Dy2(CO3)3, Dy2(SO4)3.8H2O, DyI2 and Dy metal by tuning the incident photon energies few eV above the L1 absorption-edge energy in order to investigate the influence of chemical effects on these cross sections in presence of the many body effects which become significant at photon energies close to the absorption-edge energies. The present measurements have been performed under vacuum at the IAEA end-station of the X-ray fluorescence beam line (10.1L) of ELETTRA synchrotron radiation facility (Trieste, Italy) using self-supporting pressed pellet targets (1.3 cm diameter, nominal thicknesses ~ 176 mg/cm2) of 66Dy compounds (procured from Sigma Aldrich) and a metallic foil of 66Dy (nominal thickness ~ 3.9 mg/cm2, procured from Good Fellow, UK). The present measured cross sections have been compared with theoretical values calculated using the Dirac-Hartree-Slater(DHS) model based fluorescence and Coster-Kronig yields, Dirac-Fock(DF) model based X-ray emission rates and two sets of L1 sub-shell photoionization cross sections based on the non-relativistic Hartree-Fock-Slater(HFS) model and those deduced from the self-consistent Dirac-Hartree-Fock(DHF) model based total photoionization cross sections. The present measured XRP cross sections for 66Dy as well as for its compounds for the L2,3 and L4 X-rays, are found to be higher by ~14-36% than the two calculated set values. It is worth to be mentioned that L2,3 and L4 X-ray lines are originated by filling up of the L1 sub-shell vacancies by the outer sub-shell (N2,3 and O2,3) electrons which are much more sensitive to the chemical environment around the central atom. The present observed differences between measured and theoretical values are expected due to combined influence of the many-body effects and the chemical effects.

Keywords: chemical effects, L X-ray production cross sections, Many body effects, Synchrotron radiation

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