555 research outputs found
Sustainable Development and Environmentally Friendly Energy Systems
People are relying upon oil for primary energy and this will continue for a few more decades. Other conventional sources may be more enduring but are not without serious disadvantages. The renewable energy resources are particularly suited for the provision of rural power supplies and a major advantage is that equipment such as flat plate solar driers, wind machines, etc., can be constructed using local resources. Without the advantage results from the feasibility of local maintenance and the general encouragement, such local manufacture gives to the buildup of a small-scale rural-based industry. This communication comprises a comprehensive review of energy sources, the environment, and sustainable development. It includes the renewable energy technologies, energy efficiency systems, energy conservation scenarios, energy savings in greenhouses environment and other mitigation measures necessary to reduce climate change. This study gives some examples of small-scale energy converters, nevertheless, it should be noted that small conventional, i.e., engines are currently the major source of power in rural areas and will continue to be so for a long time to come
Promotion and Implementation of Bioenergy for a Better Environment
- There is strong scientific evidence that the average temperature of the earth's surface is rising and this may be attribute to increased concentration of carbon dioxide (CO2), and other greenhouse gases (GHGs) in the atmosphere as released by burning fossil fuels. One of the chief sources of greenhouse gases is burning of fossil fuels. Biogas from biomass appears to have potential as an alternative energy source, which is potentially rich in biomass resources. In the present paper, current literature is reviewed regarding the ecological, social, cultural and economic impacts of biogas technology. In this article an attempt has been made to give an overview of present and future use of biomass as an industrial feedstock for production of fuels, chemicals and other materials. However, to be truly competitive in an open market situation, higher value products are required
Performance, Modeling, Measurements, and Simulation of Energy Efficient for Heat Exchanger, Refrigeration and Air Conditioning
Over the years, all parts of a commercial refrigerator, such as the compressor, heat exchangers, refrigerant, and packaging, have been improved considerably due to the extensive research and development efforts carried out by academia and industry. However, the achieved and anticipated improvement in conventional refrigeration technology are incremental since this technology is already nearing its fundamentals limit of energy efficiency is described is ‘magnetic refrigeration\u27 which is an evolving cooling technology. The word ‘green\u27 designates more than a color. It is a way of life, one that is becoming more and more common throughout the world. An interesting topic on ‘sustainable technologies for a greener world\u27 details about what each technology is and how it achieves green goals. Recently, conventional chillers using absorption technology consume energy for hot water generator but absorption chillers carry no energy saving. With the aim of providing a single point solution for this dual-purpose application, a product is launched but can provide simultaneous chilling and heating using its vapor absorption technology with 40% saving in heating energy. Using energy efficiency and managing customer energy use has become an integral and valuable exercise. The reason for this is green technology helps to sustain life on earth. This not only applies to humans but to plants, animals and the rest of the ecosystem. Energy prices and consumption will always be on an upward trajectory. In fact, energy costs have steadily risen over last decade and are expected to carry on doing so as consumption grows
Microbial-Physical Synthesis of Fe and Fe3O4 Magnetic Nanoparticles Using Aspergillus niger YESM1 and Supercritical Condition of Ethanol
Magnetic Fe and Fe3O4 (magnetite) nanoparticles are successfully synthesized using Aspergillus niger YESM 1 and supercritical condition of liquids. Aspergillus niger is used for decomposition of FeSO4 and FeCl3 to FeS and Fe2O3, respectively. The produced particles are exposed to supercritical condition of ethanol for 1 hour at 300∘ C and pressure of 850 psi. The phase structure and the morphology measurements yield pure iron and major Fe3O4 spherical nanoparticles with average size of 18 and 50 nm, respectively. The crystal size amounts to 9 nm for Fe and 8 nm for Fe3O4. The magnetic properties are measured to exhibit superparamagneticand ferromagnetic-like behaviors for Fe and Fe3O4 nanoparticles, respectively. The saturation magnetization amounts to 112 and 68 emu/g for Fe and Fe3O4, respectively. The obtained results open new route for using the biophysical method for large-scale production of highly magnetic nanoparticles to be used for biomedical applications
An approximate analytical formula for estimating the weight of factors affecting the spread of COVID-19: a case study of the first wave
COVID-19 pandemic has changed the way we live our lives for the foreseen future. To date, there have been over 113 million reported cases and 2.5 million deaths worldwide. Many studies investigated the factors affecting the number of daily cases such as weather conditions, lockdown duration and other factors. In this study, we propose a COVID-19 analytical formula for factors contributing to the number of the new coronavirus daily cases. We have also calculated values of relative weights of those factors. We focus on the first wave data that are publically available. Seven countries were considered including the UK, Italy, Spain, Canada, South Korea, Germany and France. We considered the following factors: temperature, humidity, government expenditure, lockdown hours and the number of daily tests for COVID-19 performed. The weights were calculated based on the hypothesis that a high correlation between recorded data of a given pair of countries implies a high correlation of the pair’s COVID-19 proposed analytical formula. The factors are calculated using the brute-force technique. Our results showed that in five out of the seven countries; temperature, humidity, and lockdown duration were the most dominant with values of 26%, 32% and 38%, respectively. In other countries, however, humidity, government expenditure and the daily performed tests for COVID-19 were the most effective factors, with relative values of 35%, 26%, and 28%
Time varying rotating disk flow and heat transfer through a porous medium of a non-Newtonian fluid with suction and injection
The time varying flow of an incompressible viscous non-Newtonian fluid above an infinite rotating porous disk in a porous medium is studied with heat transfer. A uniform injection or suction is applied through the surface of the disk. Numerical solutions of the nonlinear partial differential equations which govern the hydrodynamics and energy transfer are obtained. The effect of the porosity of the medium, the characteristics of the non-Newtonian fluid and the suction or injection velocity on the velocity and temperature fields is considered
Foliar application of chitosan zinc oxide nanoparticles on wheat productivity and water use efficiency under deficit irrigation water
The effectiveness of chitosan zinc oxide nanoparticles (CS-ZnO-NPs) on growth and yield of wheat (Triticum aestivum L., Sakha-93), zinc content and water use efficiency (WUE) under water stress were investigated. A pot experiment was conducted in a completely randomized design by foliar application of CS-ZnO-NPs. Wheat plants were sprayed four times at 15, 30, 45 and 60 days after sowing. The treatments were: control (treated with distilled water), 50, 100 and 150 ppm of CS-ZnO-NPs under 100, 80 and 60% of field capacity. Water shortage has a negative effect on growth parameters and productivity of wheat plants. While the foliar application of 150 ppm CS-ZnO-NPs significantly increased (P≤0.05) NPK content, growth parameters which in turn led to increase the productivity. The highest values of wheat yield were: 4990.55, 4453.50 and 4350.50 kg/ha under 100 80 and 60% of irrigation water, respectively at 150 ppm CS-ZnO-NPs. The highest values of N, P and K content in wheat grain were 1.95, 0.43 and 1.66, respectively at 100% FC under150 ppm CS-ZnO-NPs compared to control. Zn content in wheat grain significantly increased (P≤0.05) by application of CS-ZnO NPs. The interaction of supplementary irrigation water and CS-ZnO-NPs treatments gave clear variation in water use efficiency. The highest relative increase of WUE (23.03%) was at the highest rate of CS-ZnO-NPs (150 ppm). Overall, the data suggested that the foliar application of CS-ZnO-NPs can be an efficient strategy for improving wheat yield, water use efficiency under deficit water and one of the solutions for Zn deficiency in wheat grains
Molecular characterization of Anaplasma and Ehrlichia in ixodid ticks and reservoir hosts from Palestine: a pilot survey
Tick-borne anaplasmosis and ehrlichiosis are clinically important emerging zoonoses usually overlooked by veterinarians and physicians alike. This study aimed at detecting and genetically characterizing Ehrlichia and Anaplasma species in ixodid ticks and their animal hosts from the West Bank, Palestine. A total of 723 ixodid ticks belonging to three genera (Rhipicephalus, Hyalomma, Haemaphysalis) were collected from dogs, sheep, goats and camels. In addition, 189 blood samples were collected from dogs, sheep, camels, horses and a goat from the West Bank, Palestine. All tick and blood samples were investigated for the presence of Anaplasma and Ehrlichia targeting a 345 bp fragment of the 16S rRNA gene followed by sequence analysis. The infection rate of Anaplasma spp. in ticks was 6.5% (47/723). Anaplasma platys was identified in 28% (13/47) of them. Whereas, based on a partial sequence (851 bp) of msp4 gene, 38% (18/47) were identified as A. ovis. The species of the remaining 16 positive samples (16/47, 34%) could not be identified. Simultaneously, the infection rate of Ehrlichia spp. in the ticks was 0.6% (4/723). Three of which were E. canis and one was Ehrlichia spp. The infection rate of A. platys in dogs' blood samples was 10% (13/135), while it was 1.5% (2/135) for E. canis. The infection rate of Anaplasma in sheep blood samples was 40% (19/47), out of which 26% (5/19) were caused by A. ovis as revealed by msp4-PCR. Implementation of purely-spatial analysis by saTScan for all cases of Anaplasma revealed two statistically significant clusters in two districts; Tubas town and Majdal-Bani-Fadil village on the western hills of the Jordan Valley. Most cases of Anaplasma (83%) were from rural areas where life cycle components (vector, host and reservoir) abundantly interact. This study is the first in Palestine to reveal the presence of Anaplasma and Ehrlichia in ticks, dogs and sheep providing crucial platform for future epidemiological surveys and control strategies in the country and regio
Bartonella Species in Fleas from Palestinian Territories: Prevalence and Genetic Diversity
Bartonellosis is an infectious bacterial disease. The prevalence and genetic characteristics of Bartonella spp. in fleas
of wild and domestic animals from Palestinian territories are described. Flea samples (n=289) were collected from 121 cats,
135 dogs, 26 hyraxes and seven rats from northern (n=165), central (n=113), and southern Palestinian territories (n=11). The
prevalent flea species were: Ctenocephalides felis (n=119/289; 41.2%), Ctenocephalides canis (n=159/289; 55%), and Xenopsylla sp. (n=7/289; 2.4%). Targeting the Intergenic Transcribed Spacer (ITS) locus, DNA of Bartonella was detected in 22% (64/289) of all fleas. Fifty percent of the C. felis and 57% of the Xenopsylla sp. contained Bartonella DNA. DNA sequencing showed the presence of Bartonella clarridgeiae (50%), Bartonella henselae (27%), and Bartonella koehlerae (3%) in C. felis. Xenopsylla sp. collected from Rattus rattus rats were infected with Bartonella tribocorum, Bartonella elizabethae, and Bartonella rochalimae. Phylogenetic sequence analysis using the 16S ribosomal RNA gene obtained four genetic clusters, B. henselae and B. koehlerae as subcluster 1, B. clarridgeiae as cluster 2, while the rat Bartonella species (B. tribocorum and B. elizabethae) were an outgroup cluster. These findings showed the important role of cat and rat fleas as vectors of zoonotic Bartonella species in Palestinian territories. It is hoped that this publication will raise awareness among physicians, veterinarians, and other health workers of the high prevalence of Bartonella spp. in fleas in Palestinian territories and the potential risk of these pathogens to humans and animals in this region.This study was a partial fulfillment of MSc degree in the
biochemistry and molecular biology program for A. Risheq
at Al-Quds University. The study was funded by The Ministry
of Foreign Affairs, The Hague, The Netherlands, project M27-
072NVHU 2009 02 ‘Vector-Borne Pathogens in Israel and the
Palestinian Authority’
Analytic Investigation and Numeric Prediction for Biodynamic Response of the Seated Human Body
Abstract: The biodynamic response behaviors of seated human body subject to whole-body vibration have been widely investigated. The biodynamic response characteristics of seated human subjects have been extensively reported in terms of apparent mass and driving-point mechanical impedance while seat-to-head vibration transmissibility has been widely used to characterize response behavior of the seated subjects exposed to vibration. These functions (apparent mass, driving-point mechanical impedance) describe "to-the-body" force-motion relationship at the human-seat interface, while the transmissibility function describes "through-the-body" vibration transmission properties. The current study proposed a 4-DOF analytic biomechanical model of the human body in a sitting posture without backrest in vertical vibration direction to investigate the biodynamic responses of different masses and stiffness. Following the analytical approach, numerical technique developed in the present paper to facilitate and rapid the analysis. The numerical analysis used here applies one of the artificial intelligence technique to simulate and predict the response behaviors of seated human body for different masses and stiffness without the need to go through the analytic solution every time. The Artificial Neural Network (ANN) technique is introduced in the current study to predict the response behaviors for different masses and stiffness rather than those used in the analytic solution. The results of the numerical study showed that the ANN method with less effort was very efficiently capable of simulating and predicting the response behaviors of seated human body subject to whole-body vibration
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