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排序方式: 共有117条查询结果,搜索用时 46 毫秒
1.
Tareq Salameh Mohammad Ali Abdelkareem A.G. Olabi Enas Taha Sayed Monadhil Al-Chaderchi Hegazy Rezk 《International Journal of Hydrogen Energy》2021,46(8):6014-6027
Renewable energy resources play a very important rule these days to assist the conventional energy systems for doing its function in the UAE due to high greenhouse gas (GHG) emissions and energy demand. In this paper, the analysis and performance of integrated standalone hybrid solar PV, fuel cell and diesel generator power system with battery energy storage system (BESS) or supercapacitor energy storage system (SCESS) in Khorfakkan city, Sharjah were presented. HOMER Pro software was used to model and simulate the hybrid energy system (HES) based on the daily energy consumption for Khorfakkan city. The simulation results show that using SCESS as an energy storage system will help the performance of HES based on the Levelized cost of energy (LCOE) and greenhouse gas (GHG) emissions. The HES with SCESS has renewable fraction (68.1%) and 0.346 $/kWh LCOE. The HES meets the annual AC primary load of the city (13.6 GWh) with negligible electricity excess and with an unmet electrical load of 1.38%. The reduction in GHG emissions for HES with SCESS was 83.2%, equivalent to saving 814,428 gallons of diesel. 相似文献
2.
Synthesis and evaluation of the thermal properties of biosourced poly(ether)ureas and copoly(ether)ureas from 1,4:3,6‐dianhydrohexitols 下载免费PDF全文
Raouf Medimagh Maissa Meddeb Smaidia Haythem Bennour Saber Chatti 《Polymer International》2015,64(4):513-520
A new series of poly(ether)ureas were prepared by solution polyaddition of three diamines based on 1,4:3,6‐dianhydrohexitols with three types of diisocyanate. The corresponding poly(ether)ureas were obtained with high yields. They were characterized by various analytical techniques (NMR, TGA and differential thermal analysis, DSC). NMR spectroscopy allowed us to confirm structure type and to optimize reaction conditions and DSC proved the high thermal properties of the products obtained (Tg and Tm in the range 126 ? 158 °C and 235 ? 330 °C respectively). Then, copoly(ether)ureas partially based on commercial diamines were synthesized in order to reduce polymer cost and tune their thermal behaviour. The reactivity of both diamines was evaluated by their incorporation in the polymer by means of NMR spectra. Then their thermal properties were compared with fully commercial diamine based polyureas by DSC studies. © 2014 Society of Chemical Industry 相似文献
3.
Rosa Colucci Cante Marianna Gallo Federica Nigro Francesca Passannanti Dana Salameh Andrea Budelli Roberto Nigro 《加拿大化工杂志》2020,98(9):1955-1961
In recent years, scientific interest in the development of non-dairy-based functional foods is increasing progressively and the fermentation of cereals, legumes, fruits and vegetable-based foods is becoming an important scientific research topic for the production of new probiotic products. In particular, legumes represent a possible alternative to protein foods from animal origins and an adequate fermentation substrate as they contain high amount of nutrients, such as proteins, carbohydrates, fibres, vitamins, and minerals, which are all useful to the growth and metabolic activity of certain microorganisms. This work focuses on the feasibility of developing a dry legume-based functional product using a fermentation process carried out on a 10% w/v navy bean suspension, in a lab-scale stirred batch reactor. After soaking and cooking dried navy beans, the fermentation tests performed on the resulting medium using Lactobacillus paracasei CBA L74 showed a maximum bacterial count of 109 CFU/mL after 20 hours and a maximum lactic acid concentration of 1.9 g/L after 16 hours of process time. A freeze-drying process was performed on the fermented bean suspension, showing a 2-log microbial reduction and a bacterial viability in the resulting probiotic powder of 3.7 × 108 CFU/g. 相似文献
4.
Bany Salameh Haythem Al-Nusair Noor Alnabelsi Sharhabeel H. Darabkh Khalid A. 《Wireless Networks》2020,26(6):4477-4489
Wireless Networks - Cognitive radio (CR) is a promising technology that allows devices to effectively utilize the underutilized or unutilized portions of the licensed spectrum. In literature,... 相似文献
5.
Elias Salameh 《The International journal of environmental studies》2013,70(4):291-300
Two main problems seem to face the use of surface water for domestic purposes in semi‐arid regions. These problems are eutrophication of surface water bodies and the formation of chlorinated hydrocarbons during water treatment. Both problems develop as direct of indirect results of anthropogenic activities. The eutrophication problem will be discussed with reference to King Talal Reservoir, whereas the formation of chlorinated hydrocarbons will be illustrated when discussing the use of the East Ghor Canal water for domestic purposes. 相似文献
6.
To ensure the maximum financial performance of organizations in rapidly changing environments, the coordination between strategic management objectives and information systems capabilities is of fundamental importance. This article proposes a conceptual framework for linking these 2 elements and suggests 10 hypotheses regarding this subject that merit further investigation by MIS managers. 相似文献
7.
The current access policies and funding schemes of computing e-infrastructures represent a huge challenge for the sustainable growth of computing e-infrastructures and a serious jeopardy for investments made into these e-infrastructures. In order to be able to address these issues, the economics of computing e-infrastructures has to be understood thoroughly. As a first step in this direction, this paper conducts a set of computing e-infrastructure case studies and discusses the economic issues of different global computing e-infrastructure efforts. The analyses results show that the major shortcomings that need to be resolved are the insufficient involvement of the private sector in the development of computing e-infrastructures, the restricted user access to e-infrastructure resources, and the lack of sustainable funding. As a solution to these shortcomings, we propose a new funding and governing model for computing e-infrastructures. It follows a token-based market mechanism that allows a business-oriented operation of the computing e-infrastructure. We argue that this new model fosters the transition towards a sustainable computing e-infrastructure, being another requirement for successfully implementing the cloud computing vision. Our arguments are supported by an analytical analysis. 相似文献
8.
Waterpipe smoking is becoming fashionable in Lebanon, but no studies have studied nicotine dependence related to waterpipe smoking. A score was constructed from 21 items and subsequently submitted to two factor analyses, which led to the extraction of four factors. Reliability and test-retest reproducibility were measured. Convergent construct validity and discriminant validity also were assessed for different smokers' samples. The Lebanon Waterpipe Dependence Scale-11 (LWDS-11) was composed of four subscales, the first representing nicotine dependence, the second negative reinforcement, the third psychological craving, and the fourth positive reinforcement. Internal consistency and test-retest reproducibility were adequate, and the subscales correlated adequately with measurements of nicotine metabolites, exhaled carbon monoxide levels, and the frequency of waterpipe smoking. The LWDS-11 discriminated between mild, moderate, and heavy waterpipe smokers, based on a threshold score of 10. Results were biologically and psychologically sound. This is the first scale to characterize waterpipe dependence. With further improvement and confirmation, it could become a useful clinical and epidemiological tool. 相似文献
9.
The STM-5-140 nickel cadmium electric vehicle battery was tested under actual operating conditions using the UMASS Lowell battery evaluation laboratory. The battery evaluation system uses battery current data taken from an EV using its on board data acquisition system. The car is driven on a typical commute while battery current as well as other data are taken at one second intervals. In the battery evaluation lab, individual batteries are subjected to the same operating conditions as those in the car. This procedure uses fewer batteries and allows the same commute to be repeated exactly. Three test procedures using 0, 20, and 40 degree centigrade controlled environment temperatures were implemented. Measured data consisted of voltage, current, and temperature. Test cycle, capacity and round trip efficiency data are presented 相似文献
10.
The performance of a photovoltaic powered health clinic system designed, built, and evaluated at the University of Lowell is investigated. This system uses two separate batteries, one to power a vaccine refrigerator and the other to power auxiliary loads. The two batteries were sized according to the demand of their loads. The power control system utilizes a five-stage dual priority controller to charge the two separate batteries from a single modular photovoltaic array. The main refrigerator battery always has priority over the auxiliary battery; therefore, the use of auxiliary loads will never jeopardize the reliability of the critical load. This system provides power for auxiliary loads while utilizing the same number of photovoltaic modules as systems which power only a vaccine refrigerator. The performance of this system was evaluated using a data acquisition system, and the experimental results are compared with theoretical values 相似文献