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Structural Studies on Ag2O-P2O5Glasses

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New Journal of Glass and Ceramics 2017年第3期7卷 77-89页

作者： Gomaa El-Damrawi Abdelmajued Hassan Hamdy Doweidar ahamed Shaboub Glass Research Group Physics Department Faculty of Science Mansoura University Mansoura Egypt

Silver phosphate glasses of general formula xAg2O·(100 - x)P2O5 have been investigated over compositional range from x = 40 to 62.5 mol%. The local structure around phosphorus atom has been studied via 31P nuclear magnetic resonance. The distribution of [PO4]Qn species as a function of composition has been shown to slightly deviate from the simple binary alkali phosphate model. An anomalous behavior has been recorded and interpreted in terms of mixed ring-chain effect in metaphosphate composition. The splitting of NMR spectra into sub resonances is assigned to different binding sites characterizing Q1 ring and Q1 chain structure. Higher Ag2O concentration (≥50 mol%) leads to formation of phosphate groups with specific resonance peaks which are mainly related to pyro and orthophosphate species. The rate of change of the chemical shift of the 31P NMR depends on the bond type, which in turn reflects the extent of double bonding between phosphorus and oxygen atoms. Increasing concentration of Q0 with increasing Ag2O content leads to decreasing quantities of bridging and double bonds. As a consequence, specific symmetric resonance peak of higher intensity and chemical shift (Q0) is a feature of silver rich glasses (orthophosphate). The latter species is therefore proposed to compose of separated membered rings,?which cause deshielding of phosphate units.?XRD and EDP studies have shown that, amorphous phosphate network is the dominant structure of glasses containing ≤ 55 mol% Ag2O. Some ordered and well crystallized phases are formed at higher Ag2O concentration. Increasing non-bridging oxygen atoms is shown to have the main effect on crystallization behavior. Orthophosphate composition is the most crystalline one among the other compositions (ultra, meta- and pyrophosphate). Presence of orthophosphate species which typically contains highest concentration from isolated Q0 units is the main reason for building up crystalline Ag3PO4phosphate phase.

关键词： Nuclear Magnetic Resonance Chemical Shift Phosphate Species Orthophosphates

Evaluate the Strength of Denim Goods Using Different Washing Technique

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Journal of Materials Science and Chemical Engineering 2021年第3期9卷 1-8页

作者： Jakaria ahamed Md. Faysal Mahmud Md. Faysal Ahammed Rony Mia Md. Zahid Hasan Tarequl Hasan Khan Golam Qibria Limon al Mojnun Shamim Department of Textile Engineering National Institute of Textile Engineering & Research (NITER) Savar Dhaka Bangladesh School of Textile Science & Engineering Wuhan Textile University Wuhan China College of Chemistry & Chemical Engineering Wuhan Textile University Wuhan China

Day by day, the demand and popularity of denim have increased. With the increase in demand for denim, washing has also increased. When we washed a piece of denim fabric, then its properties also changed. The properties are tensile strength, GSM, color fading, stiffness, abrasion resistance, moisture regain, etc. In this study, we conduct different washing processes on denim fabric such are Stonewash, Caustic wash, Acid wash, Normal wash, Pigment wash, Sandblasting, and Super whitewash. After washing, the properties of denim fabric have been analyzed especially strength. The tear and tensile strength were measured by ISO standard. From the above washing method, Normal & pigment wash showed good strength properties comparing with others.

关键词： Denim Fabric Washing Treatment Tear Strength Tensile Strength Normal Wash Pigment Wash

应用距离估计及露营数计数确定UE在异构网络的移动状态

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应用距离估计及露营数计数确定UE在异构网络的移动状态

作者： Mohamed Abdelbagi Gailani ahamed 中国地质大学（北京）

学位级别：硕士

现今社会,通信运营商一直致力于给用户提供最好的服务,异构网络的应用成为了关键,移动应用设备需要利用其异质性。在多媒体传输及数据传输中异机种网络和其网络协议包含了基础通信协议,在移动通信中起着关键性作用。本课题基于华为技术... 详细信息

现今社会,通信运营商一直致力于给用户提供最好的服务,异构网络的应用成为了关键,移动应用设备需要利用其异质性。在多媒体传输及数据传输中异机种网络和其网络协议包含了基础通信协议,在移动通信中起着关键性作用。本课题基于华为技术有限公司无线网络通信实验室已有理论及技术,分析研究已有移动通信技术,提出应用距离估计及露营数计数确定用户设备在异构网络的移动状态,并对此方法开展研究及实验。本文提供了一种所需的用户设备的移动性状态检测方法。通过基站,系统信息确定位于当前小区和以前小区位置的小区地理(坐标)的单元格标识符(ID);从这个信息得知,使用终端内的细胞之间的距离估计方法,包括计算在当前时刻的终端的总体移动距离,并确定在复杂的网络体系结构中站的状态移动性距离。也可以计算一个小区重选或小区切换的数量,能够通过利用计算出的移动性状态的小区重选或切换为在终端宏小区的数值量,通过两种情况下计算出的小区标识符(ID),提高显示移动状态的性能和网络性能的异构和同构。课题对这一方法进行了仿真验证,从仿真结果证明了所设计方法达到了预期效果。

关键词：移动状态 HetNet和HomoNet 距离估计确定流动状态计数露营的人数

Si_3P_4各种相的结构、电子和弹性性质(英文)

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西南大学学报（自然科学版） 2007年第5期29卷 1-8页

作者： A.S.ahamed 陈洪袁宏宽西南大学物理科学与技术学院重庆400715

采用密度泛函理论的定域密度和一般梯度近似,研究了Si3P45个相的结构、电子和弹性性质.考虑的Si3P4结构包括分别具有空间群P63/ m, Fd-3 m, P-42 m,I M-3 M, P-43 m的β,γ,膺立方、立方和缺损立方相.总的能量计算表明,具有缺损闪锌矿... 详细信息

采用密度泛函理论的定域密度和一般梯度近似,研究了Si3P45个相的结构、电子和弹性性质.考虑的Si3P4结构包括分别具有空间群P63/ m, Fd-3 m, P-42 m,I M-3 M, P-43 m的β,γ,膺立方、立方和缺损立方相.总的能量计算表明,具有缺损闪锌矿结构的膺立方和缺损立方相相对于其它相能量最低,因而是最稳定的2个相.弹性常数计算表明,两个相对稳定的相有大的应变模量,因而结构上较硬.能带结构和分波态密度计算表明,在两种近似下,膺立方和缺损立方是半导体,而β,γ和立方相是金属.

关键词：磷化硅稳定性能带结构硬度

Reinforcement Learning algorithm for Solving Load Commitment Problem Considering a General Load Model

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Journal of Energy and Power Engineering 2013年第6期7卷 1150-1162页

作者： Thythodath Parambath Imthias ahamed Sayed Danish Maqbool Nazar Hussain Malik Department of Electrical Engineering King Saud University Riyadh 11421 Saudi Arabia

Under the smart grid paradigm, in the near future all consumers will be exposed to variable pricing schemes introduced by utilities. Hence, there is a need to develop algorithms which could be used by the consumers to schedule their loads. In this paper, load scheduling problem is formulated as a LCP （load commitment problem）. The load model is general and can model atomic and non-atomic loads. Furthermore, it can also take into consideration the relative discomfort caused by delay in scheduling any load. For this purpose, a single parameter ＂uric＂ is introduced in the load model which captures the relative discomfort caused by delay in scheduling a particular load. Guidelines for choosing this parameter are given. all the other parameters of the proposed load model can be easily specified by the consumer. The paper shows that the general LCP can be viewed as multi-stage decision making problem or a MDP （Markov decision problem）. RL （reinforcement learning） based algorithm is developed to solve this problem. The efficacy of the algorithm is investigated when the price of electricity is available in advance as well as for the case when it is random. The scalability of the approach is also investigated.

关键词： Reinforcement learning Markov decision problem demand response load scheduling problem load model.

Assessment of the Hydrochemical Characteristics of the Suez Gulf Coastal Waters during 2011-2013

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Journal of Environmental Protection 2016年第11期7卷 1497-1521页

作者： Ehssan M. Abo-El-Khair Laila M. Abdel Fattah ahamed M. Abdel-Halim Mohamed A. Abd-Elnaby Mamdouh A. Fahmy Hoda H. Ahdy ahamed Hemeilly ahamed Abu El-Soud Mohamed A. Shreadah Environmental Affairs Agency Ministry of Environmental Affairs Cairo Egypt National Institute of Oceanography and Fisheries Alexandria Egypt Environmental Affairs Agency Ministry of Environmental Affairs Cairo Egypt

The coastal region of the Suez Gulf, is one of the most densely industrialized zones in Egypt. In order to assess the quality of Suez Gulf coastal waters for the sustainable use and development, and consequently for the national income, 12 field campaigns were carried out in 3 years (2011-2013). The results of beach litter cleared out that the shoreline of the Suez Gulf, especially Ras Gharib area was subjected to many factors which undoubtedly affected the rate of man-made litter accumulation. The most abundant visible items were general litter as they represented 30.64% of the total items encountered. Oil, seaweeds as well as old and new tar constituted 15.41%, 14.85% and 11.84%, respectively. The increase on the levels of water temperature, Chl-a, TSM, DO, BOD, DOM, COD, ammonium ion, nitrite, nitrate, total phosphorus, silicate and total nitrogen developed a eutrophic region. In general, dissolved inorganic nitrogen (DIN) species were almost 9 times higher in the northern parts compared to the south-ern ones revealing that the northern parts of the Gulf were more affected by human impacts compared to the southern area. Moreover, concentrations of most studied metals such as Zn, Mn, Ni, Cu, Cr, Cd, Pb, and Hg were higher in Northern parts com-pared to southern parts of the Gulf. The concentrations of dissolved metals in the northern and southern Suez Gulf followed the following order: Fe ≥ Zn ≥ Cu > Pb > Mn > Ni > Cr > Cd ≥ Hg. Except for Hg, concentrations of metals were in the accepta-ble ranges recommended internationally. Hg concentrations especially in the northern Suez Gulf were slightly higher than the permissible levels. As the northern parts of the Gulf were more suffered from oil pollution, total petroleum hydrocarbons revealed higher concentrations in the northern parts compared to the southern parts of the Gulf. Seasonal variations, on the other hand, indicated higher levels of DO, BOD, DOM and COD, chloropyll-a, TSM, ammonia, nitrate, total nitrogen

关键词： Hydrography Nutrient Salts Heavy Metals Petroleum Hydrocarbons Coastal Water Suez Gulf

Optimization and production of antifungal hydrolysis enzymes by streptomyces aureofaciens against Colletotrichum gloeosporioides of mango

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Agricultural Sciences 2011年第2期2卷 146-157页

作者： Wafaa Mohamed Haggag Enas Mostafa Mohamed ahamed Mohamed El Azzazy Biotechnology and Genetic Engineering Unit National Research Center Cairo Egypt Department of Plant Pathology National Research Center Cairo Egypt

We isolated naturally occurring actinomycetes with an ability to produce metabolites having antifungal property against, Colletotrichum gloeosporioides, the causal agent of mango anthracnose. One promising strain was strong antifungal activity, was selected for further studies. Based on the physiological and biochemical characteristics, the bacterial strain was identical to Streptomyces aureofaciens. Culture filtrate collected from the exponential and stationary phases inhibited the growth of fungus tested, indicating that growth suppression was due to extracellular antifungal metabolites present in culture filtrate. Isolate highly produced extracellular chitinase and β-1,3-glucanase during the exponential and late exponential phases, respectively. In order to standardize the metabolite production some cultural conditions like different incubation time in hours, pH, carbon sources and concentrations and nitrogen source were determined. During fermentation, growth, pH and hydrolysis enzymes production were monitored .Treatment with bioactive components exhibited a significantly high protective activity against development of anthracnose disease on mango trees and increased fruit yield.

关键词： Antifungal Colletotrichum Gloeosporioides Mango Anthracnose and Streptomyces Aureofaciens.

Investigation the Risk of Spontaneous Combustion in Barapukuria Coal Mine, Dinajpur, Bangladesh

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Journal of Geoscience and Environment Protection 2016年第4期4卷 74-79页

作者： Sabbir ahamed Minhaj Uddin Monir Pradip Kumar Biswas Anwar Arfien Khan Department of Petroleum and Mining Engineering Jessore University of Science and Technology Jessore Bangladesh Institute of Mining Mineralogy and Metallurgy Bangladesh Council of Scientific and Industrial Research Joypurhat Bangladesh

Spontaneous combustion of coal is one of the major problems in the coal mine. The fire may occur due to exogenous and endogenous causes, by which coal liberated heat to the air or heat absorbed into it. It causes loss of production, as well as economical or financial losses and polluted the environment. If, the heat liberated during this process is allowed to accumulate, the rate of reaction increases exponentially and there is a further rise in temperature that generates the flame and produce CO, CO2, CH4, N2, O2 etc. In addition, the heat generated within coal affected by different factors such moisture, ash, volatile matter etc. of coal. This paper deals with the oxidation and spontaneous combustion risk in Barapukuria underground longwall coal mine, Dinajpur, Bangladesh. In this study, the laboratory analyses (proximate analyses) shows the inherent and the total moisture content value is average 2.73% and 5.82% to 12.75%, respectively. It indicates that these moisture contents are moderately liable to self heating. The less ash content value (av.13.2%) shows, it is less liable to spontaneous combustion. In addition to this, the temperature and concentration of some mine gases (CO, N2, O2) were monitored to calculate the Graham’s ratio. According to Graham’s ratio, the longwall faces have high oxidation risk and medium combustion risk. Therefore, the actual control of spontaneous combustion of coal is important to save coal mine from mine fires and also provides a real opportunity to improve the financial performance of the overall organization.

关键词： Spontaneous Combustion Proximate Analyses Underground Temperature Graham’s Ratio

Use of Renewable Energy Sources in Saudi Arabia through Smart Grid

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Journal of Energy and Power Engineering 2012年第7期6卷 1065-1070页

作者： Faisal R. Pazheri Nazar H. Malik Abdulrehman A. al-Arainy Safoora Ottukulotk Mohd F. Othman Essam A. AI-Ammar Imthias ahamed T. P. Electrical Engineering Department College of Engineering King Saud University Riyadh 11421 Saudi Arabia Centre for Artificial Intelligence & Robotics Faculty of Electrical Engineering Universiti Teknologi Malaysia Kuala Lumpur54100 Malaysia Electronics & Communication Engineering Department College of Engineering Thalassery Kannur 670107 Kerala India

Even though Saudi Arabia is the world＇s largest producer and exporter of petroleum and petroleum based products, it is also blessed with high potential of renewable energy sources like solar and wind. Untapped wind and solar energy sources, which are abundant throughout the kingdom, can be connected and optimally integrated into the grid through the use of smart grid technologies and the expansion of transmission facilities. Smart grid is an auto-balancing, self-monitoring power grid that accepts power from any source of fuel like oil, sun or wind and delivers electricity from suppliers to consumers. It helps to control the use of appliances in order to save energy, reduces cost and increase reliability. This paper describes the attributes of a smart grid and how these act as driving force to modernize the electrical power grid. The necessity of conservation of oil in Saudi Arabia is argued. Moreover, the vast availability of renewable energy sources like solar and wind in Saudi Arabia and advantages in utilizing these sources through smart grid technologies are advocated in this paper.

关键词： Solar energy wind energy smart grid conserving oil megawatt.