检索结果-南通市图书馆

Dissolved gas analysis and dissipation factor measurement of mineral oil-based nanofluids under thermal and electrical faults

引用

High Voltage 2023年第3期8卷 455-465页

作者： Ahmed Maher Diaa-Eldin A.Mansour Khaled Helal ramadan A.A.Abd El Aal Department of Electrical Engineering Faculty of EngineeringPort-Said UniversityPort-SaidEgypt Department of Electrical Power Engineering Faculty of EngineeringEgypt-Japan University of Science and Technology(E-JUST)New Borg El-Arab CityAlexandriaEgypt Department of Electrical Power and Machines Engineering Faculty of EngineeringTanta UniversityTantaEgypt

Mineral oil is the most frequent insulating liquid used in oil-immersed transformers for electrical insulation and heat ***,oil-based nanofluids are becoming more popular in scientific research as they have proved to have better dielectric and thermal *** applying these nanofluids into actual transformers,they would be exposed to thermal and electrical ***,The aim of the authors is to investigate the generation pattern of dissolved gases in nanofluids under thermal and electrical faults and to assess the applicability of traditional Dissolved Gas Analysis(DGA)techniques if oil-based nanofluids are used in ***-based nanofluid samples were prepared using a magnetic stirrer and an ultrasonic homogeniser and then subjected to simulated thermal and electrical faults in the laboratory using properly sealed test *** types of metal oxides,Silicon dioxide,Titanium dioxide,and Aluminium oxide nanoparticles,have been used to prepare nanofluids with 0.02 g/L and 0.04 g/L *** gases released and dissolved into oil due to the simulated faults were analysed and compared to traditional mineral oil as a *** dielectric dissipation factor was obtained and analysed for all *** to the findings,the presence and concentration of nanoparticles were shown to influence the amount of gases *** a result,this research is crucial in guaranteeing that traditional DGA techniques can be employed in transformers that use oil-based nanofluids.

关键词： electrical thermal dioxide

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Impact of the source and serial passaging of goat mesenchymal stem cells on osteogenic differentiation potential:implications for bone tissue engineering

引用

Journal of Animal Science and Biotechnology 2016年第4期7卷 482-494页

作者： Hoda Elkhenany Lisa Amelse Marc Caldwell ramadan Abdelwahed Madhu Dhar Department of Large Animal Clinical Sciences University of Tennessee Department of Surgery Faculty of Veterinary MedicineAlexandria University

Background： Adult mesenchymal stem cells （MSCs） can be conveniently sampled from bone marrow, peripheral blood, muscle, adipose and connective tissue, harvested from various species, including, rodents, dogs, cats, horses, sheep, goats and human beings. The MSCs isolated from adult tissues vary in their morphological and functional properties. These variations are further complicated when cells are expanded by passaging in culture. These differences and changes in MSCs must be considered prior to their application in the clinic or in a basic research study. Goats are commonly used as animal models for bone tissue engineering to test the potential of stem cells for bone regeneration. As a result, goat MSCs isolated from bone marrow or adipose tissue should be evaluated using in vitro assays, prior to their application in a tissue engineering project. Results： In this study, we compared the stem cell properties of MSCs isolated from goat bone marrow and adipose tissue. We used quantitative and qualitative assays with a focus on osteogenesis, including, colony forming unit, rate of cell proliferation, tri-lineage differentiation and expression profiling of key signal transduction proteins to compare MSCs from low and high passages. Primary cultures generated from each source displayed the stem cell characteristics, with variations in their osteogenic potentials. Most importantly, low passaged bone marrow MSCs displayed a significantly higher and superior osteogenic potential, and hence, will be the preferred choice for bone tissue engineering in future in vivo experiments. In the bone marrow MSCs, this process is potentially mediated by the p38 MAPK pathway. On the other hand, osteogenic differentiation in the adipose tissue MSCs may involve the p44/42 MAPK pathway. Conclusions： Based on these data, we can conclude that bone marrow and fat-derived MSCs undergo osteogenesis via two distinct signaling pathways. Even though the bone marrow MSCs are the preferred source fo

关键词： Caprine mesenchymal Osteogenesis stem cells

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Solar thermochemical reactions Ⅱ:Synthesis of 2-aminothiophenes via Gewald reaction induced by solar thermal energy

引用

Chinese Chemical Letters 2008年第7期19卷 788-790页

作者： ramadan Ahmed Mekheimer Mohamed Abdallah Ameen Kamal Usef Sadek Chemistry Department Faculty of ScienceEl-Minia UniversityEl-Minia 61519Egypt

Green conditions have been developed for the synthesis of substituted 2-aminothiophenes employing multicomponent reactions of a ketone with active methylene nitrile and elemental sulphur induced by free solar thermal ... 详细信息

关键词： 2-Aminothiophenes Gewald reaction Solar thermal energy

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

An early discharge approach for managing hospital capacity

引用

International Journal of Modeling, Simulation, and Scientific Computing 2017年第1期8卷 83-95页

作者： Israa Mohamed Ibrahim El-Henawy ramadan Zean El-Din Department of Computing and Information Zagazig University 44519 ZagazigEgypt Institute of Statistical Studies and Research Cairo University 12613 GizaEgypt

The Kidney and Oncology Departments at Zagazig University Hospital are suffering from increased demand and limited *** patients who find all beds occupied are simply turned away,i.e.,no waiting is *** paper investigates the impact of an early discharge approach that can be applied to patients that have been scheduled to discharge within 5 h.A discrete event simulation(DES)model is built using empirical distributions based on real *** model has been validated against real data and the results have shown that the proposed early discharge approach can reduce the number of turned away patients by 10%in the Kidney Department,equivalent to 182 patients annually and by 11%in the Oncology Department,equivalent to 150 patients annually.

关键词： Simulation optimization discrete event simulation

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Some aspects affecting the response of RC compartment structures subjected to internal blast loads

引用

Earthquake Engineering and Engineering Vibration 2022年第1期21卷 135-148页

作者： Osman M.O.ramadan M.Galal El Sherbiny Ahmed M.Khalil Faculty of Engineering Cairo UniversityCairo 12411Egypt Higher Technological Institute(HTI)at 10th of ramadan City Sharqia 13658Egypt Structural Engineering and Construction Management Department Faculty of Engineering&TechnologyFutureUniversity in Egypt-FUECairo 16383Egypt

Protective compartments are typically used to protect some specific structures from internal explosions,such as industrial buildings that contain devices that may explode in certain *** research investigates how the response of reinforced concrete(RC)compartment structures subjected to internal blast loads are affected by the following aspects:introduction of material nonlinearity in the analysis,reinforcement ratio,and aspect ratio of the *** achieve this goal,a calibrated and sophisticated FE numerical model is introduced,and a parametric study for the intended aspects is carried out.A discussion of the results and conclusions are offered,which show the role of each aspect in the dynamic performance of the compartment *** main conclusions are as follows:introduction of material nonlinearity in this type of analysis and for these structures is very important and significant in obtaining accurate outputs that are similar to actual behavior;the reinforcement ratio has a significant effect on the response and its effect varies depending on the thickness of the compartment;in general,increasing the reinforcement ratio enhances the behavior and reduces the stresses in the compartment;and the aspect ratio of the compartment does not show a clear pattern on the response of such structures under internal blast loads.

关键词： blast loads protective structures nonlinear analysis explicit dynamic analysis

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Structural and Tectonic Evolution of El-Faiyum Depression,North Western Desert,Egypt Based on Analysis of Landsat ETM+,and SRTM Data

引用

Journal of Earth Science 2011年第1期22卷 75-100页

作者： Timothy M Kusky Talaat M ramadan Mahmoud M Hassaan Safwat Gabr Three Gorges Research Center for Geo-hazard State Key Laboratory of Geological Processes and Mineral Resources China University of Geosciences The Geological Applications and Mineral Resources Division National Authority for Remote Sensing and Space Sciences (NARSS) Cairo Egypt

False color Landsat ETM＋（bands 7, 4, 2 in RGB） and SRTM images of the EI-Faiyum depression, Egypt, highlights major NE-SW faults and other lineaments trending NW-SE and N-S. Airborne magnetic data reveal some E-W subsurface faults which are not recognized on Landsat ETM＋ and SRTM images. Ratio images （5/7, 3/1, 4/3） and （5/7, 5/1, 4） were used for lithological discrimination of different rock types. The EI-Faiyum area is occupied by sedimentary rocks of Middle Eocene, Upper Eocene, Oligocene, Lower Miocene, Pliocene, Pleistocene and Holocene. Understanding the structural regime of EI-Faiyum depression in the Western Desert of Egypt is significant in relation to the neotectonics of the Nile Delta and to the development of new communities west of the delta. The area is covered by Late Cretaceous, Middle to Late Eocene deposits, Oligocene deposits （comprising fluviatile sediments and basalt sheets） and Pliocene and Quaternary alluvium and sand deposits. New geological and structural maps were prepared at a scale of 1 ： 100 000 using Landsat ETM＋ and SRTM images coupled with extensive field work. The major structural trends are E-W, ENE, NS and NW--the same trends observed elsewhere in North Africa from NW Sudan to NE Egypt including north and central Sinai. EI-Faiyum depression is a structurally-controlled tectonic basin, marked by northeast-striking faults along its northern margin. These faults are parallel to similar faults of the Syrian arc fold belt, which includes a group of related faults, folds, push-up structures, and basins. Qarun Lake is located in the northern part of EI-Faiyum depression, at a right-step between two strands of the NE striking fault system. We have suggested elsewhere that EI-Faiyum depression is a pull-apart basin related to extension between these mismatched strands of strike-slip faults. The E-W structures are probably related to the relative motion between south Europe and north Egypt and closure of the Neotethys. The continuation of t

关键词： Egypt EI-Faiyum Syrian arc fold belt pull-apart basin Western Desert of Egypt.

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Patterns of liver profile disturbance in patients with COVID-19

引用

World Journal of Clinical Cases 2022年第7期10卷 2063-2071页

作者： Hend Ibrahim Shousha Ahmed ramadan Rania Lithy Mohamed El-Kassas Department of Endemic Medicine Faculty of MedicineCairo UniversityCairo 12556Egypt Department of Endemic Medicine Faculty of MedicineHelwan UniversityCairo 11795Egypt

Fever and cough are the most common clinical symptoms of coronavirus disease 2019(COVID-19),but complications(such as pneumonia,respiratory distress syndrome,and multiorgan failure)can occur in people with additional ***-19 may be a new cause of liver disease,as liver profile disturbance is one of the most common findings among *** molecular mechanism underlying this phenomenon,however,is still *** this paper,we review the most current research on the patterns of change in liver profile among patients with COVID-19,the possible explanation for these findings,and the relation to pre-existing liver disease in these patients.

关键词： Liver functions COVID-19 Liver profile Alanine transaminase aspartate transaminase Bilirubin

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Two cases of variant late infantile ceroid lipofuscinosis in Jordan

引用

World Journal of Clinical Cases 2019年第2期7卷 203-208页

作者： Omar Nafi Bashar ramadan Olaf Riess Rebecca Buchert Tawfiq Froukh Department of Pediatrics Faculty of Medicine Mutah University Institute of Medical Genetics and Applied Genomics Rare Disease Center University of Tübingen Department of Biotechnology and Genetic Engineering Philadelphia University

BACKGROUND Late infantile ceroid lipofuscinosis is a rare neurodegenerative disorder that appears between the ages of 2 and 4 years and is difficult to diagnose. In this report we present two sisters with this condition, and the clinical course consisted of delayed developmental skills initially and later regression of previously acquired skills. The cases were initially considered as childhood disintegrative disorder(CDD); however, when whole exome sequencing(WES) genetic testing was done, they proved to be variant late infantile ceroid lipofuscinosis. This is the first report from *** SUMMARY Clinical presentation included developmental delay and initially speech delay,followed by lose of sphincter control. Motor development was normal until 4 years of age, then they developed ataxia(fear of going downstairs) and weakness while walking. Atonic and myoclonic seizures become intractable, and this was followed by inability to stand or sit and loss of expressive language. In addition to complete blood count test, liver function test, kidney function test, serum electrolyte test, and blood sugar test, serum amino acid profile, B12 level test,thyroid function test, and a brain computed tomography scan were also *** electroencephalogram showed a generalized spike and wave pattern, and magnetic resonance imaging showed little to no abnormalities. After dealing with the cases as CDD, WES testing proved a final diagnosis of variant late infantile ceroid lipofuscinosis. Current treatment is anti-epileptic drugs and supportive care at home, and they are now in vegetative *** This report highlights the importance of WES for the identification of genetic diseases, especially neurodegenerative disorders.

关键词： Ceroid lipofuscinosis Childhood disintegrative disorder Lysosomal storage disorders Neurodegenerative disorders Variant late infantile Case report

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

FINITE GROUPS WHOSE MINIMAL SUBGROUPS ARE WEAKLY H-SUBGROUPS

引用

Acta Mathematica Scientia 2012年第6期32卷 2295-2301页

作者： M.M.Al-Mosa Al-Shomrani M.ramadan A.A.Heliel Department of Mathematics Faculty of Science 80203King Abdulaziz UniversityJeddah 21589Saudi Arabia Department of Mathematics Faculty of ScienceCairo UniversityGiza 12613Egypt Department of Mathematics Beni-Suef UniversityFaculty of Science 62511Beni-SuefEgypt

Let G be a finite group. A subgroup H of G is called an H-subgroup in G if NG（H）∩ H^g ≤ H for all g C G. A subgroup H of G is called a weakly H-subgroup in G if there exists a normal subgroup K of G such that G = HK and H N K is an H-subgroup in G. In this paper, we investigate the structure of the finite group G under the assumption that every subgroup of G of prime order or of order 4 is a weakly H-subgroup in G. Our results improve and generalize several recent results in the literature.

关键词： c-normal subgroup H-subgroup p-nilpotent group supersolvable group generalized Fitting subgroupi saturated formation

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Permutation-substitution image encryption scheme based on a modified chaotic map in transform domain

引用

Journal of Central South University 2017年第9期24卷 2049-2057页

作者： ramadan Noha Ahmed HossamEldin H El-khamy Said E Abd El-Samie Fathi E Faculty of Electronic Engineering Menofia University Faculty of Engineering Alexandria University

A new chaotic image encryption scheme based on permutation and substitution in the Fourier domain is *** Fourier Transform(FRFT)is used before the encryption scheme to get a large degree of *** permutation is achieved by Baker map and the substitution by a key-related-to-plain-image algorithm based on the modified Logistic *** of the Logistic map is developed to increase the space of the encryption key,and hence increase the *** key of the encryption algorithm dependents on the plain image,and thus,the cipher image is sensitive to both the initial key and the plain image to resist known-plaintext and chosen plaintext *** key space is large and hence the algorithm can effectively resist brute-force *** proposed scheme is examined using different performance evaluation metrics and the results prove that the proposed scheme is highly secure,and it can effectively resist different attacks.

关键词： Backer map chaotic encryption fractional Fourier transform (FRFT) modified Logistic map

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

欢迎您,

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

请选择保存的检索档案：

请选择收藏分类：

通借通还

欢迎您,

建议与咨询 留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

请选择保存的检索档案： 新增检索档案 确定 取消

请选择收藏分类： 新增自定义分类 确定 取消

通借通还

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

请选择保存的检索档案：

请选择收藏分类：