检索结果-南通市图书馆

Communications in Theoretical Physics 2015年第2期63卷 243-248页

作者： A.rafat m.m.rahman m.S.Alam A.A.mamun Department of Physics Jahangirnagar University

Electron-acoustic shock waves （EASWs） in an unmagnetized four-component plasma （containing hot elec- trons and positrons following the q-nonextensiv.e distribution, cold mobile viscous electron fluid, and immobile positive ions） are studied in nonplanar （cylindrical and spherical） geometry. With the help of the reductive perturbation method, the modified Burgers equation is derived. Analytically, the effects of nonplanar geometry, nonextensivity, relative number density and temperature ratios, and cold electron kinematic viscosity on the basic properties （viz. amplitude, width, speed, etc.） of EASWs are discussed. It is exarmined that the EASWs in nonplanar geometry significantly differ from those in planar geometry. The results of this investigation can be helpful in understanding the nonlinear features of EASWs in various astrophysical plasmas.

关键词： electron-acoustic shock waves electron-positron-ion plasmas modified Burgers equation nonpla-nar geometry nonextensivity

Hybrid Sensor Selection Technique for Lifetime Extension of Wireless Sensor Networks

在线全文

学校读者我要写书评

暂无评论

Computers, materials & Continua 2022年第3期70卷 4965-4985页

作者： Khaled m.Fouad Basma m.Hassan Omar m.Salim Information Systems Department Faculty of Computers and Artificial IntelligenceBenha UniversityBenha13518Egypt Faculty of Artificial Intelligence Kafrelsheikh UniversityKafrelsheikh33516Egypt Electrical Engineering Department Benha Faculty of EngineeringBenha UniversityBenha13518Egypt

Energy conservation is a crucial issue to extend the lifetime of wireless sensor networks(WSNs)where the battery capacity and energy sources are very *** energy-saving techniques can help designers overcome this issue by reducing the number of selected sensors that report environmental measurements by eliminating all replicated and unrelated *** paper suggests a Hybrid Sensor Selection(HSS)technique that combines filter-wrappermethod to acquire a rich-informational subset of sensors in a reasonable *** aims to increase the lifetime of WSNs by using the optimal number of *** the same time,HSS maintains the desired level of accuracy and manages sensor failures with the most suitable number of sensors without compromising the *** evaluation of the HSS technique has adopted four experiments by using four different *** experiments show that HSS can extend the WSNs lifetime and increase the accuracy using a sufficient number of sensors without affecting ***,to ensure HSS credibility and reliability,the proposed HSS technique has been compared to other corresponding methodologies and shows its superiority in energy conservation at premium accuracy measures.

关键词： Energy conservation WSNs intelligent techniques sensor selection

Effect of Fiber Loadings and Treatment on Dynamic mechanical, Thermal and Flammability Properties of Pineapple Leaf Fiber and Kenaf Phenolic Composites

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Journal of renewable materials 2018年第4期6卷 383-393页

作者： m.Asim m.Jawaid m.Nasir N.Saba Laboratory of Biocomposite Technology Institute of Tropical Forestry and Forest Products(INTROP)Universiti Putra Malaysia43400 SerdangSelangorMalaysia Department of Chemical Engineering College of EngineeringKing Saud UniversityRiyadhSaudi Arabia Composite Wood Forest Product DivisionForest Research Institute248006 DehradunIndia

This study deals with the analysis of dynamic mechanical,thermal and flammability properties of treated and untreated pineapple leaf fiber(PALF)and kenaf fiber(KF)phenolic *** indicated that storage modulus was decreased for all composites with increases in temperature and pattern of slopes for all composites,having almost the same values of E′at glass transition temperature(Tg).The peak of the loss modulus of pure phenolic composites was shown to be much *** the addition of kenaf/PALF,peaks were higher and shifted towards a high *** Tan delta peak height was low for pure phenolic composites and maximum for 60%PALF phenolic ***-Cole analysis was carried out to understand the phase behavior of the composite *** analysis(TGA)results indicated that pure phenolic composites have better thermal stability than PALF and kenaf phenolic *** and horizontal UL-94 tests were conducted and showed pure phenolic resin is highly fire *** overall results showed that treated KF composites enhanced the dynamic mechanical and thermal properties among all PALF/KF composites.

关键词： Pineapple leaf fiber kenaf fiber phenolic resin dynamic mechanical analysis thermogravimetric analysis flammability

Nutritional Profile of Children with major Sickle Cell Syndrome at the Centre of medical and Health Advice of Kipé, Conakry, 2018

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Case reports in Clinical medicine 2024年第3期13卷 73-84页

作者： mamadou Aliou Doukoure Ibrahima Sory Diallo m’mah Aminata Bangoura Amadou Oury Toure mamadou moustapha Diop Fatoumata Binta Diallo mohamed Sama Cherif Thierno Saidou Diallo Saidouba Cherif Camara Abdoulaye Toure Faculty of Health Science and Technology Gamal Abdel Nasser University Conakry Guinea National AIDS Control Programme Ministry of Health Gamal Abdel Nasser University Conakry Guinea

Introduction: Growth is a reflection of a child’s health and nutritional status. Children with sickle cell disease often have slower statural and weight development. The aim of this study was to evaluate the nutritional profile of children with sickle cell disease (SCD) registered in the CEmECO centre database. methodology: This was a cross-sectional study with simple random sampling of children aged 1 to 16 years registered in the clinic database. results: We collected information on 208 children, 121 of whom had sickle cell disease and 87 of whom were normal, with a sex ratio of 1.02. The mean age of the sickle cell patients was 8.7 ± 4.4 years, while that of the non-sickle cell patients was 9.5 ± 4 years. Haemoglobin electrophoresis revealed 103 homozygous (SS), 18 double heterozygous (SC, SBetaThal, SE) and 87 normal (AA) and/or sickle cell trait (AS) sickle cell cases. We observed a significant difference in the height/age ratio (P ¥). Conclusion: The results of our study revealed stunted growth in children with sickle cell disease.

关键词： Sickle Cell Disease Nutrition Growth Puberty Guinea

Light Curve Analysis and Period Study of Two Eclipsing Binaries UZ Lyr and Br Cyg

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

research in Astronomy and Astrophysics 2022年第2期22卷 135-142页

作者： K.Y.roobiat r.Pazhouhesh Department of Physics Faculty of SciencesUniversity of BirjandBirjandIran

Two eclipsing binary systems,UZ Lyr and Br Cyg,are semi-detached types whose secondary component fills its roche *** radial velocity and light curves of these systems have already been investigated separately,both their radial velocity and light curves are analyzed simultaneously for the first time in the present ***,the orbital period changes of these systems are *** results show that the mass transfers between components have negligible effects on the orbital period changes of these systems,but two light travel time effects are the reasons for the periodic behavior of the O-C curve for UZ *** could not remark more information about orbital period changes for Br Cyg,but we find a new orbital period for *** radial velocity and light curve analysis,we find a cold spot on the secondary component of Br *** new geometrical and physical parameters of both systems are obtained and their positions on the H-r diagram are demonstrated.

关键词： (stars:)binaries(including multiple):close (stars:)binaries:eclipsing stars:individual(UZ Lyr Br Cyg)

f(G,T) Gravity with Cylindrically Symmetric relativistic Fluids

在线全文

学校读者我要写书评

暂无评论

Communications in Theoretical Physics 2019年第2期71卷 220-230页

作者： m.Farasat Shamir m.Awais Sadiq Department of Sciences and Humanities National University of Computer and Emerging SciencesLahore CampusLahorePakistan

The aim of this paper is to examine the structure scalars with account of f(G, T) theory of gravity. We consider the cylindrically symmetric spacetime with dissipative anisotropic background. We have determined the structure scalars by orthogonally decomposing the riemann curvature tensor and it is shown that these scalars are associated with fundamental properties of fluid. We further investigate the mass function along with the transport equation and discuss their role on the evolutionary stages of relativistic stellar systems. We have also analyzed these structure scalars for static fluid distributions and it is concluded that all possible solutions of field equations can be expressed through these scalars.

关键词： f(G,T) gravity cylindrically symmetric spacetime structure scalars

Coexpression of receptor-tyrosine-kinases in gastric adenocarcinoma-a rationale for a molecular targeting strategy?

在线全文

学校读者我要写书评

暂无评论

World Journal of Gastroenterology 2007年第26期13卷 3605-3609页

作者： Daniel Drescher markus moehler Ines Gockel Kirsten Frerichs Annett müller Friedrich Dünschede Thomas Borschitz Stefan Biesterfeld martin Holtmann Thomas Wehler Andreas Teufel Kerstin Herzer Thomas Fischer martin r Berger Theodor Junginger Peter r Galle Carl C Schimanski Department of General and Abdominal Surgery Johannes Gutenberg University of Mainz MainzGermany First Department of Internal medicine Johannes Gutenberg University of Mainz MainzGermany Institute of Pathology Johannes Gutenberg University of MainzMainzGermany Third Department of Internal medicine Johannes Gutenberg University of Mainz MainzGermany Unit of toxicology and chemotherapy German Cancer Research CenterGermany

AIm： To define the （co-）expression pattern of target receptor-tyrosine-kinases （rTK） in human gastric adenocarcinoma. mETHODS： The （co-）expression pattern of VEGFr1-3, PDGFr（α/β and EGFr1 was analyzed by rT-PCr in 51 human gastric adenocarcinomas. In addition, IHC staining was applied for confirmation of expression and analysis of rTK localisation. rESULTS： The majority of samples revealed a VEGFr1 （98%）, VEGFr2 （80%）, VEGFr3 （67%）, PDGFrα （82%） and PDGFrβ （82%） expression, whereas only 62% exhibited an EGFr1 expression. 78% of cancers expressed at least four out of six rTKs. While VEGFr1-3 and PDGFrα revealed a predominantly cytoplasmatic staining in tumor cells, accompanied by an additional nuclear staining for VEGFr3, EGFr1 was almost exclusively detected on the membrane of tumor cells. PDGFrβ was restricted to stromal pericytes, which also depicted a PDGFrα expression. CONCLUSION： Our results reveal a high rate ofreceptor-tyrosine-kinases coexpression in gastric adenocarcinoma and might therefore encourage an application of multiple-target rTK-inhibitors within a combination therapy.

关键词： VEGFr EGFr PDGFr Cancer Adeno-carcinoma Gastric Stomach

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

考古植物遗存中的碳稳定同位素

东方考古

东方考古 2024年第1期 146-179页

作者： Juan Pedro Ferrio mònica Aguilera Jordi Voltas José Luis Araus 褚黎明阿拉贡研究与发展机构(ArAID) 阿拉贡农业研究与技术中心(CITA)森林资源部 CTFC-AGrOTECNIO联合研究单位莱里达大学农作物与森林科学系巴塞罗那大学生物学院植物生理学部综合作物生理生态学组农业技术研究中心(AGrOTECNIO) 山东大学文化遗产研究院

考古植物遗存是了解关于过去社会经历的社会和环境条件的宝贵信息来源。植物遗存巨大潜力的充分开发需要分析技术的应用。在这一背景下,考古植物遗存的碳稳定同位素组成或许能够提供关于环境条件、农业管理、食物网和饮食偏好等多方面... 详细信息

考古植物遗存是了解关于过去社会经历的社会和环境条件的宝贵信息来源。植物遗存巨大潜力的充分开发需要分析技术的应用。在这一背景下,考古植物遗存的碳稳定同位素组成或许能够提供关于环境条件、农业管理、食物网和饮食偏好等多方面的线索。本文全面介绍了分析植物遗存的碳稳定同位素在考古学中的潜在应用。在对决定植物碳稳定同位素特性的广泛生理和环境因素进行解释之后,对最相关的方法问题进行了讨论。其中,本文对样品的前处理方式、与大气变化有关的不确定性以及植物遗存在土壤中沉积前后经历的潜在变化进行了评述。以选定的案例研究为例,为碳稳定同位素在考古学中的应用提供了方法和概念上的线索。同时,也强调了依旧存在的挑战。

关键词：碳稳定同位素植物考古环境农业

moduli of Polarized Calabi–Yau Pairs

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Acta mathematica Sinica,English Series 2020年第6期36卷 631-637页

作者： János KOLLár Chen Yang XU Princeton University Princeton NJ 08544-1000USA mIT CambridgeMA 02139-4307USA

We prove that the irreducible components of the moduli space of polarized Calabi–Yau pairs are projective.

关键词： Polarized Calabi–Yau stable pairs moduli spaces

modeling of GPS SPS Timing Error using multilayered Neural Network

在线全文

学校读者我要写书评

暂无评论

Modeling of GPS SPS Timing Error using Multilayered Neural N...