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Coupled Conductive-Convective-Radiative Heat Transfer in Hollow Blocks with Two Air Cells in the Vertical Direction Subjected to an Incident Solar Flux

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Fluid Dynamics & Materials Processing 2022年第5期18卷 1399-1407页

作者： Mourad Najjaoui Thami Ait-taleb Abdelhalim Abdelbaki Zaki Zrikem hassan chaib Polydiscilinary Faculty of Ouarzazate Ibn Zohr UniversityOuarzazateMorocco Faculty of Sciences Semlalia Cadi Ayyad UniversityMarrakeshMorocco

This work presents the results of a set of steady-state numerical simulations about heat transfer in hollow blocks in the presence of coupled natural convection,conduction and *** with two air cells deep in the vertical direction and three identical cavities in the horizontal direction are considered(typically used for building ceilings).Moreover,their outside horizontal surface is subjected to an incident solar flux and outdoor environment temperature while the inside surface is exposed to typical indoor environment *** flows are considered laminar and two-dimensional over the whole range of parameters *** conservation equations are solved by means of a finite difference method based on the control volumes approach,relying on the SIMPLE algorithm for what concerns the coupling of pressure and *** effects of the number of cells in the horizontal direction and the thermal conductivity on the heat transfer through the alveolar structure have been *** results show that the number of holes has a significant impact on the value of the overall heat flux through the considered structure.

关键词： Numerical simulation heat transfer coupled hollow concrete block control volumes approach

Opto-Structural Properties of Silicon Nitride Thin Films Deposited by ECR-PECVD

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World Journal of Condensed Matter Physics 2016年第1期6卷 7-16页

作者： Hicham Charifi Abdelilah Slaoui Jean Paul Stoquert hassan chaib Abdelkrim Hannour Laboratory of Condensed Matter Physics and Nanomaterials for Renewable Energy University Ibn Zohr Agadir Morocco ICube CNRS-Université de Strasbourg Strasbourg France Research Group Materials and Energy Polydisciplinary Faculty Ibn Zohr University Ouarzazate Morocco

Amorphous hydrogenated silicon nitride thin films a-SiNx:H (abbreviated later by SiNx) were deposited by Electron Cyclotron Resonance plasma enhanced chemical vapor deposition method (ECR-PECVD). By changing ratio of gas flow (R = NH3/SiH4) in the reactor chamber different stoichiometric layers x = [N]/[Si] ([N] and [Si] atomic concentrations) are successfully deposited. Part of the obtained films has subsequently undergone rapid thermal annealing RTA (800°C/1 s) using halogen lamps. Optical and structural characterizations are then achieved by spectroscopic ellipsometry (SE), ion beam analysis and infrared absorption techniques. The SE measurements show that the tuning character of their refractive index n(λ) with stoichiometry x and their non-absorption properties in the range of 250 - 850 nm expect for Si-rich SiNx films in the ultraviolet UV range. The stoichiometry x and its depth profile are determined by Rutherford backscattering spectrometry (RBS) while the hydrogen profile (atomic concentration) is determined by Elastic Recoil Detection Analysis (ERDA). Vibrational characteristics of the Si-N, Si-H and N-H chemical bonds in the silicon nitride matrix are investigated by infrared absorption. An atomic hydrogen fraction ranging from 12% to 22% uniformly distributed as evaluated by ERDA is depending inversely on the stoichiometry x ranging from 0.34 to 1.46 as evaluated by RBS for the studied SiNx films. The hydrogen loss after RTA process and its out-diffusion depend strongly on the chemical structure of the films and less on the initial hydrogen concentration. A large hydrogen loss was noted for non-thermally stable Si-rich SiNx films. Rich nitrogen films are less sensitive to rapid thermal process.

关键词： ECR-PECVD Silicon Nitride

Meso-Archean to Mid-Paleozoic Granitoids in Oulad Dlim Massif(the Pericratonic Terrane of the Reguibat Shield,West African Craton,Morocco):Petrology,Geochemistry,Geochronology and Geological Implications

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Journal of Earth Science 2022年第5期33卷 1152-1165页

作者： Haissen Faouziya Montero Pilar Molina Jose Francisco Lodeiro Francisco Mouttaqi Abdellah chaib Mustapha Bea Fernando LGAGE Département de GéologieFacultédes Sciences Ben M’sikHassan II University of CasablancaB.P.5366MaarifCasablancaMaroc Department of Mineralogy and Petrology University of GranadaCampus FuentenuevaGranada18002Spain Office National des Hydrocarbures et des Mines 5 Avenue Moulay HassanRabatMaroc

The Oulad Dlim Massif,adjacent to the Reguibat Shield in South Morocco was considered up to now as part of the Variscan belt(Mauritanides)with a polyphase geologic history and a complex geodynamic evolution implicating oceans closures and accretion of exotic terranes(Avalonian and Meguman)during the Variscan-Alleghanian *** use of modern technology to characterize the petrology,the geochemistry and the geochronology of the lithological units forming this region,combined to field surveys has led to an updated geological architecture and different geological *** Oulad Dlim Massif is mainly a deformed Archean terrane,as recorded by its eastern and western sectors,dominated in its central part by a bimodal felsic-mafic magmatism forming the Ediacaran *** study of these magmatic complexes supports strongly the intracontinental origin of this bimodal magmatism *** oceanic origin published before in *** exploration of this massif conducted also to the identification of a Silurian-Devonian sector in the western ***,up to date,different magmatic events lasting from the Meso-Archean to the Cretaceous are recorded in the Oulad Dlim Massif rocks,among them different generations of granitoids are *** data on granitoids from the Ediacaran sector are presented in this *** recent data demonstrates that Oulad Dlim Massif has been affected by the main Ediacaran–Cambrian extensional event widely documented in other structural domains of Morocco and other parts of North ***,the study of the Silurian-Devonian sector rocks highlighted the presence of a Caledonian tectonic event challenging the ideas about the paleogeography of this part of northwestern Africa and its geological evolution during the ***,despite the significant contribution of this extensive survey and the abundance of data on the Oulad Dlim Massif,more studies are required to reconstruct the puzzle at plate tectonic scale.

关键词： Archean Ediacaran bimodal magmatism extension intracontinental rifting Caledonian tectonic event petrology geochemistry

Review of experimental attempts of islet allotransplantation in rodents:Parameters involved and viability of the procedure

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World Journal of Gastroenterology 2014年第37期20卷 13512-13520页

作者： Leandro Ryuchi Iuamoto Alberto Meyer Eleazar chaib Luiz Augusto Carneiro D'Albuquerque Department of Gas-troenterology Liver and Pancreas Transplantation Surgery UnitUniversity of Sao Paulo

The purpose of the present study was to organize the parameters involved in experimental allotransplantation in rodents to elaborate the most suitable model to supply the scarcity of islet donors. We used the PubMed database to systematically search for published articles containing the keywords “rodent islet transplantation” to review. We included studies that involved allotransplantation experiments with rodents’ islets, and we reviewed the reference lists from the eligible publications that were retrieved. We excluded articles related to isotransplantation, autotransplantation and xenotransplantation, i.e., transplantation in other species. A total of 25 studies related to allotransplantation were selected for systematic review based on their relevance and updated data. Allotransplantation in rodents is promising and continues to develop. Survival rates of allografts have increased with the discovery of new immunosuppressive drugs and the use of different graft sites. These successes suggest that islet transplantation is a promising method to overcome the scarcity of islet donors and advance the treatment options for type 1 diabetes.

关键词： Islet transplantation Allograft Immunosuppression Type 1 diabetes Islet grafts Diabetes mellitus Islet Hyperglycemia

Spontaneous rupture of hepatic hemangiomas:A review of the literature

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World Journal of Hepatology 2010年第12期2卷 428-433页

作者： Marcelo AF Ribeiro Francine Papaiordanou Juliana M Gonalves Eleazar chaib Department of Surgery Medical SchoolUniversity of Santo Amaro Professor of Surgery at University Cidade de So Paulo Universidade Cidade de So Paulo Medical Student at Universidade Cidade de So Paulo Liver and Portal Hypertension Surgery Clinicas HospitalUniversity of So Paulo Medical School Nuffield Department of Surgery Churchill HospitalUniversity of Oxford

Hepatic hemangiomas are congenital vascular malformations,considered the most common benign mesenchymal hepatic tumors,composed of masses of blood vessels that are atypical or irregular in arrangement and size. Hepatic hemangiomas can be divided into two major groups:capillary hemangiomas and cavernous hemangiomas These tumors most frequently affect females (80%) and adults in their fourth and fifth decades of life. Most cases are asymptomatic although a few patients may present with a wide variety of clinical symptoms,with spontaneous or traumatic rupture being the most severe complication. In cases of spontaneous rupture,clinical manifestations consist of sudden abdominal pain,and anemia secondary to ahaemoperitoneum. Disseminated intravascular coagulopathy can also occur. Haemodynamic instability and signs of hypovolemic shock appear in about one third of cases. As the size of the hemangioma increases,so does the chance of rupture. Imaging studies used in the diagnosis of hepatic hemangiomas include ultrasonography,dynamic contrast-enchanced computed tomography scanning,magnetic resonance imaging,hepatic arteriography,digital subtraction angiography,and nuclear medicine studies. In most cases hepatic hemangiomas are asymptomatic and should be followed up by means of periodic radiological examination. Sur gery should be restricted to specific situations. Absolute indications for surgery are spontaneous or trau m atic rupture with hemoperitoneum,intratumoral blee ding and consumptive coagulopathy (Kassabach-Merrit syndrome). In a patient presenting with acute abdo minal pain due to unknown abdominal disease,sponta neous rupture of a hepatic tumor such as a hemangio ma should be considered as a rare differential diagnosis.

关键词： Hepatic hemangioma Giant hepatic hemangioma Liver tumor Spontaneous rupture Surgery

The DPGA for Conbining the Superscalar and Multithreaded Processors Principal

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High Technology Letters 2001年第1期7卷 79-85页

作者： Abdelkadel chaib, Hu Mingzeng (Department of Computer Science and Technology, Harbin Institute of Technology, Harbin 150001 P.R.China) Dept. of Computer Sci. and Technol. Harbin Institute of Technology Harbin 150001 China

The performance of scalable shared-memory multiprocessors suffers from three types of latency; memory latency, the latency caused by inter-process synchronization ,and the latency caused by instructions that take multiple cycles to produce results To tolerate these three types of latencies, The following techniques was proposed to couple: coarse-grained multithreading, the superscalar processor and a reconfigurable device, namely the overlapping long latency operations of one thread of computation with the execution of other threads The superscalar processor principle is used to tolerate instruction latency by issuing several instructions simultaneously The DPGA is coupled with this processor in order to improve the context-switching

关键词： DPGA Context switching Functional and control conflicts Data dependencies WAW RAW WAR hazards Tomasolo’s algorithm

Preparation and Properties of Poly （Substituted- Phenol-Formaldehyde） Prepolymer and His Ability to Remove Water Bacteria

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材料科学与工程（中英文A版） 2013年第12期3卷 843-852页

作者： Safia Miloudi Messaoud chaib Faculty of Science Exact Department of Chemistry B.P 78 Ibn-Khaldoun University Tiaret 14000 Algeria Department of Chemistry Faculty of Sciences Dr Moulay Taher University BP138 City Nasr Saida 20000 Algeria

单纤维和混杂纤维增强的马来酰亚胺基复合材料的制备与表征

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单纤维和混杂纤维增强的马来酰亚胺基复合材料的制备与表征

作者： chaib Mohammed 哈尔滨工业大学

学位级别：硕士

目前,许多合成纤维已经用作增强相,添加到基体树脂中。纤维增强复合材料的基体主要使用各种各样类型的树脂。但是,这些树脂具有许多缺点,例如固化过程中的体积收缩,对水、温度、高能射线的敏感性以及需要添加固化剂进行固化处理等。这... 详细信息

目前,许多合成纤维已经用作增强相,添加到基体树脂中。纤维增强复合材料的基体主要使用各种各样类型的树脂。但是,这些树脂具有许多缺点,例如固化过程中的体积收缩,对水、温度、高能射线的敏感性以及需要添加固化剂进行固化处理等。这限制了树脂基复合材料在各种领域中的使用。面对这些挑战,双马来酰亚胺树脂因其独特的性质,用作热固性树脂。首先,短碳纤维(SCFs)和短凯夫拉尔纤维(SKFs)分别用于增强双马来酰亚胺树脂。在固化之前,通过使用硅烷偶联剂对碳纤维进行化学处理,以增强纤维与树脂基体之间的相互作用,并改善其界面粘合性。通过傅立叶变换红外光谱(FT-IR)研究了该复合材料,研究结果表明在SCF和SKF的外表面均已观察到硅烷处理。我们注意到,SCF含量为30%的复合材料表现出最佳的机械性能,其弯曲强度和弯曲模量分别为174.8MPa和4.9GPa,拉伸强度和拉伸模量分别为105MPa,2.41 GPa,冲击强度为24.7 KJ/m。SKFs含量为30%的复合材料的弯曲强度、弯曲模量分别为155MPa,3.7GPa,拉伸强度和拉伸模量分别为96MPa,2.1GPa,冲击强度为18.7 KJ/m。其次,研究了混合短碳纤维和凯夫拉纤维短纤维增强双马来酰亚胺树脂的形态、结构、热学和机械性能。杂化纤维(SCFs)和(SKFs)用硅烷偶联剂进行表面处理,然后将各种杂化纤维含量合并到树脂基质中,然后使用压缩成型技术进行等温固化。该杂化材料具有出色的弯曲、拉伸和冲击性能。研究结果表明,杂化材料含量为15%的SCF和SKF含量为15%的杂化复合材料机械性能增强效果最好,弯曲强度、弯曲模量分别为192MPa和5.8GPa。抗拉强度和拉伸模量分别为145 MPa和2.60GPa,冲击强度为33.6 KJ/m。SEM和FTIR研究表明,增强混合纤维在双马来酰亚胺树脂基体内具有良好的分散性和粘合性。

关键词：双马来酰亚胺树脂短纤维短杂化纤维复合材料机械性能纤维增强复合材料

存储器替换机制及其实现用于PACT01:一个面向多线程的结合DPGA的新型处理器

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计算机工程与设计 2000年第6期21卷 24-27页

作者： A. chaib 胡铭曾哈尔滨工业大学计算机科学与技术系 150001

提出一种解决PACT01:一种结合动态可编程逻辑阵列(DPGA)的处理器的新型体系结制中cache的一致性与同步性问题的算法,并且解决多线程支持的快速上下文切换及快速用户级操作问题。存储器替换机制是解决cache的一致性问题及当cache未命中... 详细信息

提出一种解决PACT01:一种结合动态可编程逻辑阵列(DPGA)的处理器的新型体系结制中cache的一致性与同步性问题的算法,并且解决多线程支持的快速上下文切换及快速用户级操作问题。存储器替换机制是解决cache的一致性问题及当cache未命中时从局部或远程存储器到cache存储器的数据替换问题的一种硬件实现方法,产生冲突的原因是由于多线程并行的写入/读取的位置相同和读或写的位置相同。文中选择的是相联映射策略,同时也选择了最少最近使用LRU算法,即在cache未命中时替换最少最近使用的参考块,为实现LRU算法设置了与每块相对应的计数器。

关键词： DPGA 存储器替换机制多线程 PACT01 处理器