检索结果-南通市图书馆

Journal of Encapsulation and Adsorption Sciences 2011年第3期1卷 35-42页

作者： Zohra Dali-youcef Michèle Queneudec 不详

Activated mud has been employed to remove phenolic compounds, a common contaminant in wastewaters. Because of high surface area per unit area, activated mud is the most effective adsorbent and exhibits high capacity of adsorption of phenolic compounds. A complete study was undertaken on the adsorption of phenol starting from an aqueous solution on activated mud with ammonium chloride. The removal is found to be dependent on concentration of phenol and increasing of concentrations favour the uptake. The isotherms and kinetics of adsorption of phenol on activated mud were studied at 20oC. Equilibrium isotherm of phenol on activated mud is obtained and the results shows that the Langmuir model provided the best fit for the adsorption data. From the experimental results obtained, the adsorption process can be well described with the pseudo-second order model.

关键词： Activated Mud Adsorption Phenol Equilibrium Isotherm Contaminant

Effect of TiO_2 and ZrO_2 reinforcements on properties of Al_2O_3 coatings fabricated by thermal flame spraying

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Transactions of Nonferrous Metals Society of China 2016年第5期26卷 1345-1352页

作者： Rassim YOUNES Mohand Amokrane BRADAI Abdelhamid SADEDDINE youcef MOUADJI Ali BILEK Abderrahim BENABBAS Laboratory of Mechanics Materials and Energetic Faculty of Technology University of Bejaia Laboratory of Mechanics Faculty of Engineering Sciences Campus Chaabet-ErsasUniversity of Constantine Mechanical Laboratory of Structure and Energetic Mechanical Engineering DepartmentUniversity of Tizi-Ouzou Laboratory Processes for Materials Energy Water and Environment Faculty of Science and TechnologyUniversity of Bouira

The alumina composite coatings reinforced with 25% ZrO2 （denoted as AZ-25） and 3% TiO2 （denoted as AT-3） were deposited on low carbon steel using a thermal flame spraying. The microstructure, phase composition, microhardness and tribological properties of the coatings were investigated. The XRD results of the coatings reinforced by TiO2 （AT-3） revealed the presence of α-Al2O3 phase as matrix and new metastable phases of α-Al2O3 and α-Al2O3. However, the coatings reinforced by ZrO2 （AZ-25） consist of α-Al2O3 as matrix, q-ZrO2 and m-ZrO2. In most studied conditions, the AT-3 coating displays a better tribological performance, i.e., lower coefficient of frictions and wear rates, than the AZ-25 coating. It was also found that the microhardness of the coatings was decreased with the reinforcement of ZrO2 and increased with TiO2.

关键词： thermal spraying coatings reinforcements friction coefficient wear rate

Influence of heat treatment on microstructure and tribological properties of flame spraying Fe–Ni–Al alloy coating

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

Journal of Central South University 2018年第3期25卷 473-481页

作者： youcef Mouadji Mohand Amokrane Bradai Rassim Younes Abdelhamid Sad-eddine Abderrahim Benabbas National Polytechnic School of Constantine Department of Mechanical Engineering University of Constantine Laboratory of Mechanics Materials and Energetic Faculty of Technology University of Bejaia Laboratory Processes for Materials Energy Water and Environment Faculty of Science and TechnologyUniversity of Bouira

The Fe-based coatings in powder form were deposited on a steel type E335 by flame spraying *** effects of the post heat treatment on the microstructure and the mechanical properties of sprayed coatings were *** heat treatment was conducted in a furnace in air at 623 K,823 K and 1023 K for 1 h and then cooled in *** results showed that with the increase of annealing temperature,the microstructure of coating treated at 823 K and 1023 K had several changes as follows:the reduction of porosity,formation of carbides and *** was found that the solid solution FCC(Fe,Ni),intermetallic compound AlFe3 and carbides[Fe,C]were the main phases for coatings as-sprayed and treated at 623 K and while iron carbide,molybdenum carbide and oxide as Fe3O4 became the main phases and reinforced the solid solution FCC(Fe,Ni)phase for annealed coatings at 823 ***,it was observed the disappearance of molybdenum carbide and oxide Fe3O4 at 1023 *** coating annealed at 823 K exhibited an excellent wear resistance than the as-sprayed and annealed coatings at 623 K and 1023 K and shows the lower wear rate than another coating treated or as sprayed.

关键词： thermal spray coatings post heat treatment microstructure wear

The Impact of Religious Dimension on Entrepreneurial Intention by Using PLS Approach --Case Study

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

Economics World 2015年第3期3卷 137-144页

作者： Souar youcef Cherifi Djelloul Idrissi Mokhtar University Tahar Mouly of Saida Saida Algeria University Abou Bakr Belkaid of Tlemcen Saida Algeria University Mustapha Stambouli of Mascara Saida Algeria

In a complex environment resulted from the economic and technological changes, and the emergence of the uncertainty cases, the entrepreneurial thought knows a development in the determinants of entrepreneurial spirit, that has become a mechanism and a dynamic of the competitivety of international economies, starting by the construction of investment projects whether individual or collective, which are based on innovation and the use of technology as factors that have the ability to give business competitiveness and increase its economic efficiency, also that is through the creation of job opportunities and reaching the economic development. This research aims to study the effect of the religious dimension and the dimensions of entrepreneurial behavior on the entrepreneurial intention among youth who are interested in realizing entrepreneurial projects. The partial least squares approach （PLS） has been used in this study and it results that the religious dimension influences positively the entrepreneurial intention.

关键词： entrepreneurial behavior religious dimension entrepreneurial intention partial least squares approach (PLS)

Practical Model for Real Structure and Performance of Heavy Vehicles

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 Mechanics Engineering and Automation 2015年第2期5卷 68-75页

作者： Younes Abbassi youcef Ait-Amirat Rachid Outbib Department of Energy University of Technology of Belf ort-MontbOliard Belfort 90010 France Department of Energy University of Franche-Comte Belfort 90010 France LSIS (Laboratoire des Sciences de l 'Information et des Systkmes) University of Aix-Marseille Marseille 13397 France

In this paper, a new practical model for real heavy vehicle structure is developed to investigate dynamic responses under steering/acceleration or braking maneuvers. The generalized six DoFs （degrees-of-freedom） nonlinear vehicle model M1 including longitudinal, lateral, yaw, vertical, roll and pitch dynamics is validated using the measured data reported in different studies. This model takes the CG （center of gravity） of sprung mass, unsprung mass and total vehicle mass into account. Based on this model, the effects of the inertia parameters on the vehicle dynamic responses are investigated for more comprehensive assessments of the model structure. Another nonlinear vehicle model 342 derived from M1 which assumes that the vehicle has a single CG as reported in literature is also developed. The dynamic responses of the vehicle model Mj are compared with those of the model M2 to demonstrate the performance potential of the proposed nonlinear model. The results of dynamic responses with the nonlinear vehicle model MI suggest that the model could offer considerable potential in realizing enhanced ride and handling performance, as well as improved roll and pitch properties in a flexible manner.

关键词： Modeling nonlinear vehicle models inertial parameters heavy vehicle dynamics ride handling.

Synthesis and Characterization of N,N＇-bis（Salicylidene） Ethylenediamine： Study of Extractives Properties Versus the Copper （11） in Sulphate Medium

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 Environmental Science and Engineering(B) 2013年第7期2卷 442-447页

作者： Houria Sadou Tayeb Benabdallah Hasnia Reffas Mohamed Hadj youcef Department of Chemistry USTO (University of Sciences and Technology of Oran) Bir El Djir Oran Algeria

The synthesis and characterization of N,N＇-bis（salicylidene） ethylenediamine, Salen said that were carried out. The behavior of this ligand has been studied in solution in solvent homogeneous and heterogeneous systems in sulphate medium. The use of pH-metric titration, GRAN and JOB＇s methods have permitted the determination of different parameters governing the behavior of Salen in solution such as the acidity constant, the stability constant, the nature of the interaction solvent-solute, the solvation number, the stoichiometry of extracted complex etc.. Then the extraction of the Salen was finally undertaken to words the copper （II） sulfate medium. The pH of complexation, extraction time, the number of protons exchanged and the number of ligands have been finally determined.

关键词： Salen copper (II) metal complex acid-base behaviour liquide-liquide extraction.

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

当代中国青少年汉字使用状况研究报告

当代中国青少年汉字使用状况研究报告

作者： Mathieu Vincent youcef LASSED（马修）广东外语外贸大学

学位级别：硕士

中国语言文字工作委员会每年发布《中国语言生活状况报告》,投入大量的时间和精力来分析中国的语言状况并积极地探索提高国民语言能力的途径(在中小学校开展书法教育,改进文风,进行地方语言文字工作,语言规范化,构建语言和谐生活,大力... 详细信息

中国语言文字工作委员会每年发布《中国语言生活状况报告》,投入大量的时间和精力来分析中国的语言状况并积极地探索提高国民语言能力的途径(在中小学校开展书法教育,改进文风,进行地方语言文字工作,语言规范化,构建语言和谐生活,大力推广国家通用语言文字等等)。我想对此方面进行研究和评价来树立更敏锐的文化自觉,根据最新的专门文章和书本参考资料,中国网民的经验和感受来取得整体的了解。通过此论文的研究过程希望能够了解现代的中国社会。显而易见,更加深刻地理解中国年轻人关于汉字书写的状态问题给我提供一份宝贵的帮助。除此之外,我打算进一步知道中国人的汉字书写能力是否有所下降以及解密多媒体技术对这个问题的负面影响。长期用电脑打字,久而久之中国人的文字记忆受到很大的影响,所以我还想对目前的网络工具进行分析,探讨在多媒体环境下,在这个信息多元的时代里,中国少年人能否真正地保持平衡的语言生活。网络时代完全改变了中国传统的大众传播模式,很多网民成了语言的创造者,而且许多人往往会忘记汉字的书写方法,所以目前的语言使用跟以前截然不同。理所当然的是,我们应该尽量重视语言文字运用的实践。据我来说,练好汉字是一项需要长期付出的艰苦劳动。汉语在世界各地快速传播,增强国民的母语意识就是一件基本要务,也是国民的当务之急。

关键词：汉字学语言文字状况报告书写方法多媒体环境语言能力五笔字型传播模式手写汉字多媒体技术

Trace Metals in Sediments, Macroalgae and Benthic Species from the Western Part of Algerian Coast

同方学位论文库评论

在线全文

同方学位论文库

学校读者我要写书评

暂无评论

Journal of Environmental Science and Engineering 2011年第12期5卷 1604-1612页

作者： W. Benguedda N. Dali youcef R. Amara Department of Ecology and Environment University of Tlemcen Tlemcen 13000 Algeria Department of Biology University of Littoral-Opale Coast Wimereux 62930 France

The concentrations of Cd, Pb, Cu and Zn were measured in sediments and specimens of four marine organisms： green algae （Enteromorpha linza）, red algae （Corallina officinalis）, mollusc limpet （Patella ferruginea） and sea urchin （Paracentrotus lividus）. The samples were collected at four coastal stations located in two areas in the North-Western Algerian coast： Ghazaouet and Beni-saf. These areas are influenced by anthropogenic activities （harbour and industrial and urban wastes）. Metal concentrations measured in sediments and biota indicated that the area of Ghazaouet was the most polluted. We found high variability of metal bioaccumulation among the four species analysed. The highest concentrations were recorded in the algae whereas metal concentrations in sea urchin and limpet were more correlated with sediments metal concentrations.

关键词： Trace metals sediment marine algae benthic species Algeria.

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

辅助生殖技术的研究进展

广西医科大学学报 2005年第3期22卷 478-481页

作者：李慕军 youcef Khoudja Rabea 李柳铭广西医科大学第一附属医院生殖医学研究中心南宁530021

世界卫生组织80年代中末期在25个国家的33个研究中心组织了一次采用标准化诊断的不孕症夫妇的调查结果表明,发达国家约有5%～8%的夫妇受到不孕症的影响,发展中国家一些地区不孕症的患者发病率可高达30%.全世界的不孕症人数约为5 000～8 ... 详细信息

世界卫生组织80年代中末期在25个国家的33个研究中心组织了一次采用标准化诊断的不孕症夫妇的调查结果表明,发达国家约有5%～8%的夫妇受到不孕症的影响,发展中国家一些地区不孕症的患者发病率可高达30%.全世界的不孕症人数约为5 000～8 000万[1].据不完全统计,中国育龄夫妇中不孕症患者约占2%～6% ,目前还有增加的趋势.其中女性以输卵管因素为主,占40%～50%.男性以少精、阳萎、高密度畸形精子为常见因素[2].而传统的药物和手术治疗方法远不能满足患者对生育的需要.人类辅助生殖技术无疑是生物医学领域里的一场革命[3],解决了大多数不孕症患者通过其它治疗后仍不能受孕的问题.

关键词：辅助生殖技术手术治疗输卵管不孕症胚胎移植