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bandgap engineering to tune the optical properties of be_xMg_(1-x)X(X=S, Se, Te) alloys

Chinese Physics b 2018年第1期27卷 415-423页

作者： b Sabir N A Noor M Rashid Fasih ud Din Shahid M Ramay Asif Mahmood Centre for Advanced Studies in Physics Government College University Department of Physics School of Science University of Management and TechnologyLahore Pakistan Department of Physics COMSATS Institute of Information Technology Physics and Astronomy Department College of Science King Saud University Chemical Engineering Department College of Engineering King Saud University

Structural, electronic, and optical properties of alloys bexMgl-xX （X = S, Se, Te） in the assortment 0 〈 x 〈 1 were theoretically reported for the first time in zinc-blende （Zb） phase. The calculations were carried out by using full-potential linearized augmented plane wave plus local orbitals （FP-LAPW＋lo） formalism contained by the framework of density functional theory （DFT）. Wu--Cohen （WC） generalized gradient approximation （GGA）, based on optimization energy, has.been applied to calculate these theoretical results. In addition, we used becke and Johnson （mbJ-GGA） potential, modified form of GGA functional, to calculate electronic structural properties up to a high precision degree. The alloys were composed with the concentrations x = 0.25, 0.5, and 0.75 in pursuance of ＇special quasi-random structures＇（SQS） approach of Zunger for the restoration of disorder around the observed site of alloys in the first few shells. The structural parameters have been predicted by minimizing the total energy in correspondence of unit cell volume. Our alloys established direct band gap at different concentrations that make their importance in optically active materials. Furthermore, density of states was discussed in terms of the contribution of be and Mg s and chalcogen （S, Se, and Te） s and p states and observed charge density helped us to investigate the bonding nature. by taking into consideration of immense importance in optoelectronics of these materials, the complex dielectric function was calculated for incident photon energy in the range 0--15 eV.

关键词： bexMgl-xX (X = S Se Te) alloys zinc-blende (Zb) phase density functional theory (DFT),electronic and optical properties

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A one-step implicit iterative method for two finite families of asymptotically nonexpansive mappings in a hyperbolic space

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Applied Mathematics(A Journal of Chinese Universities) 2018年第3期33卷 274-286页

作者： Hafiz Fukhar-ud-din Amna Kalsoom Safeer H Khan Department of Mathematics and Statistics King Fahd University of Petroleum and Minerals Department of Mathematics and Statistics International Islamic University Department of Mathematics Statistics and Physics Qatar University

We introduce a one-step implicit iterative method for two finite families of asymptotically nonexpansive mappings in a hyperbolic space and use it to approximate common fixed points of these families. The results presented in this paper are new in the setting of hyperbolic spaces. On top, these are generalizations of several results in literature from banach spaces to hyperbolic spaces. At the end of the paper, we give an example to validate our results.

关键词： uniformly convex hyperbolic space asymptotically nonexpansive mapping common fixed point strong convergence

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Effect of inclusion on high cycle fatigue response of a powder metallurgy tool steel

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Journal of Central South University 2012年第7期19卷 1773-1779页

作者：姚君曲选辉 Rafi-ud-din 何新波章林 State Key Laboratory for Advanced Metals and Materials(University of Science and Technology beijing) School of Materials Science and Engineering University of Science and Technology Beijing

The high cycle fatigue response of a high V-alloyed powder metallurgy tool steel （AISI 11） with different inclusion sizes was studied. Two materials of this grade at a similar hardness of about HRC 60 were subjected to axial loading fatigue tests, tensile tests and fracture toughness measurements to investigate their mechanical properties. Large inclusion above 70 ~rn is indicated to be responsible for the tensile fracture which happens before yielding. The fatigue strength obtained up to 107 cycles is found to decrease from approximately 1 538 MPa to 1000 MPa with the inclusion size increasing above 30 Izm. The internally induced crack initiation is mainly attributed to the surface compressive residual stress of 300-450 MPa. Fractographic evaluation demonstrates that the crack initiation and propagation controlling factors of the two materials are almost the same, indicating that the two factors would be insignificantly affected by the inclusion size level. Paris sizes of the two materials both show a tendency to decrease as the ratio of stress intensity factor of crack origin to factor of fish-eye increases. The investigation into the relationship between stress intensity factors and fatigue life of the two materials further indicates that the high cycle fatigue behavior of AISI 11 is controlled by crack propagation.

关键词： powder metallurgy tool steel high cycle fatigue fractography fish-eye inclusion

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Context-Aware Collaborative Filtering Framework for Rating Prediction based on Novel Similarity Estimation

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Computers, Materials & Continua 2020年第5期63卷 1065-1078页

作者： Waqar Ali Salah ud Din Abdullah Aman Khan Saifullah Tumrani Xiaochen Wang Jie Shao School of Computer Science and Engineering University of Electronic Science and Technology of ChinaChengdu611731China Faculty of Information Technology The University of LahoreLahore54000Pakistan Sichuan Artificial Intelligence Research Institute Yibin644000China

Recommender systems are rapidly transforming the digital world into intelligent information *** valuable context information associated with the users’prior transactions has played a vital role in determining the user preferences for items or rating *** has.been a hot research topic in collaborative filtering-based recommender systems for the last two *** paper presents a novel Context based Rating Prediction(CbRP)model with a unique similarity scoring estimation *** proposed algorithm computes a context score for each candidate user to construct a similarity pool for the given subject user-item pair and intuitively choose the highly influential users to forecast the item *** context scoring strategy has an inherent capability to incorporate multiple conditional factors to filter down the most relevant *** with traditional similarity estimation methods,CbRP makes it possible for the full use of neighboring collaborators’choice on various *** conduct experiments on three publicly available datasets to evaluate our proposed method with random user-item pairs and got considerable improvement in prediction accuracy over the standard evaluation ***,we evaluate prediction accuracy for every user-item pair in the system and the results show that our proposed framework has outperformed existing methods.

关键词： Recommender system context-based similarity estimation rating prediction collaborative filtering

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Pattern of hepatitis C virus genotypes and subtypes circulating in war-stricken Khyber Pakhtunkhwa,Pakistan:Review of published literature

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Asian Pacific Journal of Tropical Medicine 2017年第11期10卷 1037-1042页

作者： Abdul Waheed Khan Sadia Nawab Zeeshan Nasim Abdul Haleem Khan Syed Ishfaq Ahmad Fazli Zahir Israr ud Din Institute of Information Sciences Academia SinicaTaiwan Center for biotechnology and Microbiology University of SwatPakistan Institute of biotechnology and Genetic Engineering The University of AgriculturePeshawarPakistan 4Department of ZoologyIslamia College PeshawarPakistan

Infection due to hepatitis C virus(HCV) is a major cause of fibrosis and hepatocellular carcinoma in Pakistan. In the current review, pattern of HCV genotypes and subtypes in Khyber Pakhtunkhwa province was ascertained in light of the available literature. After thorough analysis, genotype 3(58.27%) was determined to be the leading HCV genotype,followed by genotypes 2(12.39%), 1(9.54%) and 4(0.86%). The proportions of genotypes 5 and 6 were recorded as 0.09% and 0.22% respectively. Subtype wise, 3 a accounted for 48.67%, followed by subtype 2 a(10.91%), 3 b(9.43%), 1 a(5.84%), 1 b(3.66%), 2 b(1.45%) and genotype 4 with its undefined subtypes contributed a portion of0.86%. The cumulative share of subtypes 1 c, 2 c, 3 c, 5 a and 6 a was less than 1%. In11.51% cases, the subtype was untypeable while in 7.17% cases mixed subtypes were recorded. Gender wise, proportions of most HCV subtypes were marginally higher among males as compared to females. On the basis of studied groups, 3 a was pervasive among all groups except in intravenous drug users where 2 a was the major HCV ***, based on various geographical locations(provincial divisions), subtype 3 a revealed a ubiquitous distribution. Conclusively, HCV 3 a persists to be the principal subtype across the province of Khyber Pakhtunkhwa. The considerable number of untypeable subtypes in most studies urges for an improved genotyping system on the basis of local sequence data and practice of sequencing for determination of underlying subtype in untypeable cases. Further, studies on identification of subtypes transmission pattern are imperative for assessment of transmission origin and reinforcement of efficient control strategies. In addition, the current review emphasizes the need of attention toward HCV risk groups and ignored southern side of Khyber Pakhtunkhwa province for better holistic understanding of HCV genotype distribution pattern in the province.

关键词： Hepatitis C Hepatitis C virus Genotype Subtype

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Desulfovibrio desulfuricans aggravates atherosclerosis by enhancing intestinal permeability and endothelial TLR4/NF-kb pathway in Apoe^(-/-) mice

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Genes & Diseases 2023年第1期10卷 239-253页

作者： Kun Zhang Xian Qin Juhui Qiu Tong Sun Kai Qu Ahmad ud Din Wenhua Yan Tianhan Li Yidan Chen Wei Gu Xiancai Rao Guixue Wang Key Laboratory for biorheological Science and Technology of Ministry of Education State and Local Joint Engineering Laboratory for Vascular ImplantsCollege of BioengineeringChongqing UniversityChongqing 400044China College of Information and Management Sciences Henan Agricultural UniversityZhengzhouHenan 450046China School of Medicine Chongqing UniversityChongqing 400030China Department of Microbiology College of Basic Medical SciencesArmy Medical University(Third Military Medical University)Chongqing 400037China

It is increasingly aware that gut microbiota is closely associated with ***,which and how specific gut bacteria regulate the progression of atherosclerosis is still poorly *** this study,modified linear discriminant analysis was performed in comparing the gut microbiota structures of atherosclerotic and non-atherosclerotic mice,and Desulfovibrio desulfuricans(***)was found to be associatedwith ***-treated Apoe^(-/-) mice showed significantly aggravated *** proatherogenic effect of *** was attributed to its ability to increase intestinal permeability and subsequent raise in the transit of lipopolysaccharide(LPS)from the intestine to the *** LPS in the blood can elicit local and systemic inflammation and activate Toll-like receptor 4(TLR4)/nuclear factor-kb(NF-kb)signaling of endothelial ***-242,a specific inhibitor of TLR4,can ameliorate the development of *** atherosclerosis by blocking the LPS-induced activation of TLR4/NF-kb signaling.

关键词： Atherosclerosis Desulf ovibrio desulfuricans Gut microbiota Linear discriminant analysis TAK-242

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Growth and characterization of ZnO multipods on functional surfaces with different sizes and shapes of Ag particles

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Chinese Physics b 2013年第8期22卷 683-689页

作者： A Kamalianfar S A Halim Mahmoud Godarz Naseri M Navasery Fasih ud Din J A M Zahedi Kasra behzad K P Lim A Lavari Monghadam S K Chen Department of Physics Faculty of Science University Putra Malaysia43400 UPM Serdang Selangor Malaysia Department of Physics Farhangian UniversityIran Institute for Mathematical Research University Putra Malaysia43400 UPM Serdang Selangor Malaysia Department of Physics Faculty of Science Malayer UniversityMalayer Iran Department of Physics Karaj Branch Islamic Azad UniversityKaraj Iran Department of Physics Science Faculty Shahr-e-Ghods Branch Islamic Azad UniversityTehran Iran

Three-dimensional ZnO multipods are successfully synthesized on functional substrates using the vapor transport method in a quartz tube. The functional surfaces, which include two different distributions of Ag nanoparticles and a layer of commercial Ag nanowires, are coated onto silicon substrates before the growth of ZnO nanostructures. The structures and morphologies of the ZnO/Ag heterostructures are investigated using X-ray diffraction and field emission scanning electron microscopy. The sizes and shapes of the Ag particles affect the growth rates and initial nucleations of the ZnO structures, resulting in different numbers and shapes of multipods. They also influence the orientation and growth quality of the rods. The optical properties are studied by photoluminescence, UV-vis, and Raman spectroscopy. The results indicate that the surface plasmon resonance strongly depends on the sizes and shapes of the Ag particles.

关键词： ZnO ZnO-Ag surface plasmon resonance

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Efficient and cost-effective method to synthesize highly purified Ti_(4)AlN_(3) and Ti_(2)AlN

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Journal of Advanced Dielectrics 2019年第1期9卷 55-58页

作者： Muhammad Faraz ud Din Chenhui Yang Yi Tang* Yapeng Tian Yangyang Luo Yutao Wu Wenxiu Que Electronic Materials Research Laboratory Key Laboratory of the Ministry of Education and International Center for Dielectric Research and Shaanxi Engineering Research Center of Advanced Energy Materials and Devices School of Electronic and Information Engineering Xi’an Jiaotong UniversityXi’anShaanxi 710049P.R.China Hangzhou Joy Energy Technology Ltd Co. 83 Hongken Road Xiaoshan Economic Development Zone Hangzhou 311200ZhejiangP.R.China

Nitrides MAX have attracted ever-growing interest owing to its unique metallic and ceramic characteristics and ***,we report on the synthesis of highly purified Ti_(2)AlN and Ti_(4)AlN_(3) powders from Ti,Al and TiN powders by a facile atmosphere sintering *** obtained nitrides show highly pure phase and excellent layered *** for the composition difference of raw materials,both the nitrides can be sintered and obtained by same sintering temperature and holding time,which thus makes less processing time and less usage of synthesis parameters as compared to previously synthesis *** our knowledge,present work is one of the few reports on synthesis of Ti_(4)AlN_(3) and Ti_(2)AlN using atmosphere sintering ***,the lattice changes of the layered structure of Ti_(2)AlX(X/C=N)were studied by changing the composition of X position from the synthesis of Ti_(2)AlCN and Ti_(2)AlC,and the optimal formulation and synthesis mechanism of Ti_(4)AlN_(3) were also studied.

关键词： Ti_(4)AlN_(3) Ti_(2)AlN atmosphere sintering method nitrides MAX

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Few-layer Ti_(3)CN MXene for ultrafast photonics applications in visible band

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Journal of Materiomics 2023年第1期9卷 44-55页

作者： Zixin Yang Qi Yang Yulin Tian Xianghe Ren Chun Li Yuqian Zu Syed Zaheer ud Din Lingfeng Gao Jian Wu Hualong Chen Han Zhang Jie Liu Jingliang He Abdullah GAl-Sehemi International School for Optoelectronic Engineering Qilu University of Technology(Shandong Academy of Sciences)Jinan250353China College of Material Chemistry and Chemical EngineeringKey Laboratory of Organosilicon Chemistry and Material TechnologyMinistry of Edu-cationHangzhou Normal UniversityHangzhou311121China College of Advanced Interdisciplinary Studies National University of Defense TechnologyChangsha410073China Institute of Microscale Optoelectronics College of Physics and Optoelectronic EngineeringShenzhen UniversityShenzhen518060China Shandong Provincial Engineering and Technical Center of Light Manipulations and Shandong Provincial Key Laboratory of Optics and Photonic Device chool of Physics and ElectronicsShandong Normal UniversityJinan250358China State Key Laboratory of Crystal Materials Shandong UniversityJinan250100China Research Center for Advanced Materials Science(RCAMS) King Khalid UniversityAbha61413Saudi Arabia Department of Chemistry College of ScienceKing Khalid UniversityAbha61413Saudi Arabia

Ti_(3)CN,as a typical hetero-MXene,has attracted tremendous attention for its unique ***,its ultrafast photonics applications are still ***,the few-layer Ti_(3)CN MXene was successfully prepared by selective etching and molecular delamination *** nonlinear optical response of few-layer Ti_(3)CN MXene at 640 nm was studied using the open-aperture Z-scan *** asprepared Ti_(3)CN MXene sample exhibited excellent nonlinear saturable absorption characteristics,resulting in the nonlinear absorption coefficient b of4.05×10^(-2)cm/GW,which was one order of magnitude larger than that of black phosphorus(bP)and molybdenum disulfide(MoS_(2)).For the optical modulation applications of few-layer Ti_(3)CN MXene,passively Q-switched(PQS)solid-state visible lasers based on Ti_(3)CN saturable absorber(SA)at 522 nm,607 nm,639 nm,and 721 nm were successfully ***,a Ti_(3)CN-based stable passively mode-locked Pr:YLF red laser was also successfully achieved with a pulse duration of 30 ps,and the corresponding repetition rate was 73.1 *** optical modulation device based on few-layer Ti_(3)CN MXene shows good *** work demonstrates that the tremendous prospects of the few-layer Ti_(3)CN MXene as a visible optical modulation device in ultrafast photonics applications.

关键词： Ti_(3)CN MXene Z-scan Saturable absorber Optical modulator Pulsed visible lasers

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放电等离子烧结制备Mg2-xNdxNi(x=0～0.3)储氢合金

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北京科技大学学报 2011年第8期33卷 986-994页

作者：李平万琦 DIN Rafi-ud 谢东辉曲选辉北京科技大学材料科学与工程学院北京100083 北京北冶功能材料有限公司北京100192 北京市先进粉末冶金材料与技术重点实验室北京100083

采用放电等离子烧结(SPS)工艺制备了Mg2-xNdxNi(x=0,0.1,0.2,0.3)储氢合金.通过X射线衍射(XRD)和扫描电镜(SEM)研究了合金的相结构和表面形貌,利用等容压差法分析测试了合金的压力--组成--温度(PCT)曲线和吸放氢动力学性能,研究了烧结... 详细信息

采用放电等离子烧结(SPS)工艺制备了Mg2-xNdxNi(x=0,0.1,0.2,0.3)储氢合金.通过X射线衍射(XRD)和扫描电镜(SEM)研究了合金的相结构和表面形貌,利用等容压差法分析测试了合金的压力--组成--温度(PCT)曲线和吸放氢动力学性能,研究了烧结温度、稀土元素Nd对储氢合金微观组织结构和储氢性能的影响,比较了SPS技术与真空感应熔炼法制备的Mg基合金组织结构和储氢性能的异同.结果表明:SPS制备的Mg2-xNdxNi(x=0～0.3)系列储氢合金具有多相结构,储氢合金的吸放氢动力学性能良好;Nd元素有利于Mg合金化,不利于储氢量;烧结温度对储氢量、PCT曲线平台性能有明显影响;当Mg2-xNdxNi系合金中含有Mg和NdMg12相,PCT曲线出现双平台现象;与铸态合金相比,SPS制备的Mg1.7Nd0.3Ni储氢合金的吸放氢动力学性能较好,但储氢容量、放氢率和PCT曲线平台性能更差.

关键词：储氢合金镁合金放电等离子烧结(SPS) 储氢微观组织稀土

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