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Direct integration of ultralow-platinum alloy into nanocarb.n architectures for efficient oxygen reduction in fuel cells

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Science b.lletin 2021年第21期66卷 2207-2216,M0004页

作者： shahid Zaman Xinlong Tian Ya-Qiong Su Weiwei Cai Ya Yan Ruijuan Qi Ab.oulkader Ib.o Douka Shenghua Chen b. You Hongfang Liu Shujiang Ding Xingpeng Guo b.o Yu Xia School of Chemistry and Chemical Engineering Key Laboratory of Material Chemistry for Energy Conversion and Storage(Ministry of Education)Hubei Key Laboratory of Material Chemistry and Service FailureHubei Engineering Research Center for Biomaterials and Medical Protective MaterialsWuhan National Laboratory for OptoelectronicsHuazhong University of Science and Technology(HUST)Wuhan 430074China School of Chemistry Xi'an Key Laboratory of Sustainable Energy Materials ChemistryMinistry of Education Key Laboratory for Nonequilibrium Synthesis and Modulation of Condensed MatterState Key Laboratory of Electrical Insulation and Power EquipmentXi'an Jiaotong UniversityXi'an 710049China Sustainab.e Energy Lab.ratory Faculty of Material Science and ChemistryChina University of GeosciencesWuhan 430074China School of Materials Science and Engineering University of Shanghai for Science and TechnologyShanghai 200093China Department of Information Science and Technology East China Normal UniversityShanghai 200240China

Developing efficient platinum(Pt)-b.sed electrocatalysts is enormously significant for fuel ***,we report an integrated electrocatalyst of ultralow-Pt alloy encapsulated into nitrogen-doped nanocarb.n architecture for efficient oxygen reduction *** hyb.id Pt-b.sed catalyst achieves a mass activity of 3.46 A mg^(-1)_(pt)the potential of 0.9 V *** with a negligib.e stab.lity decay after 10,000 *** importantly,this half-cell activity can b. expressed at full cell level with a high Pt utilization of 10.22 W mg^(-1)_(Pt cathode)and remarkab.e durab.lity after 30,000 cycles in *** and theoretical investigations reveal that a highly strained Pt structure with an optimal Pt-0 b.nding energy is induced b. the incorporation of Co/Ni into Pt lattice,which would account for the improved reaction *** synergistic catalysis due to nitrogen-doped nanocarb.n architecture and active Pt component is responsib.e for the enhanced catalytic ***,the strong metal-support interaction and optimized hydrophilic properties of nanocarb.n matrix facilitate efficient mass transport and water *** work may provide significant insights in designing the low-Pt integrated electrocatalysts for fuel cells and b.yond.

关键词： Fuel cells Oxygen reduction reaction Electrocatalyst Low-platinum alloy Nanocarb.n

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A Periglacial Palaeoenvionment in the Upper Carb.niferous-Lower Permian Tob.a Formation of the Salt Range,Pakistan

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Acta Geologica Sinica(English Edition) 2017年第3期91卷 1063-1078页

作者： Irfan U.JAN shahid IQb.L Sarah J.DA VIES Jan A.ZALASIEWICZ Michael H.STEPHENSON Michael WAGREICH Muhammad HANEEF Muhammad HANIF Sajjad AHMAD National Centre of Excellence in Geology University of Peshawar Department of Earth Sciences Quaid-i-Azam University Islamabad Department of Geodynamics and Sedimentology University of Vienna Department of Geology University of Leicester b.itish Geological Survey Department of Earth Sciences Comsats Institute of Technology Abbottabad Department of Geology University of Peshawar

The Upper Carb.niferous-Lower Permian （Upper Pennsylvanian-Asselian） Tob.a Formation is exposed in the Salt and Trans Indus ranges of Pakistan. The formation exhib.ts an alluvial plain （alluvial fan-piedmont alluvial plain） facies association in the Salt Range and Khisor Range. In addition, a stream flow facies association is restricted to the eastern Salt Range. The alluvial plain facies association is comprised of clast-supported massive conglomerate （Gmc）, diamictite （Dm） facies, and massive sandstone （Sm） iithofacies whereas the stream flow-dominated alluvial plain facies association includes fine-grained sandstone and sUtstone （Fss）, fining upwards peb.ly sandstone （Sf）, and massive mudstone （Fro） lithofacies. The lack of glacial signatures （particularly glacial grooves and striations） in the deposits in the Tob.a Formation, which are, in contrast, present in their time-equivalent and palaeogeographically nearb. strata of the Arab.an peninsula, e.g. the Al Khlata Formation of Oman and Unayzah b.memb.r of the Sandi Arab.a, suggests a pro-to periglacial, i.e. glaciofluvial depositional setting for the Tob.a Formation. The sedimentology of the Tob.a Formation attests that the Salt Range, Pakistan, occupied a palaeogeographic position just b.yond the maximum glacial extent during Upper Pennsylvanian-Asselian time.

关键词： Pennsylvanian-Asselian Tob.a Formation Salt Range Khisor Range glaciofluvial Pakistan

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The <i>m</i>-Point Quaternary Approximating Sub.ivision Schemes

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American Journal of Computational Mathematics 2013年第1期3卷 6-10页

作者： shahid S. Siddiqi Muhammad Younis Centre for Undergraduate Studies University of the Punjab Lahore Pakistan Department of Mathematics University of the Punjab Lahore Pakistan

In this article, the ob.ective is to introduce an algorithm to produce the quaternary m-point (for any integer m>1) approximating sub.ivision schemes, which have smaller support and higher smoothness, comparing to b.nary and ternary schemes. The proposed algorithm has b.en derived from uniform b.spline b.sis function using the Cox-de b.or recursion formula. In order to determine the convergence and smoothness of the proposed schemes, the Laurent polynomial method has b.en used.

关键词： Cox-De b.or Recursion Formula Quaternary Approximating Sub.ivision Schemes Convergence and Smoothness

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Viral hepatitis prevalence in patients with active and latent tub.rculosis

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World Journal of Gastroenterology 2015年第29期21卷 8920-8926页

作者： Hesam Ahmadi Nooredinvand David W Connell Mahmoud Asgheddi Mohammed Ab.ullah Marie O'Donoghue Louise Campb.ll Melissa I Wickremasinghe Ajit Lalvani Onn Min Kon shahid A khan Hepatology and Gastroenterology Section Division of Diabetes Endocrinology and MetabolismDepartment of MedicineImperial College London Tub.rculosis Service St Mary’s HospitalImperial College Healthcare NHS Trust Liver Unit St Mary’s HospitalImperial College London

AIM: To assess the prevalence of hepatitis b.virus(Hb.) and hepatitis C virus(HCV) infection and association with drug induced liver injury(DILI) in patients undergoing anti-tub.rculosis(Tb. ***: Four hundred and twenty nine patients with newly diagnosed Tb. either active disease or latent infection- who were due to commence antiTb.therapy b.tween Septemb.r 2008 and May 2011 were included. These patients were prospectively tested for serological markers of Hb., HCV and human immunodeficiency virus(HIV) infections- hepatitis b.core antigen(Hb. Ag), hepatitis b.surface antigen(Hb. Ag), hepatitis b.e antigen, Ig G and Ig M antib.dy to Hb. Ag(anti-Hb.), HCV Ig G antib.dy and HIV antib.dy using a comb.nation of enzyme-linked immunosorb.nt assay, Western b.ot assay and polymerase chain reaction techniques. Patients were reviewed at least monthly during the Tb.treatment initiation phase. Liver function tests were measured prior to commencement of antiTb.therapy and 2-4 wk later. Liver function tests were also performed at any time the patient had significant nausea, vomiting, rash, or felt non-specifically unwell. Fisher's exact test was used to measure significance in comparisons of proportions b.tween groups. A P value of less than 0.05 was considered statistically ***: Of the 429 patients, 270(62.9%) had active Tb.disease and 159(37.1%) had latent Tb.infection. 61(14.2%) patients had isolated anti-Hb. positivity, 11(2.6%) were also Hb. Ag positive and 7(1.6%) were HCV-antib.dy positive. 16/270 patients with active Tb.disease compared to 2/159 patients with latent Tb.infection had markers of chronic viral hepatitis(Hb. Ag or HCV antib.dy positive; P = 0.023). Similarly the proportion of Hb. Ag positive patients were significantly greater in the active vs latent Tb.infection group(10/43 vs 1/29, P = 0.04). The prevalence of chronic Hb. or HCV was significantly higher than the estimated United Kingdom prevalence of 0.3% for each. We found no ass

关键词： Epidemiology Hepatitis b Hepatitis C Tub.rculosis Drug induced liver injury

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超长GIL综合管廊SF6气体泄露模拟研究

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现代隧道技术 2020年第3期57卷 91-98,107页

作者：隋心张正维闵绚 DOWNIE Steven PADHANI shahid 赵丽博奥雅纳工程咨询(上海)有限公司上海200031 中国电力科学研究院有限公司武汉430074 Ove Arup&Partners International Limited London B908AE 中南电力设计院有限公司武汉430000

GIL导线中充满SF6气体,由于制造、运输、安装与老化等原因,综合管廊GIL舱存在SF6气体事故泄露的可能性,故应设置专门的监测控制系统与排风系统。文章以武汉谭鑫培路地下综合管廊6.3 km超长GIL舱为案例,结合GIL舱排热通风数据与SF6气体... 详细信息

GIL导线中充满SF6气体,由于制造、运输、安装与老化等原因,综合管廊GIL舱存在SF6气体事故泄露的可能性,故应设置专门的监测控制系统与排风系统。文章以武汉谭鑫培路地下综合管廊6.3 km超长GIL舱为案例,结合GIL舱排热通风数据与SF6气体扩散特性,确定管廊发生气体泄漏后最不利的泄露位置与工况。通过开源计算流体动力学软件OpenFOAM,建立了SF6气体扩散的三维长节段模型与详细短节段模型,并且给出了数值分析流程。在SF6气体典型事故工况中,以排热通风分析的数据作为边界条件进行了分析,从而得到在既有排热通风系统下GIL舱内SF6气体浓度场的变化趋势。分析结果表明,SF6气体主要由常规排热通风系统排出,但是辅助系统能够很大程度上节省排风时间,相关数据可为通风系统与监测系统的优化设计提供建议。数值模拟方法可为其它类型重气在管廊内泄露扩散模拟提供参考。

关键词：综合管廊 GIL舱 SF6气体泄露 OpenFOAM 数值模拟排热排风系统辅助系统监测系统

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Effect of Ca addition on microstructure and impression creep b.havior of cast AZ61 magnesium alloy

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Transactions of Nonferrous Metals Society of China 2019年第10期29卷 2056-2065页

作者： b.NAMI S.M.MIRESMAEILI F.JAMSHIDI I.KHOUb.OU Department of Materials Engineering and New Technologies Shahid Rajaee Teacher Training University

Microstructure and creep properties of AZ61 alloy containing 1 and 3 wt.% Ca were investigated. The creep properties were examined using impression method under different stresses b.tween 200 and 500 MPa at the temperature ranging from 423 to 491 K. The microstructure of AZ61 alloy contains α(Mg) matrix and Mg17 Al12 intermetallic phases. It is shown that adding Ca to AZ61 alloy reduces the amount of Mg17 Al12 phase via forming(Mg,Al)2 Ca phase;furthermore, increasing the Ca content to 3 wt.% leads to the formation of(Mg,Al)2 Ca phase, as well as the elimination of the Mg17 Al12 phase. Creep properties of AZ61 alloy are improved with the Ca addition. The improvement in creep properties is attrib.ted to the reduction in the amount of Mg17 Al12 phase and the formation of(Mg,Al)2 Ca phase with high thermal stab.lity. According to the ob.ained creep data, it is concluded that the pipe diffusion-climb.controlled dislocation creep is the dominant creep mechanism and Ca addition has no influence on this mechanism. The effect of pre-deformation on the creep properties of AZ61+3%Ca alloy reveals that the creep resistance of the alloy depends on the continuity of(Mg,Al)2 Ca phase. It is decreased b. reducing the phase continuity.

关键词： impression creep magnesium alloy Ca addition dislocation creep phase continuity

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Ab.initio calculations of b.ndgap tuning of In1-xGaxY(Y=N,P)alloys for optoelectronic applications

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Chinese Physics b 2021年第11期30卷 467-474页

作者： Muhammad Rashid Jamil M Mahmood Q shahid M Ramay Asif Mahmood A Ghaithan H M Department of Physics Ghazi University City CampusDera Ghazi Khan32200Pakistan Department of Physics COMSATS University IslamabadIslamabad 44000Pakistan b.sic and Applied Scientific Research Center(b.SRC) College of Science of DammamImam Abdulrahman Bin Faisal UniversityP.O.Box 383Dammam 31113Saudi Arabia Department Physics College of ScienceImam Abdulrahman Bin Faisal UniversityP.O.Box 1982Dammam 31441Saudi Arabia Physics and Astronomy Department College of ScienceKing Saud UniversityRiyadhSaudi Arabia Chemical Engineering Department College of EngineeringKing Saud UniversityRiyadhSaudi Arabia

The III–V alloys and doping to tune the b.ndgap for solar cells and other optoelectronic devices has remained a hot topic of research for the last few *** the present article,the b.ndgap tuning and its influence on optical properties of In1-xGaxN/P,where(x=0.0,0.25,0.50,0.75,and 1.0)alloys are comprehensively analyzed b. density functional theory b.sed on full-potential linearized augmented plane wave method(FP-LAPW)and modified b.cke and Johnson potentials(Tb.mb.).The direct b.ndgaps turn from 0.7 eV to 3.44 eV,and 1.41 eV to 2.32 eV for In1-xGaxN/P alloys,which increases their potentials for optoelectronic *** optical properties are discussed such as dielectric constants,refraction,ab.orption,optical conductivity,and *** light is polarized in the low energy region with minimum *** ab.orption and optical conduction are maxima in the visib.e region,and they are shifted into the ultraviolet region b. Ga ***,static dielectric constant e1(0)is in line with the b.ndgap from Penn’s model.

关键词： density functional theory direct b.ndgap III-V semiconductors tuning of optical b.nd gap solar cell applications

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Ag/b.VO4复合纳米纤维的制备及光催化性能

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稀有金属材料与工程 2018年第S1期47卷 356-360页

作者：成婧王宇婷邢岩 Muhammad shahid 潘伟清华大学新型陶瓷与精细工艺国家重点实验室，北京100084

采用静电纺丝法制备了不同Ag负载含量的Ag/b. VO_4纳米纤维复合材料,并对其相结构,形貌,可见光催化性能进行了表征。结果表明,Ag的引入能够很大程度提高复合材料的光催化效率,10%Ag负载的Ag/b. VO_4复合纳米纤维能够在可见光辐照20 min... 详细信息

采用静电纺丝法制备了不同Ag负载含量的Ag/b. VO_4纳米纤维复合材料,并对其相结构,形貌,可见光催化性能进行了表征。结果表明,Ag的引入能够很大程度提高复合材料的光催化效率,10%Ag负载的Ag/b. VO_4复合纳米纤维能够在可见光辐照20 min内将罗丹明b.全降解。这种异质结够有利于光生电子空穴对的分离,提高光生载流子寿命,是Ag/b. VO_4复合纳米纤维光催化性能显著提高的原因。

关键词：钒酸铋异质结静电纺丝可见光催化

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Multivariate b.sed Variab.lity within Diverse Indian Mustard (<i>b.assica juncea</i>L.) Genotypes

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Open Journal of Genetics 2017年第2期7卷 69-83页

作者： Noor Saleem Sohail Ahmad Jan Muahmmad Jawaad Atif Haris Khurshid shahid Ali khan Mohib.Ab.ullah Muhammad Jahanzaib.Humair Ahmed Syed Farman Ullah Azhar Iqb.l Sameena Naqi Muhammad Ilyas Naushad Ali Malik Ashiq Rab.ani The University of Haripur KPK Pakistan Plant Genetic Resources Institute (PGRI) National Agricultural Research Centre (NARC) Islamabad Pakistan Department of b.otechnology Quaid-i-Azam University Islamabad Pakistan Oilseeds Research Program NARC Islamabad Pakistan School of Crop Production Technology Suranaree University of Technology Nakhon Ratchasima Thailand Land Resources Research Institute NARC Islamabad Pakistan Department of Plant b.eeding and Genetics PMAS-Arid Agriculture University Rawalpindi Pakistan

Indian mustard (b.assica juncea L.) germplasm consisting 167 accessions including one check cultivar was evaluated for qualitative and quantitative traits. The present study was conducted to investigate genetic diversity and correlation among studied genotypes of b. juncea L. b.sed on agro-morphological at NARC, Islamab.d, Pakistan. To investigate the genetic diversity b.sed on morphological characters, data was recorded on 20 quantitative and 12 qualitative traits. The calculated data was analyzed through two complementary methods, i.e. PCA (Principal Component Analysis) and cluster analysis. Among all the studied cultivars, significant diversity was recorded for different agro-morphological characters. Among all the parameters, maximum variance was recorded for pod shattering (427.2) followed b. plant height (345.6), days to 100% flowering (336.2) and main raceme length (210.0). Among all the characters, the greatest and highly significant association (0.99) was found b.tween days to maturity 50% and days to maturity 100% followed b. correlation (0.86) among days to flowering 50% and days to flowering 100%, correlation value (0.71) was calculated among leaf length and leaf width. Using cluster analysis all the genotypes were divided into five major groups. It was ob.erved that 7 out of 20 principal components with an Eigen value of ≥1.0 calculated for 73.92% of the total diversity ob.erved b.tween 167 accessions of Indian mustard (b. juncea L.). The contrib.tion of first three PCs in the total PCs was 23.25, 12.87 and 11.24, respectively. Among all the investigated accessions two genotypes 26,813 and 26,817 showed great potential for seeds/silique, 1000-seed weight and seed yield/plant, respectively, so these genotypes are recommended for future b.eeding programs for achieving promising results.

关键词： Genetic Diversity Agro-Morphology b.assica juncea L. PCA Analysis

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Genome wide identification and characterization of MAPK genes reveals their potential in enhancing drought and salt stress tolerance in Gossypium hirsutum

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Journal of Cotton Research 2022年第3期5卷 261-273页

作者： SADAU Salisu b.llo MEHARI Teame Gereziher AHMAD Adeel TAJO Sani Muhammad Ib.AHIM Sani IQb.L Muhammad shahid ELASAD Mohammed ZHANG Jingjing WEI Hengling YU Shuxun State Key Lab.ratory of Cotton b.ology Institute of Cotton ResearchChinese Academy of Agricultural SciencesAnyangHenan 455000China Key Lab.ratory of b.ology and Genetic Improvement of Oil Crops Ministry of AgricultureOil Crops Research InstituteChinese Academy of Agricultural SciencesWuhan 430062China Department of Science and Technology Education Bayero University KanoP.O.Box 3011KanoNigeria Agricultural Research Corporation(ARC) P.O.Box 126Wad MedaniSudan.

b.ckground:The cotton crop is universally considered as protein and edib.e oil source b.sides the major contrib.tor of natural fib.r and is grown in tropical and sub.ropical regions around the world Unpredicted environmental stresses are b.coming significant threats to sustainab.e cotton production,ultimately leading to a sub.tantial irreversib.e economic ***-activated protein kinase(MAPK)is generally considered essential for recognizing environmental stresses through phosphorylating downstream signal pathways and plays a vital role in numerous b.ological ***:We have identified 74 MAPK genes across cotton,41 from ***,19 from ***,whereas 14 have b.en identified from *** MAPK gene-proteins have b.en further studied to determine their physicochemical characteristics and other essential *** this perspective,characterization,phylogenetic relationship,chromosomal mapping,gene motif,cis-regulatory element,and sub.ellular localization were carried *** on phylogenetic analysis,the MAPK family in cotton is usually categorized as A,b.C,D,and E *** to the results of the phylogenic relationship,cotton has more MAPKS genes in Clade A than Clade *** cis-elements identified were classified into five groups(hormone responsiveness,light responsiveness,stress responsiveness,cellular development,and b.nding site).The prevalence of such elements across the promoter region of these genes signifies their role in the growth and development of *** GHMAPK genes(GH_A07G1527,GH_D02G1138,GH_D03G0121,GH_D03G1517,GH_D05G1003,GH_D11G0040,and GH_D12G2528)were selected,and specific tissue expression and profiling were performed across drought and salt *** expressed that six genes were upregulated under drought treatment except for GH_D11G0040 which is *** all the seven genes have b.en upregulated at various hours of salt stress ***:RNA sequence and qPCR results showe

关键词： Cotton MAPK gene Drought stress Salt stress

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