检索结果-南通市图书馆

Journal of Semiconductors 2014年第7期35卷 1-9页

作者： muhammad Bilal m.shafiq Iftikhar Ahmad Imad Khan Department of Physics University of MalakandChakdaraPakistan

Structural, elastic, electronic and optical properties ofzinc-chalcogenides （viz. ZnX, X = S, Se and Te） are studied in zinc-blende structure under hydrostatic pressure using the full-potential linearized augmented plane wave method. Generalized gradient approximation is used for exchange correlation potentials. Pressure-dependent lattice constants and bulk moduli are obtained using the optimization method. Young＇s modulus, Poisson＇s ratio, internal strain parameter and anisotropy are also calculated. The higher values of Young＇s modulus in comparison to the bulk modulus show that these materials are hard to break. Poisson＇s ratio is computed for the first time for these materials to the best of our knowledge and its values show higher ionic contribution in these materials. modified Becke and Johnson （mBJ） method is used to study band gaps, density of states, dielectric function and refractive index. Electronic study shows direct band gaps convert to indirect band gaps with increasing pressure in the case of ZnS and ZnTe. We compared our results with other theoretical and experimental results. Our results are far better than other theoretical results because mBJ is the best technique to treat Ⅱ-Ⅵ semiconductors.

关键词： semiconductors elastic properties electronic band structures

在线全文

学校读者我要写书评

暂无评论

Journal of Rare Earths 2018年第10期36卷 1106-1111页

作者： Sardar Ahmad m.shafiq Rashid Ahmad S.Jalali-Asadabadi Iftikhar Ahmad Department of Chemistry University of Malakand Center for Computational materials Science University of Malakand Department of Physics Abbottabad University of Science and Technology Department of Physics Faculty of SciencesUniversity of Isfahan

In this paper, we explored the structural, elastic and mechanical properties of the strongly correlated electron systems, intermetallic Ln-Au（Ln = Ce, Pr, Nd, Gd, Tb, Dy, Ho, Er, Tm, Yb, Lu） in cubic structure,using PF-LAPW method within the density functional theory. Structural properties of these intermetallics were investigated by treating the exchange-correlation potential with the GGA-PBE, GGA-PBEsol and GGA ＋ U. The effectiveness of the U for the structural properties as compared to other methods confirms the strong correlated nature of these compounds and the calculated lattice constants endorse the divalency of Yb. The results demonstrate the stable cubic CsCl structure of these compounds. Bulk modulus, Young＇s modulus, shear modulus, B/G ratio, Cauchy pressure, Poisson＇s ratio, anisotropic ratio,Kleinman parameters and Lame＇s coefficients were studied using the PBEsol to evaluate their importance in various types of engineering applications. The most prominent features of these compounds are their ductility, very high melting points, resistance to corrosion, and anisotropic nature.

关键词： Strongly correlated electron systems Rare-earth monoaurides mechanical properties Ab-initio calculation

Pulsed ion beam-assisted carburizing of titanium in methane discharge

在线全文

学校读者我要写书评

暂无评论

Chinese Physics B 2010年第1期19卷 247-256页

作者： m.shafiq m.Hassan K.Shahzad A.Qayyum S.Ahmad R.S.Rawat m.Zakaullah Department of Physics Quaid-i-Azam University Department of Physics GC University National Tokamak Fusion Program Natural Sciences and Science Education National Institute of EducationNanyang Technological University

The carburizing of titanium （Ti） is accomplished by utilizing energetic ion pulses of a 1.5 kJ mather type dense plasma focus （DPF） device operated in methane discharge. X-ray diffraction （XRD） analysis confirms the deposition of polycrystalline titanium carbide （TIC）. The samples carburized at lower axial and angular positions show an improved texture for a typical （200）TIC plane. The Williamson-Hall method is employed to estimate average crystallite size and microstrains in the carburized Ti surface. Crystallite size is found to vary from - 50 to 100 nm, depending on the deposition parameters. microstrains vary with the sample position and hence ion flux, and are converted from tensile to compressive by increasing the flux. The carburizing of Ti is confirmed by two major doublets extending from 300 to 390 cm^-1 and from 560 to 620 cm^-1 corresponding to acoustic and optical active modes in Raman spectra, respectively. Analyses by scanning electron microscopy/energy dispersive x-ray spectroscopy （SEm/EDS） have provided qualitative and quantitative profiles of the carburized surface. The Vickers microhardness of Ti is significantly improved after carburizing.

关键词： carbide plasma focus microstructure surface morphology

Investigation of 50 Hz Pulsed DC Nitrogen Plasma with Active Screen Cage by Trace Rare Gas Optical Emission Spectroscopy

在线全文

学校读者我要写书评

暂无评论

Plasma Science and Technology 2014年第4期16卷 324-328页

作者： A.SAEED A.W.KHAN m.shafiq F.JAN m.ABRAR m.ZAKA-UL-ISLAm m.ZAKAULLAH Department of Physics Gomal University Department of Physics Quaid-i-Azam University Department of Physics Hazara University Mansehra Plasmant Department of Chemistry Univesity of Antwerp campus DriEkin

Optical emission spectroscopy is used to investigate the nitrogen-hydrogen with trace rare gas （4% Ar） plasma generated by 50 Hz pulsed DC discharges. The filling pressure varies from 1 mbar to 5 mbar and the current density ranges from 1 mA-cm-2 to 4 ***-2. The hydrogen concentration in the mixture plasma varies from 0% to 80%, with the objective of identifying the optimum pressure, current density and hydrogen concentration for active species （[N] and IN2]） generation. It is observed that in an N2-H2 gas mixture, the concentration of N atom density decreases with filling pressure and increases with current density, with other parameters of the discharge kept unchanged. The maximum concentrations of active species were found for 40% H2 in the mixture at 3 mbar pressure and current density of 4 ***-2.

关键词： TRG-OES DC glow discharge reactive species

Nitriding molybdenum: Effects of duration and fill gas pressure when using 100-Hz pulse DC discharge technique

在线全文

学校读者我要写书评

暂无评论

Chinese Physics B 2014年第10期23卷 349-356页

作者： U.Ikhlaq R.Ahmad m.shafiq S.Saleem m.S.Shah T.Hussain I.A.Khan K.Abbas m.S.Abbas Department of Physics Government College University Centre for Advanced Studies in Physics (CASP) Government College University Department of Physics Quaid-i-Azam University Department of Physics GC University Faisalabad

molybdenum is nitrided by a 100-Hz pulsed DC glow discharge technique for various time durations and fill gas pressures to study the effects on the surface properties of molybdenum. X-ray diffractometry （XRD）, scanning electron microscopy （SEm）, and atomic force microscopy （AFm） are used for the structural and morphological analysis of the nitrided layers. Vickers＇ microhardness tester is utilized to investigate surface microhardness. Phase analysis shows the formation of more molybdenum nitride molecules for longer nitriding durations at fill gas pressures of 2 mbar and 3 mbar （1 bar = 105 Pa）. A considerable increase in surface microhardness （approximately by a factor of 2） is observed for longer duration （10 h） and 2-mbar pressure. Longer duration （10 h） and 2-mbar fill gas pressure favors the formation of homogeneous, smooth, hard layers by the incorporation of more nitrogen.

关键词： pulsed DC glow discharge scanning electron microscopy atomic force microscopy microhard-ness

methacrylated gelatin and platelet-rich plasma based hydrogels promote regeneration of critical-sized bone defects

在线全文

学校读者我要写书评

暂无评论

Regenerative Biomaterials 2024年第4期3卷 66-81页

作者： Shichao Lian Zhiyu mu Zhengchao Yuan muhammad shafiq Xiumei mo Weidong mu Department of Traumatic Orthopaedics Shandong Provincial HospitalShandong UniversityJinanShandong 250012China Zoucheng People’s Hospital ZouchengShandong 273500China Department of medical Physics and Biomedical Engineering University of LondonLondon WC1E 6BTUK State Key Laboratory for modification of Chemical Fibers and Polymer materials Shanghai Engineering Research Center of Nano-Biomaterials and Regenerative MedicineCollege of Biological Science and Medical EngineeringDonghua UniversityShanghai 201620PR China Innovation Center of Nanomedicine(iCONm) Kawasaki Institute of Industrial PromotionKawasaki-KuKawasaki 210-0821Japan

Physiological repair of large-sized bone defects requires instructive scaffolds with appropriate mechanical properties,biocompatibility,biodegradability,vasculogenic ability and *** objective of this study was to fabricate in situ injectable hydrogels using platelet-rich plasma(PRP)-loaded gelatin methacrylate(Gm)and employ them for the regeneration of large-sized bone *** performed various biological assays as well as assessed the mechanical properties of Gm@PRP hydrogels alongside evaluating the release kinetics of growth factors(GFs)from *** Gm@PRP hydrogels manifested sufficient mechanical properties to support the filling of the tissue *** biofunction assay,the Gm@PRP hydrogels significantly improved cell migration and ***,transcriptome RNA sequencing of human umbilical vein endothelial cells and bone marrow-derived stem cells were performed to delineate vascularization and biomineralization abilities of Gm@PRP *** Gm@PRP hydrogels were subcutaneously implanted in rats for up to 4 weeks for preliminary biocompatibility followed by their transplantation into a tibial defect model for up to 8 weeks in *** defects treated with Gm@PRP hydrogels manifested significant bone regeneration as well as angiogenesis,biomineralization,and collagen *** on the biocompatibility and biological function of Gm@PRP hydrogels,a new strategy is provided for the regenerative repair of large-size bone defects.

关键词： large-sized bone defect repair platelet-rich plasma hydrogel tissue scaffold gelatin methacrylate

Facile synthesis of graphene anchored rare earth doped mixed metal ferrite nanorods:A potential candidate for azo dye mineralization

维普期刊数据库评论

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 Rare Earths 2024年第5期42卷 907-916,I0004页

作者： Tehmina Kousar muhammad Aadil Sonia Zulfiqar Sobhy mIbrahim Sidra mubeen Warda Hassan Kashuf shafiq Farzana mahmood Institute of Chemical Sciences Bahauddin Zakariya UniversityMultan60800Pakistan Department of Chemistry Rahim Yar Khan CampusThe Islarnia University of BahawalpurRahim Yar Khan64200Pakistan Department of Chemistry Faculty of ScienceUniversity of Ostrava30.Dubna 22Ostrava70103Czech Republic Department of Chemical and Biological Engineering Iowa State UniversitySweeney Hall618 Bissell RoadAmeslowa50011United States Department of Biochemistry College of ScienceKing Saud UniversityPO.Box 2455Riyadh11451Saudi Arabi Department of Chemistry The Women University Multan66000Pakistan

Bandgap tuning using rare earth metals as dopants in ferrite-based photocatalytic materials has received a lot of interest because the Fermi 4f energy of these metals generates a sub-energy state in the bandgap generated by the overlapping of Fe-3d and O-2p ***,dysprosium-doped cobalt-nickel mixed ferrite(D-CNFO)and its graphene-reinforced composite(D-CNFO@G)were prepared and an ideal photocatalyst material for azo dye mineralization was proposed.A cost-effective combination of wetchemical and ultrasonication methods was used to prepare the doped and composite *** characterization methodologies were used to scrutinize the optical,compositional,structural,morphological,and photocatalytic characteristics of as-prepared *** X-ray diffraction analysis identified the spinel phase's(cubic)structure,while the electronic spectroscopy examination confirmed the prepared samples'rod-like *** UV/visible absorbance spectrum shows the higher light harvesting behavior of the D-CNFO@G in the visible *** mineralization performance of the DCNFO and D-CNFO@G composites was analyzed using Congo-red(an anionic dye),a well-known azo *** D-CNFO@G sample removes Congo-red dye at a rate almost 2.4%faster than the D-CNFO *** experiment involving trapping free radicals indicates that hydroxyl radical play s a crucial role in dye *** the D-CNFO@G catalyst is magnetic and can be isolated easily from the photocatalytic system,it shows an awkward cycle activity of more than 96%after five mineralization *** asprepared D-CNFO@G composite is proved as an excellent option for azo dye mineralization because of the combined impacts of rare earth doping,graphene reinforcement and nanotechnology.

关键词： azo-dye Composite Graphene Dy-doped Nanotechnology Rare earths

melatonin decreases GSDmE mediated mesothelial cell pyroptosis and prevents peritoneal fibrosis and ultrafiltration failure

在线全文

学校读者我要写书评

暂无评论

Science China(Life Sciences) 2024年第2期67卷 360-378页

作者： Hongxia Ruan Xuejuan Li Lina Zhou Zihan Zheng Rulin Hua Xu Wang Yuan Wang Yujie Fan Shuwen Guo Lihua Wang shafiq ur Rahman Ziwei Wang Yuyuan Wei Shuangyan Yu Rongzhi Zhang Qian Cheng Jie Sheng Xue Li Xiaoyan Liu Ruqiang Yuan Xiaoyan Zhang Lihong Chen Guowang Xu Youfei Guan Jing Nie Hongqiang Qin Feng Zheng Advanced Institute for medical Sciences Dalian Medical UniversityDalian 116044China Department of Nephrology Second HospitalDalian Medical UniversityDalian 116023China CAS Key Laboratory of Separation Science for Analytical Chemistry Dalian Institute of Chemical PhysicsChinese Academy of SciencesDalian 116023China Chongqing International Institute for Immunology Chongqing 401320China Department of Nephrology Shenzhen HospitalSouthern Medical UniversityShenzhen 518101China Wuhu Hospital and Health Science Center East China Normal UniversityShanghai 200241China Peking University First Hospital Peking UniversityBeijing 100034China

Peritoneal fibrosis together with increased capillaries is the primary cause of peritoneal dialysis *** cell loss is an initiating event for peritoneal *** find that the elevated glucose concentrations in peritoneal dialysate drive mesothelial cell pyroptosis in a manner dependent on caspase-3 and Gasdermin E,driving downstream inflammatory responses,including the activation of ***,pyroptosis is associated with elevated vascular endothelial growth factor A and C,two key factors in vascular angiogenesis and lymphatic vessel *** deficiency mice are protected from high glucose induced peritoneal fibrosis and ultrafiltration *** of melatonin abrogates mesothelial cell pyroptosis through a mT1R-mediated action,and successfully reduces peritoneal fibrosis and angiogenesis in an animal model while preserving dialysis ***,melatonin treatment maintains mitochondrial integrity in mesothelial cells,meanwhile activating m TOR signaling through an increase in the glycolysis product dihydroxyacetone *** effects together with quenching free radicals by melatonin help mesothelial cells maintain a relatively stable internal environment in the face of high-glucose ***,melatonin treatment holds some promise in preserving mesothelium integrity and in decreasing angiogenesis to protect peritoneum function in patients undergoing peritoneal dialysis.

关键词： melatonin mitochondria pyroptosis GSDmE peritoneal fibrosis mTOR

Fault Tolerant Optical mark Recognition

在线全文

学校读者我要写书评

暂无评论

Computers, materials & Continua 2023年第2期74卷 3829-3847页

作者： Qamar Hafeez Waqar Aslam m.Ikramullah Lali shafiq Ahmad mejdal Alqahtani muhammad shafiq Department of Computer Science&IT The Islamia University of Bahawalpur63100Pakistan Department of Information Sciences The University of EducationLahore54770Pakistan Industrial Engineering Department College of EngineeringKing Saud UniversityP.O.Box 800Riyadh11421Saudi Arabia Department of Information and Communication Engineering Yeungnam UniversityGyeongsan38541Korea

Opticalmark Recognition(OmR)systems have been studied since *** is widely accepted as a data entry *** technology is used for surveys and multiple-choice *** to its ease of use,OmR technology has grown in popularity over the past two decades and is widely used in universities and colleges to automatically grade and grade student responses to *** accuracy of OmR systems is very important due to the environment inwhich they are *** relies on pixel projection or Hough transform to determine the exact answer in the *** techniques rely on majority voting to approximate a predetermined *** performance of these systems depends on precise input from dedicated *** and scanning OmR tables introduces artifacts that make table processing *** observation is a fundamental limitation of traditional pixel projection and Hough transform *** on the type of artifact introduced,accuracy is affected *** classified the types of errors and their frequency according to the artifacts in the OmR *** a major contribution,we propose an improved algorithm that fixes errors due to *** proposal is based on the Hough transform for improving the accuracy of bias correction mechanisms in OmR *** a minor contribution,our proposal also improves the accuracy of detecting markers in OmR *** results show an improvement in accuracy over existing algorithms in each of the identified *** improvement increases confidence in OmR document processing and increases efficiency when using automated OmR document processing.

关键词： Optical mark recognition fault recognition marking system

Stratified magnetohydrodynamic flow of tangent hyperbolic nanofluid induced by inclined sheet

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Applied mathematics and mechanics(English Edition) 2017年第2期38卷 271-288页

作者： T. HAYAT m. mUmTAZ A. shafiq A. ALSAEDI Department of mathematics Quaid-i-Azam University 45320 Islamabad 44000 Pakistan Nonlinear Analysis and Applied mathematics (NAAm) Research Group Department of Mathematics Faculty of Science King Abdulaziz University Jeddah 21589 Saudi Arabia Department of mathematics Preston University Kohat Islamabad Campus Islamabad 44000 Pakistan

This paper studies stratified magnetohydrodynamic （mHD） flow of tan- gent hyperbolic nanofluid past an inclined exponentially stretching surface. The flow is subjected to velocity, thermal, and solutal boundary conditions. The partial differential systems are reduced to ordinary differential systems using appropriate transformations. The reduced systems are solved for convergent series solutions. The velocity, temperature, and concentration fields are discussed for different physical parameters. The results indi- cate that the temperature and the thermal boundary layer thickness increase noticeably for large values of Brownian motion and thermophoresis effects. It is also observed that the buoyancy parameter strengthens the velocity field, showing a decreasing behavior of temperature and nanoparticle volume fraction profiles.

关键词： two-dimensional magnetohydrodynamic (mHD) flow tangent hyperbolicnanofluid mixed convection exponential stretching double stratification inclined sheet