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Chinese Journal of Structural Chemistry 2018年第6期37卷 871-877页

作者： muhammad Danish SABA Akbar muhammad Nawaz Tahir muhammad Naeem ahmed RABIA Ayub Butt muhammad Asam Raza muhammad Ashfaq Department of Chemistry University of Gujrat Department of Physics University of Sargodha Department of Chemistry University of Azad Jammu and Kashmir

Using a bidentate ligand, a Schiff base 4-（{[（Z）-（2-hydroxyphenyl）methyldene]amino}methyl）cyclohexanecarboxylic acid, complex I（ML2, where M = Cd（Ⅱ）） was synthesized and characterized by IR spectroscopy and X-ray crystallography. It crystallizes in monoclinic system, space group C2/c, M_r = 685.04, 0.34 mm × 0.26 mm × 0.14 mm, a = 54.050（3）, b = 6.1220（3）, c = 9.5081（5） A, β = 90.229（2）°, Z = 4, C_（30） H_（40） CdN_2 O_9 and V = 3146.2（3） A^3. Complex I was screened for its bactericidal activity against four bacterial strains Chromohalobactersalexigens, Chromohalobacterisraelensis, Halomonashalofila and Halomonassalina and fungicidal activity against Aspergillusnigerand Aspergillusflavus. Antimicrobial activity results showed that the synthesized complex displayed good anti-fungal activity against two fungal strains. It was found to be inactive against four different bacterial strains analyzed and was negative for bactericidal effect.

关键词： Schiff base tranexamic acid Cd XRD fungicidal activity bactericidal activity

Electric-field induced fluctuations in laser generated plasma plume

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Plasma Science and Technology 2021年第4期23卷 83-89页

作者： Rizwan ahmed Abdul JABBAR Zeshan Adeel UMAR muhammad Aslam BAIG National Centre for Physics Quaid-i-Azam University Campus45320 IslamabadPakistan

The effect of an external electric field on laser-generated plasma has been *** is observed that the laser-generated plasma can be used for the ignition of a spark in the presence of a low voltage external electric *** eight-fold emission intensity enhancement in Cu I spectral lines are measured as compared to the signal intensity in the absence of an external electric *** plasma parameters remain the same initially,up to a few microseconds after the generation of plasma,and this feature makes it more interesting for the quantitative analysis of any sample using laser induced breakdown spectroscopy(LIBS).In the presence of an external electric field,fluctuations(contraction and expansion)in the laser-generated plasma are observed which increase the plasma decay time and consequently result in enhanced signal intensity.

关键词： LIBS laser produced plasma effect of external electric plasma parameters

Chemical synthesis of zinc oxide nanorods for enhanced hydrogen gas sensing

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Chinese Physics B 2014年第1期23卷 509-512页

作者： Jabeen, Musarrat Iqbal, muhammad Azhar Kumar, R Vasant ahmed, Mansoor Javed, muhammad Tayyeb Department of Physics University of the Punjab Lahore Pakistan Department of Material Science and Metallurgy University of Cambridge England Department of Chemical Engineering Pakistan Institute of Engineering and Applied Sciences Nilore Islamabad Pakistan

Zinc oxide （ZnO） nanorods are prepared using equimolar solution of zinc nitrate （（Zn（NO3）2） and hexamethylenete- tramine （C6HleN4） by the hydrothermal technique at 80 ~C for 12 h. Epitaxial growth is explored by X-ray diffraction （XRD） patterns, revealing that the ZnO nanorods have a hexagonal （wurtzite） structure. Absorption spectra of ZnO are measured by UV-visible spectrometer. The surface morphology is investigated by field emission scanning electron mi- croscopy （FESEM）. The synthesized ZnO nanorods are used for detecting the 150 ~C hydrogen gas with a concentration over 1000 ppm. The obtained results show a reversible response. The influence of operating temperature on hydrogen gas detecting characteristic of ZnO nanorods is also investigated.

关键词： zinc oxide hydrothermal synthesis nanorods hydrogen gas sensor

Inducing opto-electronic and spintronic trends in bilayer h-BN through TMO3 clusters incorporation: Ab-initio study

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Chinese Physics B 2019年第11期28卷 284-294页

作者： Irfan ahmed muhammad Rafique Mukhtiar ahmed Mahar Abdul Sattar Larik Mohsin Ali Tunio Yong Shuai Mehran University of Engineering and Technology SZABCampusKhairpur Mirs’Pakistan School of Energy Science and Engineering Harbin Institute of TechnologyHarbin 150001China Mehran University of Engineering and Technology JamshoroSindhPakistan

The band structure, magnetism, charge distribution, and optics parameters of TMO3–h-BN hybrid systems are investigated by adopting first-principles study(FPS) calculations. It is observed that the TMO3 clusters add finite magnetic moments to bilayer h-BN(BL/h-BN), thereby making it a magnetic two-dimensional(2D) material. Spin-polarized band structures for various TMO3–BL/h-BN hybrid models are calculated. After the incorporation of TMO3, BL/h-BN is converted into semimetal or conducting material in spin up/down bands, depending on the type of impurity cluster present in BL/h-BN lattice. Optics parameters are also investigated for the TMO3–BL/h-BN complex systems. The incorporation of TMO3 clusters modifies the absorption and extinction coefficient in visible range, while static reflectivity and refraction parameter increase. It can be surmised that the TMO3 substitution in BL/h-BN is a suitable technique to modify its physical parameters thus making it functional for nano/opto-electronic applications, and an experimental approach can be adapted to reinforce the outcomes of this study.

关键词： bilayer h-BN band structure density of states magnetic moments optics

Optical sensors based on the NiPc-CoPc composite films deposited by drop casting and under the action of centrifugal force

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Chinese Physics B 2017年第6期26卷 114-118页

作者： Noshin Fatima muhammad M ahmed Khasan S Karimov Zubair Ahmad Fahmi Fariq muhammad Department of Electrical Engineering Capital University of Science and Technology (CUST) Islamabad 44000 Pakistan GIK Institute of Engineering Sciences and Technology Topi District Swabi KPK 23640 Pakistan Center for Innovative Development of Science and New Technologies of Academy of Sciences Aini 299/2 Dushanbe 734063 Tajikistan Center for Advanced Materials (CAM) Qatar University P. O. Box 2713 Doha Qatar Center for Composites Institute for Vehicle Systems & Engineering Faculty of Mechanical Engineering Universiti Teknologi Malaysia 81310 Johor Bahru Johor Malaysia Soft Materials & Devices Laboratory Department of Physics Faculty of Science and Health Koya University Danielle Mitten'and Boulevard Koya 45 Kurdistan Region Iraq

In this study, solution processed composite films of nickel phthalocyanine（NiPc） and cobalt phthalocyanine（CoPc）are deposited by drop casting and under centrifugal force. The films are deposited on surface-type inter-digitated silver electrodes on ceramic alumina substrates. The effects of illumination on the impedance and capacitance of the NiPc–CoPc composite samples are investigated. The samples deposited under centrifugal force show better conductivity than the samples deposited by drop casting technique. In terms of impedance and capacitance sensitivities the samples fabricated under centrifugal force are more sensitive than the drop casting samples. The values of impedance sensitivity（Sz）are equal to（-1.83） MΩ·cm^2/mW and（-5.365） MΩ·cm^2/mW for the samples fabricated using drop casting and under centrifugal force, respectively. Similarly, the values of capacitance sensitivity（Sc） are equal to 0.083 pF·cm^2/mW and 0.185 pF·cm～2/mW for the samples fabricated by drop casting and under centrifugal force. The films deposited using the different procedures could potentially be viable for different operational modes（i.e., conductive or capacitive） of the optical sensors. Both experimental and simulated results are discussed.

关键词： optical sensors capacitive mode impedance mode centrifugal deposition

Identification of three major Bemisia tabaci biotypes in China based on morphological and DNA polymorphisms

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Progress in Natural Science:Materials International 2009年第6期19卷 713-718页

作者： muhammad Z.ahmed Vartika Mathur Department of Entomology South China Agricultural University Department of Zoology Sri Venkateswara CollegeUniversity of Delhi

The sweet potato whitefly, Bemisia tabaci, is a complex species, and many of its biotypes are important agricultural pests. The B and Q biotypes are invasive and coexist with the native Cv biotype on vegetable and ornamental crops in China. In this study, these three bio- types were identified based on their morphological characteristics, RAPD-PCR analysis, and DNA sequences of the COI gene. The ante-rior and posterior wax fringes of the B, Q, and Cv biotypes significantly differed from each other. Based on this morphological characteristic, the three biotypes can easily be distinguished in greenhouses and fields. Genomic DNA RAPD-PCR band patterns also revealed differences between these biotypes using the H16 primer. The B biotype has three bright DNA bands between 250 and 600 bp, the Q biotype only has one bright band at 300 bp, while the Cv biotype has no band between 250 and 500 bp. Both the Cv and Q biotypes have two bright bands at 750 and 1000 bp while the B biotype has only one band at 1000 bp. Based on the COI gene, the genetic identity between B and Cv, B and Q, and Q and CV was 85.8%, 94.7%, and 86.0%, respectively. The MP tree indicated that the phylogenetic relationship between the B and Q biotypes is much closer than that between the B and Cv or the Q and Cv biotypes. The uses of the morphological, RAPD-PCR, and DNA sequencing methods in biotype identification of B. tabaci are discussed.

关键词： Bemisia tabaci complex Biotype DNA polymorphism Identification Morphology

3-D seismic interpretation of stratigraphic and structural features in the Upper Jurassic to Lower Cretaceous sequence of the Gullfaks Field,Norwegian North Sea:A case study of reservoir development

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Energy Geoscience 2021年第4期2卷 287-297页

作者： muhammad Usman Numair ahmed Siddiqui Eduardo Garzanti muhammad Jamil Qazi Sohail Imran Luqman ahmed Laboratory for Provenance Studies Department of Earth and Environmental SciencesUniversity of Milano-BicoccaPiazza Della Scienza 420126MilanoItaly Geoscience Department Universiti Teknologi PETRONASSeri Iskandar32610PerakMalaysia Shale Gas Research Group Institute of Hydrocarbon RecoveryUniversiti Teknologi PETRONASSeri Iskandar32610PerakMalaysia Institute of Geology University of the PunjabLahore56300Pakistan

The 3-D seismic dataset is a key tool to analyze and understand the mechanism of structural and stratigraphic hydrocarbon(HC)trapping in the *** used subsurface seismic characterization methods for fractures are based on the theory of effective anisotropy *** aim of this work is to improve the structural images with dense sampling of 3-D survey to evaluate structural and stratigraphic models for reservoir development to predict reservoir *** present study of the Gullfaks Field,located in the Norwegian North Sea Gullfaks sector,identifies the shallowest structural *** steepness of westward structural dip decreases eastward during the Upper Jurassic to Lower Cretaceous *** sands consist of the Middle Jurassic deltaic deposits and Lower Jurassic fluvial channel and delta plain *** supply steadily prevails on sea-level rise and the succession displays a regressive trend indicated by a good continuous stacking *** key factor for the development of reservoirs in the Gullfaks Field is fault transmissibility with spatially distributed *** majority of mapped faults with sand-to-sand contacts are non-sealing,which provide restriction for the HC flow between the fault *** traps for HC accumulation occur between the post-rift and syn-rift strata,*** set by extensional system,unconformity trap at the top of syndeposition,and structural trap due to normal *** reservoir quality in the studied area is generally excellent with average 35%porosity and permeability in the Darcy *** findings are useful to better understand the development of siliciclastic reservoirs in similar geological settings worldwide.

关键词： 3-D seismic model Mesozoic stratigraphic boundary Structural trap Reservoir quality Gullfaks Field

Darcy–Forchheimer Three-Dimensional Flow of Williamson Nanofluid over a Convectively Heated Nonlinear Stretching Surface

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Communications in Theoretical Physics 2017年第9期67卷 387-394页

作者： Tasawar Hayat Arsalan Aziz Taseer muhammad ahmed Alsaedi Department of Mathematics Quaid-I-Azam University Nonlinear Analysis and Applied Mathematics (NAAM) Research Group Department of Mathematics Faculty of ScienceKing Abdulaziz University

The present study elaborates three-dimensional flow of Williamson nanoliquid over a nonlinear stretchable surface. Fluid flow obeys Darcy–Forchheimer porous medium. A bidirectional nonlinear stretching surface generates the flow. Convective surface condition of heat transfer is taken into consideration. Further the zero nanoparticles mass flux condition is imposed at the boundary. Effects of thermophoresis and Brownian diffusion are considered. Assumption of boundary layer has been employed in the problem formulation. Convergent series solutions for the nonlinear governing system are established through the optimal homotopy analysis method(OHAM). Graphs have been sketched in order to analyze that how the velocity, temperature and concentration distributions are affected by distinct emerging flow parameters. Skin friction coefficients and local Nusselt number are also computed and discussed.

关键词： three-dimensional flow Williamson fluid nanoparticles Darcy-Forchheimer porous medium con-vective boundary condition nonlinear stretching surface

Is Ziarat a Potential Site for Conventional or Unconventional Energy Resources?

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Acta Geologica Sinica(English Edition) 2018年第4期92卷 1544-1557页

作者： Sarfraz KHAN Umair Bin NISAR Khawar A.ahmed muhammad WASEEM Waqas ahmed National Centre of Excellence in Geology University of PeshawarPeshawar25130Pakistan Comsats Institute of Information and Technology AbbottabadPakistan Comsats Institute of Information and Technology IslamabadPakistan

A structural interpretation of the Ziarat block in the Balochistan region （a part of the Suleiman Fold and Thrust Belt） has been carried out using seismic and seismological data. Seismic data consists of nine 2.5D pre-stack migrated seismic lines, whereas the seismological data covers the Fault Plane Solution and source parameters. Structural interpretation describes two broad fault sets of fore and back thrusts in the study area that have resulted in the development of pop-up structures, accountable for the structural traps and seismicity pattern in terms of seismic hazard. Seismic interpretation includes time and depth contour maps of the Dungan Formation and Ranikot group, while seismological interpretation includes Fault Plane Solution, that is correlated with a geological and structural map of the area for the interpretation of the nature of the subsurface faults. Principal stresses are also estimated for the Ranikot group and Dungan Formation. In order to calculate anisotropic elastic properties, the parameters of the rock strength of the formations are first determined from seismic data, along with the dominant stresses （vertical, minimum horizontal, and maximum horizontal）. The differential ratio of the maximum and minimum horizontal stresses is obtained to indicate optimal zones for hydraulic fracturing, and to assess the potential for geothermal energy reservoir prospect generation. The stress maps indicate high values towards the deeper part of the horizon, and low towards the shallower part, attributed to the lithological and structural variation in the area. Outcomes of structural interpretation indicate a good correlation of structure and tectonics from both seismological and seismic methods.

关键词： fault plane solution reservoir monitoring stress analysis hydraulic fracturing geothermal energy structural interpretation

Vehicle Detection in Challenging Scenes Using CenterNet Based Approach

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Computers, Materials & Continua 2023年第2期74卷 3647-3661页

作者： Ayesha muhammad Javed Iqbal Iftikhar Ahmad Madini OAlassafi ahmed SAlfakeeh ahmed Alhomoud Department of Computer Science University of Engineering and Technology Taxila47050Pakistan Faculty of Computing and Information Technology King Abdulaziz University Jeddah21589Saudi Arabia Faculty of Computing and Information Technology Northern Border UniversityRafhaSaudi Arabia

Contemporarily numerous analysts labored in the field of Vehicle detection which improves Intelligent Transport System(ITS)and reduces road *** major obstacles in automatic detection of tiny vehicles are due to occlusion,environmental conditions,illumination,view angles and variation in size of *** research centers on tiny and partially occluded vehicle detection and identification in challenging scene specifically in crowed *** this paper we present comprehensive methodology of tiny vehicle detection using Deep Neural Networks(DNN)namely *** DNN disregards objects that are small in size 5 pixels and more false positives likely to happen in crowded *** there are two categories of deep learning models single-step and two-step.A single forward pass model is the one in which detection is performed directly to possible location over dense sampling,wherein two-step models incorporated by Region proposals followed by object *** in this research scrutinize one-step State of the art(SOTA)model CenteNet as proposed recently with three different feature extractor ResNet-50,HourGlass-104 and ResNet-101 one by *** train our model on challenging KITTI dataset which outperforms in comparison with SOTA single-step technique MSSD300∗which depicts performance improvement by 20.2%mAPandSMOKEby with 13.2%mAP *** of CenterNet can be justified through the huge improved *** performance of our model is evaluated on KITTI(Karlsruhe Institute of Technology and Toyota Technological Institute)benchmark dataset with different backbones such as ResNet-50 gives 62.3%mAP ResNet-10182.5%mAP,last but not the least HourGlass-104 outperforms with 98.2%mAP CenterNet-HourGlass-104 achieved high mAP among above mentioned feature *** also compare our model with other SOTA techniques.

关键词： CenteNet SOTA object detection deep learning MSSD SMOKE DNN KITTI