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Journal of Marine Science and Application 2021年第4期20卷 621-631页

作者： Siti Ayishah Thaminah Hikmatullah Sahib muhammad Zahir Ramli muhammad Afq Azman muhammad Mazmirul Abd Rahman Mohd Fuad Miskon Ef Helmy Arifn muhammad hafeez jeofry Kamaruzzaman Yunus Department of Marine Science Kulliyyah of ScienceInternational Islamic University Malaysia(IIUM)25200 KuantanMalaysia Institute of Oceanography&Maritime Studies(INOCEM) Kulliyyah of ScienceInternational Islamic University Malaysia(IIUM)25200 KuantanMalaysia Faculty of Science and Marine Environment Universiti Malaysia Terengganu21200 Kuala NerusMalaysia

In many cases of wave structure interactions,three-dimensional models are used to demonstrate real-life complex environ-ments in large domain *** the seakeeping context,predicting the motion responses in the interaction of a long body resembling a ship structure with regular waves is crucial and can be *** this work,regular waves interacting with a rigid foating structure were simulated using the open-source code based on the weakly compressible smoothed par-ticle hydrodynamics(WCSPH)method,and optimal parameters were suggested for diferent wave *** displacements were computed,and their response amplitude operators(RAOs)were found to be in good agreement with experimental,numerical,and analytical *** of numerical and experimental RAOs tended to increase at low wave frequencies,particularly at amidships and near the *** addition,the instantaneous wave contours of the sur-rounding model were examined to reveal the efects of localized waves along the structure and wave *** results indicated that the motion response from the WCSPH responds well at the highest frequency range(ω>5.235 rad/s).

关键词： DualSPHysics Response amplitude operators Seakeeping Wave structure interaction Weakly compressible

Effect of thermomechanical cyclic quenching and tempering treatments on microstructure,mechanical and electrochemical properties of AISI 1345 steel

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International Journal of Minerals,Metallurgy and Materials 2021年第4期28卷 688-698页

作者： muhammad Arslan hafeez Ameeq Farooq Kaab Bin Tayyab and muhammad Adnan Arshad School of Civil and Environmental Engineering National University of Sciences and TechnologyIslamabad 44000Pakistan Department of Metallurgy&Materials Engineering University of the Punjab54590 LahorePakistan

Thermomechanical cyclic quenching and tempering(TMCT)can strengthen steels through a grain size reduction *** effect of TMCT on microstructure,mechanical,and electrochemical properties of AISI 1345 steel was *** samples heated to 1050℃,rolled,quenched to room temperature,and subjected to various cyclic quenching and tempering heat treatments were named TMCT-1,TMCT-2,and TMCT-3 samples,*** analysis revealed that microstructures of all the treated samples contained packets and blocks of well-refined lath-shaped martensite and retained austenite phases with varying grain sizes(2.8–7.9μm).Among all the tested samples,TMCT-3 sample offered an optimum combination of properties by showing an improvement of 40%in tensile strength and reduced 34%elongation compared with the non-treated *** results were in good agreement with mechanical tests as the TMCT-3 sample exhibited a 51%improvement in indentation hardness with almost identical reduced elastic modulus compared with the non-treated *** electrochemical properties were analyzed in 0.1 M NaHCO_(3) solution by potentiodynamic polarization and electrochemical impedance *** a result of TMCT,the minimum corrosion rate was 0.272 mm/a,which was twenty times less than that of the nontreated *** impedance results showed the barrier film mechanism,which was confirmed by the polarization results as the current density decreased.

关键词： thermomechanical treatment cyclic heat-treatment nanoindentation potentiodynamic polarization electrochemical impedance spectroscopy

Syntheses, Characterization and Crystal Structures of Two Novel Oxazoline Based Titanium Complexes

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Chinese Journal of Structural Chemistry 2015年第7期34卷 1121-1134页

作者： muhammad hafeez muhammad Naeem Ahmed SONJA Lippert WINFRIED P.Krtetschmer Department of Chemistry The University of Azad Jammu and Kashmir Inorganic Chemistry II University of Bayreuth

Two novel titanium compounds [（E）-N＇-（2,6-diisopropylphenyl）-N-（2-（4,4-dimethyl-4,5-dihydrooxazol-2-yl）phenyl）benzimidamido]titanium trichloride（1） and [N-（2-（4,4-dimethyl-4,5-dihydrooxaz-ol-2-yl）phenyl）-6-（2,4,6-triisopropyl-phenyl） pyridin-2-amido]titanium trichloride（2） were synthesized by reacting the corresponding ligand with diethylaminetitaniumtrichloride in equal molar ratios. The compounds were characterized with 1H, 13 C NMR, elemental analysis and single-crystal X-ray diffraction analysis. The geometry of both compounds is distorted octahedron. The three nitrogen and one chlorine atoms are in the equatorial plane. Compound 1 crystallizes in orthorhombic system, space group P212121 with a = 10.3520（4）, b = 16.5750（7）, c = 17.1530（7） , Z = 4 and V = 2943.2（2）3. Compound 2 crystalizes in the monoclinic system, space group P21/n with a = 15.6400（11）, b = 10.12.60（7）, c = 22.9120（14）, Z = 4 and V = 3558.5（4）3. The synthesized compounds were employed for ethylene polymerization catalysis. Both complexes showed moderate activity when activated with dry methylaluminoxane（d MAO） and complex 1 produced very high molecular weight polyethylene.

关键词： octahedron polymerization titanium trichloride X-ray

UV Assisted Preliminary DNA Binding Studies and Single-crystal X-ray Structure of 4-{(4-Nitrophenyl-sulfonamido)methyl}cyclohexanecarboxylic Acid

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Chinese Journal of Structural Chemistry 2017年第5期36卷 745-750页

作者： muhammad Danish RABIA Ayub Butt muhammad Nawaz Tahir muhammad Ashfaq SYEDA Tahira hafeez Department of Chemistry University of GujratGujrat 50700Pakistan Department of Physics University of SargodhaSargodhaPakistan

A new sulfonamide, 4-{（4-nitrophenylsulfonamido）methyl}cyclohexanecarboxylic acid（C14H18N2O6S）, has been synthesized by the reaction of tranexamic acid and 4-nitrobenzenesulfonyl chloride in basic medium at room temperature. The molecular structure was determined by FT-IR, NMR, elemental analysis and single-crystal X-ray technique. X-ray diffraction shows that the compound crystallizes in the monoclinic system, space group P21/c with a = 13.5980（7）, b = 4.9877（2）, c = 23.3878（13） A, β = 93.254（3）°, Z = 4, V = 1583.67（14） A3, μ = 0.237 mm-1, F（000） = 720, R = 0.0471 and w R = 0.1182. The molecules are related by inversion and paired into dimers via C–H…O interactions. The dimmers are interlinked due to strong N–H…O bonds, where O-atoms are of sulfonyl groups. The molecules are stabilized in the form of infinite two-dimensional network with base vectors [0 1 0] and [0 0 –1] in the plane（1 0 2）. The existence of good intermolecular interactions suggests the biological importance of the synthesized molecule. The compound was screened for its interaction with FS-DNA using UV-visible spectroscopy. UV-visible spectroscopic results depict that the compound interacts with DNA by mixed binding mode intercalation along with hydrogen bonding. Negative values of ΔG（–23.34, –17.79 k J·mol-1） indicate spontaneity of the compound-DNA adduct formation.

关键词： sulfonamide tranexamic acid 4-nitrobenzenesulfonyl chloride XRD FS-DNA,intercalation

Deciphering the role of rGO in tuning dielectric properties of Er_(2)O_(3)/ZnO/rGO nanocomposites synthesized via facile approach

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Journal of Rare Earths 2024年第3期42卷 578-585,I0006页

作者： Saiqa hafeez Saima Perveen muhammad Zarrar Khan Awab Hashmi Fahad Azad School of Natural Sciences(SNS) National University of Sciences and Technology(NUST)IslamabadPakistan Electronic and Magnetic Materials Laboratory School of Chemical and Materials Engineering(SCME)National University of Sciences and Technology(NUST)IslamabadPakistan

The present research investigated the effect of reduced graphene oxide(rGO) integration with assynthesized Er_(2)O_(3)/ZnO nanocomposites on dielectric properties. The samples were characterized by Xray diffraction(XRD), Fourier transform infrared spectroscopy(FTIR), scanning electron microscopy(SEM), diffuse reflectance spectroscopy(DRS), and energy dispersive spectroscopy(EDS). Complex impedance spectroscopy was utilized to characterize dielectric relaxation phenomena in Er_(2)O_(3)/ZnO and Er_(2)O_(3)/ZnO/rGO nanocomposites. All the samples exhibit single relaxation phenomena which are ascribed to grain boundaries. The addition of rGO to Er_(2)O_(3)/ZnO nanocomposite results in the enhancement of dielectric response due to increased local field intensity caused by the formation of conductinginsulating interfaces. Furthermore, the AC conductivity of the Er_(2)O_(3)/ZnO/rGO is increased at higher frequencies due to the presence of free charge carriers in rGO. At higher frequencies, Er_(2)O_(3)/ZnO/rGO nanocomposite with increased concentration of ZnO exhibits a more stable dielectric constant with extremely low dielectric loss. Hence, the inclusion of rGO in Er_(2)O_(3)/ZnO nanocomposites makes it a novel prospective candidate in the field of energy storage devices.

关键词： Erbium oxide(Er_(2)O_(3)) Rare earths Stable dielectric constant Impedance Polarization Grain boundaries

Influence of Seed Priming on Performance and Water Productivity of Direct Seeded Rice in Alternating Wetting and Drying

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Rice science 2015年第4期22卷 189-196页

作者： hafeez Ur REHMAN muhammad KAMRAN Shahzad Maqsood Ahmed BASRA Irfan AFZAL muhammad FAROOQ Department of Agronomy University of AgricultureFaisalabad Institute of Agriculture University of Western Australia College of Food and Agricultural Sciences King Saud University

Direct seeded rice is promising alternative to traditional transplanting, but requires appropriate crop and water management to maintain yield performance and achieve high water productivity. Present study evaluated the effect of seed priming and irrigation on crop establishment, tillering, agronomic traits, paddy yield, grain quality and water productivity of direct seeded rice in alternate wetting and drying （DSR-AWD） in comparison with direct seeded rice at field capacity （DSR- FC）. Seed priming treatments were osmo-priming with KCI （2.2%）, CaCI2 （2.2%） and moringa leaf extracts （MLE, 3.3%） including hydro-priming as control. Among the treatments, seed osmo-primed with MLE emerged earlier and had higher final emergence, followed by osmo-priming with CaCI2. Tillering emergence rate and number of tillers per plant were the highest for seed priming with CaCI2 in DSR- AWD. Total productive and non-productive tillers, panicle length, biological and grain yields, harvest index were highest for seed priming with MLE or CaCI2 in DSR-AWD. Similarly, grain quality, estimated in terms of normal grains, abortive and chalky grains, was also the highest in DSR-AWD with MLE osmo-priming. Benefit cost ratio and water productivity was also the highest in DSR-AWD for seed priming with MLE. In conclusion, seed priming with MLE or CaCI2 can be successfully employed to improve the direct seeded rice performance when practiced with alternate wetting and drying irrigation.

关键词： crop establishment grain filling rate seed priming water productivity yield direct seededrice alternating wetting and drying grain quality

Image-Based Automatic Energy Meter Reading Using Deep Learning

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Computers, Materials & Continua 2023年第1期74卷 203-216页

作者： muhammad Imran hafeez Anwar muhammad Tufail Abdullah Khan Murad Khan Dzati Athiar Ramli Institute of Computer Sciences and Information Technology Faculty of Management and Computer SciencesThe University of AgriculturePeshawarPakistan Department of Electrical and Computer Engineering COMSATS University IslamabadAttock CampusAttock CityPakistan Kuwait College of Science and Technology Kuwait CityKuwait School of Electrical&Electronic Engineering USM Engineering CampusUniversiti Sains MalaysiaPenang14300Malaysia

We propose to perform an image-based framework for electrical energy meter *** aim is to extract the image region that depicts the digits and then recognize them to record the consumed *** the readings of serial numbers and energy meter units,an automatic billing system using the Internet of Things and a graphical user interface is deployable in a real-time ***,such region extraction and character recognition become challenging due to image variations caused by several factors such as partial occlusion due to dust on the meter display,orientation and scale variations caused by camera positioning,and non-uniform illumination caused by *** this end,our work evaluates and compares the stateof-the art deep learning algorithm You Only Look Once(YOLO)along with traditional handcrafted features for text extraction and *** image dataset contains 10,000 images of electrical energymeters and is further expanded by data augmentation such as in-plane rotation and scaling tomake the deep learning algorithms robust to these image *** training and evaluation,the image dataset is annotated to produce the ground truth of all the ***,YOLO achieves superior performance over the traditional handcrafted features with an average recognition rate of 98%for all the *** proves to be robust against the mentioned image variations compared with the traditional handcrafted *** proposed method can be highly instrumental in reducing the time and effort involved in the currentmeter reading,where workers visit door to door,take images ofmeters and manually extract readings from these images.

关键词： Convolutional neural network object localization machine learning

4-((4-Chlorophenylsulfonamido)methyl)cyclohexanecarboxylic Acid： Synthesis, Crystal Structure and Biological Activities

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Chinese Journal of Structural Chemistry 2017年第8期36卷 1307-1314页

作者： muhammad Danish RABIA Ayub Butt muhammad Nawaz Tahir muhammad Ashfaq SYEDA Tahira hafeez muhammad Naeem Ahmed HALEEMA Qureshi Department of Chemistry University of Gujrat Gujrat 50700 Pakistan Department of Physics University of Sargodha Sargodha Pakistan Department of Chemistry University of Azad Jammu and Kashmir Muzaffarabad 13100 Pakistan

In this study, a novel 4-（（4-chlorophenylsulfonamido）methyl）cyclohexanecarboxylic acid（C（14）H（18）ClNO4S） was synthesized by the reaction of tranexamic acid and 4-chlororbenzene sulfonyl chloride in basic medium at room temperature. The molecular structure was determined by FT-IR, NMR, elemental analysis and single-crystal X-ray analysis. The compound crystallizes in the monoclinic system, space group P21/c with a = 12.3120（11）, b = 16.5987（19）, c = 7.6873（7）？, β = 90.495（6）o, Z = 4 and V = 1570.9（3）？~3, crystal size（mm） = 0.38 × 0.16 × 0.14 and Rint = 0.045. In this compound, the carboxylic acid A（O（1）/C（1）/C（2）） and the sulfonyl B（O（3）/S（1）/O（4）） moieties are of course planar. The molecules are dimerized due to the O–H…O type of H-bonding with the R22（8） ring motifs. The dimmers are interlinked through C–H…O and N–H…O types of H-bonding. The synthesized compound was screened against four bacterial and two fungal strains and inactive against all strains. Antioxidant activity was checked against DPPH. Enzyme inhibition activity was carried out using three different enzymes and the title compound was more potent α-chymotrypsin inhibitor.

关键词： sulfonamide tranexamic acid 4-chlorobenzenesulfonyl chloride XRD biological applications

Molecular dynamics simulation of nanoscale surface diffusion of heterogeneous adatoms clusters

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Chinese Physics B 2016年第7期25卷 341-348页

作者： muhammad Imran Fayyaz Hussain muhammad Rashid muhammad Ismail hafeez Ullah Yongqing Cai M Arshad Javid Ejaz Ahmad S A Ahmad Material Simulation Research Laboratory(MSRL) Department of PhysicsBahauddin Zakariya UniversityMultan 60800Pakistan Department of Physics COMSATS Institute of Information Technology44000 IslamabadPakistan Department of Physics Govt.College University FaisalabadLayyah CampusLayyah 31200Pakistan Institute of High Performance Computing A*STARSingapore 138632Singapore Department of Basic Sciences(Physics) UETTaxila Department of Physics Simulation Laboratorythe Islamia University of Bahawalpur63100Pakistan

Molecular dynamics simulation employing the embedded atom method potential is utilized to investigate nanoscale surface diffusion mechanisms of binary heterogeneous adatoms clusters at 300 K, 500 K, and 700 K. Surface diffusion of heterogeneous adatoms clusters can be vital for the binary island growth on the surface and can be useful for the formation of alloy-based thin film surface through atomic exchange process. The results of the diffusion process show that at 300 K, the diffusion of small adatoms clusters shows hopping, sliding, and shear motion; whereas for large adatoms clusters（hexamer and above）, the diffusion is negligible. At 500 K, small adatoms clusters, i.e., dimer, show almost all possible diffusion mechanisms including the atomic exchange process; however no such exchange is observed for adatoms clusters greater than dimer. At 700 K, the exchange mechanism dominates for all types of clusters, where Zr adatoms show maximum tendency and Ag adatoms show minimum or no tendency toward the exchange process. Separation and recombination of one or more adatoms are also observed at 500 K and 700 K. The Ag adatoms also occupy pop-up positions over the adatoms clusters for short intervals. At 700 K, the vacancies are also generated in the vicinity of the adatoms cluster,vacancy formation, filling, and shifting can be observed from the results.

关键词： molecular dynamics surface diffusion adatoms atomic exchange

Water extractable plant nutrients in soils amended with cow manure co-composted with maple tree residues

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International Journal of Agricultural and Biological Engineering 2018年第5期11卷 167-173页

作者： Zobia Anwar muhammad Irshad An Ping Farhan hafeez Shao Yang Department of Environmental Sciences COMSATS University IslamabadAbbottabad CampusAbbottabad 22060Pakistan Arid Land Research Center Tottori UniversityHamasaka cho Tottori 680-0001Japan

Studies on the availability of plant nutrients in soils treated with manure co-composted feed-stocks are very *** present investigation aimed at studying the nutrient release pattern from three soils amended with maple tree leaves co-composted with cow *** were mixed with the compost at the rate of 20 t/hm^(2) and incubated at room *** to incubation,plants residue samples were analyzed for total elemental concentrations(NO_(3),NH_(4),P,K,Ca,Mg,Na,Zn,Mn,Fe,Cu,Ni and Cd).Water extractability of nutrients from soils was affected by the type of soil and ratio of composted manure *** NH_(4),P,K,Ca and Mg concentrations varied in the descending order of sandy clay,sandy loam and silt loam except NO_(3).The concentrations of P,K,Ca and Mg in the amended soils increased with the ratio of manure co-composted with leaf litter while those of NO_(3),NH_(4) and trace elements *** residual nutrients in soil varied directly with their contents in the compost ***-composting improved the availability of nutrients in soils and this should be an ideal approach to managing the enormous waste generated from the livestock sector for restoring soil fertility.

关键词： macro-elements micro-elements varied textured soils co-composting cow manure maple plant residues