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Synthesis,Crystal Structure and Spectroscopic Properties of 1,2-Benzothiazine Derivatives:An Experimental and DFT Study

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Chinese Journal of Structural Chemistry 2015年第1期34卷 15-25页

作者： muhammad nadeem arshad TARIQ Mahmood ATHER Faroque Khan muhammad Zia-Ur-Rehman ABDULLAH M.Asiri ISLAM Ullah Khan RIFFAT-Un-Nisa KHURSHID Ayub AZAM Mukhtar muhammad Tariq Saeed Chemistry Department Faculty of ScienceKing Abdulaziz University Centre of Excellence for Advanced Materials Research (CEAMR) King Abdulaziz University Department of Chemistry COMSATS Institute of Information TechnologyAbbottabad IRCBM COMSATS Institute of Information Technology Applied Chemistry Research Center PCSIR Laboratories ComplexFerozpur RoadLahore 54600Pakistan Materials Chemistry Laboratory Department of ChemistryGC University Department of Chemistry College of ScienceKing Faisal University Department of Chemistry University of EducationOkara CampusOkara-Pakistan

1,2-Benzothiazine derivatives methyl 3-methoxy-4-oxo-3,4-dihydro-2H-benzo[e] [1,2]thiazine-3-carboxylate 1,1-dioxide（1） and methyl 2-ethyl-3-hydroxy-4-oxo-3,4-dihydro-2Hbenzo[e][1,2]thiazine-3-carboxylate 1,1-dioxide（2） were synthesized, and characterized by spectroscopic techniques; 1H-NMR and infrared（IR） spectroscopy. Crystals of 1 and 2 were grown by slow evaporation of methanol and ethyl acetate, respectively and their crystal structures were investigated by single-crystal X-ray diffraction analysis. Geometric properties were calculated by the B3 LYP method of density functional theory（DFT） at the 6-31G＋（d） basis set to compare with the experimental data. Simulated properties were found in strong agreement with the experimental ones. Intermolecular forces have also been modeled in order to investigate the strength of packing and strong hydrogen bonding was observed in both compounds 1 and 2. Electronic properties such as Ionization Potential（IP）, Electron Affinities（EA） and coefficients of the highest occupied molecular orbital（HOMO） and the lowest unoccupied molecular orbital（LUMO） of com- pounds 1 and 2 were simulated for the first time.

关键词： 1,2-benzothiazine B3LYP/6-31+G (d) density functional theory (DFT) HUMO-LUMO crystal structures

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One-pot Multicomponent Synthesis, Spectroscopy, Crystal Structures and Theoretical Calculations of 3-Cyano-4-(4-hydroxy-3-methoxyphenyl)-6-phenyl-2(1H)-pyridinone and 3-Cyano-4-chlorophenyl-6-(4-tolyl)-2(1H)-pyridinone

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Chinese Journal of Structural Chemistry 2019年第3期38卷 448-463页

作者： muhammad nadeem arshad HASSAN M.Faidallah ABDULLAH M.Asiri OSMAN I.Osman FAISAL M.S.Aqlan Chemistry Department Faculty of Science King Abdulaziz University Centre of Excellence for Advanced Materials Research (CEAMR) King Abdulaziz University Department of Chemistry University of Jeddah Department of Chemistry University of IBB

Pyridinone derivatives are of great interest in medicinal chemistry where they were found to be potent to various diseases. Their metal complexes added more value to their applications. Here, we have synthesized two 2-pyridinone derivatives(3-cyano-4-(4-hydroxy-3-methoxyphenyl)-6-phenyl-2(1 H)-pyridinone and 3-cyano-4-chlorophenyl-6-(4-tolyl)-2(1 H)-pyridinone) using one-pot multicomponent system. They were well characterized using spectroscopic techniques like nuclear magnetic resonance(NMR-1 H & 13 C), Fourier transform infrared(FT-IR) and UV/Vis spectroscopy. The final structures were determined using single-crystal X-ray diffraction technique which helps us to determine their geometries. Density functional theory(DFT) and time-dependent density functional theory(TD-DFT) with suitable basis-sets of calculations have correctly simulated these spectroscopic parameters. The intramolecular charge transfer(ICT) of both substrates has been discussed using natural bond orbital(NBO) technique. Molecular electrostatic potential(MEP) surfaces showed their reactive locations for intermolecular charge transfer. Compared to p-nitroaniline(pNA), both substrates were shown to have substantial molecular hyperpolarizability.

关键词： crystal structures NBO one-pot multicomponent system 2-pyridinone TD-DFT

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Interaction of ciprofloxacin hydrochloride with sodium dodecyl sulfate in aqueous/electrolytes solution at different temperatures and compositions

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Chinese Journal of Chemical Engineering 2020年第1期28卷 216-223页

作者： Sk.Md.Ali Ahsan Md.Ruhul Amin Shamim Mahbub Mohammad Robel Molla Shahina Aktar Malik Abdul Rub Md.Anamul Hoque muhammad nadeem arshad Mohammed Abdullah Khan Department of Chemistry Jahangirnagar UniversitySavarDhaka 1342Bangladesh Chemistry Department Faculty of ScienceKing Abdulaziz UniversityJeddah-21589Saudi Arabia Center of Excellence for Advanced Materials Research King Abdulaziz UniversityJeddah-21589Saudi Arabia

Interactions of ciprofloxacin hydrochloride(CPFH)with sodium dodecyl sulfate(SDS)were investigated by conductivity measurement in H2O/electrolyte solutions(NaCl,Na2SO4&Na3PO4)over 298.15–318.15 K temperature range(with 5 K interval)considering the human body *** all cases,two critical micelle concentrations(c*)were observed which are increased in the presence of drug and decreased in the presence of salts enunciating the presence of interaction amongst the studied ***(CPFH+SDS)system in the presence of salt,the c*values at 303.15 K and I=0.50 mmol·kg^-1 followed the order:CNaCl>CNa2SO4>***ΔG1,m0 andΔG2,m0values are found to be negative for all systems that show that the micellization process is thermodynamically ***(CPFH+SDS)system in water,theΔHm0&ΔSm0 values reveal that the micellization processes is both entropy dominated in almost all *** the occurrence of electrolytes,ΔHm0 andΔSm0 values indicate that micellization processes are both entropy&enthalpy restricted at upper temperature but it becomes totally entropy dependent at higher *** higher positiveΔSm0 values indicate the enhanced hydrophobic interaction in presence of *** enthalpy-entropy compensation was determined from the linear relationship betweenΔHm0 andΔSm0 values in every *** transfer energies as well as compensation temperature and intrinsic enthalpy were also evaluated and the behaviors were comparable to other biological system.

关键词： Ciprofloxacin hydrochloride Sodium dodecyl sulfate Critical micelle concentration Thermodynamic indices Hydrophobic effect

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Carbon-supported PtCo_2Ni_2 alloy with enhanced activity and stability for oxygen reduction

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Science China Materials 2015年第3期58卷 179-185页

作者：郑亚荣高敏锐李会会高强 muhammad nadeem arshad Hassan A.Albar Tariq R.Sobahi 俞书宏 Division of Nanomaterials & Chemistry Hefei National Laboratory for Physical Science at MicroscaleCollaborative Innovation Center of Suzhou Nano Science and TechnologyDepartment of ChemistryUniversity of Science and Technology of China Center of Excellence for Advanced Materials Research King Abdulaziz University Chemistry Department Faculty of ScienceKing Abdulaziz University

The commercialization of proton exchange membrane fuel cells(PEMFCs) is still restricted by the well-known dilemma,that is,the heavy dependence of using expensive plantinum(Pt) catalyst to negotiate the sluggish oxygen reduction reaction(ORR) kinetics in fuel cell ***,a carbon-supported PtC o2Ni2 alloy catalyst with low Pt usage was synthesized via a simple method,which exhibited exceptional ORR activity with a more positive half-wave potential(E1/2) ~57 m V,which was more positive than the state-of-the-art Pt/C ***,the alloy catalyst performs excellent durability after 10,000 harsh cycles compared with that of Pt/C catalyst in acidic solution,which may be developed as a promising alternative for Ptbased catalysts in fuel cell technology.

关键词：合金催化剂 Pt ORR Ni Co HRTEM

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Recognizing Breast Cancer Using Edge-Weighted Texture Features of Histopathology Images

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Computers, Materials & Continua 2023年第10期77卷 1081-1101页

作者： Arslan Akram Javed Rashid Fahima Hajjej Sobia Yaqoob muhammad Hamid Asma arshad nadeem Sarwar Department of Computer Science and Information Technology Superior UniversityLahore54000Pakistan MLC Lab Maharban HouseHouse#209Zafar ColonyOkara56300Pakistan Information Technology Services University of OkaraOkara56300Pakistan Department of CS&SE International Islamic UniversityIslamabad44000Pakistan Department of Information Systems College of Computer and Information SciencesPrincess Nourah bint Abdulrahman UniversityRiyadh11671Saudi Arabia Department of Computer Science University of OkaraOkara56300Pakistan Department of Statistics and Computer Science University of Veterinary and Animal SciencesLahorePunjab54000Pakistan School of Biochemistry and Biotechnology University of the PunjabLahore54000Pakistan Department of Computer Science Bahria UniversityLahore CampusLahore54600Pakistan

Around one in eight women will be diagnosed with breast cancer at some *** patient outcomes necessitate both early detection and an accurate *** images are routinely utilized in the process of diagnosing breast *** proposed in recent research only focus on classifying breast cancer on specific magnification *** study has focused on using a combined dataset with multiple magnification levels to classify breast cancer.A strategy for detecting breast cancer is provided in the context of this *** image texture data is used with the wavelet transform in this *** proposed method comprises converting histopathological images from Red Green Blue(RGB)to Chrominance of Blue and Chrominance of Red(YCBCR),utilizing a wavelet transform to extract texture information,and classifying the images with Extreme Gradient Boosting(XGBOOST).Furthermore,SMOTE has been used for resampling as the dataset has imbalanced *** suggested method is evaluated using 10-fold cross-validation and achieves an accuracy of 99.27%on the BreakHis 1.040X dataset,98.95%on the BreakHis 1.0100X dataset,98.92%on the BreakHis 1.0200X dataset,98.78%on the BreakHis 1.0400X dataset,and 98.80%on the combined *** findings of this study imply that improved breast cancer detection rates and patient outcomes can be achieved by combining wavelet transformation with textural signals to detect breast cancer in histopathology images.

关键词： Benign and malignant color conversion wavelet domain texture features xgboost

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Computational Fluid Dynamics(CFD) Modeling of Heat Transfer in a Polymeric Membrane using Finite Volume Method

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Journal of Thermal Science 2016年第6期25卷 564-570页

作者： muhammad Ahsan arshad Hussain School of Chemical and Materials Engineering(SCME) National University of Sciences and Technology(NUST)

The efficiency,robustness and reliability of recent numerical methods for finding solutions to flow problems have given rise to the implementation of computational fluid dynamics(CFD) as a broadly used analysis method for engineering problems like membrane separation *** CFD modeling in this study observes steady and unsteady(transient) heat flux and temperature profiles in a polymeric(cellulose acetate) *** study is novel due to the implementation of user defined scalar(UDS) diffusion equation by using user-defined functions(UDFs) infinite volume method(FVM).Some details of the FVM used by the solver are carefully discussed when implementing terms in the governing equation and boundary conditions(BC).The contours of temperature due to high-temperature gradient are reported for steady and unsteady problems.

关键词： unsteady solver scalar polymeric Membrane robustness governing carefully details discretization

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Two Layer Symmetric Cryptography Algorithm for Protecting Data from Attacks

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Computers, Materials & Continua 2023年第2期74卷 2625-2640页

作者： muhammad nadeem Ali arshad Saman Riaz Syeda Wajiha Zahra Shahab SBand Amir Mosavi Department of Computer Science Abasyn UniversityIslamabad44000Pakistan Department of Computer Science National University of TechnologyIslamabad44000Pakistan Future Technology Research Center National Yunlin University of Science and TechnologyDouliuYunlin64002Taiwan Institute of Information Society University of Public ServiceBudapest1083Hungary John Von Neumann Faculty of Informatics Obuda UniversityBudapestHungary Institute of Information Engineering Automation and MathilticsSlovak University of Technology in BratislavaSlovakia

Many organizations have insisted on protecting the cloud server from the outside,although the risks of attacking the cloud server are mostly from the *** are many algorithms designed to protect the cloud server from attacks that have been able to protect the cloud server ***,the attackers have designed even better mechanisms to break these security *** cryptography is the best data protection algorithm that exchanges data between authentic *** this article,one symmetric cryptography algorithm will be designed to secure cloud server data,used to send and receive cloud server data securely.A double encryption algorithm will be implemented to send data in a secure ***,the XOR function will be applied to plain text,and then salt technique will be ***,a reversing mechanism will be implemented on that data to provide more data *** decrypt data,the cipher text will be reversed,salt will be removed,andXORwill be *** the end of the paper,the proposed algorithm will be compared with other algorithms,and it will conclude how much better the existing algorithm is than other algorithms.

关键词： Cryptography symmetric algorithm encryption decryption cipher text cloud security asymmetric algorithm

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Preventing Cloud Network from Spamming Attacks Using Cloudflare and KNN

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Computers, Materials & Continua 2023年第2期74卷 2641-2659页

作者： muhammad nadeem Ali arshad Saman Riaz SyedaWajiha Zahra muhammad Rashid Shahab S.Band Amir Mosavi Department of Computer Science Abasyn UniversityIslamabad44000Pakistan Department of Computer Science National University of TechnologyIslamabad44000Pakistan Future Technology Research Center National Yunlin University of Science and TechnologyDouliuYunlin64002Taiwan Institute of Information Society University of Public ServiceBudapest1083Hungary John von Neumann Faculty of Informatics Obuda UniversityBudapestHungary Institute of Information Engineering Automation and MathematicsSlovak University of Technology in BratislavaSlovakia

Cloud computing is one of the most attractive and cost-saving models,which provides online services to *** computing allows the user to access data directly from any *** nowadays,cloud security is one of the biggest issues that *** types of malware are wreaking havoc on the *** on the cloud server are happening from both internal and external *** paper has developed a tool to prevent the cloud server from spamming *** an attacker attempts to use different spamming techniques on a cloud server,the attacker will be intercepted through two effective techniques:Cloudflare and K-nearest neighbors(KNN)*** will block those IP addresses that the attacker will use and prevent spamming ***,the KNN classifiers will determine which area the spammer belongs *** the end of the article,various prevention techniques for securing cloud servers will be discussed,a comparison will be made with different papers,a conclusion will be drawn based on different results.

关键词： Intrusion prevention system spamming KNN classification spam cyber security botnet

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Application of Micronutrients in Rice-Wheat Cropping System of South Asia

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Rice science 2019年第6期26卷 356-371页

作者： Faisal nadeem muhammad FAROOQ Department of Agronomy University of Agriculture Faisalabad 38040 Pakistan Department of Crop Science College of Agricultural and Marine Sciences Sultan Qaboos University Al-Khoudh 123 Oman

Rice-wheat cropping system (RWCS) is one of the most important cropping systems in South Asia. However, sustainability of this system is under threat owing to several factors, of which deficiency of micronutrients particularly zinc (Zn), boron (B) and manganese (Mn) is one of the major problems. Continuous rotation of rice and wheat, imbalanced fertilizer use and little/no use of micronutrient-enriched fertilizers induce deficiencies of Zn, B and Mn in the RWCS of South Asia. Here we review that (i) imbalanced fertilizer use and organic matter depletion deteriorate soil structure resulting in low efficiency of applied macro- and micro-nutrients in RWCS.(ii) The micronutrients (Zn, B and Mn) are essentially involved in metabolism of rice and wheat plants, including chlorophyll synthesis, photosynthesis, enzyme activation and membrane integrity.(iii) Availability and uptake of Zn, B and Mn from rhizosphere depend on the physico-chemical soil properties (which differ under aerobic and anaerobic conditions) including soil pH, soil organic matter, soil moisture and interaction of these micronutrients with other nutrients.(iv) Plant ability to uptake and utilize the nutrients is affected by several plant factors such as root architecture, root hairs, transport kinetics parameter and root exudates.(v) Crop management and application of these microelements can help correct the micronutrients deficiency and enhance their grain concentration.

关键词： micronutrient deficiency rice-wheat cropping system agronomic approach

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Efect of Thermal Annealing on the Physical Properties of Zn_(1-x)Cu_xSe Thin Films Deposited by Close Spaced Sublimation Technique

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Acta Metallurgica Sinica(English Letters) 2013年第6期26卷 699-706页

作者： muhammad Arslan Riaz muhammad arshad Mahmood Rashad Rasheed Department of Applied Physics Federal Urdu University of ArtsSciences and Technology National Institute of Lasers and Optronics

Thin films of Zn1-xCuxSe （x= 0.00, 0.05, 0.10, 0.15, 0.20） were grown on glass substrates by closed space sublimation technique. The deposited films were annealed at 200 ~C and 400 ~C in air for 1 h. The annealed samples have been investigated through Rutherford backscattering spectroscopy （RBS）, X-ray diffraction （XRD）, spectroscopic ellipsometer, spectrophotometer and Raman spectroscopy. Through RBS, the composition of the films was calculated and compared with the initial concentration. Structural characteriza- tion including crystal structure, crystal orientation, lattice parameter, grain size, strain and dislocation density were carried out using XRD data. From XRD spectra it was revealed that the as-deposited and annealed films were polycrystalline in nature with zinc-blende structure. However, the crystallinity and the grain size were improved with the increase of annealing temperature. According to Raman spectroscopy, it was observed that as deposited and annealed samples have the same characteristic vibrational modes of ZnSe at low and high frequency optical phonon modes while another mode was observed for 400 ℃ annealed samples at 745 cm-1. Spectroscopic ellipsometer has been used to found annealing effect on the optical properties of ZnSe. The band gap energy has been determined using transmission spectra. It was found that the band gap energy of the film increased with the increase of annealing temperature.

关键词： Closed space sublimation Annealing effect Structural Transmission Band gap Spectroscopic ellipsometer Raman spectroscopy

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