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Chinese Journal of Structural Chemistry 2015年第1期34卷 26-32页

作者： MUHAMMAD Naeem Ahmed KHAWAJA Ansar Yasin MUHAMMAD Nawaz Tahir ifzan arshad MURTAZA Madni Department of Chemistry The University of Azad Jammu and Kashmir University of Sargodha Department of Physics Department of Chemistry Quaid-i-Azam University

Two new 1,4-disubstituted 1,2,3-triazoles-4-carboxylates were synthesized via click reaction. Compound 1a was synthesized by the interaction of 6-nitro-tetrazolo[1.5-a]-pyridine with ethyl propynoate at room temperature in the presence of Cu（OAc）2 as a catalyst and THF as solvent. Compound 1b was also synthesized by the same manner except that tert-butyl propionate, instead of ethyl propynoate, was used. The compounds were characterized by IR, 1H-NMR, 13C-NMR and single-crystal X-ray diffraction analysis. Compound 1a（C10H9N5O4） crystallizes in the triclinic system, space group P1 with a = 5.0894（9）, b = 8.9834（13）, c = 13.089（2）？, α= 83.041（7）, β= 80.256（7）, γ=87.296（8）°, V = 585.24（16）？3, Z = 2, Mr = 263.22, crystal size（mm） = 0.37 × 0.20 ×0.18,（I 〉 2σ（I）） = 8557, 2493, 1229, Rint = 0.057. Compound 1b（C12H13N5O4） crystallizes in the monoclinic system, space group P21/c with a = 6.8854（5）, b = 21.783（2）, c = 9.3986（8）？,β = 93.239（4）°, V = 1407.4（2）？3, Z = 4, Mr = 291.27, crystal size（mm） = 0.38 × 0.22 × 0.20,（I 〉 2σ（I）） = 11842, 3172, 1866, Rint = 0.047. Antimicrobial assay results showed that the title compounds display excellent activities to different bacterial and fungal strains.

关键词： click reaction triazoles crystal structure antimicrobial activity

Crystal Structure Analysis of 1-Hydroxy-3,5-dimethoxy-9H-xanthen-9-one Isolated from Ajuga bracteosa Root Extract and Its Biological Studies

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Chinese Journal of Structural Chemistry 2019年第9期38卷 1519-1529页

作者： AKHTER Kulsoom AHMED Muhammed Naeem GHOUS Tahseen RASHEED Basharat TAHIR Muhammad Nawaz arshad ifzan Department of Chemistry The University of Azad Jammu and KashmirMuzaffarabad13100Pakistan Department of Chemistry Mirpur University of Science and Technology(MUST)Mirpur-10250Azad Jammu and KashmirPakistan Department of Physics University of SargodhaSargodhaPakistan Department of Chemistry Quaid-i-Azam UniversityIslamabadPakistan

The structure of 1-hydroxy-3,5-dimethoxy-9 H-xanthen-9-one isolated from chloroform extract of Ajuga bracteosa root was analyzed by single-crystal X-ray diffraction. DPPH(1,1-diphenyl-2-picryl hydrazyl), ABTS(2,2?-azino-bis-3-ethylbenzothiazoline-6-sulfonic acid) radical scavenging activities(RSA) and Fe2+ chelating activities were carried out to determine the antioxidant potential of the compound. RSA values for the compound were 96%, 96% and 96% for all the three activities respectively at maximum concentration of the compound(100 μ gmL-1) with the IC50 values of 3.40, 4.86 and 0.10(μ gmL-1). Antidiabetic activities including antiglycation and α-glucosidase inhibition were also performed where the antiglycation activity was performed using two techniques including spectrofluorometric as well as spectrophotometric technique. Spectrofluorometric technique provided 97% antiglycation potential while 92% antiglycation potential was observed by spectrophotometric technique for the isolated compound. The compound at a concentration of 10 μ gmL-1 exhibited 31% α-glucosidase inhibitory potential with IC50 of 15.56 μ gmL-1. Antimicrobial activity data showed that the compound was active against all the studied pathogenic bacteria.

关键词： crystal structure radical scavenging activity antidiabetic activity C–H···π interactions

Molecular Structure of (1-Benzyl-4-phenyl-1H-1,2,3-triazol-5-yl)(4-bromophenyl) methanone: A Combined Experimental and Theoretical Study

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Chinese Journal of Structural Chemistry 2014年第12期33卷 1749-1756页

作者： MUHAMMAD Naeem Ahmed ifzan arshad WANG Bo SHAHID Hameed BILAL Ahmad Khan KHAWAJA Ansar Yasin MUHAMMAD Moazzam Naseer Department of Chemistry The University of Azad Jammu and Kashmir Muzaffarabad 13100 Pakistan Department of Chemistry Quaid-i-Azam University Islamabad 45320 Pakistan Department of Chemistry Tsinghua University

One-pot three component reaction was used to synthesize 1,4,5-trisubstituted 1,2,3-triazole(A) from the corresponding acid chloride, benzyl azide and 1-copper(I) phenylethyne. The molecular structure was determined by single-crystal X-ray analysis. The compound crystallizes in the orthorhombic space group Pbca, a = 14.9815(14), b = 9.6496(10), c = 25.528(2) A, Z = 8. Furthermore, crystal packing demonstrated a molecular wall-like structure based on supramolecular chains of A, stabilized by CH···O, CH···Br, N···C and CH···π interactions. Molecular geometry in the ground state has been determined by density functional theory(DFT) by B3LYP/6-311G* basis set and compared with the experimental data. The computed vibrational frequencies are compared with the experimental FT-IR data and frontier molecular orbital analyses were performed at the same level of theory. Theoretical parameters are in good agreement with the corresponding X-ray diffraction values.

关键词： synthesis 1,2,3-triazole crystal structure molecular packing optimization

Synthesis, Crystal Structure and Antimicrobial Activity of Ethyl 2-(1-cyclohexyl-4-phenyl-1H-1,2,3-triazol-5-yl)-2-oxoacetate

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Chinese Journal of Structural Chemistry 2014年第11期33卷 1666-1672页

作者： MUHAMMAD Naeem Ahmed SHAHID Hameed KHAWAJA Ansar Yasin ifzan arshad IHSAN-ul-Haq SAFEENA Zafar MUHAMMAD Nawaz Tahir Department of Chemistry The University of Azad Jammu and Kashmir Department of Chemistry Quaid-i-Azam University Department of Pharmacy Faculty of Biological SciencesQuaid-i-Azam University University of Sargodha Department of Physics

A novel 1,4,5-trisubstituted 1,2,3-triazole（C18H21N3O3） was synthesized by a one-pot three component reaction of 1-azidocyclohexane, 1-copper（I） phenylethyne and ethoxalyl chloride at room temperature. The molecular structure was determined by single-crystal X-ray analysis. The compound crystallizes in the monoclinic system, space group P21/n with a = 12.8167（9）, b = 8.0966（6）, c = 16.7079（9） A, β = 98.716（2）°, Z = 4 and V = 1713.8（2）. In the crystal, the molecules are related by inversion and paired into dimers via C–H…O and C–O…C interactions involving（oxo） acetate groups. Furthermore, X-ray analysis results are compared with the optimized structure computed by using B3 LYP method with 6-311 G basis set. The calculated results showed that optimized geometry can well reproduce the crystal structure parameters. The bioassay results indicate that the compound has good antibacterial and antifungal activities.

关键词： click chemistry triazole cyclohexyl oxoacetate XRD antimicrobial

One-pot Synthesis,Characterization and Crystal Structure Determination of Novel 1,4,5-Trisubstituted 1,2,3-Triazole with Two Conformational Isomers:1-Benzyl-5-((4-methoxyphenyl)ethynyl)-4-phenyl-1H-1,2,3-triazole

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Chinese Journal of Structural Chemistry 2016年第1期35卷 55-60页

作者： AHMED Muhammad Naeem YASIN Khawaja Ansar KHAN Bilal Ahmad RIAZ Muhammad SADIQ-UR-REHMAN LO Kong Mun NASEER Muhammad Moazzam arshad ifzan IRSHAD Muhammad Department of Chemistry The University of Azad Jammu and Kashmir Department of Chemistry University of Malaya Department of Chemistry Quaid-i-Azam University Department of Chemistry University of Poonch Rawalakot Azad Kashmir

The title compound l-benzyl-5-（（4-methoxyphenyl）ethynyl）-4-phenyl-1H-1,2,3-triazole（C24H19N3O） was designed and synthesized using one-pot strategy and structural characterization was done by single-crystal X-ray diffraction,NMR,IR and *** compound was crystallized out from an ethanolic solution in triclinic system,space group P1 with a =9.9038（9）,b = 10.2928（9）,c = 18.8715（19）A°,α = 103.541（6）,β = 90.507（7）,γ = 97.157（7）°,V =1854.2（3） A°3,Z = 4,crystal size（mm） = 0.25 × 0.1 × 0.1 and R（int） = *** asymmetric unit contains two independent *** crystal structure of the title compound is stabilized by intramolecular interactions of types C-H…N and C-H…***,X-ray analysis reveals obvious C-H…π,π-π stacking interactions between two adjacent aromatic ring planes.

关键词： click chemistry trisubstituted triazole alkyne crystal structure C–H…π interactions

Evaluation of soil loss severity and ecological restoration approach for sustainable agriculture in the Hindu Kush, Karakoram and Himalaya region

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Journal of Mountain Science 2024年第5期21卷 1509-1521页

作者： arshad ASHRAF Imran AHMAD Climate Energy and Water Research InstituteNational Agricultural Research Centre(NARC)Islamabad 44000Pakistan

Soil erosion has resulted in removal of the topsoils containing fine soil particles and plant nutrients, causing decrease in soil fertility in the Hindu Kush, Karakoram and Himalaya(HKH) region. The existing production of cereal crop grains has been reduced to one third of the potential crop grains production owing to land degradation and poor farming practices. It is necessary to assess risk of soil loss and identify appropriate controlling measures to address issues of low agriculture productivity and water insecurity in the region. In the present study, severity of soil loss was predicted using Revised Universal Loss Equation(RUSLE) and ecological measures were identified for sustainable mountain agriculture in the HKH region of Upper Indus Basin, Pakistan. Overall 62.6% area was found to have very low risk of soil loss, i.e., 100 t/(ha·yr) in about 6.8% and 7.4% areas respectively. The mean rate of soil loss was about 41.9 t/(ha·yr) in the Hindu Kush, 31.1 t/(ha·yr) in the Himalayas, 18.8 t/(ha·yr) in the Karakoram and overall 29.7 t/(ha·yr) in the three HKH ranges. As such no considerable measures have been adopted by the communities for restoration of the degraded areas except raising fruit/farm trees and supporting limited social forestry for their livelihoods. The slopes cleared for cultivation and susceptible to erosion may be stabilized through sowing/planting of multi-purpose plant species and formation of proper bench terraces. The conservation of forest ecosystem and pastures at higher elevations would help in reducing overland water flow, risk of flash flood hazard and minimizing sediment loads in the downstream. It is essential to adopt site-specific resource conservation techniques and restore possible ecosystem health for sustainable agriculture and economic developm

关键词： Climate change Erodibility Indus basin Land degradation Slope stabilization

ROBO-SPOT:Detecting Robocalls by Understanding User Engagement and Connectivity Graph

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Big Data Mining and Analytics 2024年第2期7卷 340-356页

作者： Muhammad Ajmal Azad Junaid arshad Farhan Riaz College of Comnputer Science Birmingham City UniversityBirminghamB55JUUK School of Computer Science University of LincolnLincolnLN67TSUK

Robo or unsolicited calls have become a persistent issue in telecommunication networks,posing significant challenges to individuals,businesses,and regulatory *** calls not only trick users into disclosing their private and financial information,but also affect their productivity through unwanted phone ringing.A proactive approach to identify and block such unsolicited calls is essential to protect users and service providers from potential ***,this paper proposes a solution to identify robo-callers in the telephony network utilising a set of novel features to evaluate the trustworthiness of callers in a *** trust score of the callers is then used along with machine learning models to classify them as legitimate or *** use a large anonymized dataset(call detailed records)from a large telecommunication provider containing more than 1 billion records collected over 10 *** have conducted extensive evaluation demonstrating that the proposed approach achieves high accuracy and detection rate whilst minimizing the error ***,the proposed features when used collectively achieve a true-positive rate of around 97%with a false-positive rate of less than 0.01%.

关键词： social network analysis reputation unwanted calls robo-callers telephone network Spam Over Internet Technology(SPIT)

Aberrant adult neurogenesis in intractable epilepsy:can GABAergic progenitor transplantation normalize this process?

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Neural Regeneration Research 2024年第7期19卷 1419-1420页

作者： Muhammad N.arshad Janice R.Naegele Department of Biology Wesleyan UniversityMiddletownCTUSA Department of Neuroscience Tufts University School of MedicineBostonMAUSA

Temporal lobe epilepsy(TLE) is a common type of focal epilepsy characterized by seizure foci within the temporal *** surgical resection of the foci is an established and effective approach for controlling seizures,both temporal lobes cannot be removed,due to their prominent roles in learning and ***,seizures induce changes to the temporal lobes that contribute to hyperexcitability,including mossy fiber sprouting,astrogliosis.

关键词： epilepsy progenitor seizures

Predicting Age and Gender in Author Profiling: A Multi-Feature Exploration

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Computers, Materials & Continua 2024年第5期79卷 3333-3353页

作者： Aiman Muhammad arshad Bilal Khan Sadique Ahmad Muhammad Asim Department of Computer Science City University of Science and Information TechnologyPeshawar25000Pakistan EIAS:Data Science and Blockchain Laboratory College of Computer and Information SciencesPrince Sultan UniversityRiyadh11586Saudi Arabia School of Computer Science and Technology Guangdong University of TechnologyGuangzhou510006China

Author Profiling (AP) is a subsection of digital forensics that focuses on the detection of the author’s personalinformation, such as age, gender, occupation, and education, based on various linguistic features, e.g., stylistic,semantic, and syntactic. The importance of AP lies in various fields, including forensics, security, medicine, andmarketing. In previous studies, many works have been done using different languages, e.g., English, Arabic, French,***, the research on RomanUrdu is not up to the ***, this study focuses on detecting the author’sage and gender based on Roman Urdu text messages. The dataset used in this study is Fire’18-MaponSMS. Thisstudy proposed an ensemble model based on AdaBoostM1 and Random Forest (AMBRF) for AP using multiplelinguistic features that are stylistic, character-based, word-based, and sentence-based. The proposed model iscontrasted with several of the well-known models fromthe literature, including J48-Decision Tree (J48),Na飗e Bays(NB), K Nearest Neighbor (KNN), and Composite Hypercube on Random Projection (CHIRP), NB-Updatable,RF, and AdaboostM1. The overall outcome shows the better performance of the proposed AdaboostM1 withRandom Forest (ABMRF) with an accuracy of 54.2857% for age prediction and 71.1429% for gender predictioncalculated on stylistic features. Regarding word-based features, age and gender were considered in 50.5714% and60%, respectively. On the other hand, KNN and CHIRP show the weakest performance using all the linguisticfeatures for age and gender prediction.

关键词： Digital forensics author profiling for security AdaBoostM1 random forest ensemble learning

A Compact Difference Scheme for Time-Space Fractional Nonlinear Diffusion-Wave Equations with Initial Singularity

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Advances in Applied Mathematics and Mechanics 2024年第1期16卷 146-163页

作者： Emadidin Gahalla Mohmed Elmahdi Sadia arshad Jianfei Huang College of Mathematical Sciences Yangzhou UniversityYangzhouJiangsu 225002China Faculty of Education University of KhartoumKhartoum P.O.Box 321Sudan COMSATS University Islamabad Lahore CampusPakistan

In this paper,we present a linearized compact difference scheme for onedimensional time-space fractional nonlinear diffusion-wave equations with initial boundary value *** initial singularity of the solution is considered,which often generates a singular source and increases the difficulty of numerically solving the *** Crank-Nicolson technique,combined with the midpoint formula and the second-order convolution quadrature formula,is used for the time *** increase the spatial accuracy,a fourth-order compact difference approximation,which is constructed by two compact difference operators,is adopted for spatial ***,the unconditional stability and convergence of the proposed scheme are strictly established with superlinear convergence accuracy in time and fourth-order accuracy in ***,numerical experiments are given to support our theoretical results.

关键词： Fractional nonlinear diffusion-wave equations finite difference method fourth-order compact operator stability convergence