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Continuous chemical redistribution following amorphous-to-crystalline structural ordering in a Zr-Cu-Al bulk metallic glass

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Journal of Materials Science & Technology 2022年第6期101卷 285-293页

作者： Xuelian Wu Si Lan Xiyang Li Ming Yang Zhenduo Wu Xiaoya Wei Haiyan He muhammad naeem Jie Zhou Zhaoping Lu Elliot Paul Gilbert Dong Ma Xun-Li Wang Department of Physics City University of Hong KongHong KongChina Herbert Gleiter Institute of Nanoscience School of Materials Science and EngineeringNanjing University of Science and TechnologyNanjing 210094China Beijing National Laboratory for Condensed Matter Physics Institute of PhysicsChinese Academy of SciencesBeijing 100190China Quantum Matter Institute University of British ColumbiaVancouverBritish Columbia V6T 1Z4Canada Neutron Sciences Platform Songshan Lake Materials LaboratoryDongguan 523808China Center for Neutron Scattering and Applied Physics City University of Hong Kong Dongguan Research InstituteDongguan 523000China State Key Laboratory for Advanced Metals and Materials University of Science and Technology BeijingBeijing 100083China Australian Centre for Neutron Scattering Australian Nuclear Science and Technology OrganisationLucas HeightsNew South Wales 2234Australia City University of Hong Kong Shenzhen Research Institute Shenzhen 518057China

Bulk metallic glasses(BMGs)are thermodynamically *** such,crystallization occurs when a BMG is thermally annealed at a temperature above the glass transition *** extensive studies have been performed on the crystallization kinetics of BMGs,most of them have focused on the amorphous-to-crystalline structural ordering,and little attention has been paid to chemical distribution and its relationship with the structural ordering during the crystallization *** this paper,a new approach,with simultaneous differential scanning calorimetry(DSC)and small angle neutron scatter-ing(SANS)measurements,was applied to study in situ the crystallization of a Zr_(45.5)Cu_(45.5)Al_(9)BMG upon isothermal annealing at a temperature in the supercooled liquid *** analysis of the DSC and SANS data showed that the structural evolution during isothermal annealing could be classified into three stages:(Ⅰ)incubation;(Ⅱ)amorphous-to-crystalline structural ordering;(Ⅲ)continuous chemical *** finding was validated by composition analysis with atom probe tomography(APT),which further identified a transition region formed by expelling Al into the *** transition re-gion,with a composition of(Cu,Al)_(50)Zr_(50),served as an intermediate step facilitating the formation of a thermodynamically stable crystalline phase with a composition of(Cu,Al)_(10)Zr_(7).

关键词： Bulk metallic glass Crystallization In situ Continuous chemical redistribution Transition region

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Reprogramming Mycobacterium tuberculosis CRISPR System for Gene Editing and Genomewide RNA Interference Screening

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Genomics, Proteomics & Bioinformatics 2022年第6期20卷 1180-1196页

作者： Khaista Rahman muhammad Jamal Xi Chen Wei Zhou Bin Yang Yanyan Zou Weize Xu Yingying Lei Chengchao Wu Xiaojian Cao Rohit Tyagi muhammad Ahsan naeem Da Lin Zeshan Habib Nan Peng Zhen F.Fu Gang Cao State Key Laboratory of Agricultural Microbiology Huazhong Agricultural UniversityWuhan 430070China College of Veterinary Medicine Huazhong Agricultural UniversityWuhan 430070China Bio-Medical Center Huazhong Agricultural UniversityWuhan 430070China Key Laboratory of Preventive Veterinary Medicine in Hubei Province the Cooperative Innovation Center for Sustainable Pig ProductionWuhan 430070China

Mycobacterium tuberculosis is the causative agent of tuberculosis(TB), which is still the leading cause of mortality from a single infectious disease worldwide. The development of novel anti-TB drugs and vaccines is severely hampered by the complicated and time-consuming genetic manipulation techniques for M. tuberculosis. Here, we harnessed an endogenous type Ⅲ-A CRISPR/Cas10 system of M. tuberculosis for efficient gene editing and RNA interference(RNAi).This simple and easy method only needs to transform a single mini-CRISPR array plasmid, thus avoiding the introduction of exogenous protein and minimizing proteotoxicity. We demonstrated that M. tuberculosis genes can be efficiently and specifically knocked in/out by this system as confirmed by DNA high-throughput sequencing. This system was further applied to single-and multiple-gene RNAi. Moreover, we successfully performed genome-wide RNAi screening to identify M. tuberculosis genes regulating in vitro and intracellular growth. This system can be extensively used for exploring the functional genomics of M. tuberculosis and facilitate the development of novel anti-TB drugs and vaccines.

关键词： Mycobacterium tuberculosis Type III-A CRISPR system Gene editing Gene interference Genome-wide RNAi screening

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Strong interfacial charge transfer between hausmannite manganese oxide and alumina for efficient photocatalysis

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Chinese Journal of Chemical Engineering 2021年第5期34卷 147-159页

作者： Aisha Kanwal Shamaila Sajjad Sajjad Ahmed Khan Leghari muhammad naeem Khan International Islamic University H-10 IslamabadPakistan Pakistan Institute of Engineering and Applied Sciences Islamabad 44000Pakistan Department of Chemistry Government College of ScienceLahorePakistan

Well crystalline manganese oxide(Mn_(3)O_(4))nanoparticles anchored on gamma alumina(γ-Al_(2)O_(3))have been successfully tailored via a proficient and cost effective chemical process as an efficient material for photo *** indicated the composite formation ofγ-Al_(2)O_(3) and hausmannite structure of Mn_(3)O_(4).SEM and TEM revealed that hetero structure of Mn_(3)O_(4)/γ-Al_(2)O_(3) exhibits an amalgam of aggregated nanoparticles and *** demonstrated the chemical states of binary *** band gap tuning has been performed withγ-Al_(2)O_(3) nanoparticles by assimilating hausmannite Mn_(3)O_(4) particles into flower like microstructure of Al_(2)O_(3).The photoluminescence spectra affirmed the enhancement in charge separation in Mn_(3)O_(4)/γ-Al_(2)O_(3) binary hybrid *** band gap becomes narrow with the increase in concentrations of Mn_(3)O_(4).The narrowing of band gap is concorded with crystalline domains of primary aggregated *** elucidate the mechanism of the photocatalytic activity linear sweep voltammetry was *** results showed that Mn_(3)O_(4)/γ-Al_(2)O_(3) nanocomposite revealed the enhancement in current density as compared to pureγ-Al_(2)O_(3) which confirmed the electron transfer from Mn_(3)O_(4) toγ-Al_(2)O_(3) through the interfacial potential gradient in conduction *** optimum concentration of 6.0%Mn_(3)O_(4)/γ-Al_(2)O_(3) for hybrid structure showed an excellent photocatalytic activity under visible light due to narrow band gap *** degree distribution of Mn_(3)O_(4) nano architects overlying onγ-Al_(2)O_(3) induces a significant synergic effect betweenγ-Al_(2)O_(3) and hausmannite phase of manganese oxide(Mn_(3)O_(4)).This strong interfacial contact betweenγ-Al_(2)O_(3) and Mn_(3)O_(4) endures the quick transfer of photo generated charge carriers across interface.

关键词： Hausmannite Mn_(3)O_(4) Alumina Band gap tuning Interfacial charge transfer Nanomaterials Catalysis

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Vibrations of FGM thin cylindrical shells with exponential volume fraction law

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Applied Mathematics and Mechanics(English Edition) 2009年第5期30卷 607-615页

作者： Abdul Ghafar Shah Tahir Mahmood muhammad Nawaz naeem Department of Mathematics The Islamia University of Bahawalpur Department of Mathematics Government College University

In this paper, the influence of an exponential volume fraction law on the vibration frequencies of thin functionally graded cylindrical shells is studied. Material properties in the shell thickness direction are graded in accordance with the exponential law. Expressions for the strain-displacement and curvature-displacement relationships are taken from Love＇s thin shell theory. The Rayleigh-Ritz approach is used to derive the shell eigenfrequency equation. Axial modal dependence is assumed in the characteristic beam functions. Natural frequencies of the shells are observed to be dependent on the constituent volume fractions. The results are compared with those available in the literature for the validity of the present methodology.

关键词： functionally graded material (FGM) vibration cylindrical shell Rayleigh- Ritz method exponential volume fraction law

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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

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Epidemiological Analysis of the Coronavirus Disease Outbreak with Random Effects

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Computers, Materials & Continua 2021年第6期67卷 3215-3227页

作者： muhammad Farman Aqeel Ahmad Ali Akgül muhammad Umer Saleem muhammad naeem Dumitru Baleanu Department of Mathematics and Statistics University of LahorePakistan Department of Mathematics Faculty of Art and ScienceSiirt UniversitySiirt56100Turkey Department of Mathematics University of EducationLahorePakistan Department of Economics and Business Administration University of EducationLahorePakistan Department of Mathematics Cankaya UniversityBalgat06530Turkey Institute of Space Sciences Magurele-BucharestR76900Romania Department of Medical Research China Medical UniversityTaichung40402Taiwan

Today,coronavirus appears as a serious challenge to the whole *** data of coronavirus is collected through media and web sources for the purpose of *** data on COVID-19 are available daily,yet information about the biological aspects of SARS-CoV-2 and epidemiological characteristics of COVID-19 remains limited,and uncertainty remains around nearly all its parameters’*** research provides the scientic and public health communities better resources,knowledge,and tools to improve their ability to control the infectious *** the publicly available data on the ongoing pandemic,the present study investigates the incubation period and other time intervals that govern the epidemiological dynamics of the COVID-19 *** of the testing hypotheses for different countries with a 95%level of condence,and descriptive statistics have been calculated to analyze in which region will COVID-19 fall according to the tested hypothesized mean of different *** results will be helpful in decision making as well as in further mathematical analysis and control *** tools are used to investigate this pandemic,which will be useful for further *** testing of the hypothesis is done for the differences in various effects including standard *** in states’variables are observed over *** rapid outbreak of coronavirus can be stopped by reducing its *** should maintain safe distance and follow precautionary measures regarding COVID-19 transmission.

关键词： Covid-19 infectious disease statistical analysis p-value epidemiology hypothesis

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用人工神经网络混合元启发式优化技术分析不可压缩黏性流体在收敛和发散通道中的流动:一种智能方法

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Journal of Central South University 2023年第12期30卷 4149-4167页

作者： ASLAM muhammad naeem RIAZ Arshad SHAUKAT Nadeem ALI Shahzad AKRAM Safia BHATTI M.M. Department of Physics and Applied Mathematics(DPAM) Pakistan Institute of Engineering&Applied SciencesNilore 45650IslamabadPakistan Center for Mathematical Sciences(CMS) Pakistan Institute of Engineering&Applied SciencesNilore 45650IslamabadPakistan Department of Mathematics Division of Science and TechnologyUniversity of EducationLahore 54770Pakistan School of Mathematics Minhaj UniversityLahorePakistan MCS National University of Sciences and TechnologyIslamabadPakistan College of Mathematics and Systems Science Shandong University of Science and TechnologyQingdao 266590China

本文采用人工神经网络(ANN)与进化算法(特别是阿基米德优化算法(AOA)和水循环算法(WCA)相结合的方法)对非线性磁流体动力学(MHD)的Jeffery-Hamel问题,特别是收敛和发散通道中的拉伸/收缩问题进行了数值研究。这种组合技术被称为ANN-AOA-... 详细信息

本文采用人工神经网络(ANN)与进化算法(特别是阿基米德优化算法(AOA)和水循环算法(WCA)相结合的方法)对非线性磁流体动力学(MHD)的Jeffery-Hamel问题,特别是收敛和发散通道中的拉伸/收缩问题进行了数值研究。这种组合技术被称为ANN-AOA-WCA。将基于复杂非线性磁流体动力学Jeffery-Hamel问题的偏微分方程转化为速度和温度的非线性常微分方程系统,我们建立了基于人工神经网络的适应度函数来求解非线性微分问题。随后,采用了一种新的AOA和WCA结合方法(AOAWCA)来优化基于神经网络的适应度函数,并确定了神经网络的最优权值和偏差。为了证明提出混合方法的有效性和多功能性,探索了一系列雷诺数、通道角和可拉伸边界值的MHD模型,从而开发了两种不同的情况。ANN-AOA-WCA的数值结果与参考解(NDSOLVE)非常接近,NDSOLVE与ANNAOA-WCA的绝对误差约为3.35×10^(−8),对可拉伸收敛和发散通道的理解特别关键。此外,为了验证ANN-AOA-WCA技术,我们对150多个独立运行进行了统计分析,以获得适应度值。

关键词：人工神经网络阿基米德优化水循环算法拉伸/收缩表面收敛或发散通道

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A new auxiliary information based cumulative sum median control chart for location monitoring

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Frontiers of Information Technology & Electronic Engineering 2019年第4期20卷 554-570页

作者： shahid HUSSAIN Li-xin SONG Shabbir AHMAD muhammad RIAZ School of Mathematical Sciences Dalian University of Technology Department of Mathematics COMSATS Institute of Information Technology Department of Mathematics and Statistics King Fahad University of Petroleum and Minerals

Control charts are commonly used tools in statistical process control for the detection of shifts in process parameters. Shewhart-type charts are efficient for large shift values, whereas cumulative sum(CUSUM) charts are effective in detecting medium and small shifts. Control chart use commonly assumes that data are free of outliers and parameters are known or correctly estimated based on an in-control process. In practice, these assumptions are not often true because some processes occasionally have outliers. Monitoring the location parameter is usually based on mean charts, which are seriously affected by violations of these assumptions. In this paper we propose several CUSUM median control charts based on auxiliary variables, and offer comparisons with their corresponding mean control charts. To monitor the location parameter, we examined the performance of mean and median control charts in the presence and absence of outliers. Both symmetric and non-symmetric processes were studied to examine the properties of the proposed control charts to monitor the location parameter using CUSUM control charts. We used different run length measures to study in-control and out-of-control performances of CUSUM charts. Results revealed that our proposed control charts perform much better than the traditional charts in the presence of outliers. A real application of our study was provided using data on concrete compressive strength as it relates to the quality of cement manufacturing.

关键词： Average run length Auxiliary information CUSUM control charts Location parameter Median control charts

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Vibration analysis of damaged and undamaged steel structure systems: cantilever column and frame

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Earthquake Engineering and Engineering Vibration 2020年第3期19卷 725-737页

作者： muhammad Abuzar Khan Kareem Akhtar Naveed Ahmad Feroz Shah naeem Khattak Department of Mechanical Engineering University of Engineering&TechnologyPeshawar KPK 25120Pakistan Earthquake Engineering Center Department of Civil EngineeringUET PeshawarPakistan

This paper presents the experimental and numerical studies conducted on a steel column and a steel frame structure using free vibration *** effects of damages on structures were investigated,which were simulated by introducing multiple cracks at different locations in the experimental and numerical *** acceleration responses of the test models,were recorded through an accelerometer,and were used to calibrate the numerical models developed in finite element based *** frequencies of damaged and undamaged structures were compared and analyzed,to derive relationships for damaged and undamaged structures’frequencies in terms of crack *** was found that,due to the presence of cracks,the mechanical properties of a structure changes,whereby,the modal frequencies *** approximately linear trend was observed for the frequency decrease with the increase in crack depth,which was also confirmed by the numerical *** derived relationships were extended to further develop a mechanics-based damage scale for steel structures,to help facilitate structural health monitoring and screening of vulnerable structures.

关键词： steel column frame

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Optimization of Steel Bar Manufacturing Process Using Six Sigma

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Chinese Journal of Mechanical Engineering 2016年第2期29卷 332-341页

作者： naeem Khawar ULLAH Misbah TARIQ Adnan MAQSOOD shahid AKHTAR Rehman NAWAZ Rashid HUSSAIN Iftikhar Department of Industrial Engineering University of Engineering and Technology(UET) Peshawar

Optimization of a manufacturing process results in higher productivity and reduced wastes. Production parameters of a local steel bar manufacturing industry of Pakistan is optimized by using six Sigma-Define, measure, analyze, improve, and controlmethodology. Production data is collected and analyzed. After analysis, experimental design result is used to identify significant factors affecting process performance. The significant factors are controlled to optimized level using two-level factorial design method. A regression model is developed that helps in the estimation of response under multi variable input values. Model is tested, verified, and validated by using industrial data collected at a local steel bar manufacturing industry of Peshawar（Khyber Pakhtunkhwa, Pakistan）. The sigma level of the manufacturing process is improved to 4.01 from 3.58. The novelty of the research is the identification of the significant factors along with the optimum levels that affects the process yield, and the methodology to optimize the steel bar manufacturing process.

关键词： steel bar manufacturing industry six sigma yield sigma level design of experiments

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