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Chinese Journal of Chemical Engineering 2010年第6期18卷 979-987页

作者： ZHU Jie CUI Yu nawaz Zeeshan WANG Yao WEI Fei Beijing Key Laboratory of Green Chemical Reaction Engineering and Technology Department of Chemical Engineering Tsinghua University Beijing 100084 China

SAPO-34 zeolite is considered to be an effective catalyst for methanol or dimethyl ether conversion to olefins. In this study,we developed the in situ synthesis technology to prepare SAPO-34 zeolite in kaolin micro-spheres as a catalyst for fluidized methanol or dimethyl ether to olefins process. The silicoaluminophosphate zeolite was first time reported to be synthesized in kaolin microspheres. The SAPO-34 content of synthesized catalyst was about 22% as measured by three different quantitative methods(micropore area,X-ray fluorescence and energy dispersive spectroscopy element analysis) . Most of the SAPO-34 zeolites were in nanoscale size and distributed uniformly inside the spheres. The catalytic performance was evaluated in fixed bed and fluidized bed reactors. Compared with the conventional spray-dry catalyst,SAPO/kaolin catalyst showed superior catalytic activities,bet-ter olefin selectivities(up to 94%,exclusive coke) ,and very good hydrothermal stability. The in situ synthesis of SAPO-34 in kaolin microspheres is a facile and economically feasible way to prepare more effective catalyst for fluidized MTO/DTO(methanol to olefins/dimethyl ether to olefins) process.

关键词：流化床反应器甲醇制烯烃原位合成 SAPO 烯烃转化高岭土二甲醚分子筛

Dufour and Soret effects on MHD flow of viscous fluid between radially stretching sheets in porous medium

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Applied Mathematics and Mechanics(English Edition) 2012年第11期33卷 1403-1418页

作者： M. nawaz T. HAYAT A. ALSAEDI Department of Humanities and Sciences Institute of Space Technology Department of Mathematics Quaid-I-Azam University Department of Mathematics Faculty of Science King Abdulaziz University

The aim of this paper is two-dimensional magnetohydrodynamic viscous fluid bounded by infinite sheets to examine the Dufour and Soret effects on the （MHD） steady flow of an electrically conducting An incompressible viscous fluid fills the porous space. The mathematical analysis is performed in the presence of viscous dissipation, Joule heating, and a first-order chemical reaction. With suitable transformations, the governing partial differential equations through momentum, energy, and concentration laws are transformed into ordinary differential equations. The resulting equations are solved by the homotopy analysis method （HAM）. The convergence of the series solutions is ensured. The effects of the emerging parameters, the skin friction coefficient, the Nusselt number, and the Sherwood number are analyzed on the dimensionless velocities, temperature, and concentration fields.

关键词： magnetohydrodynamic (MHD) flow radial stretching Soret and Dufoureffects porous medium skin friction coefficient

Impact of polarization mode dispersion and nonlinearities on 2-channel DWDM chaotic communication systems

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Frontiers of Optoelectronics 2013年第3期6卷 312-317页

作者： Bushra nawaz Rameez ASIF Telecommunication Engineering Department University of Engineering &Tcchnology Taxila 47050 Pakistan

This paper has designed 2-channel dense wavelength division multiplexing （DWDM） chaotic sys- tem at the frequencies of 193.1 and 193,2THz, respec- tively. The optical chaotic signals were produced by using the semiconductor laser that is numerically modeled by employing laser rate equations. These two channels were multiplexed and then propagated through single mode optical fiber （SMF） of 80kin length with dispersion compensating fiber of 16 km length. Erbium doped fiber amplifier （EDFA） was used to compensate the power losses in the SMF. In lhis paper, we investigated the effects of polarization mode dispersion （PMD） and nonlinearities especially stimulated Raman scattering （SRS） on 2 channel DWDM chaotic communication system by varying the length of the SMF and value of differential group delay （DGD）.

关键词： chaos chaotic signal chaotic synchronization,dense wavelength division multiplexing (DWDM) chaoticcommunication polarization mode dispersion (PMD),stimulated Raman scattering (SRS)

Expression profiling of transgenes(Cry1Ac and Cry2A) in cotton genotypes under different genetic backgrounds

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Journal of Integrative Agriculture 2022年第10期21卷 2818-2832页

作者： Kashif NOOR Hafiza Masooma Naseer CHEEMA Asif Ali KHAN Rao Sohail ahmad KHAN Department of Plant Breeding and Genetics University of AgricultureFaisalabad 38040Pakistan Institute of Plant Breeding and Biotechnology Muhammad Nawaz Shareef University of AgricultureMultan 60000Pakistan Center of Agricultural Biochemistry and Biotechnology University of AgricultureFaisalabad 38040Pakistan

Transgenic cotton carrying the CrylAc gene has revolutionized insect pest control since its adoption,although the development of resistance in insect pests has reduced its *** 10 years of cultivating Bacillus thuringiensis(Bt)cotton with a single Cry1 Ac gene,growers are on the verge of adopting Bt cotton that carries the double gene(Cry1 Ac+Cry2 A)due to its better effectiveness against insect ***,the current study was designed to evaluate the role of each gene in the effectiveness of Bt cotton carrying the double *** expression levels of the Cry1 Ac and Cry2 A genes were evaluated in the leaves of 10 genotypes(2 parents and 8 Fhybrids)at 30 days after sowing(DAS),while samples of leaves,bolls and flowers were taken from the upper and lower canopies at 70 and 110 *** Fhybrids were developed through reciprocal crosses between two Bt(CKC-1,CKC-2)and two non-Bt(MNH-786,FH-942)*** differential expression of transgenes was evaluated through Enzyme Linked Immuno-Sorbent Assay(ELISA).The results showed that the MNH786 xCKC-1 hybrid had the highest concentrations of Cry1 Ac gene at30 DAS(3.08μg g^(-1))and 110 DAS(1.01μg g^(-1))in *** contrast,the CKC-2 xMNH-786 hybrid showed the lowest concentrations of Cry1 Ac gene at 30 DAS(2.30μg g^(-1))and 110 DAS(0.86μg g^(-1)).The Fhybrid FH-942×CKC-2 showed the highest concentrations of Cry2 A gene at 30 DAS(8.39μg g^(-1))and 110 DAS(7.74μg g^(-1))in leaves,while the CKC-1 xMNH-786 hybrid expressed the lowest concentrations of Cry2 A gene at 30 DAS(7.10μg g^(-1))and 110 DAS(8.31μg g^(-1)).A comparison between the two stages of plant growth showed that leaves had the highest concentrations at 30 DAS,whereas the lowest concentrations were observed at 110 DAS for both genes in *** the expression pattern was compared between various plant parts in genotype CKC-2,it was found that leaves had higher concentrations of Cry1 Ac(3.12μg g^(-1))and Cry2 A(8.31μg g^(-1))at 70 DAS,followed by bolls

关键词： transgenic cotton breeding transgene expression double gene insect resistance

Functional gastrointestinal disorders and gut-brain axis: What does the future hold?

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World Journal of Gastroenterology 2019年第5期25卷 552-566页

作者： Kashif Mukhtar Hasham nawaz Shahab Abid Centre of Excellence in Women and Child Health Aga Khan University Department of Medicine Section of Gastroenterology Aga Khan University

Despite their high prevalence, lack of understanding of the exact pathophysiology of the functional gastrointestinal disorders has restricted us to symptomatic diagnostic tools and therapies. Complex mechanisms underlying the disturbances in the bidirectional communication between the gastrointestinal tract and the brain have a vital role in the pathogenesis and are key to our understanding of the disease phenomenon. Although we have come a long way in our understanding of these complex disorders with the help of studies on animals especially rodents, there need to be more studies in humans, especially to identify the therapeutic targets. This review study looks at the anatomical features of the gut-brain axis in order to discuss the different factors and underlying molecular mechanisms that may have a role in the pathogenesis of functional gastrointestinal disorders. These molecules and their receptors can be targeted in future for further studies and possible therapeutic interventions. The article also discusses the potential role of artificial intelligence and machine learning and its possible role in our understanding of these scientifically challenging disorders.

关键词： Functional gastrointestinal disorders Idiopathic bowel syndrome Gut-brain axis Microbiome-gut-brain axis Machine learning Artificial intelligence

Glacier-Glacial Lake Interactions and Glacial Lake Development in the Central Himalaya,India(1994–2017)

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Journal of Earth Science 2021年第6期32卷 1563-1574页

作者： Pratima Pandey Sheikh nawaz Ali Prashant Kumar Champati Ray Indian Institute of Remote Sensing DehradunIndia Birbal Sahni Institute of Palaeosciences LucknowIndia

Despite several regional glacier and glacier lake inventories, the relationship between receding glacier, glacial lake evolution(glacial-lake interactions) and their sensitivity to different forcing factors have not been properly understood yet. To better understand these processes, we used satellite images collected in 1994, 2015 and 2017 to monitor the spatially-explicit evolution of glacial lakes and glacier changes. The results show a total of 1 353 glacial lakes covering an area of 7.96 km;in the year 2015. Out of these, a total of 137 glacial lakes having an area of >0.01 km;and located within 2 km periphery of mother glacier have been selected for the monitoring of spatial development between 1994 and 2017. We found an increase in the total lake area from ~4.9 to ~7.73 km;between 1994 and 2017,corresponding to an overall expansion of ~57%. The total area covered by the glaciers associated with these lakes reduced from ~365 km;in 1994 to ~358 km^(2) in 2017, accounting for a glacier loss of ~7 km^(2) and corresponding to ~1.92% reduction. Our study results are in agreement with global glacier behavior, revealing a rapid glacier recession and accelerated glacial lake expansion under an unprecedented climate change scenario. In addition, the results suggest a significant reduction in the glacier area and a close relationship between the glacier melting and lake changes.

关键词： glacial lake expansion glacier change glacier-lake interaction Central Himalaya climate

Dual-band independent phase control based on high efficiency metasurface[Invited]

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Chinese Optics Letters 2021年第10期19卷 7-14页

作者：李金星袁乐眙吴群 Shah nawaz Burokur 张狂 Department of Microwave Engineering Harbin Institute of TechnologyHarbin 150001China LEME UPLUniversite Paris NanterreF92410 Ville d'AvrayFrance

A general method to realize arbitrary dual-band independent phase control is proposed and demonstrated in this paper.A double-layered C-shape reflective meta-atom is designed to realize independent phase control with high *** a proof of concept,we propose two functional metasurfaces in the microwave region;the first metasurface performs beam steering in different directions,and the second metasurface generates achromatic beam steering at two distinct *** simulation and measurement results agree well with the theoretical *** maximum measured efficiency is 88.7%and 92.3%at 6.8 GHz and 8.0 GHz,respectively,for one metasurface,and 91.0%and 89.8%at 6.9 GHz and8.6 GHz,respectively,for the other.

关键词： dual-band independent phase control microwave metasurface high efficiency reflection geometric phase

Axisymmetric Stagnation-Point Flow of Nanofluid Over a Stretching Surface

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Advances in Applied Mathematics and Mechanics 2014年第2期6卷 220-232页

作者： M.nawaz T.Hayat Department of Humanities and Sciences Institute of Space Technology P.O.Box 2750Islamabad 44000Pakistan Department of Mathematics Quaid-i-Azam University 45320 Islamabad 44000Pakistan Department of Mathematics Faculty of SciencesKing Abdulaziz UniversityJeddah 80253Saudi Arabia

This paper investigates the laminar boundary layer flow of nanofluid induced by a radially stretching *** model exhibiting Brownian motion and thermophoresis is *** solutions for a reduced system of nonlinear ordinary differential equations are obtained by homotopy analysis method(HAM).Comparative study between the HAM solutions and previously published numerical results shows an excellent ***,temperature and mass fraction are displayed for various values of *** local skin friction coefficient,the local Nusselt number and the local Sherwood number are *** is observed that the presence of nanoparticles enhances the thermal conductivity of base *** is found that the convective heat transfer coefficient(Nusselt number)is decreased with an increase in concentration of nanoparticles whereas Sherwood number increases when concentration of nanoparticles in the base fluid is increased.

关键词： Nanofluid axisymmetric flow stagnation point Nusselt number Sherwood number

E7经济体普惠金融与经济增长关系的初步研究

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E7经济体普惠金融与经济增长关系的初步研究

作者： nawaz Ali Shah 青岛大学

学位级别：硕士

本研究旨在研究2004-2019年间普惠金融对七大新兴(E7)经济体经济增长的影响,同时以综合风险指数、政府财政开支、贸易开放度作为控制变量。普惠金融可被定义为获得合适的金融服务(如保险、信贷和存款等)的途径,这些途径被认定为是经济... 详细信息

本研究旨在研究2004-2019年间普惠金融对七大新兴(E7)经济体经济增长的影响,同时以综合风险指数、政府财政开支、贸易开放度作为控制变量。普惠金融可被定义为获得合适的金融服务(如保险、信贷和存款等)的途径,这些途径被认定为是经济增长的重要驱动因素。理论上,普惠金融可以从几个方面主要方面促进经济增长:首先,低廉而合理的信贷获得成本能够提高贫困群体的生活水平。原因如下:首先,低廉的信贷成本对低收入和弱势群体有利。在能够获得成本低廉的信贷的前提下,这些群体开始规划他们各自的生产经营活动,从而引起服务和生产产出的增加。这些弱势群体的生产和服务活动增加了国民收入,从而为宏观经济增长做出贡献。从另一方面讲,这也会提高弱势群体的收入水平,并进而提高他们生活水平。换言之,普惠金融能够降低贫困水平,从而促进经济增长。其次,普惠金融提升了保险产品和银行存款在全球范围内的可得性,进而使得个人和公司可以比较容易地在金融市场上筹集资金;而这反过来又会促使人们把他们手中的资金投资到金融系统中去。金融市场能够很好地将这些资金分配到经济体系中实体投资的长期计划中。因此,金融市场能够通过外部融资的便利化来缓解企业的资金短缺困境,进而降低了企业可能会面临的流动性风险,而这反过来又会促进企业进一步扩大它们的投资。此外,这一过程还会产生更多的产出和就业,进而提高了贫困阶层的收入。再次,普惠金融与经济增长之间的关系还可以从金融中介的视角加以理解。金融中介能够降低信息不对称所带来的负面影响,从而使得金融交易便利化,进而促进经济增长。需要指出的是,由于普惠金融与经济增长之间可能存在着相互影响的关系,因而我们很难确定它们之间因果关系的方向。一方面,普惠金融可能对经济增长产生积极影响,因为它使企业能够更容易地获得金融服务,而这在普惠程度低下的金融体系中是无法实现的。其结果就是公司的融资需求得到改善,进而促进经济增长。普惠金融有利于促进依赖外部融资的经济部门的增长。因此,高增长经济体比低增长经济体具有更高的金融普惠程度。这意味着,普惠金融能够减轻企业的融资困难,进而对经济增长产生积极的影响。在良好的金融服务体系中,贫困人口或资金短缺的群体同样有机会投资于有形资产或他们自身的教育,进而降低收入差距并促进经济增长。同样地,家庭和公司更容易获得银行服务,以及使用这些服务的女性用户的增加,对经济增长产生了强烈的积极影响。此外,普惠金融通过促进小企业的价值形成而影响经济增长,并对减贫、教育、卫生和不平等人类发展指标产生持续的溢出效应。另一方面,普惠金融也会受到经济增长的影响,高经济增长往往会提高金融的普惠程度。已有的研究结果表明,普惠金融水平与城市化、收入、不平等、有形基础设施和受教育程度等社会经济和发展指标显著相关,而这些指标显然都受到经济增长的影响。本研究具有一定的理论与实践意义,这是因为它的研究结果对许多利益攸关方而言都有用。第一,研究普惠金融与经济增长之间的关联对于E7经济体中的研究人员、学者、政策制定者、政府监管人员具有重要的理论与实践意义。第二,本研究也能对金融机构带来好处,因为它能指出影响它们市场份额和金融效率的因素是什么。在E7经济体,对于普惠金融有较好理解并加以重视的管理人员可以更好地制定政策以提升金融机构金融服务的普惠程度,进而提升它们的市场份额。第三,提升金融的普惠水平能够更好地将流入国内的国际汇兑引导至合适的投资项目中去,进而帮助各经济体克服金融风险,促进经济增长。最后且同样重要的是,普惠金融对于减少贫困非常重要。普惠金融可以提升金融服务对贫困家庭和小微企业的可得性,进而可以使大众获得更多的提升收入的机会,并提高他们自主发展的能力;而这又会对一个国家的经济增长起到积极的推动作用。选择E7经济体作为研究对象的理由如下:第一,近些年来,E7经济体取得了显著的经济增长,事实上它们的经济增长表现超过了多数其他国家。第二,这七个经济体各自的GDP总量均位居世界前20名,并在全球发展中经济体中占据主导地位。E7经济体在国际资金汇入方面也位居世界前列,特别是印度(786亿美元)、中国(674亿美元)、墨西哥(357亿美元),三个E7国家占居了全球2018年汇入接受国的前三位。一个发达的金融体系是引导这些汇款进入经济发展的先决条件,很明显,E7国家高速增长的经济表现表明它们的金融体系(包括普惠金融在内)应该比较完善。因此,以E7经济体作为研究对象,探究普惠金融与GDP增长之间的关系是很有必要的。第三,这些经济体通过全球化——尤其是通过它们之间的国际贸易以及FDI流动——紧密地联系在一起。因此可以预见,某一特定的宏观经济冲击将以类似的方式影响每个E7经济体。当然,在E7经济体之间也存在着足够的差异,进而使得对它们经济数据的统计分析成为可能。本研究的实证部分如下。本研究使用了20

关键词：普惠金融经济增长 E-7 ECM 边界检验(F Stat) CS-ARDL

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