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Chinese Chemical Letters 2010年第6期21卷 720-724页

作者： Ishaat M.Khan ahmad naeem Afaq ahmad Department of Chemistry Faculty of Science Aligarh Muslim UniversityAligarh 202002UPIndia Department of chemistry Shibli National CollegeAzamgarh 276002UPIndia

The interactions of p-dimethylaminobenzaldehyde(p-DAB) and potassium hydrogen sulphate(PHS) in equimolar ratio with various concentration of diphenylamine(solid test material) have been investigated by capillary spot-tests technique in order to investigate the effect of temperature and volume of material in *** formation of the colored boundary in the capillary is taken for the detection of organic compounds by spot-tests at different temperature and volume of solid test material.

关键词： p-DAB Capillary spot-tests Solid material Potassium hydrogen sulphate

V-Shaped Monopole Antenna with Chichena Itzia Inspired Defected Ground Structure for UWB Applications

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Computers, Materials & Continua 2020年第10期65卷 19-32页

作者： naeem ahmad Jan Saad Hassan Kiani Fazal Muhammad Daniyal Ali Sehrai Amjad Iqbal Muhammad Tufail Sunghwan Kim Department of Electrical Engineering Iqra National UniversityPeshawar25000Pakistan Department of Electrical Engineering City University of Science and Information TechnologyPeshawar25000Pakistan Department of Electrical Engineering Multimedia UniversityCyberjaya63100Malaysia Department of Mechatronics Engineering University of Engineering and TechnologyPeshawar25000Pakistan Department of Electrical Engineering University of UlsanUlsan44610Korea

Due to rapid growth in wireless communication technology,higher bandwidth requirement for advance telecommunication systems,capable of operating on two or higher bands with higher channel capacities and minimum distortion losses is *** this paper,a compact Ultra-Wideband(UWB)V-shaped monopole antenna is *** response is achieved by modifying the ground plane with Chichen Itzia inspired rectangular staircase *** proposed V-shaped is designed by incorporating a rectangle,and an inverted isosceles triangle using FR4 *** size of the antenna is 25 mm×26 mm×1.6 *** proposed V-shaped monopole antenna produces bandwidth response of 3 GHz Industrial,Scientific,and Medical(ISM),Worldwide Interoperability for Microwave Access(WiMAX),(IEEE 802.11/HIPERLAN band,5G sub 6 GHz)which with an additional square cut amplified the bandwidth response up to 8 GHz ranging from 3.1 GHz to 10.6 GHz attaining UWB defined by Federal Communications Commission(FCC)with a maximum gain of 3.83 *** antenna is designed in Ansys *** for key performance parameters of the antenna are *** measured results are in good agreement with the simulated *** to flat gain,uniform group delay,omni directional radiation pattern characteristics and well-matched impedance,the proposed antenna is suitable for WiMAX,ISM and heterogeneous wireless systems.

关键词： V-shape monopole gain staircase ultra-wideband omni-directional defected ground structure

Design of a Compact Monopole Antenna for UWB Applications

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Computers, Materials & Continua 2021年第1期66卷 35-44页

作者： naeem ahmad Jan Saad Hassan Kiani Daniyal Ali Sehrai Muhammad Rizwan Anjum Amjad Iqbal Mujeeb Abdullah Sunghwan Kim Department of Electrical Engineering Iqra National UniversityPeshawar25000Pakistan Department of Electrical Engineering City University of Science and Information TechnologyPeshawar25000Pakistan Department of Electronic Engineering The Islamia University of BahawalpurBahawalpur63100Pakistan Department of Electrical Engineering Multimedia UniversityCyberjaya63100Malaysia Department of Computer Science Bacha Khan UniversityCharsadda24420Pakistan School of Electrical Engineering University of UlsanUlsan44610Korea

In this paper,a low cost,highly efficient and low profile monopole antenna for ultra-wideband(UWB)applications is presented.A new inverted triangular-shape structure possessing meander lines is designed to achieve a wideband response and high *** design the proposed structure,three steps are utilized to achieve an UWB *** bandwidth of the proposed antenna is improved with changing meander lines parameters,miniaturization of the ground width and optimization of the feeding *** measured and simulated frequency band ranges from 3.2 to 12 GHz,while the radiation patterns are measured at 4,5.3,6 and 8 GHz frequency *** overall volume of the proposed antenna is 26×25×1.6 mm^(3);whereas the FR4 material is used as a substrate with a relative permittivity and loss tangent of 4.3 and 0.025,*** peak gain of 4 dB is achieved with a radiation efficiency of 80 to 98%for the entire *** modelling of proposed antenna is performed in ANSYS HFSS 13 software.A decent consistency between the simulated and measured results is accomplished which shows that the proposed antenna is a potential candidate for the UWB applications.

关键词： Ultra-wideband(UWB) meander lines monopole antenna high efficiency high gain ANSYS HFSS

Influence of P-enriched compost application on economics and P use efficiency of a maize–wheat rotation system

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The Crop Journal 2018年第6期6卷 651-658页

作者： Abdul Majeed Shahzada Munawar Mehdi Abid Niaz Abid Mahmood Ehsan-Ul-Haq naeem ahmad Shahid Javid Atif Mehmood Sugarcane Research Institute Faisalabad Ayub Agricultural Research InstitutePunjabPakistan Soil Fertility Research Institute LahoreAyub Agricultural Research InstitutePunjabPakistan Institute of Soil Chemistry and Environmental Sciences Ayub Agricultural Research InstitutePunjabPakistan Ayub Agricultural Research Institute PunjabPakistan Provincial Reference Fertilizer Testing Laboratory Raiwind LahorePunjabPakistan Key Laboratory of Clean Utilization Technology for Renewable Energy Ministry of AgricultureCollege of EngineeringChina Agricultural UniversityBeijing 100083China

Crop phosphorus(P) deficiency and poor utilization of added P is a major agricultural problem due to reduced solubility of soil P and rapid fixation or precipitation of applied P fertilizer in alkaline and calcareous soils. The effects of P-enriched compost and single superphosphate(SSP) fertilization on maize and wheat yields and P use efficiency in a maize–wheat rotation system were studied for three years. On a three-year average, grain yields of maize and wheat after application of P-enriched compost were increased by 18% and 24%, respectively, in comparison with sole addition of a recommended dose of SSP fertilizer. P-enriched compost addition to soil increased maize and wheat yields by 12% and 17%, respectively, compared to P fertilizer plus FYM incorporation. Soil available P concentration and P uptake were affected significantly by the addition of P-enriched compost. On average, increases in P recovery, use efficiency, and agronomic efficiency of 52%, 18%, and 43% were recorded in maize and increases of 50%, 23%, and 49% in wheat. P-enriched compost application yielded 30% and 32%higher economic returns in maize and wheat than SSP fertilization alone.

关键词： P-enriched compost Maize Wheat Farmyard manure P-uptake

Effect of different catalysts and growth temperature on the photoluminescence properties of zinc silicate nanostructures grown via vapor-liquid-solid method

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Chinese Physics B 2022年第5期31卷 657-665页

作者： Ghfoor Muhammad Imran Murtaza Rehan Abid naeem ahmad Department of Physics International Islamic UniversityIslamabad 44000Pakistan

We explore the photoluminescence properties of zinc silicate(Zn_(2)SiO_(4)) nanostructures synthesized by vapor-liquidsolid(VLS)mode of growth using three different catalysts(Sn,Ag,and Mn).Different catalysts significantly influence the growth rate which in turn has an impact on the structure and hence the photoluminescence of the prepared zinc silicate ***_(2)SiO_(4) has a wide bandgap of about 5.5 eV and in its pure form,it does not emit in visible region due to its inner shell electronic transitions between the 3 d5 energy ***,the incorporation of different catalysts(Sn,Ag and Mn)at different growth temperatures into the Zn_(2)SiO_(4) crystal growth kinetics provides wide visible spectral range of photoluminescence(PL)*** analysis shows broad multi-band spectrum in the visible region and distinct colors(red,yellow,green,blue,cyan and violet)are obtained depending on the crystalline structure of the prepared *** allowed transitions due to the effect of different catalysts on zinc silicate lattice offer a huge cross-section of absorption that generates strong *** correlation between the structural and optical properties of the synthesized nanostructures is discussed in *** synthesized photoluminescent nanostructures have potential applications in solidstate lighting and display devices.

关键词： nanostructures vapor-liquid-solid growth mode photoluminescence spectra fluorescence microscopy

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核电厂上充管热疲劳特性研究

核电厂上充管热疲劳特性研究

作者： naeem ahmad 华北电力大学(北京)

学位级别：硕士

核电厂的安全问题一直以来是困扰许多想要利用核能的消费者的主要问题。组件的疲劳失效不仅是一种重要的故障,并且对核电厂来说也是一个高危的安全隐患。核电厂的许多组件需要承受热应力,内部压力和热瞬态。这些组件一次次的承受热瞬态... 详细信息

核电厂的安全问题一直以来是困扰许多想要利用核能的消费者的主要问题。组件的疲劳失效不仅是一种重要的故障,并且对核电厂来说也是一个高危的安全隐患。核电厂的许多组件需要承受热应力,内部压力和热瞬态。这些组件一次次的承受热瞬态可能导致部件发生热疲劳现象。长期循环往复会使核电厂部件发生损坏。一些研究曾对弯管和三通管进行研究,但对化容系统中的上充管还未进行热疲劳的分析。上充管连接化容系统(RCV)和反应堆冷却剂系统(RCP)。为提高上充管的安全性,使用流固耦合(FSI)的方法对管道系统的热疲劳进行分析评估。管道的温度分布用ANSYS CFX软件计算得出。使用ANSYS瞬态结构分析,将温度分布放入管道系统的结构模型中来得出热应力。使用ANSYS利用这些应力进一步研究管道系统的疲劳特性。对CFD进行初始条件的设置;时间步长未1s,总时间为200s,取k-ω湍流模型。初步的实验结果表明热分层现象出现在上充管与RCP系统管道的连接处,因此热应力出现的位置在两管道连接处。所以使用CFD来分析较小的模型。分析确定了湍流的作用,其类似于结构的热负荷。结果显示,由于两管连接处的流体不对称,会产生绕流。使用有限元分析来映射结构中的温度变化。有限元分析表明最大热应力和最易发生热疲劳的位置在靠近主管道的环管处。发生热应力变化最大的位置在两管道连接处,靠近RCP管道出口方向的一侧管道。疲劳寿命最低处会出现在两管连接处的最大应力值处。这项研究能够快速的评估上充管的疲劳特性,为建立一种可以减小核电厂疲劳损害的方法提供有价值的信息。

关键词：流固耦合(FSI) 上充管热应力热疲劳

Expansion of human umbilical cord derived mesenchymal stem cells in regenerative medicine

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World Journal of Stem Cells 2024年第4期16卷 410-433页

作者： Shafiqa naeem Rajput Bushra Kiran naeem Anwar Ali Asmat Salim Irfan Khan Dr.Panjwani Center for Molecular Medicine and Drug Research International Center for Chemical and Biological SciencesUniversity of KarachiKarachi 75270SindhPakistan Surgical Unit 4 Dr.Ruth KM Pfau Civil HospitalKarachi 74400Pakistan Department of Physiology University of KarachiKarachi 75270Pakistan Center for Regenerative Medicine and Stem Cells Research and Department of Ophthalmology and Visual SciencesThe Aga Khan UniversityKarachi 74800SindhPakistan

BACKGROUND Stem cells are undifferentiated cells that possess the potential for self-renewal with the capacity to differentiate into multiple *** humans,their limited numbers pose a challenge in fulfilling the necessary demands for the regeneration and repair of damaged tissues or *** suggested that mesenchymal stem cells(MSCs),necessary for repair and regeneration via transplantation,require doses ranging from 10 to 400 million ***,the limited expansion of MSCs restricts their therapeutic *** To optimize a novel protocol to achieve qualitative and quantitative expansion of MSCs to reach the targeted number of cells for cellular transplantation and minimize the limitations in stem cell therapy *** Human umbilical cord(hUC)tissue derived MSCs were obtained and *** cultured cells were subjected to the following evaluation pro-cedures:Immunophenotyping,immunocytochemical staining,trilineage differentiation,population doubling time and number,gene expression markers for proliferation,cell cycle progression,senescence-associatedβ-galactosidase assay,human telomerase reverse transcriptase(hTERT)expression,mycoplasma,cytomegalovirus and endotoxin *** Analysis of pluripotent gene markers Oct4,Sox2,and Nanog in recultured hUC-MSC revealed no significant *** immunophenotypic markers CD90,CD73,CD105,CD44,vimentin,CD29,Stro-1,and Lin28 were positively expressed by these recultured expanded MSCs,and were found negative for CD34,CD11b,CD19,CD45,and *** recultured hUC-MSC population continued to expand through passage *** gene expression of Pax6,BMP2,and TGFb1 showed no significant variation between recultured hUC-MSC ***,a significant increase(P<0.001)in the mitotic phase of the cell cycle was observed in recultured *** senescence markers(hTERT expression andβ-galactosidase activity)did not show any negative effect on recultured hUC-

关键词： Human umbilical cord Mesenchymal stem cells Expansion Cell proliferation In vitro expansion Senescence

Enabling Efficient Data Transmission in Wireless Sensor Networks-Based IoT Application

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Computers, Materials & Continua 2024年第6期79卷 4197-4218页

作者： Ibraheem Al-Hejri Farag Azzedin Sultan Almuhammadi naeem Firdous Syed Information and Computer Science Department King Fahd University of Petroleum andMineralsDhahran31261Saudi Arabia Center for Cyber Resilience and Trust(CREST) Deakin UniversityGeelong3220Australia

The use of the Internet of Things(IoT)is expanding at an unprecedented scale in many critical applications due to the ability to interconnect and utilize a plethora of wide range of *** critical infrastructure domains like oil and gas supply,intelligent transportation,power grids,and autonomous agriculture,it is essential to guarantee the confidentiality,integrity,and authenticity of data collected and ***,the limited resources coupled with the heterogeneity of IoT devices make it inefficient or sometimes infeasible to achieve secure data transmission using traditional cryptographic ***,designing a lightweight secure data transmission scheme is becoming *** this article,we propose lightweight secure data transmission(LSDT)scheme for IoT *** consists of three phases and utilizes an effective combination of symmetric keys and the Elliptic Curve Menezes-Qu-Vanstone asymmetric key agreement *** design the simulation environment and experiments to evaluate the performance of the LSDT scheme in terms of communication and computation *** and performance analysis indicates that the LSDT scheme is secure,suitable for IoT applications,and performs better in comparison to other related security schemes.

关键词： IoT lightweight computation complexity communication overhead cybersecurity threats threat prevention secure data transmission Wireless Sensor Networks(WSNs) elliptic curve cryptography

The Spherical q-Linear Diophantine Fuzzy Multiple-Criteria Group Decision-Making Based on Differential Measure

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Computer Modeling in Engineering & Sciences 2024年第2期138卷 1925-1950页

作者： Huzaira Razzaque Shahzaib Ashraf Muhammad naeem Yu-Ming Chu Institute of Mathematics Khwaja Fareed University of Engineering&Information TechnologyRahim Yar Khan64200Pakistan Department of Mathematics Deanship of Applied SciencesUmm Al-Qura UniversityMeccaSaudi Arabia Department of Mathematics Huzhou UniversityHuzhou313000China

Spherical q-linearDiophantine fuzzy sets(Sq-LDFSs)provedmore effective for handling uncertainty and vagueness in multi-criteria decision-making(MADM).It does not only cover the data in two variable parameters but is also beneficial for three parametric *** Pythagorean fuzzy sets,the difference is calculated only between two parameters(membership and non-membership).According to human thoughts,fuzzy data can be found in three parameters(membership uncertainty,and non-membership).So,to make a compromise decision,comparing Sq-LDFSs is *** measures of different fuzzy sets do,however,can have several flaws that can lead to counterintuitive *** instance,they treat any increase or decrease in the membership degree as the same as the non-membership degree because the uncertainty does not change,even though each parameter has a different *** the Sq-LDFSs comparison,this research develops the differentialmeasure(DFM).Themain goal of the DFM is to cover the unfair arguments that come from treating different types of FSs opposing criteria *** to their relative positions in the attribute space and the similarity of their membership and non-membership degrees,two Sq-LDFSs formthis preference connectionwhen the uncertainty remains same in both *** to the degree of superiority or inferiority,two Sq-LDFSs are shown as identical,equivalent,superior,or inferior over one *** suggested DFM’s fundamental characteristics are *** on the newly developed DFM,a unique approach tomultiple criterion group decision-making is *** suggestedmethod verifies the novel way of calculating the expert weights for Sq-LDFSS as in *** proposed technique in three parameters is applied to evaluate solid-state drives and choose the optimum photovoltaic cell in two applications by taking uncertainty parameter *** method’s applicability and validity shown by the findings are contrasted with those obtained using various

关键词： Multi-criteria group decision-making spherical q-linear Diophantine fuzzy sets differencemeasures photovoltaic cells medical diagnosis

Variable range hopping transport and dielectric relaxation mechanism in GdCrO_(3) rare-earth orthochromite perovskite

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Journal of Rare Earths 2024年第7期42卷 1304-1316,I0004页

作者： Muhammad Javed Ayaz Arif Khan Jamal Kazmi naeem Akbar Said Nasir Khisro Amanullah Dar Aleem Dad Khan Tareen Mohd Ambri Mohamed Department of Physics The University of Azad Jammu and KashmirMuzaffarabad13100Pakistan Department of Physics University of Kotli Azad Jammu and KashmirKotli11100Pakistan Institute of Microengineering and Nanoelectronics Universiti Kebangsaan Malaysia43600BangiSelangorMalaysia Department of Mathematics University of Kotli Azad Jammu and KashmirKotli11100Pakistan

The polycrystalline GdCrO_(3)(GCO)perovskite orthochromite was synthesized by the sol-gel auto-combustion *** Rietveld refined X-ray diffraction(XRD)profile of GCO confirms that the orthorhombic phase crystallizes in perovskite crystal structure with space group *** transmission electron microscopy and selected area electron diffraction divulge the polycrystalline nature of the perovskite *** field emission scanning electron microscopy(FESEM)images reveal the microstructural polyhedral growth of grains separated by sharp grain *** chemical states of the ions present in the compound were investigated by X-ray photoelectron spectroscopy(XPS)studies,and the electrical pathways were *** impedance studies were carried out in the experimental frequency and temperature ranges of 40 Hz-4 MHz and 178-408 K,*** equivalent circuit model(RGQG)(RGBQGB)resolves the impedance response into two contributions originating from the intra-grain and inter-granular micro-constituents of the *** electrical conduction mechanism is based on the Mott variable range hopping *** complex electric modulus studies demonstrate the short-and long-range mobility of the charge carriers and rule out the presence of electrode effects on the dielectric relaxation mechanism of the *** decreasing pattern of dielectric permittivity with frequency is explained by the Maxwell-Wagner type of *** frequency dependence of the loss factor exhibits the presence of thermally activated relaxation time distribution in the material.

关键词： Auto-combustion Perovskite Electro-ceramic Dielectric Electrical transport Impedance