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Journal of Rare Earths 2019年第2期37卷 193-197页

作者： Muhammad Ayub iftikhar hussain Gul Khalid Nawaz Khurram Yaqoob Thermal Transport Laboratory School of Chemical and Materials Engineering (SCME) National University of Sciences and Technology (NUST)

In the current research work Ba_(1-x)La)xMn)yFe_(12-y)O_(19) hexa-ferrite nanoparticles of different compositions were synthesized using chemical co-precipitation technique. The structural properties were explored using X-ray diffractions(XRD), scanning electron microscopy(SEM) and Fourier transmission infrared spectroscopy(FTIR). XRD indexed pattern confirms the formation of M-type hexagonal phase. The crystallite size of synthesized samples ranges from 13 to 34 ± 2 nm. FTIR peaks observe also confirmed the presence of metaloxygen bond of the desired product. The position of peak at 467 cm^(-1) corresponds to A_2 u vibration for octahedral Fe(4+)-O and peak position E1 u corresponds to vibration of Fe(3+)O4 octahedral bonds. The band v_1 in range(677-559 cm^(-1)) and v_2 in frequency range(356-419 cm^(-1)) are associated to A and B *** properties of all compositions were measured with frequency. The dielectric constant, loss and tangent loss decrease from 26 to 9, 25 to 2 and 0.94 to 0.14, respectively with frequency. DC electrical resistivity is increased with dopant concentration increasing from 2.15 × 10~4 to 1.92 ×10~5 Ω·cm.

关键词： Co-precipitation Electrical properties Dielectric X-ray diffraction Rare earths

Enhancing Dielectric and Mechanical Behaviors of Hybrid Polymer Nanocomposites Based on Polystyrene,Polyaniline and Carbon Nanotubes Coated with Polyaniline

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Chinese Journal of Polymer Science 2016年第12期34卷 1500-1509页

作者： Tanveer ul Haq Zia Ahmad Nawaz Khan Majid hussain Ibrar Hassan iftikhar hussain Gul Department of Materials Engineering School of Chemical and Materials EngineeringNational University of Sciences and Technology

The dielectric and mechanical properties of hybrid polymer nanocomposites of polystyrene/polyaniline/carbon nanotubes coated with polyaniline （pCNTs） have been investigated using impedance analyzer and extensometer. The blends of PS/PANI formed the heterogeneous phase separated morphology in which pCNTs are dispersed uniformly. The incorporation of a small amount of pCNTs into the blend of PS/PANI has remarkably increased the dielectric properties. Similarly, the AC conductivity of PS/PANI is also increased five orders of magnitude from 1.6 × 10^-10 to 2.0×10^-5 ***-1 in the hybrid nanocomposites. Such behavior of hybrid nanocomposites is owing to the interfacial polarization occurring due to the presence of multicomponent domains with varying conductivity character of the phases from insulative PS to poor conductor PANI to highly conductive CNTs. Meanwhile, the tensile modulus and tensile strength are also enhanced significantly up to 55% and 160%, respectively, without much loss of ductility for three phase hybrid nanocomposites as compared to the neat PS. Thereby, the hybrid nanocomposites of PS/PANI/pCNTs become stiffer, stronger and tougher as compared to the neat systems.

关键词： Nanocomposites Carbon nanotubes Dielectric behavior Mechanical properties Polystyrene.

Heteroatom doping in 2D MXenes for energy storage/conversion applications

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Advanced Powder Materials

Advanced Powder Materials 2024年第6期3卷 150-177页

作者： Sumanta Sahoo Rajesh Kumar iftikhar hussain Kaili Zhang School of Chemical Engineering Yeungnam University280 Daehak-roGyeongsanGyeongbuk38541Republic of Korea Department of Mechanical Engineering Indian Institute of TechnologyKanpur208016Uttar PradeshIndia Department of Mechanical Engineering City University of Hong Kong83 Tat Chee AvenueKowloonHong KongChina

MXenes(inorganic metal carbides,nitrides,and carbonitrides)are currently the rising star of two-dimensional(2D)*** its discovery in 2011,initial research was concentrated on pristine MXenes ***,in the last few years,the MXene family has been expanded with the exploration of novel double MXenes,synthesis of non-Ti MXenes,and heteroatom doping of *** current review article delivers an exclusive overview of the current research trends on the heteroatom doping of *** recent advances in heteroatom doping of MXenes(majorly Ti-MXenes)for energy storage/conversion applications including secondary batteries(Li-ion,Li–S,Na–S,Na-ion,K-ion,Zn-ion batteries),supercapacitors,electrocatalysis,*** summarized.A brief overview of the defects as well as doping in various 2D materials is included in the *** doping strategies of MXenes are ***,the impact of artificial intelligence/machine learning on MXene research is also concisely ***,the advantages of doping on MXenes are discussed in ***,the existing challenges and future prospects of doped MXenes are *** is expected that the current review will open new prospects for the fabrication of advanced energy devices through heteroatom doping of MXenes.

关键词： MXene Doping Supercapacitor Secondary battery Electrocatalysis

Cluster Formation and Cluster Head Selection Approach for Vehicle Ad-hoc Networks Using K-Mean and Floyd-Warshall Techniques

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Cluster Formation and Cluster Head Selection Approach for Ve...

作者： iftikhar hussain 大连理工大学

学位级别：硕士

车载自组织网络(VANET)在智能交通系统(ITS)中具有重要的地位。它可以传输关于道路和交通状况的重要信息,发送安全信息并为乘客提供娱乐服务。VANET为车辆提供相互连接以实现不同类型的消息,例如,交换普通消息,路径拥塞消息,安全消息,... 详细信息

车载自组织网络(VANET)在智能交通系统(ITS)中具有重要的地位。它可以传输关于道路和交通状况的重要信息,发送安全信息并为乘客提供娱乐服务。VANET为车辆提供相互连接以实现不同类型的消息,例如,交换普通消息,路径拥塞消息,安全消息,或路径正在建设消息等。VANETs是移动自组织网络(MANET)的一种具体形式,其中使用高动态节点来执行操作。它们主要用于城市地区的安全旅行。由于VANET由大量的车流组成,所以使用聚类算法对处于网络范围内的车辆进行聚类。簇头节点通过过程指定来收集周围的所有信息。本研究通过使用K-Mean和Floyd-Warshall算法引入了一种新的簇头选择方法。所提出的技术首先将车辆组的点分开,而Floyd-Warshall算法计算所定义的集群内每辆车的所有最短距离对。选择一个簇中平均距离最小的车辆作为簇头。FloydWarshall算法选择总体上位于中心区域的车辆作为簇头,因此其稳定时间将显着提高。我们使用K-Means&Floyd-Warshall算法提出了一种用于车载Ad-hoc网络(VANET)的集群形成和簇首选择方法。所提出的算法有两个部分,即使用K-Means为车辆组提供分割部分,然后在第二部分中使用Floyd-Warshall算法计算集群内每个车辆的所有最短路径。FW算法中簇头选择的标准是,簇中节点与簇中所有其他车辆的平均距离较小。通过仿真表明,我们提出的方案在平均PSNR,传输距离,平均连通性和簇头平均持续时间方面优于现有算法。结果显示不同车辆数量具有不同的平均峰值信噪比(PSNR)。直观地说,车辆数量越多,信号质量越高。随着车辆数量的增加,信号会导致较小的路径损失。就平均PSNR而言,与VWCA和CTIG相比,我们提出的KMFW方案具有更好的性能。在每公里有一定数量的车辆后,在本例为250辆,平均PSNR将保持不变。然而,对于较少数量的车辆,拟议的KMFW表现优于VWCA和CTIG。

关键词：车载自组织网络(VANETs) 移动自组织网络(MANETs) K-Mean均值聚类簇首选择 Floyd-Warshall算法

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

Infield superconducting properties of nano-sized Ag added Cu0.5Tl0.5Ba2Ca2Cu3O10-δ

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Progress in Natural Science:Materials International 2017年第4期27卷 487-490页

作者： M.W.Rabbani Liaqat Ali M.Mumtaz iftikhar hussain Gul Materials Research Laboratory Department of Physics FBAS International Islamic University(IIU) Department of Material s Engineering(ME) Thermal Transport Laboratory(TTL)School of Chemical and Materials Engineering(SCME)National University of Science and Technology(NUST)

Infield superconducting properties of {(Ag)/CUTl-1223};(x = 0, 0.5,1.***.2.0 and 4.0 wt %) nanoparticlessuperconductor composites were investigated under different applied magnetic field up to H = 8 T. The increase in critical temperature {T(0)} and decrease in normal state resistivity(p) were observed with increasing contents of Ag nanoparticles in CuTl-1223 superconducting matrix. The value of T(K) remained almost unaffected by applying external magnetic field, but a decreasing trend in T(0) was observed by increasing the value of external applied magnetic field. The transition region below T(K) showed Arrhenius behavior due to thermally activated flow of magnetic vortices. Enhancement in flux flow activation energy(U) and suppression in transition width(ΔT) of CuTl-1223 phase with addition of Ag nanoparticles showed the improvement in flux pinning strength of superconductor.

关键词： Ag)_x/CuTl-1223 composites Activation energy Transition width Flux pinning Critical field

Field evaluation of some bait additives against Indian crested porcupine(Hystrix indica)(Rodentia:Hystricidae)

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Integrative Zoology 2013年第3期8卷 285-292页

作者： Muhammad MUSHTAQ iftikhar hussain Afsar MIAN Shahid MUNIR Irfan AHMED Abdul Aziz KHAN Department of Zoology PMAS Arid Agriculture UniversityRawalpindiPakistan Wildlife Management PMAS Arid Agriculture UniversityRawalpindiPakistan National Agricultural Research Centre IslamabadPakistan

This research study evaluated the effect of different additives on the bait consumption by Indian crested porcupine,a serious forest and agricultural pest,under field *** additives(saccharin,common salt,bone meal,fish meal,peanut butter,egg yolk,egg shell powder,yeast powder,mineral oil and coconut oil)at 2 and 5%each were tested for their relative preference,using groundnut-maize(1:1)as basic *** the additives were tested under a no-choice test *** control tests,no additive was mixed with the basic *** at 5%concentration significantly enhanced the consumption of bait over the basic bait,while 2%saccharin supplemented bait resulted in a non-significant bait *** other additives did not enhance the consumption of the bait material;rather,these worked as ***,the repellency was lowest with the common salt,followed by egg yolk,egg shell powder,bone meal,peanut butter,mineral oil,fish meal and yeast powder,while coconut remained the most repellent *** present study suggested that groundnut-maize(1:1)supplemented with 5%saccharin was the preferred bait combination,and can be used with different rodenticides for the management of Indian crested porcupine.

关键词： additives baits evaluation Hystrix indica Indian crested porcupine

A review on current conventional and biotechnical approaches to enhance biosynthesis of steviol glycosides in Stevia rebaudiana

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Chinese Journal of Chemical Engineering 2021年第2期34卷 92-104页

作者： Samra Basharat Ziyang Huang Mengyue Gong Xueqin Lv Aqsa Ahmed iftikhar hussain Jianghua Li Guocheng Du Long Liu Science Center for Future Foods Jiangnan UniversityWuxi 214122China Key Laboratory of Carbohydrate Chemistry and Biotechnology Ministry of EducationJiangnan UniversityWuxi 214122China School of Food Science and Technology Jiangnan UniversityWuxi 214122China

Stevia rebaudiana Bertoni is commonly called stevia and mostly found in the north east regions of South *** is an herbaceous and shrubby plant belonging to the Asteraceae *** is considered as a natural sweetener and a commercially important plant *** leaves of *** contain steviol glycosides(SGs)which are highly potent and non-caloric *** sweetening property of *** is contributed to the presence of these high potency,calorie free steviol *** are considerably suitable for replacing sucrose and other artificial sweetening agents which are used in different industries and *** amount in the plant mostly varies from 8%to 10%,and the enhancement of SGs is always in *** glycosides have the potential to become healthier alternatives to other table sugars for having desirable taste and zero *** are almost 300 times sweeter than *** used as alternative sugar intensifier the commercial value of this plant in biopharmaceutical,food and beverages industries and in international market is increasing day by *** have made stevia an important part of the medicinal world as well as the food and beverage industry,but the limited production of plant material is not fulfilling the higher global market ***,researchers are working worldwide to increase the production of important SGs through the intercession of different biotechnological approaches in *** review aims to describe the emerging biotechnological strategies and approaches to understand,stimulate and enhance biosynthesis of secondary metabolites in *** and biotechnological methods for the production of steviol glycosides have been briefly reviewed and discussed.

关键词： Steviol glycosides Biosynthesis Secondary metabolites Stevia rebaudiana

Aspergillus tubingensis Causes Leaf Spot of Cotton (Gossypium hirsutum L.) in Pakistan

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Phyton-International Journal of Experimental Botany 2020年第1期89卷 103-109页

作者： Maria Khizar Urooj Haroon Musrat Ali Samiah Arif iftikhar hussain Shah Hassan Javed Chaudhary Muhammad Farooq hussain Munis Department of Plant Sciences Faculty of Biological SciencesQuaid-i-Azam UniversityIslamabadPakistan Department of Plant Sciences School of Agriculture and BiologyShanghai Jiao Tong UniversityShanghaiChina

Cotton(Gossypium hirsutum L.)is a key fiber crop of great commercial *** phytopathogens decimate crop production by causing various *** July-August 2018,leaf spot symptoms were recurrently observed on cotton leaves in Rahim Yar Khan,Pakistan and adjacent *** leaf samples were collected and plated on potato dextrose agar(PDA)*** agent of cotton leaf spot was isolated,characterized and identified as Aspergillus tubingensis based on morphological and microscopic *** identification of pathogen was done on the comparative molecular analysis of CaM andβ-tubulin gene *** analysis of both sequenced genes showed 99%similarity with ***’s postulates were followed to confirm the pathogenicity of the isolated *** plants were inoculated with fungus and similar disease symptoms were *** was re-isolated and identified to be identical to the inoculated *** our knowledge,this is the first report describing the involvement of *** in causing leaf spot disease of cotton in Pakistan and around the world.

关键词： Aspergillus tubingensis CaM gene Koch’s postulates cotton

Abundance and Breeding of the Common Skittering Frog(Euphlyctis cyanophlyctis)and Bull Frog(Hoplobatrachus tigerinus)at Rawal Lake,Islamabad,Pakistan

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Asian Herpetological Research 2011年第4期2卷 245-250页

作者： Fozia TABASSUM Muhammad RAIS Maqsood ANWAR Tariq MEHMOOD iftikhar hussain Shahid ALI KHAN Department of Wildlife Management Pir Mehr Ali Shah Arid Agriculture University

The population density and breeding of two frog species, i. e., the Skittering Frog （Euphlyctis eyanophlyctis） and the Bull Frog （Hoplobatrachus tigerinus） were studied at Rawal Lake, Islamabad, Pakistan, by using visual encounter method from September 2009 to August 2010. Mean population density for the two frogs was 1.55 ± 0.44 frogs per ha, with that for the Skittering Frog being 1.09 ± 0.33 frogs/ha and that of the Bull Frog 0.46 ± 0.11 frog/ha, respectively. It is concluded that both frog species are explosive breeders, i. e., their breeding activities were confined to the first showers of the monsoon season. The mean spawn weight of the Skittering Frog was 1.5 g with more than 1000 eggs in each spawn, while that of the Bull Frog was 0.26 g with less than 1000 eggs in a spawn. The spawning sites of the two species were investigated in detail. Generally, no threat to their populations was observed. However, the opening of the spillway of Rawal Dam following the torrential rain destroyed the breeding sites of the frogs. It is maintained that the event did not produce any significant impact on their populations and breeding as the two species were quite common.

关键词： Ranidae population status breeding habitat destruction