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Dramatic changes in anatomical traits of a C4 grass Chrysopogon serrulatus Trin.(Poaceae)over a 1000 m elevational gradient

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Journal of Mountain Science 2023年第5期20卷 1316-1335页

作者： FATIMA Sana HAMEED Mansoor AHMAD farooq AHMAD Muhammad Sajid Aqeel ANWAR Majid MUNIR Mahwish ASHRAF Muhammad SHAH Syed Mohsan Raza BASHARAT Sana AHMAD Iftikhar KHALIL Sangam Department of Botany Government Sadiq College Women UniversityBahawalpur 53100Pakistan Department of Botany University of Agriculture FaisalabadFaisalabad 38040Pakistan Department of Pharmacy Riphah International University Lahore 53770Pakistan Institute of Molecular Biology and Genetic Engineering The University of LahoreLahore 53770Pakistan Department of Botany Division of Science and TechnologyUniversity of EducationLahore 53770Pakistan Department of Forestry Range&Wildlife ManagementThe Islamia University of BahawalpurBahawalpur 53100Pakistan

Chrysopogon serrulatus(false beard-grass)is a dominant component of vegetation in the foothills of the *** study whole plant morphology,individuals of *** were collected from three plots at each of six locations spanning from 400 to 1,400 *** population colonizing the highest elevation modifications in different plant *** showed increased metaxylem number and *** the stem,especially outside of the vascular tissue,there was intensive sclerification indicative of increased xeromorphy as a survival *** the highest elevation,leaves were wider;aerenchyma formation and increased sclerification were noted in the leaf sheath;and a greater proportion of storage parenchyma was observed in the leaf blade,all indicators of *** contrast,leaves at lower elevations had xeric morphological features such as increased epidermal thickness,sclerification and more developed metaxylem *** conclusion,shifting of morphological features in below-and above-ground plant parts of *** were linked to shifts in environmental factors along this elevation gradient,thus enabling the successful distribution of this species along this elevation gradient.

关键词： Adaptive component Storage parenchyma Sclerification Metaxylem Aerenchyma

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考虑故障电流限制器与柔性交流输电系统的分布式电源低电压穿越效率提升方法研究

考虑故障电流限制器与柔性交流输电系统的分布式电源低电压穿越效...

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作者： farooq Muhammad 华北电力大学(北京)

学位级别：硕士

风力发电(WPG)是能够产生电力以满足能源需求的最先进技术之一。随着机械设备的发展,基于双馈感应发电机(DFIG)的风力涡轮机得到了很大的改进。使用基于双馈感应发电机的风力涡轮机的主要优点是它们使电力系统的运行更加可靠,另外使用... 详细信息

风力发电(WPG)是能够产生电力以满足能源需求的最先进技术之一。随着机械设备的发展,基于双馈感应发电机(DFIG)的风力涡轮机得到了很大的改进。使用基于双馈感应发电机的风力涡轮机的主要优点是它们使电力系统的运行更加可靠,另外使用双馈感应发电机可在较宽范围内的转子速度下运行,并且可以减少变流器承载的功率量,从而显着降低变流器成本。目前,电力系统中有许多设备作用于提高系统稳定性并降低预期的高故障电流,包括断路器、熔断器、串联电抗器和高阻抗变压器,然而,这些传统设备在反应速度、功率损耗和系统稳定性反面存在难题。本节介绍了一些用于提高电力系统可靠性的新器件,例如超导故障电流限制器(SFCL)、FACTS器件和电力系统稳定器(PSS)。本文讨论了使用基于双馈感应发电机的风力涡轮机并网时面临的稳定性问题以及使用上述系统的分布式发电的稳定性损失问题。研究的主要目的是使用超导故障电流限制器(SFCL)和柔性交流输电系统(FACTS)设备解决低电压穿越(LVRT)和其他稳定性问题。根据实验结果表明超导故障电流限制器不仅提高了双馈感应发电机的解决低电压穿越能力,而且还改善了双馈感应发电机在电网故障情况下的动态行为。报告数据有助于将电网的柔性交流输电系统商业化,还可以观察到不同类型的PSS对并网风能系统稳定性的影。最后的结果验证了所提方法的有效性。为了观察FACTS器件对LVRT能力的影响,引入了与故障阻抗串联的远程故障,它在PCC处产生32%的电压骤降,即0.68pu。使用STATCOM电压提高到0.76pu,而使用SVC电压提高到 0.74pu。

关键词：低电压穿越能力 WECS-SFCL 带有FACTS设备的WECS 分布式发电(DG) 多机系统稳定性的PSS

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Small RNA deep sequencing reveals the presence of multiple viral infections in cucurbit crops in Guangdong,China

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Journal of Integrative Agriculture 2022年第5期21卷 1389-1400页

作者： LI Zheng-gang NONG Yuan Tahir farooq TANG Ya-fei SHE Xiao-man YU Lin LAN Guo-bing ZHOU Xue-ping HE Zi-fu Guangdong Provincial Key Laboratory of High Technology for Plant Protection Plant Protection Research InstituteGuangdong Academy of Agricultural SciencesGuangzhou 510640P.R.China State Key Laboratory for Biology of Plant Diseases and Insect Pests Institute of Plant ProtectionChinese Academy of Agricultural SciencesBeijing 100193P.R.China State Key Laboratory of Rice Biology Institute of BiotechnologyZhejiang UniversityHangzhou 310058P.R.China

Viral diseases are among the most critical damaging factors that impose a global threat to the cucurbit *** is the world’s leading country for the production and consumption of ***,a province in southern China dominated by the tropical and subtropical climate,favors the survival of different plant viruses and their *** main cucurbit crops showing various disease symptoms were surveyed and collected to identify viruses infecting cucurbits in Guangdong during 2018–*** the field,the incidence ranged from 5-30%,or even 60-100% in the case of severely infected cucurbits.A total of 357 symptomatic samples were collected and subsequently screened for cucurbit viruses by small RNA deep sequencing and assembly(sRSA).Seventeen virus species belonging to 10 genera were identified in the five main cucurbit *** most common viruses were papaya ringspot virus(PRSV;Potyvirus),zucchini tigre mosaic virus(ZTMV;Potyvirus),zucchini yellow mosaic virus(ZYMV;Potyvirus),and watermelon silver mottle virus(WSMoV;Orthotospovirus),with infection rates of 24.4,19.0,17.1,and 14.3%,***,the most prevalent viruses were melon yellow spot orthotospovirus(MYSV)in cucumber,PRSV in squash,cucumber green mottle mosaic virus(CGMMV;Tobamovirus)in bottle gourd,WSMoV in white gourd,and ZYMV in *** infections were prevalent,and the types of mixed infections varied substantially in different cucurbit ***,the full-length nucleotide sequences of watermelon green mottle mosaic virus(WGMMV),CGMMV,and watermelon virus A(WVA;Wamavirus)identified in bottle gourd were cloned and *** study is the first reporting WGMMV infecting bottle gourd in China *** summary,the results demonstrate that in Guangdong,the most prevalent viruses belong to potyviruses,orthotospoviruses,and tobamoviruses *** findings will facilitate agricultural researchers and farmers to plan and implement effective disease control strategies aimi

关键词： cucurbit viruses small RNA deep sequencing phylogenic analyses potyviruses orthotospoviruses tobamoviruses

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Catalytic performance of Cu-and Zr-modified beta zeolite catalysts in the methylation of 2-methylnaphthalene

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Petroleum Science 2019年第1期16卷 161-172页

作者： Fatih Gülec farooq Sher Ali Karaduman Department of Chemical and Environmental Engineering University of NottinghamUniversity Park Department of Chemical Engineering Faculty of EngineeringAnkara University

2,6-Dimethylnaphthalene(2,6-DMN) is a commercially important chemical for the production of polyethylenenaphthalate and polybutylene naphthalate. However, its complex synthesis procedure and high production cost significantly reduce the use of 2,6-DMN. In this study, the synthesis of 2,6-DMN was investigated with methylation of 2-methylnaphthalene(2-MN) over metal-loaded beta zeolite catalysts including beta zeolite, Cu-impregnated beta zeolite and Zr-impregnated beta zeolite. The experiments were performed in a fixed-bed reactor at atmospheric pressure under a nitrogen atmosphere. The reactor was operated at a temperature range of 400–500 °C and varying weight hourly space velocity between 1 and 3 h^(-1).The results demonstrated that 2,6-DMN can be synthesized by methylation of 2-MN over beta type zeolite *** 2,6-DMN, the product stream also contained other DMN isomers such as 2,7-DMN, 1,3-DMN, 1,2-DMN and 2,3-DMN. The activity and selectivity of beta zeolite catalyst were remarkably enhanced by Zr impregnation, whereas Cu modification of beta zeolite catalyst had an insignificant effect on its selectivity. The highest conversion of 2-MN reached81%, the highest ratio of 2,6-DMN/2,7-DMN reached 2.6 and the highest selectivity of 2,6-DMN was found to be 20% by using Zr-modified beta zeolite catalyst.

关键词： Methylation Naphthalene derivatives Polyethylenenaphthalate 2,6-Dimethylnaphthalene and beta zeolite catalyst

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外交智库在巴基斯坦外交政策制定中的作用

外交智库在巴基斯坦外交政策制定中的作用

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作者： Qaisar farooq 吉林大学

学位级别：硕士

本文旨在探讨智库在巴基斯坦外交政策制定中的作用和职能。智库是关切社会、政治、外交和战略、经济、技术、文化等诸多事务的研究机构。它们为决策者提供系统性、组织性的分析,以便于决策者就国家、区域和全球事务做出充分的知情和高... 详细信息

本文旨在探讨智库在巴基斯坦外交政策制定中的作用和职能。智库是关切社会、政治、外交和战略、经济、技术、文化等诸多事务的研究机构。它们为决策者提供系统性、组织性的分析,以便于决策者就国家、区域和全球事务做出充分的知情和高质量决策。多数智库都是非政府组织、非营利性组织和非党派组织,部分是政府内部的半自治机构。某些智库还与特定的政党、商业团体或军队之间存在着联系。与议会、大学和国家官僚机构相比,智库可谓是政策领域中一个新事物。在讨论和形成全面公共政策方面,智库发展迅速并已成为软实力的重要工具之一,它为国家加强其在国内、区域和国际层面的领导能力提供了一种路径。智库最重要的职责之一是应对国家在未来可能面临的新的、关键和复杂的挑战,并培养出能意识到这些问题的决策者。无论是发达国家还是新兴国家,智库的数量和重要性都在急剧增加。近几十年,巴基斯坦的外交智库以更快的速度出现和扩张,它们通过及时的分析,对政策议题特别是外交政策塑造产生了重大影响。本文目的在于考察巴基斯坦外交智库的历史发展和成长,侧重分析巴基斯坦不同外交智库的特点、机制以及它们是如何运作的。巴基斯坦智库最突出的特点是它具有直接或者间接影响官方政策的能力。本文的研究方法包括案例研究、比较研究以及对文献研究方法。本文使用精英主义、中央集权主义、多元主义和制度主义的方法分析巴基斯坦的智库。为了分析智库的影响以及它们如何影响政策,本文研究智库在不同阶段影响决策者的路径。本文讨论巴基斯坦外交智库在背景和组织方面遇到的障碍和限制。本文详细解释了巴基斯坦外交智库的功能是如何被侵蚀的。派别之争经常被用来解释研究结果和建议,智库与官僚机构和捐助者（包括国内和国际）的互动,往往会影响外交智库影响政策的能力。总地来说,本研究分为五章:第一章是开篇部分,对本文研究问题、意义和目标进行了定义和考察。本文的基本问题是外交智库在巴基斯坦外交政策制定中角色。本文提出,智库在巴基斯坦的外交政策制定中发挥了重要且有影响力的作用和贡献。在巴基斯坦这样的发展中国家,关于外交政策智库真正的学术研究以及学术著作严重不足。本文旨在探讨外交政策研究中一个相对未开发的课题。希望本文能激发人们对这些问题的兴趣,以及未来更多对巴基斯坦外交智库的研究。导论部分还解释了研究方法,其中包括文献整理、观察、案例研究和比较研究。该部分还对一些相关的文献和阅读材料进行了讨论。第二章详细分析了巴基斯坦外交智库的起源和类型,并讨论了各种外交智库的运作机制和特点。智库正在逐渐成为现代国家政府中越来越重要的角色。巴基斯坦的智库被分为:政府附属型、自治型和大学附属型。这些智库已经具备吸引决策者的注意以及直接或间接影响决策者的能力,以便他们能够随时寻求智库的意见和建议。学者和研究人员认为,由于这一独特的特性,巴基斯坦的智库对形成和制定外交政策具有最显著的影响。它们日益成为国家软实力的重要载体,在国际关系中发挥着不可或缺的作用,并且成为国际竞争中的关键因素之一。第三章探讨影响外交政策制定中智库的变量因素。要量化或分析智库的影响以及它们如何实现政策影响,首先要了解智库在影响决策过程的不同阶段采用的各种策略。智库为重要的辩论和讨论提供了一个开放的平台,并对公民进行有关国际事务的教育。智库作为一种软实力工具,可以帮助一个国家提高其在国家和国际层面的领导地位。虽然智库的相关性及其对巴基斯坦内部和外交政策的贡献已经得到承认,但还需要进一步评估其贡献的范围和精确性。本文阐述了背景环境和组织缺陷如何对外交智库的效力产生不利影响。第四章集中于案例研究。案例研究是在现实世界中对特定案例进行深入和详细的考察。本文详细分析了巴基斯坦三大主要外交智库的作用和活动及其对外交决策的影响。这三个机构是伊斯兰堡战略研究所（ISSI）、巴基斯坦-中国研究所（PCI）和穆斯林研究所（MI）。巴基斯坦-中国研究所是一个非政府、非政治的智库。它倾向于是一个改善两国在所有领域之间的人与人之间关系的非政府场所,特别是在国防和外交、教育和能源、经济和环境方面,尤其关注青年和妇女。1973年伊斯兰堡战略研究所成立,它是一个独立的非营利性研究和分析小组,其目的是为对全球和平与安全产生影响的国内和国际战略问题提供有深度的信息和公正的研究。穆斯林研究所是一个非营利性的智库,其使命是促进穆斯林世界的和平、稳定、繁荣和领导地位,这是一个不隶属于任何政党的非营利性组织。第五章,最后一部分讨论了政府官员为改进和扩大外交智库在国际决策中的作用所应考虑和关注的意见和建议。本研究中提出的建议也可能成为研究人员和分析人员关于未来如何进一步提高外交智库效率的主要原则。

关键词：智库外交政策经济巴基斯坦

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Weighted ebyev-Ostrowski type inequalities

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Applied Mathematics and Mechanics(English Edition) 2007年第7期28卷 901-906页

作者： Arif Rafiq Nazir Ahmad Mir farooq Ahmad Mathematics Department COMSATS Institute of Information TechnologyIslamabad 44000Pakistan Centre for Advanced Studies in Pure and Applied Mathematics Bahanddin Zakariya UniversityMultan 60800Pakistan

In account of the famous Cebysev inequality, a rich theory has appeared in the literature. We establish some new weighted Cebysev type integral inequalities. Our proofs are of independent interest and provide new esti... 详细信息

关键词： Cebysev type inequalities L∞ (a b) spaces absolutely continuous functions weight functions

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Remediation of sulfidic wastewater by catalytic oxidation with hydrogen peroxide

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Journal of Environmental Sciences 2009年第12期21卷 1735-1740页

作者： Naveed Ahmad Saikat Maitra Binay Kanti Dutta farooq Ahmad Department of Chemical Engineering Universiti Teknologi PETRONAS Department of Chemical Engineering The Petroleum Institute

Oxidation of sulfide in aqueous solution by hydrogen peroxide was investigated in the presence of hydrated ferric oxide catalyst. The ferric oxide catalyst was synthesized by sol gel technique from ferric chloride and ammonia. The synthesized catalyst was characterized by Fourier transform infrared spectroscopy, X-Ray diffraction analysis, scanning electrom microscope and energy dispersive X-ray analysis. The catalyst was quite effective in oxidizing the sulfide by hydrogen peroxide. The effects of sulfide concentration, catalyst loading, H2O2 dosing and temperature on the kinetics of sulfide oxidation were investigated. Kinetic equations and activation energies for the catalytic oxidation reaction were calculated based on the experimental results.

关键词： catalytic oxidation wastewater kinetic equation hydrogen peroxide sodium sulfide remediation

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Degradation of polyacrylamide (PAM) and methane production by mesophilic and thermophilic anaerobic digestion: Effect of temperature and concentration

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Frontiers of Environmental Science & Engineering 2020年第6期14卷 75-85页

作者： Mona Akbar Muhammad farooq Saleem Khan Ling Qian Hui Wang State Key Joint Laboratory of Environment Simulation and Pollution Control School of EnvironmentTsinghua UniversityBeijing 100084China Sino-Japan Friendship Center for Environmental Protection Beijing 100029China

Polyacrylamide(PAM)is generally employed in wastewater treatment processes such as sludge dewatering and therefore exists in the ***,it degrades slowly and can deteriorate methane yield during anaerobic digestion(AD).The impact or fate of PAM in AD under thermophilic conditions is still *** study mainly focuses on PAM degradation and enhanced methane production from PAM-added sludge during 15 days of thermophilic(55°C)AD compared to mesophilic(35°C)*** and PAM dose from 10 to 50 g/kg TSS were *** results showed that PAM degraded by 76%to 78%with acrylamide(AM)content of 0.2 to 3.3 mg/L in thermophilic ***,it degraded only 21%to 30%with AM content of 0.5 to 7.2 mg/L in mesophilic *** methane yield was almost 230 to 238.4 mL/g VSS on the 8th day in thermophilic AD but was 115.2 to 128.6 mL/g VSS in mesophilic *** investigation revealed that thermophilic AD with continuous stirring not only enhanced PAM degradation but also boosted the organics release from the sludge with added PAM and gave higher methane yield than mesophilic AD.

关键词： Polyacrylamide(PAM)degradation Acrylamide(AM) Mesophilic anaerobic digestion Thermophilic anaerobic digestion Methane production

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Comparison of Energy Harvesting Systems for Wireless Sensor Networks

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International Journal of Automation and computing 2008年第4期5卷 334-347页

作者： James M.Gilbert farooq Balouchi Department of Engineering University of Hull

Wireless sensor networks (WSNs) offer an attractive solution to many environmental,security,and process monitoring ***,one barrier to their fuller adoption is the need to supply electrical power over extended periods of time without the need for dedicated *** harvesting provides a potential solution to this problem in many *** paper reviews the characteristics and energy requirements of typical sensor network nodes,assesses a range of potential ambient energy sources,and outlines the characteristics of a wide range of energy conversion *** then proposes a method to compare these diverse sources and conversion mechanisms in terms of their normalised power density.

关键词： Energy harvesting energy scavenging wireless sensor networks (WSNs) energy management

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Non-Associative Algebra Redesigning Block Cipher with Color Image Encryption

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Computers, Materials & Continua 2021年第4期67卷 1-21页

作者： Nazli Sanam Asif Ali Tariq Shah Ghazanfar farooq Department of Mathematics Quaid-i-Azam UniversityIslamabad44000Pakistan Department of Computer Science Quaid-i-Azam UniversityIslamabad44000Pakistan

The substitution box(S-box)is a fundamentally important component of symmetric key *** S-box is a primary source of non-linearity in modern block ciphers,and it resists the linear *** approaches have been adopted to construct S-boxes.S-boxes are commonly constructed over commutative and associative algebraic structures including Galois fields,unitary commutative rings and cyclic and non-cyclic finite *** this paper,first a non-associative ring of order 512 is obtained by using computational techniques,and then by this ring a triplet of 8×8 S-boxes is *** motivation behind the designing of these S-boxes is to upsurge the robustness and broaden the key space due to non-associative and noncommutative behavior of the algebraic structure under consideration.A novel color image encryption application is anticipated in which initially these 3 S-boxes are being used to produce confusion in three layers of a standard RGB ***,for the sake of diffusion 3D Arnold chaotic map is used in the proposed encryption scheme.A comparison with some of existing chaos and S-box dependent color image encryption schemes specs the performance results of the anticipated RGB image encryption and observed as approaching the standard prime level.

关键词： Block cipher s-box nonlinearity color image encryption 3D chaotic map

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