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Journal of Thermal Science 2014年第6期23卷 523-534页

作者： Syed Noman Danish Shafiq Rehman Qureshi Abdelrahman EL-Leathy salah ud-din khan Usama Umer Ma Chaochen Sustainable Energy Technologies Center King Saud University National University of Sciences and Technology PNS JauharKarachiPakistan Mechanical Engineering Department King Saud University FARCAMT Advanced Manufacturing InstituteKing Saud University Beijing Institute of Technology

Extensive numerical investigations of the performance and flow structure in an unshrouded tandem-bladed centrifugal compressor are presented in comparison to a conventional *** characteristics are explored for various tip clearance levels,axial spacings and circumferential *** impeller was modified to tandem-bladed design with no modifications in backsweep angle,meridional gas passage and camber distributions in order to have a true comparison with conventional *** degradation is observed for both the conventional and tandem designs with increase in tip ***-equation models for correlating stage characteristics with tip clearance are *** two designs,it is clearly evident that the conventional design shows better performance at moderate flow ***;near choke flow,tandem design gives better results primarily because of the increase in throat *** point flow rate also seems to drop for tandem compressor resulting in increased range of operation.

关键词： tandem blade conventional compressor inducer exducer numerical simulation

Multi-Mode Frequency Reconfigurable Conformal Antenna for Modern Electronic Systems

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Computers, Materials & Continua 2022年第11期73卷 3861-3877页

作者： Abir Zaidi Esraa Mousa Ali Abdullah G.Alharbi salah ud-din khan Mohammad Alsharef Mohammed S.Alzaidi Sherif S.M.Ghoneim Laboratory EEA&TI Faculty of Science and Techniques(FSTM)MohammediaHassan II UniversityCasablancaMorocco Faculty of Aviation Sciences Amman Arab UniversityAmman11953Jordan Department of Electrical Engineering Faculty of EngineeringJouf UniversitySakaka42421Saudi Arabia Sustainable Energy Technologies Center College of EngineeringKing Saud UniversityP.O.Box 800Riyadh11421Saudia Arabia Electrical Engineering Department College of EngineeringTaif UniversityP.O.Box 11099Taif21944Saudi Arabia

The article presents a miniaturized monopole antenna dedicated to modern flexible electronic *** antenna combines three fundamental properties in a single ***,it is characterized by a compact size compared to the state-of-the-art literature with an overall size of 18×18×0.254 mm3,secondly,the proposed antenna integrates the reconfigurability function of frequency,produced by means of a Positive-IntrinsicNegative(PIN)diode introduced into the radiating ***,the antenna is able to switch between different frequencies and different modes,making it suitable to meet the ever-changing demands of communication ***,the antenna is equipped by the property of *** fact,a conformability test is performed and has demonstrated the stability of the antenna performance under normal and bending ***,in order to demonstrate the potential of the proposed antenna,a comparison between the simulated and measured results is made and turned out to be a strong agreement,making the antenna an excellent candidate for future miniaturized rigid and conformal devices.

关键词： Monopole antenna frequency reconfigurable co-planar waveguide(CPW)fed flexible electronics compact size

Stability Control of Stretch-Twist-Fold Flow by Using Numerical Methods

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World Journal of Mechanics 2012年第6期2卷 334-338页

作者： Shahab ud-din khan Yonglu Shu salah ud-din khan Department of Mathematics and Statistics Chongqing University Chongqing China Sustainable Energy Technologies Center King Saud University Riyadh KSA

In this study, the multistep method is applied to the STF system. This method has been tested on the STF system, which is a three-dimensional system of ODE with quadratic nonlinearities. A computer based Matlab program has been developed in order to solve the STF system. Stable and unstable position of the system has been analyzed graphically and finally a comparison as well as accuracy between two-step sizes with detail. Newton’s method has been applied to show the best convergence of this system.

关键词： STF System Chaos Modified Method Fixed Point Iteration Method Newton’s Method

Detailed investigation of optimized alkali catalyzed transesterification of Jatropha oil for biodiesel production

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Journal of Energy Chemistry 2015年第3期24卷 331-336页

作者： Waqas Ahmed Muhammad Faizan Nazar Syed Danish Ali Usman Ali Rana salah ud-din khan National Centre for Physics Quaid-i-Azam University Campus Office of Research Innovation and CommercializationUniversity of Gujrat Department of Chemistry University of Gujrat Sustainable Energy Technologies (SET) Center College of EngineeringPO-Box 800King Saud University

The non-edible oils are believed to be one of the major feedstock for the production of biodiesel in *** the present study,we investigated the production of Jatropha oil methyl esters（JOMEs） via alkali-catalyzed transesterification *** biophysical characteristics of Jatropha oil were found within the optimal range in accordance with ASTM standards as a substitute diesel *** chemical composition and production yield of as-synthesized biodiesel were confirmed by various analytical techniques such as FT-IR,1H NMR,13 C NMR and gas chromatography coupled with mass spectrometry.A high percentage conversion,～96.09%,of fatty acids into esters was achieved under optimized transesterification conditions with 6 ：1 oil to methanol ratio and 0.9 wt% Na OH for 50 min at ～60°***,twelve fatty acids methyl esters（FAME） were quantified in the GC/MS analysis and it was interesting to note that the mass fragmentation pattern of saturated,monounsaturated and diunsaturated FAME was comparable with the literature reported values.

关键词： Jatropha oil methyl esters transesterification biodiesel fuel gas chromatography mass spectrometry

基于RELAP5的CFETR氦冷陶瓷增殖包层模块热工安全分析

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原子能科学技术 2017年第10期51卷 1778-1784页

作者：汪键宋云涛雷明准刘素梅郭超徐坤 salah ud-din khan 中国科学技术大学核科学技术学院安徽合肥230022 中国科学院等离子体物理研究所安徽合肥230031

本文对中国聚变工程实验堆(CFETR)氦冷陶瓷增殖(HCCB)包层进行热工安全分析。采用大型反应堆瞬态分析程序RELAP5对HCCB包层建模,并进行稳态分析和假设事故的模拟。计算结果表明,CFETR HCCB包层在真空室内氦气泄漏和增殖区盒内氦气泄漏... 详细信息

本文对中国聚变工程实验堆(CFETR)氦冷陶瓷增殖(HCCB)包层进行热工安全分析。采用大型反应堆瞬态分析程序RELAP5对HCCB包层建模,并进行稳态分析和假设事故的模拟。计算结果表明,CFETR HCCB包层在真空室内氦气泄漏和增殖区盒内氦气泄漏事故中均未出现结构材料熔化,同时各部分的压强变化情况均未超出设计阈值,包层系统在事故发生后均能有效快速地排出余热。CFETR HCCB包层的设计满足热工安全方面的要求。

关键词： RELAP5 中国聚变工程实验堆氦冷包层模块热工安全事故

Limits of Depth: Over-Smoothing and Over-Squashing in GNNs

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Big Data Mining and Analytics 2024年第1期7卷 205-216页

作者： Aafaq Mohi ud din Shaima Qureshi Department of Computer Science and Engineering National Institute of Technology SrinagarSrinagar 190006India

Graph Neural Networks(GNNs)have become a widely used tool for learning and analyzing data on graph structures,largely due to their ability to preserve graph structure and properties via graph representation ***,the effect of depth on the performance of GNNs,particularly isotropic and anisotropic models,remains an active area of *** study presents a comprehensive exploration of the impact of depth on GNNs,with a focus on the phenomena of over-smoothing and the bottleneck effect in deep graph neural *** research investigates the tradeoff between depth and performance,revealing that increasing depth can lead to over-smoothing and a decrease in performance due to the bottleneck *** also examine the impact of node degrees on classification accuracy,finding that nodes with low degrees can pose challenges for accurate *** experiments use several benchmark datasets and a range of evaluation metrics to compare isotropic and anisotropic GNNs of varying depths,also explore the scalability of these *** findings provide valuable insights into the design of deep GNNs and offer potential avenues for future research to improve their performance.

关键词： Graph Neural Networks(GNNs) learning on graphs over-smoothing over-squashing isotropic-GNNs anisotropic-GNNs

Hematobiochemical and histopathological alterations in Nile Tilapia(Oreochromis niloticus)exposed to ethidium bromide:The protective role of Spirulina platensis

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Aquaculture and Fisheries 2024年第1期9卷 93-103页

作者： Sabreen Abdullah Mervat Naguib Alaa El-din salah El-din Alaa El-din H.Sayed Zoology Department Faculty of ScienceAswan UniversityAswan81528Egypt Zoology Department Faculty of ScienceAssuit UniversityAssiut71516Egypt

Ethidium bromide(EtBr)is one of the contaminants recorded in aquatic environments whose effects have been investigated;however,there is still limited knowledge about its *** study examined the potential protective effects of Spirulina platensis(SP)against the effects of EtBr toxicity in the Nile tilapia(Oreochromis niloticus)*** were divided to five groups,viz.,a control and four treatment groups of low-dose EtBr(10μg/L),low-dose EtBr with SP(10μg/L EtBr+200 mg/L SP),high-dose EtBr(100μg/L),and high-dose EtBr with SP(100μg/L EtBr+200 mg/L SP);the exposure period was 2 *** and high doses of EtBr induced alterations in some hematological,biochemical,and histopathological *** hepatocytes,degenerated area,vacuolated hepatocytes,pyknotic nuclei,constricted and dilated blood sinusoids,and infiltration of inflammatory cells were *** peroxidation concentration was not significantly different in groups exposed to low doses of EtBr and EtBr with SP,but it was increased in groups exposed to high doses of EtBr and EtBr with SP,compared with the control *** feeding with SP,most histological and histochemical parameters restored to normal ***,SP may possess the ability to preserve the structural integrity of the hepatic and renal membranes.

关键词： Ethidium bromide Spirulina platensis Oreochromis niloticus Liver Lipid peroxidation

Fabrication of MXene-Bi_(2)WO_(6)heterojunction by Bi_(2)Ti_(2)O_(7)hinge for extraordinary LED-light-driven photocatalytic performance

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Nano Research 2024年第6期17卷 4729-4736页

作者： Zhiwen Li Liangliang Xu Zaheer ud din Babar Ali Raza Yifei Zhang Xinrui Gu Yu-Xin Miao Zhen Zhao Gao Li Institute of Catalysis for Energy and Environment College of Chemistry and Chemical EngineeringShenyang Normal UniversityShenyang 110034China State Key Laboratory of Catalysis Dalian Institute of Chemical PhysicsChinese Academy of SciencesDalian 116023China Scuola Superiore Meridionale(SSM) University of Naples Federico IILargo S.Marcellino1080138Italy Department of Chemical and Biomolecular Engineering Korea Advanced Institute of Science and Technology(KAIST)Daejeon 34141Republic of Korea University of Chinese Academy of Sciences Beijing 100049China

Heterojunction composites with intimate interfaces can shorten the diffusion distance,which leads to a shorter path for photogenerated carriers,thereby increasing photocatalytic ***,we report the fabrication of Ti_(3)C_(2)-Bi_(2)WO_(6)(TC-BW)heterojunctions hinged by Bi_(2)Ti_(2)O_(7)joints via an in situ hydrothermal reaction of Ti_(3)C_(2)in the presence of Na_(2)WO_(4)and Bi(NO_(3))_(3).The TC-BW was characterized using X-ray diffraction(XRD),scanning transmission electron microscopy(STEM),and Raman ***-BW showed superior photocatalytic activity(productivity over 15TC-WB reaches up to 5.0 mmolreacted BA·gcat.^(−1)·h^(−1))in the oxidation of benzyl alcohol using light-emitting diode(LED)light,arising from the surface defects and intimate heterojunction interface between the Ti_(3)C_(2)MXene and Bi_(2)WO_(6)***-BW heterojunctions provide an enhanced separation efficiency of photogenerated charges,which in turn yields superior photocatalytic ***,it is well substantiated by density functional theory(DFT)*** summary,this study elucidates the preparation of heterojunction composites with intimate interfaces for highly efficient photooxidation.

关键词： MXene-Bi_(2)WO_(6) heterojunction LED-light-driven photocatalysis Bi_(2)Ti_(2)O_(7) photooxidation

Straw return influences the structure and functioning of arbuscular mycorrhizal fungal community in a rice-wheat rotation system

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Pedosphere 2024年第2期34卷 339-350页

作者： Silong ZHAI Junjie XIE Zongyi TONG Bing YANG Weiping CHEN Roger TKOIDE Yali MENG Xiaomin HUANG Atta Mohi ud din Changqing CHEN Haishui YANG College of Agriculture Nanjing Agricultural UniversityNanjing 210095China Department of Biology Brigham Young UniversityProvo UT 84602USA Jiangsu Key Laboratory of Crop Genetics and Physiology/Jiangsu Key Laboratory of Crop Cultivation and Physiology Agricultural College of Yangzhou UniversityYangzhou 225009China National Research Center of Intercropping The Islamia University of BahawalpurBahawalpur 63100Pakistan Jiangsu Collaborative Innovation Center for Modern Crop Production Nanjing Agricultural UniversityNanjing 210095China

Straw return is a sustainable soil fertility-building practice,which can affect soil microbial ***,how straw return affects arbuscular mycorrhizal fungi(AMF)is not well ***,we studied the impacts of different straw management treatments over eight years on the structure and functioning of AMF communities in a rice-wheat rotation *** straw management treatments included no tillage with no straw(NTNS),rotary tillage straw return(RTSR),and ditch-buried straw return(DBSR).The community structure of AMF was characterized using high-throughput sequencing,and the mycorrhizal functioning was quantified using an in situ mycorrhizal-suppression *** straw management treatments formed unique AMF community structure,which was closely related to changes in soil total organic carbon,available phosphorus,total nitrogen,ammonium,and *** compared with NTNS,RTSR significantly increased Shannon diversity in 0–10 cm soil layer,while DBSR increased it in 10–20 cm soil layer;DBSR significantly increased hyphal length density in the whole ploughing layer(0–20 cm),but RTSR only increased it in the subsurface soil layer(10–20 cm).The mycorrhizal responses of shoot biomass and nutrient(N and P)uptake were positive under both straw return treatments(RTSR and DBSR),but negative under *** community composition of AMF was significantly correlated to hyphal length density,and the latter was further a positive predictor for the mycorrhizal responses of plant growth and nutrient *** findings suggest that straw return can affect AMF community structure and functioning,and farmers should manage mycorrhizas to strengthen their beneficial effects on crop production.

关键词： community structure hyphal length density shoot biomass shoot N uptake shoot P uptake soil physicochemical properties straw management tillage

Context-Aware Collaborative Filtering Framework for Rating Prediction Based on Novel Similarity Estimation

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Computers, Materials & Continua 2020年第5期63卷 1065-1078页

作者： Waqar Ali salah ud din Abdullah Aman khan Saifullah Tumrani Xiaochen Wang Jie Shao School of Computer Science and Engineering University of Electronic Science and Technology of ChinaChengdu611731China Faculty of Information Technology The University of LahoreLahore54000Pakistan Sichuan Artificial Intelligence Research Institute Yibin644000China

Recommender systems are rapidly transforming the digital world into intelligent information *** valuable context information associated with the users’prior transactions has played a vital role in determining the user preferences for items or rating *** has been a hot research topic in collaborative filtering-based recommender systems for the last two *** paper presents a novel Context Based Rating Prediction(CBRP)model with a unique similarity scoring estimation *** proposed algorithm computes a context score for each candidate user to construct a similarity pool for the given subject user-item pair and intuitively choose the highly influential users to forecast the item *** context scoring strategy has an inherent capability to incorporate multiple conditional factors to filter down the most relevant *** with traditional similarity estimation methods,CBRP makes it possible for the full use of neighboring collaborators’choice on various *** conduct experiments on three publicly available datasets to evaluate our proposed method with random user-item pairs and got considerable improvement in prediction accuracy over the standard evaluation ***,we evaluate prediction accuracy for every user-item pair in the system and the results show that our proposed framework has outperformed existing methods.

关键词： Recommender system context-based similarity estimation rating prediction collaborative filtering