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测量线路中电阻的新方法

国外计量 1985年第3期 54-55页

作者： m.rehman 文传鸿

一、前言电阻元件在复合网络中的测量,是指电阻在线路中的直接测量。这种测量方法特别适应于混合式集成电路的测量。近几年来,已经提出过一些用于全电阻器回路中测量线路中的电阻的新技术。但是,所提出的方法的准确度,由

关键词：测量线路电阻器复合网络电阻电阻抗电桥电路

Facile synthesis of samarium and cerium doped double perovskite cobaltite with enhanced dielectric response

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Journal of Rare Earths 2024年第7期42卷 1317-1327,I0005页

作者： Yasir Abbas m.Kamran m.Anis-ur-rehman Applied Thermal Physics Laboratory Department of PhysicsCOMSATS University IslamabadIslamabad 45550Pakistan

The investigation of Sm-Ce doping on structure,conduction,and dielectric response of Bi_(2)Ca_(2-2x)Sm_(x)CexCoO_(6)(x=0.000,0.025,0.050,0.075)(BCSCCO)are *** the specimens were synthesized by a facile synthesis technique named the co-precipitation route.X-ray diffraction(XRD)reveals that BCSCCO crystallizes into one phase with space group P21/*** crystallite size,dislocation density,lattice parameters,lattice strain,unit cell volume,and bulk density were determined using XRD *** structural properties of Bi_(2)Ca_(2)CoO_(6)were examined using calculations based on the density functional *** and experimental values discrepancy is less than 1%.A scanning electron microscope was used for performing a microstructural *** SEm images demonstrate the homogeneous distribution of grains with a range of sizes(0.054-0.090μm).The alternating current(ac)conductivity,dielectric permittivity,and tangent loss were also studied as a function of frequency(20 Hz-3 mHz)at different temperatures(100-500℃).All synthesized samples were examined using non-linear Debye's function to determine their spreading factor and relaxation *** specimen with the lowest crystallite size(∼23 nm)exhibits a high dielectric permittivity(∼3.80×10^(6)).The conduction mechanism was examined in the studied samples with the use of Jonscher's power *** power law indicates that the BCSCCO(x=0.000,0.025)follows correlated barrier hopping,whereas the x=0.050 and 0.075 compositions follow non-overlapping polaron *** studied specimen Bi_(2)Ca_(1.9)0Sm_(0.05)0Ce_(0.05)_(0)CoO_(6)with the highest density(∼5.65 g/cm^(3))displays a high electrical conductivity(∼46.1 S/cm).These findings correspond to those published for ceramics made from calcium cobaltite using solid-state reactions(5.0-26.0 S/cm).

关键词： Bismuth calcium samarium cerium cobaltite (BCSCCO) Spreading factor Conduction mechanism Rare earths

Conjugated microporous polymer membranes for chemical separations

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Fabrication and application prospects of Pr-Fe-B/Alnico nanocomposite alloys

中国化学工程学报（英文版） 2022年第5期

作者： Zongyao Zhou Zhen Li Lubna m.rehman Zhiping Lai

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Journal of Rare Earths 2024年第9期42卷 1717-1723,I0003页

作者： Hui Liang Sajjad Ur rehman Ruibiao Zhang Yongqiang Deng Haihua Liu munan Yang National Rare Earth Functional materials Innovation Center College of Rare EarthsJiangxi University of Science and TechnologyGanzhou341000China Zhejiang Tiantong Electronic Information materials Research Institute Co. Ltd.Haining314400China

The potentials of rare earth-based nanocomposite alloys have never been realized due to strict microstructural *** to the easy demagnetization it is challenging to increase the soft magnetic phase *** avoid the easy demagnetization,Pr-Fe-B/Alnico magnets were fabricated and reported in this *** content of the Alnico phase is increased from 0 to 25 wt%,while the content of Pr element is reduced to below the sub-stoichiometry of the 2:14:1 main *** maximum magnetic energy product,which is the figure-of-merit for permanent magnets,is increased from 122 kJ/m^(3) for the standard alloy to 146 kJ/m^(3) for the alloy with 15 wt% Alnico which shows a significant improvement considering the fact that the Curie point of the magnet is also increased by~66 *** special microstructure contains distinctly and heterogeneously distributed 2:14:1 and Alnico *** dimensions of neither the 2:14:1 nor the Alnico phases meet the dimensional requirements of the nanocomposite magnets,but still the smooth demagnetization curves are noted for the *** behavior of effective anisotropy,the performance of the magnets in applied magnetic field and the magnetic interactions among the various constituent grains were quantitatively studied by reversible susceptibility,irreversible susceptibility and re coil loop *** study may provide some guiding principles for the development of nanocomposite magnetic alloys with excellent magnetic properties by using much less RE elements.

关键词： Composite alloys High performance magnets magnetic properties Alnico alloys Rare earth magnets

Symmetries,optimal system,exact and soliton solutions of(3+1)-dimensional Gardner-KP equation

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Journal of Ocean Engineering and Science 2024年第2期9卷 178-190页

作者： Amjad Hussain Ashreen Anjum m.Junaid-U-rehman Ilyas Khan mariam A.Sameh Amnah S.Al-Johani Department of mathematics Quaid-I-Azam University 45320Islamabad 44000Pakistan Department of mathematics College of Science Al-ZulfiMajmaah UniversityAl-MajmaahP.O Box 66Majmaah 11952Saudi Arabia Electrical Engineering Department Faculty of Engineering and TechnologyFuture University in EgyptNew Cairo 11845Egypt mathematics Department Faculty of ScienceUniversity of TabukTabukSaudi Arabia

In this research article,the(3+1)-dimensional nonlinear Gardner-Kadomtsov-Petviashvili(Gardner-KP)equation which depicts the nonlinear modulation of periodic waves,is analyzed through the Lie group-theoretic *** the Lie invariance condition,we find the symmetry *** pro-posed model yields eight-dimensional Lie ***,an optimal system of sub-algebras is com-puted,and similarity reductions are *** considered nonlinear partial differential equation is re-duced into ordinary differential equations(ODEs)by utilizing the similarity transformation method(STm),which has the benefit of yielding a large number of accurate traveling wave *** ODEs are further solved to get closed-form solutions of the Gardner-KP equation in some cases,while in other cases,we use the new auxiliary equation method to get its soliton *** evolution profiles of the obtained solutions are examined graphically under the appropriate selection of arbitrary parameters.

关键词： Gardner-KP equation Lie symmetry analysis Optimal system New auxiliary equation method Solitary wave solutions

Simultaneously enhancing coercivity and remanence of hot-deformed Nd-Fe-B magnets by flake copper powder assisted DyF_(3) interflake addition

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Journal of Rare Earths 2024年第7期42卷 1282-1288,I0003页

作者： Yikuan Hu Jiajie Li Shengyu Sun Shuwei Zhong munan Yang Xiaoqiang Yu Sajjad Ur rehman Xi Yu Jiangxi Key Laboratory for Rare Earth magnetic materials and Devices College of Rare EarthsJiangxi University of Science and TechnologyGanzhou341000 National Rare Earth Functional materials Innovation Center Ganzhou341000China Ganzhou Fortune Electronic Ltd. Ganzhou341000China

It is still a challenge to simultaneously enhance coercivity(H_(cj))and remanence(J_(r))of hot-deformed Nd-Fe-B magnet due to the coercivity-remanence trade-off ***,we achieved this balance between H_(cj)and Jr by flake Cu powder assisted DyF_(3)interflake *** Hcj increases from 1218 to 1496 kA/m and Jr increases from 1.32 to 1.34 T compared with the original *** show that the width of coarse grain layers reduces because of the introduction of flake Cu,which increases the contact areas of the adjacent grains at ribbon interfaces and suppresses the excessive growth of *** stronger degree of texture and higher density compared with the original magnet should take the responsibility for the increase of J_(r).Additionally,the aggregation regions of rare earth rich(RE-rich)phase reduce and the betterment of the microstructure is another reason for the enhancement of Jr in the flake Cu aided DyF_(3)hot-deformed *** strategy of using flake powder additives provides a promising method for optimizing microstructure and enhancing magnetic properties of hot-deformed Nd-Fe-B magnets.

关键词： Rare earths Nd-Fe-B Hot-deformed magnet Flake powder Interflake addition Remanence

Deploying Hybrid Ensemblemachine Learning Techniques for Effective Cross-Site Scripting (XSS) Attack Detection

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Computers, materials and Continua 2024年第1期81卷 707-748页

作者： Bacha N.U. Lu S. Ur rehman A. Idrees m. Ghadi Y.Y. Alahmadi T.J. School of Cyber Science and Engineering Huazhong University of Science and Technology Wuhan 430073 China Department of Computer Science and Engineering University of Engineering and Technology Lahore 54000 Pakistan Department of Computer Science and Software Engineering Al Ain University Al Ain Abu Abu Dhabi 12555 United Arab Emirates Department of Information Systems College of Computer and Information Sciences Princess Nourah bint Abdulrahman University Riyadh 84428 Saudi Arabia

Cross-Site Scripting (XSS) remains a significant threat to web application security, exploiting vulnerabilities to hijack user sessions and steal sensitive data. Traditional detection methods often fail to keep pace with the evolving sophistication of cyber threats. This paper introduces a novel hybrid ensemble learning framework that leverages a combination of advanced machine learning algorithms-Logistic Regression (LR), Support Vector machines (SVm), eXtreme Gradient Boosting (XGBoost), Categorical Boosting (CatBoost), and Deep Neural Networks (DNN). Utilizing the XSS-Attacks-2021 dataset, which comprises 460 instances across various real-world trafficrelated scenarios, this framework significantly enhances XSS attack detection. Our approach, which includes rigorous feature engineering and model tuning, not only optimizes accuracy but also effectively minimizes false positives (FP) (0.13%) and false negatives (FN) (0.19%). This comprehensive methodology has been rigorously validated, achieving an unprecedented accuracy of 99.87%. The proposed system is scalable and efficient, capable of adapting to the increasing number of web applications and user demands without a decline in performance. It demonstrates exceptional real-time capabilities, with the ability to detect XSS attacks dynamically, maintaining high accuracy and low latency even under significant loads. Furthermore, despite the computational complexity introduced by the hybrid ensemble approach, strategic use of parallel processing and algorithmtuning ensures that the system remains scalable and performs robustly in real-time applications. Designed for easy integration with existing web security systems, our framework supports adaptable Application Programming Interfaces (APIs) and a modular design, facilitating seamless augmentation of current defenses. This innovation represents a significant advancement in cybersecurity, offering a scalable and effective solution for securing modern web applications a

关键词： Cross-site scripting hybrid learning machine learning stacking ensemble learning XSS detection

Deep Insight of Design,mechanism,and Cancer Theranostic Strategy of Nanozymes

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Nano-micro Letters 2024年第2期16卷 165-217页

作者： Lu Yang Shuming Dong Shili Gai Dan Yang He Ding Lili Feng Guixin Yang Ziaur rehman Piaoping Yang Key Laboratory of Superlight materials and Surface Technology Ministry of EducationCollege of Materials Science and Chemical EngineeringHarbin Engineering UniversityHarbin 150001People’s Republic of China Yantai Research Institute Harbin Engineering UniversityYantai 264000People’s Republic of China Key Laboratory of Green Chemical Engineering and Technology of Heilongjiang Province College of Material Science and Chemical EngineeringHarbin University of Science and TechnologyHarbin 150040People’s Republic of China Department of Chemistry Quaid-i-Azam UniversityIslamabad 45320Pakistan

Since the discovery of enzyme-like activity of Fe3O4 nanoparticles in 2007,nanozymes are becoming the promising substitutes for natural enzymes due to their advantages of high catalytic activity,low cost,mild reaction conditions,good stability,and suitable for large-scale ***,with the cross fusion of nanomedicine and nanocatalysis,nanozyme-based theranostic strategies attract great attention,since the enzymatic reactions can be triggered in the tumor microenvironment to achieve good curative effect with substrate specificity and low side ***,various nanozymes have been developed and used for tumor *** this review,more than 270 research articles are discussed systematically to present progress in the past five ***,the discovery and development of nanozymes are ***,classification and catalytic mechanism of nanozymes are ***,activity prediction and rational design of nanozymes are focused by highlighting the methods of density functional theory,machine learning,biomimetic and chemical ***,synergistic theranostic strategy of nanozymes are ***,current challenges and future prospects of nanozymes used for tumor theranostic are outlined,including selectivity,biosafety,repeatability and stability,in-depth catalytic mechanism,predicting and evaluating activities.

关键词： Nanozymes Classification Prediction and design Catalytic mechanism Tumor theranostics

Seed Priming with Potassium Nitrate Can Enhance Salt Stress Tolerance in maize

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Phyton-International Journal of Experimental Botany 2024年第8期93卷 1819-1838页

作者： Bushra rehman Asma Zulfiqar Houneida Attia Rehana Sardar muneera A.Saleh Khalid H.Alamer Ibtisam m.Alsudays Faisal mehmood Qamar uz Zaman Institute of Botany University of the PunjabLahore54590Pakistan Department of Biology College of ScienceTaif UniversityTaif21944Saudi Arabia Department of Botany Emerson UniversityMultan60000Pakistan Biological Sciences Department Faculty of Science and ArtsKing Abdulaziz UniversityRabigh21911Saudi Arabia Department of Biology College of ScienceQassim UniversityBurydah52571Saudi Arabia Department of Chemistry Sciences The University of LahoreLahore54590Pakistan Department of Environmental Sciences The University of LahoreLahore54590Pakistan

Salinity is a major abiotic stress that hinders plant development and productivity and influences agricultural *** priming is a technique used to boost germination and seedling growth under abiotic stress.A pot experiment was conducted to evaluate the impact of seed priming with potassium nitrate(KNO_(3))at various levels(0%,0.50%,1.00%and 1.50%)under salt stress(0,75,100 mm NaCl)on two maize verities(mNH360 and 30T60)for the growth,development and metabolic attributes results revealed that in maize variety mNH360,KNO_(3)priming’s significantly enhanced growth parameters than in maize variety 30T60 under control and salt-stressed *** with KNO_(3)enhanced carotenoids and total chlorophyll in the 30T60 variety that protected the maize plants from salt ***,it was shown that priming with 1.00%KNO_(3)acts as safeguarded to protect them from oxidative damage by salt stress minimizing reactive oxygen species(ROS)formation through increased levels of malondialdehyde(mDA),catalase(CAT),peroxidase(POD),ascorbate peroxidase(APX),and total soluble *** findings of the present study confirm that the use of the KNO_(3)seed priming technique is a lowcost,environmentally friendly technique for mitigating adverse impacts of salt stress in maize crops by activating the antioxidant defense system and improving chlorophyll and osmolyte contents.

关键词： Salinity Zea mays antioxidant enzymes growth seedlings oxidative damage