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Frontiers of Structural and Civil Engineering 2021年第1期15卷 124-135页

作者： Dammika P.K.WELLALA Ashish Kumer SAHA Prabir Kumar SARKER Vinod RAJAYOGAN School of Civil and Mechanical Engineering Curtin UniversityPerthWA 6845Australia Regional technical manager HolcimPerthWA 6004Australia

This paper presents the fresh and hardened properties of high-strength concrete comprising byproduct fine crushed aggregates(FCAs)sourced from the crushing of three different types of rocks,namely granophyre,basalt,and *** lowest void contents of the combined fine aggregates were observed when 40%to 60%of natural sand is replaced by the *** the replacement of 40%FCAs,the slump and bleeding of concrete with a water-to-cement ratio of 0.45 decreased by approximately 15%and 50%,respectively,owing to the relatively high fines content of the *** 28 d compressive strength of concrete was 50 MPa when 40%FCAs were *** slight decrease in tensile strength from the FCAs is attributed to the flakiness of the *** correlations between the splitting tensile and compressive strengths of normal concrete provided in the AS 3600 and ACI 318 design standards are applicable for concrete using the FCAs as partial replacement of *** maximum 56 d drying shrinkage is 520 microstrains,which is significantly less than the recommended limit of 1000 microstrains by AS 3600 for ***,the use of these byproduct FCAs can be considered as a sustainable alternative option for the production of high-strength green concrete.

关键词： fine crushed aggregates quarry dust compressive strength splitting tensile strength drying shrinkage

Bimetallic Single‑Atom Catalysts for Water Splitting

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Nano-Micro Letters 2025年第1期17卷 1-45页

作者： Megha A.Deshmukh Aristides Bakandritsos Radek Zbořil Nanotechnology Centre Centre for Energy and Environmental TechnologiesVŠB–Technical University of Ostrava17.listopadu 2172/1570800 Ostrava‑PorubaCzech Republic Regional Centre of Advanced Technologies and Materials Czech Advanced Technology and Research Institute(CATRIN)Palacky University OlomoucŠlechtitelů241/2778371 Olomouc–HoliceCzech Republic

Green hydrogen from water splitting has emerged as a critical energy vector with the potential to spearhead the global transition to a fossil fuel-independent *** field of catalysis has been revolutionized by single-atom catalysts(SACs),which exhibit unique and intricate interactions between atomically dispersed metal atoms and their ***,bimetallic SACs(bimSACs)have garnered significant attention for leveraging the synergistic functions of two metal ions coordinated on appropriately designed *** offer an avenue for rich metal–metal and metal–support cooperativity,potentially addressing current limitations of SACs in effectively furnishing transformations which involve synchronous proton–electron exchanges,substrate activation with reversible redox cycles,simultaneous multi-electron transfer,regulation of spin states,tuning of electronic properties,and cyclic transition states with low activation *** review aims to encapsulate the growing advancements in bimSACs,with an emphasis on their pivotal role in hydrogen generation via water *** subsequently delve into advanced experimental methodologies for the elaborate characterization of SACs,elucidate their electronic properties,and discuss their local coordination ***,we present comprehensive discussion on the deployment of bimSACs in both hydrogen evolution reaction and oxygen evolution reaction,the two half-reactions of the water electrolysis process.

关键词： Single-atom catalysts Single-atom dimers Hydrogen evolution Oxygen evolution Water splitting

ICA-Net: improving class activation for weakly supervised semantic segmentation via joint contrastive and simulation learning

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Optoelectronics Letters 2025年第3期 188-192页

作者： YE Zhuang LIU Ruyu SUN Bo School of Information Engineering Chengdu Aviation Vocational and Technical College School of Computer Science and Engineering Hangzhou Normal University Quanzhou Institute of Equipment Manufacturing Haixi Institutes Chinese Academy of Sciences

In the field of optoelectronics, certain types of data may be difficult to accurately annotate, such as high-resolution optoelectronic imaging or imaging in certain special spectral ranges. Weakly supervised learning can provide a more reliable approach in these situations. Current popular approaches mainly adopt the classification-based class activation maps (CAM) as initial pseudo labels to solve the task.

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Two-dimensional ultrathin MoS2-modified black Ti^3+-TiO2 nanotubes for enhanced photocatalytic water splitting hydrogen production

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Journal of Energy Chemistry 2020年第4期29卷 188-194页

作者： Wei Ou Jiaqi Pan Yanyan Liu Shi Li Hongli Li Weijie Zhao Jingjing Wang Changsheng Song Yingying Zheng Chaorong Li Key Laboratory of Optical field Manipulation of Zhejiang Province and Key Laboratory of ATMMT ministry of EducationDepartment of PhysicsZhejiangSci-Tech UniversityHangzhou 310018ZhejiangChina School of Medical and Pharmaceutical Engineering Taizhou Vocational&Technical CollegeTaizhou 318000ZhejiangChina

Two-dimensional (2D) ultrathin MoS2-modified black Ti^3+-TiO2 nanotubes were fabricated using an electrospinning-hydrothermal treatment-reduction *** TiO2 nanotubes were fabricated via ***,2D MoS2 lamellae were grown on the surface of the nanotubes and Ti^3+/Ov ions were introduced by *** photocatalytic performance of the 2D MoS2/Ti^3+-TiO2 nanotubes was^15 times better than that of *** HER enhancement of the MoS2/Ti^3+-TiO2 nanotubes can be attributed to the Pt-like behavior of 2D MoS2 and the presence of Ti^3+-ions,which facilitated the quick diffusion of the photogenerated electrons to water,reducing the H2 activation *** presence of Ov ions in the nanotubes and their hollow structure increased their solar utilization.

关键词： 2D MoS2 TiO2 nanotubes Ti^3+self-doping Photocatalytic hydrogen production

USB data acquisition solution

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国外电子测量技术 2007年第2期26卷 6-9页

作者： Serges Lemo Zhu June Data Acquisition Product Marketing Engineer NI China technical Marketing manager

1 IntroductionIn recent years, USB has evolved from a simple, low-speed peripheral bus for mice, keyboards, and other computer accessories to the bus of choice for more demanding applications, including data acquisiti... 详细信息

关键词： USB 数据获取方法计算机

Keyword Extraction from Scientific Research Projects Based on SRP-TF-IDF

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Chinese Journal of Electronics 2021年第4期30卷 652-657页

作者： WANG Zhuohao WANG Dong LI Qing Institute of Scientific and technical Information of China

Keyword extraction by Term frequencyInverse document frequency(TF-IDF) is used for text information retrieval and mining in many domains, such as news text, social contact text, and medical ***, keyword extraction in special domains still needs to be improved and optimized, particularly in the scientific research field. The traditional TF-IDF algorithm considers only the word frequency in documents, but not the domain characteristics. Therefore, we propose the Scientific research project TF-IDF(SRP-TF-IDF) model,which combines TF-IDF with a weight balance algorithm designed to recalculate candidate keywords. We have implemented the SRP-TF-IDF model and verified that our method has better precision, recall, and F1 score than the traditional TF-IDF and TextRank methods. In addition, we investigated the parameter of our weight balance algorithm to find an optimal value for keyword extraction from scientific research projects.

关键词： extraction TF-IDF Scientific research project Word vector

General investigation for longitudinal wave propagation under magnetic field effect via nonlocal elasticity

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Applied Mathematics and Mechanics(English Edition) 2015年第10期36卷 1305-1318页

作者： U.GVEN Department of Mechanical Engineering Yildiz Technical University

In this paper, the propagation of longitudinal stress waves under a longitu- dinal magnetic field is addressed using a unified nonlocal elasticity model with two scale coefficients. The analysis of wave motion is mainly based on the Love rod model. The effect of shear is also taken into account in the framework of Bishop＇s correction. This analysis shows that the classical theory is not sufficient for this subject. However, this unified nonlocal elasticity model solely used in the present study reflects in a manner fairly realistic for the effect of the longitudinal magnetic field on the longitudinal wave propagation.

关键词： Rayleigh-Bishop rod nonlocal elasticity magnetic field wave propagation

A Test Study of 50% Lightning Impulse Breakdown Voltage on Rod-Plane Gap with Two-Phase Mixture of Gas and Solid Particles

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Plasma Science and Technology 2007年第6期9卷 695-697页

作者：何正浩许怀丽白金余福胜胡枫李劲 Pulsed Magnetic field Lab Huazhong University of Science and TechnologyWuhan 430074China

A test study on 50% lightning impulse breakdown voltage in two-phase mixture of gas and solid particles has been carried out in a specially designed discharge cabinet. A mechanical sieve is set up for sifting different solid particles into the discharge space uniformly. The lightning impulse voltage according with international electro-technical commission （IEC） standard is applied to the electrodes inside the discharge cabinet by the rule of up-down method in a total of 40 times. The results showed that the 50% lightning impulse breakdown voltage in two-phase mixture of gas and solid particles has its own features and is much different from that in air.

关键词： solid particles two-phase mixture 50% breakdown voltage

Investigation into the effect of friction decay factor on the modelling and attenuation of stick-slip vibrations of oilwell drilling systems

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Petroleum 2022年第3期8卷 344-351页

作者： Mohammed Y.A.Alkaragoolee David Bryant technical Institute Baqubah Middle Technical UniversityIraq Faculty of Engineering&Informatics University of BradfordUK

The self-excited stick-slip oscillations of oilwell drillstrings are attributed to the nonlinear interaction between the drill-bit and the rock *** of more accurate models will lead to improved predictions allowing more potential for successful suppression of the drillstring vibrations,thus reducing damage to the drilling system,prevention of expensive failures and increased output from the *** this paper,the effect of the transition from static friction to Coulomb friction on modelling of stick-slip phenomenon of oil well drill string is investigated through an analysis of the so called‘decay factor’.Based on a distributed-lumped parameter model(DLPM)of the drilling system,the governing equations of motion for the system are *** using different values of decay factor(low,high and medium),the stick-slip vibrations of the drill string are validated against published data from full-scale drill *** results from the simulation show that lowering the decay factor increases the critical speed and thus reduces the propensity for stick slip ***,a reduction in the decay factor also has the effect of inducing worse stick-slip motion once the critical speed has been *** results indicate the wider impact of both correct modelling of the decay factor,but also the importance of correct characterisation of the mud viscosity and drill/well contact for more accurate selection of drilling parameters in the field.

关键词： Stribeck effect Stick-slip vibration Drillstring Distributed-lumped parameters model

Results of the Main Phase of Ion Separation in the Process of Plasma-Optical Mass Separation

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Plasma Science and Technology 2015年第10期17卷 862-868页

作者： V.M.BARDAKOV S.D.IVANOV A.V.KAZANTSEV N.A.STROKIN Institute for Physics and Technology Irkutsk State Technical University

This paper presents separation results of a mixture of nitrogen, argon and krypton ions in the process of plasma-optical mass separation on the POMS-E-3 separator model. We determined the behavior of the separation with a change in the value of magnetic field induction in the azimuthator and in the degree of compensation of the spatial charge in ion flows. An analysis is performed for experimental data by correlation with the results of a theoretical study and numerical experiments. The objectives of future experiments are outlined.

关键词： plasma-optical mass separation plasma accelerator trajectories spatial charge