检索结果-南通市图书馆

Melt flow,heat transfer and solidification in a flexible thin slab continuous casting mold with vertical-combined electromagnetic braking

在线全文

学校读者我要写书评

暂无评论

Journal of Iron and Steel Research International 2024年第2期31卷 401-415页

作者： lin Xu Ze-feng Han Christian Karcher En-gang Wang Key Laboratory of Electromagnetic Processing of Materials(Ministry of Education) Northeastern UniversityShenyang110819LiaoningChina Key Laboratory of Liaoning Province for Clean Combustion Power Generation and Heating Technology Shenyang Institute of EngineeringShenyang110136LiaoningChina Institute of Thermodynamics and Fluid Mechanics Technische Universität IlmenauIlmenau98684Germany

During continuous casting of steel slabs,the application of electromagnetic braking technology(EMBr)provides an effective tool to influence solidification by controlling the pattern of melt flow in the ***,the quality of the final product can be improved considerably.A new electromagnetic braking(EMBr)method,named vertical-combined electromagnetic braking(VC-EMBr),is proposed to be applied to a flexible thin slab casting(FTSC)*** evaluate the beneficial effects of the VC-EMBr,the melt flow,heat transfer,and solidification processes in the FTSC mold are studied by means of numerical *** detail,a Reynolds-averaged Navier–Stokes turbulence model together with an enthalpy-porosity approach was *** numerical findings are compared with respective simulations using the traditional *** results demonstrate that the application of the VC-EMBr contributes significantly to preventing relative slab *** contrast to the Ruler-EMBr,the additional vertical magnetic poles of the VC-EMBr preferentially suppress the direct impact of jet flow on the narrow face of FSTC mold and considerably diminish the level fluctuation near the meniscus *** instance,by applying a magnetic flux density of 0.3 T,the maximum amplitude of meniscus deflection reduces by about 80%.Moreover,the braking effect of the VC-EMBr effectively improves the homogeneity of temperature distribution in the upper recirculation region and increases the solidified shell thickness along the casting *** this basis,the newly proposed VC-EMBr shows a beneficial effect in preventing relative slab defects for FTSC thin slab continuous casting.

关键词： Electromagnetic braking Mold Melt flow Heat transfer Solidification

Hybrid pedestrian positioning system using wearable inertial sensors and ultrasonic ranging

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Defence Technology（防务技术） 2024年第3期33卷 327-338页

作者： lin Qi Yu Liu Chuanshun Gao Tao feng Yue Yu School of Communication and Information Engineering Chongqing University of Posts and TelecommunicationsChongqing 400065China Department of Land Surveying and Geo-Informatics The Hong Kong Polytechnic UniversityHong Kong 999077China

Pedestrian positioning system(PPS)using wearable inertial sensors has wide applications towards various emerging fields such as smart healthcare,emergency rescue,soldier positioning,*** performance of traditional PPS is limited by the cumulative error of inertial sensors,complex motion modes of pedestrians,and the low robustness of the multi-sensor collaboration *** paper presents a hybrid pedestrian positioning system using the combination of wearable inertial sensors and ultrasonic ranging(H-PPS).A robust two nodes integration structure is developed to adaptively combine the motion data acquired from the single waist-mounted and foot-mounted node,and enhanced by a novel ellipsoid constraint *** addition,a deep-learning-based walking speed estimator is proposed by considering all the motion features provided by different nodes,which effectively reduces the cumulative error originating from inertial ***,a comprehensive data and model dual-driven model is presented to effectively combine the motion data provided by different sensor nodes and walking speed estimator,and multi-level constraints are extracted to further improve the performance of the overall *** results indicate that the proposed H-PPS significantly improves the performance of the single PPS and outperforms existing algorithms in accuracy index under complex indoor scenarios.

关键词： Pedestrian positioning system Wearable inertial sensors Ultrasonic ranging Deep-learning Data and model dual-driven

A harmonic-wave bio-thermal method for continuous monitoring skin thermal conductivity and capillary perfusion rate

在线全文

学校读者我要写书评

暂无评论

Nano Research 2024年第5期17卷 4420-4427页

作者： Yuxin Ouyang Jie lin Jiajing Pei Rui Sui Di Liu Yanhui feng lin Qiu School of Energy and Environmental Engineering University of Science and Technology BeijingBeijing 100083China Ningbo Institute of Materials Technology and Engineering Chinese Academy of SciencesNingbo 315201China Beijing Synchrotron Radiation Facility Institute of High Energy PhysicsChinese Academy of SciencesBeijing 100049China Department of Chemistry Tsinghua UniversityBeijing 100084China Institute of Analysis and Testing Beijing Academy of Science and TechnologyBeijing 100089China

The revelation of thermal energy exchange mechanism of human body is challenging yet worthwhile,because it can clearly explain the changes in human symptoms and health ***,the heat transfer of the skin is significant because the skin is the foremost organ for the energy exchange between the human body and the *** order to diagnose the physiological conditions of human skin without causing any damage,it is necessary to use a non-invasive measurement technique by means of a conformal flexible *** harmonic method can minimize the thermal-induced injury to the skin due to its low heat generating properties.A novel type of computational theory assessing skin thermal conductivity,blood perfusion rate of capillaries in the dermis,and superficial subcutaneous tissues was formed by combining the multi-medium thermal diffusion model and the bio-thermal model(Pennes equation).The skins of the hand back of six healthy subjects were *** was found that the results revealed no consistent changes in thermal conductivity were observed across genders and *** measured blood perfusion rates were within the range of human capillary *** was found that female subjects had a higher perfusion rate range(0.0058-0.0061 s^(-1))than male subjects(0.0032-0.0049 s^(-1)),which is consistent with invasive medical studies about the gender difference in blood flow rates and stimulated effects in relaxation situations.

关键词： thermal conductivity blood perfusion rate harmonic method Pennes equation

Model-based offline reinforcement learning framework for optimizing tunnel boring machine operation

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Underground Space 2024年第6期19卷 47-71页

作者： Yupeng Cao Wei Luo Yadong Xue Weiren lin feng Zhang Department of Urban Management Kyoto UniversityKyoto 615-8540Japan Department of Geotechnical Engineering College of Civil EngineeringTongji UniversityShanghai 200092China Key Laboratory of Geotechnical and Underground Engineering of Ministry of Education Tongji UniversityShanghai 200092China

Research on automation and intelligent operation of tunnel boring machine(TBM)is receiving more and more attention,benefiting from the increasing construction ***,most studies on TBM operations optimization were trained by the labels of human drivers’decisions,which were subjective and *** a result,the control parameters suggested by these models could hardly surpass the performance of a human driver,even the possibility of subjective incorrect *** that the geomechanical feedback to TBM under drivers’actions is objective,in this paper,a transformer-based model called the geological response for tunnel boring machine(GRTBM),is proposed to learn the relationship between operation-adjust and TBM monitoring ***,with the model-based offline reinforcement learning,this paper provided a novel approach to optimizing the TBM excavation *** decision processes,recorded in the Yin-song TBM project for a waterway tunnel in Jilin Province of China,were used for the validation of the *** adopting an implicit perception of geological conditions in the GRTBM model,the suggested method achieved the desired state within a single action,greatly outperformed the practical adjustments where 500 s were taken,revealing the fact that the proposed model has the potential to surpass the capability of human beings.

关键词： TBM Reinforcement learning Transformer Data mining

Recent progress on the synthesis of defective UiO-66 for thermal catalysis

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Nano Research 2024年第10期17卷 8653-8670页

作者： Qing feng Caoyu Yang lin Chang Guodong Li Zhiyong Tang CAS Key Laboratory of Nanosystem and Hierarchical Fabrication CAS Center for Excellence in NanoscienceNational Center for Nanoscience and TechnologyBeijing 100190China School of Nanoscience and Engineering University of Chinese Academy of SciencesBeijing 100049China

Zirconium terephthalate UiO-66 has aroused great interest in catalysis since it exhibits significant flexibility and compatibility for accommodating a high number of defects as well as exceptional thermal and chemical *** now,many works have focused on the modulations of the Zr6-oxo clusters in UiO-66 in terms of diverse synthesis,advanced characterizations,and their catalytic *** achieve high catalytic efficiency,it is still highly desired for rationally constructing and modulating the Zr6-oxo clusters with exposed catalytic sites and diverse microenvironments for advanced *** this review,we provide a comprehensive summary of recent progress on the synthesis of defective UiO-66,qualitative and quantitative characterizations,as well as a logical overview of heterogeneous catalytic applications over the past few ***,the outlooks for the research paradigm of defective UiO-66 are discussed.

关键词： defective UiO-66 de novo synthesis post-synthetic treatment characterization thermal catalysis

Triclosan-conjugated,Lipase-responsive Polymeric Micelles for Eradication of Staphylococcal Biofilms

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Chinese Journal of Polymer Science 2024年第6期42卷 718-728页

作者： Yan-Qiang Huang Yuan-feng Li Yong Liu lin-Qi Shi Guangxi Technology Innovation Cooperation Base of Prevention and Control Pathogenic Microbes with Drug Resistance Youjiang Medical University for NationalitiesBaise533000China Translational Medicine Laboratory the First Affiliated Hospital of Wenzhou Medical UniversityWenzhou325035China Wenzhou Institute University of Chinese Academy of SciencesWenzhou325001China State Key Laboratory of Medicinal Chemical Biology Key Laboratory of Functional Polymer Materials of Ministry of Educationand Institute of Polymer ChemistryCollege of ChemistryNankai UniversityTianjin300071China

Bacterial biofilms present a significant challenge in treating drug-resistant infections,necessitating the development of innovative *** this study,we introduce triclosan-conjugated,lipase-responsive polymeric micelles designed to exploit biofilm properties and serve as a responsive drug delivery *** micelles were created using an amphiphilic block polymer synthesized via ring-opening polymerization ofε-caprolactone(CL)and triclosan-containing cyclic trimethylene carbonate(MTC-Tri).Poly(ethylene glycol)(PEG-OH)acted as the macro-initiator,resulting in micelles with a PEG shell that facilitated their penetration into bacterial *** important advantage of our micelles lies in their interaction with local bacterial lipases within *** lipases triggered rapid micelle degradation,releasing triclosan in a controlled *** liberated triclosan effectively eliminated bacteria embedded in the ***,the triclosan-conjugated micelles displayed minimal toxicity to murine fibroblasts,indicating their biocompatibility and *** finding emphasizes the potential application of these micelles in combatting drug resistance observed in bacterial *** triclosan-conjugated,lipase-responsive polymeric micelles exhibit promising characteristics for addressing drug resistance in bacterial *** harnessing biofilm properties and implementing a responsive drug delivery system,we seek to provide an effective solution in the fight against drug-resistant bacteria.

关键词： Self-assembly Polymer prodrug Ring-opening polymerization Biofilm eradication Cytotoxicity

Cr-catalyzed allylic C(sp^(3))–H addition to aldehydes enabled by photoinduced ligand-to-metal charge transfer

在线全文

学校读者我要写书评

暂无评论

Science China Chemistry 2024年第5期67卷 1589-1595页

作者： Xianrong Zeng feng-Hua Zhang Runchen Lai Xiaoyu lin Zhaobin Wang Key Laboratory of Precise Synthesis of Functional Molecules of Zhejiang Province Department of ChemistrySchool of Science and Research Center for Industries of the FutureWestlake UniversityHangzhou 310030China Institute of Natural Sciences Westlake Institute for Advanced StudyHangzhou 310024China Key Laboratory of Precise Synthesis of Functional Molecules of Zhejiang Province Instrumentation and Service Center for Molecular SciencesWestlake UniversityHangzhou 310024China

Photoinduced ligand-to-metal charge transfer(LMCT) has emerged as an effective strategy for synthesizing organic molecules in a sustainable manner. However, the majority of existing reports on selective C(sp^(3))–H bond functionalization via photoinduced LMCT focus on the use of late transition metals or rare-earth metals for radical additions or cross-couplings. In contrast, the utilization of photoinduced LMCT with 3d early transition metals poses a significant challenge. Herein, we describe an unprecedented approach to allylic C(sp^(3))–H addition to aldehydes, employing chromium(Cr) complexes as catalysts through visible-light-induced LMCT. By investigating the reaction pathway through various mechanistic studies, including radical trapping, kinetic isotope effect(KIE) analysis, and transient absorption spectroscopy, valuable insights have been gained. The proposed mechanism suggests the intermediacy of bromine radicals through homolysis of the Cr–Br bond. Notably, this protocol expands our understanding of the photochemical properties of earth-abundant Cr complexes.

关键词： Cr catalysis photoinduced ligand-to-metal charge transfer hydrogen-atom transfer carbonyl addition

Development of high-power microwave mechanical integrated continuous mining device

在线全文

学校读者我要写书评

暂无评论

Journal of Rock Mechanics and Geotechnical Engineering 2024年第9期16卷 3365-3377页

作者： Xia-Ting feng feng lin Jiuyu Zhang Chengxiang Yang Yuntan Ao Tianyang Tong Key Laboratory of Ministry of Education on Safe Mining of Deep Metal Mines Northeastern UniversityShenyang110819China Key Laboratory of Liaoning Province on Deep Engineering and Intelligent Technology Northeastern UniversityShenyang110819China

This article introduces a high-power microwave mechanical integrated continuous mining device,which can achieve synchronous cutting of hard rocks by microwave and *** device includes a cutting system,a rotary translation system,a loading system,a high-power microwave system,and a control and monitoring *** technology of“master-slave follow-up”disc cutter alternating side cutting of rock was proposed,which could improve the effectiveness of rock *** integrated structure of a microwave-cut system was then proposed,and synchronous motion of the microwave-cut system and adjustment of the loading system could be *** automatic adjustment technology of the microwave working distance was developed to dynamically control the optimal microwave working *** basic functions of the equipment were verified by *** comparing the two types of disk cutters,it is found that the master-slave follow-up disk cutter can improve significantly the dust removal effect and rock breaking efficiency in rock breaking process versus the conventional large disc *** tests of slate with or without microwave were conducted using a master-slave follow-up disk *** results show that the cutting patterns of slates change from intermittent chunks(without microwave irradiation)to persistent debris(with microwave irradiation),and the cutting speed is significantly improved(170%).The development of the device provides a scientific basis for changing the conventional mining technology of metal mines and realizing the mechanical continuous mining in hard metal mines.

关键词： Hard metal mine Microwave machinery Continuous mining Master-slave follow-up disc cutter

Microstructure and Mechanical Behavior of Mg-Based Bimetal Plates with High Formability Sleeve by Co-extrusion

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Acta Metallurgica Sinica(English Letters) 2024年第3期37卷 499-512页

作者： Yue-Hui Dang Sheng-lin Liu Xiao-Lei Ai Xiao-Wei feng Bo feng Zhuo Tian Ying-Fei lin Huan-Tao Chen Kai-Hong Zheng School of Materials Science and Engineering Chang’an UniversityShaanxi 710064China Guangdong Key Laboratory of Metal Toughening Technology and Application Institute of New MaterialsGuangdong Academy of SciencesGuangzhou 510650China

In this study,microstructure and mechanical behavior of two types of Mg-based bimetal plates with a high formability sleeve were systematically studied,with a great emphasis on the effect of the interface characteristic and the sleeve fraction on the plasticity of composite *** rule of mixtures(ROM)for elongation was also *** results show that when there is no or thin diffusion layer with thickness of about 3μm,Mg-based bimetal plates have a good plasticity with elongation of about 19-24%,and the ROM predicted elongations are very close to the experimental *** contrast,with a diffusion layer about 95-155μm thick,Mg-based bimetal plates exhibit a poor plasticity with elongation of about 11-17%,and the experimental elongations largely deviate from the ROM *** plasticity of Mg-based bimetal plates increases with increasing sleeve *** study provides new insights on the plastic deformation of Mg-based bimetal composites with a high formability sleeve.

关键词： Mg-based composites Co-extrusion Microstructure Mechanical behavior Plastic deformation