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Journal of Iron and Steel Research International 2020年第12期27卷 1363-1371页

作者： Fo-quan Gu yuan-bo zhang Guang-hui Li Qiang Zhong Jun Luo Zi-jian Su Ming-jun Rao Zhi-wei Peng Tao Jiang School of Minerals Processing and Bioengineering Central South UniversityChangsha 410083HunanChina

Effect of distribution of iron concentrates between pelletized and matrix feed on the preparation of blast furnace burdens from two different kinds of fine iron concentrates (magnetite and hematite) by composite agglomeration process (CAP) was explored. It was found that when the mass ratio of iron concentrate A (magnetite) to iron concentrate B (hematite) in the mixed feed was constant, the proportion of iron concentrate A in the pelletized and matrix feed significantly affected the quality of CAP products. Particularly, as the proportion of iron concentrate A in the pelletized feed increased from 0 to 100%, the yield decreased from 82.11% to 79.19% and the tumbler index decreased from 71.33% to 68.27%. The mineralization characterization results indicated that when 100% iron concentrate A was used as the pelletized feed, the crystallization styles of the outer layer and the inner layer of the pellet were different, and a lot of pores exist around hematite and magnetite phases in the pelletized part, with the weak connection of pelletized and matrix part, resulting in poor strength of agglomeration product.

关键词： Composite agglomeration process Sintering Fine iron concentrate Pelletized feed Blast furnace burden

Retrieval-and-alignment based large-scale indoor point cloud semantic segmentation

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Science China(Information Sciences) 2024年第4期67卷 164-180页

作者： Zongyi XU Xiaoshui HUANG bo yuan Yangfu WANG Qianni zhang Weisheng LI Xinbo GAO School of Computer Science and Technology Chongqing University of Posts and Telecommunications Shanghai Artificial Intelligence Laboratory School of Electronic Engineering and Computer Science Queen Mary University of London

Current methods for point cloud semantic segmentation depend on the extraction of descriptive features. However, unlike images, point clouds are irregular and often lack texture information, making it demanding to extract discriminative features. In addition, noise, outliers, and uneven point distribution are commonly present in point clouds, which further complicates the segmentation task. To address these problems, a novel architecture is proposed for direct and accurate large-scale point cloud segmentation based on point cloud retrieval and alignment. The proposed approach involves using a feature-based point cloud retrieval method for searching for reference point clouds with annotations from a dataset. In the following segmentation stage, an overlap-based point cloud registration method has been developed to align the target and reference point clouds. For accurate and robust alignment, an overlap region estimation module is trained to locate the optimal overlap region between two pieces of point clouds in a coarse-to-fine manner. In the detected overlap region, the global and local features of the points are extracted and combined for featuremetric registration to obtain accurate transformation parameters between the target and reference point clouds. After alignment, the annotated segmentation of the reference is transferred to the target point clouds to obtain accurate segmentation results. Extensive experiments are conducted to show that the developed method outperforms the state-of-the-art approaches in terms of both accuracy and robustness against noise and outliers.

关键词： point cloud semantic segmentation large-scale indoor point clouds point cloud alignment overlap estimation label transfer

Application of pulse index continuous cardiac output system in elderly patients with acute myocardial infarction complicated by cardiogenic shock: A prospective randomized study

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World Journal of Clinical Cases 2019年第11期7卷 1291-1301页

作者： yuan-bo zhang Zhi-Zhong zhang Jun-Xia Li Yu-Hong Wang Wei-Lin zhang Xin-Li Tian Yun-Feng Han Meng Yang Yu Liu Department of Cardiovascular Medicine The Seventh Medical Center General Hospital of the Chinese PLA Beijing 100700 China Department of Emergency Medicine Beijing Friendship Hospital Capital Medical University Beijing 100050 China Department of Emergency Medicine The Seventh Medical Center General Hospital of Chinese PLA Beijing 100700 China Institute of Zoology Chinese Academy of Sciences Beijing 100101 China Department of Emergency Medicine Dongzhimen Hospital The First Affiliated Hospital of Beijing University of Chinese Medicine Beijing 100700 China

BACKGROUND Cardiogenic shock (CS) secondary to acute myocardial infarction (AMI) complicates management of the condition, and often leads to poor prognosis. Prompt and accurate monitoring of cardiovascular and accompanying hemodynamic changes is crucial in achieving adequate management of the condition. Advances in technology has availed procedures such as pulse index continuous cardiac output (PiCCO), which can offer precise monitoring of cardiovascular functions and hemodynamic parameters. In this study, PiCCO is evaluated for its potential utility in improving management and clinical outcomes among elderly patients with AMI complicated by CS. AIM To assess whether use of the PiCCO system can improve clinical outcomes in elderly patients with AMI complicated by *** Patients from emergency intensive care units (EICU) or coronary care units (CCU) were randomized to receive PiCCO monitoring or not. The APACHE II score, SOFA score, hs-TnI, NT-proBNP, PaO2/FiO2 ratio and lactate levels on day 1, 3 and 7 after treatment were compared. The infusion and urine volume at 0-24 h, 24-48 h and 48-72 h were recorded, as were the cardiac index (CI), extravascular lung water index (EVLWI), intrathoracic blood volume index (ITBVI) and global end diastolic volume index (GEDVI) at similar time intervals. RESULTS Sixty patients with AMI complicated by CS were included in the study. The PiCCO group had a significantly lower APACHE II score, SOFA score, hs-TnI and NT-proBNP levels on day 1, 3 and 7 after treatment. The infusion and urine volume during 0-24 h in the PiCCO group were significantly greater, and this group also showed significantly higher ADL scores. Furthermore, the PiCCO group spent lesser days on vasoactive agents, mechanical ventilation, and had a reduced length of stay in EICU/CCU. Additionally, the CI was significantly higher at 48 h and 72 h in the PiCCO group compared with that at 24 h, and the EVLWI, ITBVI and GEDVI were significantly decreased at 48 h and

关键词： Pulse index continuous cardiac output Elderly patients Cardiogenic shock Acute myocardial infarction

Complexes of cupric ion and tartaric acid enhanced calcium peroxide Fenton-like reaction for metronidazole degradation

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Chinese Chemical Letters 2024年第7期35卷 183-187页

作者： Shiyu Pan bo Cao Deling yuan Tifeng Jiao Qingrui zhang Shoufeng Tang State Key Laboratory of Metastable Materials Science and Technology Hebei Key Laboratory of Heavy Metal Deep-Remediation in Water and Resource ReuseSchool of Environmental and Chemical EngineeringYanshan UniversityQinhuangdao 066004China

To surmount the obstacles of traditional Fenton method and synchronously utilize Cu^(2+)and polyphenol in water,an improved Fenton-like reaction applying calcium peroxide(CaO_(2))as H_(2)O_(2)source and regulating by the complex of Cu^(2+)-tartaric acid(TA,a representative of polyphenol)was constructed.A typical antibiotic,metronidazole(MTZ)could be effectively eliminated by the Cu^(2+)/TA/CaO_(2)system,and the optimized parameters were as follows:0.1 mmol/L Cu^(2+),2 mmol/L TA,2 mmol/L CaO_(2),and initial *** spectrum confirmed the formation of Cu^(2+)-TA complex,which promoted the Cu^(2+)/Cu+circulation through decreasing the Cu^(2+)/Cu^(+) couple redox potential,which further enhanced the H_(2)O_(2)decomposition and the formation of reactive *** radical was dominant for MTZ degradation,followed by oxygen and superoxide *** degradation intermediates of MTZ were detected and their evolution way was ***,the ternary process showed a wide p H tolerance(3–8)for removing MTZ and broad applicability for eliminating other dyes and *** work provided a reference for Cu-based Fenton-like strategy for organic wastewater settlement.

关键词： Cupric ion Tartaric acid Complexation Calcium peroxide Metronidazole removal

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Development of a high-repetition-rate lumped-inductance kicker magnet prototype for the beam switchyard of SHINE

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Nuclear Science and Techniques 2024年第2期35卷 20-31页

作者： Yong-Fang Liu Rui-Ping Wang Jin Tong bo zhang Si Chen Qi-Bing yuan Hai-Xiao Deng Ming Gu bo Liu Shanghai Advanced Research Institute Chinese Academy of SciencesShanghai 201412People’s Republic of China

The Shanghai high-repetition-rate X-ray free-electron laser and extreme light facility(SHINE)operates at a maximum repetition rate of 1 *** magnets are key components that distribute electron bunches into three different undulator lines in a bunch-by-bunch *** kicker field width must be less than the time interval between bunches.A lumpedinductance kicker prototype was developed using a vacuum chamber with a single-turn *** full magnetic field strength was 0.005 *** paper presents the requirements,design considerations,design parameters,magnetic field calculations,and measurements of the kicker *** relevant experimental results are also *** pulse width of the magnetic field was approximately 600 ns,and the maximum operation repetition rate was 1 *** developed kicker satisfies the requirements for the SHINE ***,numerous recommendations for the future optimization of kicker magnets are provided.

关键词： X-ray free-electron laser Kicker magnet Beam switchyard High repetition rate Ni-Zn ferrites

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A lethal mice model of recombinant vesicular stomatitis viruses for EboV-targeting prophylactic vaccines evaluation

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Virologica Sinica 2024年第3期39卷 516-519页

作者： Hong-Qing zhang Zhe-Rui zhang Cheng-Lin Deng Zhi-Ming yuan bo zhang Key Laboratory of Special Pathogens and Biosafety Wuhan Institute of VirologyCenter for Biosafety Mega-ScienceChinese Academy of SciencesWuhan430071China University of Chinese Academy of Sciences Beijing100049China Hubei Jiangxia Laboratory Wuhan430200China

Dear editor,Ebola virus(EboV)is a member of the genus Orthoebolavirus within the family of ***'s the causative agent of Ebola virus disease(EVD),characterized by general malaise,severe gastrointestinal illness,febrile,coagulopathy,multi-organs dysfunction,and high mortality(up to 90%)in humans and nonhuman primates(NHPs)(Jacob et al.,2020).Since its discovery in 1976,EboV has grabbed the global concerns,especially after the West African epidemic from 2014 to 2016,which resulted in 30,000 cases and over 11,000 deaths(Feldmann et al.,2020;Jacob et al.,2020).From 2018 to 2022,there have been thousands of infections primarily in the Democratic Republic of the Congo(DRC),resulting in over 2000 *** highlights the importance of continued attention and ongoing surveillance(***/emergenci es/disease-outbreak-news).

关键词： organs mortality editor

A variable structure passivity control method for elastic joint robots based on cascaded high-order state estimation

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Science China(Technological Sciences) 2024年第2期67卷 395-407页

作者： zhang JieXin NIE PingYun zhang bo State Key Laboratory of Mechanical System and Vibration School of Mechanical EngineeringShanghai Jiao Tong UniversityShanghai200240China

Passivity-based controllers are widely used to facilitate physical interaction between humans and elastic joint robots,as they enhance the stability of the interaction ***,the joint position tracking performance can be limited by the structures of these controllers when the system is faced with uncertainties and rough high-order system state measurements(such as joint accelerations and jerks).This study presents a variable structure passivity(VSP)control method for joint position tracking of elastic joint robots,which combines the advantages of passive control and variable structure *** method ensures the tracking error converges in a finite time,even when the system faces *** method also preserves the passivity of the ***,a cascaded observer,called CHOSSO,is also proposed to accurately estimate high-order system states,relying only on position and velocity *** observer allows independent implementation of disturbance compensation in the acceleration and jerk estimation *** particular,the observer has an enhanced ability to handle fast time-varying disturbances in physical human-robot *** effectiveness of the proposed method is verified through simulations and experiments on a lower limb rehabilitation robot equipped with elastic joints.

关键词： motion control elastic joint robot finite-time convergence high-order system state estimation physical human-robot interaction

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Automated regression test method for scientific computing libraries:Illustration with SPHinXsys

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Journal of Hydrodynamics 2024年第3期36卷 466-478页

作者： bo zhang Chi zhang Xiangyu Hu TUM School of Engineering and Design Technical University of MunichMunichGermany

Scientific computing libraries,whether in-house or open-source,have witnessed enormous progress in both engineering and scientific ***,it is important to ensure that modifications to the source code,prompted by bug fixing or new feature development,do not compromise the accuracy and functionality that have been already validated and *** paper introduces a method for establishing and implementing an automatic regression test environment,using the open-source multi-physics library SPHinXsys as an illustrative ***,a reference database for each benchmark test is generated from observed data across multiple *** comprehensive database encapsulates the maximum variation range of metrics for different strategies,including the time-averaged,ensemble-averaged,and dynamic time warping *** accounts for uncertainties arising from parallel computing,particle relaxation,physical instabilities,and ***,new results obtained after source code modifications undergo testing based on a curve-similarity comparison against the reference *** the source code is updated,the regression test is automatically executed for all test cases,providing a comprehensive assessment of the validity of the current *** regression test environment has been successfully implemented in all dynamic test cases within SPHinXsys,including fluid dynamics,solid mechanics,fluid-structure interaction,thermal and mass diffusion,reaction-diffusion,and their multi-physics couplings,and demonstrates robust capabilities in testing different *** is noted that while the current test environment is built and implemented for a particular scientific computing library,its underlying principles are generic and can be easily adapted for use with other libraries,achieving equal effectiveness.

关键词： Scientific computing open-source library verification and validation regression test automatic test environment curve similarity comparison smoothed particle hydrodynamics

Oxygen reduction electrocatalysis:From conventional to single-atomic platinum-based catalysts for proton exchange membrane fuel cells

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Frontiers in Energy 2024年第2期18卷 206-222页

作者： Cheng yuan Shiming zhang Jiujun zhang Institute for Sustainable Energy/College of Sciences Shanghai UniversityShanghai 200444China

Platinum(Pt)-based materials are still the most efficient and practical catalysts to drive the sluggish kinetics of cathodic oxygen reduction reaction(ORR)in proton exchange membrane fuel cells(PEMFCs).However,their catalysis and stability performance still need to be further improved in terms of corrosion of both carbon support and Pt catalyst particles as well as Pt loading *** on the developed synthetic strategies of alloying/nanostructuring Pt particles and modifying/innovating supports in developing conventional Pt-based catalysts,Pt single-atom catalysts(Pt SACs)as the recently burgeoning hot materials with a potential to achieve the maximum utilization of Pt are comprehensively reviewed in this *** design thoughts and synthesis of various isolated,alloyed,and nanoparticlecontained Pt SACs are *** single-atomic Pt coordinating with non-metals and alloying with metals as well as the metal-support interactions of Pt single-atoms with carbon/non-carbon supports are emphasized in terms of the ORR activity and stability of the *** advance further research and development of Pt SACs for viable implementation in PEMFCs,various technical challenges and several potential research directions are outlined.

关键词： oxygen reduction electrocatalysis Pt singleatom catalysts conventional Pt-based catalysts design thoughts and synthesis metal-support interactions

Competitive assembling strategy to construct carbon nitride homojunctions for boosting photocatalytic performance

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Journal of Materials Science & Technology 2024年第5期172卷 23-32页

作者： Hua-Wei zhang yuan-yuan Li bo Li Jing-Hui Shi Tao Huang Gui-Fang Huang Anlian Pan Wangyu Hu Wei-Qing Huang School of Physics&Electronic Engineering Zhengzhou University of Light IndustryZhengzhou 450002China Key Laboratory for Micro/Nano Optoelectronic Devices of Ministry of Education&Hunan Provincial Key Laboratory of Low-Dimensional Structural Physics and Devices School of Physics and ElectronicsHunan UniversityChangsha 410082China College of Materials Science and Engineering Hunan UniversityChangsha 410082China

both morphology and composition have a great influence on the properties and functions of materials,however,how to rational modulate both of them to achieve their synergistic effects has been a longstanding ***,we demonstrate a competitive assembling strategy for the construction of metal-free graphite carbon nitride(CN)homojunctions in which morphology and composition can be easily controlled simultaneously by only changing the ratio of assembly raw *** homojunctions are comprised of porous nanotubular S-doped CN(SCN)grafted with CN nanovesicles,which are derived from thermal polycondensation of melamine-thiocyanuric acid(M-T)/melamine-cyanuric acid(M-C)supramolecular hybrid *** unique architecture and component engineering endows the novel SCN-CN homojunction with abundant active sites,enhanced visible trapping ability,and intimate interface *** a result,the synthesized SCN-CN homojunctions demonstrate high photocatalytic activity for hydrogen evolution and pollutant *** developed strategy opens up intriguing opportu-nities for the rational construction of intricate metal-free heterostructures with controllable architecture and interfacial contact for applications in energy-related fields.

关键词： Competitive assembling strategy Supramolecular hybrid blocks Homojunctions Graphite carbon nitride Photocatalytic