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Microstructures and magnetic properties of Sm(Co_(bal)Fe_(0.245)Cu_(0.07)Zr_(0.02))_(7.8)sintered magnet solution-treated at high temperature

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Rare Metals 2022年第12期41卷 4230-4234页

作者： Wei Sun Ming-Gang zhu Yi-Kun fang Zhao-hui Guo Wei Li Functional Materials Research Institute Central Iron and Steel Research InstituteBejing 100081China Beijing Engineering Laboratory of Advanced Metallic Magnetic Materials and Preparation Techniques Beijing 100081China

Sm(CoFeCuZr)zsintered permanent magnet has been attracting a great deal of attention by virtue of its high-temperature magnetic properties,low temperature coefficient and good corrosion and oxidation *** microstructures and magnetic properties of Sm(Co_(ba1)Fe_(0.245)Cu_(0.07)Zr_(0.02))_(7.8)sintered permanent magnet prepared by a traditional powder metallurgy method were *** magnetic properties,especially the maximum magnetic energy product,(BH)max,were obtained through adjusting solution-treated *** solution-treated temperature increasing from 1155 to 1195℃,remanence(Br)almost keeps constant and knee point coercivity(Hk),magnetic induction coercivity(H_(cb))and(B_(H))maxfirst increase and then *** intrinsic coercivity(H_(cj))of magnet solution-treated at 1195℃is 738 kA·m^(-1),which is less than 2/5 that of magnet solution-treated at 1183℃(>1927 kA·m^(-1)).The reason that magnet solution-treated at 1195℃shows lower Hcjthan magnet solution-treated at 1183℃is considered to be mainly related to the fact that there are a lot of cells with abnormally small *** addition,the lattice constant of Sm(Co_(bal)Fe_(0.245)Cu_(0.07)Zr_(0.02))_(7.8)sintered permanent magnet solution-treated at 1195℃,given by indexing highresolution transition electron microscope(HRTEM)results,is considered to be related to the formation of cells with abnormally small size which decreases H_(cj).

关键词： Microstructures Magnetic properties Sm(CoFeCuZr)_(z)sintered magnet High solution-treated temperature

A Projection Approach to Monotonic Regression with Bernstein Polynomials

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Journal of Systems Science & Complexity 2022年第5期35卷 1910-1928页

作者： zhu Guo fang Xiangzhong School of Mathematical Sciences Peking UniversityBeijing 100871China

Monotonic regression problems have been widely seen in many fields like economics and *** the monotonic parameter space is used by the Bayesian methods using Bernstein *** this paper the authors extend the usual parameter space to a larger space in which all the proper parameters making the regression function to be monotonic are *** order to ensure that the problem could be solved in the new parameter space,the authors use a projection posterior method to make *** authors show the proposed method has good approximation properties and performs well compared with other competing methods both in simulations and in practical applications.

关键词： Bayesian nonparametics monotonic regression posterior projection

人参皂苷 Rg3激活线粒体功能改善慢性疼痛的机制

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中国药理学通报 2025年第1期41卷 94-100页

作者：张培根朱海丽高卉湖北科技学院医学部药学院湖北咸宁437100

目的探究人参皂苷Rg3在慢性神经性疼痛中的作用及机制。方法筛选并分析慢性神经性疼痛数据中前额叶皮层内差异性表达基因;小鼠随机分为假手术组、模型组及给药组;采用坐骨神经慢性压迫损伤模型构建神经病理性疼痛动物模型,腹腔注射人参... 详细信息

目的探究人参皂苷Rg3在慢性神经性疼痛中的作用及机制。方法筛选并分析慢性神经性疼痛数据中前额叶皮层内差异性表达基因;小鼠随机分为假手术组、模型组及给药组;采用坐骨神经慢性压迫损伤模型构建神经病理性疼痛动物模型,腹腔注射人参皂苷Rg3给药;记录小鼠痛觉行为变化;HE染色、尼氏染色、免疫印迹及免疫组化检测各组PFC脑组织神经和线粒体损伤情况;分子对接探究人参皂苷Rg3的作用靶点;Mito-Tracker检测线粒体膜电位;ATP试剂盒分析ATP含量。结果与假手术组相比,模型组小鼠表现为痛觉过敏和运动能力受损;PFC内神经及线粒体损伤(P<0.05)。与模型组相比,人参皂苷Rg3给药可增加小鼠机械痛阈值、热缩足潜伏期和转棒停留时间;同时降低PFC内炎性细胞、尼氏小体及Dnm1l阳性细胞数,下调c-Fos、IL-1β和Dnm1l蛋白表达水平(P<0.05)。分子对接显示人参皂苷Rg3可结合Dnm1l。在细胞水平,人参皂苷Rg3给药可升高线粒体膜电位和ATP含量(P<0.05)。结论人参皂苷Rg3可通过调控降低PFC内炎症因子和线粒相关蛋白表达,改善线粒体功能,缓解CCI小鼠痛觉过敏。

关键词：人参皂苷Rg3 慢性神经性疼痛线粒体前额叶皮层 CCI PFC

Fcc/hcp PtNi heterostructured alloy nanocrystals with ultrathin Pt shell for enhanced catalytic performance towards hydrogen evolution reaction

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Nano Research 2024年第11期17卷 9822-9829页

作者： Tianchun Cheng Zhi Wang Shuiyang fang hui Jin Chongzhi zhu Shuangyang Zhao Guilin zhuang Qiaoli Chen Yihan zhu College of Chemical Engineering and State Key Laboratory Breeding Base of Green Chemical Synthesis Technology Zhejiang University of Technology Hangzhou 310014 China

To ensure the green and sustainable advancement of hydrogen energy, there is a critical need for the development of a cost-effective catalyst to address the sluggish kinetics of water electrolysis under alkaline conditions. An approach to achieve this is by constructing ultrathin Pt shell-structured catalysts that offer enhanced electrocatalytic hydrogen evolution reaction performance through modulation of the inner core while minimizing costs. Herein, an ultrathin Pt shell catalyst with an inner core consisting of a PtNi face-centered cubic and hexagonal-close-packed mixed-phase interface (named PtNi-mix) is synthesized through a pre-synthesis method followed by post-acid etching process. Encouragingly, the PtNi-mix catalyst only requires 12.9 mV overpotential to achieve a current density of 10 mA·cm^(-2) in 1 M KOH, which is much lower than that of the commercial 20 wt.% Pt/C catalyst (71.2 mV). Also, it possesses a high mass activity (7.2 A·mg^(-1)) at an overpotential of 70 mV, which is 9 times higher than that of the commercial 20 wt.% Pt/C catalyst. Additionally, the performance of the PtNi-mix catalyst remains almost unchanged after 10,000 cyclic voltammetry tests, indicating that the catalyst exhibits excellent stability.

关键词： noble metal crystal phase electrocatalysis hydrogen evolution reaction

Seepage safety monitoring model for an earth rock dam under influence of high-impact typhoons based on particle swarm optimization algorithm

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Water Science and Engineering 2017年第1期10卷 70-77页

作者： Yan Xiang Shu-yan Fu Kai zhu hui Yuan Zhi-yuan fang Dam Safety Management Center of the Ministry of Water Resources Nanjing Hydraulic Research InstituteNanjing 210029China State Key Laboratory of Hydrology-Water Resources and Hydraulic Engineering Nanjing Hydraulic Research InstituteNanjing 210029China College of Mechanics and Materials Hohai UniversityNanjing 210098China School of Water Resources and Hydraulic Engineering Yunnan Agricultural UniversityKunming 650000China

Extreme hydrological events induced by typhoons in reservoir areas have presented severe challenges to the safe operation of hydraulic structures. Based on analysis of the seepage characteristics of an earth rock dam, a novel seepage safety monitoring model was constructed in this study. The nonlinear influence processes of the antecedent reservoir water level and rainfall were assumed to follow normal distributions. The particle swarm optimization （PSO） algorithm was used to optimize the model parameters so as to raise the fitting accuracy. In addition, a mutation factor was introduced to simulate the sudden increase in the piezometric level induced by short-duration heavy rainfall and the possible historical extreme reservoir water level during a typhoon. In order to verify the efficacy of this model, the earth rock dam of the Siminghu Reservoir was used as an example. The piezometric level at the SW1-2 measuring point during Typhoon Fitow in 2013 was fitted with the present model, and a corresponding theoretical expression was established. Comparison of fitting results of the piezometric level obtained from the present statistical model and traditional statistical model with monitored values during the typhoon shows that the present model has a higher fitting accuracy and can simulate the uprush feature of the seepage pressure during the typhoon perfectly.

关键词： Monitoring model Particle swarm optimization algorithm Earth rock dam Lagging effect Typhoon Seepage pressure Mutation factor Piezometric level

Vault predicting after implantable collamer lens implantation using random forest network based on different features in ultrasound biomicroscopy images

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International Journal of Ophthalmology(English edition) 2023年第10期16卷 1561-1567页

作者： Bin fang Qiu-Jian zhu hui Yang Li-Cheng Fan School of Mechanical and Electrical Engineering Soochow UniversitySuzhou 215100Jiangsu ProvinceChina Lixiang Eye Hospital of Soochow University Suzhou 215021 Jiangsu ProvinceChina

AIM:To analyze ultrasound biomicroscopy(UBM)images using random forest network to find new features to make predictions about vault after implantable collamer lens(ICL)***:A total of 450 UBM images were collected from the Lixiang Eye Hospital to provide the patient’s preoperative parameters as well as the vault of the ICL after *** vault was set as the prediction target,and the input elements were mainly ciliary sulcus shape parameters,which included 6 angular parameters,2 area parameters,and 2 parameters,distance between ciliary sulci,and anterior chamber height.A random forest regression model was applied to predict the vault,with the number of base estimators(n_estimators)of 2000,the maximum tree depth(max_depth)of 17,the number of tree features(max_features)of Auto,and the random state(random_state)of ***:Among the parameters selected in this study,the distance between ciliary sulci had a greater importance proportion,reaching 52%before parameter optimization is performed,and other features had less influence,with an importance proportion of about 5%.The importance of the distance between the ciliary sulci increased to 53% after parameter optimization,and the importance of angle 3 and area 1 increased to 5% and 8%respectively,while the importance of the other parameters remained unchanged,and the distance between the ciliary sulci was considered the most important *** features,although they accounted for a relatively small proportion,also had an impact on the vault *** parameter optimization,the best prediction results were obtained,with a predicted mean value of 763.688μm and an actual mean value of 776.9304μ*** R²was 0.4456 and the root mean square error was ***:A study based on UBM images using random forest network can be performed for prediction of the vault after ICL implantation and can provide some reference for ICL size selection.

关键词： random forest network ultrasound biomicroscopy images vault prediction implantable collamer lens

Design and Analysis of a Novel Hybrid Processing Robot Mechanism

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International Journal of Automation and computing 2020年第3期17卷 403-416页

作者： Hai-Rong fang Tong zhu Hai-Qiang Zhang hui Yang Bing-Shan Jiang School of Mechanical Electronic and Control EngineeringBeijing Jiaotong UniversityBeijing 100044China

In order to satisfy the requirements of large workspace and high dexterity for processing equipment of oversized cylindrical boxes′spherical crown surfaces in the aerospace industry,a novel serial-parallel hybrid processing robot mechanism is *** degrees of freedom of the 5PUS-(2UR)PU parallel mechanism are obtained by using the screw *** inverse kinematics of the hybrid mechanism are analyzed and the velocity Jacobian matrix is ***,the constraints of the main factors influencing workspace of the mechanism are given,and the position and posture workspace are ***,the dexterity and stiffness performance of the mechanism is analyzed based on the Jacobian *** virtual prototype is established,and the theoretical calculation and simulation analysis of the hybrid mechanism with arc curve as the processing trajectory are carried out by using Matlab and Adams *** research results show that the mechanism can satisfy the requirements of large workspace and high dexterity of oversized cylindrical boxes′spherical crown surface processing,and has feasibility and practical application value.

关键词： Hybrid mechanism kinematic analysis large workspace dexterity kinematic simulation

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蓝碳交易认证及运行机制的挑战与应对

北京科技大学学报（社会科学版） 2025年第1期41卷 61-68页

作者：朱晖赵佳齐大连海洋大学海洋法律与人文学院大连116023

重启全国温室气体自愿减排交易市场是蓝碳纳入自愿碳市场的重要契机,但蓝碳交易制度体系仍处在初步发展阶段,缺乏完善的配套措施。我国蓝碳交易制度仍然存在交易规则功能缺失、定价机制失范、交易方式欠缺和核查监管机制不足等问题。为... 详细信息

重启全国温室气体自愿减排交易市场是蓝碳纳入自愿碳市场的重要契机,但蓝碳交易制度体系仍处在初步发展阶段,缺乏完善的配套措施。我国蓝碳交易制度仍然存在交易规则功能缺失、定价机制失范、交易方式欠缺和核查监管机制不足等问题。为保证蓝碳交易在法律规制下运行,构建公开、透明、可预期的蓝碳交易机制,应实现蓝碳交易的功能完善、规范定价机制,同时推动交易方式多元发展、健全核查机构监管机制以优化蓝碳交易运行机制,从而搭建蓝碳交易纳入自愿碳市场的规则体系。

关键词：蓝碳 CCER 交易规则定价机制监管机制

Stereodivergently asymmetric synthesis of chiral phosphorus compounds by synergistic combination of ion-pair catalyst and base

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Science China Chemistry 2022年第12期65卷 2500-2511页

作者： hui-Lin Hu Xiaoyu Ren Jiajia He Lixiang zhu Siqiang fang Zhishan Su Tianli Wang Key Laboratory of Green Chemistry&Technology Ministry of EducationCollege of ChemistrySichuan UniversityChengdu610064China

Stereodivergently constructing the designed products having adjacent multi-stereocenters via a given reaction,with excellent control of both absolute and relative configurations,presents one of the substantial hurdles in asymmetric ***,we report a precisely stereodivergent asymmetric protocol by synergistic combination of phosphonium-involved ion-pair catalysis and base for accessing to chiral phosphorus compounds bearing two adjacent chiral centers particularly containing an acidic protonated enantioenriched carbon atom,having broad functional group compatibility in both dynamic and thermodynamic processes under mild reaction *** keys for the success in constructing these stereoisomers with high levels of regio-,diastereo-,and enantioselectivities were contained:firstly,the precise stereo-control in providing dynamic products was enabled by bifunctional phosphonium salt catalyst with semi-enclosed cavity;secondly,the readily stereospecific transformation of adducts from dynamic to thermodynamic version was initiated by achiral *** four stereoisomers could be readily accessed even in gram-scale in high yields with maintaining excellent stereoselectivities,illustrating the potential of this synergistic catalytic methodology in organic ***,mechanistic studies including density functional theory(DFT)calculations and control experiments provide insights into the mechanism.

关键词： stereodivergent asymmetric synthesis chiral phosphorus compounds dipeptided phosphonium salts cooperative catalysis base control