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Advances in Manufacturing 2019年第2期7卷 238-247页

作者： dong-dong chen Yong-cheng Lin Xiao-Min chen School of Mechanical and Electrical Engineering Central South University Changsha 410083 People's Republic of China State Key Laboratory of High Performance Complex Manufacturing Changsha 410083 People's Republic of China College of Automotive and Mechanical Engineering Changsha University of Science and Technology Changsha 410114 People's Republic of China

In this study, a strategy based on the particle swarm optimization (PSO) algorithm is developed to control the microstructures of a Ni-based superalloy during hot forging. This strategy is composed of three parts, namely, material models, optimality criterions, and a PSO algo rithm. The material models are utilized to predict microstructure information, such as recrystallization volume fraction and average grain size. The optimality crite? non can be determined by the designed target microstructures and random errors. The developed strategy is resolved using the PSO algorithm, which is an intelligent optimal algorithm. This algorithm does not need a derivable objective function, which renders it suitable for dealing with the complex hot forging process of alloy components. The optimal processing parameters (deformation temperature and strain rate) are obtained by the developed strategy and validated by the hot forging experiments. Uniform and fine target microstructures can be obtained using the optimized processing parameters, which indicates that the developed strategy is effective for controlling the microstructural evolution during the hot forging of the studied superalloy.

关键词： Processing parameters Microstructure Particle swarm optimization (PSO) algorithm Superalloy

Discrete multi-step phase hologram for high frequency acoustic modulation

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Chinese Physics B 2024年第1期33卷 488-495页

作者：周梦晴李照希李怡王业成张娟谌东东全熠杨银堂费春龙 School of Microelectronics Xidian UniversityXi'an 710071China

Acoustic holograms can recover wavefront stored acoustic field information and produce high-fidelity complex acoustic fields. Benefiting from the huge spatial information that traditional acoustic elements cannot match, acoustic holograms pursue the realization of high-resolution complex acoustic fields and gradually tend to high-frequency ultrasound applications. However, conventional continuous phase holograms are limited by three-dimensional(3D) printing size, and the presence of unavoidable small printing errors makes it difficult to achieve acoustic field reconstruction at high frequency accuracy. Here, we present an optimized discrete multi-step phase hologram. It can ensure the reconstruction quality of image with high robustness, and properly lower the requirement for the 3D printing accuracy. Meanwhile, the concept of reconstruction similarity is proposed to refine a measure of acoustic field quality. In addition, the realized complex acoustic field at 20 MHz promotes the application of acoustic holograms at high frequencies and provides a new way to generate high-fidelity acoustic fields.

关键词： discrete multi-step phase hologram econstruction quality 3D printing accuracy high-fidelity

Modeling sintering behavior of metal fibers with different fiber angles

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Rare Metals 2018年第10期37卷 886-893页

作者： dong-dong chen Zhou-Shun Zheng Jian-Zhong Wang Hui-Ping Tang School of Mathematics and Statistics Central South University State Key Laboratory of Porous Metal Materials Northwest Institute for Nonferrous Metal Research

The formation of sintering necks between two metal fibers was investigated using the oval-oval model with respect to the fiber angle range of 0°-90°. Surface diffusion was assumed to be the predominant mechanism in every section of the junction of two metal fibers in this model, which was addressed numerically using the level- set method. The growth rates of the sintering necks in the direction of the bisector of obtuse angle, the bisector of acute angle and the fiber axis were discussed in detail. It is found that the growth rate of the sintering necks decreases with fiber angle increasing in the direction of the fiber axis and the bisector of acute angle. However, an opposite variation in growth rate of sintering necks can be found in the direction of the bisector of obtuse angle. The numerical simulation results show that the growth rate of the sintering necks is significantly affected by the initial local geomet- rical structure which is determined by the fiber angle.

关键词： Metal fiber Surface diffusion Fiber angle Initial local geometrical structure Initial evolution speed

富马酸丙酚替诺福韦片在中国健康受试者体内的生物等效性研究

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中国临床药理学杂志 2024年第14期40卷 2113-2117页

作者：李晓斌汪楠胡妮娜王宁董晨东崔晓彤谢荷田妍王文萍辽宁中医药大学附属医院Ⅰ期临床病房辽宁沈阳110032 华润三九医药股份有限公司创新药物研究院广东深圳5181100 安徽万邦医药科技股份有限公司安徽合肥230088

目的评价富马酸丙酚替诺福韦片(25 mg)在中国健康受试者中的药代动力学(PK)行为,以及2种制剂的生物等效性。方法空腹试验采用单次给药、随机、开放、两周期、双交叉设计,餐后试验采用单次给药、随机、开放、三周期、部分重复交叉设计。... 详细信息

目的评价富马酸丙酚替诺福韦片(25 mg)在中国健康受试者中的药代动力学(PK)行为,以及2种制剂的生物等效性。方法空腹试验采用单次给药、随机、开放、两周期、双交叉设计,餐后试验采用单次给药、随机、开放、三周期、部分重复交叉设计。空腹和餐后试验各入组42例健康受试者,每周期单次口服富马酸丙酚替诺福韦片受试制剂和参比制剂各25 mg。用液相色谱-串联质谱(LC-MS/MS)法检测人血浆中丙酚替诺福韦和替诺福韦的浓度,用WinNonlin软件(8.1版本)以非房室模型计算PK参数,并评价2种制剂的生物等效性,并对试验期间受试者进行相关的安全性评价。结果空腹口服受试制剂和参比制剂后,酚替诺福韦的主要PK参数:Cmax分别为(215.17±94.24)和(199.30±71.11)ng·mL^(-1),AUC_(0-t)分别为(135.44±71.60)和(123.91±53.82)h·ng·mL^(-1);替诺福韦的主要PK参数:受试制剂和参比制剂的C_(max)分别为(7.30±2.27)和(7.12±1.74)ng·mL^(-1),AUC_(0-t)分别为(186.78±60.22)和(179.44±47.44)h·ng·mL^(-1)。餐后口服受试制剂和参比制剂后,丙酚替诺福韦主要药代动力学参数:C_(max)分别为(197.69±82.19)和(197.10±110.54)ng·mL^(-1),AUC_(0-t)分别为(197.69±82.19)和(197.10±110.54)h·ng·mL^(-1);替诺福韦主要PK参数:受试制剂和参比制剂的C_(max)分别为(2.57±1.37)和(2.58±1.31)ng·mL^(-1),AUC_(0-t)分别为(227.08±74.33)和(238.51±128.30)h·ng·mL^(-1)。空腹和餐后试验受试制剂和参比制剂的C_(max)、AUC_(0-t)的几何均值比的90%置信区间均在80.00%~125.00%。空腹和餐后试验的不良事件发生率分别为21.43%和30.95%,未发生严重不良事件。结论富马酸丙酚替诺福韦片受试制剂和参比制剂具有生物等效性,且安全性良好。

关键词：丙酚替诺福韦替诺福韦生物等效性安全性

Genetic Prion Disease:Insight from the Features and Experience of China National Surveillance for Creutzfeldt-Jakob Disease

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Neuroscience Bulletin 2021年第11期37卷 1570-1582页

作者： Qi Shi Cao chen Kang Xiao Wei Zhou Li-Ping Gao dong-dong chen Yue-Zhang Wu Yuan Wang Chao Hu chen Gao Xiao-Ping dong State Key Laboratory for Infectious Disease Prevention and Control Collaborative Innovation Center for Diagnosis and Treatment of Infectious Diseases(Zhejiang University)National Institute for Viral Disease Control and PreventionChinese Center for Disease Control and PreventionBeijing102206China Center for Global Public Health Chinese Center for Disease Control and PreventionBeijing102206China Center for Biosafety Mega-Science Chinese Academy of SciencesWuhan430064China China Academy of Chinese Medical Sciences Beijing100700China

Human genetic prion diseases(gPrDs)are directly associated with mutations and insertions in the PRNP(Prion Protein)*** collected and analyzed the data of 218 Chinese gPrD patients identified between Jan 2006 and June *** different subtypes were identified and gPrDs accounted for 10.9%of all diagnosed PrDs within the same *** subtypes of gPrDs showed a degree of geographic *** age at onset of Chinese gPrDs peaked in the 50–59 year ***–Sträussler–Scheinker syndrome(GSS)and fatal familial insomnia(FFI)cases usually displayed clinical symptoms earlier than genetic Creutzfeldt–Jakob disease(gCJD)patients with point mutations.A family history was more frequently recalled in P105L GSS and D178N FFI patients than T188K and E200K *** of the E196A gCJD patients reported a family *** gCJD cases with point mutations always developed clinical manifestations typical of sporadic CJD(sCJD).EEG examination was not sensitive for ***-associated abnormalities on MRI were found in high proportions of GSS and gCJD *** 14-3-3 positivity was frequently detected in gCJD *** CSF tau was found in more than half of FFI and T188K gCJD cases,and an even higher proportion of E196A and E200K gCJD patients.63.6%of P105L GSS cases showed a positive reaction in cerebrospinal fluid *** and FFI cases had longer durations than most subtypes of *** is one of the largest studies of gPrDs in East Asians,and the illness profile of Chinese gPrDs is clearly *** high proportions of T188K and E196A occur among Chinese gPrDs;these mutations are rarely reported in Caucasians and Japanese.

关键词： Genetic prion disease Mutation Surveillance Creutzfeldt-Jakob disease Gerstmann-Sträussler-Scheinker syndrome Fatal familial insomnia

Synergistic Impacts of Indian Ocean SST and Indo-China Peninsula Soil Moisture on the 2020 Record-breaking Mei-yu

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Advances in Atmospheric Sciences 2024年第9期41卷 1735-1750页

作者： Yinshuo dong Haishan chen Xuan dong Wenjian HUA Wenjun ZHANG Key Laboratory of Meteorological Disaster Ministry of Education/Joint International Research Laboratory of Climate and Environment Change/Collaborative Innovation Center on Forecast and Evaluation of Meteorological DisastersNanjing University of Information Science and TechnologyNanjing 210044China School of Atmospheric Sciences Nanjing University of Information Science and TechnologyNanjing 210044China Bureau of Hydrology ChangJiang Water Resources CommissionWuhan 430010China

The Yangtze River basin(YRB)experienced a record-breaking mei-yu season in June‒July *** unique long-lasting extreme event and its origin have attracted considerable *** studies have suggested that the Indian Ocean(IO)SST forcing and soil moisture anomaly over the Indochina Peninsula(ICP)were responsible for this unexpected ***,the relative contributions of IO SST and ICP soil moisture to the 2020 mei-yu rainfall event,especially their linkage with atmospheric circulation changes,remain *** using observations and numerical simulations,this study examines the synergistic impacts of IO SST and ICP soil moisture on the extreme mei-yu in *** show that the prolonged dry soil moisture led to a warmer surface over the ICP in May under strong IO SST *** intensification of the warm condition further magnified the land thermal effects,which in turn facilitated the westward extension of the western North Pacific subtropical high(WNPSH)in June‒*** intensified WNPSH amplified the water vapor convergence and ascending motion over the YRB,thereby contributing to the 2020 *** contrast,the land thermal anomalies diminish during normal IO SST backgrounds due to the limited persistence of soil *** roles of IO SST and ICP soil moisture are verified and quantified using the Community Earth System *** synergistic impacts yield a notable 32%increase in YRB *** findings provide evidence for the combined influences of IO SST forcing and ICP soil moisture variability on the occurrence of the 2020 super mei-yu.

关键词： super mei-yu Indian Ocean SST soil moisture Indochina Peninsula

A systematic framework of constructing surrogate model for slider track peeling strength prediction

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Science China Technological Sciences 2024年第10期67卷 3261-3274页

作者： dong XingJian chen Qian LIU WenBo WANG dong PENG ZhiKe MENG Guang State Key Laboratory of Mechanical System and Vibration Shanghai Jiao Tong University KEIPER Seating Mechanisms Co. Ltd. Department of Industrial Engineering and Management Shanghai Jiao Tong University

Peeling strength can comprehensively reflect slider track safety and is crucial in car seat safety assessments. Current methods for determining slider peeling strength are primarily physical testing and numerical simulation. However, these methods encounter the potential challenges of high costs and overlong time consumption which have not been adequately addressed. Therefore, the efficient and low-cost surrogate model emerges as a promising solution. Nevertheless, currently used surrogate models suffer from inefficiencies and complexity in data sampling, lack of robustness in local model predictions, and isolation between data sampling and model prediction. To overcome these challenges, this paper aims to set up a systematic framework for slider track peeling strength prediction, including sensitivity analysis, dataset sampling, and model prediction. Specifically, the interpretable linear regression is performed to identify the sensitivity of various geometric variables to peeling strength. Based on the variable sensitivity, a distance metric is constructed to measure the disparity of different variable groups. Then, the sparsity-targeted sampling(STS) is proposed to formulate a representative dataset. Finally, the sequentially selected local weighted linear regression(SLWLR) is designed to achieve accurate track peeling strength prediction. Additionally, a quantitative cost assessment of the supplementary dataset is proposed by utilizing the minimum adjacent sample distance as a mediator. Experimental results validate the efficacy of sequential selection and the weighting mechanism in enhancing localization ***, the proposed SLWLR method surpasses similar approaches and other common surrogate methods in terms of prediction performance and data quantity requirements, achieving an average absolute error of 3.3 kN in the simulated test dataset.

关键词： slider track peeling strength surrogate model sensitivity analysis data sampling local weighted linear regression

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A new phenanthraquinone from the roots of Peucedanum praeruptorum

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Chinese Chemical Letters 2010年第7期21卷 816-817页

作者： Cun Zhang Li Li Yong Qing Xiao Wen Li Xiao Jie Yin Guo Fang Tian dong dong chen Yun Wang Institute of Chinese Materia Madica China Academy of Traditional Chinese MedicineBeijing 100700China

A new compound,9,10-dihydrophenanthrinic acid,9,10-dione-3,4-methylenedioxy-8-methoxy（1） was isolated from the roots of Peucedanum praeruptorum Dunn on the basis of spectral evidences.

关键词： Peucedanum praeruptorum 9 10-Phenanthraquinone 9 10-Dihydrophenanthrinic acid 9 10-Dione-3 4-methylenedioxy-8-methoxy

Study on the force chain characteristics with coal dust layer and the three-body contact stiffness

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Particuology 2024年第9期92卷 288-304页

作者： Xinwei Yang dongxuan Wu Hongyue chen dong Wang School of Mechanical Engineering Liaoning Technical UniversityFuxin123000China Ordos Institute of Liaoning Technical University Ordos017000China School of Mining Liaoning Technical UniversityFuxin123000China China National Coal Association Dynamic Research for High-end Complete Integrated Coal Mining Equipment and Big Data Analysis CentreFuxin123000China

To explore the influence of the meso-mechanical behaviors of the wet coal dust layers on the contact stiffness of mechanical bonding surfaces,a three-body contact model incorporating an interface with wet coal dust was constructed based on breakage *** model considered the mechanical surface morphology and contact characteristics of the wet coal *** force chain evolution laws of the wet coal dust layer were elucidated under the effects of gap filling and the cover layer,and the bearing characteristics of the three-body contact bonding surfaces were revealed by quantitative analyses of the number,length,collimation coefficient,and coordination number of the force chains within the wet coal dust ***,the three-body normal contact stiffness under various preload forces was computed and experimentally *** results demonstrate that the external load transfer path of the three-body contact bonding surfaces was from mechanical surface(macroscopic stress)to wet coal dust layer(mesoscopic force chains)and then to mechanical surface(peaks and valleys).The interactions among these three elements contributed to transforming the distributions of the macroscopic stresses and mesoscopic force chains to the locations at the peaks and valleys of the mechanical *** them,the proportion of short force chains in the wet coal dust layer increased from approximately 0.8%–91%,while the proportion of long force chains exhibited an opposite changing *** force chain collimation coefficient initially increased and subsequently stabilized,reaching a maximum value of 0.93.A large number of broken,small particles in the wet coal dust layer mainly served to fill the gaps among large *** maximum relative error between the experimental and simulated values on the three-body contact stiffness is 7.26%,indicating that the simulation results can be an approximate substitute for the experimental results with a certain degree of accuracy and practic

关键词： Wet coal dust Force chain Three-body contact stiffness Gap flling effect Cover layer effect

Dual metal ions/BNQDs boost PMS activation over copper tungstate photocatalyst for antibiotic removal:Intermediate,toxicity assessment and mechanism

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Journal of Materials Science & Technology 2024年第3期170卷 11-24页

作者： Ruyao chen Haiyue Zhang Yuming dong Haifeng Shi School of Science Jiangnan UniversityWuxi214122China The Key Laboratory of Synthetic and Biological Colloids Ministry of EducationJiangnan UniversityWuxi214122China National Laboratory of Solid State Microstructures Nanjing UniversityNanjing210093China

In the metal-based peroxymonosulfate(PMS)activation process,the sluggish surface redox cycle of metal ions generally hampered the efficiency of PMS activation for pollutant ***,Codoped CuWO 4/BN quantum dots(CW/Co/BNQDs)photocatalysts were developed to realize Cu^(2+)/Cu+and Co^(2+)/Co^(3+)dual ions redox cycles for PMS activation,which would facilitate the tetracycline(TC)***/4Co/2BNQDs could degrade 94.8%TC within 30 min in PMS/Vis system,and the apparent rate constant of CW/4Co/2BNQDs was 2.7 times and 1.2 times higher than those of CW and CW/4Co,*** improved TC degradation performance could be attributed to the synergetic effect between BNQDs and dual redox cycles.X-ray photoelectron spectroscopy(XPS)spectra of samples before and after the reaction demonstrated that BNQDs were beneficial for accelerating the Cu^(2+)/Cu+and Co^(2+)/Co^(3+)redox cycles in CW/4Co/2BNQDs,further boosting the activation of PMS in TC *** of different radical scavengers revealed that the SO_(4)^(·−)/·OH/h+/^(1)O_(2)reactive species participated in the PMS activation for the TC degradation *** possible TC degradation pathway and intermediate toxicity were detailed *** addition,CW/4Co/2BNQDs exhibited outstanding photocatalytic activity over five consecutive cycles,which illustrated that it was supposed to be a reliable PMS activator over antibiotic elimination for practical *** this work shed new light on constructing dual redox cycles for efficient PMS activation.

关键词： Dual redox cycles Photocatalysis Peroxymonosulfate BN quantum dots Toxicity assessment