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Force-position collaborative optimization of rope-driven snake manipulator for capturing non-cooperative space targets

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Chinese Journal of Aeronautics 2024年第9期37卷 369-384页

作者： xiaofeng LI Jian tian Cheng WEI Xibin CAO School of Astronautics Harbin Institute of TechnologyHarbin 150001China Beijing Instiuteof Spacecraft System Engineering China Academy of Space TechnolgyBeijing 100094Chia

With the rapid development of space activities,non-cooperative space targets increase swiftly,such as failed satellites and upper stages,threating normal spacecrafts *** there are some problems in the capture process,such as excessive collision and fast tumbling of targets,manipulator with redundant Degrees of Freedom(DOFs)can be used to improve the compliance and therefore solve these *** Rope-Driven Snake Manipulator(RDSM)is a combina-tion of hyper-redundant DOFs and better compliance,and therefore it is suitable for capturing *** this paper,a snake manipulator mechanism is designed,and the complete kinematic model and system dynamic model considering RDSM,target and contact is ***,to obtain the configuration of joint with hyper-redundant DOFs,an improved motion dexterity index is pro-posed as the joint motion optimization ***,the force-position collaborative optimization index is designed to adjust active stiffness,and the impedance control method based on the modified index is used to capture the space ***,the proposed force-position collaborative opti-mization method is verified by virtual prototype *** results demonstrate that based on the proposed method,the collision force is reduced by about 25%compared to normal impe-dance control,showing higher safety.

关键词： Capturing non-cooperative spacetargets Rope-driven snakemanipu-lator Force-position collaborative optimization Redundant degrees of free-dom Active stiffness adjustment

pH-responsive metal nanoparticles as high contrast theranostic agents for selective imaging and synergistic cancer therapy

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Science China Chemistry 2024年第9期67卷 3063-3070页

作者： Sichao tian xiaofeng He Xiao Wu Dongxue Hu Qing-Hua Xu Department of Chemistry National University of SingaporeSingapore 117543Singapore National University of Singapore(Suzhou)Research Institute Suzhou 215123China Institute of Medicinal Plant Development Chinese Academy of Medical Sciences and Peking Union Medical CollegeBeijing 100050China Department of Biological Sciences Faculty of ScienceNational University of SingaporeSingapore 117558Singapore

The low signal-to-noise ratio(S/N)and single functionality of fluorescence imaging agents have limited their practical *** two-photon excitation(2PE)imaging probes are highly desirable in vivo with larger imaging depth,minor autofluorescence background,and less ***,we developed responsive aggregated gold nanoparticles(Au NPs)as high contrast 2PE imaging agents,capable of emitting red fluorescence upon excitation of near-infrared(NIR)laser and possessing a high signal-to-noise ratio(S/N of 2,475).By forming aggregates in situ inside tumor tissue,doxorubicin hydrochloride(DOX)-loaded mix-charged gold nanoparticles(DOX-MC-Au NPs)were utilized to act as selective fluorescence imaging probes and precise therapy *** high-contrast theranostic agents offer a promising potential for precise cancer imaging and therapy,which might open a new venue to multifunctional and noninvasive theranostics.

关键词： metal nanoparticles two-photon excitation high contrast imaging agents fluorescence imaging cancer therapy

Self-doping active sites in microbe-derived carbonaceous electrocatalysts for the oxygen reduction reaction performance

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Nano Research 2024年第8期17卷 6803-6819页

作者： xiaofeng Xiao Xiaochun tian Junpeng Li Fan Yang Rui Bai Feng Zhao Key Laboratory of Urban Pollutant Conversion Institute of Urban EnvironmentChinese Academy of SciencesXiamen 361021China University of Chinese Academy of Sciences Beijing 100049China

Microorganisms are rich in heteroatoms,which can be self-doped to form active sites during pyrolysis and loaded on microbederived carbonaceous *** recent years,microbe-derived carbonaceous materials,characterized with abundant selfdoping sites,have been continuously developed as cost-effective electrocatalysts for oxygen reduction reaction(ORR).To fully unlock the catalytic potential of microbe-derived carbonaceous materials,a comprehensive analysis of catalytic sites and mechanisms for ORR is *** paper provides a summary of the ORR catalytic performance of microbe-derived carbonaceous materials reported to date,with a specific focus on the self-doping sites introduced during their pyrolytic *** highlights the mono-or co-doping sites involving nonmetallic elements such as oxygen(O),nitrogen(N),phosphorus(P),and sulfur(S)atoms,as well as covers the doping of metallic iron(Fe)atoms with various coordination configurations in microbe-derived carbonaceous *** the impact of these self-doping sites on ORR catalytic performance can guide the design of doping sites in microbe-derived carbonaceous *** approach has the potential to maximize electrocatalytic activity of microbe-derived carbonaceous materials and contributes to the development of more efficient and cost-effective carbonaceous electrocatalysts.

关键词： electrocatalysis heteroatoms self-doped single atom catalyst microbe-derived carbonaceous material

Acidic electroreduction CO_(2)to formic acid via interfacial modification of Bi nanoparticles at industrial-level current

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Nano Research 2024年第7期17卷 5817-5825页

作者： tian Dong Hongdong Li Zhenhui Wang Yanling Geng Rui Chang xiaofeng tian Jianping Lai Shouhua Feng Lei Wang Key Laboratory of Eco-Chemical Engineering International Science and Technology Cooperation Base of Eco-Chemical Engineering and Green ManufacturingCollege of Chemistry and Molecular EngineeringQingdao University of Science and TechnologyQingdao 266042China Shandong Engineering Research Center for Marine Environment Corrosion and Safety Protection College of Environment and Safety EngineeringQingdao University of Science and TechnologyQingdao 266042China

Electrocatalytic CO_(2)reduction reaction(CO_(2)RR)in acidic media is a promising approach to overcome the unavoidable formation of carbonates in alkaline or neutral ***,the proton-rich environment near the catalyst surface favors hydrogen evolution reactions(HER),leading to lower energy efficiency of the desired products,especially in industrial-level current ***,quaternary ammonium cationic surfactant(cetyltrimethylammonium bromide(CTAB))was introduced into acidic electrolyte to modulate the interfacial microenvironment,which greatly enhanced CO_(2)electroreduction to formic acid(HCOOH)at the Bi/C nanoparticles *** a Bi/C nanoparticles electrode with CTAB added,constant production of formic acid was enabled with a cathodic energy efficiency of>40%and maximum FE_(HCOOH)(FE=Faradaic efficiency)of 86.2%at−400 mA·cm^(−2)over 24 *** with in-situ attenuated total reflection Fourier transform infrared spectroscopy,the concentration of*OCHO intermediates significantly increased after CTAB modification,confirming that the hydrophobic interface microenvironment formed by dynamic adsorption of positively charged long alkyl chains on Bi/C nanoparticle electrodes inhibited HER and improved the selectivity of CO_(2)RR to HCOOH.

关键词： acidic media CO_(2)electrolysis electrolyte additive hydrophobic interfacial microenvironment industrial-level current

Effect of different drying methods on the amino acids,α-dicarbonyls and volatile compounds of rape bee pollen

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Food Science and Human Wellness 2024年第1期13卷 517-527页

作者： Yanxiang Bi Jiabao Ni xiaofeng Xue Zidan Zhou Wenli tian Valérie Orsat Sha Yan Wenjun Peng Xiaoming Fang State Key Laboratory of Resource Insects Institute of Apicultural ResearchChinese Academy of Agricultural SciencesBeijing 100093China College of Engineering China Agricultural UniversityBeijing 100083China Bioresource Engineering Dept. McGill UniversitySte-Anne-de-Bellevue QC H9X 3V9Canada

The significant demand for high quality food has motivated us to adopt appropriate processing methods to improve the food nutritional quality and *** this study,the effects of five drying methods,namely,pulsed vacuum drying(PVD),freeze drying(FD),infrared drying(IRD),hot-air drying(HAD)and sun drying(SD)on free amino acids(FAAs),α-dicarbonyl compounds(α-DCs)and volatile compounds(VOCs)in rape bee pollen(RBP)were *** results showed that FD significantly released the essential amino acids(EAAs)compared with fresh samples while SD caused the highest *** was the dominantα-DCs in RBP and the highest loss was observed after *** were the dominant volatiles of RBP and SD samples contained more new volatile substances(especially aldehydes)than the other four drying ***,FD and PVD would be potential methods to effectively reduce the quality deterioration of RBP in the drying process.

关键词： Drying Bee pollen Free amino acids α-Dicarbonyl compounds Volatile compounds

The sedimentary structure characteristics and spatial distribution pattern of the Zhaoji Salt Mine derived from dense array ambient noise tomography

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Journal of Earth Science 2024年

作者： Hongwei Wang xiaofeng tian Qiaoxia Liu Jia Cheng Ming Zhou Zhiping Xu Jiyan Lin Shuaipeng Zhu Geophysics Exploration Center China Earthquake Administration School of Earth Sciences and Resources， China University of Geosciences (Beijing)

Due to the lack of the three-dimensional structure of the Zhaoji salt basin， the salt mining enterprises have obvious clustering when choosing sites. Production capacity declines rapidly as mining deepens， the enterprises are entering a stage of stagnation in production. In this study， a dense seismic array of 125 short-period stations was deployed around the core mining area and its vicinity of the salt mine industry， we use the ambient noise tomography (ANT) method to image the three-dimensional shear wave velocity structure at the depth shallower than 3 km. The results indicate: (1) The overall shear wave velocity in the study area is relatively lower， ranging from 0.8 and 1.8 km/s， which could be related to the loose and thick deposition of the Zhaoji Sub-Depression. (2) The three-dimensional shear wave velocity structure reveals that the sedimentary thickness of the Zhaoji Sub-Depression is deeper in the southeast and shallower in the northwest， with the sedimentary center located around Heping Town and Dahuangzhuang Town. (3) The Zhaoji salt mine is a low-velocity anomalous zone in the shear wave velocity structure with an inverse 'C' character spreading along Nanchenji Town and Zhaoji Town， with a depth ranging from approximately 1.2 to 2.8 km， it may be caused by the development of rock fissures due to water extraction and injection. The surrounding rock exhibits relatively high velocity， which reflects the morphological characteristics of the Zhaoji salt basin. The three-dimensional shear wave velocity model obtained in this study provides scientific guidance for the industrial exploitation of the Zhaoji salt mine and reference for salt exploration of the Hongze Salt Basin. It also provides an important basis for the seismic risk assessment of the salt basins. Simultaneously， it holds significant implications for exploring the application of ambient noise tomography method in spatial detection of salt mine belt.

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Effects of Curcumin on Neuroinflammation and the Nrf2/HO-1 Pathway in Rat Brains Following Gas Explosion

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Biomedical and Environmental Sciences 2024年第8期37卷 943-947页

作者： Xinwen Dong Yaguang Su Zheng Luo Lyufei Deng xiaofeng Han Yifang Liang Sanqiao Yao Weidong Wu Jia Cao Linqiang tian Yichun Bai Wenjie Ren Health School of Public Health Xinxiang Medical UniversityXinxiang 453003HenanChina Toxicology Research Institute PLA Army Medical UniversityChongqing 400038China Institute of Trauma and Orthopaedics Xinxiang Medical UniversityXinxiang 453003HenanChina Institutes of Health Central Plains Xinxiang Medical UniversityXinxiang 453003HenanChina

Gas explosions,a major occupational hazard in China’s coal industry,endanger the lives and health of *** explosions cause a specific type of traumatic brain injury with complex mechanisms,leading to disability and death.A study by Zhao et *** magnetic resonance imaging on 49 gas explosion survivors revealed significant damage to brain regions like the hippocampus and cerebral cortex.

关键词： damage Nrf2 cerebral

Insights into dammarane-type triterpenoid saponin biosynthesis from the telomere-totelomere genome of Gynostemma pentaphyllum

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Plant Communications 2024年第8期5卷 100-103页

作者： Lingling Yun Chuyi Zhang Tongtong Liang Yu tian Guoxu Ma Vincent Courdavault Sijie Sun Baiping Ma Ziqin Li Rucan Li Feng Cao xiaofeng Shen Jianhe Wei Ying Li Baolin Guo Chao Sun Institute of Medicinal Plant Development Chinese Academy of Medical Sciences and Peking Union Medical CollegeBeijing 100193China Biomole cules et Biotechnologies Ve ge tales EA2106Universite de Tours37200 ToursFrance Beijing Institute of Radiation Medicine Beijing 100850China Present address:National Genomics Data Center Beijing Institute of GenomicsChinese Academy of Sciences and China National Center for BioinformationBeijing 100101China

Dear Editor,Gynostemma pentaphyllum(Thunb.)Makino,a perennial climbing vine in the Cucurbitaceae family,has been widely used in traditional medicine for over 600 years(Blumert and Liu,1999).It serves as a valuable natural source of over 200 dammaranetype saponins with notable bioactive properties,including anti-cancer,cardioprotective,hepatoprotective,neuroprotective,and anti-diabetic activities(Li et al.,2016;Nguyen et al.,2021).

关键词： protective Gynostemma saponins

提高规范诊疗水平改善我国大动脉炎患者的预后

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中华内科杂志 2024年第2期63卷 129-131页

作者：田新平曾小峰中国医学科学院、北京协和医学院、北京协和医院风湿免疫科、国家皮肤与免疫疾病临床医学研究中心、疑难重症及罕见病国家重点实验室风、湿免疫病学教育部重点实验室北京100730

大动脉炎(Takayasu′s ***)是我国最常见的成人大血管炎,以青年女性最常见,初步估计我国现有患病人群5万。由于TAK少见,我国存在对其早期诊断意识薄弱,对疾病的评估不全面,对影像学检查结果缺乏正确的认识,多学科协作程度欠佳,治疗规范... 详细信息

大动脉炎(Takayasu′s ***)是我国最常见的成人大血管炎,以青年女性最常见,初步估计我国现有患病人群5万。由于TAK少见,我国存在对其早期诊断意识薄弱,对疾病的评估不全面,对影像学检查结果缺乏正确的认识,多学科协作程度欠佳,治疗规范程度低,缺乏大规模高质量临床研究等现象。望此次制定的《中国大动脉炎诊疗指南(2023)》能提高我国TAK诊治规范化水平,改善患者预后。

关键词：大动脉炎诊断治疗