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Polygonatum sibiricum polysaccharides attenuated colitis via regulating gut microbiota mediated colonic NLRP3/ASC/Caspase-1/GSDMD signaling pathway
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作者 Zhongyu Yuan Xinyu Wang +9 位作者 Jun Wang Yuan Xu Jing chen Shuqi Yu zhiming chen Peilu chen Jixiao Zhu Weifeng Huang Guanghui Xu Litao Yi 《Food Science and Human Wellness》 2025年第12期5035-5052,共18页
Polygonatum sibiricum has long been a popular functional food in Asia,known for its anti-inflammatory properties.However,its efficacy in alleviating colitis has yet to be investigated.This study aimed to explore the t... Polygonatum sibiricum has long been a popular functional food in Asia,known for its anti-inflammatory properties.However,its efficacy in alleviating colitis has yet to be investigated.This study aimed to explore the therapeutic potential of P.sibiricum polysaccharides(PSP)in dextran sulfate sodium(DSS)-induced colitis,focusing on the related pyroptosis mechanisms.Scanning electron microscopy(SEM)analysis showed that PSP possesses a smooth surface with no pore structure and a dense,lamellar structure adorned with numerous spherical entities.PSP treatment significantly reduced colitis symptoms and decreased pro-inflammatory cytokines,likely through suppression of the Toll like receptor 4(TLR4)/nuclear factor KB(NF-κB)signaling pathway.Additionally,PSP attenuated NOD-like receptor protein 3(NLRP3)/apoptosis-associated speck-like protein containing a CARD(ASC)/Caspase-1/Gasdermin D(GSDMD)-mediated pyroptosis and mitochondria damage in the colon,while enhanced the expression of tight junction and adherens junction proteins.Microbiota sequencing showed that PSP increased the abundance of phylum Bacteroidota and genus such as g_unclassified_f_Muribaculaceae,Lactobacillus,Clostridia_UCG-014,and Lachnospiraceae_NK4A136_group,while decreased the phylum Proteobacteria and the genus Enterobacter,Escherichia-Shigella,and Blautia.In conclusion,this study demonstrates that PSP exerts the potential therapeutic role against colitis,which was mediated by the regulation of gut microbiota and the inhibition of colonic NLRP3/ASC/Caspase-1/GSDMD signaling pathway. 展开更多
关键词 Polygonatum sibiricum COLITIS Inflammation NOD-like receptor protein 3 Gut microbiota Intestinal barrier
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High precision attitude dynamic tracking control of a moving space target 被引量:7
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作者 Yunhua WU Mohong ZHENG +3 位作者 Wei HE Feng WANG zhiming chen Bing HUA 《Chinese Journal of Aeronautics》 SCIE EI CAS CSCD 2019年第10期2324-2336,共13页
On-orbit spacecraft face many threats,such as collisions with debris or other spacecraft.Therefore,perception of the surrounding space environment is vitally important for on-orbit spacecraft.Spacecraft require a dyna... On-orbit spacecraft face many threats,such as collisions with debris or other spacecraft.Therefore,perception of the surrounding space environment is vitally important for on-orbit spacecraft.Spacecraft require a dynamic attitude tracking ability with high precision for such missions.This paper aims to address the above problem using an improved backstepping controller.The tracking mission is divided into two phases:coarse alignment and fine alignment.In the first phase,a traditional saturation controller is utilized to limit the maximum attitude angular velocity according to the actuator’s ability.For the second phase,the proposed backstepping controller with different virtual control inputs is applied to track the moving target.To fulfill the high precision attitude tracking requirements,a hybrid attitude control actuator consisting of a Control Moment Gyro(CMG)and Reaction Wheel(RW)is constructed,which can simultaneously avoid the CMG singularity and RW saturation through the use of an angular momentum optimal management strategy,such as null motion.Finally,five simulation scenarios were carried out to demonstrate the effectiveness of the proposed control strategy and hybrid actuator. 展开更多
关键词 Space MOVING target ATTITUDE DYNAMIC tracking BACKSTEPPING controller Improved virtual control input Hybrid ACTUATOR
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Characterization of precipitation in the background of atmospheric pollutants reduction in Guilin: Temporal variation and source apportionment 被引量:8
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作者 Ling Li Hong Li +7 位作者 Liang Peng Yongshan Li Yi Zhou Fahe Chai Zhaoyu Mo zhiming chen Jingying Mao Wenxing Wang 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2020年第12期1-13,共13页
Rainfall samples were collected from three observation sites in Guilin from 2013 to 2017, and the chemical composition characteristics of precipitation and the contribution made by different ion sources were analyzed ... Rainfall samples were collected from three observation sites in Guilin from 2013 to 2017, and the chemical composition characteristics of precipitation and the contribution made by different ion sources were analyzed when atmospheric pollutants levels were reduced. The results showed that acid gas emissions and atmospheric pollutant concentrations continued to decline during the study period. However, the change in the volume-weighted mean p H at the three sites suggested that acid rain pollution was not alleviated and began to deteriorate after 2015. The continuing downward trend for alkaline neutralizing ions(Ca^(2+), NH_4^+) in precipitation indicated that the reduction in alkaline neutralizing substances in the atmosphere was an important factor that led to the deterioration in acid rain across Guilin. The principal component analysis and spearman correlation analysis indicated five sources of ions in precipitation. Quantitative assessment of these five sources indicated that fossil fuel combustion contributed the most ions concentration in precipitation at the three sites, followed by agriculture, terrestrial(crustal) sources, marine sources, and biomass burning. Long-distance airflow might affect the acidity, the electrical conductivity(EC), and ion concentrations in precipitation across Guilin. The airflow trajectory from the west and southeast directions corresponded to higher acidity and ion concentrations. According to the current air pollution control strategy planned by Guilin, reducing atmospheric coarse particles and NH_3 at the same time may potentially lead to further deteriorations in acid rain contents. Therefore, Guilin needs to develop more reasonable pollution prevention measures that synergistically control atmospheric pollutants and acid rain pollution. 展开更多
关键词 Precipitation chemistry CHARACTERIZATION Source contributions Synergistic control GUILIN
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局部T晚期与N晚期鼻咽癌患者的预后比较 被引量:10
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作者 蒋朝阳 王娟 +4 位作者 陈治明 张伶 高辉 张涛 李智慧 《中国肿瘤临床》 CAS CSCD 北大核心 2020年第15期780-783,共4页
目的:回顾性分析局部T晚期与N晚期鼻咽癌患者的预后情况,为临床鼻咽癌治疗提供参考.方法:选取2011年12月至2017年11月西部战区总医院经病理确诊为鼻咽癌的局部T晚期患者102例、局部N晚期患者162例的临床病例资料,分为两组并分析患者的... 目的:回顾性分析局部T晚期与N晚期鼻咽癌患者的预后情况,为临床鼻咽癌治疗提供参考.方法:选取2011年12月至2017年11月西部战区总医院经病理确诊为鼻咽癌的局部T晚期患者102例、局部N晚期患者162例的临床病例资料,分为两组并分析患者的预后情况.结果:局部T晚期与N晚期患者5年总生存率(overall survival,OS)分别为82.8%与75.8%(P=0.271)、无疾病进展生存率(progression-free survival,PFS)分别为73.7%与62.8%(P=0.043),无局部复发生存率(local relapse-free survival,LRFS)分别为87.6%与91.6%(P=0.646)、无远处转移生存率(distant metastasis-free survival,DMFS)分别为87.7%与79.5%(P=0.066),两组间PFS差异具有统计学意义.结论:局部N晚期鼻咽癌患者的DMFS、OS、PFS均有下降趋势,临床上局部N晚期鼻咽癌患者应更强调系统性治疗以及分层治疗的意义,以争取更高的OS并降低远处转移. 展开更多
关键词 鼻咽癌 T晚期 N晚期 预后
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Molybdosphoric Acid Mixed with Titania Used as a Catalyst to Synthesize Diphenyl Carbonate via Transesterification of Dimethyl Carbonate and Phenol 被引量:7
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作者 Tong chen Huajun Han +5 位作者 Zhiping Du Jie Yao Gongying Wang Dachuan Shi Desheng Zhang zhiming chen 《Journal of Natural Gas Chemistry》 EI CAS CSCD 2006年第4期303-306,共4页
The 12-molybdosphoric acid mixed with titania (MPA-TiO2) was found to be a novel and efficient catalyst for the synthesis of diphenyl carbonate (DPC) via transesterification of dimethyl carbonate (DMC) and pheno... The 12-molybdosphoric acid mixed with titania (MPA-TiO2) was found to be a novel and efficient catalyst for the synthesis of diphenyl carbonate (DPC) via transesterification of dimethyl carbonate (DMC) and phenol. The X-ray diffraction (XRD) and infrared (IR) techniques were employed to characterize the prepared catalysts. The effect of the weight ratio of the 12-molybdosphoric acid to titania on the transesterification was investigated. A 13.1% yield of DPC and an 11.6% yield of methyl phenyl carbonate (MPC) were obtained over MPA-TiO2 with the weight ratio of MPA to TiO2 as 5:1. 展开更多
关键词 TRANSESTERIFICATION 12-molybdosphate acid TITANIA methyl phenyl carbonate diphenyl carbonate
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Singularity analysis for single gimbal control moment gyroscope system using space expansion method 被引量:5
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作者 Yunhua WU Feng HAN +2 位作者 Bing HUA zhiming chen Feng YU 《Chinese Journal of Aeronautics》 SCIE EI CAS CSCD 2018年第4期782-794,共13页
Control Moment Gyroscope(CMG) is an effective candidate for agile satellites and large spacecraft attitude control because of its powerful torque amplification capability. The most serious situation, however, in usi... Control Moment Gyroscope(CMG) is an effective candidate for agile satellites and large spacecraft attitude control because of its powerful torque amplification capability. The most serious situation, however, in using CMG is the inherent geometric singularity problem, where there's no torque output along a particular direction. Space expansion method has been proposed in this work for the singularity analysis. Based on inverse mapping transformation, an expanded Jacobian matrix which is a full rank square matrix is obtained. The singular angle sets of the 3-parallel cluster and pyramid cluster are distinguished using space expansion method. An effective hybrid steering strategy, able to deal with the elliptic singularity, is further proposed. Simulation results demonstrate the excellent performance of the proposed steering logic compared to the generalized singular robust logic and pseudo inverse logic in terms of energy consumption and torque error. 展开更多
关键词 Agile spacecraft Control moment gyro Singularity analysis Space expansion method Steering strategy
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Review:A Survey of Single Gimbal Control Moment Gyroscope forAgile Spacecraft Attitude Control 被引量:4
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作者 Yunhua Wu Feng Han +3 位作者 Bing Hua zhiming chen Dafu Xu Linlin Ge 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 2018年第6期22-45,共24页
Agile attitude maneuver is a basic requirement for next generation imaging spacecraft and Control Moment Gyroscope (CMG) is an effective candidate for large space station and agile spacecraft attitude control because ... Agile attitude maneuver is a basic requirement for next generation imaging spacecraft and Control Moment Gyroscope (CMG) is an effective candidate for large space station and agile spacecraft attitude control because of its torque amplification capability. This paper provides a thorough survey of Single Gimbal Control Moment Gyroscope (SGCMG) in terms of configuration,evaluation,modeling,singularity analysis and steering logic,etc. For specific space missions,CMGs are logically mounted into different particular arrays which can be chosen by the proposed evaluation methods. From the dynamic model we find a tough inverse mapping problem which suffers the inherent geometric singularity. Different techniques and theories then are applied for singularity analysis and CMG steering logics design. The pyramid CMG cluster and singular robust logics are proven to be able to enhance the agility of spacecraft. Above work forms a systematic framework of SGCMG for agile spacecraft control with lots of illustrative examples,tables and figures,and will evoke further investigation for future missions. 展开更多
关键词 AGILE SPACECRAFT SGCMG CMG configuration SINGULARITY and STEERING logic
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Highly time-resolved aerosol characteristics during springtime in Weizhou Island 被引量:2
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作者 Jingying Mao zhiming chen +7 位作者 Zhaoyu Mo Xiaoyang Yang Hong Li Yonglin Liu Huilin Liu Jiongli Huang Junchao Yang Hongjiao Li 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2018年第10期64-74,共11页
A single particle aerosol mass spectrometer was deployed to measure the changes of single particle species and sizes during March 2015 in Weizhou Island of the Beibu Gulf, Guangxi province, South China. In this campai... A single particle aerosol mass spectrometer was deployed to measure the changes of single particle species and sizes during March 2015 in Weizhou Island of the Beibu Gulf, Guangxi province, South China. In this campaign, a total of 3,100,597 particles were sized, and 25.8%particles with both positive and negative mass spectrum were collected and 24.8%characterized in combination with the ART-2 a neural network algorithm. The distribution of sized particles was mainly in from 520 to 600 nm, and the diameters ranging from 340 to1000 nm accounted for above 90%. Eight types of particles were classified: Elemental Carbon containing(EC), Organic Carbon containing(OC), EC and OC combined containing particles,Na containing particles, K containing particles(K), Levoglucosan containing particles,mineral containing particles, and Heavy Metal containing particles(HM). EC, OC and K were the major containing particles, which accounted for 84.3% in the eight types particles. The relative ratio and size distribution of the three types were EC(48.1%, 620 nm), OC(12.7%,440 nm), and K(23.5%, 600 nm), respectively. The three types of particles were a bit increasing ratios compared with those in clean periods during haze pollution periods.Combined with the back-trajectory results from the Hysplit-4 model and local pollution sources revealed that the ambient air quality on the Weizhou Island may be influenced by biomass burning in the Indochina Peninsula(biomass burning in the Indochina Peninsula)from the transportation on higher level atmospheric layer and by mainland of south China located northeast of Weizhou Island on the ground. 展开更多
关键词 CHARACTERISTICS TRANSPORTATION Single particle aerosol mass SPECTROMETER Biomass burning Weizhou Island
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Online single particle measurement of fireworks pollution during Chinese New Year in Nanning 被引量:4
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作者 Jingyan Li Tingting Xu +9 位作者 Xiaohui Lu Hong chen Sergey A.Nizkorodov Jianmin chen Xin Yang Zhaoyu Mo zhiming chen Huilin Liu Jingying Mao Guiyun Liang 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2017年第3期184-195,共12页
Time-resolved single-particle measurements were conducted during Chinese New Year in Nanning, China. Firework displays resulted in a burst of SO2, coarse mode, and accumulation mode (100-500 nm) particles. Through s... Time-resolved single-particle measurements were conducted during Chinese New Year in Nanning, China. Firework displays resulted in a burst of SO2, coarse mode, and accumulation mode (100-500 nm) particles. Through single particle mass spectrometry analysis, five different types of particles (fireworks-metal, ash, dust, organic carbon-sulfate (OC-sulfate), biomass burning) with different size distributions were identified as primary emissions from firework displays. The fireworks-related particles accounted for more than 70% of the total analyzed particles during severe firework detonations. The formation of secondary particulate sulfate and nitrate during firework events was investigated on single particle level. An increase of sulfite peak (80SO3) followed by an increase of sulfate peaks (97HSO7+96SO7) in the mass spectra during firework displays indicated the aqueous uptake and oxidation of SO2 on particles. High concentration of gaseous SO2, high relative humidity and high particle loading likely promoted SO2 oxidation. Secondary nitrate formed through gas-phase oxidation of NO2 to nitric acid, followed by the condensation into particles as ammonium nitrate. This study shows that under worm, humid conditions, both primary and secondary aerosols contribute to the particulate air pollution during firework displays. 展开更多
关键词 Chinese New YearFireworksParticle typesSecondary process
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Derivation and validation of a similarity law for free-flight wind tunnel tests of parallel stage separation 被引量:1
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作者 zhiming chen Fei XUE +4 位作者 Haichuan YU Yuchao WANG Zenghui JIANG Wei LU Lei DONG 《Chinese Journal of Aeronautics》 SCIE EI CAS CSCD 2023年第8期91-100,共10页
Aiming at the safety problem of the stage separation of parallel reusable high-speed air vehicles,this paper studies the unsteady test method and focuses on deriving a similarity law of parallel stage separation free-... Aiming at the safety problem of the stage separation of parallel reusable high-speed air vehicles,this paper studies the unsteady test method and focuses on deriving a similarity law of parallel stage separation free-flight wind tunnel tests.The new similarity law considers the influences of aerodynamic force and gravity on the motions of the two stages,as well as the influence of aerodynamic interference between the two stages on each other’s motion.From the perspective of multiangle physical equations,the conditions to ensure that the two-stage separation trajectory of a wind tunnel test is similar to that of a real air vehicle are derived innovatively,so as to ensure the authenticity and credibility of wind tunnel test results.The similarity law is verified by an HIFiRE-5 air vehicle,and the separation trajectories of wind tunnel tests and the real air vehicle are obtained by numerical simulation.The research shows that the similarity law derived in this paper can ensure that wind tunnel free-flight tests have the ability to predict the two-stage separation characteristics of real parallel vehicles.By analyzing the separation trajectory curve of the typical state,it is found that the new method can ensure that the trajectory error of a wind tunnel test does not exceed 1%,which indicates that this method is credible.The establishment of the new method lays the foundation for subsequent wind tunnel tests and provides support for research on the safety of the stage separation of parallel reusable air vehicles. 展开更多
关键词 Droptesting in wind tunnel Free-flight wind tunnel test Multi-body separation Parallel stage separation Similaritylaw
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Biocatalytic enhancement of laccase immobilized on ZnFe_(2)O_(4) nanoparticles and its application for degradation of textile dyes 被引量:1
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作者 Yuhang Wei Qingpeng Zhu +3 位作者 Weiwei Xie Xinyue Wang Song Li zhiming chen 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2024年第4期216-223,共8页
Efficient and convenient treatment of industrial dyeing wastewater is of great significance to guarantee human and animal health.This work presented the enhanced catalytic activity at pH 3.0 of laccase immobilized on ... Efficient and convenient treatment of industrial dyeing wastewater is of great significance to guarantee human and animal health.This work presented the enhanced catalytic activity at pH 3.0 of laccase immobilized on amino-functionalized ZnFe_(2)O_(4) nanoparticles(ZnFe_(2)O_(4)-laccase)and its application for the degradation of textile dyes.Due to the existence of a large number of oxygen vacancies on the surface of the ZnFe_(2)O_(4) nanoparticles,negative ions accumulated on the magnetic carriers,which resulted in a harsh optimal pH value of the ZnFe_(2)O_(4)-laccase.Laccase activity assays revealed that the ZnFe_(2)O_(4)-laccase possessed superior pH and thermal stabilities,excellent reusability,and noticeable organic solvent tolerance.Meanwhile,the ZnFe_(2)O_(4) laccase presented efficient and sustainable degradation of high concentrations of textile dyes.The initial decoloration efficiencies of malachite green(MG),brilliant green(BG),azophloxine,crystal violet(CV),reactive blue 19(RB19),and procion red MX-5B were approximately 99.1%,95.0%,93.3%,87.4%,86.1%,and 85.3%,respectively.After 10 consecutive reuses,the degradation rates of the textile dyes still maintained about 98.2%,92.5%,83.2%,81.5%,79.8%and 65.9%,respectively.The excellent dye degradation properties indicate that the ZnFe_(2)O_(4)-laccase has a technical application in high concentrations of dyestuff treatment. 展开更多
关键词 ZnFe_(2)O_(4)-laccase Catalytic activity Stability and reusability Degradation of textile dye
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Transcriptomic,proteomic,and phosphoproteomic analyses reveal dynamic signaling networks influencing long-grain rice development
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作者 Fangyu chen Yongsheng Wang +8 位作者 Zesen Zhang Xiaolong chen Jinpeng Huang zhiming chen Jingsheng Zheng Liangrong Jiang Yumin Huang Houcong Wang Rongyu Huang 《The Crop Journal》 SCIE CSCD 2022年第3期716-728,共13页
The LGS1(Large grain size 1)gene,also known as GS2/GL2/Os GRF4,is involved in regulating grain size and quality in rice,but the mechanism governing grain size has not been elucidated.We performed transcriptomic,proteo... The LGS1(Large grain size 1)gene,also known as GS2/GL2/Os GRF4,is involved in regulating grain size and quality in rice,but the mechanism governing grain size has not been elucidated.We performed transcriptomic,proteomic,and phosphoproteomic analyses of young rice panicles in Samba(a wild-type cultivar with extra-small grain)and NIL-LGS1(a nearly isogenic line of LGS1 with large grain in the Samba genetic background)at three developmental stages(4–6)to identify internal dynamic functional networks determining grain size that are mediated by LGS1.Differentially expressed proteins formed seven highly functionally correlated clusters.The concordant regulation of multiple functional clusters may be key features of the development of grain length in rice.In stage 5,16 and 24 phosphorylated proteins were significantly up-regulated and down-regulated,and dynamic phosphorylation events may play accessory roles in determining rice grain size by participating in protein–protein interaction networks.Transcriptomic analysis in stage 5 showed that differentially expressed alternative splicing events and dynamic gene regulatory networks based on 39 transcription factors and their highly correlated target genes might contribute to rice grain development.Integrative multilevel omics analysis suggested that the regulatory network at the transcriptional and posttranscriptional levels could be directly manifested at the translational level,and this analysis also suggested a regulatory mechanism,regulation of protein translation levels,in the biological process that extends from transcript to protein to the development of grain.Functional analysis suggested that biological processes including MAPK signaling,calcium signaling,cell proliferation,cell wall,energy metabolism,hormone pathway,and ubiquitin-proteasome pathway might be involved in LGS1-mediated regulation of grain length.Thus,LGS1-mediated regulation of grain size is affected by dynamic transcriptional,posttranscriptional,translational and posttranslational changes. 展开更多
关键词 PROTEOME PHOSPHOPROTEOME Transcriptome LGS1/GS2/GL2/Os GRF4 Young panicle Rice(Oryza sativa L.) Grain size
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Multi-Feature Fusion Based Relative Pose Adaptive Estimation for On-Orbit Servicing of Non-Cooperative Spacecraft
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作者 Yunhua Wu Nan Yang +1 位作者 zhiming chen Bing Hua 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 2019年第6期19-30,共12页
On-orbit servicing, such as spacecraft maintenance, on-orbit assembly, refueling, and de-orbiting, can reduce the cost of space missions, improve the performance of spacecraft, and extend its life span. The relative s... On-orbit servicing, such as spacecraft maintenance, on-orbit assembly, refueling, and de-orbiting, can reduce the cost of space missions, improve the performance of spacecraft, and extend its life span. The relative state between the servicing and target spacecraft is vital for on-orbit servicing missions, especially the final approaching stage. The major challenge of this stage is that the observed features of the target are incomplete or are constantly changing due to the short distance and limited Field of View (FOV) of camera. Different from cooperative spacecraft, non-cooperative target does not have artificial feature markers. Therefore, contour features, including triangle supports of solar array, docking ring, and corner points of the spacecraft body, are used as the measuring features. To overcome the drawback of FOV limitation and imaging ambiguity of the camera, a "selfie stick" structure and a self-calibration strategy were implemented, ensuring that part of the contour features could be observed precisely when the two spacecraft approached each other. The observed features were constantly changing as the relative distance shortened. It was difficult to build a unified measurement model for different types of features, including points, line segments, and circle. Therefore, dual quaternion was implemented to model the relative dynamics and measuring features. With the consideration of state uncertainty of the target, a fuzzy adaptive strong tracking filter( FASTF) combining fuzzy logic adaptive controller (FLAC) with strong tracking filter(STF) was designed to robustly estimate the relative states between the servicing spacecraft and the target. Finally, the effectiveness of the strategy was verified by mathematical simulation. The achievement of this research provides a theoretical and technical foundation for future on-orbit servicing missions. 展开更多
关键词 on-orbit servicing non-cooperative spacecraft multi-feature fusion fuzzy adaptive filter dual quaternion
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Kinetics Research on In-situ Rapid Dechlorination of 1,4-dichlorobenzene by Microwave-assisted Raney Ni-Al Alloy Catalyst
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作者 zhiming chen Zhaoyu Mo +2 位作者 Baoying Lv Hong Xie Li Tang 《Meteorological and Environmental Research》 CAS 2013年第9期39-42,46,共5页
[Objective]The research aimed to study rapid dechlodnation kinetics of 1,4-dichlorobenzene (1,4-DCB) by microwave-assisted Raney Ni -AI alloy catalyst. [ Method] Microwave-assisted Raney Ni -AI alloy catalyst was us... [Objective]The research aimed to study rapid dechlodnation kinetics of 1,4-dichlorobenzene (1,4-DCB) by microwave-assisted Raney Ni -AI alloy catalyst. [ Method] Microwave-assisted Raney Ni -AI alloy catalyst was used for dechlorination of chlorobenzene (CB) and 1,4-DCB to analyze dechlorination kinetics of 1,4-DCB. [ Result] Reductive dechlorination reaction of 1,4-DCB by microwave-assisted Raney Ni- AI alloy catalyst was in accordance of the two-order reaction kinetics. Reaction rate constants of 1,4-DCB dechlorination at 35 and 50 ℃ were 0.037 6 and 0.151 mol/( L . min), and the activation energy was 76.66 kJ/mol. By microwave-assisted Raney Ni - AI alloy catalyst, dechlorination rate of 1,4- DCB reached 90% at 10 rain and 35 ℃. Moreover, two chlorine atoms were removed simultaneously, reaching the target of efficient dechlorination. [ Condusion] Oechlodnation of polychlodnated organic compounds by microwave-assisted Raney Ni- AI alloy catalyst obtained good effect . 展开更多
关键词 Microwave-assisted Raney Ni -AI alloy catalyst 1 4-DCB Dechlodnation KINETICS China
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Automatic Generation of Multiple-Choice Items for Prepositions Based on Word2vec
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作者 Wenyan Xiao Mingwen Wang +2 位作者 chenlin Zhang Yiming Tan zhiming chen 《国际计算机前沿大会会议论文集》 2018年第2期8-8,共1页
关键词 Multiple-choice ITEM AUTOMATIC GENERATION Word2vec
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Enhancing non-Newtonian gravity constraint using a levitated pendulum in vacuum
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作者 Fang Xiong Leilei Guo +5 位作者 Pu Huang Xiaowen Gao zhiming chen Xunmin Zhu Tong Wu Huizhu Hu 《Fundamental Research》 2026年第1期141-148,共8页
The detection of non-Newtonian gravity is crucial for fundamental physics research and our understanding of dark energy.However,conducting an experiment that provides explicit evidence of its existence remains an ende... The detection of non-Newtonian gravity is crucial for fundamental physics research and our understanding of dark energy.However,conducting an experiment that provides explicit evidence of its existence remains an endeavour.We propose an experiment utilizing a diamagnetically levitated pendulum in vacuum to detect non-Newtonian gravity on a micrometer scale.The pendulum configuration effectively helps to shield electromagnetic force fluctuations in the vacuum levitation system.The structural parameters of the pendulum are intentionally optimized to enhance the constraint on the non-Newtonian gravity strength𝛼.The designed pendulum can be stably levitated in the diamagnetic trap thanks to its passive levitation mechanism.By conducting resonance force measurements at room temperature for a duration of 10^(4)s,we anticipate a significant improvement in the constraint on the non-Newtonian gravity strength(α≥28)within the force range of λ=7.6μm.This represents an enhancement of over three orders of magnitude compared to the current limit.This study presents a promising tool for investigating short-range forces and exploring frontier physics in tabletop laboratory. 展开更多
关键词 Non-Newtonian gravity Quantum precision measurement Levitated oscillators in vacuum Levitated pendulum Short-range force detection
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An epidermal-codeformed adhesive film for flexible PCB-based sensors towards full-body motion capture system
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作者 Min HUANG Dilong LIN +13 位作者 Xinqing chen Xiaoming ZHONG zhiming chen Fengming HU Jianye LI Junfu GAN Yihua chen Weigang ZHU Pipi LU Jinxiu WEN Pengfei LI Xin HE Bingpu ZHOU Jianyi LUO 《Science China(Technological Sciences)》 2026年第1期416-429,共14页
Flexible printed circuit boards(FPCBs)play crucial roles in wearable electronics.FPCB-based sensors can be easily integrated into motion capture systems to detect and digitize human movements.However,non-conformity be... Flexible printed circuit boards(FPCBs)play crucial roles in wearable electronics.FPCB-based sensors can be easily integrated into motion capture systems to detect and digitize human movements.However,non-conformity between sensors and human skin leads to signal distortion and motion artifacts.Herein,a polydimethylsiloxane-(Z)-sorbitan mono-9-octadecenote(PDMS-Span 80)adhesive film is developed to connect and co-deform the FPCB-based bending sensor with human skin.The PDMS-Span 80 adhesive film demonstrates a high adhesive(a higher adhesion force of 38.0 kPa),reusability(over 300 cycles),long-term stability(over 20 d),and robustness(high tolerance to washing and high temperatures).Meanwhile,the adhesive film can be stripped by a low peeling strength without skin damage and shows relatively better biocompatibility with skin.Specifically,combining the high adhesive,larger stretchability,and elasticity,and skin-like elasticity modulus,the adhesive film can co-deform with human skin.With the assistance of the PDMS-Span 80 adhesive film,the FPCB-based bending sensor not only possesses exceptional responsiveness,reliability,and durability but also eliminates the overshoot phenomenon when responding to the deformation of the skin.Successful application in a full-body motion capture for the digital twin of Chinese Kungfu demonstrated the great application promise of PDMS-Span 80 adhesive film. 展开更多
关键词 PDMS-Span 80 adhesive film FPCB-based bending sensor epidermal-codeformed full-body motion capture system digital twin
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Heterogeneous Rb-Sr isotopes in Chang'e-5/6 soils:implication for geochemical study of extraterrestrial samples
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作者 Le Zhang Guanhong Zhu +13 位作者 zhiming chen Jingyou chen Yan-Qiang Zhang Zexian Cui chengyuan Wang Haiyang Xian Xianglin Tu Jintuan Wang Qing Yang Ya-Nan Yang Pengli He Fangfang Huang Linli chen Yi-Gang Xu 《Science Bulletin》 2025年第20期3329-3332,共4页
Rubidium-Sr isotope is one of the most widely used radiogenic isotopic systems in planetary geochronology and geochemistry for tracing and dating igneous processes or events.This utility stems from the distinct geoche... Rubidium-Sr isotope is one of the most widely used radiogenic isotopic systems in planetary geochronology and geochemistry for tracing and dating igneous processes or events.This utility stems from the distinct geochemical properties of Rb and Sr,which drive substantial Rb/Sr fractionation during planetary differentiation,resulting in a large variation of ^(87)Sr/^(86)Sramong different reservoirs. 展开更多
关键词 radiogenic isotopic systems planetary geochronology geochemical study change soils extraterrestrial samples planetary differentiationresulting HETEROGENEOUS rubidium sr isotopes
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A contamination-free and low-leakage-current Cu-TSV technology enabled by engineered doublesided processing
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作者 Yigang Hao Yingtao Ding +4 位作者 Ziyue Zhang Baoyan Yang Jiaxuan Zhang Huikai Xie zhiming chen 《Microsystems & Nanoengineering》 2025年第5期565-575,共11页
Through-silicon vias(TSVs)are crucial to the heterogeneous integration of multi-functional chiplets,providing highperformance vertical interconnects between different device layers.In this work,we introduce a novel TS... Through-silicon vias(TSVs)are crucial to the heterogeneous integration of multi-functional chiplets,providing highperformance vertical interconnects between different device layers.In this work,we introduce a novel TSV fabrication technology based on double-sided processing of polyimide-Ni(PI-Ni)functional layers,which can greatly simplify the TSV manufacturing flow,accompanying by advantages in improving TSV performance and reliability by effectively eliminating Cu contamination and significantly reducing leakage current.The key advancements of this approach include:(i)the complete coverage of the substrate with through-holes by the optimized double-sided PI insulation layer deposition process,where the chemical mechanical polishing(CMP)is carried out prior to the TSV metallization thus preventing substrate exposure to metallic contaminants;(ii)the deposition of a continuous Ni layer through an optimized double-sided electroless plating process,serving as both the barrier and the seed layer with high step coverage,enabling the simultaneous electroplating of TSV Cu conductors and double-sided redistribution layers(RDLs);and(iii)the demonstration of simulations and experimental validations highlighting improved thermomechanical stress distribution and superior electrical performance,including reduced parasitic capacitance and ultralow leakage current.The engineered PI-Ni-based TSV fabrication technology offers a contamination-free Cuinterconnect solution for advanced post-Moore applications such as hetero-integrated microsystems containing IC chips and MEMS devices. 展开更多
关键词 double sided processing silicon vias chiplets contamination free heterogeneous integration low leakage current Cu TSV eliminating cu contamination
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Key imidazolyl groups that induce phenylalanine flipping enhance the efficacy of oral BRD9 inhibitors for AML treatment
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作者 zhiming chen cheng Zhang +11 位作者 Hui Shen Hongrui Xu Yumin Huang Ruibo Dong Xin Tang Shuang Chai Junhua Li Jinxin Xu Xiaohan Zhang Yan Zhang Xishan Wu Yong Xu 《Acta Pharmaceutica Sinica B》 2025年第12期6546-6570,共25页
The bromodomain-containing protein 9(BRD9)is a core subunit of mammalian SWI/SNF chromatin remodeling complex termed ncBAF.BRD9 has emerged as a potential target for anticancer drugs,particularly in the treatment of a... The bromodomain-containing protein 9(BRD9)is a core subunit of mammalian SWI/SNF chromatin remodeling complex termed ncBAF.BRD9 has emerged as a potential target for anticancer drugs,particularly in the treatment of acute myeloid leukemia(AML).Herein,we reported 10m(Y22073)and 10t as new BRD9 selective bromodomain inhibitors.Crystallographic studies revealed that the key active imidazolyl group discovered from structure-activity relationship(SAR)can induce Phe163 flipping and significantly enhance the cellular potency of the compounds,making 10m the first BRD9 selective inhibitor with significant cellular activity against AML cells.We also validated the critical role of imidazolyl groups by modifying existing BRD9 inhibitors.The representative compounds 10m and 10t demonstrated potent binding affinity,outstanding selectivity toward BRD9 bromodomain,and significantly inhibited the proliferation of AML cell lines.10m also showed good metabolic stability,solubility and pharmacokinetic properties.Additionally,oral administration of compounds 10m and 10t exhibited potent anti-tumor efficacy in the MV4-11 xenograft mouse model.The potent,selective,and orally available BRD9 bromodomain inhibitors may address the challenges of weak cellular activity and limited phenotypic efficacy faced by BRD9 inhibitors,and serve as new lead compounds for the development of anticancer agents for the treatment of AML. 展开更多
关键词 EPIGENETICS BROMODOMAIN BRD9 inhibitor Drug design Structure optimization Crystallographic study Imidazolyl group Acute myeloid leukemia
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