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Simplified quantitative analysis method and its application in the insitu synthesized copper-based azide chips

Defence Technology（防务技术） 2024年第2期32卷 309-316页

作者： Jie Ren Yunfeng Li Mingyu Li Xingyu Wu Jiabao Wang Qingxuan Zeng State Key laboratory of Explosion and Technology Beijing Institute of TechnologyBeijing 100081China

Copper-based azide(Cu(N_(3))2 or CuN_(3),CA)chips synthesized by in-situ azide reaction and utilized in miniaturized explosive systems has become a hot research topic in recent ***,the advantages of in-situ synthesis method,including small size and low dosage,bring about difficulties in quantitative analysis and differences in ignition capabilities of CA *** aim of present work is to develop a simplified quantitative analysis method for accurate and safe analysis of components in CA chips to evaluate and investigate the corresponding ignition *** this work,Cu(N_(3))2 and CuN_(3)components in CA chips were separated through dissolution and distillation by utilizing the difference in solubility and corresponding content was obtained by measuring N_(3)-concentration through *** spectrophotometry method was optimized by studying influencing factors and the recovery rate of different separation methods was studied,ensuring the accuracy and reproducibility of test *** optimized method is linear in range from 1.0-25.0 mg/L,with a correlation coefficient R^(2)=0.9998,which meets the requirements of CA chips with a milligram-level content *** with the existing ICP method,component analysis results of CA chips obtained by spectrophotometry are closer to real component content in samples and have satisfactory ***,as its application in miniaturized explosive systems,the ignition ability of CA chips with different component contents for direct ink writing CL-20 and the corresponding mechanism was *** study provided a basis and idea for the design and performance evaluation of CA chips in miniaturized explosive systems.

关键词： Copper-based azide chips Spectrophotometry Separation method Quantitative analysis Ignition ability

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Singularity analysis and avoidance for an SSRMS-type reconfigurable space manipulator with a non-spherical wrist and two lockable passive telescopic links

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Chinese Journal of Aeronautics 2024年第8期37卷 435-459页

作者： Zhiyuan ZHAO Xiaohang YANG Yuntao LI Zichun XU Jingdong ZHAO Hong LIU State Key laboratory of Robotics and System Harbin Institute of TechnologyHarbin 150001China

This study focuses on addressing kinematic singularity analysis and avoidance issues for a space station remote manipulator system(SSRMS)-type reconfigurable space *** manipulator is equipped with a non-spherical wrist and two lockable passive telescopic links(LPTLs),which enable it to have both active revolute and passive prismatic joints and operate in two distinct *** begin with the kinematic singularity analysis,the study derives the differential kinematic equations for the manipulator and identifies the dominant Jacobian matrix that causes ***,an in-depth analysis of singularities from multiple perspectives is ***,a kinematic singularity map method is proposed to capture the distribution of singularities within the reachable ***,the influence of the two LPTLs on singularities is thoroughly ***,a new method based on the matrix rank equivalence principle is introduced to determine singularity conditions,enabling the identification of all the singular configurations for the SSRMS-type reconfigurable ***,this method significantly reduces computational complexity,and the singularity conditions obtained have more concise *** the singularity avoidance problem,a novel method is developed,which simultaneously addresses the requirements of real-time performance,high precision,and the avoidance of both kinematic singularities and joint limit *** from these excellent properties,the proposed method can effectively resolve the singularity issues encountered separately by the SSRMS-type reconfigurable manipulator in its two operational *** typical simulations validate the utility of all the proposed methods.

关键词： Reconfigurable space manipulator Redundant manipulator Kinematics Singularity analysis Singularity avoidance

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Comparative analysis of frictional behavior and mechanism of molybdenum ditelluride with different structures

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Friction 2024年第1期12卷 110-119页

作者： Lina ZHANG Xinfeng TAN Jianguo JIAO Dan GUO Jianbin LUO State Key laboratory of Tribology in Advanced Equipment Tsinghua UniversityBeijing 100084China

Two-dimensional(2D)transition metal dichalcogenides(TMDCs)have layered structures with excellent tribological *** the energy difference between hexagonal-molybdenum ditelluride(2H-MoTe_(2))and distorted octahedral-molybdenum ditelluride(1T′-MoTe_(2))is very small among the transition metal dichalcogenides(TMDCs),MoTe_(2) becomes one of the most promising candidates for phase *** our experiment,we found that the friction force and friction coefficient(COF)of 2H-MoTe_(2) were an order of magnitude smaller than those of 1T′-MoTe_(2) by the atomic force microscope(AFM)*** friction difference between 1T′-MoTe_(2) and 2H-MoTe_(2) was further verified in molecular dynamics(MD)*** density functional theory(DFT)calculations suggest that the friction contrast is related to the difference in sliding energy barrier of the potential energy surface(PES)for a tip sliding across the *** PES obtained from the DFT calculation indicates that the maximum energy barrier and the minimum energy path(MEP)energy barrier of 2H-MoTe_(2) are both smaller than those of 1T′-MoTe_(2),which means that less energy needs to be dissipated during the sliding *** difference in energy barrier of the PES could be ascribed to its larger interlayer spacing and weaker Mo–Te interatomic interactions within the layers of 2H-MoTe_(2) than those of 1T′-MoTe_(2).The obvious friction difference between 1T′-MoTe_(2) and 2H-MoTe_(2) not only provides a new non-destructive means to detect the phase transition by the AFM,but also provides a possibility to tune friction by controlling the phase transition,which has the potential to be applied in extreme environments such as space lubrication.

关键词： friction two-dimensional(2D)materials distorted octahedral-molybdenum ditelluride(1T′-MoTe_(2)) hexagonal-molybdenum ditelluride(2H-MoTe_(2)) phase transition

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analysis of RNA Recognition and Binding Characteristics of OsCPPR1 Protein in Rice

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Rice science 2024年第2期31卷 215-225,I0032-I0035页

作者： ZHENG Shaoyan CHEN Junyu LI Huatian LIU Zhenlan LI Jing ZHUANG Chuxiong State Key laboratory for Conservation and Utilization of Subtropical Agro-Bioresources/Guangdong laboratory for Lingnan Modern Agriculture/College of Life Sciences South China Agricultural UniversityGuangzhou 510642China

Pentatricopeptide repeat(PPR)proteins represent one of the largest protein families in plants and typically localize to organelles like mitochondria and *** contrast,CYTOPLASMLOCALIZED PPR1(OsCPPR1)is a cytoplasm-localized PPR protein that can degrade OsGOLDENLIKE1(OsGLK1)mRNA in the tapetum of rice ***,the mechanism,by which OsCPPR1 recognizes and binds to OsGLK1 transcripts,remains *** protein structure prediction and macromolecular docking experiments,we observed that distinct PPR motif structures of OsCPPR1 exhibited varying binding efficiencies to OsGLK1 ***,RNA-electrophoretic mobility shift assay experiment demonstrated that the recombinant OsCPPR1 can directly recognize and bind to OsGLK1 mRNA in *** further confirmed that the mutations in the conserved amino acids in each PPR motif resulted in loss of activity,while truncation of OsCPPR1 decreased its binding *** findings collectively suggest that it may require some co-factors to assist in cleavage,a facet that warrants further exploration in subsequent studies.

关键词： OsCPPR1 RNA recognition and binding pentatricopeptide repeat rice

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GWAS unravels acid phosphatase ACP2 as a photosynthesis regulator under phosphate starvation conditions through modulating serine metabolism in rice

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Plant Communications 2024年第7期5卷 106-119页

作者： Sushuang Liu Zhan Xu Jemaa Essemine Yanmin Liu Chundong Liu Feixue Zhang Zubair Iqbal Mingnan Qu Jiangsu Key laboratory of Crop Genetics and Physiology/Jiangsu Key laboratory of Crop Cultivation and Physiology Agricultural College of Yangzhou UniversityYangzhou 225009China Department of Life Sciences and Health Huzhou CollegeHuzhou 313000China Shenzhen Branch Guangdong Laboratory of Lingnan Modern AgricultureGenome Analysis Laboratory of the Ministry of Agriculture and Rural AffairsAgricultural Genomics Institute at ShenzhenChinese Academy of Agricultural SciencesShenzhen 518120China Institute of Crop Huzhou Academy of Agricultural SciencesHuzhou 313000China These authors contributed equally to this article

Inorganic phosphorus(Pi)deficiency significantly impacts plant growth,development,and photosynthetic *** study evaluated 206 rice accessions from a MiniCore population under both Pi-sufficient(Pi^(+))and Pi-starvation(Pi^(-))conditions in the field to assess photosynthetic phosphorus use efficiency(PPUE),defined as the ratio of A_(sat)^(Pi^(-))to A_(sat)^(Pi^(+)).A genome-wide association study and differential gene expression analyses identified an acid phosphatase gene(ACP2)that responds strongly to phosphate *** and knockout of ACP2 led to a 67%increase and 32%decrease in PPUE,respectively,compared with wild *** of an elite allele A,by substituting the v5 SNP G with A,resulted in an 18%increase in PPUE in gene-edited ACP2 rice *** phosphate-responsive gene PHR2 was found to transcriptionally activate ACP2 in parallel with PHR2 overexpression,resulting in an 11%increase in *** assays indicated that ACP2 primarily catalyzes the hydrolysis of phosphoethanolamine and *** addition,serine levels increased significantly in the ACP2^(vBG)overexpression line,along with a concomitant decrease in the expression of all nine genes involved in the photorespiratory *** of serine enhanced PPUE and reduced photorespiration rates in ACP2 mutants under Pi-starvation *** deduce that ACP2 plays a crucial role in promoting photosynthesis adaptation to Pi starvation by regulating serine metabolism in rice.

关键词： phosphate starvation GWAS photosynthetic adaption photosynthetic phosphate use efficiency genetic variation SNP rice

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Tjong:A transformer‐based Mahjong AI via hierarchical decision‐making and fan backward

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CAAI Transactions on Intelligence Technology 2024年第4期9卷 982-995页

作者： Xiali Li Bo Liu Zhi Wei Zhaoqi Wang Licheng Wu School of Information and Engineering Minzu University of ChinaBeijingChina Key laboratory of Ethnic Language Intelligent analysis and Security Governance of MOE Minzu University of ChinaBeijingChina Department of Computer Science New Jersey Institute of TechnologyNewarkNew JerseyUSA

Mahjong,a complex game with hidden information and sparse rewards,poses significant *** Mahjong AIs require substantial hardware resources and extensive datasets to enhance AI *** authors propose a transformer‐based Mahjong AI(Tjong)via hierarchical decision‐*** utilising self‐attention mechanisms,Tjong effectively captures tile patterns and game dynamics,and it decouples the decision pro-cess into two distinct stages:action decision and tile *** design reduces de-cision complexity ***,a fan backward technique is proposed to address the sparse rewards by allocating reversed rewards for actions based on winning *** consists of 15M parameters and is trained using approximately 0.5 M data over 7 days of supervised learning on a single server with 2 *** action decision achieved an accuracy of 94.63%,while the claim decision attained 98.55%and the discard decision reached 81.51%.In a tournament format,Tjong outperformed AIs(CNN,MLP,RNN,ResNet,VIT),achieving scores up to 230%higher than its ***-more,after 3 days of reinforcement learning training,it ranked within the top 1%on the leaderboard on the Botzone platform.

关键词： decision making deep learning deep neural networks

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Distribution of per-and polyfluoroalkyl substances in blood,serum,and urine of patients with liver cancer and associations with liver function biomarkers

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Journal of Environmental Sciences 2024年第5期139卷 418-427页

作者： Cao Dai Lin Peng Yanjie Li Zhendong Li Da Chen Fei Wang Nan Lin Department of Hepatobiliary Surgery The Third Affiliated Hospital of Sun Yat-sen UniversityGuangzhou 510630China School of Environment Guangdong Key Laboratory of Environmental Pollution and HealthJinan UniversityGuangzhou 510632China State Key laboratory of Environmental and Biological analysis Department of ChemistryHong Kong Baptist UniversityHong Kong 999077China South China Institute of Environmental Sciences MEEGuangzhou 510655China

Studies have shown that per-and polyfluoroalkyl substances(PFASs)may be hepatotoxic in animals or ***,data on clinical epidemiology are very *** this study,21PFASs were determined in patients with liver diseases,with the highest median concentrations detected in the serum sample(26.7 ng/mL),followed by blood(10.7 ng/mL)and urine(5.02 ng/mL).Higher total PFAS concentrations were found in hepatocellular carcinoma(HCC)patients compared to non-HCC patients,with significant discrepancies in serum and blood ***,significant correlations were also found among PFAS concentrations and age,gender,body mass index(BMI),and liver function biomarkers *** example,PFAS concentrations are significantly higher in males than in females;Several serum PFASs concentrations increase with age and BMI,while the serum perfluorohexane sulfonic acid(PFHxS)concentrations are negatively correlated with *** addition,multiple regression models adjusted for age,gender and BMI found that increased serum perfluorobutane sulfonic acid(PFBS),perfluoroheptane sulfonic acid(PFHpS)and perfluorohexylphosphonic acid(PFHxPA)conentrations are correlated with elevated alkaline phosphatase(ALP),aspartate aminotransferase(AST),and alpha-fetoprotein(AFP)(p<0.05).Our results provide epidemiological support for the future study on the potential clinical hepatotoxicity of PFAS.

关键词： Per-and polyfluoroalkyl substances(PFASs) Liver cancer Serum Blood Urine Liver function biomarkers

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A TRUST-REGION METHOD FOR SOLVING TRUNCATED COMPLEX SINGULAR VALUE DECOMPOSITION

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Journal of Computational Mathematics 2024年第4期42卷 999-1031页

作者： Jiaofen Li Lingchang Kong Xuefeng Duan Xuelin Zhou Qilun Luo School of Mathematics and Computing Science Guangxi Colleges and Universities Key Laboratory of Data Analysis and ComputationGuangxi Key Laboratory of Automatic Detecting Technology and InstrumentsGuilin University of Electronic TechnologyCenter for Applied Mathematics of Guangxi(GUET)Guilin 541004China School of Mathematical Sciences South China Normal UniversityGuangzhou 510000China School of Mathematics and Computing Science Guilin University of Electronic TechnologyGuilin 541004China School of Mathematics and Computing Science Guangxi Colleges and Universities Key Laboratory of Data Analysis and ComputationGuilin University of Electronic TechnologyCenter for Applied Mathematics of Guangxi(GUET)Guilin 541004China School of Mathematics and Statistics Yunan UniversityKunming 650000China

The truncated singular value decomposition has been widely used in many areas of science including engineering,and statistics,*** this paper,the original truncated complex singular value decomposition problem is formulated as a Riemannian optimiza-tion problem on a product of two complex Stiefel manifolds,a practical algorithm based on the generic Riemannian trust-region method of Absil et *** presented to solve the underlying problem,which enjoys the global convergence and local superlinear conver-gence *** experiments are provided to illustrate the efficiency of the proposed *** with some classical Riemannian gradient-type methods,the existing Riemannian version of limited-memory BFGS algorithms in the MATLAB toolbox Manopt and the Riemannian manifold optimization library ROPTLIB,and some latest infeasible methods for solving manifold optimization problems,are also provided to show the merits of the proposed approach.

关键词： Truncated singular value decomposition Riemannian optimization Trust-region method

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Core-shell nanoparticle enhanced Raman spectroscopy in situ probing the composition and evolution of interfacial species on PtCo surfaces

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Nano Research 2024年第6期17卷 4687-4692页

作者： Jing Liu Han-Liang Zhong Xiangyu Li Mu-Fei Yue Wei-Min Yang Xueqiu You Jing-Hua Tian Yao-Hui Wang Jian-Feng Li Fujian Provincial Key laboratory of Oceanic Information Perception and Intelligent Processing School of Ocean Information EngineeringJimei UniversityXiamen 361021China College of Chemistry Fuzhou UniversityFuzhou 350108China State Key laboratory of Physical Chemistry of Solid Surfaces MOE Key Laboratory of Spectrochemical Analysis and InstrumentationiChEMCollege of Chemistry and Chemical EngineeringCollege of MaterialsCollege of EnergyXiamen UniversityXiamen 361005China Innovation laboratory for Sciences and Technologies of Energy Materials of Fujian Province(IKKEM) Xiamen 361005China Shenzhen Research Institute of Xiamen University Shenzhen 518000China

The composition and evolution of interfacial species play a key role during electrocatalytic *** the structural evolution and intermediate during catalytic process by in situ characterization can shed new light on the electrocatalytic reaction mechanism and develop highly efficient ***,directly probing the interfacial species is extremely difficult for most spectroscopic techniques due to complicated interfacial environment and ultra-low surface ***,electrochemical core-shell nanoparticle enhanced Raman spectroscopy is utilized to probe the composition and evolution processes of interfacial species on Au@Pt,Au@Co,and Au@PtCo core-shell nanoparticle *** spectral evidences of interfacial intermediates including hydroxide radical(OH*),superoxide ion(O_(2)^(−)),as well as metal oxide species are directly captured by in situ Raman spectroscopy,which are further confirmed by the both isotopic experiment and density functional theory *** results provide a mechanistic guideline for the rational design of highly efficient electrocatalysts.

关键词： in situ Raman core-shell nanoparticle PtCo interfacial species composition and evolution

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Effects of phosphorus limitation on sinking velocities of phytoplankton during summer in the Changjiang River Estuary

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Acta Oceanologica Sinica 2024年第6期43卷 131-141页

作者： Xinchi You Qiang Hao Jie Zhu Wei Zhang Haiyan Jin Dewang Li Huanhong Ji Yu Ke Feng Zhou Ocean College Zhejiang UniversityZhoushan 316021China State Key laboratory of Satellite Ocean Environment Dynamics Second Institute of OceanographyMinistry of Natural ResourcesHangzhou 310000China Key laboratory of Marine Ecosystem Dynamics Second Institute of OceanographyMinistry of Natural ResourcesHangzhou 310012China Donghai laboratory Zhoushan 316021China East China Sea Ecological Center Ministry of Natural ResourcesShanghai 201206China Key laboratory of Marine Ecological Monitoring and Restoration Technologies Ministry of Natural ResourcesShanghai 201206China Observation and Research Station of Yangtze River Delta Marine ecosystems Ministry of Natural ResourcesZhoushan 316021China

The sinking of phytoplankton is critical to organic matter transportation in the ocean and it is an essential process for the formation of coastal hypoxic *** study was based on a field investigation conducted during the summer of 2022 in the Changjiang River(Yangtze River) Estuary(CJE) and its adjacent *** settling column method was employed to measure the sinking velocity(SV) of different size fractions of phytoplankton at the surface of the sea and to analyze their environmental control *** findings reveal significant spatial variation in phytoplankton SV(-0.55-2.41 m/d) within the ***-speed sinking was predominantly observed in phosphate-depleted regions beyond the CJE *** the same time,an upward trend was more commonly observed in the phosphate-rich regions near the CJE *** SV ranges for different sizefractionated phytoplankton,including micro-(>20 μm),nano-(2-20 μm),and picophytoplankton(0.7-2 μm),were-0.50-4.74 m/d,-1.04-1.59 m/d,and-1.24-1.65 m/d,*** analysis revealed a significant negative correlation between SV and dissolved inorganic phosphorus(DIP),implying that the influence of DIP contributes to *** variations in phytoplankton alkaline phosphatase activity suggested a significant increase in SV across all size fractions in the event of phosphorus *** communities with limited photo synthetic capacity(maximum photochemical efficience,Fv/Fm <0.3) were found to have higher SV than that of communities with strong capacity,suggesting a link between sinking and alterations in physiological conditions due to phosphate *** findings from the in situ phosphate enrichment experiments confirmed a marked decrease in SV following phosphate *** findings suggest that phosphorus limitation is the primary driver of elevated SV in the *** study enhances the comprehension of the potential mechanisms underlying hypoxic zone formation in the CJE,providing no

关键词： phytoplankton sinking velocity Changjiang River Estuary phosphorus limitation alkaline phosphatase

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