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Kinetics and Mechanism of Exothermic First-stage Decomposition Reaction for 2,6-Dinitro-4,8- bis(2,2,2-trinitroethyl)-2,4,6,8-tetra- azabicyclo[3.3.1] nonane-3,7-dionel

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Chemical Research in Chinese Universities 2004年第5期20卷 821-825页

作者： HUrong-zu YANGDe-suo ZHAOFeng-qi CHENPei LUOYang CHENSan-ping ZHAOHong-an songji-rong GAOSheng-li SHIQi-zhen Xi′anModernChemistryResearchInstitute Xi′an710065P.R.China DepartmentofChemistryandChemicalEngineering BaojiCollegeofArtsandScienceBaoji721007P.R.China ShaanxiKeyLaboratoryofPhysico-InorganicChemistry DepartmentofChemistryNorthwestUniversityXi＇an710069P.R.China CollegeofChemicalEngineering NorthwestUniversityXi＇an710069P.R.China

2,6-Dinitro-4,8-bis(2,2,2-trinitroethyl)-2,4,6,8-tetraazabicyclo[3.3.1] nonane-3,7-dionel is a typical cyclourea nitramine. Its crystal density is 1.94 g/cm3. The detonation velocity corresponding to ρ=1.920 g/cm3 is about 8957 m/s. It has the potential application as high explosive due to the above-mentioned high performance. Its preparation[1], properties[1] and hydrolytic behavior[2] have been reported. In the present paper, we report its kinetic parameters and mechanism of the exothermic first-stage decomposition reaction studied with DSC, TG-DTG and IR.……

关键词： Decomposition 2,6-Dinitro-4,8- bis(2,2,2 -trinitroethyl)-2,4,6,8-tetraazabicyclo [3.3.1] nonane-3,7-dionel DSC Kinetics Mechanism TG

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Estimation of Critical Rate of Temperature Rise for Thermal Explosion of First Order Autocatalytic Decomposition Reaction Systems by Using Non-isothermal DSC

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Chemical Research in Chinese Universities 2004年第2期20卷 163-165页

作者： GUOPeng-jiang HUrong-zu ZHANGHai XIAZhi-ming songji-rong GAOSheng-li NINGBin-ke SHIQi-zhen LIUrong LUGui-e JIANGJi-you SchoolofChemistryandChemicalEngineering SouthwesternNormalUniversityChongqing400715P.R.China ShaanxiKeyLaboratoryofPhysico-InorganicChemistryandDepartmentofChemistry Xi''anModernChemistryResearchInstitute Xi''an710065P.R.China DepartmentofMathematics NorthwestUniversityXi''an710069P.R.China DepartmentofFoodEngineering NanchangUniversityNanchang330047P.R.China OrdnanceEngineeringInstitute Shijiazhuang050000P.R.China

A method of estimating the critical rate of temperature rise for the thermal explosion of first order autocatalytic decomposition reaction systems by using non-isothermal DSC is presented. The information was obtained on the increasing rate of temperature for the first order autocatalytic decomposition of nitrocellulose containing 13.86% nitrogen converting into the thermal explosion.

关键词： DSC Critical rate of temperature rise NC Non-isothermal change Thermal explosion

The Thermal Decomposition Mechanism and the Quantum Chemical Calculation of[Mg（H2O）6]（NTO）2·2H2O

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含能材料 2004年第3期12卷 158-160,164,M004页

作者： MAHai-xia songji-rong XUKang-zhen HUrong-zu WENZhen-yi CollegeofChemicalEngineering／ShaanxiKeyLaboratoryofPhysico-InorganicChemistry NorthwestUniversity，Xi′an710069China ModernPhysicsInstitute．NorthwestUniversity，Xi′an，710069，China

[Mg(H2O)6](NTO)2·2H2O Was prepared by adding magnesium carbonate hydroxide to the aqueous solution of 3-nitro-1，2，4-triazol-5-one(NTO)．Its thermal decomposition mechanism was studied by DSC，TG／DTGand *** quantum chemical calculation on the title complex as a structure unit with the experimental geometry as atartmg values was carried out at B3LYP level with 6-31G basis *** results show that the bonds between the coordinate waters and the Mgatom have certain extent covalent *** net charges on nitrogen atoms of the NTO ring appear to be negative while the nitrogen atom on the nitro group(—NO2)appears to be positive which indicates—NO2 will lost first when the complex is heated to some uniform temperature and this result is in agreement with that of the thermal decomposition experiment．

关键词： physical chemistry 3-nitro-1,2.4-triazol-5-one(NTO) magnesium complex thermal decomposition mechanism quantum chemical investigation

PD-YOLO:Colon Polyp Detection Model Based on Enhanced Small-Target Feature Extraction

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Computers, Materials & Continua 2025年第1期82卷 913-928页

作者： Yicong Yu Kaixin Lin Jiajun Hong rong-Guei Tsai Yuanzhi Huang New Engineering Industry College Putian UniversityPutian351100China Engineering Research Center of Big Data Application in Private Health Medicine(Putian University) Fujian Province UniversityPutian351100China Computer College Guangdong University of Science&TechnologyDongguan523668China

In recent years,the number of patientswith colon disease has increased *** polyps are the precursor lesions of colon *** not diagnosed in time,they can easily develop into colon cancer,posing a serious threat to patients’lives and health.A colonoscopy is an important means of detecting colon ***,in polyp imaging,due to the large differences and diverse types of polyps in size,shape,color,etc.,traditional detection methods face the problem of high false positive rates,which creates problems for doctors during the diagnosis *** order to improve the accuracy and efficiency of colon polyp detection,this question proposes a network model suitable for colon polyp detection(PD-YOLO).This method introduces the self-attention mechanism CBAM(Convolutional Block Attention Module)in the backbone layer based on YOLOv7,allowing themodel to adaptively focus on key information and ignore the unimportant *** help themodel do a better job of polyp localization and bounding box regression,add the SPD-Conv(Symmetric Positive Definite Convolution)module to the neck layer and use deconvolution instead of *** results indicate that the PD-YOLO algorithm demonstrates strong robustness in colon polyp *** to the original YOLOv7,on the Kvasir-SEG dataset,PD-YOLO has shown an increase of 5.44 percentage points in AP@0.5,showcasing significant advantages over other mainstream methods.

关键词： Polyp detection YOLOv7 SPD-Conv CBAM deconvolution

High-throughput screening of CO_(2) cycloaddition MOF catalyst with an explainable machine learning model

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Green Energy & Environment 2025年第1期10卷 132-138页

作者： Xuefeng Bai Yi Li Yabo Xie Qiancheng Chen Xin Zhang Jian-rong Li Beijing Key Laboratory for Green Catalysis and Separation and Department of Chemical Engineering College of Materials Science&EngineeringBeijing University of TechnologyBeijing100124China

The high porosity and tunable chemical functionality of metal-organic frameworks(MOFs)make it a promising catalyst design ***-throughput screening of catalytic performance is feasible since the large MOF structure database is *** this study,we report a machine learning model for high-throughput screening of MOF catalysts for the CO_(2) cycloaddition *** descriptors for model training were judiciously chosen according to the reaction mechanism,which leads to high accuracy up to 97%for the 75%quantile of the training set as the classification *** feature contribution was further evaluated with SHAP and PDP analysis to provide a certain physical understanding.12,415 hypothetical MOF structures and 100 reported MOFs were evaluated under 100℃ and 1 bar within one day using the model,and 239 potentially efficient catalysts were *** them,MOF-76(Y)achieved the top performance experimentally among reported MOFs,in good agreement with the prediction.

关键词： Metal-organic frameworks High-throughput screening Machine learning Explainable model CO_(2)cycloaddition

Enantioselective reductive conjugate alkenylation of α,β-enones with keto alkenyl acetates by nickel catalysis

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Science China Chemistry 2025年第1期68卷 157-162页

作者： rong-De He Yun-Lei Luo Qiu-Quan Pan Qi-Wei Yao Xing-Zhong Shu State Key Laboratory of Applied Organic Chemistry College of Chemistry and Chemical Engineering Lanzhou University

Reactions involving alkenyl acetates offer cost-effective and environmentally friendly routes for alkene synthesis, yet their asymmetric variant remains elusive. Concurrently, asymmetric conjugate alkenylation predominantly centered on nucleophilic addition using alkenyl–M. This manuscript presents an asymmetric reductive conjugate alkenylation reaction involving alkenyl acetates. The method facilitates the enantioselective addition of keto alkenyl groups to α,β-enones, resulting in the formation of unsaturated diketones—a class of useful structural motifs that are challenging to access otherwise. The use of electron-rich Pyroxy ligand is essential for achieving both high reaction efficiency and enantioselectivity.

关键词： nickel alkenylation asymmetric cross-coupling alkenes

Recent Advances in Artificial Sensory Neurons:Biological Fundamentals,Devices,Applications,and Challenges

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Nano-Micro Letters 2025年第3期17卷 168-216页

作者： Shuai Zhong Lirou Su Mingkun Xu Desmond Loke Bin Yu Yishu Zhang rong Zhao Guangdong Institute of Intelligence Science and Technology HengqinZhuhai 519031People’s Republic of China College of Integrated Circuits Zhejiang UniversityHangzhou 3112000People’s Republic of China ZJU-Hangzhou Global Scientific and Technological Innovation Center Hangzhou 310027People’s Republic of China Department of Science Mathematics and TechnologySingapore University of Technology and DesignSingapore 487372Singapore Department of Precision Instruments Tsinghua UniversityBeijing 100084People’s Republic of China Center for Brain‑Inspired Computing Research Tsinghua UniversityBeijing 100084People’s Republic of China IDG/McGovern Institute for Brain Research Tsinghua UniversityBeijing 100084People’s Republic of China

Spike-based neural networks,which use spikes or action potentialsto represent information,have gained a lot of attention because of their high energyefficiency and low power *** fully leverage its advantages,convertingthe external analog signals to spikes is an essential *** including analog-to-digital converters or ring oscillators,and sensorssuffer from high power and area *** efforts are devoted to constructingartificial sensory neurons based on emerging devices inspired by the biologicalsensory *** can simultaneously perform sensing and spike conversion,overcoming the deficiencies of traditional sensory *** review summarizesand benchmarks the recent progress of artificial sensory *** starts with thepresentation of various mechanisms of biological signal transduction,followed bythe systematic introduction of the emerging devices employed for artificial ***,the implementations with different perceptual capabilitiesare briefly outlined and the key metrics and potential applications are also ***,we highlight the challenges and perspectives for the future development of artificial sensory neurons.

关键词： Artificial intelligence Emerging devices Artificial sensory neurons Spiking neural networks Neuromorphic sensing

Direct and rapid detection of serum amino acid and monoamine neurotransmitters to assist the diagnosis of panic disorder

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Science China Chemistry 2025年第1期68卷 377-384页

作者： Shiwen Liu Xuerui Wan Meng Zhao Jiaqi Wang Weilan Wu Linlin You Yonggui Yuan Qian Xu rong Gao Key Laboratory of Environmental Medicine Engineering Ministry of Education School of Public Health Southeast University Key Laboratory of Modern Toxicology of Ministry of Education Department of Hygienic Analysis and Detection School of Public HealthNanjing Medical University Department of Psychosomatics and Psychiatry Zhongda Hospital School of Medicine Southeast University

The measurement of amino acid and monoamine neurotransmitters（NTs） in serum plays a central role in the identification and monitoring of clinical panic disorder（PD）. However, the strong polarity and chemical heterogeneity of NTs make direct extraction and rapid detection extremely challenging. Herein, we developed a strategy that integrated solid phase extraction based on magnetic Fe3O4coated with polydopamine（Fe3O4@PDA） and direct analysis of mass spectrometry in real time（DART-MS） for quantification of 10 NTs. We systematically investigated the optimal conditions of this strategy to achieve good accuracy and precision. Compared with existing magnetic solid phase extraction methods for NTs detection in biological samples, this strategy could adsorb more targets while having similar adsorption efficiencies, and the total process time was reduced by an average of 69.42%. We rapidly determined the metabolic abnormality of 6 types of NTs in the serum of PD patients and demonstrated their diagnostic accuracy. In addition, an outstanding feature of PD in which tryptophan was more metabolized by the KYN pathway and the 5-hydroxytryptamine pathway was inhibited could be elucidated by this strategy. Our results highlighted the potential ability of Fe3O4@PDA coupled with DART-MS to assist in the clinical diagnosis of PD.

关键词： neurotransmitters panic disorder magnetic solid phase extraction direct analysis of mass spectrometry in real time

Federated local causal structure learning

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Science China(Information Sciences) 2025年

作者： Kui YU Chen rong Hao WANG Fuyuan CAO Jiye LIANG School of Computer and Information Hefei University of Technology School of Computer and Information Technology Shanxi University

Local causal structure learning (LCS) efficiently identifies a set of direct neighbors of a specified variable from observational data. Additionally, it distinguishes direct causes and direct effects of this variable without learning the entire causal structure. While many LCS algorithms have been proposed, they do not consider the data privacy-preserving problem,which has attracted extensive attention from academia and industry. To address this issue, we propose a federated local causal structure learning (FedLCS) algorithm to learn local causal structures in privacy-preserving data in a federated ***, FedLCS introduces a layer-wise federated local skeleton learning algorithm to construct the local skeleton. Based on this skeleton, it introduces a federated local skeleton orientation algorithm and an extension-and-backtracking orientation algorithm to orient the edges. Finally, FedLCS uses a federated local extension-and-backtracking orientation algorithm to orient the remaining edges. Extensive experiments on benchmark, synthetic, and real datasets demonstrate that FedLCS can learn the local causal structure of a given variable in a federated setting.

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