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Science China Chemistry 2023年第10期66卷 2863-2870页

作者： Yi-Kang xing Zhen-Hua Wang Ping Fang Cong ma Tian-sheng Mei State Key Laboratory of Organometallic Chemistry Shanghai Institute of Organic ChemistryUniversity of Chinese Academy of SciencesShanghai 200032China

Electrochemistry-enabled rhodium-catalyzed C–H amination and amination cyclization of arene assisted by a weakly coordinating amide have been reported. Additionally, aryl amines and dihydroquinazolinones could be obtained selectively by controlling the electric current. Mechanistic studies suggested that the amination reaction likely involves an electrochemical oxidation-induced reductive elimination of a high valent rhodium intermediate, which led to the amination reaction even proceeding smoothly at room temperature.

关键词： organic electrochemistry rhodium catalysis C-H functionalization divergent synthesis

Recent Advances in Fibrous materials for Hydroelectricity Generation

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Nano-Micro Letters 2025年第2期17卷 109-133页

作者： Can Ge Duo Xu Xiao Feng xing Yang Zheheng Song Yuhang Song Jingyu Chen Yingcun Liu Chong Gao Yong Du Zhe Sun Weilin Xu Jian Fang College of Textile and Clothing Engineering Soochow UniversitySuzhou 215123People’s Republic of China National Engineering Laboratory for Modern Silk Soochow UniversitySuzhou 215123People’s Republic of China State Key Laboratory of New Textile materials and Advanced Processing Technologies Wuhan Textile UniversityWuhan 430200People’s Republic of China Institute of Functional Nano&Soft materials(FUNSOM) Soochow UniversitySuzhou 215123People’s Republic of China Department of Electrical and Computer Engineering University of MassachusettsAmherstMA 01003USA Department of materials Imperial College LondonSouth Kensington CampusLondon SW72AZUK College of Textile Science and Engineering Zhejiang Sci-Tech UniversityHangzhou 310018People’s Republic of China School of materials Science and Engineering Shanghai Institute of Technology100 Haiquan RoadShanghai 201418People’s Republic of China

Depleting fossil energy sources and conventional polluting power generation pose a threat to sustainable *** generation from ubiquitous and spontaneous phase transitions between liquid and gaseous water has been considered a promising strategy for mitigating the energy *** materials with unique flexibility,processability,multifunctionality,and practicability have been widely applied for fibrous materials-based hydroelectricity generation(FHG).In this review,the power generation mechanisms,design principles,and electricity enhancement factors of FHG are first ***,the fabrication strategies and characteristics of varied constructions including 1D fiber,1D yarn,2D fabric,2D membrane,3D fibrous framework,and 3D fibrous gel are ***,the advanced functions of FHG during water harvesting,proton dissociation,ion separation,and charge accumulation processes are analyzed in ***,the potential applications including power supply,energy storage,electrical sensor,and information expression are also ***,some existing challenges are considered and prospects for future development are sincerely proposed.

关键词： Hydroelectricity Fibrous material Streaming potential Ion diffusion

FAAD:an unsupervised fast and accurate anomaly detection method for a multi-dimensional sequence over data stream

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Frontiers of Information Technology & Electronic Engineering 2019年第3期20卷 388-404页

作者： Bin LI Yi-jie WANG Dong-sheng YANG Yong-mou LI xing-kong ma Science and Technology on Parallel and Distributed Processing Laboratory College of ComputerNational University of Defense Technology Block Chain Research Institute of LianLian Pay

Recently, sequence anomaly detection has been widely used in many fields. Sequence data in these fields are usually multi-dimensional over the data stream. It is a challenge to design an anomaly detection method for a multi-dimensional sequence over the data stream to satisfy the requirements of accuracy and high speed. It is because:(1) Redundant dimensions in sequence data and large state space lead to a poor ability for sequence modeling;(2) Anomaly detection cannot adapt to the high-speed nature of the data stream, especially when concept drift occurs, and it will reduce the detection rate. On one hand, most existing methods of sequence anomaly detection focus on the single-dimension sequence. On the other hand, some studies concerning multi-dimensional sequence concentrate mainly on the static database rather than the data stream. To improve the performance of anomaly detection for a multi-dimensional sequence over the data stream, we propose a novel unsupervised fast and accurate anomaly detection(FAAD) method which includes three algorithms. First, a method called "information calculation and minimum spanning tree cluster" is adopted to reduce redundant dimensions. Second, to speed up model construction and ensure the detection rate for the sequence over the data stream, we propose a method called"random sampling and subsequence partitioning based on the index probabilistic suffix tree." Last, the method called "anomaly buffer based on model dynamic adjustment" dramatically reduces the effects of concept drift in the data stream. FAAD is implemented on the streaming platform Storm to detect multi-dimensional log audit *** with the existing anomaly detection methods, FAAD has a good performance in detection rate and speed without being affected by concept drift.

关键词： Data stream Multi-dimensional sequence Anomaly detection Concept drift Feature selection

Nitrogen–sulfur co-doped porous carbon derived from asphalt as efficient catalyst for oxygen reduction

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Rare Metals 2024年第1期43卷 380-388页

作者： Jing-sheng ma Ming-Zai Wu Ling Chen Li-xing Zhang Ying Xiong Key Laboratory of Structure and Functional Regulation of Hybrid materials Ministry of EducationInstitute of EnergyHefei Comprehensive National Science CenterAnhui UniversityHefei 230601China

As an environment-friendly and low-cost petrochemical by-product, asphalt has great potential in the preparation of metal-free oxygen reduction electrocatalysts with excellent performance and outstanding stability. In this paper, we converted asphalt into porous carbon nanosheets by a simple activation method, using potassium citrate as the swelling agent.

关键词： stability porous catalyst

Reliability and Numerical Analysis of a Robot Safety System

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Journal of Systems Science & Complexity 2019年第4期32卷 1072-1092页

作者： QIAO xing ma Dan College of Automation Harbin Engineering UniversityHarbin 150001China School of mathematical Science Daqing Normal UniversityDaqing 163712China

This paper discusses a model for a repairable robot safety system composed of a safety component and two redundant robots according to a semi-group *** development of the model is divided into three phases:(Ⅰ)The use of pure analysis to prove the uniqueness of a classical solution to the model;(Ⅱ)The verification of this uniqueness by providing a non-negative solution to the model;and(Ⅲ)the formulation of reliability indices for the model,along with numerical examples to explain the *** existence,uniqueness,and exponential stability of the solution of the repairable robot safety system is studied using Volterra-type integral-differential-equation theory,and the spectral distribution of the ACP operator is ***,the authors propose a method to investigate the steady-state indicator of the robot safety system with the safety component working,and with or without the component revolving,to make use of the correspondence of the eigenvector to the eigenvalue *** authors show that the robot’s operation,with or without the safety component revolving and with fractional motion,is superior to that with the safety component *** novelty of the approach lies in its examination of a unique solution to the system and its exponential stability based on C0-semi-group theory,the co-final relative theory,and the functional analysis method.

关键词： Numerical analysis reliability index robot safety system stability

Diagnostic performance of dynamic contrast-enhanced magnetic resonance imaging parameters and serum tumor markers in rectal carcinoma prognosis

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World Journal of Gastrointestinal Oncology 2024年第5期16卷 1796-1807页

作者： Ren-Qi Mu Jun-Wei Lv Cai-Yun ma Xiao-Hui ma Dong xing Hou-sheng ma Department of Radiology Yantai Mountain HospitalYantai 264001Shandong ProvinceChina Department of Radiology Yantai Yuhuangding HospitalYantai 264000Shandong ProvinceChina Department of Gynaecology Yantai Yuhuangding HospitalYantai 264000Shandong ProvinceChina The First Clinical Medical College Xinjiang Medical UniversityUrumqi 830011Xinjiang Uygur Autonomous RegionChina

BACKGROUND Rectal carcinoma(RC),one of the most common malignancies globally,presents an increasing incidence and mortality year by year,especially among young people,which seriously affects the prognosis and quality of life of *** present,dynamic contrast-enhanced magnetic resonance imaging(DCE-MRI)parameters and serum carbohydrate antigen 19-9(CA19-9)and CA125 Levels have been used in clinical practice to evaluate the T stage and differentiation of ***,the accuracy of these evaluation modalities still needs further *** study explores the application and value of these methods in evaluating the T stage and differentiation degree of *** To analyze the diagnostic performance of DCE-MRI parameters combined with serum tumor markers(TMs)in assessing pathological processes and prognosis of RC *** A retrospective analysis was performed on 104 RC patients treated at Yantai Yuhuangding Hospital from may 2018 to January *** were categorized into stages T1,T2,T3,and T4,depending on their T stage and differentiation *** addition,they were assigned to low(L group)and moderate-high differentiation(M+H group)groups based on their differentiation *** levels of DCE-MRI parameters and serum CA19-9 and CA125 in different groups of patients were *** addition,the value of DCE-MRI parameters[volume transfer constant(Ktrans),rate constant(Kep),and extravascular extracellular volume fraction(Ve)in assessing the differentiation and T staging of RC patients was ***,the usefulness of DCE-MRI parameters combined with serum CA19-9 and CA125 Levels in the evaluation of RC differentiation and T staging was *** Ktrans,Ve,CA19-9 and CA125 were higher in the high-stage group and L group than in the low-stage group and M+H Group,respectively(P<0.05).The areas under the curve(AUCs)of the Ktran and Ve parameters were 0.638 and 0.694 in the diagnosis of high and low stages,respectively,and 0.672 and 0

关键词： Rectal carcinoma Volume transfer constant Rate constant Extravascular extracellular volume fraction Serum carbohydrate antigen 19-9 Serum carbohydrate antigen 125

Domain Rotation Simulation of the magnetostriction Jump Effect of 〈110〉 Oriented TbDyFe Crystals

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Chinese Physics Letters 2012年第2期29卷 193-196页

作者： ZHANG Chang-sheng ma Tian-Yu PAN xing-Wen YAN Mi Department of materials Science and Engineering and State Key Laboratory of Silicon MaterialsZhejiang UniversityHangzhou 310027

The compressive pre-stress induced magnetostriction jump effect of an [(-1) 10] oriented TbDyFe crystal is simulated by tracking the initial redistribution of magnetic domains and their volune fraction evolutions under external magnetic *** searching for the free energy minima within both ((-1) 10) and (110) planes,it is found that the axial compressive pre-stress not only switches magnetizations of the 35° domains toward the perpendicular plane,but also switches magnetizations of the 90° domains approaching the [110] *** increasing the stress magnitude,the volume fraction for 35° domains decreases and the one for the [110] domain increases ***,the volume fraction for the four 90° domains within the perpendicular plane first increases to a maximum under a certain stress magnitude and further *** stress-induced anisotropy thereafter changes the volume fraction evolutions during the magnetization process,which explains well the magnetostriction jump effect.

关键词： stress magnetization TbDyFe

Automatic extraction and structuration of soil–environment relationship information from soil survey reports

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Journal of Integrative Agriculture 2019年第2期18卷 328-339页

作者： WANG De-sheng LIU Jun-zhi ZHU A-xing WANG Shu ZENG Can-ying ma Tianwu Key Laboratory of Virtual Geographic Environment Nanjing Normal UniversityNanjing 210023P.R.China State Key Laboratory Cultivation Base of Geographical Environment Evolution(Jiangsu Province) Nanjing 210023P.R.China Jiangsu Center for Collaborative Innovation in Geographic Information Resource Development and Application Nanjing 210023P.R.China State Key Laboratory of Resources and Environmental Information System Institute of Geographic Sciences and Natural Resources ResearchChinese Academy of SciencesBeijing 100101P.R.China Department of Geography University of Wisconsin-MadisonMadisonWI 53706USA

In addition to soil samples, conventional soil maps, and experienced soil surveyors, text about soils(e.g., soil survey reports) is an important potential data source for extracting soil–environment relationships. Considering that the words describing soil–environment relationships are often mixed with unrelated words, the first step is to extract the needed words and organize them in a structured way. This paper applies natural language processing(NLP) techniques to automatically extract and structure information from soil survey reports regarding soil–environment relationships. The method includes two steps:(1) construction of a knowledge frame and(2) information extraction using either a rule-based method or a statistic-based method for different types of information. For uniformly written text information, the rule-based approach was used to extract information. These types of variables include slope, elevation, accumulated temperature, annual mean temperature, annual precipitation, and frost-free period. For information contained in text written in diverse styles, the statistic-based method was adopted. These types of variables include landform and parent material. The soil species of China soil survey reports were selected as the experimental dataset. Precision(P), recall(R), and F1-measure(F1) were used to evaluate the performances of the method. For the rule-based method, the P values were 1, the R values were above 92%, and the F1 values were above 96% for all the involved variables. For the method based on the conditional random fields(CRFs), the P, R and F1 values for the parent material were, respectively, 84.15, 83.13, and 83.64%; the values for landform were 88.33, 76.81, and 82.17%, respectively. To explore the impact of text types on the performance of the CRFs-based method, CRFs models were trained and validated separately by the descriptive texts of soil types and typical profiles. For parent material, the maximum F1 value for the descriptive text

关键词： soil–environment relationship text natural language processing extraction structuration

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基于纸基微芯片的样本前处理方法研究进展

分析测试学报 2025年第1期44卷 91-98页

作者：马亚星顾梦杰李旭东沈先涛华中科技大学同济医学院公共卫生学院湖北武汉430030

纸基微芯片(μPADs)是一种以纸质材料为基底的简易、便携式检测平台,在临床诊断、食品质量控制和环境监测等领域显示出极大的应用前景。作为快速检测平台,纸基微芯片除了需要对目标物进行快速定量,还要完成样本的前处理过程。科学家近... 详细信息

纸基微芯片(μPADs)是一种以纸质材料为基底的简易、便携式检测平台,在临床诊断、食品质量控制和环境监测等领域显示出极大的应用前景。作为快速检测平台,纸基微芯片除了需要对目标物进行快速定量,还要完成样本的前处理过程。科学家近年来开发了多种基于纸基微芯片的样本前处理方法,用于不同样本中目标物的分析。由于纸基具有强兼容性能,增强纸基芯片的样本前处理功能并将其与各种快速检测方法联用,能极大地扩展纸基微芯片的应用领域。该文对纸基微芯片的自驱动以及纸基微芯片自驱动与外驱动相结合的样本前处理方法进行了总结,概述了纸基微芯片在目标分析物提取、富集等前处理方面的研究进展,探讨了各种纸基微芯片前处理方法的优点和局限性。另外还展望了纸基微芯片的发展方向—除了不断提高样品前处理能力来扩展其在样本制备中的应用,还需要开发商业化的纸基微芯片来满足各类行业的检测需求。

关键词：快速分析纸基微芯片分离驱动前处理

The effect of cation–π interactions in electrolyte/organic nanofiltration systems

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Chinese Journal of Chemical Engineering 2016年第3期24卷 345-352页

作者： Gang Yang Yu ma Weihong xing Nanjing Tech University Nanjing 210009China

The rejection properties of a nanofiltration organic membrane were investigated using KCI solutions, NaC1 solutions, NaC1/benzyl alcohol hybrid solutions and KCl/benzyl alcohol hybrid solutions. The presence of benzyl alcohol （3.7 mol · m-3） caused a decrease in electrolyte rejection within the range of 0 to 6%. The mechanism of the decrease was discussed. The cation-n bond was assumed to form in the hybrid solution and to further induce the partial dehydration of the cation. The steric and charge density inhibition of the salt activity was strengthened, and the salt rejection was thus decreased. A simulation was performed to evaluate the radius of the cation. 2015 The Chemical Industry and Engineering Society of China, and Chemical Industry Press. All rights reserved.

关键词： Nanofiltration Cation-n interaction Dehydration Steric effect