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Chinese Chemical Letters 2015年第7期26卷 829-833页

作者： di Zhao Yong chen yu Liu Department of Chemistry State Key Laboratory of Elemento-Organic Chemistry Nankai University Collaborative Innovation Center of Chemical Science and Engineering (Tianjin)

A β cyclodextrin derivative bearing seven cationic arms and its singly charged analogue, i.e., per-6- deoxy-f-（1-methylimidazol-3-ium-3-yl）-β-cyclodextrin （3） and mono-fi-deoxy-6-（1-methylimidazol- 3-ium-3-yl）-β-cyclodextrin （4） were synthesized and fully characterized. Their induced aggregation behaviours towards two anionic surfactant, that is, sodium dodecyl sulfonate （SDS） and dioctyl sodium sulfosuccinate （Aerosol OT, AOT）, were investigated by UV-vis, NMR, Zeta-potential, dynamic light scattering （DLS）, and transmission electron microscopy. The results revealed that host 3 can induce the molecular aggregation of anionic surfactant at concentration far lower than its original CAC, leading to the larger diameter, the narrower size distribution and the higher thermal stability of the induced aggregate towards the anionic surfactant possessing more hydrophobic tails.

关键词： Cyclodextrin Surfactant Molecular assembly Induced aggregation

Enhancing stability of diradical polycyclic hydrocarbons via P=O-attaching

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Chinese Chemical Letters 2024年第8期35卷 309-313页

作者： Jingyuan Yang Xinyu Tian Liuzhong yuan yu Liu yue Wang Chuandong Dou State Key Laboratory of Supramolecular Structure and Materials College of ChemistryJilin UniversityChangchun 130012China Jiangsu Engineering Laboratory of Novel Functional Polymeric Materials Soochow UniversitySuzhou 215123China

diradical polycyclic hydrocarbons(PHs)have unique open-shell structures and interesting physical ***,owing to high reactivity of unpaired electrons,such open-shell organic diradicaloids are usually less stable than closed-shell systems,limiting their practical *** this study,we report P=O-attaching of diradical PHs as a new strategy to enhance their stability while maintaining diradi-cal *** P=O-attached PHs containing the indeno[1,2-b]fluorene,fluoreno[3,2-b]fluorene and indeno[2,1-b]fluoreneπ-skeletons,respectively,were designed and *** theoretically and ex-perimentally proved,two of them have the relatively large diradical characters and open-shell singlet diradical *** comparison to their all-carbon analogues,the attached electron-withdrawing P=O groups endow them with much lower LUMO/HOMO energy levels but preserved magnetic activities and physical properties,such as thermally accessible triplet species and multi-redox ***,the P=O groups effectively decrease their oxidation activities and thereby lead to their remarkably excellent ambient ***,this P=O-attaching strategy will be applicable to other diradical PH systems and may promote the generation of stable organic diradicaloids for radical chemistry and materials.

关键词： Polycyclic hydrocarbons Open-shell structure diradical character Stability Oxidation activity

SF_(6)混合气体放电的极性反转特性研究

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高压电器 2024年第7期60卷 114-121页

作者：陈远东郑宇国网内蒙古东部电力有限公司超特高压分公司内蒙古通辽028000 武汉大学电气与自动化学院武汉430072

SF_(6)混合气体可在极寒条件下替代SF_(6)气体用于气体绝缘电气设备,当设备中存在缺陷时会显著降低击穿电压,因此有必要研究缺陷产生的极不均匀电场中SF_(6)混合气体的放电特性。开展了针板电极下SF_(6)/CF_(4)、SF_(6)/N_(2)混合气体... 详细信息

SF_(6)混合气体可在极寒条件下替代SF_(6)气体用于气体绝缘电气设备,当设备中存在缺陷时会显著降低击穿电压,因此有必要研究缺陷产生的极不均匀电场中SF_(6)混合气体的放电特性。开展了针板电极下SF_(6)/CF_(4)、SF_(6)/N_(2)混合气体的放电试验,并和SF_(6)气体对比,分析其击穿电压随气压增大呈现的驼峰曲线变化规律。发现SF_(6)混合气体的驼峰曲线相比SF_(6)气体会发生右移,且SF_(6)/N_(2)混合气体的右移现象更加明显。进一步对比研究了不同气压下SF_(6)混合气体的击穿与局放特性,发现SF_(6)/CF_(4)、SF_(6)/N_(2)混合气体的击穿电压均随气压升高出现极性反转,即从负极性击穿转化为正极性击穿,极性反转对应的气压即为驼峰曲线峰谷处的气压;同时,局放特性也会随气压升高出现变化,即从正负极性局放共存转化为只存在正极性局放。通过分析SF_(6)混合气体的局放起始电压随气压的变化趋势,发现当高于峰谷气压时,局放起始电压与击穿电压相差较小,这一现象说明SF_(6)混合气体设备在较高气压时也更易出现无晕击穿,与SF_(6)气体设备的运维经验一致。研究结果对于SF_(6)混合气体设备的运维检修和设计具有参考意义。

关键词： SF_(6)混合气体气体绝缘气体放电无晕击穿驼峰曲线

Optimization of spatial layouts for underground facilities to achieve carbon neutrality in cities:A multi-agent system model

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Underground Space 2024年第6期19卷 251-278页

作者： Lingxiang Wei Dongjun Guo Junyuan Ji Zhilong chen Huapeng Hu Xiaoli Peng Research Center for Underground Space Army Engineering University of PLANanjing 210007China School of Materials Science and Engineering Yancheng Institute of TechnologyYancheng 224051China

Subways,underground logistics systems and underground parking,as the primary facilities types of underground,contribute significantly to the achievement of carbon–neutral cities by moving surface transportation to underground,thereby releasing surface space for the creation of more urban blue-green space for carbon ***,in-depth studies on carbon neutrality strategies as well as reliable layout optimization solutions of these three types of underground facilities are *** study proposes a spatial layout optimization strategy for carbon neutrality using underground hydrogen storage and geothermal energy for these three types of underground facilities employing a multi-agent system ***,three spatial layout relationships,competition,coordination,and followership,between five underground facilities that contribute to emission reduction were ***,the implementation steps for optimizing the spatial layout of underground facilities were determined by defining the behavioral guidelines for spatial environment,underground facility,and synergistic ***,using the Tianfu New district in chengdu City,China,as a case study,layouts of underground facilities under three different underground space development scenarios were simulated to verify the *** findings of this study address the gap in the research on underground spatial facilities and their layout optimization in response to emission *** study provided a significant reference for the study of underground space and underground resources at the planning level to aid in achieving carbon–neutral cities.

关键词： Urban underground space(UUS) Carbon-neutral city Multi-agent system model Underground facility Spatial layouts

Finite difference-Peridynamic differential Operator for Solving Transient Heat Conduction Problems

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Computer Modeling in Engineering & Sciences 2024年第9期140卷 2707-2728页

作者： Chunlei Ruan Cengceng Dong Zeyue Zhang Boyu chen Zhijun Liu School of Mathematics&Statistics Henan University of Science&TechnologyLuoyang471023China Longmen Laboratory Luoyang471023China

Transient heat conduction problems widely exist in *** previous work on the peridynamic differential operator(PDDO)method for solving such problems,both time and spatial derivatives were discretized using the PDDO method,resulting in increased complexity and programming *** this work,the forward difference formula,the backward difference formula,and the centered difference formula are used to discretize the time derivative,while the PDDO method is used to discretize the spatial *** new schemes for solving transient heat conduction equations have been developed,namely,the forward-in-time and PDDO in space(FT-PDDO)scheme,the backward-in-time and PDDO in space(BT-PDDO)scheme,and the central-in-time and PDDO in space(CT-PDDO)*** stability and convergence of these schemes are analyzed using the Fourier method and Taylor’s *** show that the FT-PDDO scheme is conditionally stable,whereas the BT-PDDO and CT-PDDO schemes are unconditionally *** stability conditions for the FT-PDDO scheme are less stringent than those of the explicit finite element method and explicit finite difference *** convergence rate in space for these three methods is *** constructed schemes are applied to solve one-dimensional and two-dimensional transient heat conduction *** accuracy and validity of the schemes are verified by comparison with analytical solutions.

关键词： Peridynamic differential operator finite difference method stability transient heat conduction problem

不同环境温度条件酿制的传统黄酒的滋味特征差异分析

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中国食品学报 2024年第4期24卷 361-369页

作者：于海燕吴世琪王晓雨陈臣田怀香上海应用技术大学香料香精化妆品学部上海201418

传统黄酒是中华酿造技艺之瑰宝,而其半开放的酿造环境易受环境温度条件等影响而导致产品风味品质不稳定。本研究以不同环境温度条件酿制的传统黄酒为研究对象(前性酒(S1)、中性酒(S2和S3)、后性酒(S4)),采用定量描述感官评价分析4批次... 详细信息

传统黄酒是中华酿造技艺之瑰宝,而其半开放的酿造环境易受环境温度条件等影响而导致产品风味品质不稳定。本研究以不同环境温度条件酿制的传统黄酒为研究对象(前性酒(S1)、中性酒(S2和S3)、后性酒(S4)),采用定量描述感官评价分析4批次传统黄酒的静态滋味强度差异,采用时间-强度感官评价和动态主导属性测试分析饮用过程中滋味特征的动态变化及不同批次间的差异,采用电子舌技术分析味觉风味轮廓差异,并结合偏最小二乘法建立滋味预测模型。结果表明:S2和S3的滋味和谐饱满,鲜味突出,苦味和后苦味强度弱;4批次传统黄酒的主导滋味属性按时间先、后均为酸味、苦味和鲜味,S3的苦味优势属性结束最早(85 s),S4的苦味消逝时间最久(110 s),S3的鲜味占据主导优势的时间最早,其次为S2、S1和S4。电子舌响应信号与酸、苦和后苦味感官评分具有较好的相关性,后苦味模型最稳健,模型的相关系数r为0.976。静态和动态感官评价结合电子舌可全面评价传统黄酒滋味特征差异,环境温度条件对传统黄酒苦味及后苦味具有重要影响。

关键词：传统黄酒滋味特征环境温度条件感官评价电子舌

A Spectral Convolutional Neural Network Model Based on Adaptive Fick’s Law for Hyperspectral Image Classification

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Computers, Materials & Continua 2024年第4期79卷 19-46页

作者： Tsu-Yang Wu Haonan Li Saru Kumari Chien-Ming chen School of Artificial Intelligence(School of Future Technology) Nanjing University of Information Science&TechnologyNanjing210044China College of Computer Science and Engineering Shandong University of Science and TechnologyQingdao266590China Department of Mathematics Chaudhary Charan Singh UniversityMeerutUttar Pradesh250004India

Hyperspectral image classification stands as a pivotal task within the field of remote sensing,yet achieving highprecision classification remains a significant *** response to this challenge,a Spectral Convolutional Neural Network model based on Adaptive Fick’s Law Algorithm(AFLA-SCNN)is *** Adaptive Fick’s Law Algorithm(AFLA)constitutes a novel metaheuristic algorithm introduced herein,encompassing three new strategies:Adaptive weight factor,Gaussian mutation,and probability update *** adaptive weight factor,the algorithmcan adjust theweights according to the change in the number of iterations to improve the performance of the *** helps the algorithm avoid falling into local optimal solutions and improves the searchability of the *** probability update strategy helps to improve the exploitability and adaptability of the *** the AFLA-SCNN model,AFLA is employed to optimize two hyperparameters in the SCNN model,namely,“numEpochs”and“miniBatchSize”,to attain their optimal ***’s performance is initially validated across 28 functions in 10D,30D,and 50D for CEC2013 and 29 functions in 10D,30D,and 50D for *** results indicate AFLA’s marked performance superiority over nine other prominent optimization ***,the AFLA-SCNN model was compared with the Spectral Convolutional Neural Network model based on Fick’s Law Algorithm(FLA-SCNN),Spectral Convolutional Neural Network model based on Harris Hawks Optimization(HHO-SCNN),Spectral Convolutional Neural Network model based ondifferential Evolution(DE-SCNN),SpectralConvolutionalNeuralNetwork(SCNN)model,and SupportVector Machines(SVM)model using the Indian Pines dataset and PaviaUniversity *** experimental results show that the AFLA-SCNN model outperforms other models in terms of Accuracy,Precision,Recall,and F1-score on Indian Pines and Pavia *** them,the Accuracy of the AFLA-SCNN model on India

关键词： Adaptive Fick’s law algorithm spectral convolutional neural network metaheuristic algorithm intelligent optimization algorithm hyperspectral image classification

Coordinated Restoration Method for Electric Buses and Network Reconfigurations in distribution Systems Under Extreme Events

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CSEE Journal of Power and Energy Systems 2024年第5期10卷 1994-2003页

作者： Bo Zhang Lu Zhang Wei Tang Zhaoqi Wang chen Wang China Agricultural University Beijing 100083China State Grid Energy Research Institute Co.Ltd Beijing 102209China State Grid Beijing Electric Power Research Institute Beijing 100075China

distribution systems are facing challenges in serving lifeline loads after extreme *** reconfiguration is a traditional and practical method for power supply restoration,which has strong but inflexible power transfer capabilities influenced by network *** failures of utility power under extreme events will further limit the efficiency of network *** buses(EBs)can be utilized to achieve power supply considering their discharging capabilities as mobile storage ***,the mobility of EBs and the influences of transport systems must be carefully considered to enhance the resilience of distribution *** and EBs are complementary in terms of recovery capabilities and location flexibility,and more important loads can be recovered by the coordination between EBs and network *** paper proposes a coordinated restoration method for EBs and reconfigurations considering the influences of transport *** post-disaster restoration problem is formulated as a bi-level model,in which the network topology is optimized in the upperlevel aiming at maximizing restoration loads through the main grid and EBs,while the traffic paths of all EBs are optimized with the goal of maximizing the restoration loads by the EBs in the lower-level considering time consumption and energy consumption during *** PSO and a genetic algorithm are used to solve the proposed bi-level optimization *** studies are performed to verify the superiority of the proposed method.

关键词： distribution system electric bus extreme event network reconfiguration restoration transport system

discovery and intensity characterization of TDP and PRP based on temperature evolution history during the pyrolysis for large biomass particle

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Carbon Resources Conversion 2024年第3期7卷 41-50页

作者： Rui chen Jun Cai Xinli Li Xiaobin Qi State Key Laboratory of Coal Conversion Institute of Engineering ThermophysicsChinese Academy of SciencesBeijing 100190China University of Chinese Academy of Sciences No.19 Yuquan RoadShijingshan DistrictBeijing 100049China Shanxi Engineering Research Center of Coal Clean Efficient Combustion and GasificationNo.1619 Yunzhou StreetDatong CityShanxi Province 037305China Shanxi Key Laboratory of Coal Flexible Combustion and Thermal Conversion No.1619 Yunzhou StreetDatong CityShanxi Province 037305China

The pyrolysis behaviors and temperature evolution history of lignocellulosic biomass(Beech,BH)were characterized using a novel pyrolysis *** simulation results were validated through corresponding experimental *** on the simulation results,two distinct peaks were observed in the temperature difference between the surface and center(TDSC)curve,namely the thermal disturbance peak(TDP)and the pyrolysis reaction peak(PRP).The presence of TDP and PRP was confirmed by examining the heat flux ratio between the pyrolysis rate and the temperature rise ***,the results indicated that three factors,namely heating temperature,particle size,and pyrolysis rate,influenced the relative intensity between TDP and *** changing the values of each impact factor,conditions where TDP owns the same height with PRP were obtained under different working *** findings have led to the development of a dimensionless number,naming the pyrolysis-heating surface-center number(PHSC number).This number could provide a comprehensive indication of the collective impact of the aforementioned factors when TDP and PRP exhibit equal peak heights.

关键词： DAEM Large biomass particle Pyrolysis Temperature distribution dimensionless number

Prediction Model of Wax Deposition Rate in Waxy Crude Oil Pipelines by Elman Neural Network Based on Improved Reptile Search Algorithm

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Energy Engineering 2024年第4期121卷 1007-1026页

作者： Zhuo chen Ningning Wang Wenbo Jin Dui Li The Second Oil Production Plant Sinopec Northwest Oilfield CompanyUrumqi830011China Yingmaili Oil and Gas Production Management Area PetroChina Tarim Oilfield CompanyKorla841001China College of Petroleum Engineering Xi’an Shiyou UniversityXi’an710065China

A hard problem that hinders the movement of waxy crude oil is wax deposition in oil *** ensure the safe operation of crude oil pipelines,an accurate model must be developed to predict the rate of wax deposition in crude oil *** at the shortcomings of the ENN prediction model,which easily falls into the local minimum value and weak generalization ability in the implementation process,an optimized ENN prediction model based on the IRSA is *** validity of the new model was confirmed by the accurate prediction of two sets of experimental data on wax deposition in crude oil *** two groups of crude oil wax deposition rate case prediction results showed that the average absolute percentage errors of IRSA-ENN prediction models is 0.5476% and 0.7831%,***,it shows a higher prediction accuracy compared to the ENN prediction *** fact,the new model established by using the IRSA to optimize ENN can optimize the initial weights and thresholds in the prediction process,which can overcome the shortcomings of the ENN prediction model,such as weak generalization ability and tendency to fall into the local minimum value,so that it has the advantages of strong implementation and high prediction accuracy.

关键词： Waxy crude oil wax deposition rate chaotic map improved reptile search algorithm Elman neural network prediction accuracy