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Computational insights into different regioselectivities in the Ir-porphyrin-catalyzed C–H insertion reaction of quinoid carbene

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Organic Chemistry Frontiers 2022年第4期9卷 1143-1151页

作者： Xiahe Chen Chaoqin Cao Yun-Fang Yang yuan-bin She College of Chemical Engineering Zhejiang University of TechnologyHangzhouZhejiang 310014China

The mechanisms and regioselectivities of the Ir-porphyrin-catalyzed C–H insertion reaction of quinoid carbene(QC)were investigated by density functional theory(DFT)*** competing catalytic cycles were identified as the hydrogen-atom abstraction by quinoid oxygen(HAA-O)and hydrogen-atom abstraction by carbene carbon(HAA-C)catalytic cycles.

关键词： porphyrin insertion catalyzed

A semi-analytical rate-transient analysis model for light oil reservoirs exhibiting reservoir heterogeneity and multiphase flow

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Petroleum Science 2023年第1期20卷 309-321页

作者： Jin-Chang Li bin yuan Christopher R.Clarkson Jian-Quan Tian Key Laboratory of Unconventional Oil&Gas Development(China University of Petroleum(East China)) Ministry of EducationQingdao266580ShandongPR China School of Petroleum Engineering China University of Petroleum(East China)Qingdao266580ShandongPR China Department of Geoscience University of CalgaryABT2L2N5Canada

Rate-transient analysis(RTA)has been widely applied to extract estimates of reservoir/hydraulic fracture ***,the majority of RTA techniques can lead to misdiagnosis of reservoir/fracture information when the reservoir exhibits reservoir heterogeneity and multiphase flow *** work proposes a practical-yet-rigorous method to decouple the effects of reservoir heterogeneity and multiphase flow during TLF,and improve the evaluation of reservoir/fracture properties.A new,general,semi-analytical model is proposed that explicitly accounts for multiphase flow,fractalbased reservoir heterogeneity,anomalous diffusion,and pressure-dependent fluid *** is achieved by introducing a new Boltzmann-type transformation,the exponent of which includes reservoir heterogeneity and anomalous *** order to decouple the effects of reservoir heterogeneity and multiphase flow during TLF,the modified Boltzmann variable allows the conversion of three partial differential equations(PDE's)(i.e.,oil,gas and water diffusion equations)into ordinary differential equations(ODE's)that are easily solved using the Runge-Kutta(RK)method.A modified time-power-law plot is also proposed to estimate the reservoir and fracture properties,recognizing that the classical square-root-of-time-plot is no longer valid when various reservoir complexities are exhibited *** the slope of the straight line on the modified time-power-law plot,the linear flow parameter can be estimated with more ***,because of the new Boltzmann-type transformation,reservoir and fracture properties can be derived more efficiently without the need for defining complex pseudo-variable *** the new semi-analytical model,the effects of multiphase flow,reservoir heterogeneity and anomalous diffusion on rate-decline behavior are *** the case of approximately constant flowing pressure,multiphase flow impacts initial oil rate,which is a funct

关键词： Transient linear flow Multiphase flow Reservoir heterogeneity Unconventional reservoirs

Visible-frequency nonvolatile reconfigurable Janus metasurfaces for dual-wavelength-switched and spin-asymmetric holograms

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Photonics Research 2024年第2期12卷 356-368页

作者： HUAN yuan ZHEQIANG ZHONG bin ZHANG College of Electronics and Information Engineering Sichuan UniversityChengdu 610064China Big Data Analysis and Fusion Application Technology Engineering Laboratory of Sichuan Province Chengdu 610065China

Janus metasurface holography with asymmetric transmission characteristics provides new degrees of freedom for multiplexing ***,earlier metasurfaces with asymmetrical transmission faced limitations in terms of tunability and *** this study,we propose a metasurface color holographic encryption scheme with dynamic switching and asymmetric transmission at visible frequencies using a low-loss nonvolatile optical phase-change material,Sb_(2)S_(3).Using a modified holographic optimization strategy,we achieved highfidelity asymmetric holographic imaging of a nanostructured *** controlling the incident direction and wavelength of visible light,as well as the level of crystallization of Sb_(2)S_(3),this reconfigurable metasurface enables the precise manipulation of tunable color holographic image *** particular,in the semi-crystalline state of Sb_(2)S_(3),the encoded information can be securely encrypted using a two-channel color-holographic image,whereas only a preset camouflaged image is displayed in the crystalline or amorphous state of Sb_(2)S_(3).The proposed multiencrypted Janus metasurface provides a potential approach for dynamic holographic displays with ultrahigh capacity,holographic encryption,and information storage.

关键词： holographic asymmetric visible

Direct identification of total and missing OH reactivities from light-duty gasoline vehicle exhaust in China based on LP-LIF measurement

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Journal of Environmental Sciences 2023年第11期133卷 107-117页

作者： Xuehui Liu Zibing yuan Qing’e Sha Shengrong Lou Hongli Wang Xin Li Junyu Zheng bin yuan Min Shao School of Environment and Energy South China University of TechnologyGuangzhou 510006China Institute of Environmental and Climate Research Jinan UniversityGuangzhou 511443China State Environmental Protection Key Laboratory of the Cause and Prevention of Urban Air Pollution Complex Shanghai Academy of Environmental SciencesShanghai 200233China College of Environmental Science and Engineering Peking UniversityBeijing 100871China

Considerable efforts have been devoted to characterising the chemical components of vehicle ***,these components may not accurately reflect the contribution of vehicle exhaust to atmospheric reactivity because of the presence of species not accounted for(“missing species”)given the limitations of analytical *** this study,we improved the laser photolysis–laser-induced fluorescence(LP-LIF)technique and applied it to directly measure the total OH reactivity(TOR)in exhaust gas from light-duty gasoline vehicles in *** TOR for China Ⅰ to Ⅵ-a vehicles was 15.6,16.3,8.4,2.6,1.5,and 1.6×10^(4) sec^(-1),respectively,reflecting a notable drop as emission standards were *** TOR was comparable between cold and warm *** missing OH reactivity(MOR)values for China Ⅰ to Ⅳ vehicles were close to zero with a cold start but were much higher with a warm *** variations in oxygenated volatile organic compounds(OVOCs)under different emission standards and for the two start conditions were similar to those of the MOR,indicating that OVOCs and the missing species may have similar production *** measurement revealed that the duration of the stable driving stage was the primary factor leading to the production of OVOCs and missing *** findings underscore the importance of direct measurement of TOR from vehicle exhaust and highlight the necessity of adding OVOCs and other organic reactive gases in future upgrades of emission standards,such that the vehicular contribution to atmospheric reactivity can be more effectively controlled.

关键词： Total OH reactivity LP-LIF Missing OH reactivity Emission standard Light-duty gasoline vehicle

Review on modification routes for SnO_(x)-based anodes for Li storage:morphological structure tuning and phase structure design

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Rare Metals 2023年第9期42卷 2840-2867页

作者： Yu Zheng Xue-Xia Lan Xing-Yu Xiong bin yuan Ren-Zong Hu School of Materials Science and Engineering Guangdong Provincial Key Laboratory of Advanced Energy Storage MaterialsSouth China University of TechnologyGuangzhou510640China

Fascinating with high specific capacity and moderate lithiation potential,SnO_(x)-based materials have been intensively investigated as one of the most promising anodes for lithium-ion ***,due to poor cycling stability,sluggish reaction kinetics,and limited electrochemical reaction reversibility,the development of SnO_(x)-based anodes has been *** the current preparation and modification routes for SnO_(x)-based anodes lack direct and specific ***,modification routes for SnO_(x)-based anodes have been ***,to provide more direct instructions,the tuning routes of morphological structure for SnO_(x)-based electrodes(including slurry-based and self-supported)have been thoroughly discussed from the preparation ***,according to the properties of SnO_(x)-based anodes,the phase structure design ideas have also been properly classified and organized for addressing chemical reaction kinetics or thermodynamic ***,for future-oriented studies,new insights into the development and commercialization prospects of SnO_(x)-based anodes are also *** review,with comprehensive information on SnO_(x)-based anodes,aims to bring more specific guidance and valuable inspiration for peer researchers who are promoting the application of SnO_(x)-based materials for energy conversion and storage devices.

关键词： Lithium-ion battery(LIB) SnO_(x)-based anodes Reaction kinetics Morphological structure tuning Phase structure design

Research on dual-command operation path optimization based on Flying-V warehouse layout

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High Technology Letters 2023年第4期29卷 388-396页

作者：刘建胜 yuan bin YANG Zan ZHONG RAY Y School of Advanced Manufacturing Nanchang UniversityNanchang 330031P.R.China Department of Industrial and Manufacturing Systems Engineering University of Hong KongHong Kong 999077P.R.China

To enhance the efficiency of warehouse order management,this study investigates a dual-com-mand operation mode in the Flying-V non-traditional warehouse *** dual-command opera-tion strategies are designed,and a dual-command operation path optimization model is established with the shortest path as the optimization ***,a genetic algorithm based on a dynamic decoding strategy is *** results demonstrate that the Flying-V layout warehouse management and access cooperation operation can reduce the operation time by an average of 25%-35%compared with the single access operation path,and by an average of 13%-23%compared with the‘deposit first and then pick’operation *** findings provide evidence for the effec-tiveness of the optimization model and algorithm.

关键词： Flying-V access collaboration path optimization dynamic decoding genetic al-gorithm

在市区非机动车道上抛撒刀片赚取修车费用的行为该如何定性

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人民检察 2024年第12期 37-44页

作者：王小飞袁彬王立琴马玮玮《人民检察》北京师范大学刑事法律科学研究院最高人民检察院重大犯罪检察厅上海市静安区人民检察院

近期,行为人出于不同目的在道路上抛撒危险物品影响交通安全的案件时有发生。由于作案时间、地点、物品类型、目的动机、危害结果不同,在认定该类案件事实、适用法律方面存在分歧。为厘清办案难点,解决争议问题,高质效办好案件,推进道... 详细信息

近期,行为人出于不同目的在道路上抛撒危险物品影响交通安全的案件时有发生。由于作案时间、地点、物品类型、目的动机、危害结果不同,在认定该类案件事实、适用法律方面存在分歧。为厘清办案难点,解决争议问题,高质效办好案件,推进道路交通安全治理,本刊特述选一起在城市道路非机动车道上放置刀片赚取修车费用的案件,邀请法学专家和检察官对有关问题进行研讨,敬请关注。

关键词：作案时间案件事实非机动车道危害结果危险物品交通安全法学专家检察官

Intelligent identification and real-time warning method of diverse complex events in horizontal well fracturing

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Petroleum Exploration and Development 2023年第6期50卷 1487-1496页

作者： yuan bin ZHAO Mingze MENG Siwei ZHANG Wei ZHENG He School of Petroleum Engineering China University of Petroleum(East China)Qingdao 266580China PetroChina Research Institute of Petroleum Exploration&Development Beijing 100083China

The existing approaches for identifying events in horizontal well fracturing are difficult, time-consuming, inaccurate, and incapable of real-time warning. Through improvement of data analysis and deep learning algorithm, together with the analysis on data and information of horizontal well fracturing in shale gas reservoirs, this paper presents a method for intelligent identification and real-time warning of diverse complex events in horizontal well fracturing. An identification model for "point" events in fracturing is established based on the Att-BiLSTM neural network, along with the broad learning system (BLS) and the BP neural network, and it realizes the intelligent identification of the start/end of fracturing, formation breakdown, instantaneous shut-in, and other events, with an accuracy of over 97%. An identification model for "phase" events in fracturing is established based on enhanced Unet++ network, and it realizes the intelligent identification of pump ball, pre-acid treatment, temporary plugging fracturing, sand plugging, and other events, with an error of less than 0.002. Moreover, a real-time prediction model for fracturing pressure is built based on the Att-BiLSTM neural network, and it realizes the real-time warning of diverse events in fracturing. The proposed method can provide an intelligent, efficient and accurate identification of events in fracturing to support the decision-making.

关键词： horizontal well fracturing fracturing events intelligent identification real-time warning deep learning

基于多感受野特征增强的改进EfficientDet遥感目标检测算法

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电光与控制 2024年第7期31卷 53-60,96页

作者：张润梅贾振楠李佳祥吴路路徐信芯袁彬安徽建筑大学机械与电气工程学院合肥230000 安徽省工程机械智能制造重点实验室合肥230000 陕西省高速公路施工机械重点实验室西安710000 安徽省仿真设计与现代制造工程技术研究中心安徽芜湖241000 安徽工程大学安徽芜湖241000

针对遥感图像目标检测中小目标检测精度低、目标密集和尺度形态多样等问题,在轻量化网络EfficientDet-D0目标检测算法的基础上,在加权双向特征金字塔网络(BiFPN)进行特征融合时加入小尺度以及高一级尺度的中间信息,对BiFPN网络进行重构... 详细信息

针对遥感图像目标检测中小目标检测精度低、目标密集和尺度形态多样等问题,在轻量化网络EfficientDet-D0目标检测算法的基础上,在加权双向特征金字塔网络(BiFPN)进行特征融合时加入小尺度以及高一级尺度的中间信息,对BiFPN网络进行重构,充分利用不同尺度信息,提高多尺度目标检测精度;同时在BiFPN中加入融合空洞卷积和快速归一化融合方法的特征增强模块,补强因特征图缩放所丢失的特征信息,进一步提高检测精度;另外,采用参数动态的Dynamic ReLU激活函数对原始网络中的参数静态的Swish激活函数进行改进。改进EfficientDet算法在不影响轻量化特点的前提下,对公开数据集Pascal VOC的目标检测平均精度均值(mAP)相较于原始算法提升11.9个百分点,亦优于其他目标检测算法。针对遥感图像数据集RSOD,通过Imgaug数据增强库对已有的936幅遥感图像数据集进行数据增广,利用改进模型进行迁移学习,未进行数据增广和增广后的目标检测结果分别为88.38%和96.78%,证明所提算法可以满足实际应用中对遥感图像目标的检测要求。

关键词：深度学习遥感图像目标检测 EfficientDet 多尺度特征融合特征增强模块 Dynamic ReLU

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