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A Distinctive Pattern for Substituent Effects on Transition Metal Centers:Enhanced Electron-Donating Capacity of Cationic Palladium Species

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CCS Chemistry 2023年第5期5卷 1163-1175页

作者： Jun-Yan Wu Bin-Rui Mo jin-dong Yang jin-Pei Cheng Department of Chemistry Tsinghua UniversityBeijing 100084 College of Chemistry Nankai UniversityTianjin 300071 Haihe Laboratory of Sustainable Chemical Transformations Tianjin 300192

Electronic and bonding situations at reaction centers are often detected by the remote substituent *** nonorganometallic reactions,this effect is conventionally described by the well-known Hammett-type substituent ***,for most transition metal(TM)-involved systems,no analogous numeral descriptors reflecting the intrinsic differences between metallic and nonmetallic bonding have been rigorously established till ***,we report a Pd(II)–O bond heterolysis energyΔG_(het)(Pd–O)study of the archetypal palladium complexes to represent the thermodynamics of the essential bond-breaking step in Pd-mediated *** we furnish the new substituent constantsσPd^(+)s and therefrom facilitate linear free-energy relationship(LFER)analysis for Pd-catalyzed ***,this led us to find an unexpected electron-donating ability of Pd(II)cation,which provided a gifted experimental support,with the aid of computation,to attribute the frustrating observation of a much scattered curvature in theΔG_(het)(Pd–O)-σ+correlation to the electrondonating capacity of the cationic palladium through back-donation of its *** of LFER analysis withσPd^(+)to predict the redox behavior of the palladium complex and in a kinetics *** study of transmetalation added further credence to their applicability to TM systems.

关键词： bond dissociation energy substituent effects palladium complexes thermodynamics structure–reactivity relationship

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国密SM4算法CBC模式的高效设计与实现

计算机研究与发展 2024年第6期61卷 1450-1457页

作者：郝泽钰代天傲黄亦成段岑林董进吴世勇张博王雪岩贾小涛杨建磊北京航空航天大学计算机学院北京100191 北京市未来区块链与隐私计算高精尖创新中心北京100191 北京微芯区块链与边缘计算研究院北京100080

密码技术是现代信息安全技术产业发展的核心,其中,国密SM4分组密码算法因其硬件实现简单、效率高等优点,已广泛应用于加密传输、加密存储等领域.随着应用领域的不断扩展,对硬件加密效率的需求也随之提高.目前,借助流水线技术,基于ASIC... 详细信息

密码技术是现代信息安全技术产业发展的核心,其中,国密SM4分组密码算法因其硬件实现简单、效率高等优点,已广泛应用于加密传输、加密存储等领域.随着应用领域的不断扩展,对硬件加密效率的需求也随之提高.目前,借助流水线技术,基于ASIC实现的SM4算法在ECB(electronic code book)工作模式下能够达到较高的吞吐量.然而,在CBC(cipher block chaining)模式下,由于相邻的数据存在依赖关系,流水线技术难以提高硬件设计的吞吐率.为解决这一问题,提出了2种逻辑化简方法:一种作用于轮函数迭代过程,另一种作用于S盒置换过程.这2种方法在每一轮迭代的关键路径中均减少了2个异或运算的延时.在TSMC 40 nm工艺下的ASIC综合结果表明,该设计在CBC模式下的吞吐率达到4.2 Gb/s,单位面积吞吐量达129.4 Gb·s^(-1)·mm^(-2),高于已发表的同类设计.

关键词：国密SM4算法 CBC模式硬件加速高效设计 ASIC

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不同药用植物根际土壤原核微生物多样性研究

微生物学杂志 2024年第1期44卷 90-99页

作者：李运涛孟忠祥董晋苏佳铭李欢吕超田蚌埠学院食品与生物工程学院安徽蚌埠233030

为研究不同药用植物根际土壤中的原核微生物多样性,分别采集白术(Atractylodes macrocephala)、白芍(Paeonia sterniana)、牡丹(Paeonia suffruticosa)、玄参(Scrophularia ningpoensis)四种药用植物的根际土壤以及非种植区的土壤,针对16S rRNA基因的V3~V4区进行测序,分析土壤细菌群落的组成。结果表明,药用植物根际土壤中的细菌群落多样性指数显著高于非种植区土壤。五组样本的优势类群差异不大,总体相对丰度较高的有变形菌门(Proteobacteria)、酸杆菌门(Acidobacteria)、放线菌门(Actinobacteria)、芽单胞菌门(Gemmatimonadetes)、绿弯菌门(Chloroflexi)等,药用植物根际中的放线菌相对丰度高于非种植区。属水平上四种药用植物根际细菌和非种植区的群落结构有较大差异,四种中药材的根际土壤中各自富集了特异性的有益细菌属。药用植物根际土壤中的NMD1、dongia、Gaiella、Streptomyces等相对丰度高于非种植区,而非种植区土壤中Lysobacter相对丰度显著高于药用植物。此外,四种中药材的根际土壤中硝酸盐还原和芳香族化合物降解功能被富集。

关键词：药用植物微生物多样性高通量测序根际土壤原核微生物

Surface-Enhanced Raman Spectroscopy:Principles,Methods,and Applications in Energy Systems

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Chinese Journal of Chemistry 2023年第3期41卷 355-369页

作者： Quan-Feng He Yu-jin Zhang Zhi-Lan Yang jin-Chao dong Xiu-Mei Lin Jian-Feng Li State Key Laboratory of Physical Chemistry of Solid Surfaces College of Chemistry and Chemical EngineeringCollege of EnergyiChEMXiamen UniversityXiamenFujian361005 China Innovation Laboratory for Sciences and Technologies of Energy Materials of Fujian Province(IKKEM) XiamenFujian361005 China Department of Chemistry and Environment Science Fujian Province University Key Laboratory of Analytical ScienceMinnan Normal UniversityZhangzhouFujian363000 China Shenzhen Research Institute of Xiamen University ShenzhenGuangdong518000 China

Surface-enhanced Raman spectroscopy(SERS)has advanced significantly since its *** experimental and theoretical efforts have been made to understand the SERS effect and demonstrate its *** to its extremely high sensitivity and selectivity and ability to provide molecular fingerprint information,SERS has a wide range of applications in surface and interfacial chemistry,energy,materials,biomedicine,environmental analysis,*** review aims to provide readers with an understanding of the principles,methodologies,and applications of *** briefly introduce the fundamental theory of the SERS enhancement mechanism and summarize the details of the preparation of SERS-active *** applications of SERS in energy systems are then highlighted,including probing surface reactions and interfacial charge transfer of batteries and ***,the challenges and prospects of SERS research are discussed.

关键词： Surface-enhance Raman spectroscopy In situ characterization Li-ion batteries Water splitting Fuel cells

智能技术在智慧工地中的应用研究——以顶管工程为例

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辽宁工业大学学报（自然科学版） 2024年第3期44卷 181-187页

作者：刘袁辰董锦坤贾君张玉桂辽宁工业大学土木建筑工程学院辽宁锦州121001 北京金河水务建设有限公司北京102200 中交路桥北方工程有限公司北京100000

传统顶管工程施工工地具有地下施工长度大、有害气体含量高、施工作业面在水位线以下等特点,存在施工安全风险系数高、监管难度大等问题。故以南水北调顶管工程为例,研究了智能技术在施工工地安全管理、进度监管、数据管理、人员管理等... 详细信息

传统顶管工程施工工地具有地下施工长度大、有害气体含量高、施工作业面在水位线以下等特点,存在施工安全风险系数高、监管难度大等问题。故以南水北调顶管工程为例,研究了智能技术在施工工地安全管理、进度监管、数据管理、人员管理等方面的应用,结果表明,合理运用智能技术能够实现对施工过程中的人员、环境危险源、设备数据的有效管理,从而提升工程施工管理质量与水平,促进工程管理向智能化的方向发展。

关键词：智能技术智能监测顶管施工智慧工地

基于ANSYS的双螺杆挤出机长圆形夹套的优化设计

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化工机械 2024年第4期51卷 600-608页

作者：柏凯旋董金善孙项羽王涛南京工业大学机械与动力工程学院

对双螺杆挤出机长圆形夹套结构进行优化设计,在夹套外表面设置加强圈可以有效降低结构的最大应力和总变形量,进而减薄长圆形夹套的厚度。利用数值模拟分析方法对比不同截面形状的加强圈对结构的加强效果,发现L形截面加强圈对应力的影响... 详细信息

对双螺杆挤出机长圆形夹套结构进行优化设计,在夹套外表面设置加强圈可以有效降低结构的最大应力和总变形量,进而减薄长圆形夹套的厚度。利用数值模拟分析方法对比不同截面形状的加强圈对结构的加强效果,发现L形截面加强圈对应力的影响最为显著。确定合适的加强圈数量,利用ANSYS Workbench参数化优化平台,采用80组随机取样和等步长运算,分析各参数对夹套结构应力的敏感性。研究结果表明:加强圈厚度S、高度H、宽度L和夹套厚度T对夹套结构应力、变形的影响较为显著,而套管厚度t对其应力、变形几乎没有影响。基于目标驱动优化确定最佳结构。此时,长圆形夹套厚度减薄60%,设备总质量降低17.42%。

关键词：双螺杆挤出机加强圈长圆形夹套结构强度优化设计

Adaptive Momentum-Backpropagation Algorithm for Flood Prediction and Management in the Internet of Things

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Computers, Materials & Continua 2023年第10期77卷 1053-1079页

作者： Jayaraj Thankappan Delphin Raj Kesari Mary dong jin Yoon Soo-Hyun Park Department of Computer Science Muslim Arts CollegeManonmaniam Sundaranar UniversityThiruvitancodeTamil Nadu629174India Laboratory Special Communication&Convergence Service Research Center Kookmin UniversitySeoul02707Korea Development and Operation Support of Polar Research Equipment Korea Polar Research Institute(KOPRI)Incheon21990Korea Department of Financial Information Security Kookmin UniversitySeoul02707Korea

Flooding is a hazardous natural calamity that causes significant damage to lives and infrastructure in the real ***,timely and accurate decision-making is essential for mitigating flood-related *** traditional flood prediction techniques often encounter challenges in accuracy,timeliness,complexity in handling dynamic flood patterns and leading to substandard flood management *** address these challenges,there is a need for advanced machine learning models that can effectively analyze Internet of Things(IoT)-generated flood data and provide timely and accurate flood *** paper proposes a novel approach-the Adaptive Momentum and Backpropagation(AM-BP)algorithm-for flood prediction and management in IoT *** AM-BP model combines the advantages of an adaptive momentum technique with the backpropagation algorithm to enhance flood prediction accuracy and ***-world flood data is used for validation,demonstrating the superior performance of the AM-BP algorithm compared to traditional *** addition,multilayer high-end computing architecture(MLCA)is used to handle weather data such as rainfall,river water level,soil moisture,*** AM-BP’s real-time abilities enable proactive flood management,facilitating timely responses and effective disaster ***,the AM-BP algorithm can analyze large and complex datasets,integrating environmental and climatic factors for more accurate flood *** evaluation result shows that the AM-BP algorithm outperforms traditional approaches with an accuracy rate of 96%,96.4%F1-Measure,97%Precision,and 95.9%*** proposed AM-BP model presents a promising solution for flood prediction and management in IoT networks,contributing to more resilient and efficient flood control strategies,and ensuring the safety and well-being of communities at risk of flooding.

关键词： Internet of Things flood prediction artificial neural network adaptive momentum backpropagation optimization disaster management

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预应力加强框架节点的抗震性能研究综述

辽宁工业大学学报（自然科学版） 2024年第3期44卷 177-180页

作者：肖体德董锦坤许淞清辽宁工业大学土木建筑工程学院辽宁锦州121001 中交路桥建设有限公司北京100000

通过总结国内外预应力加强框架节点的实验及数值模拟研究,分析了不同加强形式对框架节点的影响,结果表明:预应力加强节点与传统节点相比具有更好的承载力及抗剪强度,能提升结构的抗震性能。最后,对预应力加强框架节点研究进行了总结与... 详细信息

通过总结国内外预应力加强框架节点的实验及数值模拟研究,分析了不同加强形式对框架节点的影响,结果表明:预应力加强节点与传统节点相比具有更好的承载力及抗剪强度,能提升结构的抗震性能。最后,对预应力加强框架节点研究进行了总结与展望。

关键词：预应力钢筋混凝土框架节点数值模拟

Preface to the special issue on low carbon and environmental protection

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Journal of Central South University 2022年第7期29卷 2099-2100页

作者：金东寒 CIMAC Tianjin University CSICE CAE

With growing economic and social development, carbon emissions caused by energy consumption surge, leading to an exacerbated greenhouse effect, rising average temperatures,melting glaciers, and an unstable global clim... 详细信息

关键词： greenhouse carbon unstable