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光热催化百叶型Trombe墙性能的实验探究

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太阳能学报 2024年第1期45卷 73-79页

作者：顾涛车磊李念思余本东南京工业大学城市建设学院南京210009 中国科学技术大学热科学和能源工程系合肥230027

针对Trombe墙存在夏季过热、冬季室内污染物易积累等问题,提出光热催化百叶型Trombe墙新系统,在冬季实现采暖和甲醛净化、夏季实现净化的同时,能将太阳辐射反射到室外,缓解室内过热。光热催化百叶能同时利用光能和热能驱动催化净化反应... 详细信息

针对Trombe墙存在夏季过热、冬季室内污染物易积累等问题,提出光热催化百叶型Trombe墙新系统,在冬季实现采暖和甲醛净化、夏季实现净化的同时,能将太阳辐射反射到室外,缓解室内过热。光热催化百叶能同时利用光能和热能驱动催化净化反应,还可产生协同效应来增强反应效率。首先探究不同比例的光热催化剂对甲醛降解性能的影响,并测试不同甲醛浓度、紫外辐照度和催化温度条件下的甲醛降解性能,揭示太阳辐射作用下的光热协同净化效应;然后搭建光热催化百叶型Trombe墙实验测试系统,探究不同太阳辐照度和百叶翻转角度下光热催化百叶型Trombe墙的热性能和甲醛降解性能。研究结果表明:光热催化剂比例为10%的光热复合催化剂的除醛效率最佳;太阳辐射使得光热复合催化剂的活化能降低了14.46%~31.25%,产生了光热协同效应;光热催化百叶型Trombe墙的采暖效率可达到46.21%,每小时产生的干净空气量(CADr)最大为81.47 m^(3)/h,且墙体的采暖效率和甲醛净化效率均随太阳辐照度和百叶翻转角度的增大而增大。

关键词： Trombe墙百叶采暖净化光热协同催化

活塞环表面moS_(2)薄膜在干摩擦和贫油润滑条件下的摩擦学性能研究

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材料保护 2024年第3期57卷 80-87页

作者：李楠车银辉王铭昌苏州热工研究院有限公司广东深圳518000

大功率、长冲程和高爆发压柴油机是交通运输、工程机械、国防装备和核电应急发电机领域的重要动力设备。柴油机关键运动副活塞环-缸套在冷/热启动时,缸套的上下止点位置处于干摩擦或贫油润滑状态,易发生局部异常磨损导致动力性能丧失。... 详细信息

大功率、长冲程和高爆发压柴油机是交通运输、工程机械、国防装备和核电应急发电机领域的重要动力设备。柴油机关键运动副活塞环-缸套在冷/热启动时,缸套的上下止点位置处于干摩擦或贫油润滑状态,易发生局部异常磨损导致动力性能丧失。为抑制活塞环-缸套运动副的异常磨损,采用磁控溅射技术在活塞环表面制备了moS_(2)薄膜;利用SrV-IV微动摩擦磨损试验机模拟柴油机频繁冷/热启动工况,评价了表面附加moS_(2)薄膜的活塞环与缸套摩擦副的摩擦学性能;利用扫描电镜(SEm)表征了moS_(2)薄膜微观结构和摩擦前后摩擦副的表面形貌。结果表明:相比于原始CKS活塞环-缸套,moS_(2)薄膜活塞环-缸套在干摩擦条件下的摩擦系数从1.07大幅降低至0.11,缸套磨损率从8.61×10^(-6) mm^(3)/(N·m)降低至3.71×10^(-8) mm^(3)/(N·m);在常温贫油条件下摩擦系数从0.18降低至0.11,磨损率从1.43×10^(-7) mm^(3)/(N·m)降低至3.22×10^(-8) mm^(3)/(N·m);在高温贫油条件下摩擦系数从0.12降低至0.08,磨损率从7.08×10^(-8) mm^(3)/(N·m)降低至1.12×10^(-8 )mm^(3)/(N·m);摩擦过程中活塞环表面moS_(2)薄膜的转移是摩擦副摩擦学性能提升的主要原因。

关键词：活塞环-缸套 moS_(2)薄膜磁控溅射摩擦磨损性能

Design of a combined magnetic negative stiffness mechanism with high linearity in a wide working region

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Science China(Technological Sciences) 2022年第9期65卷 2127-2142页

作者： WU JiuLin che JiXing cheN XueDong JIANG Wei State Key Laboratory of Digital manufacturing Equipment and Technology Huazhong University of Science and TechnologyWuhan 430074China

Combining magnetic negative stiffness mechanism(NSm) in parallel with positive stiffness has been considered to be an effective approach to realize the quasi-zero stiffness(QZS) characteristic,thus resolving the contradiction between high load capacity and(ultra-) low-frequency vibration isolation ***,the rem.r.able stiffness nonlinearity of common magnetic NSms restricts the displacement region with reliable negative stiffness,resulting in considerable nonlinear behavior,poor vibration attenuation performance,and probable instability under large amplitude vibrations.A novel combined negative stiffness mechanism(CNSm) with attractive magnetic NSm(ANSm) and repulsive magnetic NSm.r.Sm) in parallel is proposed in this *** stiffness nonlinearities of the ANSm and rNSm in the CNSm are counteracted through the parallel configuration such that the displacement region with reliable linear stiffness of the CNSm is widened by several *** analytical model of the CNSm is established by the magnetic charge model and verified by simulation on ANSYS *** studies are then conducted to investigate the effects of design parameters on the stiffness characteristic,providing guidelines for the optimal design of the ***,the stiffness and nonlinearity of the CNSm are compared with that of a single ANSm and *** and dynamic experiments are finally conducted on the proposed test *** results demonstrated the validity of the established model and the effectiveness of the CNSm in generating high linear stiffness within a wide displacement region and lowering the resonance ***,the proposed CNSm can be applied in(ultra-) low-frequency vibration isolation under large amplitude excitations.

关键词： vibration isolation quasi-zero stiffness combined negative stiffness mechanism high linearity

睡美人2000——基于诺贝尔生理学或医学奖的一种引领性原创成果文献评价指标

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中国科学：生命科学 2024年第2期54卷 349-356页

作者：高东平车美龄魏晓瑶杨渊林建海中国医学科学院医学信息研究所北京100020

为了挖掘“引领性原创成果”特征,本文基于对获诺贝尔生理学或医学奖学者代表性文献的分析,给出了一种具有可操作性的“引领性原创”文献识别指标睡美人2000,并将其推广为一种以“时间-实践”双维度反映文献超前性、广泛关注性的评价范... 详细信息

为了挖掘“引领性原创成果”特征,本文基于对获诺贝尔生理学或医学奖学者代表性文献的分析,给出了一种具有可操作性的“引领性原创”文献识别指标睡美人2000,并将其推广为一种以“时间-实践”双维度反映文献超前性、广泛关注性的评价范式“睡美人T-N”.

关键词：睡美人睡美人2000 生物医学文献成果文献评价指标

Battery impedance spectrum prediction from partial charging voltage curve by machine learning

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Journal of Energy chemistry 2023年第4期79卷 211-221页

作者： Jia Guo Yunhong che Kjeld Pedersen Daniel-Ioan Stroe AAU Energy Aalborg UniversityAalborg 9220Denmark Department of materials and Production Aalborg UniversityAalborg 9220Denmark

Electrochemical impedance spectroscopy(EIS) is an effective technique for Lithium-ion battery state of health diagnosis, and the impedance spectrum prediction by battery charging curve is expected to enable battery impedance testing during vehicle operation. However, the mechanistic relationship between charging curves and impedance spectrum.r.mains unclear, which hinders the development as well as optimization of EIS-based prediction techniques. In this paper, we predicted the impedance spectrum by the battery charging voltage curve and optimized the input based on electrochemical mechanistic analysis and machine learning. The internal electrochemical relationships between the charging curve,incremental capacity curve, and the impedance spectrum are explored, which im.r.ves the physical interpretability for this prediction and helps define the proper partial voltage range for the input for machine learning models. Different machine learning algorithms have been adopted for the verification of the proposed framework based on the sequence-to-sequence predictions. In addition, the predictions with different partial voltage ranges, at different state of charge, and with different training data ratio are evaluated to prove the proposed method have high generalization and robustness. The experimental results show that the proper partial voltage range has high accuracy and converges to the findings of the electrochemical analysis. The predicted errors for impedance spectrum are less than 1.9 mΩ with the proper partial voltage range selected by the corelative analysis of the electrochemical reactions inside the batteries. Even with the voltage range reduced to 3.65–3.75 V, the predictions are still reliable with most rmSEs less than 4 mO.

关键词： Impedance spectrum prediction Lithium-ion battery machine learning EIS Graphite anode

曲美他嗪治疗缺血性心肌病心力衰竭房性心律失常的疗效观察

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中国基层医药 2024年第2期31卷 185-190页

作者：李澈褚振亮蒋芬芬陆琴黄忆嘉兴市第二医院心血管内科嘉兴314000

目的观察曲美他嗪治疗缺血性心肌病心力衰竭导致房性心律失常患者的疗效,分析曲美他嗪对患者心功能及房性心律失常的影响。方法选取嘉兴市第二医院2018年12月至2020年6月收治的缺血性心肌病心力衰竭患者79例进行随机对照研究,采用随机... 详细信息

目的观察曲美他嗪治疗缺血性心肌病心力衰竭导致房性心律失常患者的疗效,分析曲美他嗪对患者心功能及房性心律失常的影响。方法选取嘉兴市第二医院2018年12月至2020年6月收治的缺血性心肌病心力衰竭患者79例进行随机对照研究,采用随机数字表法分为观察组41例、对照组38例。对照组予常规药物治疗,观察组在对照组基础上加用曲美他嗪缓释片35 mg/次,2次/d,治疗24周。分析两组治疗前后心功能指标[左心室射血分数(LVEF)、B型脑钠肽(BNP)、6 min步行距离(6mWD)]、心脏彩色多普勒超声指数[E峰与A峰比值(E/A)、左心室短轴缩短率(LVFS)]、心电图参数[P波最大时限(Pmax)、P波最小时限(Pmin)与P波离散度(Pdisp)]、动态心电图参数[单个房性早搏数量、短阵房速总数及持续时间、阵发性房扑/房颤总数及持续时间、rr间期的标准差(SDNN)、相邻rr间期差值的均方根(rmSSD)、相邻NN之差>50 ms的个数占总窦性心搏个数的百分比(PNN50)、rr间期平均值标准差(SDANN)、高频功率(HF)、低频功率(LF)]和超敏C反应蛋白(hs-CrP)的变化。结果治疗后,观察组LVEF、BNP、6mWD、Pmax、Pdisp、房扑/房颤总数、房扑/房颤持续时间分别为(51.05±7.68)%、(1615.59±1129.78)ng/L、(350.02±62.99)m、(99.73±11.60)ms、(22.44±12.03)ms、(0.22±0.61)、(4.59±12.30)min,均明显优于对照组的(46.82±7.34)%、(2267.47±1539.03)ng/L、(294.16±58.20)m、(111.71±10.00)ms、(36.77±15.07)ms、(0.76±1.13)、(15.66±22.30)min,差异均有统计学意义(t=-2.95、2.16、-4.08、4.89、4.68、2.69、2.76,均P<0.01)。结论曲美他嗪能改善缺血性心肌病心力衰竭患者的房性心律失常,改善其预后,值得临床推广。

关键词：心力衰竭心律失常,心性心肌疾病冠心病心电描记术,便携式利钠肽,脑曲美他嗪

A9.8-30.1GHzCmOSlow-noise amplifier with a 3.2-dB noise figure using inductor-and transform.r.based gm-boosting techniques

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Frontiers of Information Technology & Electronic Engineering 2021年第4期22卷 586-598页

作者： Hongchen cheN Haoshen ZHU LiangWU Wenquan che Quan XUE Guangdong Provincial Key Laboratory of millimeter-Wave and Terahertz School of Electronic and Information EngineeringSouth China University of TechnologyGuangzhou 510641China School of Science and Engineering The Chinese University of Hong KongShenzhenShenzhen 518172China

A 9.8–30.1 GHz CmOS low-noise amplifier(LNA)with a 3.2-dB minimum noise figure(NF)is *** the architecture level,a topology based on common-gate(CG)cascading with a common-source(CS)amplifier is proposed for simultaneous wideband input matching and relatively high *** the circuit level,multiple techniques are proposed to im.r.ve LNA ***,in the CG stage,loading effect is properly used instead of the conventional feedback technique,to enable simultaneous impedance and noise ***,based on in-depth theoretical analysis,the inductor-and transform.r.based gm-boosting techniques are employed for the CG and CS stages,respectively,to enhance the gain and reduce power ***,the floating-body method,which was originally proposed to lower NF in CS amplifiers,is adopted in the CG stage to further reduce *** in a 65-nm CmOS technology,the LNA chip occupies an area of only 0.2 mm^(2)and measures a maximum power gain of 10.9 dB with−3 dB bandwidth from 9.8 to 30.1 *** NF exhibits a minimum value of 3.2 dB at 15 GHz and is below 5.7 dB across the entire *** LNA consumes 15.6 mW from a 1.2-V supply.

关键词： CmOS gm-boosting Low-noise amplifier Transformer Common-gate

安装水平多孔板的鼓泡床反应器CFD-PBm数值模拟

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石油学报（石油加工） 2024年第3期40卷 727-734页

作者：霍莹付连超王娟车连发李秀明阚子建刘翊辉中海油天津化工研究设计院有限公司天津300131 中国石油大学重质油国家重点实验室北京102249

采用Euler-Euler双流体模型对安装水平多孔板的鼓泡床反应器内气-液两相流动进行数值模拟研究,探究了不同水平多孔板和表观气速条件对鼓泡床反应器内气含率及气泡直径的影响。结果表明:当表观气速从0.5 m/s增加到1.0 m/s时,安装水平多... 详细信息

采用Euler-Euler双流体模型对安装水平多孔板的鼓泡床反应器内气-液两相流动进行数值模拟研究,探究了不同水平多孔板和表观气速条件对鼓泡床反应器内气含率及气泡直径的影响。结果表明:当表观气速从0.5 m/s增加到1.0 m/s时,安装水平多孔板的反应器内整体气含率显著增加;安装多孔板后,气泡在中心区域分布范围加宽;轴向液体速度为0时,没有安装多孔板的反应器向上流动的液相径向无量纲分布范围为0~0.57,而安装了多孔板的径向无量纲分布范围为0~0.64;水平多孔板的安装能增强气泡之间的聚并与破碎,使大气泡在反应器中心区域的分散范围更宽。

关键词：鼓泡床反应器 CFD-PBm模型轴向液速气含率

UAV-Assisted Data Offloading for Sm.r. Container in Offshore m.r.time Communications

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China Communications 2022年第1期19卷 153-165页

作者： Yanpeng Dai Bin Lin Yudi che Ling Lyu School of Information Science and Technology Dalian Maritime UniversityDalian 116026China Network Communication research Centre Peng Cheng LaboratoryShenzhen 518052China State Key Laboratory of Integrated Services Networks Xidian UniversityShaanxi 710071China

Sm.r. containers have been extensively applied in the m.r.time industry by em.r.cing the Internet of Things to realize container status monitoring and data offloading without human ***, the offloading rate and delay in the offshore region are limited by the coverage of the onshore base station(BS). In this paper, we investigate the unmanned aerial vehicle(UAV)-assisted data offloading for sm.r. containers in offshore m.r.time communications where the UAV is as a relay node between sm.r. containers and onshore BS. We first consider the mobility of container vessel in the offshore region and establish a UAV-assisted data offloading model. Based on this model, a data offloading algorithm is proposed to reduce the average offloading delay under data-size requirements and available energy constraints of sm.r. containers. Specifically, the convex-concave procedure is used to update time-slot assignment,offloading approach selection, and power allocation in an iterative manner. Simulation results show that the proposed algorithm can efficiently reduce average offloading delay and increase offloading success ***, it is shown that the UAV relay cannot always bring the performance gain on offloading delay especially in the close-to-shore area, which could give an insight on the deployment of UAV relay in offshore communications.

关键词： data offloading sm.r. container unmanned aerial vehicle m.r.time Internet of Things