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2D-SiC/SiC复合材料的弹丸冲击损伤及冲击后拉伸性能

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无机材料学报 2024年第5期39卷 494-500页

作者：李广宇岳一凡王波张程煜索涛李玉龙西北工业大学航空学院西安710072 陕西省冲击动力学及工程应用重点实验室西安710072 强度与结构完整性全国重点实验室西安710065 西北工业大学材料学院西安710072 西北工业大学民航学院西安710072

连续纤维增韧陶瓷基复合材料以其良好的高温性能而被广泛应用在航空发动机等高温部件处,但服役过程中容易受到异物碎片冲击,这受到了广泛关注。研究采用轻气炮对化学气相渗透(CVI)技术制备的2D-SiC/SiC试样进行弹丸冲击,利用高速摄像机... 详细信息

连续纤维增韧陶瓷基复合材料以其良好的高温性能而被广泛应用在航空发动机等高温部件处,但服役过程中容易受到异物碎片冲击,这受到了广泛关注。研究采用轻气炮对化学气相渗透(CVI)技术制备的2D-SiC/SiC试样进行弹丸冲击,利用高速摄像机记录冲击过程,使用光学显微镜和CT观察异物损伤(FOD)的表面和内部结构,探讨了2D-SiC/SiC复合材料的高速冲击损伤特性。结果表明,2D-SiC/SiC复合材料的高速冲击损伤形式包括锥形裂纹、层间分层、纤维断裂以及基体压溃等。通过表征损伤发现,试件背部损伤和边缘处分层损伤由反射拉伸波造成,随着冲击速度提升,弹丸与拉伸波共同作用会造成试件穿透,试件边缘分层损伤减弱。对高速冲击后的试件进行准静态拉伸试验,明确了剩余力学性能与冲击速度、弹丸直径的关系,表明剩余拉伸强度是表征冲击损伤程度的有效参数。同时,采用数字图像相关(DIC)方法获得拉伸过程中的应变分布,并结合不同弹丸直径、冲击速度冲击后的剩余拉伸强度,进一步对比探究不同变量对冲击损伤的影响。研究结果表明弹丸直径是高速冲击损伤程度的主要影响因素。

关键词：陶瓷基复合材料高速冲击异物损伤剩余拉伸强度数字图像相关技术

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青藏公路沿线多年冻土活动层地温变化规律及影响因素研究

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青海大学学报 2024年第1期42卷 1-8页

作者：朱元涛任倩慧岳一凡聂婷婷青海大学土木水利学院青海西宁810016 黄河上游生态保护与高质量发展实验室青海西宁810016 水利部江河源区水生态治理与保护重点实验室青海西宁810016

为探究青藏公路沿线多年冻土活动层地温变化规律与影响因素,本文选取青藏公路沿线2个代表性地区(西大滩、五道梁)2013—2022年多年冻土活动层地温及气象数据,对多年冻土活动层地温的时空变化规律和4个主要影响因素(气温、比湿度、降水... 详细信息

为探究青藏公路沿线多年冻土活动层地温变化规律与影响因素,本文选取青藏公路沿线2个代表性地区(西大滩、五道梁)2013—2022年多年冻土活动层地温及气象数据,对多年冻土活动层地温的时空变化规律和4个主要影响因素(气温、比湿度、降水量、表层40cm土壤含水量展开研究。结果显示:青藏公路沿线多年冻土活动层地温在空间特征上表现为活动层地温波动幅度随着土壤深度的加深逐渐趋于平稳;在时间特征上表现为随着土壤深度的加深,气温对活动层地温产生的滞后天数逐渐增加。4个主要影响因素对多年冻土活动层地温影响的顺序为气温>比湿度>降水量>表层40cm土壤含水量,其中气温与比湿度对浅层活动层地温的贡献率最大,表层40cm土壤含水量贡献率最小。该结果可为青藏公路的病害分析和防治对策研究提供科学依据。

关键词：青藏高原多年冻土地温活动层

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全固态连续拉曼激光器谐振腔结构的设计分析

电子器件 2024年第4期47卷 968-974页

作者：周爱文孙雪纯王颖岳艺凡向柯赟沈君樊莉扬州大学物理科学与技术学院光电信息科学与工程系江苏扬州225009

谐振腔结构参数的选择对激光器性能提升尤为重要。采用ABCD传输矩阵法对连续波全固态拉曼激光器谐振腔的结构设计进行理论分析,详细研究了直线腔和折叠腔两种腔结构中晶体热透镜效应以及腔镜曲率半径、腔长等参数对腔内振荡激光腔模参... 详细信息

谐振腔结构参数的选择对激光器性能提升尤为重要。采用ABCD传输矩阵法对连续波全固态拉曼激光器谐振腔的结构设计进行理论分析,详细研究了直线腔和折叠腔两种腔结构中晶体热透镜效应以及腔镜曲率半径、腔长等参数对腔内振荡激光腔模参数的影响。在研究实现振荡基频激光与抽运光斑良好模式匹配的同时,减小拉曼介质中基频激光光斑尺寸,以获得高效率的拉曼转换,提高拉曼激光的输出功率和光束质量。所得研究结果将为优化设计拉曼激光器谐振腔的结构提供参考。

关键词：拉曼激光器全固态连续波谐振腔结构设计 ABCD传输矩阵

Feasible Synthesis of N,O-Bidentate Difluoroboron Chromophores through Direct Functionalization of Quinoxalin-2(1H)-ones with Ketones in One Shot

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Chinese Journal of Chemistry 2024年第13期42卷 1481-1486页

作者： Shuaichen Zhang Jing Zhang Xiang Ling yifan Zhao yue Ma Peng Sun State Key Laboratory for Quality Ensurance and Sustainable Use of Dao-di Herbs Artemisinin Research Center and Institute of Chinese Materia MedicaChina Academy of Chinese Medical SciencesBeijing 100700China Department of Pharmaceutics School of PharmacyChina Pharmaceutical UniversityState Key Laboratory of Natural MedicinesNanjingJiangsu 210009China

Organic difluoroboron complexes are a kind of potential platforms for a wide range of applications owing to their excellent photophysical ***,we have explored a simple and direct synthesis methodology for a library of N,O-bidentate difluoroboron complexes from quinoxalin-2(1H)-ones and ketones in one *** photophysical properties of the generated complexes were evaluated and the application potential of these compounds on subcellular imaging was also explored.

关键词： N,O-Bidentate difluoroboron Chromophores Quinoxalin-2(1H)-ones Ketones/Green chemistry Synthetic method C-CcouplingI Boron

Towards experimental studying the airborne sound insulation of light frame walls with staggered studs

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Science China(Technological Sciences) 2024年第7期67卷 2230-2243页

作者： ZHANG YuCai yue Kong XIE yifan CHENG XiangYu SHI XinLei WU Peng ZHAO Hui College of Civil Engineering Nanjing Tech UniversityNanjing 211800China Key Laboratory of Architectural Acoustic Environment of Anhui Higher Education Institutes Hefei 230601China Nanjing Gongda Construction Technology Co.Ltd. Nanjing 211800China

Light frame walls(LFWs) serve as common partition walls in prefabricated buildings due to their lightweight nature, costeffectiveness, energy efficiency, and adaptability for rapid on-site assembly. However, their acoustic insulation capability is hindered by issues such as sound bridges, resonance, and coincidence dips, resulting in inadequate sound insulation. This study aims to propose LFW designs with superior acoustic insulation suitable for practical engineering while meeting prevailing national standards. Nine full-scale LFW configurations were subjected to laboratory testing to evaluate the impact of staggered stud arrangements, stud types, and incorporation of compounded materials. The tests were performed between 100 and 5000 Hz,and the sound pressure level and reverberation time at 1/3 octave band were measured and used to calculate the weighted sound insulation index(Rw). Results demonstrated that the outlined design modifications significantly enhanced the sound insulation of the LFW. These modifications effectively mitigate the influence of sound bridges while addressing resonance and coincidence dips inherent in the wall system. Particularly noteworthy was the superior sound insulation achieved by staggered-stud LFWs with compounded materials, surpassing that of autoclaved lightweight concrete walls commonly used in prefabricated constructions despite having lesser thickness and surface density. Rwvalues increased from 43 to 54 dB compared to conventional LFWs, translating to a notable elevation in airborne sound insulation level from 4 to 7 as an internal separation component,meeting the requisite standards for most applications.

关键词： light frame wall staggered stud airborne sound insulation weighted sound insulation index

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Assessment on gas-polyethylene terephthalate solid interface partial discharge properties of C4F7N/CO_(2)gas mixture for eco-friendly gas insulating transformer

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High Voltage 2024年第1期9卷 35-45页

作者： Song Xiao yifan Wang Chenhua Ren Haoran Xia yue Zhao Jingzi Qin Xiaoxing Zhang Yi Luo Yi Li State Key Laboratory of Power Grid Environmental Protection School of Electrical Engineering and AutomationWuhan UniversityWuhanHubeiChina Beijing International S&T Cooperation Base for Plasma Science and Energy Conversion Institute of Electrical EngineeringChinese Academy of SciencesBeijingChina State Grid Anhui Electric Power Company Anhui Electric Power Research Institute HefeiAnhuiChina Hubei Engineering Research Center for Safety Monitoring of New Energy and Power Grid Equipment School of Electrical and Electronic EngineeringHubei University of TechnologyWuhanHubeiChina

The eco-friendly insulating gas perfluoroisobutyronitrile(C_(4)F_(7)N)is potentially used in gas-insulated transformers(GIT)to replace sulphur hexafluoride(SF_(6)).However,evaluation of the long-term insulation reliability and gas–solid interface discharge decomposition characteristics of the gas–solid film insulation structure in GIT is *** authors simulated the gas–solid film insulation structure in GIT and explored the interface partial discharge(PD)characteristics of C4F7N/CO_(2)gas mixture with polyethylene terephthalate(PET).The effect of gas pressure,mixing ratio on gas–solid interface gas decomposition,PET degradation was investigated,and the interaction mechanism was *** is found that the interface PD generated three degradation regions on a PET *** gas–solid interface reaction in the electrode contact region and the discharge development trace was significantly higher than that of halation *** content of gas decomposition products decreases with the increase of gas pressure and the PD intensity of SF6-PET is inferior to that of C_(4)F_(7)N/CO_(2)under the same *** results provide reference for the development and application of C_(4)F_(7)N/CO_(2)based GIT.

关键词： interface solid insulation

Work-function effect of Ti_(3)C_(2)/Fe-N-C inducing solid electrolyte interphase evolution for ultra-stable sodium storage

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Nano Research 2024年第8期17卷 7163-7173页

作者： Huicong Xia Lingxing Zan Hongliang Dong yifan Wei yue Yu Jinfu Shu Jia-Nan Zhang Chong-Xin Shan Key Laboratory of Advanced Energy Catalytic and Functional Material Preparation of Zhengzhou College of Materials Science and EngineeringZhengzhou UniversityZhengzhou 450001China Key Laboratory of Materials Physics of Ministry of Education School of Physics and MicroelectronicsZhengzhou UniversityZhengzhou 450001China Key Laboratory of Chemical Reaction Engineering of Shaanxi Province College of Chemistry and Chemical EngineeringYan’an UniversityYan’an 716000China Center for High Pressure Science and Technology Advanced Research PudongShanghai 201203China Key Laboratory of Advanced Energy Materials Chemistry(Ministry of Education) Nankai UniversityTianjin 300071China

In the quest to enhance the efficiency of sodium-ion batteries,the dynamics of solid electrolyte interphase(SEI)formation are of paramount *** SEI layer’s integrity is integral to the charge–discharge efficiency and the overall longevity of the ***,a novel two-dimensional Ti_(3)C_(2) fragments enmeshed on iron-nitrogen-carbon(Fe-N-C)nanosheets(Ti_(3)C_(2)/Fe-NC)has been *** electrode features a matrix which has been shown to expedite SEI layer formation through the facilitation of selective anion adsorption,thus augmenting battery *** functional theory calculation reveals that the SEI evolution energy of NaPF6 at the Ti_(3)C_(2)/Fe-N-C interface is 0.81 eV,significantly lower than the Ti_(3)C_(2)(1.23 eV).This process is driven by the electron transportation from Ti_(3)C_(2) to Fe-N-C substrate,facilitated by their work-function difference,leading to the formation of ferromagnetic Fe species,which possesses Fe 3d d_(xz)d_(z)2 orbitals and undergoes hybridization with theπandσorbitals of NaF,creating a key intermediate during *** process diminishes the antibonding energy and attenuates the orbital interaction with NaF,thus reducing the activation energy and improving the SEI formation reaction ***,it leads to the creation of multi-interface SEI characterized by high-throughput ion transport and an efficient reaction network.

关键词： Ti_(3)C_(2)/Fe-N-C heterostructure work-function electron interaction solid electrolyte interphase sodium storage

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基于位置敏感器件的杨氏模量测量

大学物理实验 2024年第2期37卷 65-69页

作者：岳伊帆胡亚华李俊成孟劲舟马玉彬张敏桂兆嘉兴南湖学院机电工程学院浙江嘉兴314001 嘉兴学院数据科学学院浙江嘉兴314001

利用位置敏感器件将经典的拉伸法测杨氏模量中金属丝的微小伸长量转换成电压信号变化,再由放大电路放大后,经过数据采集卡接入计算机进行实时数据采集,实现了杨氏模量的数字化测量。实验运用了现代科技测量的新器件、新技术,将硬件和软... 详细信息

利用位置敏感器件将经典的拉伸法测杨氏模量中金属丝的微小伸长量转换成电压信号变化,再由放大电路放大后,经过数据采集卡接入计算机进行实时数据采集,实现了杨氏模量的数字化测量。实验运用了现代科技测量的新器件、新技术,将硬件和软件在传统物理实验上进行了融合,实验数据处理设计了代表性的最小二乘法线性拟合和逐差法进行处理,测量结果可靠,可作为一个典型的综合性物理实验进行教学推广和使用。

关键词：位置敏感器件杨氏模量最小二乘法逐差法

Nitrogen and fluorine co-doped graphene for ultra-stable lithium metal anodes

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Nano Research 2024年第8期17卷 7212-7220页

作者： Pan Li yifan Liu Xujian Bao Jinghao Xie Zhao Li Hongcheng Li Qiang Ren Xiaomiao Feng yue Hu Yanwen Ma State Key Laboratory for Organic Electronics and Information Displays(KLOEID)and Jiangsu Key Laboratory for Biosensors Institute of Advanced Materials(IAM)Nanjing University of Posts and TelecommunicationsNanjing 210023China Key Laboratory of Carbon Materials of Zhejiang Province College of Chemistry and Materials EngineeringWenzhou UniversityWenzhou 325000China

The heteroatom doping strategies have been utilized to effectively improve the performance of the carbon-based hosts,such as graphene,for lithium(Li)metal in high energy density lithium metal ***,solely doped graphene hosts often need the assistance of other materials with either better lithiophilicity or electronic conductance to achieve smooth and efficient deposition of Li,which adds extra weight or ***,graphene co-doped by nitrogen and fluorine(NFG)is employed as a stable host for Li,where the N-doping provides lithiophilicity and electronic conductivity lacked by F-doping and the F-doping facilitates fast formation of solid electrolyte interphase(SEI)retarded by *** well regulation of Li plating/stripping and SEI formation is verified by quickly stabilized and small-magnitude voltage hysteresis,which stands out in Li hosts based on doped graphene and leads to excellent long-term cycling performance of NFG based electrodes.A voltage hysteresis of 20 mV is observed for more than 850 h in the symmetrical *** remarkable efficiency of lithium usage is confirmed by the highcapacity retention of a full cell paired with LiFePO_(4)(LFP),which exceeds 70%after 500 *** work presents an innovative perspective on the control of Li plating/stripping by simultaneously introducing two kinds of dopants into graphene and paving the way for exploring practical Li metal batteries.

关键词： Co-doped graphene lithium metal anode dendrite suppression lithiophilic skeleton solid electrolyte interphase(SEI)formation