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Journal of Wuhan University of Technology(Materials Science) 2022年第3期37卷 513-517页

作者： HUA Zhiting shan tongtong GENG Run ZHAO Qinglong Key Laboratory of Automobile Materials(Ministry of Education)and School of Materials Science and Engineering Jilin UniversityChangchun 130022China

The hot-plate rolling(HPR)process is adopted to achieve the optimal strength-ductility for the in-situ nano-TiC_(P)/Al-Mg-Si *** was no crack in the sheet by single pass of hot-plate rolling with a thickness reduction of 80%,while there were numerous cracks in the sheet by two passes of conventional hot rolling to achieve a total reduction of 50%.The microstructure and mechanical properties of the composites subjected to 80%thickness reduction of hot rolling at 540℃were investigated by tensile tests,scanning electron microscopy,and electron backscatter *** yield strength and ultimate tensile strength of in-situ nano-TiC_(P)/Al-Mg-Si composites after the hot-plate rolling process and T6 heat treatment increased significantly due to the dislocation strengthening and precipitation strengthening.

关键词： hot-plate rolling process aluminum matrix composites microstructure evolution mechanical property

Tuning the exciton binding energy of covalent organic frameworks for efficient photocatalysis

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Chinese Chemical Letters 2024年第2期35卷 577-583页

作者： Zhangjie Gu Zhen shan Yulan Wang Jinjian Wang tongtong Liu Xiaoming Li Zhiyang Yu Jian Su Gen Zhang Key Laboratory for Soft Chemistry and Functional Materials of Ministry of Education School of Chemistry and Chemical EngineeringNanjing University of Science and TechnologyNanjing 210094China State Key Laboratory of Photocatalysis on Energy and Environment College of ChemistryFuzhou UniversityFuzhou 350002China MIIT Key Laboratory of Advanced Display Material and Devices School of Materials Science and EngineeringNanjing University of Science and TechnologyNanjing 210094China Key Laboratory of Preclinical Study for New Drugs of Gansu Province School of Basic Medical SciencesLanzhou UniversityLanzhou 730000China

Owing to the large exciton binding energy(>100 meV)of most organic materials,the process of exciton dissociation into free electrons and holes is seriously hindered,which plays a key role in the photocatalytic *** this study,a series of chalcogen(S,Se)-substituted mesoporous covalent organic frameworks(COFs)have been synthesized for enhanced photocatalytic organic *** measurements indicate that the introduction of semi-metallic Se atom and the enlargement of conjugation degree can not only reduce the exciton binding energy accelerating the charge separation,but also reduce the band gap of *** a result,the COF-NUST-36 with the lowest exciton binding energy(39.5 meV)shows the highest photocatalytic performance for selective oxidation of amines(up to 98%*** 97.5%Sel.).This work provides a feasible method for designing COFs with high photocatalytic activity by adjusting exciton binding energy.

关键词： Covalent organic frameworks Exciton binding energy Atom substitution Extended conjugation Photocatalysis

Highly efficient optics/microwave beam splitter based on frequency selective surface

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Chinese Optics Letters 2024年第6期22卷 136-141页

作者： Qiao Sun Nianxi Xu Haigui Yang Dongzhi shan Yang Tang Xin Chen tongtong Wang Jinsong Gao Yu Cai Key Laboratory of Optical System Advanced Manufacturing Technology Changchun Institute of OpticsFine Mechanics and PhysicsChinese Academy of SciencesChangchun 130033China State Key Laboratory of Applied Optics Changchun Institute of OpticsFine Mechanics and PhysicsChinese Academy of SciencesChangchun 130033China University of Chinese Academy of Sciences Beijing 100049China Jilin Provincial Key Laboratory of Advanced Optoelectronic Equipment and Instrument Manufacturing Technology Changchun 130033China Unit 96951 of the People’s Liberation Army Beijing 100039China

The development of hybrid optics/microwave communication systems puts forward a new requirement for beam splitters to efficiently transmit microwave signals and simultaneously reflect optical signals. Owing to mechanical constraints, the physical thickness of beam splitters is of the order of tens of millimeters. The corresponding electrical thickness has the same order of magnitude as microwave wavelengths, and the resulting multi-beam interference effect significantly reduces the microwave transmittance, impacting the beam splitting *** study presents a new optics/microwave beam splitter based on the ability of the frequency selective surface(FSS) to shape the resonant curve. A beam splitter sample,whose physical thickness and substrate material are 20 mm and quartz glass, respectively, is designed, simulated, fabricated, and characterized to validate the feasibility of this strategy. The measured results show that the minimum microwave transmittance between 35 and 36.5 GHz with an incidence angle of 45° under TE polarization is 86.43%, and the mean value of the reflectance spectra from 450 to 900 nm and that from 7.7 to 10.5 μm both exceed 96%. This FSS-based optics/microwave beam splitter is expected to play a key role in hybrid optics/microwave communication systems.

关键词： beam splitter multi-beam interference frequency selective surface high transmission

Spontaneous mutations and mutational responses to penicillin treatment in the bacterial pathogen Streptococcus pneumoniae D39

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Marine Life Science & Technology 2024年第2期6卷 198-211页

作者： Wanyue Jiang tongtong Lin Jiao Pan Caitlyn ERivera Clayton Tincher Yaohai Wang Yu Zhang Xiang Gao Yan Wang Ho‑Ching T.Tsui Malcolm E.Winkler Michael Lynch Hongan Long Institute of Evolution and Marine Biodiversity KLMMEOcean University of ChinaQingdao 266003China Laboratory for Marine Biology and Biotechnology Laoshan LaboratoryQingdao 266237China Department of Biology Indiana UniversityBloomingtonIN 47405USA School of Mathematics Science Ocean University of ChinaQingdao 266000China State Key Laboratory of Microbial Technology Microbial Technology InstituteSchool of Life ScienceShandong UniversityQingdao 266237China Biodesign Center for Mechanisms of Evolution Arizona State UniversityTempeAZ 85281USA

Bacteria with functional DNA repair systems are expected to have low mutation rates due to strong natural selection for genomic ***,our study of the wild-type Streptococcus pneumoniae D39,a pathogen responsible for many common diseases,revealed a high spontaneous mutation rate of 0.02 per genome per cell division in mutation-accumulation(MA)*** rate is orders of magnitude higher than that of other non-mutator bacteria and is characterized by a high mutation bias in the A/T *** high mutation rate may have resulted from a reduction in the overall efficiency of selection,conferred by the tiny effective population size in *** line with this,*** D39 also exhibited the lowest DNA mismatch-repair(MMR)efficiency among *** with the antibiotic penicillin did not elevate the mutation rate,as penicillin did not induce DNA damage and *** lacks a stress response *** findings suggested that the MA results are applicable to within-host scenarios and provide insights into pathogen evolution.

关键词： Neutral evolution Mutation spectrum Antibiotics DNA mismatch repair Oxidative damage repair

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非蒸散型薄膜吸气剂的研究现状及应用进展

功能材料 2018年第5期49卷 5049-5055页

作者：单睿齐通通黎秉哲郭杰袁俊云南师范大学昆明650500 昆明物理研究所昆明650223

非蒸散型吸气剂薄膜是超高或极超高真空系统获得和维持真空条件的重要材料,近年来吸气剂广泛应用于MEMS真空封装领域。综述了非蒸散型吸气剂的材料体系、研究现状和工程应用,介绍国内外吸气剂薄膜的研究现状、存在的主要问题及发展趋势... 详细信息

非蒸散型吸气剂薄膜是超高或极超高真空系统获得和维持真空条件的重要材料,近年来吸气剂广泛应用于MEMS真空封装领域。综述了非蒸散型吸气剂的材料体系、研究现状和工程应用,介绍国内外吸气剂薄膜的研究现状、存在的主要问题及发展趋势。讨论了吸气剂在MEMS真空封装系统的工作原理,传统吸气剂在封装领域的挑战,薄膜吸气剂在封装系统遇到的问题和发展趋势。

关键词：非蒸散型吸气剂薄膜 Zr-Co系研究现状应用进展发展趋势

Phase formation,texture evolutions,and mechanical behaviors of Al0.5CoCr0.8FeNi2.5V0.2 high-entropy alloys upon cold rolling

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Progress in Natural Science:Materials International 2022年第2期32卷 196-205页

作者： tongtong Sun Weidong Song Feilong shan Kaikai Song Kun Zhang Chuanxiao Peng Honggang Sun Lina Hu School of Mechanical Electrical & Information Engineering Shandong University State Key Laboratory of Explosion Science and Technology Beijing Institute of Technology CAS Key Laboratory of Microgravity (National Microgravity Laboratory) Institute of Mechanics Chinese Academy of Sciences Key Laboratory for Liquid-Solid Structural Evolution & Processing of Materials (Ministry of Education) Shandong University

The cold rolling(CR) reduction dependence of microstructure evolutions and mechanical properties for Al0.5CoCr0.8FeNi2.5V0.2high-entropy alloy(HEA) were *** HEA remains FCC structures consisting of nanoscale ordered L12phase,confirming the phase formation *** increasing CR reduction,the textures transform from random ones to FCC rolling ones accompanied by dense slip bands and deformation *** a 50% CR reduction,the deformation textures started to become evident and were governed by typical {111}F,{110}Goss and {112}Cu texture *** the CR reduction approached 90%,the deformation textures mainly contained the {110}A,{114}X,and {112}Cu texture *** a result,both Vickers hardness and ultimate strength increased,but the ductility decreased *** enhanced strength should be attributed to the anisotropy and work hardening behavior from *** plastic deformation for the samples under low CR reductions was dominated by deformation twins and slip ***,under high CR reductions,the textures severely impeded the further propagation of pre-existing slip bands,leading to the rapid decrease of ***,the CR reduction should be carefully designed before optimal heat treatments to enhance the strength and ductility synergy.

关键词： High-entropy alloys Cold rolling Texture Mechanical property Ductility

基于主成分分析和偏最小二乘法的蒸煮大豆食味品质评价

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中国食品学报 2019年第10期19卷 265-277页

作者：石彦国单彤彤曾剑华刘琳琳朱秀清哈尔滨商业大学食品工程学院黑龙江省谷物食品与谷物资源综合加工重点实验室哈尔滨150076 黑龙江省绿色食品科学研究院哈尔滨150028

通过建立主成分分析结合偏最小二乘法(PLS)评价蒸煮大豆食味品质。以黑龙江45个大豆品种的理化指标、浸泡后的吸水率和膨胀率为自变量,以蒸煮后的硬度、咀嚼性和感官评分为因变量,应用偏最小二乘法判别模型中各变量的相关系数和变量投... 详细信息

通过建立主成分分析结合偏最小二乘法(PLS)评价蒸煮大豆食味品质。以黑龙江45个大豆品种的理化指标、浸泡后的吸水率和膨胀率为自变量,以蒸煮后的硬度、咀嚼性和感官评分为因变量,应用偏最小二乘法判别模型中各变量的相关系数和变量投影重要性,筛选影响蒸煮大豆食味品质的主要因素并进行主成分分析。结果表明:通过PLS筛选出大豆钙含量、伴大豆球蛋白(7S球蛋白)、可溶性糖含量和膨胀率对蒸煮后大豆质构特性有主要影响。主成分分析检测得到4个主成分,累计贡献率达73.374%,可较好地反映蒸煮大豆食味品质信息。根据各主成分的贡献率得出蒸煮大豆的硬度、咀嚼性及7S球蛋白、11S/7S、钙含量等为蒸煮大豆食味品质的主要影响因子。利用主成分综合得分模型对不同品种的蒸煮大豆食味品质进行综合评分,筛选出5种适宜蒸煮加工的大豆品种,即:黑农85、合丰55、JD149、绥农42和东农251。

关键词：蒸煮大豆食味品质品种筛选主成分分析偏最小二乘法

Improved methodology for efficient establishment of the myocardial ischemia-reperfusion model in pigs through the median thoracic incision

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The Journal of Biomedical Research 2023年第4期37卷 302-312页

作者： Liuhua Zhou Jiateng Sun tongtong Yang Sibo Wang Tiankai shan Lingfeng Gu Jiawen Chen Tianwen Wei Di Zhao Chong Du Yulin Bao Hao Wang Xiaohu Lu Haoliang Sun Meng Lv Di Yang Liansheng Wang Department of Cardiology the First Affiliated Hospital of Nanjing Medical UniversityNanjingJiangsu 210029China Department of Cardiac Surgery the First Affiliated Hospital of Nanjing Medical UniversityNanjingJiangsu 210029China Medical Experimental Animal Center Nanjing Medical UniversityNanjingJiangsu 210029China

To investigate the feasibility and effectiveness of establishing porcine ischemia-reperfusion models by ligating the left anterior descending(LAD)coronary artery,we first randomly divided 16 male Bama pigs into a sham group and a model *** anesthesia,we separated the arteries and ***,we rapidly located the LAD coronary artery at the beginning of its first diagonal branch through a mid-chest ***,we loosened and released the ligation line after five minutes of ***,we ligated the LAD coronary artery in situ two minutes later and loosened the ligature 60 min after *** with the sham group,electrocardiogram showed multiple continuous lead ST-segment elevations,and ultrasound cardiogram showed significantly lower ejection fraction and left ventricular fractional shortening at one hour and seven days post-operation in the model ***-four hours after the operation,cardiac troponin T and creatine kinase-MB isoenzyme levels significantly increased in the model group,compared with the sham *** and eosin staining showed the presence of many inflammatory cells infiltrating the interstitium of the myocardium in the model group but not in the sham *** staining revealed a significant increase in infarct size in the ischemia/reperfusion *** eight pigs in the model group recovered with normal sinus heart rates,and the survival rate was 100%.In conclusion,the method can provide an accurate and stable large animal model for preclinical research on ischemia/reperfusion with a high success rate and homogeneity of the myocardial infarction area.

关键词： coronary artery ligation myocardial ischemia-reperfusion injury Bama pig animal model

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跨文化空间中的网络文学经典化

江西师范大学学报（哲学社会科学版） 2022年第4期55卷 95-100页

作者：侯瞳瞳鄢楚茜单世联上海交通大学媒体与传播学院上海200240 南昌师范学院美术学院江西南昌330032

中国网络文学最根本的特质,是“网络性”与“跨文化性”的重叠。这种特质使得网络文学能够打破地域与文化疆界的藩篱,构筑了一个独一无二的跨文化空间。网络文学跨文化空间中的经典形成机制,包含以作品艺术价值的可共鸣性和跨媒介阐释... 详细信息

中国网络文学最根本的特质,是“网络性”与“跨文化性”的重叠。这种特质使得网络文学能够打破地域与文化疆界的藩篱,构筑了一个独一无二的跨文化空间。网络文学跨文化空间中的经典形成机制,包含以作品艺术价值的可共鸣性和跨媒介阐释空间的可延展性为代表的内部因素、以学术界话语的倾斜与变迁为代表的外部因素、以跨文化读者的能动性参与为代表的中介因素三个方面。对网络文学经典性的研判,应当从空间和时间两个维度来把握。跨文化空间中的网络文学经典传播探索,则可以从基本伦理、话语模式、文本策略三个层面展开。

关键词：网络文学跨文化空间经典化

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支持我国信息技术课程评价体系构建的计算思维描述框架设计

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电化教育研究 2022年第6期43卷 115-121页

作者：冯友梅王珊王昕怡周彤彤天津师范大学教育学部天津300387

信息技术课程计算思维评价体系的构建需要以系统的评价目标体系为基础,但此评价目标体系很难形成。直接原因为:作为评价目标确定的重要依据,既有计算思维描述框架中“过程”维度的要素不能进行多层粒度细化。深层原因则为:认知心理学对... 详细信息

信息技术课程计算思维评价体系的构建需要以系统的评价目标体系为基础,但此评价目标体系很难形成。直接原因为:作为评价目标确定的重要依据,既有计算思维描述框架中“过程”维度的要素不能进行多层粒度细化。深层原因则为:认知心理学对“思维过程”与“思维内容”的人为割裂。鉴于此,为从根本上突破计算思维评价困境,文章以“知识与思维内在统一”为基本立场,将“计算思维过程”与“计算思维内容”还原为完整的动态计算思维,在此基础上寻找与动态计算思维内在一致的静态知识结构。经过层层剥离、转换,最终形成包含“计算概念”与“计算策略”两个维度的计算思维二维描述框架。该描述框架中各维度的要素集合亦是具有信息技术学科本质特征的核心知识集,其不仅可以支持从宏观到微观的多层计算思维评价目标体系以及评价体系的构建,而且可以为信息技术课程“单元群—单元—课”整体教学设计提供必要抓手。

关键词：计算思维计算策略描述框架信息技术课程评价体系