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Journal of Materials Science & Technology 2022年第18期113卷 71-81页

作者： zhuguang Nie Yang Feng qing zhu Ying xia Liping Luo Lan Ma Jie Su xingman Hu Rumin Wang Shuhua Qi School of Chemistry and Chemical Engineering Northwestern Polytechnical UniversityXi’an 710072China

High-efficiency microwave absorbers with broadband absorption are strongly desired for electromag-netic ***,we successfully synthesized a hybrid microwave absorbing material with two-dimensional layered structure,which consisted of expanded graphite(Eg)and boron nitride(BN).The introduction of BN is to regulate the conductivity of Eg and also to improve the thermal stability of the composite *** ultrathin BN nano-sheets were uniformly wrapped on the Eg sheets via chemi-cal vapor *** to the dielectric loss and conductive loss,the as-prepared hybrid material exhibited high performance for microwave *** effective absorbing bandwidth(reflection loss valuegHz with the thickness of 2.4 mm in the frequency range of 5.75-6.98 gHz and 9.86-18 *** the minimum reflection loss was-51.58 dB at the thickness of 3 *** excellent performance of microwave absorption was attributed to the dielectric loss,interfacial polarization loss and optimized impedance ***,compared to pure Eg,the thermal de-composition temperature of Eg/BN composite materials had increased by about 100℃which was up to 714℃.Taking the advantages of high thermal stability of BN as well as the fine microwave absorbability of Eg,the Eg/BN composites would be applied in high-temperature microwave absorbing fields.

关键词： Layered-structure Expanded graphite Boron nitride Microwave absorption

多媒体与翻转课堂联合教学模式在心血管内科临床见习教学中的应用研究

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医学教育研究与实践 2024年第3期32卷 355-358页

作者：林琳刘伯恒李青朱文静王小芳西安交通大学第二附属医院心血管内科陕西西安710004 西安交通大学医学部临床医学系陕西西安710061

目的探讨多媒体与翻转课堂联合教学模式在心血管内科临床见习带教中的应用效果。方法选取2022—2023年西安交通大学第二附属医院心血管内科接收的临床见习生共计100名作为研究对象,随机分为实验组与对照组,其中对照组接受传统见习带教模... 详细信息

目的探讨多媒体与翻转课堂联合教学模式在心血管内科临床见习带教中的应用效果。方法选取2022—2023年西安交通大学第二附属医院心血管内科接收的临床见习生共计100名作为研究对象,随机分为实验组与对照组,其中对照组接受传统见习带教模式,实验组接受多媒体联合翻转课堂见习带教模式。选取出科考试成绩、综合能力水平、满意度作为观察指标,P<0.05表示差异具有统计学意义。结果与对照组比较,实验组的各项观察指标提示该模式的教学效果更加理想,差异具有统计学意义(P<0.05)。结论在心血管内科临床见习带教中应用多媒体联合翻转课堂教学模式,相比传统见习带教模式更有助于提升学生的考试成绩、综合能力及见习体验。

关键词：心血管内科临床见习翻转课堂多媒体技术

Supramolecular Template-Assisted Catalytic[2+2]Photocycloaddition in Homogeneous Solution

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CCS Chemistry 2023年第3期5卷 633-640页

作者： Fang Wang Sha bai qing-Wen zhu Zi-Hang Wei Ying-Feng Han Key Laboratory of Synthetic and Natural Functional Molecule of the Ministry of Education Xi’an Key Laboratory of Functional Supramolecular Structure and MaterialsCollege of Chemistry and Materials ScienceNorthwest UniversityXi’an 710127

Supramolecular interactions can help recognize and organize substrates around an enzyme’s active sites and subsequently assemble a new molecule in a certain *** by nature’s control of reactions,in this work we designed a template catalyst equipped with ditopic Au(I)–N-heterocyclic carbene(NHC)functional sites that direct olefin substrates into reactive geometries via collaboration of coordination-driven ***,this catalyst enables the realization of catalytic[2+2]photocycloadditions with as low as 2 mol%catalyst loading in homogeneous solution and the delivery of a series of cyclobutane derivatives with excellent conversions and *** success of gram-scale reactions further demonstrates the feasibility of this strategy,which lays a solid foundation for the large-scale preparation of cyclobutane derivatives in the future.

关键词： N-heterocyclic carbene supramolecular catalysis template synthesis photocycloaddition self-assembly

Amyloid and tau positive mild cognitive impairment:clinical and biomarker characteristics of dementia progression

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Chinese Medical Journal 2021年第14期134卷 1709-1719页

作者： Hong-Chun Wei Bing Li Kok Pin Ng qing-xi Fu Sheng-Jie Dong Mao-Wen ba Min Kong Department of Neurology The Affiliated Yantai Yuhuangding Hospital of Qingdao UniversityYantaiShandong 264000China Department of Neurology National Neuroscience InstituteSingapore 119077Singapore Department of Neurology Linyi People’s HospitalLinyiShandong 276000China Department of Orthopedics Yantaishan HospitalYantaiShandong 264003China Department of Neurology Yantaishan HospitalYantaiShandong 264003China

background:According to the amyloid,tau,neurodegeneration research framework classification,amyloid and tau positive(A+T+)mild cognitive impairment(MCI)individuals are defined as prodromal Alzheimer *** study was designed to compare the clinical and biomarker features between A+T+MCI individuals who progressed to progressive MCI(pMCI)and those who remained stable MCI(sMCI),and to identify relevant baseline clinical biomarker and features that could be used to predict progression to dementia within 2 ***:We stratified 197 A+T+MCI individuals into pMCI(n=64)and sMCI(n=133)over 2 *** and cognitive assessment scores,cerebrospinal fluid(CSF),and neuroimaging biomarkers(18F-florbetapir positron emission tomography mean standardized uptake value ratios[SUVR]and structural magnetic resonance imaging[MRI])were compared between pMCI and sMCI at baseline,12-and 24-month *** regression models then were used to evaluate clinical baseline and biomarker features that predicted dementia progression in A+T+***:pMCI individuals had higher mean 18F-florbetapir SUVR,CSF total-tau(t-tau),and p-tau181P than those in sMCI *** individuals performed poorer in cognitive assessments,both global and domain specific(memory,executive,language,attention,and visuospatial skills)than *** baseline,there were significant differences in regions of interest of structural MRI between the two groups,including bilateral amygdala,hippocampus and entorhinal,bilateral inferior lateral ventricle,left superior and middle temporal,left posterior and caudal anterior cingulate(Pbaseline CSF t-tau levels and cognitive scores of Montreal cognitive assessment,functional assessment questionnaire,and everyday cognition by the patient’s study partner language domain could predict progression to dementia in A+T+MCI within 2 ***:In future clinical trials,specific CSF and cognitive measures that predict dementia progression in A

关键词： Alzheimer disease Mild cognitive impairment Amyloid and tau positive mild cognitive impairment Dementia

IPS observation system for the Miyun 50m radio telescope and its commissioning observation

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Research in Astronomy and Astrophysics 2012年第7期12卷 857-864页

作者： xin-Ying zhu xi-Zhen Zhang Hong-Bo Zhang De-qing Kong Hui-Peng Qu National Astronomical Observatories Chinese Academy of Sciences Beijing 100012 China Beijing Institute of Tracking and Telecommunications Technology Beijing 100094 China

ground-based observation of Interplanetary Scintillation （IPS） is an impor- tant approach for monitoring solar wind. A ground-based IPS observation system has been newly implemented on a 50 m radio telescope at Miyun station, managed by the National Astronomical Observatories, Chinese Academy of Sciences. This observa- tion system has been constructed for the purpose of observing solar wind speed and the associated scintillation index by using the normalized cross-spectrum of a simul- taneous dual-frequency IPS measurement. The system consists of a universal dual- frequency front-end and a dual-channel multi-function back-end specially designed for IPS. After careful calibration and testing, IPS observations on source 3C 273B and 3C 279 have been successfully carried out. The preliminary observation results show that this newly-developed observation system is capable of performing IPS observa- tion. The system＇s sensitivity for IPS observation can reach over 0.3 Jy in terms of an IPS polarization correlator with 4 MHz bandwidth and 2 s integration time.

关键词： instrument - interplanetary scintillation -- telescope -- radio astron-omy

Oxidative Damage to Lung Tissue and Peripheral Blood in Endotracheal PM_(2.5)-treated Rats

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Biomedical and Environmental Sciences 2009年第3期22卷 223-228页

作者： zhi-qing LIN zhu-gE xi DAN-FENg YANg Fu-HUAN chaO HUA-SHAN ZHANg WEI ZHANg HUANg-LIANg LIU ZAI-MINg YANg RU-baO SUN Institute of Health and Environmental Medicine Tianjin 300050 China State Environmental Protection Key Laboratory of Urban Ambient Air Particulate Matter Pollution Prevention and Control Tianjin 300071 China

Objective To investigate the oxidative damage to lung tissue and peripherial blood in PM2.5-treated rats. Methods PM2.5 samples were collected using an auto-sampling instrument in summer and winter. Treated samples were endotracheally instilled into rats. Activity of reduced glutathione peroxidase （gSH-Px） and concentration of malondialdehyde （MDA） were used as oxidative damage biomarkers of lung tissue and peripheral blood detected with the biochemical method. DNA migration length （μm） and rate of tail were used as DNA damage biomarkers of lung tissue and peripheral blood detected with the biochemical method. Results The activity of gSH-Px and the concentration of MDA in lung tissue significantly decreased after exposure to PM2.5 for 7-14 days. In peripheral blood, the concentration of MDA decreased, but the activity of gSH-Px increased 7 and 14 days after experiments. The two indicators had a dose-effect relation and similar cha.ging tendency in lung tissue and peripheral blood. The DNA migration length （μm） and rate of tail in lung tissue and peripheral blood significantly increased 7 and 14 days after exposure to PM2.5. The two indicators had a dose-effect relation and similar cha.ging tendency in lung tissue and peripheral blood. Conclusion PM2.5 has a definite oxidative effect on lung tissue and peripheral blood. The activity of gSH-Px and the concentration of MDA are valuable biomarkers of oxidative lung tissue damage induced by PM2.5. The DNA migration length （μm） and rate of tail are simple and valuable biomarkers of PM2 5-induced DNA damage in lung tissues and peripheral blood. The degree of DNA damage in peripheral blood can predict the degree of DNA damage in lung tissue.

关键词： PM2.5 Endotracheal instillation Oxidative damage Oxidative DNA damage Biomarker DNA repair

扬子地块西缘中元古代晚期辉长岩成因及地质意义:来自锆石U-Pb-Hf同位素和全岩地球化学的约束

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西北大学学报（自然科学版） 2024年第4期54卷 696-714页

作者：薛文斌赖绍聪朱毓秦江锋朱韧之刘敏杨航西北大学地质学系/大陆动力学国家重点实验室陕西西安710069

对扬子地块西缘锦川地区辉长岩进行系统的锆石U-Pb-Hf同位素、全岩主微量元素和Sr-Nd同位素分析,旨在探讨其岩石成因及地质意义。年代学分析结果表明,锦川辉长岩的锆石U-Pb年龄为(1041.1±1.1)Ma。全岩地球化学特征显示,锦川辉长岩具有... 详细信息

对扬子地块西缘锦川地区辉长岩进行系统的锆石U-Pb-Hf同位素、全岩主微量元素和Sr-Nd同位素分析,旨在探讨其岩石成因及地质意义。年代学分析结果表明,锦川辉长岩的锆石U-Pb年龄为(1041.1±1.1)Ma。全岩地球化学特征显示,锦川辉长岩具有较低的SiO_(2)(50.26%~51.16%)、CaO(6.59%~7.64%)、K_(2)O(1.22%~1.96%)质量分数以及较高的Al_(2)O_(3)(16.38%~17.15%)和TiO_(2)(2.61%~2.80%)质量分数,属于低钾拉斑玄武质岩石系列。岩石总体上相对富集轻稀土元素和大离子亲石元素(如ba、Sr),亏损重稀土元素和高场强元素(如Nb、Ta和Th),并且显示弱的Eu异常(δEu=0.99~1.11)。同时,锦川辉长岩具有低的全岩εNd(t)值(-3.61~-2.75)和正的锆石εHf(t)值(+1.62~+7.58)。上述特征表明,锦川辉长岩应起源于已保存在岩石圈地幔中的先期(中元古代中期)俯冲流体交代过的富集地幔源区。结合扬子地块西缘同期广泛发育的A型花岗岩和板内玄武质岩浆作用,认为锦川辉长岩应形成于被动大陆边缘背景下的陆内裂谷环境,代表了Rodinia超大陆在中元古代晚期局部拉张构造体制下的岩浆响应。

关键词：扬子地块西缘中元古代晚期辉长岩岩石成因地质意义

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Subsurface macro-inclusions and solidified hook character in aluminum-killed deep-drawing steel slabs

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International Journal of Minerals,Metallurgy and Materials 2014年第6期21卷 531-543页

作者： xiao-xuan Deng Lin-ping Li xin-hua Wang Yun-qing Ji Chen-xi Ji guo-sen zhu School of Metallurgical and Ecological Engineering University of Science and Technology Beijing Shougang Research Institute of Technology Shougang Group

Subsurface macro-inclusions and hooks are detrimental to the surface quality of deep-drawing steel sheets. However, little is known about the relationship between macro-inclusions and hooks. Thus, in this work, two ultralow carbon （ULC） steel slabs and two low carbon （LC） aluminum-killed steel slabs were sampled to study the relationship between hooks and subsurface macro-inclusions, which were detected on the cross-sections of steel samples with an area of 56058 mm2 using an automated scanning electron microscopy/energy-disper-sive X-ray spectroscopy system. Results show that subsurface inclusions larger than 200 μm were almost entrapped by hook structures, whereas the location of other inclusions smaller than 200μm had no obvious dependence on the location of solidified hooks. Furthermore, the number density （ND） of subsurface inclusions larger than 200μm decreased from 0.02 to 0 cm-2 in ULC steel as the mean hook depth decreased from 1.57 to 1.01 mm. Similar trends were also observed in LC steel. In addition, the detected inclusions larger than 200μm were concentrated in the region near the slab center （3/8 width-5/8 width）, where hook depths were also larger than those at any other locations. Therefore, minimizing the hook depth is an effective way to reduce inclusion-induced sliver defects in deep-drawing steels.

关键词： low carbon steel aluminum-killed steel steel sheet deep drawing inclusions hooks

Boosting electrocatalytic selectivity in carbon dioxide reduction:The fundamental role of dispersing gold nanoparticles on silicon nanowires

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Chinese Chemical Letters 2022年第9期33卷 4380-4384页

作者： Fan Liao xing Fan Huixian Shi qing Li Mengjie Ma Wenxiang zhu Haiping Lin Youyong Li Mingwang Shao Institute of Functional Nano&Soft Materials(FUNSOM) Jiangsu Key Laboratory for Carbon-Based Functional Materials&DevicesSoochow UniversitySuzhou 215123China School of Physics and Information Technology Shaanxi Normal UniversityXi'an 710062China

Carbon dioxide electrochemical reduction(CO_(2)RR)has been recognized as an efficient way to mitigate CO_(2)emissions and alleviate the pressure on global warming and associated environmental ***(Au)is reported as stable and active electrocatalysts to convert CO_(2)to CO at low overpotential due to its moderate adsorption strength of^(*)COOH and^(*)*** request for improved catalytic performance,however,is motivated by current unsatisfied catalytic selectivity because of the side hydrogen evolution *** this context,the design of Au based binary catalysts that can boost CO selectivity is of great *** the present work,we report that Au nanoparticles can be feasibly dispersed and anchored on silicon nanowires to form Au-Si binary *** Au-Si may stably drive CO_(2)RR with a CO Faraday efficiency of 95.6%at−0.6 V *** in 0.5 mol/L KHCO_(3)*** selectivity outperforms Au particles by up to 61%.Controlled experiments illustrate that such catalytic enhancement can chiefly be ascribed to electronic effects of binary *** calculations reveal that spontaneously produced silicon oxide may not only inhibit hydrogen evolution reaction,but also stabilize the key intermediate^(*)COOH in CO formation.

关键词： gold nanoparticles Silicon nanowires Electrocatalysis Carbon dioxide reduction Noble metals

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单轴晶体中产生的高纯度纵向针形磁化场

物理学报 2022年第14期71卷 290-297页

作者：许琳茜朱榕琪朱竹青贡丽萍顾兵南京师范大学物理科学与技术学院江苏省光电子技术重点实验室南京210023 南京师范大学计算机与电子信息学院南京210023 上海工程技术大学数理与统计学院上海201620 东南大学先进光子学中心南京210096 山东师范大学光场调控与应用协同创新中心济南250358

基于理查德-沃尔夫矢量衍射理论和逆法拉第效应,提出一种在单轴晶体中产生高纯度纵向针形磁化场的方法.该方法通过电偶极子对数N及其阵列多参数调控,利用单轴晶体中的电偶极子反向辐射构建出优化的入瞳光场,再正向紧聚焦获得所需目标磁... 详细信息

基于理查德-沃尔夫矢量衍射理论和逆法拉第效应,提出一种在单轴晶体中产生高纯度纵向针形磁化场的方法.该方法通过电偶极子对数N及其阵列多参数调控,利用单轴晶体中的电偶极子反向辐射构建出优化的入瞳光场,再正向紧聚焦获得所需目标磁化场.模拟结果表明:当N=1时,单轴晶体中产生的磁化场比在同性介质中焦深长度增加近1.4倍,横向分辨率提高5%.当N=2和N=3时,单轴晶体中获得的纵向针形磁化场随着电偶极子对数增加,轴向焦深增加了10%,横向分辨率提高了18%.随着磁化场轮廓表面值从0.1变化到1,针形磁化场的纯度逐渐增大到1.尤其当N=2、轮廓表面值为0.1时,磁化场纯度高达95%.研究结果为在各向异性介质中生成更高纯度、针长更长的纵向磁化场提供了可行性方案,也为全光磁记录、原子捕获和光刻等实际应用中入瞳光场的优化选取提供了理论指导.

关键词：电偶极子逆法拉第效应紧聚焦单轴晶体

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