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Microstructure and mechanical properties of liquid phase sintered silicon carbide composites

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2010年第10期11卷 766-770页

作者： Jing-mei MA Feng ye Yan-ge CAO chun-feng LIU Hai-jiao ZHANG School of Materials Science and Engineering Harbin Institute of Technology Harbin 150001 China Air China Corporation Limited Engineering and Technology Branch Beijing 101312 China

Silicon carbide (SiC) composites were prepared by hot-press sintering from α-SiC starting powders with BaAl2Si2O8 (BAS). The effects of additives on densification, microstructure, flexural strength, and fracture behavior of the liquid phase sintered (LPS) SiC composites were investigated. The results show that the served BAS effectively promotes the densification of SiC composites. The flexural strength and fracture toughness of the SiC composites can reach a maximum value of 454 MPa and 5.1 MPa·m1/2, respectively, for 40% (w/w) BAS/SiC composites. SiC grain pullout, crack deflection, and crack bridging were main toughening mechanisms for the sintered composites.

关键词： Silicon carbide (SiC) BaAl2Si2O8 (BAS) Liquid phase sintered (LPS) Mechanical properties

Broadband Acoustic Transmission Enhancement through a Structured Stiff Plate with Locally Resonant Elements

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Chinese Physics Letters 2012年第11期29卷 123-126页

作者： LI Yong LIANG Bin ZOU Xin-ye CHENG Jian-chun Key Laboratory of Modern Acoustics MOEInstitute of AcousticsDepartment of PhysicsNanjing UniversityNanjing 210093 State Key Laboratory of Acoustics Chinese Academy of SciencesBeijing 100190

Broadband acoustic transmission enhancement(ATE)is realized for a periodically structured stiff plate without any opening that is conventionally thought to be only capable of supporting narrowband ATE,by introducing locally resonant(LR)*** exotic phenomenon is interpreted by analyzing the vibration pattern of the structure-induced LR modes,and is well modeled by a simple"spring-mass"system which reveals the contribution of the LR effect to the important broadband *** findings should help to better understand the physical mechanism of ATE and may have potential impact on ultrasonic applications such as broadband acoustic filters or compact acoustic devices in subwavelength scale.

关键词： Locally resonant stiff

Rearranged diterpenoids from the seeds of Caesalpinia sappan

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Chinese Chemical Letters 2016年第12期27卷 1751-1754页

作者： Fang Xiao chun-Ping Tang Chang-Qiang Ke Sheng Yao Yang ye State Key Laboratory of Drug Research & Natural Products Chemistry Department Shanghai Institute of Materia Medica Chinese Academy of Sciences Shanghai 201203 China University of Chinese Academy of Sciences Beijing 100049 China School of Life Science and Technology Shanghai Tech University Shanghai 201210 China

Two new rearranged diterpenoids, tomocinol C （1） and spirocaesalmin C （2） were isolated from the seeds of Caesalpinia sappan. Their structures were elucidated based on comprehensive analysis of spectroscopic data,... 详细信息

关键词： Diterpenoid Tomocinol C Spirocaesalmin C Caesalpinia sappan Absolute configuration X-ray crystallography

Two New Oleanane Saponins from Anemone anhuiensis

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Chinese Chemical Letters 2000年第8期11卷 697-700页

作者： Qing Wen ZHANG Wen Cai ye chun Tao CHE Shou Xun ZHAO Department of Phytochemistry China Pharmaceutical UniversityNanjing 210009 School of Chinese Medicine The Chinese University of Hong KongHong Kong

Two new oleanane triterpene saponins, named as anhuienside C (1) and D (2), were isolated from the rhizomes of Anemone anhuiensis (Ranunculaceae). The structures of the new compounds were elucidated as 3-O-alpha-L-rhamnopyranosyl (1-->2)-beta-D-xylopyranosyl oleanolic acid 28-O-beta-D-glucopyranosyl (1-->6)-beta-D-glucopyranosyl ester (1) and 3-O-beta-D-xylopyranosyl oleanolic acid 28-O-alpha-L-rhamnopyranosyl (1-->4)-beta-D-glucopyranosyl (1-->6)-beta-D-glucopyranosyl ester (2), respectively.

关键词： anemone anhuiensis ranunculaceae anhuiensides C and D oleanane saponin

A Case Report of Radiofrequency Ablation of Typical Atrial Flutter Combined with Atrial Tachycardia

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Cardiovascular Innovations and Applications 2021年第4期6卷 113-116页

作者： Chen chun-hui Ning Li-ye Cardiovascular Medicine Department Dongguan Kanghua HospitalDongguan 523000China

A 63-year-old female patient with a history of pulmonary heart disease underwent radiofrequency ablation because of a persistent atrial fl *** mapping with the carto3 system confi rmed atrial fl utter counterclockwise reentry around the tricuspid *** ablation of the cavo-tricuspid isthmus line to bi-directional block was ***,tachycardia with the same cycle length was induced *** remapping,the tachycardia was confi rmed to be focal atrial tachycardia located in the crista *** ablation,the tachycardia was terminated and could not be induced again.

关键词： Atrial flutter atrial tachycardia radiofrequency ablation

Antioxidant and anti-inflammatory agents in chronic liver diseases:Molecular mechanisms and therapy

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World Journal of Hepatology 2023年第2期15卷 180-200页

作者： chun-ye Zhang Shuai Liu Ming Yang Christopher S.Bond Life Sciences Center University of MissouriColumbiaMO 65211United States The First Affiliated Hospital Zhejiang UniversityHangzhou 310006Zhejiang ProvinceChina Department of Surgery University of MissouriColumbiaMO 65211United States

Chronic liver disease(CLD)is a continuous process that causes a reduction of liver function lasting more than six *** includes alcoholic liver disease(ALD),non-alcoholic fatty liver disease(NAFLD),chronic viral infection,and autoimmune hepatitis,which can lead to liver fibrosis,cirrhosis,and *** inflammation and oxidative stress are commonly associated with the development and progression of *** signaling pathways such as AMPactivated protein kinase(AMPK),C-Jun N-terminal kinase,and peroxisome proliferator-activated receptors(PPARs)are implicated in the pathogenesis of ***,antioxidant and anti-inflammatory agents from natural products are new potent therapies for ALD,NAFLD,and hepatocellular carcinoma(HCC).In this review,we summarize some powerful products that can be potential applied in all the stages of CLD,from ALD/NAFLD to *** selected agents such asβ-sitosterol,curcumin,genistein,and silymarin can regulate the activation of several important molecules,including AMPK,Farnesoid X receptor,nuclear factor erythroid 2-related factor-2,PPARs,phosphatidylinositol-3-kinase,and lysyl oxidase-like *** addition,clinical trials are undergoing to evaluate their efficacy and safety.

关键词： Chronic liver disease Alcoholic liver disease Non-alcoholic fatty liver disease Hepatocellular carcinoma Natural products Inflammation Oxidative stress Treatment Clinical trials

Effect of Screw-Dislocation on Electrical Properties of Spiral-Type Bi2Se3 Nanoplates

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Chinese Journal of Chemical Physics 2016年第6期29卷 687-692,I0001页

作者： Yu-kun Wu A-wei Zhuang chun-miao ye Jie Zeng Nan Pan Xiao-ping Wang HefeiNationalLaboratoryforPhysicalSciencesattheMicroscaleandDepartmentofPhysics UniversityofScienceandTechnologyofChinaHefei230025China

We systematically investigated the electrical nanoplates through field effect transistor and properties of spiral-type and smooth Bi2Se3 conductive atomic force microscopy （CAFM） measurement. It is observed that both nanoplates possess high conductivity and show metallic-like behavior. Compared to the smooth nanoplate, the spiral-type one exhibits the higher carrier concentration and lower mobility. CAFM characterization reveals that the conductance at the screw-dislocation edge is even higher than that on the terrace, implying that the dislocation can supply excess carriers to compensate the low mobility and achieve high conductivity. The unique structure and electrical properties make the spiral-type Bi2 Se3 nanoplates a good candidate for catalysts and gas sensors.

关键词： Bi2Se3 nanoplates Screw-dislocation Electrical properties Field effect tran-sistor Conductive atomic force microscopy

Potential effects of the nursing work environment on the work-family conflict in operating room nurses

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World Journal of Clinical Cases 2021年第26期9卷 7738-7749页

作者： chun-Mei Fu Jie Ou Xiao-Mei Chen Mei-ye Wang Department of Ophthalmology Hainan West Central HospitalDanzhou 571700Hainan ProvinceChina Department of Critical Care Medicine Hainan General HospitalHaikou 570311Hainan ProvinceChina Operation Room The Second Affiliated Hospital of Hainan Medical CollegeHaikou 570311Hainan ProvinceChina Department of General Practice Hainan West Central HospitalDanzhou 571700Hainan ProvinceChina

BACKGROUND The nursing working environment is an important subsystem in the hospital environment.A good working environment could have a positive impact on ***,the work-family conflict and unsatisfactory working environment could significantly reduce their working enthusiasm,efficacy as well as the overall quality of the nursing,increase their fatigue,and thereby compromise their career *** To explore the possible status quo and to analyze the correlation between work environment perception and the work-family conflict among nurses in the operating *** A total of 312 operating room nurses from two first-class hospitals at Grade 2 and two first-class hospitals at Grade 3 in China from May to September 2017 were included in this research using the cluster sampling *** data,including the general information questionnaire,the practice environment scale of the nursing work index(PES-NWI),and the work-family conflict scale,were systematically *** correlation analysis was applied to analyze the correlation between the two scores,with influencing factors analyzed by hierarchical regression *** A total of 312 questionnaires were issued,and the response rate and effective questionnaire rate were both 96.15%(300/312).The total scores of the PES-NWI scale and the work-family conflict scale were 3.07±0.43(vs maximum up to 4 points)and 52.32±8.79(vs maximum up to 90 points),*** scores of the PES-NWI scale were negatively correlated with that of work-family conflict scale(all P<0.05).The perception of the nursing work environment and the number of night shifts per month were the major factors contributing to the workfamily conflict(all P<0.05).CONCLUSION The nursing work environment and the work-family conflict among nurses in the operating room were both found at a medium level with a negative correlation between the two.

关键词： Operating room nurses Perception of nursing work environment Workfamily conflict Correlation Influencing factors

Adding the impacts of biological crusts on sand and dust storm emission in Asia

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Advances in Climate Change Research 2023年第3期14卷 406-415页

作者： Jian ZHANG chun-Hong ZHOU Jian-Yan LU Hong WANG Xiao-ye ZHANG Key Laboratory for AerosoleCloudePrecipitation of China Meteorological Administration Nanjing University of Information Science&TechnologyNanjing 210044China State Key Laboratory of Severe Weather and Key Laboratory of Atmospheric Chemistry of Chinese Academy of Meteorological Sciences&Institute of Atmospheric Composition Beijing 100081China Center for Excellence in Regional Atmospheric Environment Institute of Urban EnvironmentChinese Academy of SciencesXiamen 361021China

Although biological crusts(biocrusts)grant stability to dust source areas by inhibiting dust emission,only a few models have explicitly considered their inhibitory *** this study,we used the China Meteorological Administration Unified Atmospheric Chemistry Environment/Dust model and combined retrieved biocrust information with two biocrust inhibition schemes(roughness length and biocrust strength schemes)to study numerically the inhibitory effect of biocrusts on a strong dust storm that occurred in Central and East Asia on 25−30 *** inhibitory effect of biocrusts on dust emission increased with biocrust *** total dust emission forecasted by the roughness length and biocrust strength schemes was reduced by approximately 56.7%and 47.9%on average,*** downstream sites in China,the surface mass concentrations of PM10 forecasted by the roughness length and biocrust strength schemes decreased by 36%–57%and 24%–41%,*** biocrusts were considered,the forecast for stations near the dust source area considerably improved and that for stations distant from the source area became more reasonable but with larger bias under the combined effects of emission,transport and deposition.

关键词： Biological crust Dust emission CUACE/Dust Roughness length scheme Biocrust strength scheme