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Rare Metals 2014年第2期33卷 144-148页

作者： Jing-Yang Chen La-mei cao Ming Xue Li-Jun Liu Science and Technology on Advanced High Temperature Structural Materials Laboratory Beijing Institute of Aeronautical Materials

The influence of heat treatment on the microstructure and stress-rupture property at 1,100 °C/140 MPa was investigated in a 5.0 wt% Re containing experimental single crystal Ni-base superalloy. The results indicate that the γmorphology is nearly cuboidal in the dendrite core after conventional heat treatment. The lattice misfit of alloy becomes more negative after modified heat treatment and results in more cuboidal γ precipitates than that after conventional heat treatment. The increased stress-rupture life after modified heat treatment is attributed to higher γ volume fraction, more negative lattice misfit, well-rafted structure, and narrower c channel width.

关键词： Superalloy Heat treatment γprecipitate Lattice misfit Stress-rupture property

Treadmill training improves neurological deficits and suppresses neuronal apoptosis in cerebral ischemic stroke rats

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Neural Regeneration Research 2019年第8期14卷 1387-1393页

作者： Li-mei cao Zhi-Qiang Dong Qiang Li Xu Chen Department of Neurology Shanghai No.8 People’s Hospital

RehabilNation training is believed to be beneficial to patients with stroke, but its molecular mechanism is still unclear. Rat models of cerebral ischemic stroke were established by middle cerebral artery occlusion/reperfusion, and then received treadmill training of different intens让ies, twice a day for 30 minutes for 1 week. Low-intensity training was conducted at 5 m/min, with a 10-minute running, 10-minute rest, and 10-minute running cycle. In the moderate-intensity training, the intensity gradually increased from 5 m/min to 10 m/min in 5 minutes, with the same rest cycle as above. In high-intensity training, the intensity gradually increased from 5 m/min to 25 m/min in 5 minutes, with the same rest cycle as above. The Bederson scale was used to evaluate the improvement of motor function. Infarct volume was detected using 2,3,5-triphenyltetrazolium chloride staining. Terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling staining was applied to detect the apoptosis of nerve cells in brain tissue. Western blot assay was employed to analyze the activation of cyclic adenosine monophosphate (cAMP)/protein kinase A and Akt/glycogen synthase kinase-3卩 signaling pathways in rat brain tissue. All training intensities reduced the neurological deficit score, infarct volume, and apoptosis in nerve cells in brain tissue of stroke rats. Training intensities activated the cAMP/protein kinase A and Akt/glycogen synthase kinase-3 beta signaling pathways. This activation was more obvious with higher training intensities. These changes were reversed by intracerebroventricular injection of protein kinase A inhibitor Rp-cAMP. Our findings indicate that the neuroprotective effect of rehabilitation training is achieved via activation of the cAMP/ protein kinase A and Akt/glycogen synthase kinase-3 beta signaling pathways. This study was approved by the Ethics Committee of Animal Experimentation in Shanghai No. 8 Peoples Hospital, China.

关键词： nerve regeneration ischemic stroke treadmill training neuronal deficit apoptosis cyclic adenosine monophosphate protein kinase A glycogen synthase kinase-3^ neuroprotective effect neural regeneration

Visible-light-mediated external-reductant-free reductive cross coupling of benzylammonium salts with(hetero)aryl nitriles

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Science China Chemistry 2019年第11期62卷 1519-1524页

作者： Meng Miao Li-Li Liao Guang-mei cao Wen-Jun Zhou Da-Gang Yu Key Laboratory of Green Chemistry&Technology of Ministry of Education College of ChemistrySichuan UniversityChengdu 610064China College of Chemistry and Chemical Engineering Neijiang Normal UniversityNeijiang 641100China

Herein we report a novel visible-light-mediated external reductant-free reductive cross coupling for the construction of C sp2–C sp3 bonds.A variety of benzylammonium salts underwent selective coupling with(hetero)aryl nitriles to deliver important diarylmethanes under mild reaction ***,photocatalysts can be omitted for many cases,which might involve the electron donor acceptor(EDA)*** studies indicated benzylic radicals might be involved as the key ***,the in situ generated NMe3 via cleavage of C–N bond in ammonium salts acts as the electron donor,thus avoiding the use of external-reductant.

关键词： reductive cross coupling visible light external-reductant-free

Interaction of Photoactive[Fe(CN)_6]^(4-) with TiO_2 Anatase(101) Surface:A Periodic Density Functional Theory Study

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Chinese Journal of Structural Chemistry 2007年第3期26卷 361-366页

作者： XU Ying CHEN Wen-Kai cao mei-Juan LIU Shu-Hong LI Jun-Qian Department of Chemistry Fuzhou University Fuzhou Fujian 350002 China

The plane-wave pseudopotential function method, based on density-functional theory, has been used to calculate the adsorption, electronic band structures, orbitals and optical absorption spectrum of [Fe（CN）6]^4- on TiOz anatase（101） surface. Our calculations reveal that the surface-modified anatase system has large adsorption energy and a much narrower band gap. [Fe（CN）6]^4- adsorption on the （101） surface could lead to a large red shift of the anatase optical absorption threshold, which extends into a visible region significantly. The calculated results are in agreement with the experiment and other theoretical studies reasonably. It is very important for the understanding and further development ofphotovoltaic materials that are active under visible light.

关键词： density functional theory (DFT) [Fe(CN)6]^4- anatase(101) surface adsorption absorption

Linearity optimization of edge filter demodulators in FBG_s

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Optoelectronics Letters 2008年第3期4卷 193-195页

作者： LI Dong-sheng SUI Qing-mei cao Yu-qiang Optical Fiber Sensor Technology and Engineering Research Center Shandong University Jinan 250061 China

A kind of electric circuit is improved to optimize the linearity of edge filter demodulators in FBG .By using a logarithm amplifier and an extraction operation, the linear range of optimized edge filter demodulators has been broadened effectively, and the requirement of optical filter＇s linear range has been reduced. Theoretical analyses and the simulation results indi-cated that the linear range of optimized edge fdter demodulator＇s covers the whole transition region of the edge filter, while a strict linearity of the optical filter is not necessary.

关键词：光纤解调器线性分析分析方法

Two New Antibacterial Flavanones from Sophora flavescens

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Chinese Chemical Letters 2006年第8期17卷 1048-1050页

作者： mei Ai cao Xiao Bai SUN Pei Hua ZHAO Cheng Shan YUAN State Key Laboratory of Applied Organic Chemistry College of Chemistry and Chemical Engineering Lanzhou University Lanzhou 730000

Two new lavandulylated flavanones,（2R, 3R）-8-1avandulyl-2＇-methoxy-5, 7, 4＇-trihydroxyflavanonol （1） and 8-1avandulyl-5,7, 4＇-trihydroxyflavonol （2）,were isolated from the dry roots of S *** structures were e... 详细信息

关键词： Sophora flavescens Fabaceae flavanone antibacterial activity.

Joining of C_f/SiBCN composite with CuPd-V filler alloy

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Journal of Materials Science & Technology 2018年第9期34卷 1652-1659页

作者： Wen-Wen Li Bo Chen La-mei cao Wei Liu Hua-Ping Xiong Yao-Yong Cheng Welding and Plastic Forming Division Beijing Institute of Aeronautical Materials Beijing 100095 China Science and Technology on Advanced High Temperature Structural Materials taboratory Beijing Institute of Aeronautical Materials Beijing 100095 China

Two compositions of CuPd-V system filler alloy were designed for joining the Cf/SiBCN composite. Their dynamic wettability on the Cf/SiBCN composite was studied with the sessile drop method. The CuPd-8 V alloy exhibited a contact angle of 57° after holding at 1170℃ for 30 min, whereas for CuPd-13 V alloy,a lower contact angle of 28°can be achieved after heating at 1200 ℃ for 20 min. Sound Cf/SiBCN joints were successfully produced using the latter filler alloy under the brazing condition of（1170-1230）℃for 10 min. The results showed that the active element V strongly diffused to the surface of Cf/SiBCN composite, with the formation of V2 C/VN reaction layer. The microstructure in the central part of the joint brazed at 1200 ℃ was characterized by the V2 C/VN particles distributing scatteringly in CuPd matrix. The corresponding joints showed the maximum three-point bend strength of 82.4 MPa at room *** the testing temperature was increased to 600 0 C, the joint strength was even elevated to 108.8 ***, the joints exhibited the strength of 92.4 MPa and 39.8 MPa at 800 ℃ and 900 ℃, respectively.

关键词： Cf/SiBCN composite Wettability Joint strength Interfacial reaction

Chaihu-Shugan-San exerts an antidepressive effect by downregulating miR-124 and releasing inhibition of the MAPK14 and Gria3 signaling pathways

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Neural Regeneration Research 2018年第5期13卷 837-845页

作者： Qiong Liu Ning-Ning Sun Zheng-Zhi Wu Da-Hua Fan mei-Qun cao Department of Cardiovascular Medicine Xiang Ya Hospital of Central South University Changsha Hunan Province China Shenzhen Institute of Geriatrics Shenzhen Second People's Hospital The First Affiliated Hospital of Shenzhen University Shenzhen Guangdong Province China The Eighth Affiliated Hospital of Sun Yat-sen University Shenzhen Guangdong Province China Chinese and Wsetern Integrative Medicine Shcool of Medicine Jinan University Guangzhou Guangdong Province China.

Dysregulation of mi R-124 has been reported to be involved in the pathophysiology of depression. Chaihu-Shugan-San, a traditional Chinese medicine, has antidepressive activity; however, the underlying mechanisms remain unclear. In this study, to generate a rodent model of depression, rats were subjected to a combination of solitary confinement and chronic unpredictable mild stress for 28 days. Rats were intragastrically administered Chaihu-Shugan-San（2.835 m L/kg/d） for 4 weeks, once a day. Real-time reverse-transcription quantitative polymerase chain reaction, mi RNA microarray, western blot assay and transmission electron microscopy demonstrated that ChaihuShugan-San downregulated mi R-124 expression and upregulated the m RNA and protein levels of mitogen-activated protein kinase 14（MAPK14） and glutamate receptor subunit 3（Gria3）. Chaihu-Shugan-San also promoted synapse formation in the hippocampus. The open field test, sucrose consumption test and forced swimming test were used to assess depression-like behavior. After intragastric administration of Chaihu-Shugan-San, sucrose consumption increased, while the depressive behaviors were substantially reduced. Together, these findings suggest that Chaihu-Shugan-San exerts an antidepressant-like effect by downregulating mi R-124 expression and by releasing the inhibition of the MAPK14 and Gria3 signaling pathways.

关键词： nerve regeneration traditional Chinese medicine Chaihu-Shugan-San depression open-field test sucrose consumption test forced swimming test miR-124 neural plasticity MAPK14 Gria3 neural regeneration

Fabrication of solid-phase-sintered Si C-based composites with short carbon fibers

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International Journal of Minerals,Metallurgy and Materials 2014年第11期21卷 1141-1145页

作者： Xian-hui Li Qing-zhi Yan Yong-jun Han mei-qi cao Chang-chun Ge Institute of Special Ceramics and Powder Metallurgy University of Science and Technology Beijing

Solid-phase-sintered Si C-based composites with short carbon fibers（Csf/SSi C） in concentrations ranging from 0 to 10wt% were prepared by pressureless sintering at 2100°C. The phase composition, microstructure, density, and flexural strength of the composites with different Csf contents were investigated. SEM micrographs showed that the Csf distributed in the SSi C matrix homogeneously with some gaps at the fiber/matrix interfaces. The densities of the composites decreased with increasing Csf content. However, the bending strength first increased and then decreased with increasing Csf content, reaching a maximum value of 390 MPa at a Csf content of 5wt%, which was 60 MPa higher than that of SSi C because of the pull-out strengthening mechanism. Notably, Csf was graphitized and damaged during the sintering process because of the high temperature and reaction with boron derived from the sintering additive B4C; this graphitization degraded the fiber strengthening effect.

关键词： fiber-reinforced composites silicon carbide carbon fibers solid phase sintering microstructure

Familial nasopharyngeal carcinomas possess distinguished clinical characteristics in southern China

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Chinese Journal of Cancer Research 2014年第5期26卷 543-549页

作者： Su-mei cao Sui-Hong Chen Chao-Nan Qian Qing Liu Yun-Fei Xia State Key Laboratory of Oncology in South China and Department of Cancer Prevention Research Sun Yat-Sen University Cancer Center State Key Laboratory of Oncology in South China and Department of Nasopharyngeal Carcinoma Sun Yat-Sen University Cancer Center State Key Laboratory of Oncology in South China and Department of Radiation Oncology Sun Yat-Sen University Cancer Center

Objective： To compare clinical characteristics between familial nasopharyngeal carcinomas（NPCs） and sporadic NPCs in Guangdong province, China, a high-risk area.Methods： Between 1991 and 2001, 993 NPC patients treated at the Cancer Center of Sun Yat-Sen University in Guangdong were randomly selected as probands. Information about NPC among the probands＇ relatives and other information were obtained from a retrospective review of the patients＇ medical records. The patients were divided into sporadic NPC, low-frequency familial NPC（one NPC patient in addition to the proband in three generations）, and high-frequency familial NPC（2 or more additional NPC patients in three generations） groups. Pathological and clinical characteristics were compared among these groups.Results： Of the 993 patients, 131（13.2%） had a familial history of NPC. The average age at diagnosis was the lowest in the high-frequency familial NPC group（39 years; P=0.048）. Although the overall survival（OS）, distant metastasis-free survival（DMFS）, and disease-free survival（DFS） rates did not differ between familial and sporadic NPCs, the locoregional recurrence-free survival（LRFS） rate increased in the order sporadic NPCs, low-frequency familial NPCs, and high-frequency familial NPCs（P=0.009）, with 5-year rates of 70%, 83%, and 87%, respectively. Multivariate analysis showed that family history of NPC was an independent favorable prognostic factor for LRFS, with adjusted hazard ratio（a HR） of 0.548, 95% CI（0.342-0.878）. The high LRFS for familial NPCs was mainly noted among young, advanced-stage patients who received continuous radiation treatment.Conclusions： Genetic factors may play an important role in the etiology of high-frequency familial NPC and underlie the early age of onset and sensitivity to radiotherapy.

关键词： Nasopharyngeal carcinoma(NPC) familial clinical behavior