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Chinese Physics B 2015年第10期24卷 496-500页

作者：朱哲陈玉博郑学军 School of Materials Science and Engineering Xiangtan University School of Mechanical Engineering Xiangtan University

The switching process of ferroelectric thin films in electronic devices is one of the most important requirements for their application. Especially for the different external fields acting on the film surface, the mechanism of domain switching is more complicated. Here we observe the nanoscale domain switchings of Bi3.15Eu0.85Ti3O12 thin film under different mechanical forces at a fast scan rate. As the force increases from initial state to 247.5 n N, the original bright or grey contrasts within the selected grains are all changed into dark contrasts corresponding to the polarization vectors reversed from the up state to the down state, except for the clusters. As the mechanical force increases to 495 n N, the color contrasts in all of the selected grains further turn into grey contrasts and some are even changed into grey contrasts completely showing the typical 90° domain switching. When another stronger loading force 742.5 n N is applied, the phase image becomes unclear and it indicates that the piezoelectric signal can be suppressed under a sufficiently high force, which is coincident with previous experimental results. Furthermore, we adopt the domain switching criterion from the perspective of equilibrium state free energy of ferroelectric nanodomain to explain the mechanisms of force-generated domain switchings.

关键词： thin film domain switching mechanical force piezoresponse force microscopy

Kinetics and FTIR characteristics of the pyrolysis process of poplar wood

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Forestry Studies in China 2013年第1期15卷 70-75页

作者： Wen-Liang WANG xue-Yong REN Yan-zhe CHE Jian-Min CHANG Jin-Sheng GOU College of Materials Science and Technology Beijing Forestry University

The pyrolysis characteristics of residues of poplar （Populus sp.） wood were investigated using a thermogravimetric analyzer coupled with a Fourier transform infrared （TG-FTIR） spectrometer. The pyrolysis process was sub- divided into four stages at a rate of 10℃.min-1, varying from 30 to 650℃. Below 180℃, a mass loss occurred for drying and preheating the sample and the onset temperature of pyrolysis ranged between 180-260℃. A significant mass loss 3f 61.4 wt.% occurred between 260-380℃, followed by a slow and continuous mass change with lignin devolatilization. The analysis of kinetic reactions showed that the activation energy （78.29 ***-1） in the low-temperature section was much larger than that （6.40 kJ-mol-1） in the high-temperature section. The evolved gases formed by thermal degradation 3f poplar wood were simultaneously analyzed by FTIR. It was observed from the main peaks that the emissions evolved during poplar wood pyrolysis were acetic acid, carbon dioxide, carbon monoxide, methane, water, some volatile com- 3ounds of esters, alcohols and aldehydes. The emissions gradually increased with rising temperatures before a strong 3eak around 360℃ and then decreased. Most gaseous products were emitted in the 320-380℃ range, while CO2 was =ontinuously emitted in a wide range from 140-550℃.

关键词： poplar wood pyrolysis TG-FTIR kinetics characteristics

Leaching kinetics of selenium from copper anode slimes by nitric acid-sulfuric acid mixture

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Transactions of Nonferrous Metals Society of China 2018年第1期28卷 186-192页

作者： Hong-ying YANG xue-jiao LI Lin-lin TONG zhe-nan JIN Lu yin Guo-bao CHEN School of Metallurgy Northeastern University Shenyang 110819 China

The leaching kinetics of selenium from copper anode slimes was studied in a nitric acid?sulfuric acid *** effects of main parameters on selenium leaching showed that the leaching rate of selenium was practically independent of stirring speed,while dependent on temperature and the concentrations of HNO3and *** leaching of selenium includes two *** activation energy in the first stage is103.5kJ/mol,and the chemical reaction is the rate controlling *** was almost independent of H2SO4concentration and dependent on HNO3concentration since the empirical reaction order with respect to HNO3concentration *** the second stage,the activation energy is30.6kJ/mol,and the process is controlled by a mixture of diffusion and chemical *** leaching of selenium was almost independent of HNO3concentration.

关键词： selenium kinetics acid leaching copper anode slimes

Wildfire associated with a deciduous broadleaved forest from the Neogene Baoshan Basin at the southeastern margin of the Tibetan Plateau

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Journal of Palaeogeography 2023年第3期12卷 448-462页

作者： Yong-Jiang Huang Arata Momohara Shu-Feng Li xue-ping Ji Jian Qiu Lin-Bo Jia Jin-Jin Hu Yun-Heng Ji zhe-Kun Zhou Key Laboratory for Plant Diversity and Biogeography of East Asia Kunming Institute of BotanyChinese Academy of SciencesKunming 650201Yunnan ProvinceChina Graduate School of Horticulture Chiba UniversityChiba 271-8510Japan Key Laboratory of Tropical Forest Ecology Xishuangbanna Tropical Botanical GardenChinese Academy of SciencesMengla 666303Yunnan ProvinceChina Kunming Natural History Museum of Zoology Kunming Institute of ZoologyChinese Academy of SciencesKunming 650223Yunnan ProvinceChina School of Material and Chemical Engineering Southwest Forestry UniversityKunming 650224Yunnan ProvinceChina

Wildfire bears a close relationship with vegetation as its fuel *** southeastern margin of the Tibetan Plateau witnesses frequent wildfires among various types of vegetation,whereas such wide in-teractions between wildfire and vegetation remain poorly studied from geological *** this study,we reported a local fire using sedimentary macroscopic charcoals from the latest Miocene to early Pliocene of the Baoshan Basin in this region,and then inferred the local vegetation at the time of the fire event based chiefly on the coexistent fruit and seed fossil *** taxonomic results show that the charcoal assemblage is probably dominated by broadleaved plants and the fruit and seed fossil assemblage is apparently dominated by Salix(Salicaceae)followed by Sambucus(Adoxaceae),suggesting a deciduous broadleaved forest in which the fire likely *** a seasonally dry climate associated with the Asian monsoon,this type of vegetation might be prone to natural fire,because in the wet rainy season the plants grew well to accumulate biofuel and in the dry season abundant ground litter resulting from leaf decay would be desiccated to become highly *** to the fire-tolerant habit of Salix as the dominant plant,the forest might be in return adapted to the fire event or even more fires that potentially *** these may suggest a close relationship between the fire event and the reconstructed *** finding documents a new type of wildfire—vegetation interaction,namely the interaction between wildfire and deciduous broadleaved forest,from the geological past at the southeastern margin of the Tibetan *** therefore sheds new light on the wildfire history coupling vegetation change in the region.

关键词： Charcoal Fossil carpology Salix Sambucus Precipitation seasonality

Propofol inhibits neuronal differentiation of mouse embryonic stem cells in vitro

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Chinese Medical Journal 2013年第21期126卷 4186-4188页

作者： Wang Hao Luo zhe xue Zhang-gang Cang Jing Fudan Univ Shanghai Med Coll Zhongshan Hosp Dept Anesthesiol Shanghai 200032 Peoples R China

Propofol （2, 6-diisopropylphenol） is a general intravenous anesthetic which plays roles in the central neural system by binding GABAA receptors （GABAARs） and enhancing the chloride channels of the neurons.1 Previous studies mainly focused on the effects of anesthetics on mature neurons, but little attention was paid to their role in early neural differentiation or neural stem cells. Therefore, in the present study, we choose the widely used mouse embryonic cells （ES） cells as the model to investigate the potential effect ofpropofol on neuronal differentiation.

关键词： propofol neuronal differentiation mouse embryonic stem cells

Enhancing the Robustness of the Microcavity Coupling System

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Chinese Physics Letters 2011年第3期28卷 100-103页

作者： YAN ying-Zhan JI zhe YAN Shu-Bin LIU Jun xue Chen-Yang ZHANG Wen-Doug XIONG Ji-Jun Key Laboratory of Instrumentation Science and Dynamic Measurement North University of ChinaTaiyuan 030051 Science and Technology on Electronic Test and Measurement Laboratory North University of ChinaTaiyuan 030051

A novel method to enhance the robustness of the microcavity coupling system(MCS)is presented by encapsulating and solidifying the MCS with a low refractive index(RI)curable UV *** encapsulating process is illustrated in detail for a typical microsphere with a radius of R about 240μ*** differences of the resonant characteristics before and after the package are observed and *** first two differences refer to the enhancement of the coupling strength and the shift of the resonant spectrum to the longer wavelength,which are both mainly because of the microsphere surrounding RI *** difference is the quality factor(Q-factor)which decreases from 7.8×10^(7)to 8.7×10^(6)after the package due to the polymer ***,rotation testing experiments have been carried out to verify the robustness of the package *** results demonstrate that the packaged MCR has much better robust performance than the un-package *** enhancement of the robustness greatly promotes the microcavity research from fundamental investigations to application fields.

关键词： resonant coupling rotation

c-Myc promotes tubular cell apoptosis in ischemia-reperfusion-induced renal injury by negatively regulating c-FLIP and enhancing FasL/Fas-mediated apoptosis pathway

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Acta Pharmacologica Sinica 2019年第8期40卷 1058-1066页

作者： Dan Xu Bao Wang Pan-pan Chen Yan-zhe Wang Nai-jun Miao Fan yin Qian Cheng Zhuan-li Zhou Hong-yan Xie Li Zhou Jun Liu Xiao-xia Wang Hong xue Wei Zhang Li-min Lu Department of Physiology and Pathophysiology School of Basic Medical SciencesShanghai Medical CollegeFudan University Department of Nephrology Shanghai Tong Ren HospitalShanghai Jiao Tong University School of Medicine

c-Myc plays an important role in cell proliferation,differentiation,and cell ***/Fas pathway is a key regulator of cell *** study was aimed to investigate the effects of c-Myc on the FasL/Fas pathway in ischemia-reperfusion(I/R)-induced renal *** were objected to bilateral renal ischemia for 60 min and reperfused for 24 or 48 ***-52 E cells were treated with hypoxia-reoxygenation(H/R)or *** was used to identify the distribution of *** apoptosis was assessed by TUNEL ***-c-Myc and recombinant pcDAN 3.0 were used to overexpress c-Myc and c-FLIP,*** assay and luciferase assay were used to detect the binding of c-Myc to c-FLIP *** I/R rats,c-Myc was increased significantly and mainly located in renal tubular epithelial cells;meanwhile,c-FLIP was decreased,cleaved caspase-8,cleaved caspase-3 and TUNEL-positive staining cells were *** of I/R rats with c-Myc inhibitor 10058-F4 significantly attenuated the decrease in c-FLIP,the increase in cleaved caspase-8,cleaved caspase-3,TUNEL-positive cells,Scr and BUN in I/R *** NRK-52 E cells,hypoxia and reoxygen induced the increase in c-Myc and decrease in *** and luciferase assay results indicated that cMyc binds to the promoter region of c-FLIP *** of c-Myc markedly decreased *** of c-FLIP inhibited the increase in cleaved caspase-8 and caspase-3 induced by *** indicated that c-Myc is increased in kidneys of I/R rats and negatively regulates the expression of c-FLIP,then enhanced FasL-induced cell apoptosis in I/R stress.

关键词： c-Myc c-FLIP Fas/Fas ischemia-reperfusion tubular cell apoptosis

Charge density wave order and electron-boson coupling in ternary superconductor Bi_(2)Rh_(3)Se_(2)

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Science China(Physics,Mechanics & Astronomy) 2023年第7期66卷 120-126页

作者： Zi-Teng Liu Chen Zhang Qi-Yi Wu Hao Liu Bo Chen Zhi-Bo yin Sheng-Tao Cui zhe Sun Shuang-Xing Zhu Jiao-Jiao Song yin-Zou Zhao Hong-Yi Zhang xue-Qing Ye Fan-ying Wu Shu-Yu Liu Xiao-Fang Tang Ya-Hua Yuan Yun-Peng Wang Jun He Hai-Yun Liu Yu-Xia Duan Jian-Qiao Meng School of Physics and Electronics Central South UniversityChangsha 410083China National Synchrotron Radiation Laboratory University of Science and Technology of ChinaHefei 230029China Department of Physics and Electronic Science Hunan University of Science and TechnologyXiangtan 411201China Beijing Academy of Quantum Information Sciences Beijing 100085China

The newly discovered ternary chalcogenide superconductor Bi_(2)Rh_(3)Se_(2) has attracted growing attention,which provides an opportunity to explore the interplay between charge density wave(CDW)order and ***,whether the phase transition around 240 K can be attributed to the formation of CDW remains *** help resolve the debate,we study the electronic structure of Bi_(2)Rh_(3)Se_(2) by angle-resolved photoemission spectroscopy,focusing on the nature of its high-temperature phase transition around 240 *** measurements demonstrate that the phase transition at 240 K is a second-order CDW phase *** results reveal(i)a 2×2 CDW order in Bi_(2)Rh_(3)Se_(2),accompanied by the reconstruction of electronic structure,such as band folding,band splitting,and opening of CDW gaps at and away from the Fermi level;(ii)the existence of electron-boson coupling,which is manifested as an apparent kink and peak-dip-hump structure in *** observations thus enable us to shed light on the nature of CDW order and superconductivity in Bi_(2)Rh_(3)Se_(2).

关键词： charge density wave electron-boson coupling angle-resolved photoemission spectroscopy electronic structure Chalcogenide

Panaxadiol inhibits programmed cell deathligand 1 expression and tumor proliferation via hypoxia-inducible factor(HIF)-1a and STAT3 in human colon cancer cells

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中国药理学与毒理学杂志 2019年第10期 888-889页

作者： WANG zhe LI Ming-yue ZHANG Zhi-hong MA Juan JIN xue-jun Molecular Medicine Research Center Colege of PharmacyYanbian University

OBJECTIVE To investigate the potential anti-cancer activity of panaxadiol on PD-L1 expression and tumor proliferation in human colon cancer cells and to identify the underlying mechanism. METHODS HCT116, SW620, and HT29 cells were pretreated with panaxadiol(1, 3, 10, 30 μmol·L-1) for 48 h to verify cell viability by MTT assay. HCT-116 cells were pretreated with panaxadiol(1, 3, 10 μmol·L-1) for 12 h in Western blotting, flow cytometry analysis, and reverse transcription-PCR（RTPCR）. The interaction between panaxadiol and HIF-1α/STAT3 was studied by molecular docking and immunofluorescence. HCT-116/T-cell coculture model and T-cell killing assay were employed to investigated the immunosuppressive of HCT-116 cells. Colony cormation and Ed U labeling assay were performed to detect cell proliferation. Panaxadiol at a dose of 10 and 30 mg·kg-1were orally administered in xenografted assay and Immunohistochemical analysis. RESULTS Panaxadiol showed little cytotoxicity according to the result of MTT assay and exerted a potent inhibitory activity against PD-L1 expression both on cell surface and protein/m RNA level in a dose-dependent manner. It was subsequently shown that panaxadiol inhibited STAT3 activation through JAK1,JAK2, and Src pathways. Simultaneously panaxadiol promoted degradation and depressed synthesis of HIF-αprotein induced by hypoxia. Moreover, pretrement of panaxadiol could restore the activity of cytotoxic T lymphocyte（CTL） and regain their capacity of tumor cell killing in a T cell/tumor cell co-culture system. Colony formation and Ed U labeling assays Further demonstrated that panaxadiol inhibited tumor proliferation. The Proliferation inhibitory effect in vivo of panaxadiol was also proved by xenograft assay. CONCLUSION Taken together, these studies reveal previously unknown characteristics of panaxadiol provide new perspectives into the mechanism of cancer inhibition of the compound.

关键词： panaxadiol PD-L1 HIF-1α STAT3 proliferation

Synergistic anti-liver cancer effects of curcumin and total ginsenosides

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World Journal of Gastrointestinal Oncology 2020年第10期12卷 1091-1103页

作者： zhe Deng Xiao-Yan Xu Fenny Yunita Qing Zhou Yong-Rong Wu Yu-Xing Hu Zhi-Qi Wang xue-Fei Tian Department of Internal Medicine College of Integrated Chinese and Western MedicineHunan University of Chinese MedicineChangsha 410208Hunan ProvinceChina Hunan Key Laboratory of Translational Research in Formulas and zheng of Traditional Chinese Medicine Hunan University of Chinese MedicineChangsha 410208Hunan ProvinceChina The First Affiliated Hospital Hunan University of Chinese MedicineChangsha 410208Hunan ProvinceChina School of Basic Chinese Medical Sciences Hunan University of Chinese MedicineChangsha 410208Hunan ProvinceChina College of Pharmaceutical Sciences Hunan University of Chinese MedicineChangsha 410208Hunan ProvinceChina

BACKGROUND Liver cancer is the sixth most frequently occurring cancer in the world and the fourth most common cause of cancer *** pathogenesis of liver cancer is closely associated with inflammation and immune response in the tumor *** therapeutic agents for liver cancer,which can control inflammation and restore cellular immunity,are ***(Cur)is a natural anti-inflammatory drug,and total ginsenosides(TG)are a commonly used immunoregulatory *** note,both Cur and TG have been shown to exert anti-liver cancer *** To determine the synergistic immunomodulatory and anti-inflammatory effects of Cur combined with TG in a mouse model of subcutaneous liver *** A subcutaneous liver cancer model was established in BALB/c mice by a subcutaneous injection of hepatoma cell *** were treated with Cur(200 mg/kg per day),TG(104 mg/kg per day or 520 mg/kg per day),the combination of Cur(200 mg/kg per day)and TG(104 mg/kg per day or 520 mg/kg per day),or 5-fluorouracil combined with cisplatin as a positive control for 21 *** volume was measured and the protein expression of programmed cell death 1 and programmed cell death 1 ligand 1(PD-L1),inflammatory indicators Toll like receptor 4(TLR4)and nuclear factor-κB(NF-κB),and vascular growth-related factors nitric oxide synthases(iNOS)and matrix metalloproteinase 9 were analyzed by Western blot ***4+CD25+Foxp3+regulatory T cells(Tregs)were counted by flow *** The combination therapy of Cur and TG significantly inhibited the growth of liver cancer,as compared to vehicle-treated animals,and TG showed dose *** combined with TG-520 markedly decreased the protein expression of PD-L1(P<0.0001),while CD4+CD25+Foxp3+Tregs regulated by the PD-L1 signaling pathway exhibited a positive correlation with *** combined with TG-520 also inhibited the cascade action mediated by NF-κB(P<0.0001),thus inhibiting the TLR4/NF-κB signalling pathway(

关键词： Total ginsenosides Curcumin Liver cancer Immune Inflammation Programmed cell death 1 ligand 1