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growth and Characterization of Perovskite K1-yLiyTa1-xNbxO3∶Ce

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Journal of Rare Earths 2006年第Z1期24卷 261-263页

作者： Tian Hao He Chongjun Shen Yanqing Xin Jiangbo Zhou Zhongxiang Department of Physics Harbin Institute of Technology Harbin 150001 China Department of Physics Harbin Institute of Technology Harbin 150001 China Department of Physics Harbin Institute of Technology Harbin 150001 China Department of Physics Harbin Institute of Technology Harbin 150001 China Department of Physics Harbin Institute of Technology Harbin 150001 China

The grown Ce doped potassium lithium tantalite niobate (KLTN) crystals and characterize their physical properties were reported. The top seeded solution growth method was described. The specifics of a particular KLTN∶Ce growth were presented. X-ray diffraction spectra of paraelectric and ferroelectric KLTN crystals were illustrated. Dielectric and absorption studies on KLTN∶Ce were carried out compared with pure KLTN.

关键词： top seeded solution growth KLTN X-ray diffraction dielectric materials

growth and passivation of aluminum etch tunnels at on-off controlling direct current in 6 wt.% HCI solution

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Rare Metals 2008年第2期27卷 205-209页

作者： WANG Mei HE Yedong Beijing Key Laboratory for Corrosion Erosion and Surface Technique University of Science and Technology Beijing Beijing 100083 China

growth and passivation of tunnels within Al foil by on-off controlling DC etching in 6 wt.% HCI solution has been investigated. It was found that, in a given etchant solution at a special temperature, the longest tunnel length was only a function of the turn-on interval of DC. The potential of Al foil broke at on-off controlling DC by the result from anode polarization curves and potential-time （E-t） responding curves. When DC was switched on, the potential increased abruptly over pitting potential, leading to nucleation of pits at the surface and the growth of tunnels at special length. When DC was switched off, the potential decreased rapidly to a passive value, leading to stoppage of nucleation and death of tunnels. By this way, the longest tunnel length can be controlled and a non-piercing layer can be obtained. Hence, etching of Al foil at this current is beneficial for maintaining a good mechanical strength.

关键词： aluminum electrolytic capacitor tunnel length growth passivation on-off controlling current

growth of ZnO Single Crystal by Chemical Vapor Transport Method

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Journal of Rare Earths 2006年第Z1期24卷 4-7页

作者： Zhao Youwen Dong Zhiyuan Wei Xuecheng Duan Manlong Li Jinmin Institute of Semiconductor Chinese Academy of Sciences Beijing 100083 China Institute of Semiconductor Chinese Academy of Sciences Beijing 100083 China Institute of Semiconductor Chinese Academy of Sciences Beijing 100083 China Institute of Semiconductor Chinese Academy of Sciences Beijing 100083 China Institute of Semiconductor Chinese Academy of Sciences Beijing 100083 China

ZnO crystals were grown by CVT method in closed quartz tube under seeded condition. Carbon was used as a transport agent to enhance the chemical transport of ZnO in the growth process. ZnO single crystals were grown by using GaN/sapphire and GaN/Si wafer as seeds. The property and crystal quality of the ZnO single crystals was studied by photoluminescence spectroscopy and X-ray diffraction technique.

关键词： zinc oxide chemical vapor transport single crystal growth

growth mechanism of reinforcements in in-situ synthesized (TiB+TiC)/Ti composites

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中国有色金属学会会刊：英文版 2001年第1期11卷 67-71页

作者：吕维洁张荻张小农郭淑玲吴人洁 Shanghai Jiaotong Univ. Shanghai 200030 China

The growth mechanism of reinforcement in in situ synthesized (TiB+TiC)/Ti composites was investigated. The results show that reinforcements nucleate and grow in a way of dissolution precipitation. The morphologies of reinforcements are closely related to the solidification paths and crystal structure of reinforcements. TiB, as a reinforcement, is liable to grow along [010] direction and forms in short fibre shape due to its B27 structure, whereas primary TiC is liable to form composition undercooling and grow in dendritic shape. TiC phases precipitated in binary eutectic and ternary eutectic reactions grow in equiaxial shape. The addition of aluminum element refines TiB and TiC particles, and makes TiC reinforcements grow into the equiaxial particles easily. The addition of graphite adjusts the solidification paths and forms more TiC with dendritic shape. [

关键词： TMCs in-situ reaction growth mechanism solidification path crystal structure

growth responses of Picea mongolica seedlings to defoliation rate

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Journal of Environmental Sciences 2005年第2期17卷 232-236页

作者： ZOUChun-jing HANShi-jie QIShu-yan XUWen-duo LIDao-tang CollegeofLifeScience＆Biotechnology ShanghaiJiaotongUniversityShanghai200030China／／InstituteofAppliedEcologyChineseAcademyofSciencesShenyang110016China InstituteofAppliedEcology ChineseAcademyofSciencesShenyang110016China NormalCollege ShenyangUniversityShenyang110016China CollegeofLifeScience＆Biotechnology ShanghaiJiaotongUniversityShanghai200030China

Picea mongolica W. D. Xu. is an endemic species in China. The spruce forest is only found in semi-arid habitat in Inner Mongolia Autonomous Region of China. Based on the simulative defoliation experiment, it was proved that Picea mongolica seedlings had the compensatory and overcompensatory effects under the certain defoliation rate. The results of variance analysis on growth indexes showed that in PM Ⅰ(natural regeneration seedlings under Picea mongolica forest), the differences of H 1(height in June 23) and H 2(height in September 3) were extremely significant, and the difference of D(diameter at the breast height) were not significant. In PM Ⅱ(artificial regeneration seedlings under Betula platyphylla Suk. forest), the difference of H 1 was significant, the difference of H 2 was not significant, and the difference of D was extremely significant. The regression equations were established and the compensatory and overcompensatory points were obtained. In PM Ⅰ, the compensatory points of H 1, H 2, and D were 0.7628, 0.7436, 0.5725, and the overcompensatory points were 0.6056, 0.5802 and 0.2909 respectively. In PM Ⅱ, the compensatory points of H 1, H 2, and D are 0.5012, 0.3421, 0.2488, and the overcompensatory points are 0.4137, 0.2633 and 0.0747 respectively. These results suggested that the induction of compensatory growth mechanisms in spruce seedlings required a threshold level of defoliation, and the insects in Picea mongolica forest could be controlled in a certain degree.

关键词： Picea mongolica W. D. Xu. compensate overcompensate growth defoliation rate

growth Inhibition Occurs Independently of Cell Mortality in Tomato (Solanum lycopersicum) Exposed to High Cadmium Concentrations

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Journal of Integrative Plant Biology 2008年第3期50卷 300-310页

作者： Christine Delpre Stanley Lutts Unitde Biologie vgtale Universitcatholique de Louvain5(Bte 13) Place Croix du Sud1348 Louvain-la-NeuveBelgium Unitde Biologie vgtale Universit catholique de Louvain5(Bte 13) Place Croix du Sud1348 Louvain-la-NeuveBelgium

In order to analyze the adaptation potential of tomato shoots to a sudden increase in Cd concentration, tomato plants （Solanum lycopersicum L. var. Ailsa Craig） were exposed under controlled environmental conditions to a high dose of this heavy metal （250 μm CdCl2） in nutrient solution for 7 and 14d. Both root and shoot growth was completely inhibited but all plants remained alive until the end of the treatment. Cell viability remained unaffected but the activity of the mitochondrial alternative pathway was stimulated by Cd stress at the expense of the cytochrome pathway. Cadmium concentration was higher in roots than in shoots and a decrease in the rate of net Cd translocation was noticed during the second week of stress. Cadmium decreased both leaf conductance （gl） and chlorophyll concentration. However, the effect on net CO2 assimilation remained limited and soluble sugars accumulated in leaves. Photochemical efficiency of PSII （FvlFm） was not affected despite a decrease in the number of reaction centers and an inhibition of electron transfer to acceptors of PSII. It is concluded that tomato shoot may sustain short term exposure to high doses of cadmium despite growth inhibition. This property implies several physiological strategies linked to both avoidance and tolerance mechanisms.

关键词： cadmium chlorophyll fluorescence growth heavy metal toxicity Lycopersicon esculentum tomato

growth differentiation factor-15 combined with N-terminal prohormone of brain natriuretic peptide increase 1-year prognosis prediction value for patients with acute heart failure: a prospective cohort study

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Chinese Medical Journal 2019年第19期132卷 2278-2285页

作者： Ji Hao Iokfai Cheang Li Zhang Kai Wang Hui-Min Wang Qian-Yun Wu Yan-Li Zhou Fang Zhou Dong-Jie Xu Hai-Feng Zhang Wen-Ming Yao Xin-Li Li Department of Cardiology The First Affiliated Hospital of Nanjing Medical UniversityNanjingJiangsu 210029China Department of Cardiology The Second Affiliated Hospital of Xuzhou Medical CollegeXuzhouJiangsu 221002China

Background:Clinical assessment and treatment guidance for heart failure depends on a variety of *** objective of this study was to investigate the prognostic predictive value of growth differentiation factor-15(GDF-15)and N-terminal prohormone of brain natriuretic peptide(NT-proBNP)in assessing hospitalized patients with acute heart failure(AHF).Methods:In total,260 patients who were admitted for AHF in the First Affiliated Hospital of Nanjing Medical University were enrolled from April 2012 to May *** history and blood samples were collected within 24 h after the *** primary endpoint was the all-cause mortality within 1 *** patients were divided into survival group and death group based on the *** established mortality risk factors and serum GDF-15 level,receiver-operator characteristic(ROC)analyses were *** regression analyses were used to further analyze the combination values of NT-proBNP and ***:Baseline GDF-15 and NT-proBNP were significantly higher amongst deceased than those in survivors(P<0.001).In ROC analyses,area under curve(AUC)for GDF-15 to predict 1-year mortality was 0.707(95%confidence interval[CI]:0.648–0.762,P<0.001),and for NT-proBNP was 0.682(95%CI:0.622–0.738,P<0.001).No statistically significant difference was found between the two markers(P=0.650).Based on the optimal cut-offs(GDF-15:4526.0 ng/L;NT-proBNP:1978.0 ng/L),the combination of GDF-15 and NT-proBNP increased AUC for 1-year mortality prediction(AUC=0.743,95%CI:0.685–0.795,P<0.001).Conclusions:GDF-15,as a prognostic marker in patients with AHF,is not inferior to *** the two markers could provide an early recognition of high-risk patients and improve the prediction values of AHF long-term *** trial registration:ChiCTR-ONC-12001944,http://***.

关键词： growth differentiation factor-15 Heart failure N-terminal pro-B type natriuretic peptide Prognosis

growth and F_v/F_m in embryos of Hizikia fusiformis (Harvey) Okamura (Sargassaceae,Phaeophyta) cultured under different temperature and irradiance conditions

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Journal of Oceanology and Limnology 2018年第5期36卷 1798-1805页

作者： WANG Longle ZHANG Xin ZOU Dinghui CHEN Weizhou JIANG Heng School of Environment and Energy South China University of TechnologyGuangzhou 510006China The Science and Technology Division South China University of TechnologyGuangzhou 510006China The Key Lab of Pollution Control and Ecosystem Restoration in Industry Clusters Ministry of EducationGuangzhou 510006China Marine Biology Institute Science CenterShantou UniversityShantou 515063China

Understanding the embryo physiology of Hizikia fusiformis（Harvey） Okamura will promote the development of artificial seedlings. In this study, H. fusiformis embryos were cultured under different environmental conditions, including different temperatures（15℃, 20℃, and 25℃）, sunlight intensities（100%, 50%, and 25% of full solar radiation） and types of UVR（UV-A and UV-B）. Then, we determined the lengths, maximal quantum yields（ Fv/Fm）, and survival rates of the embryos. The results showed that the embryos had the highest lengths, Fv/Fm values and survival percentages when cultured under a temperature of 20℃ and 25% sunlight intensity. The full level of solar radiation severely reduced the growth and survival ratios of the embryos. Hizikia embryos recovered within 2 h from the damage caused by short-term（30 min） high radiation（about 70% of full solar radiation） and UVR exposure. However, the viabilities of the embryos were significantly decreased after 4 h exposure to UVR. According to these results, we propose that culture conditions with indoor natural light and room temperature would be favorable for the growth, development and physiology of H izikia embryos.

关键词： Hizikia fusiformis embryos growth Fv/Fm temperature irradiance

growth and Wood/Bark Properties of Abies faxoniana Seedlings as Affected by Elevated CO_2

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Journal of Integrative Plant Biology 2008年第3期50卷 265-270页

作者： Yun-Zhou Qiao Yuan-Bin Zhang Kai-Yun Wang Qian Wang Qi-Zhuo Tian Chengdu Institute of Biology the Chinese Academy of Sciences Chengdu 610041 China Shanghai Key Laboratory of Urbanization Processes and Ecological Restoration East China Normal University Shanghai 200062 China Agronomic College Shandong Agricultural University Taian 271018 China

growth and wood and bark properties of Abies faxoniana seedlings after one year＇s exposure to elevated CO2 concentration （ambient ＋ 350 （± 25） μmol/mol） under two planting densities （28 or 84 plants/m^2） were investigated in closed-top chambers. Tree height, stem diameter and cross-sectional area, and total biomass were enhanced under elevated CO2 concentration, and reduced under high planting density. Most traits of stem bark were improved under elevated CO2 concentration and reduced under high planting density. Stem wood production was significantly increased in volume under elevated CO2 concentration under both densities, and the stem wood density decreased under elevated CO2 concentration and increased under high planting density. These results suggest that the response of stem wood and bark to elevated CO2 concentration is density dependent. This may be of great importance in a future CO2 enriched world in natural forests where plant density varies considerably. The results also show that the bark/wood ratio in diameter, stem cross-sectional area and dry weight are not proportionally affected by elevated CO2 concentration under the two contrasting planting densities. This indicates that the response magnitude of stem bark and stem wood to elevated CO2 concentration are different but their response directions are the same.

关键词： Abies faxoniana seedling growth industrial production stem bark stem wood density