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Nitric Oxide Emission Following Wetting of Dry Soils in Subtropical Humid Forests

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Pedosphere 2009年第6期19卷 692-699页

作者： LI De-Jun and WANG Xin-Ming 2 State Key Laboratory of Organic Geochemistry, guangzhou Institute of Geochemistry, Chinese Academy of Sciences, guangzhou 510640 (China) [a]State Key Laboratory of Organic Geochemistry Guangzhou Institute of Geochemistry Chinese Academy of Sciences Guangzhou 510640 (China)

Information about soil nitric oxide （NO） emissions from subtropical forests is quite limited, and even less is known about the pulse emission of NO when wetting soils after a long period of dryness. In this study, we measured NO fluxes following wetting of dry soft in a broadleaf forest and a pine forest in subtropical China. Large pulses of NO fluxes were observed after soil wetting in both forests. NO fluxes increased significantly within 0.5 h following wetting in both forests and reached peak 1 and 4 h after soil wetting in the pine forest and the broadleaf forest, respectively. In the broadleaf forest, averaged peak flux of NO pulses was 157 ng N m^-2 s^-1, which was 8 times the flux value before wetting, and in the pine forest, the averaged peak flux was 135 ng N m-2 s 1, which was 15.5 times the flux value before wetting. The total pulses-induced NO emissions during the dry season were roughly estimated to be 29.4 mg N m^-2 in the broadleaf forest and 22.2 mg N m^-2 in the pine forest or made up a proportion of 4.6% of the annual NO emission in the broadleaf forest and 5.3% in the pine forest.

关键词： dry season flux. NO. pulse subtropical China

SYNTHESIS AND OPTICAL PROPERTIES OF A NOVEL ORGANIC/INORGANIC HYBRID NONLINEAR OPTICAL POLYMER VIA SOL-GEL PROCESS

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Chinese Journal of Polymer Science 2001年第4期19卷 421-427页

作者： Hong-xia Xi Zhong Li Zhao-xi Liang The Institute of Chemical Engineering South China University guangzhou 510640 China The Institute of Polymer Science, Zhongshan University guangzhou 510275, China S China Univ Inst Chem Engn Canton 510640 Peoples R China Zhongshan Univ Inst Polymer Sci Canton 510275 Peoples R China

A new organic/inorganic hybrid nonlinear optical (NLO) material was developed by the sol-gel process of an alkoxysilane dye with tetraethoxysilane. A NLO moiety based on 4-nitro-4 ' -hydroxy azobenzene was covalently bonded to the triethoxysilane derivative, i.e, gamma -isocyanatopropyl triethoxysilane. The preparation process and properties of the sol-gel derived NLO polymer were studied and characterized by SEM, FTIR,H-1-NMR, UV-Vis, DSC and second harmonic generation (SHG) measurement. The results indicated that the chemical bonding of the chromophores to the inorganic SiO2 networks induces low dipole alignment relaxation and preferable orientational stability. The SHG measurements also showed that the bonded polymer film containing 75 wt% of the akoxysilane dye has a high electro-optic coefficient (r(33)) of 7.1 pm/V at 1.1 mum wavelength, and exhibit good SHG stability, the r(33) values can maintain about 92.7% of its initial value at room temperature for 90 days, and can maintain about 59.3% at 100 degreesC for 300 min.

关键词： sol-gel process nonlinear optical material alkoxysilane dye dipole alignment relaxation chromophore

THE REGIONAL DEVELOPMENT IN A MULTI-CULTURAL BACKGROUND──The Studies of Minority Regions in the Western China

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Chinese Geographical Science 2001年第2期11卷 168-173页

作者： LU La-chang (Department of Geography, guangzhou Normal University, guangzhou 510405, P. R. China) Department of Geography Guangzhou Normal University Guangzhou P. R. China

China is a country with many nationalities. Each of them has formed its own special culture, which is different from the mainstream of majority Han nationality, by adapting to geo-environment during history. Due to different backgrounds, the regional developmental model of minorities in the western China is different from the Han nationality and western countries. Combining a knowledge-based civilization and sustainable development, the minority areas can seek the systematic integration of culture-economy-ecology. Based on this, the paper suggests that the minority areas in western China should take the way of emphasizing developmental quality rather than developmental quantity for a harmonious system of culture-economy-ecology. Some approaches for developing minority areas in western China have been put foreword.

关键词： the minority regions in the western China multi-cultural background integrated model of economy-culture-ecology

西方古典美学的转折——克罗齐美学思想的历史地位与作用

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思想战线 2001年第2期27卷 82-85页

作者：王坤中山大学中文系!广东广州 510275

西方古典美学的转折 ,体现为三大方向 :美作为“心灵之花”———心理学美学 ;美作为实践活动之果———马克思主义美学 ;艺术作为独立之物———克罗齐美学。克罗齐美学思想的基点 ,是针对以黑格尔为代表的古典美学中的艺术消亡论 ,从... 详细信息

西方古典美学的转折 ,体现为三大方向 :美作为“心灵之花”———心理学美学 ;美作为实践活动之果———马克思主义美学 ;艺术作为独立之物———克罗齐美学。克罗齐美学思想的基点 ,是针对以黑格尔为代表的古典美学中的艺术消亡论 ,从逻辑的角度 ,论证了艺术是可以不依赖于理智而独立存在的。古典美学的三大转折方向 ,从拓宽美学研究领域角度看 ,心理学美学思潮的影响更大 ;从美学史上的实质性突破角度看 ,马克思主义实践论美学的意义与价值更大 ;从对现代美学发展的影响角度看 ,克罗齐艺术独立理论的作用更大

关键词：克罗齐美学古典美学现代美学艺术独立

Discussion on event horizon and quantum ergosphere of dynamic rotating black holes in a tunneling framework

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Chinese Physics B 2012年第7期21卷 162-167页

作者：刘佰生张靖仪 Center for Astrophysics Guangzhou University

According to the Parikh–Wilczek tunneling framework, the locations of the local horizons of dynamic rotating black holes can be worked out. The calculations show that the quantum ergosphere of the black hole is identical with the tunneling potential barrier set by particle’s tunneling across the relevant horizon. Then, some discussions on the origin of the Hawking radiation will be shown.

关键词： Hawking radiation dynamic rotating black holes tunneling framework quantum ergosphere

PREPARATION AND PROPERTIES OF ETHYL-CYANOETHYL CELLULOSE/POLYACRYLIC ACID COMPOSITE FILMS WITH REFLECTION COLORS

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Chinese Journal of Polymer Science 2001年第3期19卷 277-282页

作者： Yong Huang Institute of Chemistry, Chinese Academy of Sciences, Beijing 100080 China Laboratory of Cellulose and Lignocellulosics Chemistry guangzhou Institute of Chemistry Chinese Academy of Sciences, guangzhou 510650, China 中科院化学所北京

Ethyl-cyanoethyl cellulose [(E-CE)C]/acrylic acid (AA) becomes a cholesteric liquid crystalline solution withvivid colors when the (E-CE)C concentration is 42 wt%～52 wt%. (E-CE)C/polyacrylic acid (PAA) composites withcholesteric structure were prepared by polymerzing AA in (E-CE)C/AA liquid crystalline solutions. The layers of orderedpolymer chains in the cholesteric phase were inclined during polymerization and the degree of the inclination depended onthe polymerization temperature and the concentration of the solution before polymerization. The cholesteric structure in thecomposites could not be changed when temperature was lower than 100℃. Cross-linking of the PAA in compositesimproved their water-resistance. The cholesteric order of the composites without cross-linking was destroyed when theywhere immersed in water. The color derived from the selective reflection of the cholesteric phase of the cross-linkedcomposites turned from blue to red after the composites absorbed water. The color of the composites could be returned to theoriginal one when the absorbed water was removed from the swollen composites.

关键词： Cholesteric structure Composites Selective reflection Liquid crystalline solutions

Intravenous chemotherapy for resected gastric cancer:meta-analysis of randomized controlled trials

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World Journal of Gastroenterology 2002年第6期8卷 1023-1028页

作者： Jian-KunHu Zhi-xinChen Zong-guangzhou BoZhang JingTian Jia-Pin ChineseEvidence-BasedMedicine/CochraneCenter Chengdu610041SichuanProvinceChina GeneralSurgeryDepartment WestChinaHospitalofSichuanUniversityChengdu610041SichuanProvinceChina

AIM: To assess the safety and efficacy of different intravenous chemotherapeutic regimens in patiedts with gastric acrcinomas who had undergone gastrectomy.

关键词：胃肠癌切除手术后静脉内化疗随机控制试验主成分分析

Subtractive suppression hybridization combined with cDNA arrayScreening identifies differentially expressed genes between Micro- nucleates and amicronucleates of Pseudourostyla cristata

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Subtractive suppression hybridization combined with cDNA arr...

The Juancheng chondrite──A new meteorite falling recently in China

中国动物学会原生动物学分会第十二次学术讨论会

作者： Xinying Liu, Junjian Wang and Lipei Jin (Life School , Zhongshan University, guangzhou, prc 510275)

＜正＞ Based on morphologically comparative studies on amicronucleates and micronucleates of Pseudourostyla cristata, we supposed that the micronucleus absence may result in abnormal development of the subsurface cytoskeleton and/or other supportive elements in the vicinity of the AZM. To further provide insights into how micronucleus of P. cristata to regulate oral development, we employed suppression subtractive hybridization （SSH） and cDNA array to identify genes which express in micronucleate cells but not in amicronucleate cells.

关键词： Subtractive hybridization Amicronucleates Micronucleates cDNA array

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Chinese Science Bulletin 1998年第21期43卷 1834-1837页

作者： CHEN Yongheng 1,2, WANG Daode+2 and WANG Ruitian+31. Department of Chemistry, guangzhou Normal University, guangzhou 510400, China 2. guangzhou Institute of Geochemistry, Chinese Academy of Sciences, guangzhou 510640, China 3. Heze Bureau of Seismolo Department of Chemistry Guangzhou Normal University Guangzhou China guangzhou Institute of Geochemistry Chinese Academy of Sciences Guangzhou China Heze Bureau of Seismology Shandong Province Heze China

The Juancheng chondrite, a new meteorite falling recently in Juancheng County, Shandong Province, China, is classified as an H5 (S2) chondrite based on the compositions of olivine (Fa= 19.2, σ Fa=0.46) and low-Ca pyroxene (Fs=16.9, σ Fa=0.4). The plagioclase in the Juancheng chondrite is rich in CaO, indicating a relatively high metamorphic temperature the parent body underwent.

关键词： Juancheng ordinary chondrite new meteorite.