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Influence of the North American Dipole on ENSO onset as simulated by a coupled ocean-Atmosphere model

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Atmospheric and Oceanic Science Letters 2021年第6期14卷 1-6页

作者： Jinghua Chao guangzhou Fan Ruiqiang Ding School of Atmospheric Sciences Chengdu University of Information TechnologyChengduChina State Key Laboratory of Earth Surface Processes and Resource Ecology Beijing Normal UniversityBeijingChina

The North American Dipole(NAD)is a north-south seesaw pattern of sea level pressure anomalies over the western tropical North Atlantic and northeastern North *** observational studies have demonstrated that the NAD can affect the outbreak of El Niño-Southern Oscillation(ENSO)*** present study analyzed the NAD-ENSO relationship as simulated by a coupled ocean-atmosphere model-namely,the Flexible Global Ocean-Atmosphere-Land System model,gridpoint version 2(FGOALS-g2).Results indicated that the model can replicate a distinct dipole comprised of a low over northeastern North America and a high over the western tropical North Atlantic,which is the signature feature of the *** analysis verified that the winter NAD can initiate the central equatorial Pacific warming in the subsequent winter by effectively forcing an anticyclonic flow and sea surface temperature(SST)warming over the northeastern subtropical Pacific(NESP)during late winter or early *** addition,the probability of an El Niño event was increased by a factor of 1.8 in the assimilation experiment with the *** comparison,the winter Northern Atlantic Oscillation had no significant impact on the occurrence of ENSO a year later owing to its failure to induce the SST and surface wind anomalies over the NESP.

关键词： North American Dipole ENSO Coupled ocean-atmosphere model

Abnormal Blood Glucose Concentration on Degradation Behavior of AZ31 Magnesium Alloy

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Chemical Research in Chinese Universities 2020年第6期36卷 1217-1226页

作者： LI Zhihui GUO Xiaotong ZHANG Yaning LIU guangzhou ZHANG Shuyong School of Chemistry and Chemical Engineering Shandong UniversityJinan 250100P.R.China Institute of Marine Science and Technology Shandong UniversityQingdao 266237 P.R.China

In order to evaluate the effect of blood glucose concentration on the reliability of AZ31 magnesium alloy medical implant,the corrosion of AZ31 alloy was studied in a simulated physiological saline *** is found that when the glucose concentration is in the normal range of ca.1g/L,the corrosion of AZ31 alloy can be inhibited However,when the glucose concentration becomes higher like that of diabetic patients,the degradation of AZ31 alloy is significantly ***,for diabetic patients,the change in glucose concentration must be taken into consideration in order to ensure the reliability ofAZ31 medical implants.

关键词： Medical implant material AZ31 magnesium alloy Degradation Blood glucose Hyperglycemia

ON CLASSIFICATION OF PROJECTIVE VARIETIES WITH NON-INTEGRAL NEF VALUES

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Chinese Annals of Mathematics,Series B 2001年第2期22卷 255-262页

作者： ZHAO YICAI Department of Mathematics, Jinan University, guangzhou 510632, China. Department of Mathematics Jinan University Guangzhou 510632 China

Let M be an n-dimensional normal projective variety with only Gorenstein, terminal, Qfactorial singularities. Let L be an ample line bundle on M. Let r denote the nef value of (M, L). The classification of (M, L) via ... 详细信息

关键词： Nef value morphism Ample line bundle Projective variety

Magnetic properties of Jiaxian red clay sequences from northern Chinese Loess Plateau and its paleoclimatic significance

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Science China Earth Sciences 2005年第8期48卷 1234-1245页

作者： QIANG Xiaoke, AN Zhisheng, LI Huamei, CHANG Hong & SONG Yougui 1. SKLLQG, Institute of Earth Environment, Chinese Academy of Sciences, Xi’an 710075, China 2. guangzhou Institute of Geochemistry, Chinese Academy of Sciences, guangzhou 51064., China Chinese Academy of Sciences SKLLQG Institute of Earth Environment Xi’an China Chinese Academy of Sciences Guangzhou Institute of Geochemistry Guangzhou China

Detailed rock magnetism investigation of the Jiaxian red clay sequences indicated that there are common magnetic mineralogy properties in red clay and loess-paleosol sequences from the Chinese Loess Plateau as well as the marked properties of themselves, magnetic min-erals mainly with magnetite, maghemite, hematite, and possibly limonite/goethite contributing to the magnetic behavior. Meanwhile, it is found that the strong paleosol in red clay sequences has a lower coercivity and higher content of ultra-fine ferrimagnetic grains than that of the weak pa-leosol, which is similar to loess and paleosol in upper Wucheng Loess sequences, and indicates that humid conditions and relatively strong pedogenesis play a significant role in the increase of ultra-fine magnetic minerals and transformation of the magnetic minerals. This suggests that, like Quaternary loess-paleosols, the change of characteristics of paleoclimatic conditions of the late Tertiary red clay deposits is fluctuant. In addition, the results of magnetic hysteresis properties show that the applied saturated field for samples from the Jiaxian red clay sequences is higher than that of the samples from eastern and southern Chinese Loess Plateau. It is obviously shown that there exist more hard magnetic minerals and relatively weak biochemical processes in the Jiaxian red clay sequences on northern Chinese Loess Plateau. We conclude that the paleocli-matic environment is different between northern and eastern/southern Chinese Loess Plateau, and it should be more arid in northern Chinese Loess Plateau.

关键词： northern Chinese Loess Plateau, red clay, magnetic property, paleoclimatic significance.

Comparative studies on zooplankton community between the sea surface microlayer and the subsurface microlayer in Daya Bay, China

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Progress in Natural Science:Materials International 2005年第8期15卷 713-719页

作者： YANG Yufeng*(Institute of Hydrobiology, Jinan University, guangzhou 510632, China) Institute of Hydrobiology Jinan University Guangzhou 510632 China

Characteristics of the zooplankton community inhabiting the sea surface microlayer (SM) and the sub-surface microlayer (SSM) are compared at six sampling stations in Daya Bay, near Shenzhen City of China during 2 cruises in 1999. This is the first study on zooplankton community in the SM in China. Results show that protozoans and nauplii are the most dominant components, accounting for 80.71% (SM) and 89.15% (SSM) of the total zooplankton in the average abundance, respectively. The densities of copepods (adult + copepodid) are higher in the SSM than in the SM. The size-frequency distributions indicate that the frequency of micro-zooplankton (<0.2 mm) is higher in the SM (0.8235, n=290) than in the SSM (0.6768, n=306). Enrichment phenomenon of zooplankton is detected in the SM at the sampling stations excluding two stations near nuclear power plants (NPP). The enrichment factor is from 1.516 to 3.364 with the average value of 2.267. The SM zooplankton community structure revealed in the present study is quite different from previous investigations in the Bay. Typical sea water characteristics such as turbidity, biological oxygen demand (BOD), chemical oxygen demand (COD), total nitrogen (TN), total phosphorus (TP) and chlorophyll a (Chl-a) indicate that the water quality is poorer in the SM than in the SSM.

关键词： zooplankton density sea surface microlayer subsurface microlayer Daya Bay.

On the Federalism Corporate Law

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学术界 2011年第1期 262-264页

作者： Zuo Chuanwei guangzhou University

Some scholars in our country conclude that the federalism corporate law model is one of the most important factors for the rise of American corporate system and its socialprosperity;accordingly,they advocate that our corporate legislation model should be decentral ization so as to stimulate corporate system’s social function as a kind of legal *** recommendation is based on different demands caused by local unbalanced development,factual decentralization between central authority and local government,and the lower efficiency of the united corporate *** the developing history of corporate system shows that only after democratization against privileges has been completed under the influence of democratic politics can corporate operate liberalization exert its social function which is the legal possibility of federalism corporate *** with problems and causations in our corporate system,the federalism corporate law in our country may be only a distant landscape.

关键词： corporate legislation federalism democratization

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 51064. (China) 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 51064. China The Institute of Polymer Science, Zhongshan University guangzhou 510275, China 华南理工大学广东广州中山大学广东广州

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

Derivation and characterization of human embryonic stem cell lines from poor quality embryos

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Journal of Genetics and Genomics 2009年第4期36卷 229-239页

作者： Weiqiang Liu, Yifei Yin, Xiaolin Long, Yumei Luo, Yonghua Jiang, Wenhong Zhang, Hongzi Du, Shaoying Li, Yuhong Zheng, Qing Li, Xinjie Chen, Baoping Liao, Guohong Xiao, Weihua Wang, Xiaofang Sun guangzhou Key Laboratory of Reproductive and Genetics Institute of Gynecology and Obstetrics, The Third Affiliated Hospital of guangzhou Medical College, guangzhou 510150, China guangzhou Key Laboratory of Reproductive and Genetic Institute of Gynecology and Obstetrics The Third Affiliated Hospital of Guangzhou Medical College Guangzhou China

Poor quality embryos discarded from in vitro fertilization （IVF） laboratories are good sources for deriving human embryonic stem cell （hESC） lines. In this study, 166 poor quality embryos donated from IVF centers on day 3 were cultured in a blastocyst medium for 2 days, and 32 early blastocysts were further cultured in a blastocyst optimum culture medium for additional 2 days so that the inner cell masses （ICMs） could be identified and isolated easily. The ICMs of 17 blastocysts were isolated by a mechanical method, while those of the other 15 blastocysts were isolated by immunosurgery. All isolated ICMs were inoculated onto a feeder layer for subcultivation. The rates of ICM attachment, primary ICM colony formation and the efficiency of hESC derivation were similar between the ICMs isolated by the two methods （P〉0.05）. As a result, four new hESC lines were established. Three cell lines had normal karyotypes and one had an unbalanced Robertsonian translocation. All cell lines showed normal hESC characteristics and had the differentiation ability. In conclusion, we established a stable and effective method for hESC isolation and culture, and it was confirmed that the mechanical isolation was an effective method to isolate ICMs from poor embryos. These results further indicate that hESC lines can be derived from poor quality embryos discarded by IVF laboratories.

关键词： embryonic stem ceils poor quality embryos inner cell mass mechanical isolation immunosurgery