检索结果-南通市图书馆

North Pacific sea ice cover, a predictor for the Western North Pacific typhoon frequency?

在线全文

学校读者我要写书评

暂无评论

Science china Earth sciences 2007年第8期50卷 1251-1257页

作者： FAN Ke institute of Atmospheric Physics, chinese Academy of {2., Beijing 10002., china Department of Atmospheric Science, Yun-nan University, kunming 650091, china 1. institute of Atmospheric Physics Chinese Academy of Sciences Beijing 100029 China 2. Department of Atmospheric Science Yunnan University Kunming 650091 China

The relationship between the sea ice cover in the North Pacific and the typhoon frequency has been studied in this paper. It follows that the index for the sea ice cover in the North Pacific (ISA) both in December-January-February (DJF) and in March-April-May (MAM) is negatively correlated with annual typhoon number over the western North Pacific (TNWNP) during 1965―2.04, with correlation coeffi-cients of -0.42.and -0.49 respectively (above 99% significant level). Large sea ice cover in the North Pacific tends to decrease TNWNP. Positive ISA (MAM) is associated with the tropical circulation and SST anomalies in the North Pacific, which may lead to unfavorable dynamic and thermal conditions for typhoon genesis over WNP from June to October (JJASO). The variability of the atmospheric circula-tion over the North Pacific, associated with the ISA anomaly in MAM is connected to the tropical at-mospheric circulation variability in MAM via the teleconnection wave train. Besides, as the tropical circulation has strong seasonal persistency from the MAM to JJASO, thus, the ISA in MAM-related variability of the tropical atmospheric circulation as well as the SST can affect the typhoon activity over the western North Pacific.

关键词： typhoon sea ice cover North Pacific teleconnection

Comparative study of pollination biology of two closely related alpine Primula species,namely Primula beesiana and *** (Primulaceae)

在线全文

学校读者我要写书评

暂无评论

Journal of Systematics and Evolution 2010年第2期48卷 109-117页

作者： 1,2.hi-Kun WU 1Chang-Qin ZHANG 1(kunming institute of Botany,{2. Academy of sciences,kunming 6502.4,china) 2.Graduate School of {2. Academy of sciences,Beijing 100049,china) (kunming institute of Botany Chinese Academy of Sciences Kunming 650204 China) (Graduate School of chinese Academy of sciences Beijing 100049 China) *Correspondence: Chang-Qin ZHANG *Correspondence: *?Author for correspondence. E-mail: zhangchangqin@*** Tel.: 86-871-52.-3630 Fax: 86-871-52.-6345.

The comparative pollination biology of a population of Primula beesiana,a population of ***,and an overlapping population of these two species in Yulong Shan,yunnan Province,china,was studied in 2.04 and *** results indicate that both *** and *** are typical heterostylous and obligate outcrossing species;the main pollinators of the two species were bees and *** the sites of all three populations,the main pollinating visitors of the two species showed preference for one of the two species,resulting in the ethological isolation of the two species by the *** ethological isolation contributes to the reproductive isolation of the two species,which supports the hypothesis that *** and *** are two distinct *** reproductive isolation of the two species (ethological isolation) is probably an important mechanism in maintaining species boundaries in the genus and has contributed to the species diversification of Primula in the *** addition,gene exchanges between *** and *** has occurred to some extent in the overlapping population,but whether natural hybridization has contributed to species diversification in Primula remains to be determined.

关键词： pollination biology Primula beesiana Primula bulleyana reproductive isolation

Diacylated Triterpenoid Saponin from Silene szechuensis

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

chinese Chemical Letters 1999年第1期10卷 33-36页

作者： Cheng ZOU Jia Xiong JIANG Chang Xiang CHEN Jun ZHOU Qing ZHAO(Faculty of Pharmacy, kunming Medical College, kunming 650031)(kunming institute of Botany, the chinese Academy of sciences, kunming 6502.4)(yunnan College of Traditional chinese Medicine. Ku kunming Med Coll Fac Pharm Kunming 650031 Peoples R China chinese Acad Sci Kunming Inst Bot Kunming 650204 Peoples R China yunnan Coll Tradit chinese Med Kunming 650011 Peoples R China

A new triterpenoid saponin, named silenoside, with sugar chains esterified by two different acyl groups was isolated from Silene szechuensis. Its structure was elucidated by chemical and spectral methods.

关键词： silenoside acylated triterpenoids saponin Silene szechuensis

Stable RNA hairpins in 88 coding regions of human mRNA

在线全文

学校读者我要写书评

暂无评论

Progress in Natural Science:Materials International 2004年第11期 24-29页

作者： PAN Min 1*, WANG Chuanming 1* and LIU Ciquan 1,2.3**(1. Modern Biological Center, yunnan University, kunming 650091,{2. 2. kunming institute of zoology, chinese Academy of sciences, kunming 6502.3,{2. 3. Center for Theoretical Biology, Peking University, Beijing 100871,{2.) ModernBiologicalCenter YunnanUniversityKunming650091China CenterforTheoreticalBiology PekingUniversityBeijing100871China

RNA hairpins containing UNCG, GNRA, CUUG (N=A, U, C or G, R=G or A) loops are unusually thermodynamic stable and conserved structures. The structural features of these hairpin loops are very special, and they play very important roles in vivo. They are prevalent in rRNA, catalytic RNA and non-coding mRNA. However, the 5′ C(UUCG)G 3′ hairpin is not found in the folding structure of 88 human mRNA coding regions. It is also different from rRNA in that there is no preference for certain sequences among tetraloops in these 88 mRNA folding structures.

关键词： thermodynamic stability hairpin UNCG GNRA RNA structure.

An orbital period investigation of the Algol-type eclipsing binary VW Hydrae

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

chinese Journal of Astronomy and Astrophysics 2009年第3期9卷 307-314页

作者： Jia Zhang Sheng-Bang Qian Boonrucksar Soonthomthum National Astronomical Observatories/yunnan Observatory Chinese Academy of Sciences Kunming 650011 China Graduate School of the chinese Academy of sciences Beijing 100039 China National Astronomical Research institute of Thailand/Ministry of Science and Technology Bangkok Thailand

Orbital period variations of the Algol-type eclipsing binary, VW Hydrae, are analyzed based on one newly determined eclipse time and the other times of light minima collected from the literature. It is discovered that the orbital period shows a continuous increase at a rate ofdP/dt = ＋6.34 × 10^-7 d yr^-1 while it undergoes a cyclic change with an amplitude of 0.0639 d and a period of 51.5 yr. After the long-term period increase and the large-amplitude period oscillation were subtracted from the O-C curve, the residuals of the photoelectric and CCD data indicate a small-amplitude cyclic variation with a period of 8.75 yr and a small amplitude of 0.0048 d. The continuous period increase indicates a conservative mass transfer at a rate of dM2.dt = 7.89 × 10^-8 M⊙ yr^-1 from the secondary to the primary. The period increase may be caused by a combination of the mass transfer from the secondary to the primary and the angular momentum transfer from the binary system to the circumbinary disk. The two cyclic period oscillations can be explained by light-travel time effects via the presence of additional bodies. The small-amplitude periodic change indicates the existence of a less massive component with mass M3 〉 0.53 M⊙, while the large-amplitude one is caused by the presence of a more massive component with mass M4 〉 2.84M⊙. The ultraviolet source in the system reported by Kviz ＆ Rufener （1987） may be one of the additional components, and it is possible that the more massive one may be an unseen neutron star or black hole. The rapid period increase and the possibility of the presence of two additional components in the binary make it a very interesting system to study. New photometric and high-resolution spectroscopic observations and a detailed investigation of those data are required in the future.

关键词： stars binaries close - stars binaries eclipsing - multiple stars - stars individual (VW Hya)

Activation of biomass-derived porous carbon for supercapacitors:A review

在线全文

学校读者我要写书评

暂无评论

chinese Chemical Letters 2024年第7期35卷 121-138页

作者： Zixuan Guo Xiaoshuai Han Chunmei Zhang Shuijian He kunming Liu Jiapeng Hu Weisen Yang Shaoju Jian Shaohua Jiang Gaigai Duan Jiangsu Co-Innovation Center of Efficient Processing and Utilization of Forest Resources International Innovation Center for Forest Chemicals and MaterialsCollege of Materials Science and EngineeringNanjing Forestry UniversityNanjing 210037China institute of Materials Science and Devices Suzhou University of Science and TechnologySuzhou 215009China Faculty of Materials Metallurgy and Chemistry Jiangxi University of Science and TechnologyGanzhou 341000China Fujian Provincial Key Laboratory of Eco-Industrial Green Technology Key Laboratory of Green Chemical Technology of Fujian Province UniversityCollege of Ecological and Resources EngineeringWuyi UniversityWuyishan 354300China

Due to the advantages of renewable,low pollution and wide distribution of biomass resources,it is selected as the electrode material for *** carbon-based electrode materials,specific surface area and pore structure have a great *** and summarizing the influence of activation on pore structure will greatly broaden this *** on the activation mechanism of activator,this paper summarizes the latest progress of biomass activation applied to supercapacitors,including traditional physical and chemical activation methods and non-traditional methods such as biological activation method,self-activation method,template assisted activation method and green activator ***,the challenges,strategies and prospects for the future development of biomass-derived carbon material activation are pointed *** summary,this review will help researchers choose appropriate strategies to design biomass-derived carbon electrode materials for supercapacitors,thereby promoting the application of biomass materials.

关键词： Biomass-derived Activation Pore structure Electrochemistry Supercapacitor

Effects of copper-aspirin complex on platelet-neutrophil interactions

在线全文

学校读者我要写书评

暂无评论

Acta Pharmacologica Sinica 2004年第5期25卷 34-38页

作者： Zhi-qiang SHEN2. Peng CHEN3, Ling LI, Peng CHEN, Wei-ping LIU4yunnan Pharmacological Laboratories of Natural Products, kunming Medical College, kunming 650031, china 3kunming Shenghuo Pharmaceutical Ltd Co, kunming 6502.7 4kunming institute of Precious Metals, kunming 6502.1, china. yunnan Pharmacological Laboratories of Natural Products Kunming Medical College kunming Shenghuo Pharmaceutical Ltd Co kunming institute of Precious Metals

AIM: To investigate the effects of copper-aspirin complex on rat thrombosis and the interaction between plateletsand neutrophils. METHODS: The model of electrically stimulated carotid artery thrombosis in Sprague Dawleyrats was used; the effects of copper-aspirin complex on rat platelet-neutrophil adhesion and platelet aggregationstimulated by activated neutrophils were observed by rosette assay and Borns method, respectively. RESULTS:Intragastric copper-aspirin complex (5, 7, and 10 mg/kg) dose-dependently prolonged the occlusion time; it signifi-cantly decreased the rosette number formed between thrombin-activated platelets and neutrophils; the 50 % ofinhibitory concentration (IC50) was (54.64.3) mol/L. Copper-aspirin complex markedly inhibited rat plateletaggregation induced by either cell free supernatant of activated neutrophils or by activated neutrophil *** values of IC50 were (2.4.516.2. mol/L and (82..52..4) mol/L, whereas aspirin had no ***: Copper-aspirin complex inhibited platelet-neutrophil interactions through a different property fromaspirin and resulted in a more potent antithrombotic activity.

关键词： copper aspirin thrombosis platelets neutrophils adhesion platelet aggregation

Fuzzy interface treatment in Eulerian method

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Science china(Technological sciences) 2004年第5期47卷 550-568页

作者： NING Jianguo1 & CHEN Longwei1,2.1. National Key Laboratory of Protection and Control of Explosive Disaster, Beijing institute of Technology, Beijing 100081, china 2. The Faculty of Land Resource Engineering, {2. University of Science and Technology, {2. 650093, china Correspondence should be addressed to Ning Jianguo 1. National Key Laboratory of Protection and Control of Explosive Disaster Beijing Institute of Technology 100081 Beijing China 2. The Faculty of Land Resource Engineering Kunming University of Science and Technology 650093 Kunming China

In this paper, we incorporate fuzzy mathematics approach into the Eulerian method to simulate three dimensional multi-material interfaces. In particular, we propose a fuzzy interface treatment for describing interfaces, designing transport plans, and computing transport quantities. Using a set of three-dimensional inviscid isothermal elastic-plastic hydrodynamic equations, we simulate shaped charge jet in different filled dynamite structures. Strain and stress have been under consideration in simulations. Numerical results demonstrate that the fuzzy interface treatment is correct and efficient for three-dimensional multi-material problems.

关键词： Eulerian method, multi-material, fuzzy interface, shaped charge jet, three-dimensional numerical simulation.

A Further Research on the Precambrian-Cambrian Boundary at Meishucun Section of Jinning, yunnan, china

在线全文

学校读者我要写书评

暂无评论

Acta Geologica Sinica(English Edition) 1992年第2期66卷 197-207页

作者： Luo Huilin Jiang Zhiwen Wu Xiche Ouyang Lin Song Xueliang Xue Xiaofeng yunnan institute of Geological {2., kunming, yunnan yunnan institute of Geological {2. Kunming Yunnan

This paper gives a brief report on the latest results in litho-, bio-, and chrono-stratigraphy obtained fromthe authors' further research on the Meishucun section during 1987-1988. More attention was paid to the studyof the microtexture of Lapworthella and some new materials of trace fossils. Phycodes pendum Seilacher, animportant index for correlation, was also discovered in the Zhongyicun Member. In the Yu' anshan Membermany worms, medusas and arthropods of the Chengjiang fauna have been found by other workers. Asupplemental study was made on the fossil zones of the Meishucunian stage. Based on new isotopic data, theage of the Precambrian-Cambrian boundary should now be 597 Ma. It is further suggested that point 'B' re-mains as an optimum selection for defining the Precambrian-Cambrian boundary.

关键词： china A Further Research on the Precambrian-Cambrian Boundary at Meishucun Section of Jinning