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1.
lar Fraction Developing Anti-endotoxin Activity of F_(022) from Radix IsatidisLIN Ai-hua~1,LIU Yi-ming~1,QIU Xiao-hui~1,LIU Yun-hai~2(1.The Second Affiliated Hospital of Guangzhou University of TCM,Guangzhou 510120,China;2.Tongji Hospital,Tongji Medical College of Huazhong University of Science and Technology,Wuhan 430030,China  相似文献   

2.
The interdecadal variation of coral grayness in northern South China Sea (SCS) is studied using the annual mean coral grayness in northern SCS from 1789 to 1992 and annual precipitation at Guangzhou from 1908 to 1992 by Singular Spectrum Analysis (SSA), correlation analysis, Mann-Kendalrs abrupt change analysis and composite analysis. The interdecadal variation of south China precipitation as reflected by the series of Guangzhou precipitation rebuilt with the coral grayness is discussed. The results show that the variation of coral grayness in SCS has significant terms of tendency, much-weighted interdecadal variation and weak interannual variation. There was a century-scale abrupt change of coral grayness at the end of the 1880s that changed from positive anomalies to negative anomalies. The global field of SST difference corresponding to the point of abrupt change was negative anomalies over the SCS and neighboring northern Indian Ocean, most of central and western Pacific Ocean and coastal areas of the northern Atlantic Ocean. The large-scale distribution of SST anomalies is concomitant with the century-scale abrupt change of coral grayness in SCS. Negative correlation exists between the coral grayness in SCS and precipitation in Guangzhou on the interdecadal scale and the interdecadal precipitation in Guangzhou as reflected by the interdecadal data of SCS coral grayness shows that the interdecadal variation of south China precipitation changes significantly from phase to phase. The current study aims at contributing in the effort of identifying alternative indexes for climate change in south China on the interdecadal scale and beyond.  相似文献   

3.
《科学通报(英文版)》2011,56(23):2518-2518
The Institute of Polymer Optoelectronic Materials & Devices, South China University of Technology, Guangzhou, in close collaboration with the Department of Electrical and Electronic Engineering, The University of Hong Kong, has shown that the band gap and energy  相似文献   

4.
INTRODUCTIONEka Chemicals, Sweden, and State Key Laboratory of P & P Engineering (SKLPPE), Guangzhou, China, are involved in a joint project to investigate different methods of bleaching non-wood fibres with the aim of achieving more efficient utilisation of domestic fibre resources, improving the quality of bleached pulp / final product and of satisfying the requirements for the protection of the environment. The results from bleaching non-wood fibres applying TCF (OQP) and CEH …  相似文献   

5.
China's sizeable and uncertain carbon sink: a perspective from GOSAT   总被引:1,自引:0,他引:1  
Despite the agreement that China’s terrestrial ecosystems can provide a carbon sink and offset carbon dioxide(CO2)emissions from fossil fuels,the magnitude and spatial distribution of the sink remain uncertain.Accurate quantification of the carbon sequestration capacity of China’s terrestrial ecosystems has profound scientific and policy implications.Here,we report on the magnitude and patterns of China’s terrestrial carbon sink using the global monthly CO2flux data product from the Greenhouse gases Observing SATellite(GOSAT),the world’s first satellite dedicated to global greenhouse gas observation.We use the first year’s data from GOSAT(June 2009–May2010)that are currently available to assess China’s biospheric carbon fluxes.Our results show that China’s terrestrial ecosystems provide a carbon sink of-0.21 Pg C a-1.The consumption of fossil fuels in China leads to carbon dioxide emissions of 1.90 Pg C a-1into the atmosphere,approximately 11.1%of which is offset by China’s terrestrial ecosystems.China’s terrestrial ecosystems play a significant role in offsetting fossil fuel emissions and slowing down the buildup of CO2in the atmosphere.Our analysis based on GOSAT data offers a new perspective on the magnitude and distribution of China’s carbon sink.Our results show that China’s terrestrial ecosystems provide a sizeable and uncertain carbon sink,and further research is needed to reduce the uncertainty in its magnitude and distribution.  相似文献   

6.
Based on the nonlinear Lyapunov exponent and nonlinear error growth dynamics, the spatiotemporal distribution and decadal change of the monthly temperature predictability limit (MTPL) in China is quantitatively analyzed. Data used are daily temperature of 518 stations from 1960 to 2011 in China. The results are summarized as follows: (1) The spatial distribution of MTPL varies regionally. MTPL is higher in most areas of Northeast China, southwest Yunnan Province, and the eastern part of Northwest China. MTPL is lower in the middle and lower reaches of the Yangtze River and Huang-huai Basin. (2) The spatial distribution of MTPL varies distinctly with seasons. MTPL is higher in boreal summer than in boreal winter. (3) MTPL has had distinct decadal changes in China, with increase since the 1970s and decrease since 2000. Especially in the northeast part of the country, MTPL has significantly increased since 1986. Decadal change of MTPL in Northwest China, Northeast China and the Huang-huai Basin may have a close relationship with the persistence of temperature anomaly. Since the beginning of the 21st century, MTPL has decreased slowly in most of the country, except for the south. The research provides a scientific foundation to understand the mechanism of monthly temperature anomalies and an important reference for improvement of monthly temperature prediction.  相似文献   

7.
The analysis of carbon isotope in phytoliths from modern plants and surface soils in China shows that the values of carbon isotope are consistent with those from C3 and C4 plants,and the processes of photosynthesis of the original plants can be clearly identified by carbon isotope in phytoliths.The value of carbon isotope varied from -23.8‰ to -28‰,with the maximum distributed in the latitude zone from 34° N to 40° N in North China and East China areas,and the minimum in the Northeast China and South China regions.The values of carbon of phytoliths tend to increase from low to high and then reduce to low value again as the latitude increases.In the same latitude zone,the carbon isotope in phytoliths from grassland soil under the trees is obviously lower than that from grassland soil without any trees with the difference of 1‰-2‰.  相似文献   

8.
Study on the Capture of Spectral Information of Laccase-Catalyzed Intermediate in Reversed Micelles and Its Resolution LIU Zhi-hong~(1,2),SHEN Ping~2,CAI Ru-xiu~1 (1.College of Chemistry and Molecular Sciences,Wuhan University,Wuhan 430072,Hubei,China; 2.College of Life Sciences,Wuhan University,Wuhan 430072,Hubei,China) Abstract:The kinetic spectrum of the intermediate of laccase-catalyzed reaction was captured by making  相似文献   

9.
IntroductionBeijing is the national capital of China,andthe capital of Beijing Municipality. The city islocated on the North China Plain,approximately1 50 km Northwest of the Bohai Sea at a north-latitude of40°.The municipality is approximately1 60 0 0 km2 in size,of which 2 / 3is mountainousarea encircling the western,northern and easternsides of the city. From the 1 990 census,the totalpopulation was 1 2 .9million,with 6. 4millionliving in urban areas,5.2 million living in the city,and …  相似文献   

10.
The tectonic setting of the west region of the Reserved Area of the International Seabed Authority is the same as that of China Pioneer Area. They have similar characteristics of topography and nodule distribution. To research and analyse the characteristics and control factors of nodule distribution can help the establishment of a geological model and the assessment of the polymetallic nodule resource. From the year of 1991 till 2000 COMRA (China Ocean Mineral Resource Research and Development Association) carried out phase 1 and 2 of the exploration and resource assessment project of polymetallic nodules in China Pioneer Area. The features of topography and geology, and the distribution of polymetallic nodules and control factors have been clearly understood. The results show that the formation and types and spatial features of abundance and grade of nodules resulted from several factors, the tectonic features (volcanism and faulting)and seafloor topography play an important role in the geological process of the formation of polymetallic nodules.  相似文献   

11.
图集的统一协调,对图集质量有很大影响。本文是作者在编制北京市农业区划地图集的实践基础上,根据地图信息传输论的观点,对农业区划地图集的统一协调的内容及方法进行了探讨。试图总结编制这类图集的统一协调模式,以供读者编图时参考。  相似文献   

12.
研究了国家法的抽象正义观与民间法的情理正义观,认为西方国家法的抽象正义观与东方民间法的情理正义观存在实质的不同,原因在于思维方式、超验与经验传统、政治结构的差别。在现代法治理念下,传统民间法所代表的正义观将向混合正义观转型,西方法治所代表的国家法抽象正义观是其骨架。  相似文献   

13.
给出了一维非自治时滞系统点态退化的一个例子,拓宽了该领域的研究。  相似文献   

14.
利用对位异构体的对称性由核磁共振氢谱测定了工业十二烷基苯在硝硫混酸中的硝化选择性,发现一硝化产物中对位异构体的比例为75% ̄80%。以月桂酸和苯为原料,经氯化、酰化和还原合成了正十二烷基苯。在同样条件下研究了正十二烷基苯的硝化,由核磁共振氢谱和气相色谱分析,发现一硝化产物中对位异构体的比例仅为60%。根据空间位阻效应,对结果进行了讨论,并与甲苯,乙苯,异丙苯等短链烷基苯的硝化结果进行了比较。  相似文献   

15.
YBCO掺杂效应研究   总被引:3,自引:0,他引:3  
介绍了YBCO掺杂的基础知识,总结了YBCO各个位置采用典型元素掺杂而导致的超导电性和结构的变化,阐述了掺杂对YBCO的重要影响,并简介了当前YBCO掺杂效应研究中的几个热点问题.  相似文献   

16.
由于有限群的Lagrange定理的逆不成立,因此,n较大时要确定n次交代群An的所有子群或对An阶数的每一个正因数,确定是否存在这个阶数的子群是较困难的问题.文章通过对5-循环置换各次方幂的计算及其研究,构造出了A5的5个12阶子集,并证明了每一个子集都是A5的12阶子群,最后对A5的部分阶的子群做了总结.  相似文献   

17.
18.
为了找出诱发高频机组基础不良振动的原因,从基础计算模型方面对基础激励与响应进行了分析,以两个高频机组基础为动测实例,经模态分析得出钢筋混凝土构架式基础竖向1阶振动与电机产生共振;应用功率谱法对动力机组及基础平台进行动测,得出平台异常响应频率66Hz为水泵工作频率,调整机器的工作频率可避开不良振源影响,达到明显的减振效果。由此而知,动力机器基础出现不良振动时,不可盲目改变结构的动力特性,应在机器不同工况比如:停机、起机及正常转速下,对机器及基础进行动测并对振动信号进行比较分析,以制定出行之有效的减振方法。  相似文献   

19.
基于“前沿分支”的观点研究了圈幂补图的树宽,首先确定了它的树宽下界,又给出了达到此下界的标号,从而得到了它的树宽表达式。  相似文献   

20.
报告鸡法氏囊病的流行状况,主要症状,剖检情况及诊断,提出了综合性防治措施。  相似文献   

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