ISSUES ON CHINA′S ENERGY SECURITY

Energysupplyisadeterminantfactor to the developmentand the prosperity of a modern society. China is one ofthe largest energy consumers andproducersin the world,and energy supply and its security in the country aregreat issues concerned not onlybytheChina …     

EFFECTS OF WATER TABLE AND NITROGEN ADDITION ON CO_2 EMISSION FROM WETLAND SOIL

1IN T R O D U C T IO NCO2emissionfrom soiltoatmosphere,which isim por-tanttocontributetothecarbon balanceof ecosystem,isone of the largestfluxes in the global carbon cycle(SCHLESINGER and ANDREWS,2000).Further-more,thechange of CO2emission from soil,as a …     

模拟退火法反演远震P波波速慢度及方位数据求解长谷破火山口地壳速度结构

模拟退火法系一种非线性整体搜索算法,本文用以反演远震P波波速慢度和方位数据,求解地壳速度结构。综合试验表明,用模拟退火法能够以合理的精度确定P波低速带的空间位置,并能使近70％的目标速度扰动得以再现。实验表明,用少至两个台站的资料便可得到明显的结果。对长谷火山口的射线方向数据的反演发现,在8km深的再生穹丘构造以下存在一个不对称的低速带,相对背景波速有-25％的变动。这一低速带向东南延伸,深度至少达24km,其波速变动约为-10％。这些特征基本与远震走对的反演结果以及射线方向的正演模拟结果相一致,可能与长谷破火山口残余的岩浆房有关。     

Interstellar cyanomethane

We have made an observational study of the newly identified cyanomethane radical CH2CN and the possibly related species CH3CN with the goals of (1) elucidating the possible role of reactions of the type CnHm(+) + N in astrochemistry, and (2) providing a possible test of Bates's models of dissociative electron recombination. We find a remarkably different abundance ratio CH2CN/CH3CN in TMC-1 and Sgr B2, which we deduce is a result of the large difference in temperature of these objects. Studies of CH2CN and CH3CN in other sources, including two new detections of CH2CN, support this conclusion and are consistent with a monotonic increase in the CH2CN/CH3CN ratio with decreasing temperature over the range 10-120 K. This behavior may be explained by the destruction of CH2CN by reaction with O. If this reaction does not proceed, then CH2CN and CH3CN are concluded to form via different chemical pathways. Thus, they do not provide a test of Bates's conjectures (they do not both form from CH3CNH+). CH2CN is then likely to form via C2H4(+) + N --> CH2CNH+, thus demonstrating the viability of this important reaction in astrochemistry. The T dependence of the CH2CN/CH3CN ratio would then reflect the increasing rate of the C2H4(+) + N reaction with decreasing temperature.     

Processing of refractory meteorite inclusions (CAIs) in parent-body atmospheres

The refractory meteorite inclusions known as CAIs (calcium-aluminum rich inclusions) display melted rims that were produced by thermal events of only a few seconds duration. We show that gas dynamic deceleration in a temporary atmosphere around an accreting parent body, produced by gas release during accretion, could provide a regime of sufficiently high gas density and small scale height to achieve partial melting of the CAIs. In addition, the presence of dust in the atmosphere would increase the gradient of pressure with height (i.e., effectively reduce the scale height), lower the rate of blowoff (thus keeping more gas around the body), as well as allow dust particles to become trapped in the partially melted material as is observed in some cases. Thus, CAIs may be regarded as probes of a primitive atmosphere by virtue of the thermal and mineralogical alteration that occurred upon their passage through the atmosphere.     

利用基于GIS参数的评级方法对意大利Cilento海岸带滑坡灾害进行填图

本文论述了利用直接推断法在Agropoli和Sapri（意大利）之间的Cilento地区的海岸斜坡和陡崖进行滑坡灾害填图。这段海岸沿线（大约118公里长）主要由中生代碳酸盐岩和中新世厚砂页岩夹层构成;也有第四纪海相砂岩连同海滩砂露头。由于海浪的破坏,导致几个滑坡（主要是岩崩和滑坡）都影响海岸带。分析了大约154个斜坡和陡崖的地貌、地质及结构特征,并且监测和测量了影响岩块的若干参数。这些参数涉及研究区地形、地质、地质力学、环境和波动特征。为了实施直接推断法,采用了Hudson提出的岩石工程系统（RES）以及几种修正的方法。本研究的主要步骤是：（1）选择与滑坡灾害相关的参数;（2）分析参数之间二元耦合;（3）加权耦合的权重;（4）评价赋给不同等级的参数值：（5）最后,计算不稳定指数（I．I．）。提供了测定参数数据库。利用耦合矩阵,将输出结果链接到地理信息系统中。本研究包含以下几个要素：地质和地貌要素、有关滑坡的历史数据及研究斜坡和陡崖的I．I．的图像和数值。如果新的塌方发生或被近岸工程建筑建成,则I．I．值将被自动升级。I．I．值分为低、中、和高三个等级滑坡灾害。碳酸盐岩和厚砂页岩夹层两者都可以用相关I．I值区分,说明滑坡脆弱性的差异。事实上,除了大型崩塌外,高速且小的岩崩比中等速度的可能会造成更多的人员伤亡。大的滑坡灾害影响大约41％的碳酸盐陡崖和53％的砂质-泥炭厚砂页岩夹层边坡。     

二氧化碳的海洋封存

引言 海洋封存二氧化碳,是控制化石燃料燃烧导致气候变化的有效手段。本报告阐明了二氧化碳海洋封存的基本原理,简要叙述了有关二氧化碳海洋封存的科学领域,以及论述了二氧化碳海洋封存的环境影响。本报告也描述了在利用海洋封存限制大气二氧化碳浓度上升前需要进一步开展的研究。     

Sequential extraction of heavy metals during composting of urban waste

In urban waste （the first matter of compost）, elements such as copper, nickel and lead may be found in metallic state （wire, pile, accumulator, etc.）, which is considered as non-dependent state. The work undertaken at the laboratory of composting of the INRST in Henchir Lihoudia （Tunis） showed that the produced compost does not contain any mobile metallic element and the portion related to organic fraction （bioavailable） is tiny in size. We supposed that many reactions involving decomposition and complexation from elements related to the matrix components occurred during composting. The existence and importance of this phenomenon can be evaluated by studying the evolution of metal contents in the different fractions extracted sequentially during composting process.