H~+,Li~+,Mg~(2+)∥Cl~-—H_2O四元水盐体系在-10℃时的平衡溶解度相图

本文利用等温溶解度法测定了H~+,Li~+,Mg~(2+)//Cl~-—H_2O四元水盐体系在—10℃±0.1℃时的溶解度并绘制了等温相图。相图由HCl·MgCl_2·7H_2O、MgCl_2·8H_2O、HCl·6H_2O和LiCl·2H_2O四个相区构成,只有一个零变量点I:LiCl·2H_2O+MgCl_2·6H_2O+HCl·MgCl_2·7H_2O+L_(?)利用坐标变换和直线外推法,对溶解度数据进行处理后,用湿渣结线法解决了低温平衡固相较难确定的问题。     

Focal Mechanism Solutions and Stress Field Inversion of Moderately Strong Earthquakes in the Northern Tianshan Area

Using the focal mechanism solutions of 24 moderately strong earthquakes in the northern Tianshan area, we carried out system cluster and stress field inversion analysis. The result indicates that, the focal mechanism solutions of moderately strong earthquakes are mainly dipslip reverse faulting in the northern Tianshan area. The principal rupture planes of earthquakes are NW-oriented. It is basically consistent with the strike of earthquake structure in its adjacent area. The direction of the principal compression stress P axis is nearly NS, and its inclination angle is small; while the inclination angle of the principal extensional stress T axis is large. It shows that the regional stress field is mainly controlled by the near-NS horizontal compressive stress. The direction of the maximum principal stress shows a gradation process of NNE-NS-NW from east to west.     

Effect of a thermokarst lake on soil physical properties and infiltration processes in the permafrost region of the Qinghai-Tibet Plateau,China

Changes in the hydrological processes in alpine soil constitute one of the several key problems encountered with studying watershed hydrology and ecosystem stability against the background of global warming. A typically developing thermokarst lake was chosen as a subject for a study using model simulation based on observations of soil physical properties, infiltration processes, and soil moisture. The results showed that the selected thermokarst lake imposed certain changes on the soil infiltration processes and, with the degree of impact intensifying, the initial infiltration rate decreased. The greatest reduction was achieved in the area of moderate impact. However, the stable infiltration rate and cumulative infiltration gradually increased in the surface layer at a depth of 10 and 20 cm, both decreasing initially and then increasing, which is correlated significantly with soil textures. Moreover, the cumulative infiltration changed in line with steady infiltration rate. Based on a comparative analysis, the Horton model helps better understand the effect on the soil infiltration processes of the cold alpine meadow close to the chosen thermokarst lake. In conclusion, the formation of the thermokarst lake reduced the water holding capacity of the alpine meadow soil and caused the hydraulic conductivity to increase, resulting in the reduction of runoff capacity in the area of the thermokarst lake.     

Salinivibrio sp.YH4胞外丝氨酸蛋白酶EYHS耐盐性及生物信息学分析

摘要：目的 探讨菌株Salinivibrio sp.YH4分泌的丝氨酸蛋白酶EYHS的耐盐性及结构特征。方法 明胶底物酶谱法分析EYHS的耐盐性。应用生物信息学手段对EYHS及6种耐盐的S8家族丝氨酸蛋白酶结构特征进行分析。结果 EYHS在4 mol/L的NaCl溶液中仍具有活性,属于耐盐蛋白酶。EYHS及6种S8家族丝氨酸蛋白酶分子表面的loop区等无规则卷曲所占比例较高,α-螺旋与β-片层则主要位于酶分子内部。EYHS分子表面酸性氨基酸含量较高,且具有弱疏水内核。多序列比对发现蛋白酶的催化三联体两侧存在高度保守的基序和保守的极性氨基酸及芳香族氨基酸,并存在多个保守的Gly与Ala。同源模建和表面电荷分布显示,α螺旋和β片层围成了蛋白酶的催化腔,EYHS活性中心包含由Asp32、His65与Ser215组成的催化三联体,且催化位点区域表面静电势为负。结论 上述结构特征可能有助于耐盐丝氨酸蛋白酶EYHS在高盐环境下维持其稳定性和适度柔性,并有助于其催化功能的发挥,为深入研究耐盐丝氨酸蛋白酶的高盐环境适应性提供了一定的理论依据。     

山东沂沭河流域2000BC前后古文化兴衰的环境考古

Neolithic culture series in the Yishu River Basin developed in the order of Beixin culture-Dawenkou culture-Longshan culture-Yueshi culture. During the early and middle stage of Longshan culture （4600-4300 cal. yr BP）, the climate in the Yishu River Basin was warm and wet. Paddy-oriented agriculture planted paddy was very developed. The society was flourishing with great amount of archaeological sites. The cooling starting in 4200 cal. yr BP made the paddies shortfall in output or even no seeds were gathered. This situation intensified the discrepancy between population and resource. The scarcity in natural resource led to substantial decrease in population and subsequent drop in archaeological sites. About 4000 cal. yr BP Longshan culture was displaced by Yueshi culture which was relatively un- derdeveloped, simple and unsophisticated.     

中国煤炭资源供应格局演变及流动路径分析

利用1949—2008年的相关统计数据,分析中国煤炭资源供应格局和流动路径,结果表明:(1)国家政策变动对中国煤炭资源消费规模影响深刻,每一次政策变化都会造成能源消费规模的波动,近年来强烈的能源需求使得我国煤炭供应不得不面临进口的现实;(2)受能源需求和资源禀赋的双重压力,大规模、跨区域、长距离的煤炭运输成为我国能源运输体系的重要特征;(3)尽管煤炭运输方式在向铁路、水路和公路组合并用的多元化发展,但仍然不能满足旺盛的能源需求,煤炭运输瓶颈始终存在,变输煤为输电是缓解当前煤炭运输困难的一个途径。     

青藏高原1985年冬季异常少雪和1986年异常多雪的环流及气候特征对比研究

利用青藏高原冬季异常积雪资料对比分析了 1 985年冬季异常少雪和 1 986年冬季异常多雪时期大气环流及热带海洋特征。分析结果表明 ,高原冬季多雪与少雪时中高纬度大气环流显著不同。与此同时 ,低纬热带环流及海洋特征也有明显的差异。探讨了造成这种差异的可能原因。     

长乐—南澳断裂带东山段剪切变形与剪切加热作用

本文在系统的有限应变测量的基础上,对闽东南长乐—南澳断裂带东山段剪切变形特征进行了分析:利用变形石英显微亚结构。(动态重结晶颗粒)估算了剪切带内古应力并(σ—σ_3):通过对剪切变形能密度分布W(x)格离散化计算,采用有限差分数值近方法,获得了剪切热数值解:最后总结了研究地区剪切变形,剪切加热与动热成岩成矿作用的相对时空关系以及长乐—南澳断裂域构造意义     

青岛城区一次冰雹过程分析

利用常规探测和区域自动站、雷达等资料,分析了2007年5月28日发生在青岛市的冰雹天气过程,结果表明:这次冰雹天气是在高中低3层都有冷涡系统且呈前倾槽结构的天气背景下发生的;925 hPa的西南急流和中高层的不稳定都有利于冰雹云的形成;冰雹发生前,青岛城区上空低层大气逆温、逆湿,中层有干冷空气入侵,为冰雹云形成提供了有利的位势不稳定层结;造成5月28日青岛城区降雹的直接影响系统是超级单体雷暴,冰雹云的移动和冰雹落区与地面中γ尺度气旋相对应.