包头市昆都仑水库增雨燃烧炉首次作业的效果分析

通过2009年5月27日包头市昆都仑水库地面增雨燃烧炉作业实况和多普勒天气雷达速度、713天气雷达回波及区域地面自动雨量站资料的对比分析,发现在深厚的层状云系中,适时进行地面燃烧炉增雨作业,可增强区域降水量,提高增雨作业能力。分析结果为指导包头地区地面燃烧炉布点和增雨作业提供了科学依据。     

航空矢量重力测量水平分量的带限直接地形影响

基于第二类Helmert凝聚法的级数展开式,独立推导了航空矢量重力测量水平分量带限直接地形影响的计算公式。在中国西部山区选取了两条沿纬圈方向4000m航线高度上的航线,采用 的数字高程模型基于解析核计算了水平分量的直接地形影响,经低通滤波后与基于带限公式计算的地形影响进行了比较。数值计算结果表明,二者吻合较好,本文给出的带限地形影响公式可用于航空矢量重力测量水平分量的地形归算。     

水对土质边坡的稳定性影响分析

首先论述了地下水对边坡稳定性的影响因素,水对土质边坡的影响作用,接着推导出了考虑水作用影响的边坡安全系数计算公式,最后指出应用动态的观点来研究边坡体内的地下水作用.     

绿藻水溶性多糖的研究概况和进展

对近年来绿藻多糖的提纯方法、组成结构及应用的研究进展进行了综述。绿藻多糖的提纯需要经过样品的前处理、提取和精制三个步骤,提取方法包括酸提、酶提、加入钙螯合剂提取、微波及超声波辅助提取。绿藻多糖是水溶性的硫酸化杂多糖。从石莼(Ulva)、浒苔(Enteromorpha)、礁膜(Monostroma)、小球藻(Chlorella)、蕨菜(Bracken)及刚毛藻(Bristles)中提取的多糖的化学组成及结构特征各不相同,而且多糖的化学组成和结构特征受提取方式的影响。绿藻多糖的生物相容性、生物可降解性及抗氧化、抗肿瘤、抗凝血、抗炎、免疫调节等多种生物活性使其在食品、医药、化妆品及农业中具有广泛的应用。有关绿藻多糖的精确结构、提纯方法及化学修饰的进一步研究将使绿藻多糖的应用更加广泛。     

英峰岭剖面红土的粘土矿物和化学特征与成土环境关系

地球化学与粘土矿物学研究表明,广东雷州半岛英峰岭多期红土是拉弱武岩红土化初级阶段的产物,由剖面底层至顶层,红土成熟度依次递增。各层红土中主要粘土矿物含量和粘土的Ｆｅ２Ｏ３含量,以及工土和粘土的氧化,淋溶,富铁铝等化学特征系数与红土埋深之间呈波动起伏的关系。     

辽宁省积雪对自动气象站观测地气温差的影响

利用1971—2016年辽宁省61个气象站气温、地表温度、积雪日数和积雪深度资料,分析了积雪的保温作用及其对地气温差的影响。结果表明：更换自动站前后地表温度观测方式的差异导致地气温差显著增大,地气温差的增大程度受所在区域积雪日数、积雪深度的影响显著。在积雪期较长、积雪较厚的地区,积雪引起反照率增大,使得雪面温度降低,导致雪气温差减小,而雪的保温作用使得地气温差显著增大。因此,更换自动站前地（雪）气温差与积雪日数呈显著负相关,而更换自动站后地气温差与积雪日数呈显著正相关。各台站之间地气温差随积雪深度的变化系数差异较大,为0.045~0.858 ℃?cm^-1,在年平均积雪日数＜40 d、年平均极端积雪深度＜10 cm的区域,积雪的保温作用随积雪深度增大而显著增大;在年平均积雪日数＞40 d、年平均极端积雪深度＞10 cm的区域,10 cm以下的积雪对土壤保温作用随积雪深度增大显著,当积雪深度＞10 cm后,其保温作用随积雪深度增大的幅度明显减小。     

Under‐ice salinity and stable isotope distribution of Saroma‐ko Lagoon,Hokkaido, northern Japan

In winter, lakes and lagoons at high altitudes or high latitudes have interesting hydrological cycles that differ from those in other seasons or in other regions, because water surfaces are covered with ice. Hydrological balances of lakes and lagoons are complex dynamic systems, and to elucidate them, isotopic tracers of water have been used as effective tools along with observations of precipitation, evaporation, inflows, and outflows. Here, to understand hydrological processes during freezing periods in the brackish Saroma‐ko Lagoon, Hokkaido, northern Japan, we examined horizontal and vertical distributions of salinity and isotope compositions of lagoon water and ice in 2005 and 2006. Horizontal and vertical gradients of salinity and isotope compositions were observed from the river mouth to the sea channel, and factors determining these distributions were considered. The mixing of freshwater and seawater and a freezing effect were presumed to be factors in relationships between salinity and isotopes and in relationships between surface waters and ice just above the water. A simple box model for water balance was constructed based on these putative factors to reproduce the distributions of salinity and isotope compositions of surface waters and ice. An evaluation of the model revealed that this hydrological system is controlled primarily by horizontal advection of the epilimnion, freshwater influx, and the ice growth rate. Copyright © 2009 John Wiley & Sons, Ltd.     

双频道频谱激电非线性效应研究

利用双频道激发极化法，在封闭条件下和三维大水槽中，对４０余块各种天然矿物标本进行了频谱激电非线性效应研究．实验结果和理论分析表明，当电流密度增加到一定程度时，将出现激电非线性现象．用双频道频谱激电方法，将得到锯齿状频谱曲线．不同类型的矿物，锯齿状频谱曲线具有不同的特征，为评价激电异常源性质提供了新方法．     

Effect of wave nonlinearity on fatigue damage and extreme responses of a semi-submersible floating wind turbine

Floating wind turbine has been the highlight in offshore wind industry lately. There has been great effort on developing highly sophisticated numerical model to better understand its hydrodynamic behaviour. A engineering-practical method to study the nonlinear wave effects on floating wind turbine has been recently developed. Based on the method established, the focus of this paper is to quantify the wave nonlinearity effect due to nonlinear wave kinematics by comparing the structural responses of floating wind turbine when exposed to irregular linear Airy wave and fully nonlinear wave. Critical responses and fatigue damage are studied in operational conditions and short-term extreme values are predicted in extreme conditions respectively. In the operational condition, wind effects are dominating the mean value and standard deviation of most responses except floater heave motion. The fatigue damage at the tower base is dominated by wind effects. The fatigue damage for the mooring line is more influenced by wind effects for conditions with small wave and wave effects for conditions with large wave. The wave nonlinearity effect becomes significant for surge and mooring line tension for large waves while floater heave, pitch motion, tower base bending moment and pontoon axial force are less sensitive to the nonlinear wave effect. In the extreme condition, linear wave theory underestimates wave elevation, floater surge motion and mooring line tension compared with fully nonlinear wave theory while quite close results are predicted for other responses.     

中国西北内陆盆地水分垂直循环及其生态学意义

中国西北内陆盆地中的地下水系统,对维系其浅表水分、热量、盐分均衡以及地表的生态平衡、土壤的资源属性和局部地域气候相对稳定性具有不可或缺的调节作用,这种调节作用是通过饱和带水、包气带水(土壤水)、近地表大汽水和植物体内水("四水")之间的垂直循环来实现的.目前的相关研究主要侧重于地下水与地表植被类型间对应关系的统计分析,较少涉及水分运移的机制;而以水分垂直循环的动力学机制为研究对象的SPAC系统(土壤-植物-大气连续体),则对地下水的重视程度不够,且存在着尺度转换的困难,更为完整的应该是GSPAC系统(地下水-土壤-植物-大气连续体).干旱区内陆盆地地下水生态效应的研究需要开展以下的工作:"四水"垂直循环的动力学过程与机制研究,尤其是饱水带-包气带界面水、汽、热转化过程的研究;人类活动影响下地下水系统演化特征的研究,它不仅是实现水分垂直循环研究的最终目的——水资源合理开发利用的中间环节,更是将"四水"垂直循环这一微观水文循环过程与区域水文循环过程相结合,实现尺度转化的关键所在.