文山杨柳井铝土矿矿床成因及找矿标志

铝土矿产于第四系残坡积层中,属堆积型,分布于大塘组及威宁组形成的溶蚀漏斗及洼地中。讨论矿床成因及找矿标志。     

全球季风区的定义与变化及其影响因素

从全球尺度对季风进行研究,以标准化风场季节变率(δ)和季风降水指数(MPI)这2种主要的全球季风定义方法为基础,计算出1964—2013年全球季风区平均分布,讨论了这2种结果的差异,并根据2种定义计算了全球季风指数和季风区面积时间序列,分析季风强度和季风面积的变化及相互关系。同时利用Ni■o-3.4 SST(Sea Surface Temperature)指数、南方涛动指数、太阳黑子指数以及海冰数据,使用相关分析、场分析等方法,初步探讨全球季风变化的影响因素。结果表明:(1)标准化风场季节变率定义下的季风区包含了全球大部分的季风区,主要有热带季风区、副热带季风区和温寒带季风区。季风降水定义的季风区基本覆盖了典型季风区,主要分布在热带和副热带地区;(2)在全球尺度上,季风强度和季风面积具有显著年际变化特征,且在1978—2013年间,全球季风强度呈减弱趋势,全球季风面积趋势则相反;(3)全球季风强度变化与Ni■o-3.4 SST指数和太阳黑子指数以及喀拉海、巴伦支海海域的海冰密集程度存在正向变化关系,与格陵兰海、楚科奇海海域的海冰密集程度呈负向变化关系。     

Mooring system reliability in tropical cyclone and North Sea winter storm environments

The characteristics of waves, winds and currents in a tropical cyclone environment differ significantly from those in a winter storm environment, like the North Sea. This can have a significant effect on the reliability of a mooring system that is designed to satisfy 100 yr conditions with specified Factors of Safety in accordance with ISO19901-7 or API RP 2SK. This paper presents reliability analysis of the mooring system of a permanently connected Floating LNG vessel, placed at two locations: (a) a tropical cyclone environment of the North West Shelf of Australia and (b) a winter storm environment of the North Sea. It is demonstrated that as a result of differences in the long term distribution of environmental parameters (waves, winds) between a North Sea environment and a tropical cyclone environment, the long term distribution of the mooring line response differs significantly in these two locations.This paper shows that a mooring system which is designed in accordance with ISO (or API), in these two environments, will achieve very different reliability levels because of the significant differences in environmental characteristics. In order to achieve the same reliability for the mooring system at these two geographical locations, Factors of Safety for use with 100 yr environmental conditions (Ultimate Limit State) were derived to achieve the same target probability of failure of 10⁻⁴/annum. It was found that for the North Sea environment, a factor of 1.5 is required for both the mooring chain and the pile, while for the tropical cyclone environment the required Factor of Safety has to be increased to 2.1. These differences are very significant and design standards need to be revised to reflect these findings.     

基于AdaBoost算法的多层砖房震害影响因素评估

多层砖房是最常用的结构形式之一,对其进行震害预测尤为重要,选择合适的影响因素是震害预测中最重要的环节之一。本文基于AdaBoost算法对多层砖房震害影响因素进行评估,给出影响因素重要度排序,并将结果与灰色关联分析法进行比较。研究发现结构合理性、地震峰值加速度、砖墙面积率和场地条件对多层砖房震害影响最大,因此在多层砖房震害预测中应优先考虑这4个因素,并在结构设计建造过程中予以足够重视。     

Pharmaceuticals and personal care products transference-transformation in aquifer system

Pharmaceuticals and personal care products (PPCPs) are a new kind of contaminant widely existing in the surface water and groundwater environment. In recent years, PPCPs have been received widely attention from many researchers. The migration and transformation of PPCPs are mainly photolysis, biodegradation, adsorption and hydrolysis in aquifer environment. The influencing factors of PPCPs migration include PPCPs' own physical and chemical properties, types and contents of organic matter, pH, lithology, geotechnical structure and the thickness of vadose zone, etc. At present, the research of PPCPs in China is still in the primary stage, especially on the contaminant in aquifer system. Therefore, the research in this field needs to be further strengthened.     

菏泽市岩溶地热井尾水回灌影响因素及流体可采量估算研究

通过在山东菏泽城区实施地下水回灌实验,对菏泽深覆型岩溶地区地热水的回灌影响因素进行分析研究,并初步估算出评价区可采量。结果可知:深覆型岩溶地热井尾水回灌效果的影响因素主要包括回灌压力、回灌水质、回灌水温、回灌工艺和热储层岩性特征等。在回灌条件下,估算可知允许开采量为6 408. 7 m^3/d,而本次单井地热井的抽水实验开采量值81. 48 m^3/r,远低于该值,说明菏泽城区地热资源丰富。研究结果为下一步的寒武-奥陶系岩溶热储开发打下基础。     

芙蓉李宁冈产地与原产地气象条件对比分析

对比分析原产地与引种地的气象条件,探索影响芙蓉李产量的主要气象因子,提出生产建议。     

黄河北干流晋陕蒙接壤地区环境冲突分析研究

黄河北干流晋陕蒙接壤地区在全国能源工业发展和能源基地建设布局中具有特殊重要的战略地位。但是, 由于富足的能矿资源与干旱、风沙、严重的水土流失等脆弱生态环境并存, 且呈异向关系, 历来生态问题比较突出, 近年来, 随着区内煤炭资源的大量开发和能源基地建设的快速发展,产生了一系列新的环境冲突,成为区域可持续发展的重要障碍。本文对研究区的环境脆弱形势和环境冲突因素进行了初步分析,指出了缓解环境冲突, 促进区域可持续发展的途径。     

近36年遵义市暴雨洪涝灾害变化特征及成因分析

暴雨、大暴雨等自然因素和防洪、除涝工程等社会因数是影响暴雨洪涝灾害发生、发展的重要因素。基于1984-2019年遵义市13个国家气象观测站逐日降水量资料、遵义市第一次自然灾害风险普查暴雨洪涝灾害数据,采用常规统计、突变检验、线性倾向估计、相关分析、对比分析等方法,得出遵义市暴雨、大暴雨以及受灾面积的年际、年代际以及长期变化变化特征,同时揭示农作物受灾面积的变化成因。结果表明：近36年遵义市暴雨日数及其累计降水量呈波动式微弱增加趋势,大暴雨日数及其累计降水量呈显著减少趋势,暴雨、大暴雨均具有不同的阶段性变化特征。1984-1999年农作物受灾面积呈显著上升趋势,2000-2019年农作物受灾面积呈显著下降趋势。大暴雨日数及其累计降水量与受灾面积呈显著正相关,并且具有明显的阶段性差异。暴雨洪涝灾害发生、发展既受暴雨、大暴雨等气象自然因子影响,也受气象灾害防御工程和灾害性天气预报预警水平等社会因素影响。     

浅析廊坊市浅层地下水位动态变化特征及其影响因素

通过对廊坊市近20年来浅层地下水水位观测资料进行整理分析,揭示了其水位动态曲线特征及其变化规律,找出了影响浅层地下水水位动态变化的主要因素,并就合理开发、科学利用浅层地下水资源提出了切实可行的对策措施。