地下水对混凝土的pHs分解性侵蚀判别式

针对地下水对混凝土分解性侵蚀指标pHs现行评价方法中存在水样间pHs横向没有可对比性和难以定量绘制pHs分解性侵蚀分区图等两大缺陷,推出了一个新的pHs分解性侵蚀判别式sk1,用编制的"地下水对混凝土分解性侵蚀判别式计算程序",完成了新定义的判别式sk1的计算,计算结果不但具备了水样间的每种分解性侵蚀横向对比的功能,而且还具备了定量绘制每种分解性侵蚀分区图和定量绘制3种分解性侵蚀综合评价迭加图的功能。通过实例应用,形象地印证了现行评价方法存在的缺陷及现推出的判别式、定量编绘侵蚀分区图的可行性。     

钻孔多参量指标预测冲击地压危险性的试验研究

为准确预测预报冲击地压危险性,提出一种通过监测钻孔过程中钻杆推力、钻杆扭矩与钻屑量等钻孔多参量指标变化规律来预测冲击危险性的方法。利用自主研制的钻孔多参量一体化测试装置,在实验环境下对不同煤体应力状态下的多参量指标进行测试分析,发现钻杆扭矩与钻屑量均随着煤体应力的增大而增大,钻杆推力随着钻进时间的增加呈现先增大再减小,并出现波谷随后增大最后减小的规律。在相同钻机及钻具条件下,进行井下原位钻孔试验,结果表明：随着钻进深度增大,钻杆扭矩与钻屑量变化规律呈现较好一致性,在5 m深度前均先增大随后减小;钻杆推力在1~4 m内呈上升趋势,在5 m处下降至波谷位置,随后推力值再次上升,最后呈稳定趋势。对此区域应力分布带情况进行划分,可确定应力峰值点大致在孔深5 m处,并利用SPSS数据分析软件初步确定此试验点钻杆推力临界指标为7.5 kN,钻杆扭矩临界指标为50.0 N·m。研究结果可为冲击地压等煤矿动力灾害危险性的预测预报提供理论基础与工程指导。     

Global temperature and monsoon activity

In this paper an attempt has been made to search a new parameter for the prediction of the Indian summer monsoon rainfall. For this purpose the relationship of the global surface-air temperature of four standard seasons viz., Winter (December-January-February), Spring (March-April-May), Summer (June-July-August), Autumn (September-October-November) with the Indian summer monsoon rainfall has been carried out. The same analysis is also carried out with surface-air temperature anomalies within the tropical belt (30°S to 30°N) and Indian summer monsoon rainfall. For the present study data for 30 years period from 1958 to 1988 have been used. The analysis reveals that there is a strong inverse relationship between the monsoon activity and the tropical belt temperature.     

珞珈一号夜间灯光影像在建设用地提取中的应用:以武汉市为例

城市建设用地能够反映城市建设发展在地域空间上的分布形态,是规划主管部门监测城市建设和扩张的关键指标.2018-06-02发射的珞珈一号卫星可提供130 m分辨率的夜间灯光数据,在城市建设用地的提取方面具有较大潜力.首先整合珞珈一号夜间灯光影像与Landsat 8多光谱影像以及网络地图兴趣点数据;然后分别采用人类居住合成...     

Distribution of Cd,Pb, Zn and Cu and their chemical speciations in soils from a peri-smelter area in northeast China

An exploratory study on soil contamination of heavy metals was carried out surrounding Huludao zinc smelter in Liaoning province, China. The distribution of total heavy metals and their chemical speciations were investigated. The correlations between heavy metal speciations and soil pH values in corresponding sites were also analyzed. In general, Cd, Zn, Pb, Cu and As presented a significant contamination in the area near the smelter, comparied with Environmental Quality Standards for Soils in China. The geoaccumulation index showed the degree of contamination: Cd > Zn > Pb > Cu > As. There was no obvious pollution of Cr and Ni in the studied area. The speciation analysis showed that the dominant fraction of Cd and Zn was the acid soluble fraction, and the second was the residual fraction. Pb was mostly associated with the residual fraction, which constituted more than 50% of total concentration in all samples. Cu in residual fraction accounted for a high percentage (40–80%) of total concentration, and the proportion of Cu in the oxidizable fraction is higher than that of other metals. The distribution pattern of Pb and Zn was obviously affected by soil pH. It seemed that Pb and Zn content in acid solution fraction increased with increasing soil pH values, while Cd content in acid soluble fraction accounted for more proportion in neutral and alkaline groups than acidic one. The fraction distribution patterns of Cu in three pH groups were very similar and independent of soil pH values. And the residual fraction of Cu took a predominant part (50%) of the total content.     

城市地下空间开发利用地质适宜性三维评价指标体系研究——以杭州市为例

地下空间开发地质适宜性三维评价是合理进行地下空间立体化开发、降低开发地质风险的重要手段,也是当前研究热点。作为地质适宜性三维评价全过程的重要一环,科学合理地建立三维评价指标体系是其能否正确开展的前提基础。通过结合杭州城市地下空间开发面临的地质问题,在系统分析各评价指标对地下空间开发建设影响的特征基础上,以三维视角从地层三维结构等多个方面构建完成了一套具有多层次结构的三维评价指标体系,并采用层次分析方法对评价指标进行了目标权重的计算、一致性检验、排序和分析。该指标体系可划分为5个准则层21个指标层,相较于二维评价指标体系,通过融合三维地质模型和三维空间分析方法,使评价过程中能够考虑更多的评价因子,更好地描绘地下复杂的三维地质环境,丰富了三维评价结果的内涵。基于模糊综合评价方法的杭州钱江新城二期的三维评价应用成果表明,该指标体系为三维地质模型和三维空间分析方法之间的整合提供了有力的指导,为提升三维尺度下的地下空间开发地质适宜性评价精度和准确性提供了有力的支持。     

矿山地质环境评价中最佳评价尺度确定方法的研究及应用

矿山地质环境的评价对于矿产资源的开发利用、矿山环境的恢复治理有重要意义,在评价工作中最佳评价尺度的确定有助于提高评价结果的精确性和统一性。本次研究从矿山地质环境的评价内容出发,提出一种最佳评价尺度的确定方法。在不同尺度下,将评价区域按照边界划分成网格评价单元,通过定量化评价指标的尺度效应表现(异质性、一致性、信息量、破碎度),求出其随尺度变化的拟合函数,进而建立最佳评价尺度函数,并求出其评价适宜区间和最佳评价尺度。将该方法应用到福建省龙岩市新罗区、三明市大田县矿山地质环境评价中,得到新罗区和大田县的最佳评价尺度适宜区间分别为[997.8 m,1 194 m]、[955.5 m,1 297.8 m],最佳评价尺度分别为1 049.6 m、1 182.1 m。在该评价尺度区间内,所得到的评价结果基本一致,并且在最佳评价尺度下评价结果的效果更好,从而证明了该方法的可行性。研究表明,最佳评价尺度函数受到研究区范围、评价内容分布情况、自然地理情况等因素的综合影响。该研究成果可以为矿山地质环境评价工作中评价尺度的确定提供理论依据。     

中国东北地区地表干湿状况的变化及趋势分析

利用1961~2000年中国东北地区80个测站的月降水和平均气温资料,通过计算地表最大潜在蒸发、地表干燥度指数和地表水分盈亏量,分析了东北地区及其7个不同气候区域地表干湿状况的时空分布规律及其变化趋势,并探讨了它与降水和气温的关系。结果表明,东北地区及其不同区域的地表干湿状况不仅具有较大的地域差别和年际及年代际变率,而且存在着明显的阶段性和低频变化特征,特别是20世纪90年代中期以来,东北地区呈现出较强的变干倾向,并且由于气温升高所导致的潜在蒸发的加大与降水一样对这一变干倾向也有十分重要的影响。     

Geochemical modeling,fate distribution,and risk exposure of potentially toxic metals in the surface sediment of the Shyok suture zone,northern Pakistan

The objective of the current study was to assess the contamination of potentially toxic metals (PTMs) in weathered surface sediment, along stream tributaries, and surrounding area of the river Chitral, Shyok suture zone district Chitral, Pakistan. To understand the geochemical features of 113 sediment, samples were collected from the Mirkhani and Drosh area. Then, different statistical tools including the geo-accumulation index (Igeo), cluster analysis (CA), principal component analysis (PCA), and ecological risk assessment (ERA) were used to unravel the origin, intensity, and exposure level of PTMs to control risk and restore the ecosystem within the study area. The results for the PTMs namely nickle (Ni), chromium (Cr), copper (Cu), cadmium (Cd), lead (Pb), zinc (Zn), and cobalt (Co) in Mirkhani and Drosh were in the following ranges: 10–150, 15–210, 15–250, 0.08–1.00, 10–70, 76–240 and 14–51; and 13–240, 17–210, 15–150, 0.08–0.60, 7–140, 47–150 and 13–36 mg/kg, respectively. In consequence, the potential ecological risk caused by Pb, Ni, Cu, Co, Cr, and Zn is reflected by the percentages of samples with an ecological risk index (ERI) greater than one which were 100%, 91%, 100%, 100%, 92%, and 100%, respectively. However, the overall mean decreasing order of ecological risk of PTMs in the district Chitral was Pb > Ni > Cu > Co > Cr > Zn > Cd. Moreover, the PCA yielded 78% variability which indicated that mineral prospects play an important role in the contamination of sediment. Furthermore, the mineral phases of Pb and Zn suggested supersaturation, while that for Cd revealed unsaturation. The results of Igeo, ERI, and CA indicated contamination of PTMs in the study area. The ERI value of Pb, Ni, Cu, Co, Cr, and Zn was higher than 1 suggesting an ecological risk in the study area. Moreover, the current study showed the dominance of geogenic contamination with major contributions from ultramafic rock and known mineral prospects. Therefore, contaminated sediment of the Shyok suture zone is extremely detrimental to the aquatic ecosystem of the study area.     

东北地区城市民生质量测度与空间分析

民生问题是当今中国政府和民众高度关注的热点问题,也是全面建成小康社会进程中需要迫切解决的关键科学问题。借鉴当代中国人的价值观结构,构建了民生质量评估指标体系,定量测度了东北地区34个地级市的民生质量指数,并采用ESDA和多元线性回归模型探讨其空间分异特征及其影响因素。研究结果表明：① 东北地区城市民生质量呈等级分布特征,且“两极分化”明显。② 经济实力、产业结构、城市化和地理邻近性对民生质量空间分异有重要影响。