The calculation of mine water yield using the non-continuous flow theory     

Liu Peigui  Tao Yuezan  Shang Manting  Yao Mei 《Environmental Earth Sciences》2014,71(2):975-981

Large amounts of groundwater are discharged during underground mining operations. As a result, the drawdown of groundwater, known as aquifer dewatering, is common in mining areas. Because of variability in permeability between different media in mines, mine drainage occurs primarily as non-continuous flow. However, calculations of mine water yield are usually made based on the continuous flow theory, and therefore often produce erroneous results. This study predicts the water yield of a mine using the module MODFLOW and incorporating the non-continuous flow theory into the calculation. Using this method, the predicted water yield of a mine was approximately 50 % lower than that predicted using the continuous flow theory. The model also demonstrates that the rate of mine drainage varies over time; there is initially a decrease in the rate of drainage which gradually approaches a constant value. Double level flow occurs when there is non-continuous flow in continuous media, which can effectively minimize the influence of mine drainage on upper aquifers and relieve the conflict between groundwater supply and drainage in the mining area.  相似文献   

Optimization of sample preparation method of total sulphur measurement in mine tailings     

A. H. Khan  J. Q. Shang  R. Alam 《International Journal of Environmental Science and Technology》2014,11(7):1989-1998

A sample preparation method of total sulphur measurement of reactive mine tailings was optimized. The total sulphur was measured by inductively coupled plasma optical emission spectroscopy, and ultrasound technique was used for sample digestion. The optimization process was adopted by a combined approach of experimental design and response surface methodology. The digestion time, temperature and acid-oxidant combination (i.e. effect of H₂O₂ with a fixed amount of acid mixture) were investigated. A two-level and three-factor (2³) full factorial design of experiment was applied to identify the most significant factors, and a central composite design was used to optimize the digestion procedure. KZK-1, a sericite schist, was selected as the certified reference material. The optimum methodology at 95 % confidence level (P < 0.05) was identified to be 10 min of digestion at 77 °C, with a solution of 1 ml HNO₃:1 ml HCl:1.35 ml H₂O₂. This combination resulted in 100 % sulphur recovery. The investigated method was verified by X-ray diffraction analysis. The optimum digestion level was applied to a reactive mine tailings, which achieved satisfactory results with a percentage relative standard deviation < 3 %.  相似文献   

湖北冷季高架雷暴天气分类及环境参数特征分析     

苟阿宁  姚雯  雷彦森  明绍慧  鲁易  魏凡 《热带气象学报》2024,(1):23-32

利用常规观测资料、加密地面自动站、闪电定位仪和ERA5再分析资料,将2011—2020年湖北冷季91次高架雷暴事件,按照形成机制分为雷雨型、强对流型和雷打雪型3类,并细致归纳了3类事件的时空分布特征、大气环流背景及关键环境参数等特征。(1) 湖北冷季高架雷暴雷雨型最多,强对流型次之,雷打雪型最少。3类型存在明显的时空分布差异,雷雨型主要发生在秋末冬初(11月)和冬末初春(1—2月),强对流型及雷打雪型常出现在早春2月,3月基本以强对流型为主。(2) 低槽冷锋、850 hPa切变线及低空西南急流是冷季高架雷暴发生的有利环流背景,近地面为稳定的冷气团控制,逆温明显,西南低空急流沿着锋面逆温层以上的850 hPa附近触发抬升,水汽、上升运动及不稳定层结均出现在850 hPa以上。雷雨型和雷打雪型距离冷锋超过100 km以上,强对流型不足100 km。(3) 850 hPa是风场转换的重要层次。强对流型850 hPa露点温度(Td850)、K指数、850 hPa与 500 hPa温差(ΔT85)、850 hPa假相当位温(θse850)、西南急流厚度和强度(I700)、切变线强度(S850)最大,中低层(850~700 hPa)垂直风切变(SL78)最小;雷打雪型对水汽和不稳定能量的要求最低,SL78最大。  相似文献   

FAST周边2010—2020年暴雨特征分析          下载免费PDF全文

苟杨  宋彦棠  谢亚玲  顾欣 《中低纬山地气象》2022,46(4):88-91

利用2010—2020年FAST周边最近的克度、塘边、董架3个区域自动站的逐日降水量资料及暴雨日逐小时降水量资料,运用统计学方法对FAST周边暴雨发生特征、强度、月际变化、小时分布等进行分析。结果表明：2010—2020年FAST周边各站发生暴雨43~47次,大多数为对流性或混合性降水,暴雨持续时间总体较短,多数情况为1~2 h。暴雨主要发生在夏秋季,最易发生的月份是6月,最易发生的暴雨雨量是50~100 mm,暴雨在夜间至清晨（22时—06时）最易发生。各站1周内发生2次暴雨的有5~9次,1个月内发生3次暴雨的有4~6次,连续3次暴雨发生的最短时间为11~13 d。近11 a中,FAST周边各站发生大暴雨以上降水5~7次,其中最大雨量为2014年7月4日FAST东北面克度站205.1 mm。  相似文献   

The influence of turbulent mixing on the subsurface chlorophyll maximum layer in the northern South China Sea     

Shang  Chenjing  Liang  Changrong  Chen  Guiying  Gao  Yongli 《中国海洋湖沼学报》2021,39(6):2167-2180

Journal of Oceanology and Limnology - We present observations from deployments of turbulent microstructure instrument and CTD package in the northern South China Sea from April to May 2010. From...  相似文献   

新疆西部苏盖特构造带构造特征及勘探前景   总被引：4，自引：4，他引：0       下载免费PDF全文

吴超  尚新璐  陈军  王晓云 《地质科学》2004,39(4):571-579

苏盖特构造带位于新疆昆仑山弧形推覆体前缘.本文通过研究苏盖特构造带的构造特征,确定了地震反射层的地质属性,认为苏盖特构造带由表层推覆体及下部下第三系-二叠系之间的地层经过3次重复形成的叠瓦状推覆体构成.苏盖特构造带活动始于上新世阿图什组沉积期,定型于更新世.通过研究西昆仑逆冲推覆体及已钻探井的地表油源、储层特征及储盖组合,认为苏盖特构造带具有两套好的油源即石炭-二叠系及侏罗系油源,两套好的储集层即白垩系和下第三系储层,相应地,发育两套储盖组合,具有良好的圈闭及运聚条件,是有利的勘探目标区.  相似文献   

关于对龙居镇宅基用地情况的调查          下载免费PDF全文

赵云秀  商述珍 《山东国土资源》2006,22(6):56-57

农村居民点用地是非农业建设用地的重要组成部分，加强农村居民点用地管理，对稳定耕地面积，实现耕地总量动态平衡有着十分重要的意义。为了更全面地了解农村宅基用地的现状、存在的问题，寻求解决问题的途径，龙居镇国土资源所对全镇有代表性的8个村庄的农村宅基用地问题进行了调研。  相似文献   

A VERTICAL DISTRIBUTION MODEL OF NUTRIENTS AND DISSOLVED OXYGEN IN THE SOUTHERN TAIWAN STRAIT   总被引：3，自引：0，他引：3  

商少凌  洪华生 《中国海洋湖沼学报》1995,13(1):51-61

Sinoe vertical transport of nutrients and dissolved oxygen are quite important in the water col-umn and have drawn serious attention these recent years, a one-dmension numerical model is tried to simulate the vertical distribution of nutrients and dissolved oxygen in June at two research sites in the southemTaiwan Strait. Physical transport parameters are calibrated by temperature simulation, and thenare used to simulate the profiles of NO_3, PO_4 and dissolved oxygen. The simulation was generally success-ful for both stations. The importance of various factors, such as upwelling tidal current andbiogeochemical activities, which influence the vertical distribution of nutrients and dissolved oxygen, is revealed by analysis of the modeling results. Some important rates, fluxes and ratios are also estimated anddiscussed on the basis of simulation.  相似文献   

NECESSITY AND METHOD OF PUBLIC PARTICIPATION IN STRATEGIC ENVIRONMENTAL ASSESSMENT OF CHINA     

RENLi-jun SHANGJin-cheng 《中国地理科学(英文版)》2005,15(1):42-46

1INTRODUCTIONFor recent years, many countries have increasingly paidattention to the research on strategic environmental as-sessment (SEA) and taken it as one of key supportingtools for pursing sustainable development (BROWNand THERIVEL, 2000; PRARTIDARIO…  相似文献   

云南天文台大气视宁度观测和初步探讨   总被引：1，自引：1，他引：0  

钱铜铃  李玉兰  尚琼珍  李景谦  许骏  岑学奋 《天文研究与技术》1996,(Z1)

介绍了为云南丽江高美古选址点作对比的云南天文台点的大气视宁度观测统计和结果，对观测过程中的有关问题作了初步探讨。对高美古和云南天文台的１９９５年５月和１９９５年１２月２０日观测资料作了对比，结果表明：高美古选址点的视宁度明显优于云南天文台。  相似文献