Urbanization and its impact on groundwater: a remote sensing and GIS-based assessment approach

The perils of unplanned urbanization and increasing pressure of human activities on hydro-geomorphologic system often result in modification of the existing recharge mechanism, which leads to many environmental consequences. In the present research, an attempt has been made to investigate the applicability of remote sensing and geographical information system (GIS) in dealing with spatial and temporal variability of dynamic phenomena, like urbanization and its impact on groundwater. This paper covers primarily, quantitative and qualitative impacts of urban growth on the behavior of aquifer in Ajmer city (India). Urban growth of the Ajmer city in last 17 years has been estimated from the satellite images. Database related to urbanization and groundwater has been created in GIS. Groundwater recharge has been computed using a water balance approach known as Water Level Fluctuation Methodology. Recharge estimation methodology has been implemented in GIS to introduce the spatial variability of hydro-geological characteristics. Further, temporal and spatial variations in groundwater quality and quantity have been correlated with urban growth using overlay analysis in GIS. The study reveals a general decline in water table and quality with urbanization. Further, remote sensing and GIS technologies have been found useful in assessment of spatial and temporal phenomena of urbanization and its impact on groundwater system.     

Gender differences in relation to wayfinding strategies, navigational support design, and wayfinding task difficulty

This study investigated user wayfinding navigational performance in terms of two navigational support designs (guide sign and you-are-here map, i.e., YAH), wayfinding strategies (egocentric/route and allocentric/survey), task difficulty (terrestrial/2D or weightless/3D), and gender differences. Eighty participants (40 males and 40 females) were recruited for the wayfinding experiment. The experimental results and statistical analysis indicated that, in the weightless VR scene, navigation time for the terrestrial/2D task type was significantly shorter than for the weightless/3D task type. The guide sign support was significantly more effective than YAH map support. Moreover, the interactions between support style and gender difference indicated that males exhibit better wayfinding performance than females, but that appropriate support can improve navigational performance and eliminate gender differences. In addition, the Way-Finding Strategy Scale result showed that the females were more likely to adopt the egocentric strategy while males were more likely to adopt the allocentric strategy, and that their scores were negatively correlated with navigational performance. Our results can be used to evaluate the interface designs of navigational support systems taking into consideration gender differences with respect to 3D VR games, including VR diving or flying navigational systems.     

TR-01稠油乳化降粘剂研究

针对河南油田井楼区块稠油,自制TR-01乳化降粘剂,通过实验研究了其降粘性能、稳定性,确定了降粘剂TR-01最佳浓度为0.3%、最佳油水比为70∶30。实验结果表明:TR-01乳化降粘剂对井楼区块油井的普遍适用性较强,具有较好的乳化降粘作用(降粘率达到99%以上),地层水对其降粘效果影响不大。其中的纳米成分能增加对污水中悬浮物的吸附能力和絮凝能力,对油田污水处理起到积极作用。     

高职高专英语课程考试的改革与实践

目前,高职高专英语课程考试仍存在试题设计不太科学、考试内容与教学要求不一致等问题,本文结合高职高专办学目标以及教育考试的实际,提出了在高职高专教育英语考试改革过程中,应着重从改革考试评价、改革考试形式及评估方法等方面入手,使考试与教学形成良性互动,构建了新的教育考试模式。     

Aging and compressibility of municipal solid wastes

The expansion of a municipal solid waste (MSW) landfill requires the ability to predict settlement behavior of the existing landfill. The practice of using a single compressibility value when performing a settlement analysis may lead to inaccurate predictions. This paper gives consideration to changes in the mechanical compressibility of MSW as a function of the fill age of MSW as well as the embedding depth of MSW. Borehole samples representative of various fill ages were obtained from five boreholes drilled to the bottom of the Qizhishan landfill in Suzhou, China. Thirty-one borehole samples were used to perform confined compression tests. Waste composition and volume-mass properties (i.e., unit weight, void ratio, and water content) were measured on all the samples. The test results showed that the compressible components of the MSW (i.e., organics, plastics, paper, wood and textiles) decreased with an increase in the fill age. The in situ void ratio of the MSW was shown to decrease with depth into the landfill. The compression index, Cc, was observed to decrease from 1.0 to 0.3 with depth into the landfill. Settlement analyses were performed on the existing landfill, demonstrating that the variation of MSW compressibility with fill age or depth should be taken into account in the settlement prediction.     

活性艳蓝X-BR降解菌的筛选

从某印染厂废水排放出口的污泥中分离到一株活性艳蓝X-BR染料高效降解菌LPY68-14,经生理生化鉴定,该菌为埃希氏菌(Escherichia sp.).研究了影响菌株LPY68-14降解效果的因素,实验结果表明:在缺氧、质量分数为0.2%葡萄糖为外加碳源、温度37℃、接种量4 mL、pH 7的最佳条件下,质量浓度为30 mg/L的活性艳蓝X-BR经菌株LPY68-14处理24 h后的降解率可达80%;当活性艳蓝X-BR质量浓度为100～400 mg/L时,该菌处理48 h后的降解率可稳定在70%左右.     

四氯化钛精制除钒废弃物的综合利用

对四氯化钛铜丝除钒精制过程中产生的废弃物,采用酸碱联合法回收其中的铜和钒。考察了关键的碱处理及盐酸沉钒过程的影响因素。实验结果为：在碱处理溶液pH12．0—13．0,碱处理温度60℃,碱处理时间1h,沉钒溶液pH1．0～1．5,沉钒温度60℃,沉钒时间1h的条件下,铜和钒的回收率分别达到90％和75％以匕,获得的阴极铜和五氧化二钒的产品质量均达到国家标准。     

重金属吸附剂壳聚糖的改性研究进展

综述了重金属吸附剂壳聚糖改性研究的新进展,介绍了交联与接枝等改性方式对壳聚糖稳定性的影响及改性后的壳聚糖对水体中重金属离子吸附性能的改善.针对壳聚糖改性中仍然存在的一些问题,指出今后研究中值得关注的方向.     

Biofiltration treatment of odors from municipal solid waste treatment plants

An in situ compost biofilter was established for the treatment of odors from biostabilization processing of municipal solid waste. The concentrations of total volatile organic compounds (VOCs) in odors and their components were measured. Biofilter media was characterized in terms of total carbon (TC), total nitrogen (TN), total phosphorus (TP), organic matter (OM), pH value and determination of bacterial colony structure. Gas chromatography–mass spectrometry (GC–MS) analysis showed that the main components of the produced gas were benzene, toluene, ethylbenzene and xylene (BTEX) along with other alkanes, alkenes, terpenes, and sulphur compounds. The compost biofilter had remarkable removal ability for alkylated benzenes (>80%), but poor removal for terpenes (～30%). Total VOC concentrations in odors during the biostabilization process period ranged from 0.7 to 87 ppmv, and the VOC removal efficiency of the biofilter varied from 20% to 95%. After about 140 days operation, TN, TC, TP and OM in compost were kept almost stable, but the dissolved N, NH₄–N and NO₃–N experienced an increase of 44.5%, 56.2% and 76.3%, respectively. Dissolved P decreased by 27.3%. The pH value experienced an increase in the early period and finally varied from 7.38 to 8.08. Results of bacterial colony in packing material indicated that bacteria and mold colony counts increased, but yeasts and actinomyces decreased along with biofilter operation, which were respectively, 3.7, 3.4, 0.04 and 0.07 times of their initial values.