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101.
102.
COD分光光度法与标准方法对比实验 总被引:3,自引:0,他引:3
CODcr分光光度快速测定法具有简便,快速,节能,省试剂等优点。其测定结果与标准方法之间有良好的可比性,最低检测限为5.0mg/l 。 相似文献
103.
Pik AJ Dangerfield JM Bramble RA Angus C Nipperess DA 《Environmental monitoring and assessment》2002,75(2):179-199
Recent conceptual and technological solutions to biodiversityassessment allow large numbers of invertebrate specimens to beprocessed rapidly and provide researchers and practitioners with a unique tool for characterizing habitats. One applicationof these advances is the ability to detect and monitor small-scale habitat heterogeneity and so provide a measure of ecosystem restoration. This case study presents a test of theefficacy of using invertebrates to assess and monitor ecologicalrestoration following bush regeneration. Eight contiguous habitatpatches within a suburb of northern Sydney, Australia, were selected to represent areas that had undergone different bushregeneration techniques. A nearby and relatively undisturbed area of bushland was also sampled. A total of 57 806 ground-active invertebrate specimens from 35 different orders were collected in pitfall traps. 1 246 ant (Formicidae) specimens were further sorted into 46 ant morphospecies from20 genera. Analyses of the three taxonomic data sets, includingtwo different data transformations, demonstrated that: (i) invertebrate communities successfully characterized different sites, providing a high degree of differentiation among sites;(ii) ordinations of the sites allowed visual assessment of theimpact of each management technique on the habitat relativeto undisturbed habitats; and (iii) characterization of sitescould be achieved using abundance classes or binary countsof ant morphospecies, representing potential cost and timesavings. The project duration was a total of three personweeks and cost less than US$3,000 (1999 prices) to complete.Measurement of invertebrate assemblages will provide a toolfor both rapid assessment of management decisions and ameans by which to implement adaptive management and restoration. 相似文献
104.
105.
MapInfo是目前流行的地理信息系统 (GIS)应用软件之一 ,由于其强大的地图功能 ,在地震监测预报中得到了越来越广泛的应用。安徽省地震局合肥遥测台网不久前完成了台网自己的速报软件的开发研制工作 ,其中运用了MapInfo部分图形操作功能。本文介绍MapInfo技术在台肥遥测台网地震速报中的一些具体应用 相似文献
106.
目的 对贮存周期内包含多个温度环境剖面的固体火箭发动机橡胶密封圈贮存寿命进行评估。方法 通过开展硅橡胶材料加速老化试验,结合Arrhenius老化规律,建立硅橡胶老化模型,获得硅橡胶加速老化等当规律,并根据等当关系开展模拟密封装置加速老化试验,考核老化后硅橡胶密封性。最后通过对固体火箭发动机贮存环境剖面进行梳理,计算出贮存周期下的等效温度,并结合试验获得的硅橡胶密封圈老化性能,直接对该贮存周期下密封圈老化寿命进行评估。结果 通过硅橡胶材料老化试验及模拟密封装置老化试验,得到了25℃下硅橡胶能够满足20 a的使用寿命。随后通过梳理并计算得出固体火箭发动机贮存周期下的等效温度为22.78℃,可以直接获得该发动机使用的硅橡胶密封圈寿命在该贮存环境下能够满足20 a使用寿命。结论 通过计算贮存周期下多个温度环境剖面的等效温度,并结合加速老化试验结论,可快速获得橡胶密封圈老化寿命。 相似文献
107.
腈氯纶吸附纤维对亚甲基蓝和铅离子的共吸附行为研究 总被引:4,自引:0,他引:4
采用无机活性炭与丙烯腈-偏氯乙烯共聚体共混,以二甲基甲酰胺为溶剂纺制了腈氯纶吸附纤维,并用水合肼控制预交联过程,通过碱性水解制得羧酸钠型离子交换吸附纤维,着重考察了该纤维在染料亚甲基蓝和重金属Pb2 混合共存条件下对2种物质的共吸附行为.结果表明,混合条件下,该纤维对亚甲基蓝和Pb2 的吸附量可分别达到9.5 mg·g-1和487.8 mg·g-1;活性炭对亚甲基蓝的物理吸附与改性纤维对Pb2 的离子交换过程同时发生,离子交换的发生对物理吸附的影响较大;Langmuir模式比Freundlich模式更适于描述Pb2 的等温吸附过程;随着温度的升高,纤维的物理吸附能力增强,而对Pb2 的离子交换性能变化不大;pH为中性条件时,纤维对Pb2 和亚甲基蓝的吸附量均达到最大. 相似文献
108.
Use of Maryland Biological Stream Survey Data to Determine Effects of Agricultural Riparian Buffers on Measures of Biological Stream Health 总被引:1,自引:0,他引:1
This study was undertaken to determine the importance of riparian buffers to stream ecology in agricultural areas. The original
Maryland Biological Stream Survey (MBSS) data set was partitioned to represent agricultural sites in Maryland's Coastal Plain
and Piedmont regions. ANOVA, multiple linear regression (MLR), and CART regression tree models were developed using riparian
and site catchment landscape characteristics. MBSS data were both stratified by physiographic region and analyzed as a combined
data set. All models indicated that land management at the site was not the controlling factor for fish IBIs (FIBI) at that
site and, hence, using FIBI to evaluate site-scale factors would not be a prudent procedure. Measures of instream habitat
and location in the stream network were the dominant explanatory factors for FIBI models. Both CART and MLR models indicated
that forest buffers were influential on benthic IBIs (BIBI). Explanatory variables reflected instream conditions, adjacent
landscape influence, and chemistry in the Coastal Plains sites, all of which are relatively site specific. However, for Piedmont
sites, hydrologic factors were important, in addition to adjacent landscape influence, and chemistry. Both Coastal Plain and
Piedmont CART models identified several hydrologic factors, emphasizing the dominant control of hydrology on the physical
habitat index (PHI). Riparian buffers were a secondary influence on PHI in the Coastal Plain, but not in the Piedmont. Between
40% and 70% of the variation in FIBI, BIBI, and PHI was explained by the “easily obtainable” variables available from the
MBSS data set. While these are empirical results specific to Maryland, the general findings are of use to other locations
where the establishment of forest buffers is considered as an aquatic ecosystem restoration measure. 相似文献
109.
快速渗滤土地处理法去除污水中挥发卤代烃的效率研究 总被引:2,自引:0,他引:2
本文就不同周期和布水率对快速渗滤系统中挥发性有机物去除率的影响进行了探讨。通过该法与六种常用的污水处理技术对挥发性卤代烃去除率的比较,表明快速渗滤土地处理法更为行之有效。 相似文献
110.
泥沙灾害和泥沙环境快速评估方法研究 总被引:4,自引:3,他引:1
泥沙灾害可以看作是泥沙环境突变或渐变积累到一定条件下发生变异时的表现形式,各类泥沙灾害和泥沙环境都具有不同的内涵和表现方面, 因此泥沙灾害和泥沙环境的评估应具有不同的对象。一旦研究的对象被确定,泥沙灾害的表现因子组合便可明确。类似地泥沙环境的环境变量和总体状况的指示怀变量也可确定。为了便于了解泥沙灾害和泥沙环境的关系,并提高评估效率,可将泥沙灾害和泥沙环境快速评估的参照组建立在能够包括影响二者表现特征的诸环境变量的最小图斑上,通过选取适当参照点,分类确定不同参照组,利用待评估地点孕灾环境因子(或环境变量)与不同参照组的相似分析。预测评估点的泥沙灾害和泥沙环境表现因子特征和动态过程. 相似文献