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1.
固定源硫酸雾国内外采样方法优劣分析   总被引:2,自引:2,他引:0  
固定污染源硫酸雾的国标采样方法为滤筒法,但对其采样效率研究较少。在调研国内外标准方法及相关文献的基础上,通过大量实样测定,对国标采样法进行改进:在内装滤筒的烟尘采样管后串联一个冲击式吸收瓶,此改进方法弥补了国标漏测气态硫酸雾的缺陷,采样效率达到99%以上,国标法仅为改进法的47%~68%。将国标改进法与USEPA采样法进行比对,结果表明,由于中国环境本底颗粒物浓度较高,硫酸雾易吸附于颗粒物上,致使USEPA采样效率仅为国标改进法的2?4%~12%。  相似文献
2.
挥发性有机物污染土壤样品采样方法比较   总被引:1,自引:0,他引:1  
以苯系物污染土壤样品的采集为例,比较了4种不同采样方法导致样品检测结果的差异。其中,方法1将样品装填至广口瓶内并压实密封,方法2采用非扰动采样器采集10 g样品后转移至加有10 mL甲醇保护剂的Vial瓶中密封,方法3用非扰动采样器采集10 g样品后直接将其密封于采样器内,方法4用Encore采样器采样后将其密封于采样器内。结果表明,方法2采集样品的检出率最高,其余3种方法的差异不明显,方法2采集样品的检出结果71%以上都大于其余3种方法。而且,对于挥发性较强的苯与甲苯,以方法2采集的样品91%以上都大于其余3种方法,最大及平均检出浓度高出2~3个数量级。5种不同土质样品检测结果表明,对于有机质含量较低的细砂,方法2的最高及平均检出浓度均高于其余3种方法1~3个数量级,差异随土壤有机质含量的升高而降低。可见,对于苯系物及挥发性强于苯系物的其他挥发性有机物污染土壤样品的采集,方法2效果最优,可指定为VOCs污染场地土壤样品的采样方法。  相似文献
3.
主动采样法采集博物馆空气中微量污染气体   总被引:1,自引:0,他引:1       下载免费PDF全文
根据博物馆污染气体的种类,对气体主动采样法进行了采样器种类、吸收液种类和浓度、吸收液体积的选择。验证了气体采样流量、采样时间与气体采样浓度的线性关系,确定了酸性和碱性污染气体的主动采样方法,为监测文物保存环境污染气体提供了可行方法。  相似文献
4.
博物馆室内微环境中碱性气体的被动采样方法研究   总被引:1,自引:1,他引:0       下载免费PDF全文
针对博物馆微环境中的碱性污染气体-氨气,采用自行研制的被动采样器,建立了一套适合博物馆馆藏文物保存环境中氨气含量分析的被动采样-离子色谱检测方法,应用于博物馆的实地采样分析,通过与主动法采样对照,获得了被动采样器在博物馆微环境中氨的吸收系数,从而获得采样点空气中氨气的浓度,为博物馆文物保存环境监测提供了可行方法。  相似文献
5.
Scientists strive to develop efficient sampling protocols, reducing both the number of samples and processing time required, which can be adapted for use in a broad range of ecosystems. We investigated the accuracy and usefulness of artificial substrates in monitoring the impact of rising salinity on freshwater macroinvertebrate communities. We sampled seven sites along a salinity gradient (from 0.2gL-1 to 2.6gL-1) over a 19-km stretch of the Meurthe River, in northeastern France. All other parameters remained stable in this section of the river. Artificial substrate samples, each consisting of six liters of pebbles, were removed from the river at one-month intervals and examined. Results obtained indicated the same qualitative impairments as those found in samples collected using a Surber net. The use of artificial substrates was found to be a viable alternative method for assessing biological changes in river quality due to increasing salinity disturbance when Surber sampling cannot be performed.  相似文献
6.
Two boat-based and one in-water sampling method have been used to collect submerged aquatic vegetation (SAV) as part of a long-term monitoring program in Lake Okeechobee, Florida, USA. The boat-based methods consisted of collecting SAV with a ponar dredge, used only to collect Chara, and an oyster tongs-like rake apparatus, used to collect all SAV. The in-water method involved use of a 0.5 m2 PVC quadrat frame deployed by a diver. During summer 2002, SAV biomass samples were collected using all three methods at various sites in the lake to compare between-methods sampling precision. Sites used for these comparisons were selected based on plant type, plant density and sediment type. Statistical comparisons indicated that there were significant (p ≤ 0.05) biomass differences in 8 of 15 possible pairwise comparisons between sampling method biomass means. In four of the eight comparisons, significantly higher biomass mean values were obtained using the quadrat frame. In three of the remaining four comparisons, significantly higher biomass mean values were obtained with the rake apparatus. For the fourth comparison, a significantly higher biomass mean value was obtained with the ponar dredge. Three of the four relationships between SAV biomass collected by the rake and the quadrat and the rake and the quadrat/ponar dredge were statistically significant, linear and explained between 67 and 78% of the biomass variability. There were no significant differences between regression coefficients or elevations for these relationships, therefore these regressions estimated the same population regression. The population regression coefficient was 0.95, suggesting that the quadrat and ponar over-sampled relative to the rake, but the amount of this over-sampling was very small. Since there was no consistent pattern in the sampling method which yielded the significantly different biomass values and there were no significant differences in sampling precision across a range of plant species, plant densities and two sediment types, the boat-based rake method appears to be a suitable replacement for the previously used ponar dredge and quadrat methods, when in-lake measurements are not practical.  相似文献
7.
本文重点介绍了日本对当前作业环境空气中有害物质测定的设计及测定结果的评价.阐述了单元作业场所的确定以及为了解有害物质浓度的分布状况的A测定点、评价高浓度对操作者产生危险性的B测定点和为求出粉尘相对浓度变换系数的平行测定点的布点位置和作业环境的评价方法.  相似文献
8.
本文重点介绍了日本对当前作业环境空气中有害物质测定的设计及测定结果的评价.阐述了单元作业场所的确定以及为了解有害物质浓度的分布状况的A测定点、评价高浓度对操作者产生危险性的B测定点和为求出粉尘相对浓度变换系数的平行测定点的布点位置和作业环境的评价方法.  相似文献
9.
Addressing landscape-level threats to stream fishes such as habitat and hydrological alterations requires adequate watershed-level species inventories. Where watershed-level ichthyofaunal surveys are prohibitively expensive, existing (historical) data sources may provide an option for compiling species lists. However, it is critical that managers consider potential biases or limitations of species lists compiled from existing data. Here we assess the suitability of species lists compiled from existing data sources for making watershed-level fish management and conservation decisions. For nine Great Lakes watersheds, we developed existing species lists by compiling all available federal and state agency and museum fish survey data. We then compared the size and species composition of existing species lists to current species lists compiled from intensive field surveys, conducted in 2002, of the same watersheds. Species lists compiled from commonly available existing data sources, such as state and federal agency and museum data, missed many species detected during our 2002 field surveys. In most watersheds, more than 10 species were missed (range 5–21) on existing lists. Sampling over multiple years and seasons increased the size of both current (field) and existing species lists. Existing species lists compiled from surveys conducted over multiple years and seasons included an average of 15 species not captured during the 2002 field surveys. However, such multiyear existing datasets are rare and not available for many watersheds. In addition, species lists compiled from older existing surveys (e.g., before 1984) did not accurately represent current species composition of the watersheds and our results indicate several apparent misidentifications or errors on these lists. Lastly, while most game species were detected on existing lists, migratory species and recently introduced species were commonly missed on these lists. We conclude with recommendations for using existing data for watershed-level stream fish management and conservation decisions.  相似文献
10.
针对目前地表水总磷测定中样品采集和分析过程普遍存在的技术问题,选取多泥沙河流(长江、黄河)、感潮河段(浙闽片区)、湖库(太湖流域) 3类典型水体的多个点位,以及代表一般河流(除多泥沙河流和感潮河段以外的河流)水体的点位为研究对象,探讨不同现场前处理方式和分析方法对总磷测定结果的影响。结果表明:现场前处理方式是影响总磷测定结果的主要因素,总磷浓度与浊度呈正相关。对于地表水采样,建议一般河流(沉降30 min后,浊度50 NTU)采用沉降30 min的现场前处理方式,泥沙含量大的水体(沉降30 min后,浊度≥50 NTU)采用4000 r/min离心2 min的现场前处理方式,多藻类湖库水体采用63μm筛过滤的现场前处理方式。可通过浊度色度补偿消除实验室比色干扰。  相似文献
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