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排序方式: 共有692条查询结果,搜索用时 687 毫秒
301.
二氧化铈粉尘治理及回收技术探索杜品森(云南光学仪器厂昆明650114)二氧化铈(CeO2)是光学研磨工艺中大量使用的一种抛光粉,虽然价格昂贵,但经理化深加工处理后,粒径超细达5微米以下时仍能保持符合光学玻璃抛光所需要的六方体晶格及硬度,能在频繁的镜片... 相似文献
302.
通过调研和咨询,研究了常熟市乡村生活垃圾的产量、组成、收集处理和管理模式等。调查表明,常熟市乡村人均生活垃圾日产生量为1.11 kg,主要垃圾成分的占比顺序为厨余>塑料>纸类>布类,其中厨余垃圾约占70%。常熟市乡村垃圾治理采取"组保洁、村收集、镇转运、市处理"的收运处理模式,并因地制宜采用焚烧发电的终端处理方式,在管理方面强化"统一规划、保障资金、监督管理、宣传推广"。由于技术和管理体系较为完善,常熟市乡村垃圾治理达到或接近发达国家水平。但当前常熟市乡村垃圾治理仍存在无区别对待、混合式收集、过度离域处理的问题。结合常熟市实际情况,建议从因地制宜、源头分类、原位处理等方面进行完善,并依据村落类型,提出了两种改进策略。 相似文献
303.
选用钢铁行业袋式除尘用滤料,采用泡点法进行孔径及孔径分布测试,并进行了除尘滤料冷静态过滤性能测试。通过对实验数据分析得到:针刺滤料平均孔径为22.22~26.83μm,孔径分散程度较高;覆膜针刺过滤材料平均孔径仅为1.0μm左右,孔径分布较为集中;针刺滤料的孔径会影响到其透气性,透气性随着最大孔径的增加而增加;针刺滤料孔径及孔径分布对过滤效率有直接的影响,孔径越大,孔径分布分散程度越高,过滤效率越低,过滤阻力越小;过滤风速为1.0 m/min时覆膜滤料对微细颗粒物的捕集效率达到80%左右,约为普通针刺毡滤料的2~4倍,阻力约为普通针刺毡滤料的14~32倍。 相似文献
304.
DIRK S. SCHMELLER PIERRE-YVES HENRY ROMAIN JULLIARD BERND GRUBER JEAN CLOBERT FRANK DZIOCK SZABOLCS LENGYEL PIOTR NOWICKI ESZTER DÉRI EDUARDAS BUDRYS TIIU KULL KADRI TALI BIANCA BAUCH JOSEF SETTELE CHRIS VAN SWAAY REJ KOBLER VALERIJA BABIJ EVA PAPASTERGIADOU KLAUS HENLE 《Conservation biology》2009,23(2):307-316
Abstract: Without robust and unbiased systems for monitoring, changes in natural systems will remain enigmatic for policy makers, leaving them without a clear idea of the consequences of any environmental policies they might adopt. Generally, biodiversity-monitoring activities are not integrated or evaluated across any large geographic region. The EuMon project conducted the first large-scale evaluation of monitoring practices in Europe through an on-line questionnaire and is reporting on the results of this survey. In September 2007 the EuMon project had documented 395 monitoring schemes for species, which represents a total annual cost of about €4 million, involving more than 46,000 persons devoting over 148,000 person-days/year to biodiversity-monitoring activities. Here we focused on the analysis of variations of monitoring practices across a set of taxonomic groups (birds, amphibians and reptiles, mammals, butterflies, plants, and other insects) and across 5 European countries (France, Germany, Hungary, Lithuania, and Poland). Our results suggest that the overall sampling effort of a scheme is linked with the proportion of volunteers involved in that scheme. Because precision is a function of the number of monitored sites and the number of sites is maximized by volunteer involvement, our results do not support the common belief that volunteer-based schemes are too noisy to be informative. Just the opposite, we believe volunteer-based schemes provide relatively reliable data, with state-of-the-art survey designs or data-analysis methods, and consequently can yield unbiased results. Quality of data collected by volunteers is more likely determined by survey design, analytical methodology, and communication skills within the schemes rather than by volunteer involvement per se. 相似文献
305.
J. A. Camiñas N. Cano D. Cortés V. Díaz del Río A. García J. P. Rubín 《Journal of Coastal Conservation》1998,4(1):43-50
In October 1992, the Oceanographic Centre of Málaga of the Spanish Oceanographical Institute (IEO) started a monitoring project,Ecomálaga, which collects physical, chemical, biological and sedimentological data from the Alborán Sea shelf. The project is coordinated
with similar projects in the Atlantic and Mediterranean Centres of IEO. The ultimate objective is to, understand the long-term
changes of the essential marine-environmental parameters.
So far, nine quarterly surveys have been carried out—from October 1992 to December 1994. The following variables were registered:abiotic: location weather, water temperature, salinity, pH, dissolved oxygen, chlorophyll a, nitrate, nitrite, phosphate, silicate,biotic: zooplankton biomass and species composition, and ichthyoplankton. The granulometric composition and organic matter content
of sediments are also included.
Data are stored in a computerized data base named Ecomálaga Data Base, with contributions from geology, physics, plankton
biology and marine chemistry. The data base not only contains separate files for each research topic, but also allows for
interchange between these files, resulting in a synoptic data output. It offers the users an output in the form of synthetic
records of each station sampled.
The analysis of the data indicates seasonal influences and ainshore-offshore gradient, as well as an Atlantic influence on
the stations located in the transect closest to the Strait of Gibraltar. 相似文献
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308.
粪便与厨余垃圾现场处理研究 总被引:3,自引:0,他引:3
研究了粪便与厨余垃圾的源头真空管道收集及现场生物处理技术,根据系统工艺设计方案进行了分单元的小试.研究表明:真空便器的冲水量约为1L/次,破碎1kg垃圾用水0.4~0.6L;厌氧消化反应器进料粪便占40%,厨余垃圾占60%,水分控制在93%左右,C/N=25∶1左右,pH控制在6.2~7.3之间,最佳搅拌频率为6h/d,总停留时间28d;ABR反应器对混合上清液的COD去除率可达91%;用驯化得到的解磷、解钾菌株与消化污泥混合制取菌肥,解磷菌对土壤有效磷增强度67.5%,解钾菌对土壤有效钾增强度33.4%. 相似文献
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