全文获取类型
收费全文 | 144篇 |
免费 | 0篇 |
国内免费 | 4篇 |
专业分类
安全科学 | 5篇 |
废物处理 | 31篇 |
环保管理 | 6篇 |
综合类 | 29篇 |
基础理论 | 21篇 |
污染及防治 | 39篇 |
评价与监测 | 6篇 |
社会与环境 | 9篇 |
灾害及防治 | 2篇 |
出版年
2023年 | 2篇 |
2022年 | 1篇 |
2021年 | 3篇 |
2020年 | 2篇 |
2019年 | 2篇 |
2018年 | 3篇 |
2017年 | 6篇 |
2016年 | 5篇 |
2015年 | 3篇 |
2014年 | 5篇 |
2013年 | 5篇 |
2012年 | 3篇 |
2011年 | 6篇 |
2010年 | 7篇 |
2009年 | 13篇 |
2008年 | 11篇 |
2007年 | 7篇 |
2006年 | 10篇 |
2005年 | 12篇 |
2004年 | 4篇 |
2003年 | 11篇 |
2002年 | 5篇 |
2001年 | 1篇 |
2000年 | 2篇 |
1999年 | 2篇 |
1998年 | 1篇 |
1997年 | 3篇 |
1994年 | 1篇 |
1991年 | 2篇 |
1990年 | 2篇 |
1989年 | 2篇 |
1988年 | 1篇 |
1987年 | 1篇 |
1982年 | 1篇 |
1981年 | 1篇 |
1976年 | 1篇 |
1956年 | 1篇 |
排序方式: 共有148条查询结果,搜索用时 31 毫秒
41.
Large-volume seawater samples were collected in the Sulu and South China Seas and their (137)Cs activities were determined by gamma-ray spectrometry using a low background type high-purity Ge detector. Vertical distributions of (137)Cs activity showed an exponential decrease in the South China Sea, whereas a subsurface maximum at 200m depth and monotonic decrease below 300m were observed in the Sulu Sea. A significant difference in intermediate water (137)Cs activities in the 500-2000m depth was observed between the Sulu and South China Seas, i.e., the (137)Cs activities in the Sulu Sea were remarkably higher than those in the South China Sea. The difference in the (137)Cs inventory below 500m was approximately 1200Bqm(-2) between the Sulu and South China Seas. The (137)Cs total inventory of 3200Bqm(-2) in the Sulu Sea was 5.7 times higher than that expected from global fallout. A possible mechanism controlling this extremely high (137)Cs total inventory may be inflows of the (137)Cs rich water masses through the Luzon Strait, lateral transport across the Mindoro Strait into the Sulu Sea, and then subduction into the deep layer in the basin. 相似文献
42.
43.
Kazunori Fujita Gouki Sasaki Kazuki Kobayashi 《Journal of Material Cycles and Waste Management》1999,1(1):48-52
We have investigated a fabric-filter-supported catalyst for removing harmful solid and gaseous compounds simultaneously from
municipal incinerator exhaust gas. We studied the ways in which the efficiency of NO
x
removal is influenced by filter temperature, gas flow rate, and catalyst content. The reduction of the catalyst content by
mechanical reverse washing was investigated, and the state of the catalyst supported in the fabric filter was also observed
using a scanning electron microscope. The catalyst supported by the fabric filter showed a removal efficiency above 75% when
the filter temperature was 200°C, the gas flow rate was 1 m/min, and the catalyst content of the fabric filter was above 300 g/m2. The catalyst was supported uniformly on the fibers of the fabric filter, and fine catalyst particles remained on the fibers
after mechanical reverse washing.
Received: October 15, 1997 / Accepted: March 19, 1999 相似文献
44.
Spatial variability of nitrous oxide emissions and their soil-related determining factors in an agricultural field 总被引:1,自引:0,他引:1
Yanai J Sawamoto T Oe T Kusa K Yamakawa K Sakamoto K Naganawa T Inubushi K Hatano R Kosaki T 《Journal of environmental quality》2003,32(6):1965-1977
To evaluate spatial variability of nitrous oxide (N2O) emissions and to elucidate their determining factors on a field-scale basis, N2O fluxes and various soil properties were evaluated in a 100- x 100-m onion (Allium cepa L.) field. Nitrous oxide fluxes were determined by a closed chamber method from the one-hundred 10- x 10-m plots. Physical (e.g., bulk density and water content), chemical (e.g., total N and pH), and biological (e.g., microbial biomass C and N) properties were determined from surface soil samples (0-0.1 m) of each plot. Geostatistical analysis was performed to examine spatial variability of both N2O fluxes and soil properties. Multivariate analysis was also conducted to elucidate relationships between soil properties and observed fluxes. Nitrous oxide fluxes were highly variable (average 331 microg N m(-2) h(-1), CV 217%) and were log-normally distributed. Log-transformed N2O fluxes had moderate spatial dependence with a range of >75 m. High N2O fluxes were observed at sites with relatively low elevation. Multivariate analysis indicated that an organic matter factor and a pH factor of the principal component analysis were the main soil-related determining factors of log-transformed N2O fluxes. By combining multivariate analysis with geostatistics, a map of predicted N2O fluxes closely matched the spatial pattern of measured fluxes. The regression equation based on the soil properties explained 56% of the spatially structured variation of the log-transformed N2O fluxes. Site-specific management to regulate organic matter content and water status of a soil could be a promising means of reducing N2O emissions from agricultural fields. 相似文献
45.
Questionnaire surveys and subjective evaluations on residential environment were performed in order to grasp the main factors of residential environment of small local cities. The suitable evaluation index system was established, and the regional residential environment characteristics and personal residential preference types were analyzed, so that their influence on residential environment evaluation could be grasped. The results can be applied to the residential environment planning, construction and monitoring of local cities. 相似文献
46.
Watanabe M Takamatsu T Koshikawa MK Sakamoto K Inubushi K 《Journal of environmental monitoring : JEM》2006,8(1):167-173
We developed a method to analyze atmospheric SO(x) (particulate SO(4)(2-)+ gaseous SO(2)) and NO(x) (NO + NO(2)) simultaneously using a battery-operated portable filter pack sampler. NO(x) determination using a filter pack method is new. SO(x) and NO(x) were collected on a Na(2)CO(3) filter and PTIO (2-phenyl-4,4,5,5-tetramethylimidazoline-3-oxide-1-oxyl) + TEA (triethanolamine) filters (6 piled sheets), respectively. Aqueous solutions were then used to extract pollutants trapped by the filters and the resulting extracts were pre-cleaned (e.g. elimination of PTIO) and analyzed for sulfate and nitrite by ion chromatography. Recoveries of SO(2) and NO(x) from standard pollutant gases and consistency of the field data with those from other instrumental methods were examined to evaluate our method. SO(x) and NO(x) could be analyzed accurately with determination limits of 0.2 ppbv and 1.0 ppbv (as daily average concentrations), respectively. The sampler can determine SO(x) and NO(x) concentrations at mountainous or remote sites without needing an electric power supply. 相似文献
47.
Akio Kamimura Eisuke Konno Shigehiro Yamamoto Takeru Watanabe Kazuo Yamada Fumiaki Tomonaga 《Journal of Material Cycles and Waste Management》2009,11(2):133-137
The synthesis of recycled plastics from recovered monomeric materials obtained from the depolymerization reaction of fiber-reinforced
plastics (FRP) was examined. The depolymerization reaction of FRP in the presence of N,N-dimethylaminopyridine (DMAP) smoothly yielded the corresponding monomers, which mainly consisted of dimethyl phthalates.
The polymerization reaction with this monomer failed to form the corresponding unsaturated polyesters due to contamination
by N-methyl-4-pyridone, a decomposition product of DMAP. An efficient purification of the recovered monomer was achieved by washing
with water, and the purified monomer successfully yielded the corresponding polymers. A hardness test revealed that the polymers
were as hard as the polyester made from virgin materials. The present modification provides a practical method for the preparation
of recycled plastics from depolymerized plastics. 相似文献
48.
Robert Gifford Leila Scannell Christine Kormos Lidia Smolova Anders Biel Stefan Boncu Victor Corral Hartmut Güntherf Kazunori Hanyu Donald Hine Florian G. Kaiser Kalevi Korpela Luisa Marie Lima Angela G. Mertig Ricardo Garcia Mira Gabriel Moser Paola Passafaro José Q. Pinheiro Sunil Saini Toshihiko Sako Elena Sautkina Yannick Savina Peter Schmuck Wesley Schultz Karin Sobeck Eva-Lotta Sundblad David Uzzell 《Journal of environmental psychology》2009
The personal assessments of the current and expected future state of the environment by 3232 community respondents in 18 nations were investigated at the local, national, and global spatial levels. These assessments were compared to a ranking of each country's environmental quality by an expert panel. Temporal pessimism (“things will get worse”) was found in the assessments at all three spatial levels. Spatial optimism bias (“things are better here than there”) was found in the assessments of current environmental conditions in 15 of 18 countries, but not in the assessments of the future. All countries except one exhibited temporal pessimism, but significant differences between them were common. Evaluations of current environmental conditions also differed by country. Citizens' assessments of current conditions, and the degree of comparative optimism, were strongly correlated with the expert panel's assessments of national environmental quality. Aside from the value of understanding global trends in environmental assessments, the results have important implications for environmental policy and risk management strategies. 相似文献
49.
cis-Chlordane, trans-chlordane, and heptachlor were photodegraded in ethanol, and their degradation fates and degradation products were determined by a computational chemical method. The most degradable material was heptachlor (first-order reaction constant k=0.13 min(-1)). Chlorine balances changed during UV irradiation, and the chlorine atoms in chlordane and heptachlor were eventually mineralized. cis-Chlordane, trans-chlordane and heptachlor each generated two di-dechlorinated products. Reactivities at various positions in these compounds were predicted on the basis of bond dissociation energies calculated by nonempirical molecular orbital calculation (Gaussian 98W). 相似文献
50.
Ionizing radiation is ubiquitous, but very few experiments have investigated the biological effects of the natural background radiation at very low doses (>10 mGy/yr). We examined whether the background radiation, or radiation of a slightly higher level, has a role in evoking changes in behaviors of terrestrial isopods (woodlice). Upon exposure to a source giving 15 times the background level placed at one end of a box, a significant increase in the number of woodlice gathering under the beta-source was observed with time, as compared with the sham control. Terrestrial isopods have chemoreceptors (the olfactory system) on the terminal segment of their antennae. An additional experiment confirmed the involvement of these antennae in the radiation effect on behavior. After the excision of the antennae, no beta-taxis response was observed. The behavior of the group exposed to the source giving 30 times the background tended to decrease gradually in the area of the source, and the individuals aggregated in the area away from the source. Thus, the olfactory sensor in the antennae may be an important organ involved in the prompt response to radiation exposure, and the discrimination of the radiation field strengths of radioisotopes. 相似文献