全文获取类型
收费全文 | 130篇 |
免费 | 2篇 |
国内免费 | 12篇 |
专业分类
安全科学 | 2篇 |
废物处理 | 16篇 |
环保管理 | 8篇 |
综合类 | 35篇 |
基础理论 | 23篇 |
污染及防治 | 44篇 |
评价与监测 | 10篇 |
社会与环境 | 6篇 |
出版年
2023年 | 1篇 |
2022年 | 2篇 |
2021年 | 1篇 |
2018年 | 2篇 |
2017年 | 2篇 |
2016年 | 3篇 |
2015年 | 2篇 |
2014年 | 9篇 |
2013年 | 8篇 |
2012年 | 12篇 |
2011年 | 20篇 |
2010年 | 10篇 |
2009年 | 8篇 |
2008年 | 18篇 |
2007年 | 8篇 |
2006年 | 9篇 |
2005年 | 7篇 |
2004年 | 3篇 |
2003年 | 8篇 |
2002年 | 1篇 |
2000年 | 1篇 |
1998年 | 1篇 |
1996年 | 1篇 |
1995年 | 1篇 |
1993年 | 1篇 |
1990年 | 1篇 |
1984年 | 1篇 |
1982年 | 1篇 |
1981年 | 1篇 |
1979年 | 1篇 |
排序方式: 共有144条查询结果,搜索用时 31 毫秒
1.
Wastewater treatment with multilayer media of waste and natural indigenous materials 总被引:3,自引:0,他引:3
Rahman MA Ahsan S Kaneco S Katsumata H Suzuki T Ohta K 《Journal of environmental management》2005,74(2):107-110
Wastewater treatment using waste materials (refuse concrete, waste paper and charcoal) and natural indigenous rocks (andesite, limestone, granite and nitrolite) in the form of multilayer media was investigated. The removal of suspended solids (SS), phosphate ion, nitrate ion, ammonium ion, toxic metals and chemical oxygen demand (COD) were evaluated for the multilayer wastewater treatment system. Effective removal of heavy metals such as cadmium, chromium, mercury and lead was demonstrated. SS and phosphate ion were removed with relatively high efficiency and the COD after treatment was lessened using certain combinations of media. The present wastewater treatment system is simple, convenient and low cost. Therefore, this method can be applied in small scale plants for wastewater treatment in local and nonexclusive areas. 相似文献
2.
Some polyclads associate with other marine invertebrates such as gastropods, but how these associations evolve is not well understood. This study examined the relationships between a polyclad, Stylochoplana pusilla, and six species of snails in 10 eulittoral sites in Mutsu Bay, northern Japan, in 2010 and 2011. Of the six potential host snail species, Monodonta labio was present at all sites and the prevalence of S. pusilla in the snails’ mantle cavities overall was 82.6 %. Four other snail species occurred at five or six sites in comparable densities, but of these, only Chlorostoma turbinatum and Omphalius rusticus had S. pusilla in their mantle cavities (prevalence of 42.0 and 15.4 %). A congener of M. labio, Monodonta neritoides, occurred at only one site and had no S. pusilla. The mantle, which provides habitat space for S. pusilla, was proportionally the longest in M. labio. In laboratory experiments, the flatworms preferentially entered M. labio over other snail species with the same mantle length. Observed vertical distributions of snails in the littoral zone indicate that M. labio is present in the eulittoral at both high and low tides, while C. turbinatum and O. rusticus are usually found in the sublittoral. In an evolutionary sense, the relationship between S. pusilla and its host may have developed as a mechanism for the flatworm to avoid predation by living in the eulittoral and to avoid desiccation by establishing commensal relationships with certain snails. 相似文献
3.
Akira KONDO Esrom HAMONANGAN Satoshi SODA Akikazu KAGA Yoshio INOUE Masaharu EGUCHI Yuta YASAKA 《环境科学学报(英文版)》2007,19(6):709-713
Total suspended particulate mater (TSP) concentrations were monitored for one year from July 2000 and for one year from April 2003 in Jakarta City. Thirteen elemental TSP components, aluminum (Al), sodium (Na), iron (Fe), lead (Pb), potassium (K), zinc (Zn), titanium (Ti), manganese (Mn), bromine (Br), copper (Cu), chromium (Cr), nickel (Ni), and vanadium (V) were analyzed by a sequential X-ray fluorescence spectrometer. Al, Na, Fe, K, and Pb were major components at most of the sampling locations in 2000. However, only Pb in 2003 dramatically decreased to one tenth. The phase-out of leaded gasoline began on July 1, 2001 in Jakarta City and lead content in gasoline decreased to one tenth, too. The decrease in Pb concentration was a result of the phase-out of leaded gasoline, as lead emissions mainly are exhaust gas from vehicles. 相似文献
4.
The economy of Northeast Thailand is mainly based on agriculture. The transformation of forestlands to agricultural areas and the encroachment of riverbanks within the Phong watershed have caused severe soil erosion. Strong storms in rainy season exacerbate the problem of soil erosion. Difficulty in getting water drives people in the upstream region to live on riverbanks. Soil erosion affects water utility by increasing the turbidity in the Phong River and also by decreasing the water storage capacity of small reservoirs for the upstream residents, as well as that of the Ubolratana Dam. The rate of siltation in the Ubolratana Dam was estimated to be 1.5 million tons/year during 1965-1990. The main source of water supply is surface water in the Phong watershed, and fluctuating turbidity makes water treatment difficult. The maximum turbidity in the upstream Phong River exceeds 5000 NTU, whereas it is reduced to be about 300 NTU at the intake point of Khon Kaen Municipal Water Treatment Plant because the Ubolratana Dam works as a huge clarifier. Khon Kaen Municipal Waterworks has a daily water supply of 72,960 m3/day. The average amounts of alum used in the wet (May-October) and dry (November-April) periods are 42.33 g/m3 and 28.46 g/m3, respectively. The average costs of the amounts of alum used are 0.213 and 0.143 Bahts/m3 during the wet and dry periods, respectively. Fluctuation of turbidity in raw water makes it difficult to adjust alum dose, resulting in treated water quality unstable, and handling of sludge disposal difficult. 相似文献
5.
The AgCl/Al2O3 catalyst has potential for use in the selective catalytic reduction (SCR) of NOx. A compound hydrocarbon, following
oxygenation is used as a type of reducing agent. In this experiment, the AgCl/Al2O3 catalyst was produced by four different methods,
and the differences among their reduction catalysis of NOx were compared. Ethanol was used as a type of reducing agent. X-ray
diffraction analysis was performed to study the crystalline structure and scanning electron microscope and transmission electron
microscope (TEM) were applied to determine the microindentation. The results indicated that, in the range of 350–400°C, there was
no significant difference on the NOx reduction rate; however, there was dispersion at high and low temperature ranges. The size of the
AgCl particles was about 20–100 nm. 相似文献
6.
Virtually all animal conflicts occur over access to mates or resources that affect survival, the two key components of fitness.
In this paper, we report that predation risk and mate defense jointly affect the outcomes of contests between male sand crabs
(Scopimera globosa) for burrows in which crabs mate and take shelter from predators. We observed the contests under three different conditions:
(1) the natural condition of low predation risk and without the presence of a female; (2) the first experiment in which we
imposed upon only intruding males the perception of predation risk—by digging them from their burrows, capturing and handling
them, and placing them into other males’ burrows—to increase the value of the burrows for the intruders as shelter, and (3)
the second experiment in which we repeated this treatment but increased the resource value of the burrow to the resident by
placing a female in his burrow. The difference in body size between contestants was the main determinant of victory in all
analyses. However, perceived predation risk also partly affected the outcomes of the fights: The motivated intruders were
likely to win even when they were a little smaller than the residents. In addition, defense of a female had a significant
effect on the outcomes of fights: The motivated residents won more fights than the motivated intruders, indicating that these
two treatments caused asymmetric increases of the resource value. This is the first report of two external factors simultaneously
raising resource value, affecting motivation of contestants, and altering the outcome of fights. 相似文献
7.
Hajime Yasuda Tohru Kamo Mariko Adachi Satoshi Sajima Hideki Nakagome 《Journal of Material Cycles and Waste Management》2010,12(2):123-127
The rapid hydropyrolysis of model compounds for epoxy resin oligomers and biomass tar was carried out in a hydrogen atmosphere
at 1073 K and 973 K. The assumed oligomers were partially pyrolyzed epoxy resin with biomass tar as solvent for the resin.
The product distributions obtained from rapid hydropyrolysis of phenol and bisphenol-A are shown. We also discuss the effects
of reaction temperature and hydrogen partial pressure on the product yield. In particular, more phenol was produced from bisphenol-A
at 973 K than at 1073 K. The yield of methane, which was the final hydropyrolysis product, increased with increasing hydrogen
partial pressure, whereas benzene and phenol were believed to behave as intermediate products in the hydropyrolysis reaction.
The results suggest that phenol could be obtained with high selectivity from tar by optimizing the reaction conditions. 相似文献
8.
Kikuo Oikawa Hiroko Saito Ikuei Kifune Tatsuo Ohshina Masami Fujii Yukio Takizawa 《Chemosphere》1982,11(9):943-951
To study atmospheric mercury absorption in human respiratory passage-ways, mercury in expired air was measured in three different states of breathing: steady breathing, deep breathing and breath held after inspiration.In this study, air containing mercury was inhaled through the nose and expired through the mouth. The concentration of mercury in the exhaled air was determined by the technique of gold-amalgam trapping, heat vaporization, and flameless atomic absorption measurement.The subjects were 13 male adults, aged 25–62 years, and 38 cases were observed. Four different concentrations of mercury, 1–3, 4–6, 10–11, and 20–30 μg/m3 were used, and absorption for each was determined. When the concentration was 1–3 μg/m3, the absorption was 74–92%, the average being 82.5%. At concentrations of 4–6, 10–11, and 20–30 μg/m3, the absorption was 76.6–100%, 75.5–99.2%, and 79.9–95.9% respectively, and the average was 88.8%, 85.2%, and 87.7% respectively.A slightly higher rate of mercury absorption was observed in deep breathing than in steady breathing, and when expiration was suppressed for some time after inspiration, the rate increased remarkably to 97.4–99.7%. Prolonged retention of inhaled air containing mercury in the respiratory tract is believed to have caused the increased absorption. 相似文献
9.
10.
Male mate choice has recently been reported in some animals with male–male competition. In the laboratory, we examined whether males choose their mates based on female quality that was indicated by body size and/or days to prenuptial molt, and the effects of female quality on male–male competition in the hermit crab Pagurus nigrofascia. We collected samples from April to May 2009 at an intertidal shore in Hokkaido, Japan (41°N, 140°E). When a male simultaneously encountered two receptive females in the mate choice experiment, males chose females which require less time to molt. When a male guarding a female with less time to molt was challenged by an intruder, the guarding male defended the female for a longer period and was more likely to win the contest. These results indicate that male P. nigrofascia use time to molt to discriminate between females. 相似文献