全文获取类型
收费全文 | 1148篇 |
免费 | 109篇 |
国内免费 | 858篇 |
专业分类
安全科学 | 59篇 |
废物处理 | 17篇 |
环保管理 | 81篇 |
综合类 | 793篇 |
基础理论 | 776篇 |
污染及防治 | 277篇 |
评价与监测 | 97篇 |
社会与环境 | 14篇 |
灾害及防治 | 1篇 |
出版年
2023年 | 9篇 |
2022年 | 33篇 |
2021年 | 37篇 |
2020年 | 34篇 |
2019年 | 58篇 |
2018年 | 61篇 |
2017年 | 92篇 |
2016年 | 83篇 |
2015年 | 116篇 |
2014年 | 101篇 |
2013年 | 280篇 |
2012年 | 139篇 |
2011年 | 127篇 |
2010年 | 82篇 |
2009年 | 104篇 |
2008年 | 66篇 |
2007年 | 90篇 |
2006年 | 89篇 |
2005年 | 70篇 |
2004年 | 53篇 |
2003年 | 63篇 |
2002年 | 37篇 |
2001年 | 41篇 |
2000年 | 31篇 |
1999年 | 22篇 |
1998年 | 43篇 |
1997年 | 33篇 |
1996年 | 19篇 |
1995年 | 24篇 |
1994年 | 28篇 |
1993年 | 14篇 |
1992年 | 7篇 |
1991年 | 4篇 |
1990年 | 3篇 |
1988年 | 2篇 |
1987年 | 2篇 |
1986年 | 3篇 |
1985年 | 1篇 |
1984年 | 1篇 |
1983年 | 4篇 |
1981年 | 2篇 |
1980年 | 1篇 |
1979年 | 2篇 |
1978年 | 2篇 |
1977年 | 1篇 |
1975年 | 1篇 |
排序方式: 共有2115条查询结果,搜索用时 609 毫秒
111.
Küster A Pohl K Altenburger R 《Environmental science and pollution research international》2007,14(6):377-383
Background, Goals and Scope During the last years the miniaturization of toxicity test systems for rapid and parallel measurements of large quantities
of samples has often been discussed. For unicellular algae as well as for aquatic macrophytes, fluorescence-based miniaturized
test systems have been introduced to analyze photosystem II (PSII) inhibitors. Nevertheless, high-throughput screening should
also guarantee the effect detection of a broad range of toxicants in order to ensure routinely applicable, high-throughput
measuring device experiments which can cover a broad range of toxicants and modes of action others than PSII inhibition. Thus,
the aim of this study was to establish a fast and reproducible measuring system for non-PSII inhibitors for aquatic macrophyte
species to overcome major limitations for use.
Methods A newly developed imaging pulse-amplitude-modulated chlorophyll fluorometer (I-PAM) was applied as an effect detector in short-term
bioassays with the aquatic macrophyte species Lemna minor. This multiwell-plate based measuring device enabled the incubation and measurement of up to 24 samples in parallel. The
chemicals paraquat-dichloride, alizarine and triclosan were chosen as representatives for the toxicant groups of non-PSII
herbicides, polycyclic aromatic hydrocarbons (PAHs) and pharmaceuticals and personal care products (PPCPs), which are often
detected in the aquatic environment. The I-PAM was used (i) to establish and validate the sensitivity of the test system to
the three non-PSII inhibitors, (ii) to compare the test systems with standardized and established biotests for aquatic macrophytes,
and (iii) to define necessary time scales in aquatic macrophyte testing. For validation of the fluorescence-based assay, the
standard growth test with L. minor (ISO/DIS 20079) was performed in parallel for each chemical.
Results The results revealed that fluorescence-based measurements with the I-PAM allow rapid and parallel analysis of large amounts
of aquatic macrophyte samples. The I-PAM enabled the recording of concentration-effect-curves with L. minor samples on a 24-well plate with single measurements. Fluorescence-based concentration-effect-curves could be detected for
all three chemicals after only 1 h of incubation. After 4–5 h incubation time, the maximum inhibition of fluorescence showed
an 80–100% effect for the chemicals tested. The EC50 after 24 h incubation were estimated to be 0.06 mg/L, 0.84 mg/L and 1.69
mg/L for paraquatdichloride, alizarine and triclosan, respectively.
Discussion The results obtained with the I-PAM after 24 h for the herbicide paraquat-dichloride and the polycyclic aromatic hydrocarbon
alizarine were in good accordance with median effective concentrations (EC50s) obtained by the standardized growth test for
L. minor after 7 d incubation (0.09 mg/L and 0.79 mg/L for paraquat-dichloride and alizarine, respectively). Those results were in
accordance with literature findings for the two chemicals. In contrast, fluorescence-based EC50 of the antimicrobial agent
triclosan proved to be two orders of magnitude greater when compared to the standard growth test with 7 d incubation time
(0.026 mg/L) as well as with literature findings.
Conclusion Typically, aquatic macrophyte testing is very time consuming and relies on laborious experimental set-ups. The I-PAM measuring
device enabled fast effect screening for the three chemicals tested. While established test systems for aquatic macrophytes
need incubation times of ≥ 7 d, the I-PAM can detect inhibitory effects much earlier (24 h), even if inhibition of chemicals
is not specifically associated with PSII. Thus, the fluorescence-based bioassay with the I-PAM offers a promising approach
for the miniaturization and high-throughput testing of chemicals with aquatic macrophytes. For the chemical triclosan, however,
the short-term effect prediction with the I-PAM has been shown to be less sensitive than with long-term bioassays, which might
be due to physicochemical substance properties such as lipophilicity.
Recommendations and Perspectives The results of this study show that the I-PAM represents a promising tool for decreasing the incubation times of aquatic macrophyte
toxicity testing to about 24 h as a supplement to existing test batteries. The applicability of this I-PAM bioassay on emergent
and submerged aquatic macrophyte species should be investigated in further studies. Regarding considerations that physicochemical
properties of the tested substances might play an important role in microplate bioassays, the I-PAM bioassay should either
be accompanied by evaluating physicochemical properties modeled from structural information prior to an experimental investigation,
or by intensified chemical analyses to identify and determine nominal concentrations of the toxicants tested. The chemicals
paraquat-dichloride, alizarine and triclosan were chosen as representatives for the toxicant groups of non-PSII herbicides,
PAHs and PPCPs which are often detected in the aquatic environment. Nevertheless, in order to ensure a routinely applicable
measuring device, experiments with a broader range of toxicants and samples of surface and/or waste waters are necessary.
ESS-Submission Editor: Dr. Markus Hecker (MHecker@Entrix.com) 相似文献
112.
113.
Recycling and conservation efforts for water are the need of the day because of the lack of new water sources and the ever-increasing
demand for drinking water. Seedlings of Acacia nilotica L. were irrigated with: canal water (T1, control); municipal effluent (T2); textile effluent (T3); steel effluent (T4); textile + municipal effluent in 1:1 ratio (T5); steel + municipal effluent in 1:2 ratio (T6); steel + textile in 1:2 ratio (T8) and steel + municipal + textile in 1:2:2 ratio (T7) with views to observe effluents effect on the seedlings and its adaptability and to recommend safe disposal of these effluents.
Seedlings in T6, T7 and T8 showed 50% lesser height and collar diameter than those in control. Seedlings in T2 attained greatest height, collar diameter, numbers of branches and produced 140 g dry biomass seedling−1. Highest concentration of manganese (Mn), iron (Fe), copper (Cu) and zinc (Zn) and lowest concentration of nitrogen (N),
phosphorus (P), potassium (K), calcium (Ca) and magnesium (Mg) in the seedlings of T4, T6, T7 and T8 resulted in nutritional imbalance, mineral toxicity and reduction in photosynthetic (Pn) and transpiration (E) rates and caused seedling mortality. Seedlings of T3 had highest sodium concentration and low concentration of Ca, Mg and micronutrients resulting in nutritional imbalance, augmented
chlorosis and reduced gas exchange and biomass by half as compared to control. Increased growth, Pn and E and biomass in seedlings of T5 over T3 and survival period in T6, T7 and T8 seedlings suggested a beneficial effect of effluents mixing. Unscientific disposal should be avoided and toxic concentration
of metal ions␣may be reduced for long-term application and harmless disposal of effluents in afforestation and urban development. 相似文献
114.
Erik Krznaric Jan H.L. Wevers Jaco Vangronsveld 《Environmental pollution (Barking, Essex : 1987)》2009,157(5):1581-1588
Soil metal pollution can trigger evolutionary adaptation in soil-borne organisms. An in vitro screening test showed cadmium adaptation in populations of Suillus luteus (L.: Fr.) Roussel, an ectomycorrhizal fungus of pine trees. Cadmium stress was subsequently investigated in Scots pine (Pinus sylvestris L.) seedlings inoculated with a Cd-tolerant S. luteus, isolated from a heavy metal contaminated site, and compared to plants inoculated with a Cd-sensitive isolate from a non-polluted area. A dose-response experiment with mycorrhizal pines showed better plant protection by a Cd-adapted fungus: more fungal biomass and a higher nutrient uptake at high Cd exposure. In addition, less Cd was transferred to aboveground plant parts. Because of the key role of the ectomycorrhizal symbiosis for tree fitness, the evolution of Cd tolerance in an ectomycorrhizal partner such as S. luteus can be of major importance for the establishment of pine forests on Cd-contaminated soils. 相似文献
115.
Tatsuya Kunisue 《Environmental pollution (Barking, Essex : 1987)》2009,157(3):910-915
Polychlorinated naphthalenes (PCNs) are persistent, bioaccumulative, and toxic contaminants. Prior to this study, the occurrence of PCNs in human adipose tissues from the USA has not been analyzed. Here, we have measured concentrations of PCNs in human adipose tissue samples collected in New York City during 2003-2005. Concentrations of PCNs were in the range of 61-2500 pg/g lipid wt. in males and 21-910 pg/g lipid wt. in females. PCN congeners 52/60 (1,2,3,5,7/1,2,4,6,7) and 66/67 (1,2,3,4,6,7/1,2,3,5,6,7) were predominant, collectively accounting for 66% of the total PCN concentrations. Concentrations of PCNs in human adipose tissues were 2-3 orders of magnitude lower than the previously reported concentrations of polychlorinated biphenyls (PCBs) and polybrominated diphenyl ethers (PBDEs). Concentrations of PCNs were not correlated with PCB concentrations. The contribution of PCNs to dioxin-like toxic equivalents (TEQs) in human adipose tissues was estimated to be <1% of the polychlorinated dibenzo-p-dioxin/dibenzofuran (PCDD/F)-TEQs. 相似文献
116.
Study on Fish and Amphibian Embryo-Larval Toxicity Test 总被引:1,自引:0,他引:1
Zhang Tong 《Environmental monitoring and assessment》1999,55(3):363-369
In China, it is necessary to establish short-term biomonitoring methods for evaluating the chronic toxicity of industrial wastewater. In this paper, the aquatic toxicity of four important pollutants in petrochemical wastewater, including acrylonitrile, acetonitrile, sulphocyanic sodium and dimethyl formamide, was studied with fish and amphibian embryo-larval toxicity tests using Cyprinus carpio and Rana nigromaculata as test organisms. The objective is to present some useful data for establishing short-term chronic toxicity test methods used to perform biomonitoring in China. The results indicate that the chronic toxicity of acrylonitrile to fish and amphibians was the highest of the four test pollutants, followed by NaSCN, acetonitrile and DMF. The sensitivity of the carp embryo- larval test to chemicals was greater than that of the R. nigromaculata embryo-larval test. 相似文献
117.
118.
119.
1—硝基芘对斜生栅藻的毒性研究 总被引:2,自引:2,他引:0
酿要用评价化学品对藻类毒性的标准实验方法,研究了1-硝基芘对斜生栅藻生长的影响,得到了1-NP抑制斜生栅藻生长的EC50(96h)为0.1824mg.1^-1,实验结果还表明,1-NP对藻生长的抑制作用随时间的延长而增加,抑制物性表现为特久且强度大,抑制机理为不可逆性抑制。 相似文献
120.