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551.
Atmospheric aerosol particles and metallic concentrations, ionic species were monitored at the Experimental harbor of Taichung
sampling site in this study. This work attempted to characterize metallic elements and ionic species associated with meteorological
conditions variation on atmospheric particulate matter in TSP, PM2.5, PM2.5–10. The concentration distribution trend between TSP, PM2.5, PM2.5–10 particle concentration at the TH (Taichung harbor) sampling site were also displayed in this study. Besides, the meteorological
conditions variation of metallic elements (Fe, Mg, Cr, Cu, Zn, Mn and Pb) and ions species (Cl−, NO3
−, SO4
2−, NH4
+, Mg2+, Ca2+ and Na+) concentrations attached with those particulate were also analyzed in this study. On non-parametric (Spearman) correlation
analysis, the results indicated that the meteorological conditions have high correlation at largest particulate concentrations
for TSP at TH sampling site in this study. In addition, the temperature and relative humidity of meteorological conditions
that played a key role to affect particulate matter (PM) and have higher correlations then other meteorological conditions
such as wind speed and atmospheric pressure. The parameter temperature and relative humidity also have high correlations with
atmospheric pollutants compared with those of the other meteorological variables (wind speed, atmospheric pressure and prevalent
wind direction). In addition, relative statistical equations between pollutants and meteorological variables were also characterized
in this study. 相似文献
552.
Whole effluent toxicity (WET) tests, with Daphnia magna and Selenastrum capricornutum, were introduced to evaluate the biological toxicities of effluents from the wastewater treatment plants (WWTPs) in Korea.
In WET tests of WWTPs effluents, 33.3% (33/99) for D. magna and 92.6% (75/81) for S. capricornutum revealed greater than 1 toxic unit (TU), even though all the treatment plants investigated were operating in compliance with
the regulations, as assessed using conventional monitoring methods (i.e., BOD and total concentration of N or P, etc). There
were only minor differences in toxicities according to the types of influents (municipal and agro-industrial) in all treatment
plants. However, the effluents treated by an activated sludge treatment process were found to exhibit significantly lower
toxicity than those treated by rotating biological contactor (RBC) and extended aeration processes. The seasonal variations
in the toxicity were lower in the summer compared to winter, which may have been due to the rainfall received to the sewage
intake system during the former period. The impact of WET on river water was also investigated based on the discharge volume.
At sites A and B, the total impact of toxicity to stream and river waters was observed to be 70.9% and 90.4% for D. magna and S. capricornutum, respectively. The other four small treatment plants (sites F, G, H and I), with relative discharging volumes between 0.001
and 0.002, contribute less than 1% to the total toxicity. 相似文献
553.
Lu LT Chang IC Hsiao TY Yu YH Ma HW 《Environmental science and pollution research international》2007,14(1):49-59
Background Since the 1970s, at least 200 hectares (ha) of farmland has been polluted by the heavy metal cadmium (Cd).Consequently, the
Cd pollution has led to contaminate the rice production and caused acute social panic. According to the recent investigation
results performed by the Taiwan Environmental Protection Administration (TEPA), it is indicated that most of the Cd pollution
incidents in Taiwan resulted from the wastewater discharge of stearate Cd factories. To prevent the Cd pollution incidents
from spreading, the TEPA has either forced these factories to close down or assisted them in improving their production processes
since the 1980s. Unfortunately, accidental incidents of Cd pollution still emerge in an endless stream, despite the strict
governmental controls placed on these questionable factories. Whether this pollution has resulted from undetected or hidden
pollution sources stemming from two decades ago or comes from some new source, will be an outstanding issue. Therefore, this
study attempts to identify the pollution sources of Cd in soil in Taiwan as well as to find the solution to the above-mentioned,
outstanding issue by way of a methodology termed Material Flow Analysis (MFA).
Method logy. The MFA has proved to be a useful tool on providing quantitative information of the flow of substances through an economic
to an environmental system. Based upon the supply-and-demand theory of MFA, researchers have successfully conducted an overview
of the use of materials in many industries, the construction industry being one of these. Therefore, this study tries to establish
a set of analytical processes by way of MFA for identifying the pollution source of Cd in soil in Taiwan. In addition, the
spirit of Life Cycle Analysis (LCA) technique was also employed to identify the materials, and products should be ignored
as a crucial pollution source in this study.
Results and Discussion According to the MFA methodology applied in this study and on the basis of related studies performed by Taiwanese governmental
authorities, we arrive at the following analysis results: (1) the total amount of Cd from the economic perspective of material
and product flow was approximately 441.2 tons; (2) the wastewater directly discharged into irrigation water can be concluded
to be the major pollution route of Cd in farmland soil in Taiwan; (3) material plastic stabilizer (cadmium oxide, CdO), Zn-Pd
compounds and Cu compounds should be the crucial pollution sources to contaminate environment through the route of wastewater
in Cd flow analysis; (4) the crucial pollution sources to contaminate environment through the route of wastewater in Cd flow
analysis were five factories, Coin, Jili, Taiwan Dye, Guangzheng and Mingguan, and they were all categorized as stearate Cd
industries; (5) the typical source of the Cd pollution in soil in Changhua County through the pollution route of wastewater
should be the metal surfacing process industries.
Conclusions This study proved that MFA can be a good tool for identifying Cd flow as well as for recognizing the crux of the problem
concerning incidents of Cd pollution. This study led to the conclusion that the causal relationship between farmland pollution
caused by Cd and stearate Cd factories in Taiwan seemed quite close by way of MFA methodology. In addition, this study also
found that the wastewater discharged from a single metal surfacing process factory will not cause remarkable farmland pollution.
However, the wastewater simultaneously discharged from a group of pollution factories can result in a significant pollution
incident.
Recommendations and Outlook This case study is only a small contribution to the understanding of the toxic material flow related to Cd in the environment.
This study recommends that Taiwanese governmental authorities should not deal with problems on an ad hoc basis, but should
instead deal with Cd pollution problems overall employing control measures. Finally, the more accurate information or data
we can collect, the more reliable results we can identify. Therefore, the quality and quantity of related data used in this
MFA model should be closely scrutinized in order to ensure the most correct and comprehensive investigation on the toxic material
flow. 相似文献
554.
555.
Hydrological responses and pollutant exports are always highly related to rainfall characteristics. Many studies have demonstrated that the influence of moving rainstorm on flows and mass transport process in hydrologic systems cannot be ignored. Best management practices (BMPs) are popularly applied for controlling water quantity and water quality in a watershed. Since the movements of rainstorm can influence watershed responses, BMP placement strategies should be suitably adjusted in different moving rainstorms. This study designed an intermediate rainfall pattern with varied movement behavior and tried to find the optimal BMP placement strategies, which cannot only satisfy environmental standards but also improve economic benefits, for the rainfall events. The result shows that the control efficiency of pollutant and runoff can highly improve when the BMPs are set near the outlet of a watershed. Since the economic efficiency is always regarded as an important factor, the BMP placement strategy is significant for watershed conservation and management. 相似文献
556.
H. H. Chang H. H. Tung C. C. Chao G. S. Wang 《Environmental monitoring and assessment》2010,162(1-4):237-250
In this study, water samples were collected from 86 water treatment plants for analysis of haloacetic acids (HAAs) and trihalomethanes (THMs) from February to March, 2007 and from July to August, 2007. Both seasonal and geographical variations of disinfection by-products (DBPs) in drinking water of Taiwan were presented. The results showed that the five HAA concentrations (HAA5) were 1.0–38.9 μg/L in the winter and 0.2–46.7 μg/L in the summer; and the total THMs were ND-99.4 μg/L in the winter and ND-133.2 μg/L in the summer. For samples taken from the main Taiwan island, dichloroacetic acid (29.4–31.7%) and trichloroacetic acid (25.3–27.6%) were the two major HAA species, and trichloromethane was the major THM species (49.9–62.2%) in finished water. For water treatment plants located on the offshore islands outside of Taiwan, high bromide concentration was found in raw water, and higher percentage of brominated THMs and HAAs were formed in the overall formation. A statistically significant (P?<?0.005) logarithmic linear regression model was found to be useful to describe the correlations between TTHM and HAA5 or nine HAAs (HAA5?=?1.219 ×TTHM 0.754, R 2?=?0.658; HAA9?=?1.824 ×TTHM 0.735, R 2?=?0.678). No apparent difference was observed for DBPs concentrations between finished water and distribution samples in this study. 相似文献
557.
Do Guen Yoo Dong Eil Chang Hwandon Jun Joong Hoon Kim 《Environmental monitoring and assessment》2012,184(12):7309-7322
It is essential to select the optimal pressure gauge location for effective management and maintenance of water distribution systems. This study proposes an objective and quantified standard for selecting the optimal pressure gauge location by defining the pressure change at other nodes as a result of demand change at a specific node using entropy theory. Two cases are considered in terms of demand change: that in which demand at all nodes shows peak load by using a peak factor and that comprising the demand change of the normal distribution whose average is the base demand. The actual pressure change pattern is determined by using the emitter function of EPANET to reflect the pressure that changes practically at each node. The optimal pressure gauge location is determined by prioritizing the node that processes the largest amount of information it gives to (giving entropy) and receives from (receiving entropy) the whole system according to the entropy standard. The suggested model is applied to one virtual and one real pipe network, and the optimal pressure gauge location combination is calculated by implementing the sensitivity analysis based on the study results. These analysis results support the following two conclusions. Firstly, the installation priority of the pressure gauge in water distribution networks can be determined with a more objective standard through the entropy theory. Secondly, the model can be used as an efficient decision-making guide for gauge installation in water distribution systems. 相似文献
558.
Lauren Nozomi Marques Yabuki Camila Destro Colaço Amauri Antonio Menegário Roberto Naves Domingos Chang Hung Kiang Domitila Pascoaloto 《Environmental monitoring and assessment》2014,186(2):961-969
Studies concerning the lability and bioavailability of trace metals have played a prominent role in the search for contamination of water resources. This work describes the first application yet of the diffusive gradients in thin films technique (DGT) to the determination of the fraction of free plus labile metals in waters from the Amazon Basin. Due to the complexity of the use of DGT for samples with low ionic strength and high organic matter content (characteristic of Amazonian rivers), a new analytical procedure was developed. The method is based on the determinations of apparent diffusion coefficients (Dap) in the laboratory, by performing deployments in samples collected in the corresponding sites of study. The Dap thereby determined is then used for in situ measurements. The suitability of the proposed approach for determination of labile Al, Cd, Co, Cu, Mn, Ni, and Zn in the Amazon River and Rio Negro (English: Black River) was evaluated. Except for Co, Mn (in a deployment at Rio Negro), Ni and Zn (in a deployment at Amazon River), labile in situ measurements were lower or similar to dissolved concentrations, indicating suitability of the proposed approach. 相似文献
559.
A proper water quality monitoring design is required in a watershed, particularly in a water resource protected area. As numerous factors can influence the water quality monitoring design, this study applies multiple criteria analysis to evaluate the suitability of the water quality monitoring design in the Taipei Water Resource Domain (TWRD) in northern Taiwan. Seven criteria, which comprise percentage of farmland area, percentage of built-up area, amount of non-point source pollution, green cover ratio, landslide area ratio, ratio of over-utilization on hillsides, and density of water quality monitoring stations, are selected in the multiple criteria analysis. The criteria are normalized and weighted. The weighted method is applied to score the subbasins. The density of water quality stations needs to be increased in priority in the subbasins with a higher score. The fuzzy theory is utilized to prioritize the need for a higher density of water quality monitoring stations. The results show that the need for more water quality stations in subbasin 2 in the Bei-Shih Creek Basin is much higher than those in the other subbasins. Furthermore, the existing water quality station in subbasin 2 requires maintenance. It is recommended that new water quality stations be built in subbasin 2. 相似文献
560.