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71.
Abstract

Comprehensive field studies were initiated in 2002 to measure emissions of ammonia (NH3), hydrogen sulfide (H2S), carbon dioxide (CO2), methane (CH4), nonmethane hydrocarbons (NMHC), particulate matter <10 µm in diameter, and total suspended particulate from swine and poultry production buildings in the United States.

This paper focuses on the quasicontinuous gas concentration measurement at multiple locations among paired barns in seven states. Documented principles, used in air pollution monitoring at industrial sources, were applied in developing quality assurance (QA) project plans for these studies. Air was sampled from multiple locations with each gas analyzed with one high quality commercial gas analyzer that was located in an environmentally controlled on-farm instrument shelter. A nominal 4 L/min gas sampling system was designed and constructed with Teflon wetted surfaces, bypass pumping, and sample line flow and pressure sensors. Three-way solenoids were used to automatically switch between multiple gas sampling lines with ≥10 min sampling intervals. Inside and outside gas sampling probes were between 10 and 115 m away from the analyzers. Analyzers used chemiluminescence, fluorescence, photoacoustic infrared, and photoionization detectors for NH3, H2S, CO2, CH4, and NMHC, respectively. Data were collected using personal computer-based data acquisition hardware and software. This paper discusses the methodology of gas concentration measurements and the unique challenges that livestock barns pose for achieving desired accuracy and precision, data representativeness, comparability and completeness, and instrument calibration and maintenance.  相似文献   
72.
In copper based antifouling (AF) paints Cu (I) oxide was largely used as booster biocide. In this study effect of Cu (I) oxide on two marine microalgae, Tetraselmis suecica and Dunaliella tertiolecta was demonstrated. EC50 (96 hr) concentrations estimated for T. suecica and D. tertiolecta were 1.3 mg l(-1) and 1.34 mg l(-1), respectively. Copper (I) oxide induced changes in growth, chlorophyll, carbohydrate and protein contents were observed in T. suecica and D. tertiolecta. At low concentration of 0.0625 mg l(-1), 3-26% and 1-16% growth stimulation was observed in T. suecica and T. tertiolecta respectively. Increasing Cu (I) oxide concentrations proportionately decreased the carbohydrate and protein contents. This study clearly indicates the toxicity of excessive Cu (I) oxide on growth and biochemical compositions of T. suecica and D. tertiolecta.  相似文献   
73.
Water from 15 sampling stations in Tasik Chini (Chini Lake), Peninsular Malaysia were sampled for 12 months from September 2004 until August 2005 and analyzed for 11 metals including iron (Fe), aluminum (Al), manganese (Mn), barium (Ba), zinc (Zn), lead (Pb), copper (Cu), cadmium (Cd), nickel (Ni), chromium (Cr) and cobalt (Co). Results showed that the mean (min-max) metal concentrations (in micrograms per liter) in Tasik Chini waters for the 12 months sampling based on 15 sampling stations (in descending order) for Fe, Al, Mn, Ba, Zn, Pb, Cu and Cd were 794.84 (309.33-1609.07), 194.53 (62.37-665.93), 29.16 (16.68-79.85), 22.07 (15.64-29.71), 5.12 (2.224-6.553), 2.36 (1.165-4.240), 0.832 (0.362-1.443) and 0.421 (0.254-0.696) respectively. Concentration for three metals i.e. Ni, Cr and Co were too low and not detected by the graphite furnace Atomic Absorption Spectrophotometry (AAS). Comparison with various water quality standards showed that the mean metals concentration in surface water of Tasik Chini were low and within the range of natural background except for Fe and Al. In general, metal concentrations in Tasik Chini water varied temporally and spatially. The main factors influencing these metal concentrations in the water were the raining season and mining activities. Stations located at Tanjung Jerangking and Melai areas were the most effected due to those factors.  相似文献   
74.
75.
The occurrence of some veterinary medicines in the livestock wastewater plants (WWTPs) was investigated. This investigation represented the occurrence of veterinary medicines to treat in the livestock WWTPs or be discharged into the water system in Korea since the sampling sites were widely distributed across the nation and samples were collected from the 11 livestock WWTPs. Nine antibiotics, two analgesics, and two disinfectants occurred in the livestock wastewater plants (WWTPs). From 11 livestock WWTP influents, chlortetracycline, oxytetracycline, acetylsalicylic acid, and disinfectants frequently occurred with the high concentrations. Meanwhile, sulfamethoxazole, erythromycin-H2O, and trimethoprim did not occur during sampling periods. The values for log Kow of each chemical showed a high correlation with the number of hydrogen bonding acceptors and were important parameters to estimate and understand the biodegradability and toxicity of a compound in the environment. The biodegradability of each compound was proportional to the hydrophilicity of each compound and the toxicity was proportional to the number of hydrogen bonding acceptors of each compound. The expected introductory concentration (EIC), predicted exposure concentration (PEC), and hazard quotient showed that the livestock WWTP effluents were hazardous to ecosystems.  相似文献   
76.
The Philippine fisheries accounted for 3.7% of the gross national product at current prices. The sector employed about 990,872 persons. Of the divisions comprising the industry, municipal fisheries continued to contribute the largest share of fish production. However, the sector is beset with problems, many of which are best examplified by the case of San Miguel Bay (SMB). This paper presents the problems and constraints confronting SMB, a common property resource. This bay's open access condition has led to various problems, such as declining fishery resources, depressed socioeconomic conditions, illegal fishing, increasing population, and conflict among resource users. A poor marketing system, low level of fishing technology, fishermen's noncompliance and authorities' lax enforcement of rules and regulations, as well as lack of alternative sources of income further characterize the condition in SMB. Establishment of fishing rights, improvement of the marketing system, provision of alternative sources of income, and improvement of fishing technology were some of the solutions suggested. One major constraint, however, is financial, Comanagement complemented with other management tools has been proposed in addressing the problems in SMB.  相似文献   
77.
This study assessed the daily exposure to dioxin using comparable approach methods in order to predict the human health risks of dioxin on the general adult population and incinerator workers in Korea. The health risk assessment of dioxin involved four scenarios (General-Direct, General-Breast Milk, General-Blood, and Worker-Blood). The risks were described in terms of the excess cancer risk and the MOEs (Margin-Of-Exposure) for cancer, reproductive dysfunctions, endometriosis, and neurobehavioral effects. The adult daily intake (General-Direct) of dioxin was estimated to be 0.50 pg-TEQ/kg-day based on the dioxin concentrations in the environmental media and foods in Korea. The average dioxin concentrations in General-Breast Milk, General-Blood, and Worker-Blood were 15.13 pg-TEQ/g fat, 14.57 pg-TEQ/g lipid, and 22.90 pg-TEQ/g lipid, respectively. The lifetime average daily doses (LADDs) of dioxin for General-Breast Milk, General-Blood, and Worker-Blood were estimated to be 1.35 pg-TEQ/kg day, 0.99 pg-TEQ/kg day, and 1.15 pg-TEQ/kg day, respectively. Although the estimated risks of cancer and reproductive dysfunctions were not unusually high in any of the four scenarios, the MOE values for the neurobehavioral effects on infants were not sufficiently high to guarantee the safety against this endpoint.  相似文献   
78.
Georgetown of Penang, an old city, is noted for its narrow streets. The existing traffic dispersal system is utterly inadequate to cope with the ever increasing number of cars and motorcycles on the road. The principal objective of this study is to build prediction models of CO to be employed as one of the planning tools in the future design of Penang urban traffic dispersal system. This study involves the monitoring of kerbside CO levels at selected sites and the fitting of hourly-averaged CO data to linear regression models incorporating the residual effect of CO emission due to traffic in the earlier periods and also different categories of vehicles. The best overall regression model appears to be the one based upon the total traffic count of motorcycles. This can be accounted for by the fact that the traffic counts of motorcycles and cars are highly correlated in most cases and that the emissions of CO from motorcycles are more readily detected as they travel closer to the kerb. The inclusion of residual CO in the models significantly improves the correlation coefficient from about 0.4 to about 0.7.  相似文献   
79.
Samples of the hermatypic coralGalaxea fascicularis were collected between April 1987 and April 1990 from coral reefs off Singapore (103 °45E; 1 °13N). Ca2+-activated adenosine triphosphatase (ATPase) activity was detected in the plasma-membrane-enriched heavy microsomal fraction ofG. fascicularis. The high affinity component hadKm andVmax values of 0.0021 mM and 0.050 µmol Pi mg–1 protein min–1, respectively; corresponding values for the low affinity component were 0.15 mM and 0.85 µmol mg–1 protein min–1. The activity of the high affinity component was inhibited 80 and 50%, respectively, by the anticalmodulin drugs calmidazolium and chlorpromazine. The low affinity component of the Ca2+-ATPase may represent activities of alkaline phosphatase, Ca2+-ATPase from membranes of mitochondria and endoplasmic reticulum, or calmodulin-dissociated plasma membrane Ca2+-ATPase resulting from the removal of Ca2+ by EDTA during the isolation process. The high affinity Ca2+-ATPase is probably the enzyme responsible for Ca2+ extrusion from the cells ofG. fascicularis. The high and low affinity components of this Ca2+-ATPase could use ATP and ADP as substrates. Maximum activities of both components were registered at pH 7 and at 45°C. Ruthenium red, a specific inhibitor of Ca2+-ATPase, inhibited the activities of the high and low affinity Ca2+-ATPase by 100 and 60%, respectively. Inhibition of the activities of both components was also observed with sulphydryl reagents (PCMB and mersalyl). However, DCMU, diamox, dinitrophenol, iodoacetate, fluoride, cyanide, ouabain, oligomycin B and L-phenylalanine had no effect on the enzyme activities.  相似文献   
80.
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