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51.
52.
William R. Stanley 《The Environmentalist》2012,32(3):339-345
Much of the world lacks sufficient rainfall to regularly replenish aquifers and surface storage or receives excessive rainfall resulting in serious erosion and health issues by way of water-borne diseases. Residents adjust to these climatic realities in different ways. Desert peoples have learned to conserve water in order to sustain the minimal potable water requirements and agricultural-animal husbandry development necessary for life. In one country, this finely tuned balance between supply and demand has been negatively impacted by political and economic decisions to encourage agricultural exports by mining subsurface fossil aquifers. Governments in tropical regions have been guilty of neglect or worse by failing to provide their peoples with the tools necessary for obtaining safe drinking water. In the former case, mining of subsurface water threatens the very future existence of society. In at least one tropical country, over dependence upon outside agencies to provide what government might best prioritize for its own funding has caused a disconnect between donor expectations and local realities thus delaying eradication of easily preventable diseases. 相似文献
53.
Foraging guilds of North American birds 总被引:2,自引:0,他引:2
Richard M. De Graaf Nancy G. Tilghman Stanley H. Anderson 《Environmental management》1985,9(6):493-536
We propose a foraging guild classification for North American inland, coastal, and pelagic birds. This classification uses a three-part identification for each guild—major food, feeding substrate, and foraging technique—to classify 672 species of birds in both the breeding and nonbreeding seasons. We have attempted to group species that use similar resources in similar ways. Researchers have identified foraging guilds generally by examining species distributions along one or more defined environmental axes. Such studies frequently result in species with several guild designations. While the continuance of these studies is important, to accurately describe species' functional roles, managers need methods to consider many species simultaneously when trying to determine the impacts of habitat alteration. Thus, we present an avian foraging classification as a starting point for further discussion to aid those faced with the task of describing community effects of habitat change. 相似文献
54.
Stanley A. Changnon 《Journal of the American Water Resources Association》1982,18(5):857-861
ABSTRACT: Accurate forecasting of heavy rainstorms that affect the Chicago Metropolitan area and lead to the undesirable release of storm runoff into Lake Michigan is a major objective. These releases (overflows) were found to be produced by storm events yielding 2 inches or more in a few hours, although only 24 percent of such ≥ 2-inch storms in the area during 1948-1981 produced overflows. Failure to forecast properly or to be able to react to these 2-inch overflow producing events has occurred most often in the spring and fall, although relatively often in June and July in recent years. These overflows have exhibited an inexplicable trebling during 1972-1981 without an increase in ≥ 2-inch storm events. This type of troublesome storm can be reliably predicted, using a recently developed radar man forecast system for the Chicago area. 相似文献
55.
Insect immunology is an active research arena, however, the vast majority of research in the area is conducted on model species
taken from laboratory cultures. We tested the hypothesis that insects are regularly exposed to infections or invasions in
nature and here report results of a field study designed to assess the extent of natural infections in insects collected from
agrarian fields surrounding Kahramanmaraş, Turkey. Specimens were dissected to assess numbers of nodules. Formation of darkened,
melanotic nodules is the predominant cellular immune reaction to microbial and parasitic infection, and once formed, the nodules
are permanently attached to internal surfaces. The collected insects were healthy. Of the >400 examined specimens, at least
some nodules were found in 98%. Numbers of nodules ranged from ∼2/individual to >100 nodules/individual. We conclude that
insects are regularly challenged by microbial and parasitic infections from which they recover. The novel implication of our
data is that insect immune systems may limit the host range and effectiveness of agents deployed in biological control programs.
Knowledge of insect immune systems may contribute to increased use of biopesticides globally. 相似文献
56.
William J. Stanley 《Journal of the Air & Waste Management Association (1995)》2013,63(2):100-101
The search for ways of reducing vehicular emissions has led to numerous investigations of the relationships between fuel composition and the pollutants discharged from automobiles. The most obvious fuel effects result from evaporation of gasoline components from the fuel tanks and carburetors of vehicles which lack effective mechanical devices (such as those required on all 1971 model cars) to control evaporative losses. Thus, several laboratories and cooperative study groups (Coordinating Research Council and American Petroleum Institute) have investigated the ways in which fuel properties (especially the amounts and types of C4-C5 hydrocarbons) influence both the amount and the potential atmospheric reactivity of evaporative emissions.1–6 But fuel evaporation accounts for only a small portion of the total hydrocarbons emitted by automobiles, and gasoline modifications (such as volatility reductions) that reduce evaporative losses can lead to higher levels of hydrocarbons in automobile exhaust.4–6 相似文献
57.
Delbert S. Barth Stanley M. Blacker 《Journal of the Air & Waste Management Association (1995)》2013,63(8):769-771
The U.S. Environmental Protection Agency's program to assess the public health significance of diesel emissions is described. The reasons for the EPA concern over diesel exhaust products are discussed. Some results of EPA research efforts over the last nine months are summarized and preliminary conclusions are drawn. Finally, the planned future health experiments which will hopefully fill some remaining gaps in our knowledge are identified. 相似文献
58.
Alan J. Hoffman Stanley F. Sleva William M. Cox 《Journal of the Air & Waste Management Association (1995)》2013,63(7):704-707
The National Ambient Air Quality Monitoring Program is carried out by state and local air pollution control agencies in support of their State Implementation Plans (SIP’s). The current EPA regulations which specify the characteristics of these state monitoring programs are undergoing change as a result of a comprehensive review by an independent work group. These revised regulations, which are described in the paper, are intended to improve the quality, timeliness, and usability of the data generated by the states for all data users. In addition, the revised regulations seek to bring about; (a) national consistency in monitoring site locations through standardized siting procedures; (b) improved network operations by means of a minimum quality assurance program; (c) reduced network inflexibility through an annual network review process; and (d) reduced data reporting through changed data reporting procedures. 相似文献
59.
Abstract Title III of the 1990 Clean Air Act Amendments designated methanol as a pollutant to be regulated. The U.S. Environmental Protection Agency (EPA), through a contract with Research Triangle Institute, has developed a method for measuring methanol emissions from stationary sources. The methanol sampling train (MST) consists of a glass-lined heated probe, two condensate knockout traps, and three sorbent cartridges packed with Anasorb® 747. Samples are desorbed with a 1:1 mixture of carbon disulfide (CS2) and N, N-dimethylformamide (DMF). Condensate water and CS2/ DMF samples are analyzed by gas chromatography with flame ionization detection. The MST has a practical quantitation limit of approximately 3 ppm for a 20-L sample. Samples were shown to be stable for at least two weeks after collection. Field tests of the MST and the National Council of the Paper Industry for Air and Stream Improvement (NCASI) methanol sampling method were conducted at two pulp and paper mills. Sampling and analysis procedures followed EPA Method 301 requirements. The sampling location for the first field test was the inlet vent to a softwood bleach plant scrubber, where the methanol concentration was approximately 30 ppm. The mean recovery of spike was 108.3% for the MST method and 81.6% for the NCASI method. Although neither method showed significant bias at the 95% confidence level, the betweenmethods bias was significantly different. A second field test was conducted at a vent from a black liquor oxidation tank where the methanol concentration was approximately 350 ppm. Mean spike recoveries were 96.6 and 94.2% for the MST and NCASI methods, respectively. The biases of the two methods and the between-methods bias were not significantly different for the second field test. 相似文献
60.
The Nasty Necessity: Eradicating Exotics 总被引:1,自引:0,他引:1
Stanley A. Temple 《Conservation biology》1990,4(2):113-115