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41.
ABSTRACT: ERTS-1 satellite imagery has been evaluated as a means of providing useful watershed physiography information. From these data physiographic parameters such as drainage basin area and shape, drainage density, stream length and sinuosity, and the percentage of a watershed occupied by major land use types were obtained in three study areas. The study areas were: (1) Southwestern Wisconsin; (2) Eastern Colorado; and (3) portions of the Middle Atlantic States Using ERTS-1 imagery at 1:250,000 and 1:100,000 scales it was found that drainage basin area and shape and stream sinuosity were comparable (within 10%) in all study areas to physiographic measurements derived from conventional topographic maps at the same scales Land use information can be usefully extracted for watersheds as small as 30 mi2(78 km2) in area. Improved drainage network and density information is obtained from ERTS-1 imagery in dissected areas such as Southwestern Wisconsin, but in heavily vegetated areas (Middle Atlantic States) or areas with little physical relief (Eastern Colorado) low order streams are difficult to detect and the derived drainage densities are significantly smaller than those obtained from standard maps. It is concluded that ERTS-1 imagery can be employed to advantage in mean annual runoff prediction techniques and in providing or maintaining land use information used in the calibration and operation of watershed models.  相似文献   
42.
The behavioral responses of more than 800 mountain goats, comprised of 195 social groups, were recorded during hydroelectric exploration activities (primarily aircraft) in northwestern British Columbia. Four categories of overt response were recorded during case tests, ranging from maintenance activity to severe flight. More than 80 percent (n=667) of the observed goats elicited some form of behavioral stress-response, with 33 percent (n=265) displaying a severe flight response to local rock or plant cover. Multiple regression analysis inferred goat responses to be statistically independent of the time of year, type, and vertical orientation of disturbance and group size. As expected, significant correlations (p≤0.05) existed between distance of disturbance, geographic area, cover availability, and degree of awareness. Responses were stimulated primarily by auditory and secondarily by visual cues. Repeated aerial and ground follow-up surveys documented temporary range abandonment and changing observability indices (habitat use and activity patterns) associated with areas of intense exploration activity. The assessed data offer mitigation possibilities and enable formulation of management guidelines to lessen project impacts during future exploration, construction, and operation phases.  相似文献   
43.
ABSTRACT: A significant portion of all pollutants entering surface waters (streams, lakes, estuaries, and wetlands) derives from non-point source (NPS) pollution and, in particular, agricultural activities. The first step in restoring a water resource is to focus on the primary water quality problem in the watershed. The most appropriate NPS control measures, which include best management practices (BMPs) and landscape features, such as wetlands and riparian areas, can then be selected and positioned to minimize or mitigate the identified pollutant(s). A computer-based decision sup. port and educational software system, WATERSHEDSS (WATER, Soil, and Hydro-Environmental Decision Support System), has been developed to aid managers in defining their water quality problems and selecting appropriate NPS control measures. The three primary objectives of WATERSHEDSS are (1) to transfer water quality and land treatment information to watershed managers in order to assist them with appropriate land management/land treatment decisions; (2) to assess NPS pollution in a watershed based on user-supplied information and decisions; and (3) to evaluate, through geographical information systems-assisted modeling, the water quality effects of alternative land treatment scenarios. WATERSHEDSS is available on the World Wide Web (Web) at http://h2osparc.wq.ncsu.edu .  相似文献   
44.
ABSTRACT: In May 1993, a single-family home and adjoining information center opened to the public at the Desert Botanical Garden in Phoenix, Arizona. Desert House is designed as an example of what can be achieved today using available technology to improve residential water and energy efficiency. The home is expected to reduce water and energy use by 40 percent compared with that for the typical three-bedroom, single-family residence in the Phoenix area. Water-conserving features include: landscape design employing low-water use plants, minimum turf area, mulch around plants to reduce evaporation, and drip irrigation system; spa cover for evaporation reduction; rainwater harvesting; low-flow shower heads, faucets, and toilets; and graywater reuse system. The home will be occupied by a family and monitored for water and energy use by computer. Visitors are able to access real time water and energy use data about the home, as well as tour the information center, technical exhibits, surrounding landscape, and the home when it is open (one afternoon a week).  相似文献   
45.
ABSTRACT: Groundwater pumping constitutes approximately 100 percent of the water supply in the Tucson Active Management Area (AMA), Arizona. The current annual overdraft approaches 250,000 acre-feet, but the goal of the AMA is to eliminate the overdraft by the year 2025. Urban water reuse, if implemented by only 30 percent of the area's projected population, would reduce the annual ground-water overdraft by 25,000 acre-feet.  相似文献   
46.
The aim of this paper is to describe indoor microclimate monitoring at two different locations, Sandham Memorial Chapel, in Hampshire, England, and the castle El Alcázar, in Segovia, Spain. Piezoelectric quartz crystal sensors with novel humidity sensitive poly(ethyleneimine) coatings and Pt resistance thermometers were used to measure the relative humidity (RH) and temperature gradients across one of the paintings of the British artist, Stanley Spencer, housed in Sandham Memorial Chapel. The measurement period extended from December 1997 to September 1998. Each coated crystal was set in its own housing from which temperature and RH measuring circuits were connected via a cable to the computer. The 9 month monitoring period incorporated the range in seasons from winter through to autumn. Between December and February the RH at the back of the painting was found to be lower than that at the front. In March and April the reverse was true. Additionally, there were large spikes in the data in some of the months for both RH and temperature, probably caused by direct sunlight falling on the sensors. At the second site monitoring was performed for a shorter period, from December 1997 to early January 1998. It served, however, to show that abrupt changes can occur in the microclimate surrounding the painting. These fluctuations can with time lead to alterations to the paint surface and result eventually in cracking and damage to the art work.  相似文献   
47.
The synthetic chemical, 1,4‐dioxane, is classified by the U.S. Environmental Protection Agency (EPA) as a probable human carcinogen. Between 2013 and 2015, the EPA detected 1,4‐dioxane in public drinking water supplies in 45 states at concentrations up to 33 µg/L and in groundwater from releases at hazardous waste sites across the United States. Although a Federal maximum contaminant level drinking water standard has not yet been proposed, state‐specific standards and criteria are as low as 0.3 µg/L. 1,4‐Dioxane is a recalcitrant chemical in that applications of conventional treatment technologies have had limited success in reducing concentrations in water to meet current and proposed health‐protective levels. Although mainly used as a stabilizer for the solvent 1,1,1‐trichloroethane, it has been used in other industrial processes and has been detected in a variety of consumer products, such as foods, pharmaceuticals, cosmetics, and detergents. The high aqueous solubility of 1,4‐dioxane coupled with limited solubility of chlorinated solvents typically found in conjunction with 1,4‐dioxane contamination is the primary reason for its treatment challenges. In the last several years, an alternative, cost‐effective technology has been developed that has demonstrated treatment to levels significantly lower than the Federal and state‐specific goals. This article provides a Federal and state‐by‐state summary of 1,4‐dioxane‐specific drinking water and groundwater concentration criteria and qualitative comparison of the effectiveness of conventional treatment technologies compared to the effectiveness of an alternative treatment technology. A case study is also provided to present details regarding the application of an alternative treatment technology at an active groundwater remediation site in California.  相似文献   
48.
Summary The mating system of the Swallow-tailed Manakin (Chiroxiphia caudata) is a type of non-resource based polygyny in which males aggregate at traditional sites or leks to perform cooperative displays. Each lek and all its contained courts are used communally by a group of 4–6 males. Within the group a linear dominance hierarchy exists. Position in the hierarchy persists within and between years and at all courts and is inherited in linear sequence. The dominant male of the group behaves as a sentinel calling repeatedly from a high perch in an attempt to attract females to a court.When a female arrives, two or three males engage in a cooperative precopulatory dance, the Jump Display. This is followed by a Solo Precopulatory Display performed by a single male who, if successful, will copulate with the female. With rare exception, the dominant male performs all Solo Displays and all copulations.Display sequences that include both a Jump Display and Solo Precopulatory Display are more likely to lead to copulation than those consisting of only one part. Thus, the subordinates who help the dominant perform the dance are expending energy that increases his fitness without receiving any immediate benefit themselves. Several factors that may have contributed to the evolution of the mating system and cooperative displays of this species are considered.  相似文献   
49.
Minor and trace elements in the shell of Patella aspera (Röding 1798)   总被引:1,自引:0,他引:1  
Specimens of the limpet Patella aspera were collected from a clean, coastal marine site and a contaminated estuary on the south coast of Portugal. The shells were analysed individually for their minor (Mg, Sr) and trace element (Fe, Mn, Zn) content. Mean concentrations of these elements in the shell of P. aspera were 4651, 1318, 35.8, 29.9 and 5.5 microg g(-1), respectively. The elemental concentrations exhibited both a marked intra- and inter-population variability. Despite the variability within individual populations, significant differences in the trace element composition were apparent between the shells taken from the two sites. Small shells (< 2 g) provided the best resolution between sites for both manganese and iron. Differences in zinc were best resolved for larger shells. The shell of P. aspera has an extraordinarily high magnesium concentration, which is insensitive to gross salinity differences, and a trace metal assemblage that can be interpreted in terms of environmental exposure. On these grounds, it is recommended that the shell of P. aspera is a tissue for potential use in environmental trace metal monitoring.  相似文献   
50.
Environmental Science and Pollution Research - Manganese (Mn) is an essential element that, in excess, seems to be involved in the development of different neurodegenerative conditions....  相似文献   
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