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121.
Allan Correy 《Journal of Environmental Planning and Management》1977,20(2):14-27
In 1788 Humphrey Repton made his important decision to carry on in the Brown tradition, and the well established Eighteenth Century English Landscape School continued in Europe for another thirty years. (Stroud: 1962) Also, in that same year, the British Government founded its first penal colony in New Holland, and as those unfortunate convicts and soldiers began clearing the virgin bush from the shores of Sydney Cove, so began the landscape destruction which has haunted Australia to the present time. 相似文献
122.
Seat belt laws by themselves led to increased belt use in the United States and Canada, but initial effects were limited. Canadian provincial officials launched highly publicized enforcement campaigns in the early 1980s that resulted in substantially increased belt use. Canadian-style enforcement programs subsequently were adopted in the United States, and the use of such programs has grown in recent years. Lessons from these efforts include the importance of police leadership, focused publicity about enforcement, and sustained rather than single-shot efforts. What is needed in the United States to achieve a national belt use rate of 90% or greater is widespread, methodical, and sustained application of enforcement programs augmented by creative publicity. Enhanced penalties-in particular drivers license points-likely will be needed to reach hard-core nonusers. 相似文献
123.
More than 1.5 million traffic crashes involving deer, producing at least $1.1 billion in vehicle damage and about 150 fatalities, are estimated to occur annually in the United States. Deer-related crashes are increasing as both deer populations and vehicular travel increase. Many methods have been used in attempts to reduce deer crashes, often with little scientific foundation and limited evaluation. This article summarizes the methods and reviews the evidence of their effectiveness and the situations in which each may be useful. The only widely accepted method with solid evidence of effectiveness is well-designed and maintained fencing, combined with underpasses or overpasses as appropriate. Herd reduction is controversial but can be effective. Deer whistles appear useless. Roadside reflectors appear to have little long-term effect, although additional well-designed evaluations are needed before firm conclusions can be drawn. Both temporary passive signs and active signs appear promising in specific situations, but considerable research is required to evaluate long-term driver response and to improve and test deer detection technology for active signs. Other methods using advanced technology require substantial additional research and evaluation. 相似文献
124.
Habitat Assessment of Non-Wadeable Rivers in Michigan 总被引:1,自引:0,他引:1
Habitat evaluation of wadeable streams based on accepted protocols provides a rapid and widely used adjunct to biological
assessment. However, little effort has been devoted to habitat evaluation in non-wadeable rivers, where it is likely that
protocols will differ and field logistics will be more challenging. We developed and tested a non-wadeable habitat index (NWHI)
for rivers of Michigan, where non-wadeable rivers were defined as those of order ≥5, drainage area ≥1600 km2, mainstem lengths ≥100 km, and mean annual discharge ≥15 m3/s. This identified 22 candidate rivers that ranged in length from 103 to 825 km and in drainage area from 1620 to 16,860
km2. We measured 171 individual habitat variables over 2-km reaches at 35 locations on 14 rivers during 2000–2002, where mean
wetted width was found to range from 32 to 185 m and mean thalweg depth from 0.8 to 8.3 m. We used correlation and principal
components analysis to reduce the number of variables, and examined the spatial pattern of retained variables to exclude any
that appeared to reflect spatial location rather than reach condition, resulting in 12 variables to be considered in the habitat
index. The proposed NWHI included seven variables: riparian width, large woody debris, aquatic vegetation, bottom deposition,
bank stability, thalweg substrate, and off-channel habitat. These variables were included because of their statistical association
with independently derived measures of human disturbance in the riparian zone and the catchment, and because they are considered
important in other habitat protocols or to the ecology of large rivers. Five variables were excluded because they were primarily
related to river size rather than anthropogenic disturbance. This index correlated strongly with indices of disturbance based
on the riparian (adjusted R2 = 0.62) and the catchment (adjusted R2 = 0.50), and distinguished the 35 river reaches into the categories of poor (2), fair (19), good (13), and excellent (1).
Habitat variables retained in the NWHI differ from several used in wadeable streams, and place greater emphasis on known characteristic
features of larger rivers. 相似文献
125.
Problem: Motor-vehicle crash rate comparisons by age and gender usually are based on the extent to which drivers in a particular age/gender category are themselves injured or involved in crashes (e.g., the number of 20-year-old females in crashes). Basing comparisons instead on the extent to which drivers in various age/gender groups are responsible for deaths (including themselves) in their crashes is more revealing of their overall contribution to the problem. Methods: Data from the Fatality Analysis Reporting System (FARS, 1996–2000) were used in the analysis, which was based on crashes that involved one or two vehicles only. Drivers in fatal single-vehicle crashes were assumed to have responsibility for the crash. In fatal two-vehicle crashes, driver operator errors reported by police were used to assign crash responsibility. Results: When all crashes were considered, both the youngest and oldest drivers were most likely to be responsible for deaths in their crashes. In two-vehicle crashes, the oldest drivers were more likely than young drivers to be responsible. Young males were more likely than young females to be responsible for crash deaths, whereas females in their 50s and older were more likely than same-age males to be responsible. In terms of responsibility for deaths per licensed driver, young drivers, especially males, had the highest rates because of their high involvement rates and high responsibility rates. The majority of deaths for which young drivers were responsible occurred to people other than themselves, especially passengers in their vehicles, whereas the bulk of the deaths for which older drivers were responsible were their own. Discussion: The results highlight the contribution of young drivers to the motor-vehicle crash problem, the need for measures such as passenger restrictions in graduated licensing systems, and the need for vehicle modifications to better protect older occupants. 相似文献
126.
Allan Curtis Bruce Shindler Angela Wright 《Journal of the American Water Resources Association》2002,38(5):1207-1216
ABSTRACT: In the last decade, watershed groups (WG) established through government initiatives have become an important part of the natural resource management landscape in developed economies. In this paper, the authors reflect upon their research and experience with Landcare in Victoria, and to a lesser extent with Watershed Councils in Oregon, to identify the principles that appear fundamental to sustaining effective WG. In the first instance, these groups must be established at a local scale using social as well as biophysical boundaries. It is also critical that WG are embedded within a supportive institutional framework that identifies realistic roles for private landowners, local organizations such as WG, and regional planning bodies. Without broad stakeholder representation, the perceived benefits of participation are quickly forfeited. It is simply unrealistic to expect an effective network of WG to be sustained without substantial investment by government to provide for program management, group coordination, and cost sharing for on‐ground work. There must also be the commitment and skills within a program to establish processes that build trust and competency amongst citizens and agencies. These principles should also provide a foundation for the critical evaluation of WG programs. 相似文献
127.
Allan G. Sangster Lewis Ling Frédéric Gérard Martin J. Hodson 《Water, Air, & Soil Pollution: Focus》2007,7(1-3):143-149
Douglas fir [Pseudotsuga menziesii (Mirb.) Franco] shoots from mature trees were collected from two sites of contrasting soil pH: the Glendon campus of York
University in Toronto, Canada (pH 6.7 at 40 cm) designated Can.; and Breuil Forest, Morvan, France (pH 4 to 4.5) designated
Fr.. Needles were removed from the shoots, frozen in liquid nitrogen, and kept in a cryo-biological storage system prior to
X-ray microanalysis on the cold stage (−170°C) of a cryo-SEM. Four elements detected, potassium, phosphorus, sulphur and chlorine,
were ubiquitous in the needle tissues from both sites. Manganese was infrequently found in needle tissues from the Fr. site.
Calcium was localized most heavily in the outer tangential wall of the hypodermis and also in the epidermal walls. Silicon
(Si) concentrations were higher in the Fr. site than in the Can. site. The epidermis, hypodermis and mesophyll of needles
from the Fr. site exhibited the highest Si content, with greater amounts in the tip and middle of the needle than in the base.
Aluminium was distributed fairly evenly throughout the tissues, and there were few major sites of concentration. 相似文献
128.
Kerstin Norman H?kan Alm Ewa Wigaeus Tornqvist Allan Toomingas 《International journal of occupational safety and ergonomics》2006,12(1):53-68
BACKGROUND: The purpose was to study the test-retest reliability and internal consistency of questions in a questionnaire concerning working conditions and health and the inter-rater reliability of observations and measurements according to an ergonomic checklist. METHOD: Fifty-seven operators participated in a retest questionnaire and 58 operators participated in an inter-observer test. RESULTS: The questions had fair to good or higher reliability in 142 of the total of 312. Twenty-seven of the total of 44 variables in the ergonomic checklist were classified as having fair to good or higher reliability. CONCLUSIONS: About half of the questions had fair to good or higher reliability and can be recommended for further analyses. The majority of variables in the ergonomic checklist were classified as having fair to good or higher reliability. Low reliability does not necessarily indicate that the reliability of the test, per se, is low but may signify that the conditions measured vary over time or that the answers are aggregated in one part of the scale. 相似文献
129.
OBJECTIVES: To review the research evidence concerning the effects of passengers on teenage driving and crash involvement, and to explore ways to reduce negative effects. METHODS: Review of the international literature on these topics. RESULTS: Passenger presence increases crash risk for teenage drivers, especially when the passengers are other teenagers and especially when they are male. Female passengers do not have the same effects. Teenagers are more susceptible to peer influences than adults. The combination of passenger-induced distraction and driving inexperience can disrupt driving behavior, and there is evidence that teenage driver risk taking increases in vehicles with multiple teenagers. Possible ways to reduce the resulting crash problem include altering the in-vehicle behavior of teenagers or influencing their selection of travel partners. Legal restrictions on passengers with teenage drivers have been found effective in reducing the crash problem. Parental monitoring of teenage driving behavior, and programs aimed at teenagers themselves, could be other options but their efficacy is unproven. It currently is unknown why female passengers have a different effect than males or if that might offer clues about future interventions. CONCLUSIONS: Despite passenger restrictions in the majority of states, 42% of 16- and 17-year-old drivers in fatal crashes in 2005 were transporting teenagers with no adults in the vehicle; 61% of teenage passenger deaths (1,222 in 2005) occurred in vehicles driven by other teenagers. Wider application of passenger restrictions is indicated. IMPACT ON INDUSTRY: Ways to make passenger restrictions more effective are needed, and other techniques for reducing this major problem need development and testing. 相似文献
130.
OBJECTIVE: The objective of the study was to determine which vehicle factors are significantly related to pelvic injury in side impact collisions. Identification of relevant parameters could aid in the reduction of these injuries. METHOD: Side impact crashes from the CIREN database were separated into those in which the occupant sustained a pelvic fracture and those in which no pelvic fracture occurred, although all occupants had serious injuries. A multibody MADYMO model was created of a USDOT SINCAP (U.S. Department of Transportation Side Impact New Car Assessment Program) test of a vehicle with a large center console. RESULTS: From a study of 113 side impact crashes in the ciren database, nearside occupants with pelvic fractures (n = 78) had (i) more door intrusion (mean, 37 vs. 32 cm, p = 0.02) than those who had serious injuries, but not pelvic fractures (ii) a greater likelihood that the lower border of the door intruded more than the upper part (40% vs. 18%, p < 0.025); and (iii) a greater likelihood that their vehicle had a center console (47 vs. 17%, p < 0.005). Other parameters such as occupant age, weight, gender, vehicle weight, and struck vehicle speed change were not significantly different. MADYMO modeling showed that with a center console, an initial positive pelvic acceleration occurred at about 30 msec, followed at about 45 msec by a second acceleration peak in the opposite direction. Reducing console stiffness reduced the second acceleration but not the initial peak. Allowing the seat to translate laterally when contacted by the door reduced the initial pelvic acceleration by 50% and eliminated the second acceleration peak. CONCLUSIONS: Redesigning the center console using less stiff materials and allowing some lateral translation of the seat could aid in reducing pelvic injuries in side impact collisions. 相似文献