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831.
信息家电远程控制系统及其安全 总被引:3,自引:0,他引:3
利用蓝牙技术构建信息家电网络,通过Internet或PSTN(公共交换电话网)对信息家电实现远程控制。笔者给出了基于蓝牙技术的信息家电网络的组成,设计了基于PSTN的远程控制系统。系统采用单片机控制,用户可使用固定电话或手机,根据系统提供的语音提示对其进行远程控制。输入初始密码,由双音多频收号器接收密码,并由系统进行验证,只有正确输入密码,用户才有权对系统进行操作,且可连续对信息家电系统中多个设备实施远程控制。初始密码验证通过后,用户可以根据语音提示很方便地进行密码的设置和修改。通过设置密码和蓝牙技术的安全机制,提供了信息家电网络和远程控制系统的安全保障。 相似文献
832.
Scott J. Goetz 《Journal of the American Water Resources Association》2006,42(1):133-143
Riparian buffer zone management is an area of increasing relevance as human modification of the landscape continues unabated. Land and water resource managers are continually challenged to maintain stream ecosystem integrity and water quality in the context of rapidly changing land use, which often offsets management gains. Approaches are needed not only to map vegetation cover in riparian zones, but also to monitor the changes taking place, target restoration activities, and assess the success of previous management actions. To date, these objectives have been difficult to meet using traditional techniques based on aerial photos and field visits, particularly over large areas. Recent advances in remote sensing have the potential to substantially aid buffer zone management. Very high resolution imagery is now available that allows detailed mapping and monitoring of buffer zone vegetation and provides a basis for consistent assessments using moderately high resolution remote sensing (e.g., Landsat). Laser‐based remote sensing is another advance that permits even more detailed information on buffer zone properties, such as refined topographic derivatives and multidimensional vegetation structure. These sources of image data and map information are reviewed in this paper, examples of their application to riparian buffer mapping and stream health assessment are provided, and future prospects for improved buffer monitoring are discussed. 相似文献
833.
PROBLEM: Twenty-nine percent of Americans failed to use their seat belts in 2000. Efforts to improve safety belt usage can be enhanced by identifying specific factors that motivate belt use. METHOD: Motorist survey data were used to examine the effect of Perceived Risk of being Ticketed (PRT) for a seat belt infraction on self-reported seat belt use. RESULTS: Analyses indicated that individuals and groups of individuals who have higher PRT typically report higher belt usage. Factorial analyses indicated that this perceived risk to belt use relationship holds both within groups with generally high (e.g., upper income) and generally low (e.g. young men) overall self-reported belt use. DISCUSSION: Applications of PRT to improve seat belt use are discussed. IMPACT ON INDUSTRY: Enforcement of existing laws, perhaps through selective traffic enforcement programs, and strengthening laws to create a higher perception of being ticketed by motorists should increase safety belt use thereby saving lives and reducing cost for individuals, government, and industry. 相似文献
834.
Monterde i Bort H 《Journal of Safety Research》2004,35(3):329-335
PROBLEM: This study tests whether the original factorial structure of a recklessness questionnaire can be maintained for the current Spanish population of older drivers. JUSTIFICATION: Our recent interest in dedicating special attention to senior citizen mobility (Monterde, 2001), is due to the impending increase of the aging population in Western countries; this has led us to reinitiate the psychometric study of the construct validity, revising and including older drivers in the psychometric aspects of those evaluation instruments that will then be used in the Spanish psycho-medical check of drivers and in research. METHODS: Factorial analysis was used to determine validity. RESULTS: There was an appearance of a different psychological pattern in elderly drivers, specifically, a psychological anxiety trait related to the task of driving. Furthermore, interesting data were found about the attitude of this sector toward the "traffic society" and toward some of the measures included in Spanish legislation that affect especially older drivers (such as the psycho-medical check). IMPACT ON INDUSTRY, RESEARCH AND PRACTICE: These results suggest the possible existence of some kind of "compensation phenomenon," which could have influence over the scores obtained and their interpretation. Consequently, the evaluation instruments should be tested and, if necessary, adapted or specifically created for use with this age group. 相似文献
835.
Yasushi?InoueEmail author Arata?Katayama 《Journal of Material Cycles and Waste Management》2004,6(1):48-57
An improved rescue number, RNSOIL, which is an indicator for evaluating remediation technologies for contaminated ground that is based on both the risk and the remediation cost, is proposed as a tool of risk communication. The risk posed by contaminated ground is indicated by the figure of treatment priority at time t, FTP(t), which represents the human health risk as the number of people affected by the contaminated ground at time t during the remediation process. The calculation of the value of FTP(t) is based on exposure to contaminants that have migrated through environmental media from the contaminated ground, and is estimated by using a CalTOX model and the Monte Carlo method. The integration of FTP(t) with time, which represents the cumulative number of people affected by the contaminated ground, is used to estimate the performance of individual remediation technologies in risk reduction. The figure of unprocessibility for waste (FUW), which represents difficulties in remediation, is expressed as the remediation cost. FUW is estimated by using actual costs per unit volume of remediated soil. As an overall performance value, the rescue number for each remediation technology for contaminated ground (RNSOIL) is calculated by multiplication of the integral FTP(t) by FUW. Smaller values of RNSOIL are judged to indicate a better technology. The rescue index (RI), calculated as the ratio of the reduction of the integral FTP(t) to FUW, indicates the cost-effectiveness of the remediation technologies. Successful estimation of the indices (FTP(t), integral FTP(t), FUW, RNSOIL and RI) demonstrate the usefulness of these indices in risk communication.Part of this paper was presented at 13th meeting of Japan Society of Waste Management Experts (2002) 相似文献
836.
Gorshkov V. V. Gorshkov V. G. Danilov-Danil'yan V. I. Losev K. S. Makar'eva A. M. 《Russian Journal of Ecology》2002,33(3):149-155
Closed systems are governed by the second law of thermodynamics and cannot spontaneously become more ordered. In open physical systems exposed to external energy flows, additional macroscopic degrees of freedom (memory cells) emerge, their number increasing with an increase in the flow and orderliness of the external energy. Biological systems are characterized by molecular degrees of freedom, the density of which is more than twenty orders of magnitude higher than that of macroscopic degrees of freedom in any open physical system exposed to the same external energy flow. This indicates that the self-organization of physical systems in external energy flows and the self-organization and evolution of living systems are fundamentally different. Thus, although life is an open system, the energy (food) flows that it consumes and all other external factors affecting life are so poorly ordered, compared to life itself, that they cannot increase the degree of order in the latter. Therefore, living systems obey an analogue of the second law of thermodynamics: within periods of time considerably shorter than the duration of evolutionary changes, living systems can only lose the accumulated information (i.e., the entropy can only increase), even if the systems consume external energy–food flows. 相似文献
837.
The state of North Carolina's Department of Environment and Natural Resources (NCDENR) conducts routine water quality monitoring
throughout the state to assess the health of aquatic systems. The current study reports the results of a retrospective (1990–2000)
ecological risk assessment of six heavy metals (arsenic, cadmium, copper, lead, mercury, and zinc) in 17 North Carolina basins
that was conducted to estimate the risk of heavy metal toxicity to freshwater organisms and assess the sufficiency of NCDENR's
monitoring data to identify water-quality-related ecological threats. Acute and chronic ecotoxicological thresholds (ETs)
were calculated for each metal based upon the 10th percentile of species sensitivity distributions and were normalized for
water hardness. Statewide probabilities (expressed as percentages) of a random sample exceeding acute or chronic ETs among
the six metals ranged from 0.01% to 12.19% and 0.76% to 21.21%, respectively, with copper having the highest and arsenic and
mercury the lowest risk. Basin-specific probabilities varied significantly depending upon water hardness and presumably watershed
development. Although the majority of specific sites where data were collected were at low risk for metal toxicity, some specific
sites had a high probability of toxic events associated with one or more metals. Analytical detection limits for metals were
frequently higher than estimated chronic ET, limiting the ability to assess the risk of chronic toxicity in soft-water basins.
Results suggest risk-based criteria may be useful for assessing and validating the sufficiency of monitoring programs and
prioritizing management goals. 相似文献
838.
Presently in Australia there are no mandatory drinking water standards. Here we argue that the risk associated with drinking
water in Australia is of a dimension discernible to warrant mandatory regulations. The catchments that supply the major metropolitan
areas of Sydney and Adelaide, and the groundwater for the city of Perth have been seriously compromised by the encroachment
of development and activities. Melbourne in the past has generally relied on a closed catchment reservoir system; however,
population growth in the near future will sequester the full online operation of additional reservoirs, which have multiple
land use catchments. In addition to the current landscape circumstances, the management of a water system in itself proposes
significant issues of risk. Two critical assumptions that are unique to a mass medium substance like water and dramatically
alter the appraisal of risk are: (1) very large numbers of people are potentially exposed, and (2) small changes in contaminant
levels may have adverse population outcomes. It is also known that water reticulation systems frequently suffer from contamination
problems caused solely by the distribution system, and optimal management of these facilities would best be served by statutory
protected transparency and dedicated water quality programs. In 1979, an Australian parliamentary committee stated that an
“uncontaminated water supply is” a “basic requirement for the obtainment of good health”; however, recent surveys of Australian
water systems show many are not meeting basic water quality criteria, and many communities are not receiving regular monitoring
or testing as required by government authorized Australian drinking water guidelines. Exacerbating this situation is the lack
of reporting and statutory endorsed standardized procedures to ensure information is properly and promptly recorded and that
data are centralized for maximum benefit. The evaluation of risk associated with drinking water in Australia is often hampered
by inadequate or incomplete data. Lastly, regional and rural water supplies face a vast array of contemporary problems and
experiences that include widespread usage of pesticides and agricultural chemicals. In recent years, the Darling River has
experienced the worst algal bloom known to man, and this river system not only supplies a number of regional and rural towns
with water, but eventually connects with the River Murray, which supplies the State of South Australia with approximately
50% of its water requirements. 相似文献
839.
An inventory of volatile organic compound (VOC) and nitrogen oxides (NOx) emissions is an important tool for the management of ground-level ozone pollution. This paper has two broad aims: it illustrates the potential of a geographic information system (GIS) for enhancing an existing spatially-aggregated, anthropogenic emissions inventory (EI) for Tucson, AZ, and it discusses the ozone-specific management implications of the resulting spatially-disaggregated EI. The main GIS-related methods include calculating emissions for specific features, spatially disaggregating region-wide emissions totals for area sources, and adding emissions from various point sources. In addition, temporal allocation factors enable the addition of a multi-temporal component to the inventory. The resulting inventory reveals that on-road motor vehicles account for approximately 50% of VOC and NOx emissions annually. On-road motor vehicles and residential wood combustion are the largest VOC sources in the summer and winter months, respectively. On-road motor vehicles are always the largest NOx sources. The most noticeable weekday vs. weekend VOC emissions differences are triggered by increased residential wood combustion and increased lawn and garden equipment use on weekends. Concerning the EI's uncertainties and errors, on-road mobile, construction equipment, and lawn and garden equipment are identified as sources in the most need of further investigation. Overall, the EIs spatial component increases its utility as a management tool, which might involve visualization-driven analyses and air quality modeling. 相似文献
840.
McComas KA 《Environmental management》2001,27(1):135-147
One of the more traditional ways to involve citizens in environmental management in the United States is to hold a public
meeting. Yet public meetings are also frequently criticized for stereotypical weaknesses, including a concern that citizens
who attend public meetings do not accurately represent citizens who do not attend. To examine this concern in the context
of local waste management problems, this study investigates whether citizens who attend public meetings differ from citizens
who do not attend meetings. In the spring of 1998, residents in two New York communities facing local waste management problems
received mailed questionnaires. Those surveyed included citizens who had previously attended state-sponsored public meetings
about the waste sites and citizens who lived within one mile of the respective waste sites but had not attended any meetings.
A comparison of demographic characteristics showed that, in both communities, citizens who attended meetings tended to report
higher incomes and have children living at home. In one community, previous meeting participants tended to perceive greater
risks from the waste site. In both communities, participants were less likely to consider certain sources of information about
the waste sites, including the state environmental agency, state health agency, and the industries, as credible. Regardless
of whether they had previously attended public meetings, respondents who perceived the risks as greater also perceived the
sources as less credible. The conclusions suggest some potential challenges to effective communication at public meetings,
including overcoming widespread skepticism and heightened concern among audience members. 相似文献