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101.
通过改常压洗网、毡为高压冲洗网毡,可节水70%左右,然后废水进旋转筛可去除SS及非可溶性COD;再调节pH值,加碱式氯化铝及PAM絮凝,进一步去除COD、SS. 相似文献
102.
The EU is presently in a transition phase from environmental policy-making by law towards other governance approaches based upon networking, voluntary commitments, benchmarking and other forms of “soft law”. Those new governance approaches often claim to lead to “better regulation”, while adopting a more consensus-oriented and participatory style, taking economic aspects more seriously into account, allowing for more flexibility and autonomy for the private sector and Member States alike, mobilising a broader knowledge base or adopting more integrated and holistic approaches than previous sectoralised and compartmentalised policies.While the limitations of traditional regulatory approaches are widely accepted and cited, it is far from evident, that “new modes of governance” have greater capacity to solve problems than the old ones. There is an argument, that “better regulation” might by synonymous to a withdrawal and weakening of the regulatory state and hence effectively of the aspirations and objectives of environmental policies.An interesting case for an approach, combining the strengths of the old and the new approaches is the ongoing reform of chemicals policies. While some observers claim, that the proposed directive, “REACH” might belong to the outdated category of overcomplex and bureaucratic regulation, a closer look shows that there are many new forms of governance in REACH. This mixture or old and new may open a more realistic and promising perspective on the reform of European policy-making.In our paper we assess the effects and the interplay of the combination of different modes of governance using the example of REACH. We are particularly concerned with the question in how far the representation of interests may change when new modes of governance are introduced. 相似文献
103.
Gardar Johannesson Noel Cressie Hsin-Cheng Huang 《Environmental and Ecological Statistics》2007,14(1):5-25
Data from remote-sensing platforms play an important role in monitoring environmental processes, such as the distribution
of stratospheric ozone. Remote-sense data are typically spatial, temporal, and massive. Existing prediction methods such as
kriging are computationally infeasible. The multi-resolution spatial model (MRSM) captures nonstationary spatial dependence
and produces fast optimal estimates using a change-of-resolution Kalman filter. However, past data can provide valuable information
about the current status of the process being investigated. In this article, we incorporate the temporal dependence into the
process by developing a dynamic MRSM. An application of the dynamic MRSM to a month of daily total column ozone data is presented,
and on a given day the results of posterior inference are compared to those for the spatial-only MRSM. It is apparent that
there are advantages to using the dynamic MRSM in regions where data are missing, such as when a whole swath of satellite
data is missing. 相似文献
104.
Roman?Martin?WittigEmail author Christophe?Boesch 《Behavioral ecology and sociobiology》2003,54(5):491-504
>We examined the "decision-making" process of aggressive interactions within a community of wild chimpanzees (Pan troglodytes verus) in the Taï National Park, Côte d'Ivoire (West Africa). Costs and benefits were investigated for 876 dyadic aggressive interactions among 18 adults (including 4 independent adolescents) of either sex. An extended version of the Relational Model was developed to describe the dynamics of the "decision-making" process in Taï chimpanzees, which suggests that the net benefit determines the occurrence of conflicts. Both sexes fought more frequently for the resources that were most important to them, food for females and social contexts for males. Individuals used two different strategies according to their likelihood of winning the aggressive interaction, determined by the dominance relationship of the conflict partners. Dominant initiators had longer and more intense aggressive interactions, but they limited their social disadvantages by fighting non-cooperative partners. Subordinate initiators had shorter and less intense aggressive interactions, but risked more social costs, which they could reduce afterwards by reconciliation. Both strategies included a positive overall net benefit. The extended Relational Model fits the complexity of wild chimpanzee conflicts and allows for more flexibility in the "decision-making" compared to the original version.Communicated by E. Sterck 相似文献
105.
The Extended Kalman Filter (EKF) as a tool for the assimilation of high frequency water quality data
The Extended Kalman Filter (EKF) was applied to the analysis of high frequency field measurements of dissolved oxygen (DO), water temperature, salinity, collected by multiparametric sensors in the lagoon of Venice. This paper focuses on the practical aspects of the implementation of the EKF as a data assimilation technique and does not deal with the problems associated with the identification of the model. In this regard, the EKF has proved to be a useful tool for the updating of the estimates of the parameters of a simple DO-chlorophyll model, which can be used for linking the high frequency data to meteorological forcings, such as solar radiation and wind, and to other low frequency measurements of water quality parameters, such as the concentrations of Chlorophyll a and nutrients. The model can subsequently be used as a tool for checking the consistency of all this data, and may also be employed for controlling the quality of the data collected by the multiparametric sensors. 相似文献
106.
KALMAN FILTER ESTIMATION AND PREDICTION OF DAILY STREAM FLOWS: II. APPLICATION TO THE POTOMAC RIVER1
Results are reported from an application of the state space formulation and the Kalman filter to real-time forecasting of daily river flows. It is shown that the application of filtering techniques improves the overall forecasting performance of the model. As is true for most hydrologic systems, the model is not completely known. Therefore, the procedures pertaining to on-line parameter and noise statistics estimation, as presented in the first paper, are implemented. The example in this paper shows that these techniques also perform satisfactorily when applied to a real-world situation. 相似文献
107.
Zusammenfassung Durch r?umlich integrale Bestimmung der Schadstofffrachten [1] und zeitlich integrales Monitoring mit Schadstoff-Dosimetern
[1] l?sst sich Topographie und Bewegung von Schadstofffahnen im Grundwasser bestimmen. Konventionelle Methoden der Entnahme
und Untersuchung von Wasserproben sind ungeeignet zur Erfüllung dieser Anforderungen. Sorptionsaktive Passivsammler, die für
entsprechende Untersuchungen in der Gasphase konzipiert sind, eignen sich nicht zur Aquiferuntersuchung.
Die Passivsammler zur Untersuchung im ungest?rten Aquifer sind zentraler Bestandteil eines Systems von Probenahme- und Messsonden,
das die Autoren für das Monitoring chemischer und hydraulischer Wasser-Parameter entwickelt haben.
Mit den Passivsammlern lassen sich die relativen Schadstofffrachten in beliebig enger tiefenorientierter Anordnung der Messpunkte
und auch zeitlich integriert zur Gewinnung von vertikalen relativen Schadstofffracht-Profilen ermitteln. Organische und anorganische
relative Schadstofffrachten k?nnen damit bestimmt werden.
Die gaiasafe-Passivsammler sind einfach handhabbar und lassen sich nach standardisierten chemischen Analysenmethoden auswerten.
Damit erfüllen sie eine Reihe wesentlicher Anforderungen an das zielführende Monitoring von Schadstofffahnen. Die Passivsammler
sind auch geeignet für die In-situ-Untersuchung von ruhigen und bewegten Gew?ssern auch in gro?er Tiefe z.B. Abw?sserkan?le,
Kl?ranlagen, Flüsse und Meere und insbesondere zum Nachweis von Kontaminanten und Spurenstoffen in Wasserproben.
Online First: 10. 01. 2001 相似文献
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110.
Parameters in process-based terrestrial ecosystem models are often nonlinearly related to the water flux to the atmosphere, and they also change temporally and spatially. Therefore, for estimating soil moisture, process-based terrestrial ecosystem models inevitably need to specify spatially and temporally variant model parameters. This study presents a two-stage data assimilation scheme (TSDA) to spatially and temporally optimize some key parameters of an ecosystem model which are closely related to soil moisture. At the first stage, a simplified ecosystem model, namely the Boreal Ecosystem Productivity Simulator (BEPS), is used to obtain the prior estimation of daily soil moisture. After the spatial distribution of 0–10 cm surface soil moisture is derived from remote sensing, an Ensemble Kalman Filter is used to minimize the difference between the remote sensing model results, through optimizing some model parameters spatially. At the second stage, BEPS is reinitialized using the optimized parameters to provide the updated model predictions of daily soil moisture. TSDA has been applied to an arid and semi-arid area of northwest China, and the performance of the model for estimating daily 0–10 cm soil moisture after parameter optimization was validated using field measurements. Results indicate that the TSDA developed in this study is robust and efficient in both temporal and spatial model parameter optimization. After performing the optimization, the correlation (r2) between model-predicted 0–10 cm soil moisture and field measurement increased from 0.66 to 0.75. It is demonstrated that spatial and temporal optimization of ecosystem model parameters can not only improve the model prediction of daily soil moisture but also help to understand the spatial and temporal variation of some key parameters in an ecosystem model and the corresponding ecological mechanisms controlling the variation. 相似文献