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121.
Betrieblicher Umweltschutz gilt heute als unverzichtbarer Bestandteil moderner Unternehmensführung. Im Gegensatz zu „end of pipe”-Technologien als kostentreibende Ma?nahmen wird der integrierte Umweltschutz, von der Technologie über das Managementsystem bis hin zum Mitarbeiter zunehmend zu einem betriebswirtschaftlichen Erfolgsfaktor. Notwendige Voraussetzung für diesen Erfolg ist ein gut strukturiertes Umweltmanagementsystem (UM-System). Das beschriebene UM-System orientiert sich an der EG-Verordnung über die „Freiwillige Beteiligung gewerblicher Unternehmen an einem Gemeinschaftssystem für das Umweltmanagement und die Umweltbetriebsprüfung”. Da sowohl auf nationaler als auch auf internationaler Ebene sehr intensiv an einer Normierung von Umweltmanagementsystemen gearbeitet wird, bringt diese Arbeit einen Vergleich zum ISO-Entwurf für UM-Systeme.  相似文献   
122.
The results of a degradation study of the (fluoro)quinolone antibiotics ciprofloxacin and oxolinic acid in river water samples are presented in this paper. The decomposition of these compounds at ambient temperature was monitored during five months by HPLC-UV, and two consecutive degradation processes (photo- and bio/chemical-degradation) were observed in both cases although with different degradation rates. Ciprofloxacin was completely degraded after 3 months whereas 80% of oxolinic acid remained unaltered after five months of storage. The analysis of the degradation compounds formed was carried out using MS and tandem MS-MS, allowing the identification of four new ciprofloxacin transformation products not previously described in the literature. Possible degradation pathways for this antibiotic in river water are proposed.  相似文献   
123.
Nonindigenous invasive plants pose a major threat to natural communities worldwide. Biological control of weeds via selected introduction of their natural enemies can affect control over large spatial areas but also risk nontarget effects. To maximize effectiveness while minimizing risk, weed biocontrol programs should introduce the minimum number of host-specific natural enemies necessary to control an invasive nonindigenous plant. We used elasticity analysis of a matrix model to help inform biocontrol agent selection for garlic mustard (Alliaria petiolata (M. Bieb.) Cavara and Grande). The Eurasian biennial A. petiolata is considered one of the most problematic invaders of temperate forests in North America. Four weevil species in the genus Ceutorhynchus (Coleoptera: Curculionidae) are currently considered potential biocontrol agents. These species attack rosettes (C. scrobicollis), stems (C. roberti, C. alliariae), and seeds (C. constrictus) of A. petiolata. Elasticity analyses using A. petiolata demographic parameters from North America indicated that changes in the rosette-to-flowering-plant transition and changes in fecundity consistently had the greatest impact on population growth rate. These results suggest that attack by the rosette-feeder C. scrobicollis, which reduces overwintering survival, and seed or stem feeders that reduce seed output should be particularly effective. Model outcomes differed greatly as A. petiolata demographic parameters were varied within ranges observed in North America, indicating that successful control of A. petiolata populations may occur under some, but not all, conditions. Using these a priori analyses we predict: (1) rosette mortality and reduction of seed output will be the most important factors determining A. petiolata demography; (2) the root-crown feeder C. scrobicollis will have the most significant impact on A. petiolata demography; (3) releases of single control agents are unlikely to control A. petiolata across its full range of demographic variability; (4) combinations of agents that simultaneously reduce rosette survival and seed production will be required to suppress the most vigorous A. petiolata populations. These predictions can be tested using established long-term monitoring sites coupled with a designed release program. If demographic models can successfully predict biocontrol agent impact on invasive plant populations, a continued dialogue and collaboration between empirical and theoretical approaches may be the key to the development of successful biocontrol tactics for plant invaders in the future.  相似文献   
124.
Alpha-fetoprotein (AFP), unconjugated oestriol (UE3), intact human chorionic gonado-trophin (intHCG), and the free β subunit of chorionic gonadotrophin (FβHCG) were investigated in a series of 21 chromosomally abnormal and 14 open neural tube defect pregnancies ascertained from a series of 14 000 prospectively collected maternal serum samples at 6–14 weeks' gestation. In 16 cases of Down's syndrome, significant reductions were found for AFP (0.65 multiples of the normal median) and UE3 (0.67 MOM). IntHCG levels were unaltered (0.97 MOM) but a significant increase was found for FβHCG (1.96 MOM). Significant correlations were found for AFP and UE3 in the controls and for int HCG and FβHCG in both the control and the Down's syndrome pregnancies. In a group of five trisomy 18 pregnancies, median MOMs were for AFP 0. 71 , for UE3 0. 34 , for intHCG 0. 27 , and for FβHCG 0.15. None of 13 pregnancies with open neural tube defects at 8-13 weeks gestation had elevated maternal serum AFP levels, whereas matched second-trimester samples from the same pregnancies at 16-18 weeks gestation all had significantly elevated AFP levels. Thus, biochemical screening for chromosome abnormalities may be practicable in the first trimester using free β human chorionic gonadotrophin in combination with AFP and maternal age. However, a separate screening protocol using AFP at 15-18 weeks gestation would still be required for effective detection of neural tube defects.  相似文献   
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Conflict management influences individual wellbeing, group performance and organizational effectiveness. This research examined the psychometric qualities of two versions of the newly developed test for conflict handling. The lean version (Study 1 and 2) included problem solving, forcing, yielding and avoiding as distinct conflict management strategies, and the expanded version (Study 3) also included compromising. A negotiation study (Study 1) showed substantial convergence between self‐reports, opponent‐reports and observer rated behavior for problem solving, forcing and yielding, but not for avoiding. In Study 2 and Study 3 the psychometric properties were examined of the lean and the expanded version, respectively. Confirmatory factor analyses revealed good to excellent psychometric qualities of both versions of the scale. We conclude that the scale is a parsimonious, flexible and valid instrument to assess conflict management strategies at work. Copyright © 2001 John Wiley & Sons, Ltd.  相似文献   
128.
The success that the putative alien species Oculina patagonica is able to survive under different environmental conditions may be benefiting its establishment and spreading along the Mediterranean Basin. Our objectives were to determine the response of this species, in terms of growth and bleaching, under different environmental conditions. Field data on colony growth and bleaching were obtained for a period of 18 months (from June 2010 to December 2011), in the Alicante Harbour (38°20′11″N, 00°29′11″W) and the Marine Protected Area of Tabarca (38°09′59″N, 00°28′56″W). Additionally, data on sedimentation rates, chlorophyll a concentration and organic matter were also collected. Moreover, the role of light over growth and bleaching of the coral was also studied with a field experiment. Our results showed that growth rates were similar among localities (eutrophic and oligotrophic environments), decreasing with increasing perimeter of the colony. Growth rates were at a minimum during cold months (13 °C) and enhanced during warm months until a threshold temperature; thereafter, bleaching was observed (>28 °C), being adverse for coral growth. In addition, light attenuation could act such as local stress, increasing the coral bleaching with the increase in seawater temperature. Our findings confirmed that O. patagonica has a broad tolerance to seawater temperature, irradiance and trophic water conditions, in addition to its ability to thrive through bleaching events, mainly in eutrophic environments, probably related to food availability.  相似文献   
129.
It has been suggested that pedestrians listening to personal music devices (PMD) are more likely to be involved in accidents than those not listening to PMDs. Though it has been demonstrated that pedestrians on cell phones exhibit less cautionary behaviour when street crossing ( [Hatfield and Murphy, 2007], [Nasar et al., 2008] and [Stavrinos et al., 2009]), little research has been conducted with PMD users. In the present study, cautionary behaviour (e.g., looking before crossing a road) was observed and recorded for pedestrians with or without PMDs. Amongst males, pedestrians listening to PMDs displayed more looking behaviour than those not listening to PMDs. Females showed no differences between the two conditions. Thus, unlike cell phones, PMDs do not decrease the cautionary behaviour of pedestrians. This suggests that cell phones and PMDs are two different types of distractions, and this needs to be taken into account when developing methods to prevent pedestrian accidents in the future.  相似文献   
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