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111.
The End-of-life Vehicles Recycling Act went into effect on January 1, 2005, in Japan and requires the proper treatment of airbags, chlorofluorocarbons (CFCs), and automobile shredder residue (ASR). The need for optimal treatment and recycling of ASR, in particular, has been increasing year after year because ASR is regarded as being difficult to treat. Dioxin-related compounds, brominated flame retardants (BFRs), heavy metals, chlorine and organotin compounds are all present in high concentrations in ASR. The authors conducted ASR melting treatment tests using a 10-tons/day-scale direct melting system (DMS), which employs shaft-type gasification and melting technology. The results obtained showed that dioxin-related compounds and BFRs were decomposed by this melting treatment. The high-temperature reducing atmosphere in the melting furnace moved volatile heavy metals such as lead and zinc into the fly ash where they were distributed at a rate of more than 90% of the input amount. This treatment was also found to be effective in the decomposition of organotin, with a rate of decomposition higher than 99.996% of the input amount. Via the recovery of heavy metals concentrated in the fly ash, all the products discharged from this treatment system were utilized effectively for the complete realization of an ASR recycling system that requires no final disposal sites.  相似文献   
112.
An intercalibration study on organobromine compounds has been conducted to evaluate the accuracy and reliability in the analysis of brominated flame retardants (BFRs) such as polybrominated diphenyl ethers (PBDEs) and their related compounds like polybrominated and monobromo-polychlorinated dibenzodioxins and -furans (PBDDs/DFs, MoBPCDDs/DFs). This paper reports the results for these compounds in 'Mixed Standard Solutions' and 'Air-Dried Sediment'. The relative standard deviations (RSDs) for PBDEs, PBDDs/DFs and MoBPCDDs/DFs in mixed standard solutions ranged from 9% to 24%, 4% to 20% and 8% to 27%, respectively. The results of this study are better than those reported in earlier international interlaboratory studies due to general improvement in analytical methods and an increasing number of available authentic standards, particularly for PBDEs. In the analysis for higher brominated compounds such as octabromodibenzodioxin, the participants were advised to optimize the calibration curves befitting the range of concentrations found in samples because variation of relative response factors was noted. The results for 'Air-Dried Sediment' were also reasonable with RSDs from 10% to 38% for PBDEs, 8% to 38% for PBDDs/DFs and 17% to 36% for MoBPCDDs/DFs. In the sediment sample, possible errors in the sample pretreatment and/or interference by other compounds/impurities were indicated. The concentrations of pentabromodiphenylether, BDE100, varied more than the other PBDE isomers due to its poor separation in some chromatographic conditions. In addition, interference by PBDEs was observed in the analysis for PBDFs. Potential degradation/secondary formulation of PBDEs and PBDFs during the Soxhlet extraction were suggested when copper powder was added into the sediment samples. Inspite of these observations, the results in this study are better than those reported in other interlaboratory studies due to the advice given to participants for improving the results. Compared with the results for PCDDs/DFs (5-23% RSDs) and Co-PCBs (6-24% RSDs), the RSDs for most of the organobromine compounds were high, indicating an immature QA/QC approach for the analysis of PBDEs and related compounds in comparison to common chlorinated dioxins.  相似文献   
113.
Congenital epulis is a benign intraoral tumor that has rarely been diagnosed prenatally. We report a fetus with congenital epulis diagnosed by three-dimensional (3-D) ultrasound and fetal magnetic resonance imaging (MRI) at 35 weeks' gestation. We show an image of congenital epulis using a new ultrasound technique, the 3-D multislice view, which shows images similar to CT or MRI. This is a short case report of congenital epulis diagnosed prenatally by 3-D ultrasound using multislice view and MRI. Copyright © 2006 John Wiley & Sons, Ltd.  相似文献   
114.
115.
The characteristics of springtime aerosols,including their optical and microphysical properties,were analyzed for the months of March to May of 2009 in Gwangju(35.23°N,126.84°E),Korea.A high Light Detection and Ranging(LIDAR)-derived aerosol depolarization ratio(δ) of 0.25 ± 0.04 was determined on dust particles during the observation period.The?ngstr?m exponent values of the 440–870 nm wavelength pair(?_(440–870)) and single-scattering albedo at 675 nm(Ω_(675)) measured by a CIMEL sun/sky radiometer were 0.77 ± 0.19 and 0.95 ±0.01,respectively.The elevated dust layers reached a maximum elevation of 4 km above sea level.Anthropogenic/smoke particles that originated from highly populated/industrialized regions could be distinguished by their relatively smaller particle size(?_(440–870) ranged between1.33 and 1.36) and higher light-absorbing(Ω_(675) of 0.92 ± 0.01) characteristics.These aerosols are mostly distributed at altitudes 1.2 km.The root-mean-square deviation(RMSD) between the aerosol optical depth(AOD,τ) derived from LIDAR_((τ_(LIDAR))) and from the CIMEL sun/sky radiometer_((τ_(CIMEL))) varied with respect to the surface PM10 concentration.The RMSD between τ_(LIDAR) and τ_(CIMEL) was as low as 13% under lower PM_(10) concentration levels( 100 μg/m~3).In contrast,the RMSD between τ_(LIDAR) and τ_(CIMEL) increased three times(~31%) under high surface PM_(10) concentration levels(100 μg/m~3).These results suggest that the accuracy of τ_(LIDAR) is influenced by specific atmospheric conditions,regardless of its uncertainty.  相似文献   
116.
Noroviruses are major causative pathogen of nonbacterial acute gastroenteritis worldwide. Of the seven genogroups of noroviruses suggested recently, genogroup II genotype 4 (GII.4) had been the most common genotype identified in hospitalized patients in the last few decades. However, since the latter half of 2014, new variants of GII.17 have been reported as the main causes of outbreaks over GII.4 in East Asia and have also occurred in America and Europe. In this study, we monitored norovirus GII in coastal streams at South Gyeongsang province and South Jeolla province of South Korea from March 2015 to May 2016. Norovirus GII.17 capsid sequences were predominantly detected until September 2015 in water samples. However, we found that the number of positive cases of the norovirus GII.4 Sydney 2012 capsid sequence has been increasing since December 2015, overtaking that of GII.17 in 2016. The RdRp genotype of this predominant GII.4 variant in 2016 was identified as GII.P16. The emergence and predominance of the GII.4 pandemic capsid sequence harboring a different RdRp genotype suggested the potential for a future pandemic.  相似文献   
117.
An alkaline comet assay and a micronucleus test were carried out on erythrocytes of the European chub, Squalius cephalus L., collected in spring and autumn in 2005 and 2006 at three sampling sites in River Sava, near Zagreb, Croatia. The results of comet assay showed the lowest genotoxic influence at the least polluted site, while higher DNA damage was observed at the polluted sites. Although the basal levels of DNA damage were elevated, a clear gradation of DNA damage was found due to pollution intensity in all sampling periods. The lowest cytogenetic damage as revealed by the micronucleus test (MNT) was observed as well at the least polluted site. High variations in MN frequency were observed between sampling periods, although the number of micronucleated erythrocytes was consistently the highest one at the polluted site. The comet assay as a biomarker of genotoxic effect exhibited higher sensitivity in discriminating the genotoxic capacity of studied polluted sites while the MNT was less sensitive. However, both tests should be used together in biomonitoring studies because they can reveal different aspects of DNA damage; comet assay, the early event of genotoxic exposure, and MNT, its final result as a mutagenic potential.  相似文献   
118.
This study measures the effect of emissions from an airport on the air quality of surrounding neighborhoods. The ambient concentrations of benzene, toluene, ethylbenzene, and o-, m-, and p-xylene (BTEX) were measured using passive samplers at 15 households located close to the airport (indoor, outdoor, and personal), at the end of airport runways and an out-of-neighborhood location. Measurements occurred over a 48-h period during summer 2006 and winter 2006?C2007. The average concentrations were 0.84, 3.21, 0.30, 0.99, and 0.34 ??g/m3 at the airport runways and 0.84, 3.76, 0.39, 1.22, and 0.39 ??g/m3 in the neighborhood for benzene, toluene, ethylbenzene, m-, p-, and o-xylene. The average neighborhood concentrations were not significantly different to those measured at the airport runways and were higher than the out-of-neighborhood location (0.48, 1.09, 0.15, 0.78, and 0.43 ??g/m3, each BTEX). B/T ratios were used as a tracer for emission sources and the average B/T ratio at the airport and outdoors were 0.20 and 0.23 for the summer and 0.40 and 0.42 for the winter, suggesting that both areas are affected by the same emission source. Personal exposure was closely related to levels in the indoor environment where subjects spent most of their time. Indoor/outdoor (I/O) ratios for BTEX ranged from 1.13 to 2.60 and 1.41 to 3.02 for summer and winter. The seasonal differences in I/O ratios reflected residential ventilation patterns, resulting in increased indoor concentrations of volatile organic compounds during winter.  相似文献   
119.
Environmental Science and Pollution Research - This study examined differences in the adsorption isotherms, kinetic equations, and thermodynamics of Sr2+ by biochar from spent coffee grounds (SCG)...  相似文献   
120.
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