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61.
Plants have to counteract unavoidable stress-caused anomalies such as oxidative stress to sustain their lives and serve heterotrophic organisms including humans. Among major enzymatic antioxidants, catalase (CAT; EC 1.11.1.6) and ascorbate peroxidase (APX; EC 1.11.1.11) are representative heme enzymes meant for metabolizing stress-provoked reactive oxygen species (ROS; such as H2O2) and controlling their potential impacts on cellular metabolism and functions. CAT mainly occurs in peroxisomes and catalyzes the dismutation reaction without requiring any reductant; whereas, APX has a higher affinity for H2O2 and utilizes ascorbate (AsA) as specific electron donor for the reduction of H2O2 into H2O in organelles including chloroplasts, cytosol, mitochondria, and peroxisomes. Literature is extensive on the glutathione-associated H2O2-metabolizing systems in plants. However, discussion is meager or scattered in the literature available on the biochemical and genomic characterization as well as techniques for the assays of CAT and APX and their modulation in plants under abiotic stresses. This paper aims (a) to introduce oxidative stress-causative factors and highlights their relationship with abiotic stresses in plants; (b) to overview structure, occurrence, and significance of CAT and APX in plants; (c) to summarize the principles of current technologies used to assay CAT and APX in plants; (d) to appraise available literature on the modulation of CAT and APX in plants under major abiotic stresses; and finally, (e) to consider a brief cross-talk on the CAT and APX, and this also highlights the aspects unexplored so far.  相似文献   
62.
A majority of laboratory-driven side-impact injury assessments are conducted using postmortem human subjects (PMHS) under the pure lateral mode. Because real-world injuries occur under pure and oblique modes, this study was designed to determine chest deflections and injuries using PMHS under the latter mode. Anthropometrical data were obtained and x-rays were taken. Specimens were seated on a sled and lateral impact acceleration corresponding to a change in velocity of 24 km/h was applied such that the vector was at an angle of 20 or 30 degrees. Chestbands were fixed at the level of the axilla (upper), xyphoid process (middle), and tenth rib (lower) location. Deflection contours as a function of time at the levels of the axilla and mid-sternum, representing the thorax, and at the tenth rib level, representing the abdomen, were evaluated for peak magnitudes. All data were normalized using mass-scaling procedures. Injuries were identified following the test at autopsy. Trauma graded according to the Abbreviated Injury Score, 1990 version, indicated primarily unilateral rib fractures and soft tissue abnormalities such as lung contusion and diaphragm laceration occurred. Mean peak deflections at the upper, middle, and lower levels of the chest for the 30-degree tests were 96.2, 78.5, and 76.8 mm. For the 20-degree tests, these magnitudes were 77.5, 89.9, and 73.6 mm. Statistical analysis indicated no significant (p > 0.05) differences in peak chest deflections at all levels between the two obliquities although the metric was significantly greater in oblique than pure lateral impacts at the mid and lower thoracic levels. These response data are valuable in oblique lateral impact assessments.  相似文献   
63.

China contributes 23 % of global carbon emissions, of which 26 % originate from the household sector. Due to vast variations in both climatic conditions and the affordability and accessibility of fuels, household carbon emissions (HCEs) differ significantly across China. This study compares HCEs (per person) from urban and rural regions in northern China with their counterparts in southern China. Annual macroeconomic data for the study period 2005 to 2012 were obtained from Chinese government sources, whereas the direct HCEs for different types of fossil fuels were obtained using the IPCC reference approach, and indirect HCEs were calculated by input-output analysis. Results suggest that HCEs from urban areas are higher than those from rural areas. Regardless of the regions, there is a similarity in per person HCEs in urban areas, but the rural areas of northern China had significantly higher HCEs than those from southern China. The reasons for the similarity between urban areas and differences between rural areas and the percentage share of direct and indirect HCEs from different sources are discussed. Similarly, the reasons and solutions to why decarbonising policies are working in urban areas but not in rural areas are discussed.

  相似文献   
64.
Banana agricultural waste is one of the potential lignocellulosic substrates which are mostly un-utilized but sufficiently available in many parts of the world. In the present study, suitability of banana waste for biofuel production with respect to pretreatment and reducing sugar yield was assessed. The effectiveness of both acid and alkali pretreatments along with autoclaving, microwave heating and ultrasonication on different morphological parts of banana (BMPs) was studied. The data were statistically analyzed using ANOVA and numerical point prediction tool of MINITAB RELEASE 14. Accordingly, the optimum cumulative conditions for maximum recovery of reducing sugar through acid pretreatment are: leaf (LF) as the substrate with 25 min of reaction time and 180 °C of reaction temperature using microwave. Whereas, the optimum conditions for alkaline pretreatments are: pith (PH) as the substrate with 51 min of reaction time and 50 °C of reaction temperature using ultrasonication (US).  相似文献   
65.
Biofilm, fish, oyster, mussel, clam, surface seawater, suspended particulate matter (SPM), and sediment samples were collected from marine and/or estuarine waters of the west coast of India. These samples were analysed for butyltin derivatives such as dibutyltin (DBT) and tributyltin (TBT). The concentrations DBT plus TBT varied between 2.4 and 8.3, 163 and 363 ng/l, 5 and 2853 ng/g dry wt in the SPM, seawater and sediment samples, respectively, of the Marmugao harbour. The values of DBT plus TBT ranged between 0.60 and 29, 123 and 242 ng/l and 1.4 and 65 ng/g dry wt in SPM, water and sediment samples, respectively, collected from the Mandovi estuary. In the Dona Paula Bay the DBT plus TBT varied from 10 to 89 ng/l in surface seawater, and TBT from 10 to 513 ng/g in biofilm samples. For the coastal sediment samples the concentration of DBT plus TBT ranged between 36 and 133 ng/g dry wt of sediment. For the animal samples the DBT plus TBT ranged between 58 and 825 ng/g dry wt of the tissue. Mussel tissues contained the highest amount of DBT plus TBT (825 ng/g dry wt tissue), whereas highest TBT concentration was recorded in the oyster (732 ng/g dry wt). TBT was generally the most abundant butyltin compound in most of the samples suggesting fresh inputs and/or less degradation of TBT. A wide range of the observed butyltin concentrations suggests the presence of localized areas of contamination. Leaching of tributyltin-containing antifouling paints from the ocean going ships, fishing and recreational boats, barges, and the inputs of TBT from the Goa shipyard and dry dock facility situated in the harbour are the probable sources of the DBT and TBT in the samples of the west coast of India. Higher levels of TBT were observed in biofilm relative to that in the surrounding seawater. When fed on TBT contaminated biofilm of the diatom Navicula subinflata, butyltin concentrations in the clam Paphia malabarica increased over the period of feeding suggesting the importance of biofilm in the transfer of butyltins to higher group of organisms.  相似文献   
66.
Freshwater edible catfish Clarias batrachus (Linn.) was treated with sublethal concentration of two different groups of pesticides- carbaryl, a carbamate and phorate, an organophosphate for 24 ,72 ,120 and 168 h. The disorders of lipid metabolism were observed in serum. Cholesterol levels in the serum decreased significantly throughout the exposure period with both the pesticides. These results indicate one significant manifestation of the toxic response from the fish under the stress of pesticide exposure.  相似文献   
67.
The present work aims at identification of multiple drug-resistant pathogenic bacteria in a selected stretch, namely, Puri on the Bay of Bengal, India. Six stations at the coast of Puri were selected and samples of water and sediment were collected during the winter of 2008 and 2009 for this study. Thirty-eight pathogenic bacteria were isolated and identified from both the water and the sediment of 6 fixed stations (PU-1a, PU-1b, PU-2, PU-3, PU-4, and PU-5). The identified pathogens were Escherichia coli, Vibrio cholerae, Vibrio parahaemolyticus, Klebsiella pneumoniae, Staphylococcus aureus, Enterococcus faecalis, Pseudomonas aeruginosa, and Proteus mirabilis. Antibiotic sensitivity of the isolated bacteria was studied by using 12 selected antibiotics, commonly used for the medication of human beings and animals. The isolated pathogens from both the water and the sediment samples showed lowest resistance to chloramphenicol (C-30 μg) where as the pathogens showed highest level of resistance to ampicillin (10-μg) among the antibiotics used for the study. Among the isolated pathogens E. faecalis (PU-1a), P. aeruginosa (PU-2 and PU-3), E. coli (PU-3 and PU-4), and K. pneumonia (PU-4) showed resistance to more than four antibiotics. Out of the isolated species, 57.8% pathogens were multi-drug resistant. Antibiotic resistance indexes of all the stations were calculated and found to be in the range of 0.066 to 0.083.  相似文献   
68.
Objective: The objective of this study was to determine the influence of age and injury mechanism on cervical spine tolerance to injury from head contact loading using survival analysis.

Methods: This study analyzed data from previously conducted experiments using post mortem human subjects (PMHS). Group A tests used the upright intact head–cervical column experimental model. The inferior end of the specimen was fixed, the head was balanced by a mechanical system, and natural lordosis was removed. Specimens were placed on a testing device via a load cell. The piston applied loading at the vertex region. Spinal injuries were identified using medical images. Group B tests used the inverted head–cervical column experimental model. In one study, head–T1 specimens were fixed distally, and C7–T1 joints were oriented anteriorly, preserving lordosis. Torso mass of 16 kg was added to the specimen. In another inverted head–cervical column study, occiput–T2 columns were obtained, an artificial head was attached, T1–T2 was fixed, C4–C5 disc was maintained horizontal in the lordosis posture, and C7–T1 was unconstrained. The specimens were attached to the drop test carriage carrying a torso mass of 15 kg. A load cell at the inferior end measured neck loads in both studies. Axial neck force and age were used as the primary response variable and covariate to derive injury probability curves using survival analysis.

Results: Group A tests showed that age is a significant (P < .05) and negative covariate; that is, increasing age resulted in decreasing force for the same risk. Injuries were mainly vertebral body fractures and concentrated at one level, mid-to-lower cervical spine, and were attributed to compression-related mechanisms. However, age was not a significant covariate for the combined data from group B tests. Both group B tests produced many soft tissue injuries, at all levels, from C1 to T1. The injury mechanism was attributed to mainly extension. Multiple and noncontiguous injuries occurred. Injury probability curves, ±95% confidence intervals, and normalized confidence interval sizes representing the quality of the mean curve are given for different data sets.

Conclusions: For compression-related injuries, specimen age should be used as a covariate or individual specimen data may be prescaled to derive risk curves. For distraction- or extension-related injuries, however, specimen age need not be used as a covariate in the statistical analysis. The findings from these tests and survival analysis indicate that the age factor modulates human cervical spine tolerance to impact injury.  相似文献   

69.
Environmental Science and Pollution Research - The tree species and its diversity are two critical components to be monitored for sustainable management of forest as well as biodiversity...  相似文献   
70.
The disaster clearinghouse concept originates with the earthquake community as an effort to coordinate research and data collection activities. Though prior earthquake clearinghouses are small in comparison to what was needed in response to Hurricane Katrina, these seminal structures are germane to the establishment of our current model. On 3 September 2005, five days after Katrina wrought cataclysmic destruction along the Gulf Coast, FEMA and Louisiana State University personnel met to establish the LSU GIS Clearinghouse Cooperative (LGCC), a resource for centralization and dissemination of geospatial information related to Hurricane Katrina. Since its inception, the LGCC has developed into a working model for organization, dissemination, archiving and research regarding geospatial information in a disaster. This article outlines the formation of the LGCC, issues of data organization, and methods of data dissemination and archiving with an eye towards implementing the clearinghouse model as a standard resource for addressing geospatial data needs in disaster research and management.  相似文献   
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