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61.
Cellulase production was carried out by solid state bioconversion (SSB) method using rice straw, a lignocellulosic material and agricultural waste, as the substrate of three Trichoderma spp. and Phanerochaete chrysosporium in lab-scale experiments. The results were compared to select the best fungi among them for the production of cellulase. Phanerochaete chrysosporium was found to be the best among these species of fungi, which produced the highest cellulase enzyme of 1.43 IU/mL of filter paper activity (FPase) and 2.40 IU/mL of carboxymethylcellulose activity (CMCase). The “glucosamine” and “reducing sugar” parameters were observed to evaluate the growth and substrate utilization in the experiments. In the case of Phanerochaete Chrysosporium, the highest glucosamine concentration was 1.60 g/L and a high concentration of the release of reducing sugar was measured as 2.58 g/L obtained on the 4th day of fermentation. The pH values were also recorded. The range of the pH was about 5.15 to 5.56 in the case of Phanerochaete Chrysosporium.  相似文献   
62.
Reclaimed wastewater is an important source of irrigation in semiarid and arid zones. Here we report data on carbamazepine (CBZ) uptake by cucumber plants in hydroponic culture and greenhouse experiments using different soil types irrigated with fresh water or reclaimed wastewater. Data obtained from the hydroponic culture experiments suggest that CBZ is mainly translocated by water mass flow, and thus it is concentrated and accumulated to the largest extent in the mature/older leaves. Carbamazepine concentration in cucumber fruits and leaves was negatively correlated with soil organic matter content. The concentrations of CBZ in the roots and stems were relatively low, and most CBZ in the plant (76-84% of total uptake) was detected in the leaves. A greenhouse experiment using fresh water and reclaimed wastewater spiked, or not, with CBZ at 1 μg L−1 (typical concentration in effluents) revealed that CBZ can be taken up and bioaccumulated from its background concentration in reclaimed wastewater. Bioaccumulation factor (calculated as the ratio of CBZ concentration in the plant to that in the soil solution) for the fruits (0.8-1) was significantly lower than the value calculated for the leaves (17-20).This study emphasizes the potential uptake of active pharmaceutical compounds by crops in organic-matter-poor soils irrigated with reclaimed wastewater and highlights the potential risks associated with this agricultural practice.  相似文献   
63.
The impactof cladocerans metabolic activities on the carbon (C), nitrogen (N) and phosphorus (P) dynamics in Lake Kinneret (Israel) is presented. The study, is based on the incorporation of field data and experimental measurements. Grazing, respiration and production rates of Diaphanosoma spp., Ceriodaphnia spp. and Bosmina spp. were experimentally measured at three temperatures, and the results were extrapolated to the field biomass distribution atthese respective temperatures, and the total lake capacity was calculated using the following equation: consumption = respiration + production + excretion. The field capacity of consumption, respiration and production were found to be mostly correlated with biomass density, but the temporal fluctuation of the percent of excretion from consumed energy differed. The increase in P, decline in N and decrease in the TN/TP mass ratio in the epilimnion of Lake Kinneret during 1969-2004 created N limitation. An increase in C and dedine in TN, with a consequential increase in the C/TN ratio were documented. TP was augmented but the C/TP ratio was only slightly increased. During 1975-2004, P was probably, a minor limitation for cladoceran growth. The positive impact of recycled P by cladocerans underthe N limitation in Lake Kinneret is discussed. There is a current threat on the water quality, derived from N limitation (mostly in summer-fall) and consequent Cyanophyta blooms. Thus, the role of recycled P bygrazers may be significant.  相似文献   
64.
The capability of carbon nanotubes (CNTs) to adsorb lead (Pb) in aqueous solution was investigated. Batch mode adsorption experiment was conducted to determine the effects of pH, agitation speed, CNTs dosage and contact time. The removal of Pb(II) was reach to maximum value 85% or 83% at pH 5 or 40 mg/L of CNTs, respectively. Higher correlation coefficients from Langmuir isotherm model indicates the strong adsorptions of Pb(II) on the surface of CNTs (adsorption capacity Xm = 102.04 mg/g). From this study, the results indicates that the highest percentage removal of Pb (96.03%) can be achieved at pH 5, 40 mg/L of CNTs, contact time 80 min, and agitation speed 50 r/min.  相似文献   
65.
The aim of this study was to determine the efficacy of combined maternal serum alpha-fetoprotein (MSAFP) and maternal serum human chorionic gonadotropin (MShCG) screening in detecting chromosome defects in the first trimester of pregnancy. Sera of 492 women (previously assayed for MSAFP) were analysed for MShCG under code without knowledge of cytogenetic results. Overall, 48 of 492 patients (9·8 per cent) had either an MSAFP multiple of the median ⩽0·5 or an MShCG β/a z ratio multiple of the median ⩽ 0·25, eight of whom had a fetus with a serious chromosome defect. A third of fetuses with Down' s syndrome and 83 per cent with trisomy 18 were detected at a potential‘cost’ of providing chorionic villus sampling or amniocentesis in 8·6 percent of women screened.  相似文献   
66.
Prenatal diagnosis for infantile osteopetrosis was attempted during the third pregnancy of a first-cousin marriage whose family history revealed an affected previous child. At the 25th week of pregnancy, fetal X-ray evaluation revealed marked sclerosis of osteopetrotic bone and metaphyseal splaying and clubbing of both femurs. The pregnancy was terminated and repeated X-rays and histopathological examination of fetal bone (femur) confirmed the diagnosis.  相似文献   
67.
Bioreactor landfills are operated to enhance refuse decomposition, gas production, and waste stabilization. The major aspect of bioreactor landfill operation is the recirculation of collected leachate back through the refuse mass. Due to the accelerated decomposition and settlement of solid waste, bioreactor landfills are gaining popularity as an alternative to the conventional landfill. The addition or recirculation of leachate to accelerate the waste decomposition changes the geotechnical characteristics of waste mass. The daily cover soils, usually up to 20–30% of total MSW volumes in the landfill, may also influence the decomposition and shear strength behavior of MSW. The objective of this paper is to study the effects of daily covers soils on the shear strength properties of municipal solid waste (MSW) in bioreactor landfills with time and decomposition. Two sets of laboratory-scale bioreactor landfills were simulated in a laboratory, and samples were prepared to represent different phases of decomposition. The state of decomposition was quantified by methane yield, pH, and volatile organic content (VOC). Due to decomposition, the matrix structure of the degradable solid waste component was broken down and contributed to a significant decrease in the reinforcing effect of MSW. However, the daily cover soil, a non-degradable constituent of MSW, remains constant. Therefore, the interaction between daily cover soil particles and MSW particles will affect shear strength behavior. A number of triaxial tests were performed to evaluate the shear strength of MSW. The test results indicated that the shear strength of MSW was affected by the presence of cover soils. The friction angle of MSW with the presence of cover soil is higher than the friction angle of MSW without any cover soils. The friction angle of MSW increased from 27° to 30° due to the presence of cover soils for Phase 1 samples. The increased strength was attributed to the friction nature of sandy soil that was used as daily covers soils. Therefore, the effects of cover soils on the shear strength properties of MSW should be evaluated and taken into consideration during stability analyses and design.  相似文献   
68.
A case of retinoic acid embryopathy which was retrospectively diagnosed after delivery is presented. The affected fetus was exposed to the drug during the first month of pregnancy and second-trimester sonographic examination showed hydrocephalus and cardiacmalformation. The diagnosis was made on the basis of autopsy findings and genetic enquiry.  相似文献   
69.
This paper examines the collapse of a five-storey building in Nairobi, Kenya, on 23 January 2006. It draws on reports from local authorities and on debriefings by Israel's Home Front Command (HFC), including information on injury distribution, rescue techniques, and the mode of operation. Most of the 117 people found under the structure were evacuated on the first day to a public hospital, which was overwhelmed by the incident. HFC forces arrived 23 hours after the disaster. At that stage, two people were still buried under the building and special techniques (tunnelling and scalping) were required to secure their evacuation. The two people quickly recovered after a short stay in hospital. Local technology is the preferred option during such events because time is crucial. International cooperation is required when this technology is not available. All of the hospitals in the disaster area, including private facilities, should participate in treating casualties.  相似文献   
70.
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