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91.
Abstract

Studies were conducted to determine the metabolic fate of chloramphenicol (CAP) in White Leghorn using the l4C‐labelled compound. In one experiment birds were administered orally via intra‐crop, a single dose of 100 mg (equivalent to 66 mg kg‐1 body weight) of CAP containing 14 μCi 14C‐CAP, and its absorption, elimination and distribution in plasma were recorded. Orally dosed 14C‐compound was rapidly absorbed, efficiently distributed in plasma and eliminated in excreta (>70% in 5 hr). After 5 h, CAP equivalent residues in tissues were lower than 15 μg g‐1 for this treatment. In a second experiment birds were given intra‐crop dose of either 0.5 or 5 mg of CAP (each dose contained 2.5 μCi 14C‐CAP) daily for five consecutive days followed by a seven day withdrawal period and elimination of 14C in excreta and eggs was monitored. More than 95% of the administered 14C was eliminated within the first 24 h after dosing. Radiocarbon (14C) was deposited preferentially in yolks compared to albumen or other tissues. Residues declined when feeding was stopped. Various metabolites were isolated and identified by a combination of TLC, LC, and LC‐MS. The main metabolic route of CAP in laying hens appears to be the glucuronidation. Cleavage of the dichloroacetate moiety was only a minor route.  相似文献   
92.
Environment, Development and Sustainability - Since 2015, the United Nations sustainable development goals (SDGs) agenda 2030 has been designed with 17 goals, 169 targets, and 232 unique indicators...  相似文献   
93.
94.
Municipal solid waste management was studied for 1 year in a representative urban area of Lahore city for environmental sustainability. The effects of financial status of the household and the seasonal variations on generation rate and compositions of municipal solid waste (MSW) were determined. MSW generation rate and the economic status of the households were positively correlated (p < 0.05). Seasonal variations observed were significant only for organics (p = 0.001), plastics (p = 0.008) and food waste fractions (p = 0.009) in MSW. Response surface regression model developed and analysed by Minitab-15® showed that the interaction of season and different economic zones of the town on the MSW generation rate was non-significant (p = 0.334). Elemental and heating value analyses of the mixed organic fractions in kitchen waste had carbon 47.93%, hydrogen 6.20%, nitrogen 2.24%, sulphur 0.23%, oxygen 39.01%, and C and N ratio 27.78. Findings concluded that food waste was 56% of total MSW with 71.03% moisture content and a modest heating value of 5566 J/g. Existing temporary storage capacity of MSW is 51% of the total MSW generated considering the weighted MSW generation rate of 0.57 kg/person/day calculated in this study. Composting could be a possible final disposal option due to high moisture and organic content and can be studied in future research. Development of a transfer station, introduction of home composting programmes and awareness towards proper segregation and reduction of waste at the household level is suggested to attain sustainability in the MSW management system.  相似文献   
95.
This paper attempts to explain the various factors affecting production of dimorphic males in Euterpina acutifrons. Experiments conducted by crossing different males with virgin females under laboratory conditions have shown that both environmental and genetical factors contribute to the production of dimorphic males in nature.  相似文献   
96.
97.
The fate of trace elements (like Ca, Fe, Al, Pb, K, and Cu) in various pulses (mash, mung, lentils and red kidney beans) of Pakistan has been studied. Samples were collected from two districts (Mansehra and Rawalpindi) and analyzed by wet acid digestion method using atomic absorption spectrophotometry. Experimental results show that the intensity of heavy metal accumulation in plants depends upon the type of the soil, the species of plants, the physicochemical properties of heavy metals, and their content in the soil. The obtained values were compared with the World Health Organization (WHO) standards for food quality. The grains from District Mansehra contained greater amount of trace metals as compared to those collected from District Rawalpindi. However, those values did not exceed the upper limits described by the WHO in nearly all the cases. Based on these findings, the consumption of pulses in larger amounts may easily be recommended.  相似文献   
98.
Environmental Science and Pollution Research - Arsenic (As) bioremediation has been an economical and sustainable approach, being practiced widely under several As-contaminated environments....  相似文献   
99.
Environmental Science and Pollution Research - Soil pollution due to potentially toxic elements is a worldwide challenge for health and food security. Chelate-assisted phytoextraction along with...  相似文献   
100.
Environmental Science and Pollution Research - This study intends to test the presence of β-convergence in the global Environmental Performance (EP). For this purpose, spatial Green Solow...  相似文献   
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