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The concentration of platinum in the sewage of five European hospitals originating from excreted antineoplastic drugs, cisplatin and carboplatin, was analyzed in a short term study to provide an order of magnitude of Pt emissions from hospitals into aquatic environments. These emissions were compared with a rough estimation of emissions by cars. The average daily concentrations in the hospital effluents were approximately < 10-601 ng l-1 Pt (20-3580 ng l-1 in 2-h mixed samples). As expected from consumption data, the daily average concentrations should range from < 10-710 ng l-1 Pt. Platinum emitted by hospitals is 3.3-12.3% (1.3-14.3 kg per year) the estimated amount emitted by cars equipped with catalytic converters in the different European countries. Compared to platinum emissions from other sources, the effluents of hospitals are a minor source of platinum in municipal sewage, but they should not to be disregarded. Other possible sources for the emission of platinum into the environment should be considered in further investigations.  相似文献   
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The aim of this study was to investigate the degree of contamination of sewage sludge with ESBL-producing Escherichia coli strains and the effectiveness of different sewage sludge treatment methods.Monthly sewage sludge samples were collected between January and September 2009 in 5 different sewage treatment plants and tested for the presence of ESBL E. coli. In addition, the number of colony forming units (CFU) of E. coli and coliform bacteria before and after the different sludge treatment methods (aerobic/anaerobic digestion, lime stabilization, and thermal treatment) was investigated.Of the 72 sewage sludge samples investigated, ESBL-positive E. coli were found in 44 (61.1%) sewage sludge samples. The classification of β-lactamase groups was carried out in 15 strains resulting in the detection of 2 different groups (CTX-M and TEM) of bla genes. All 15 of them had a CTX-M gene and 4 of these strains furthermore carried a TEM gene.With regard to the CFU of E. coli and coliform bacteria, thermal treatment and lime stabilization following dehydration sufficiently reduced pathogen concentrations. The plants using merely stabilization and dehydration showed an increase of E. coli and coliform bacteria and thus also an increase in ESBL-producing E. coli.  相似文献   
3.
Antibiotic resistance of E. coli in sewage and sludge   总被引:6,自引:0,他引:6  
The aim of the study is the evaluation of resistance patterns of E. coli in wastewater treatment plants without an evaluation of basic antibiotic resistance mechanisms.Investigations have been done in sewage, sludge and receiving waters from three different sewage treatment plants in southern Austria. A total of 767 E. coli isolates were tested regarding their resistance to 24 different antibiotics. The highest resistance rates were found in E. coli strains of a sewage treatment plant which treats not only municipal sewage but also sewage from a hospital.Among the antimicrobial agents tested, the highest resistance rates in the penicillin group were found for Ampicillin (AM) (up to 18%) and Piperacillin (PIP) (up to 12%); in the cephalosporin group for Cefalothin (CF) (up to 35%) and Cefuroxime-Axetil (CXMAX) (up to 11%); in the group of quinolones for Nalidixic acid (NA) (up to 15%); and for Trimethoprime/Sulfamethoxazole (SXT) (up to 13%) and for Tetracycline (TE) (57%).Median values for E. coli in the inflow (crude sewage) of the plants were between 2.0 x 10(4) and 6.1 x 10(4)CFU/ml (Coli ID-agar, BioMerieux 42017) but showed a 200-fold reduction in all three plants in the effluent. Nevertheless, more than 10(2)CFU E. coli/ml reached the receiving water and thus sewage treatment processes contribute to the dissemination of resistant bacteria in the environment.  相似文献   
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In wineries, unwanted microorganisms present not only hygienic problems but also have a negative influence on wine quality. An evaluation of Austrian/Styrian wine cellars with regard to the volume and the composition of the mycoflora is very important both for the process of wine production and for occupational safety.Thirty-six wine cellars of 20 vintners were investigated with regard to microorganisms in the air and on material surfaces. Moreover, the presence of trichloroanisole in the air was determined by means of solid-phase micro-extraction. Microorganisms were sampled using the six-stage Andersen-Cascade impactor.The results showed that the concentrations of xerophilic fungi in the air of cellars with large visible mold areas (> 80%) reached values up to 1.4 × 104 colony forming units per m³. In the wine cellars fourteen predominant fungal genera were found in the indoor air, the most frequent was Penicillium. Trichloroanisole was detected in the air of wine cellars with large visible moldy patches. The spore concentrations in the cellar air were two times higher in cellars with Zasmidium cellare growth than in cellars without Z. cellare.These results will serve as a database for further studies.  相似文献   
5.
The author suggests that as readily available technology is forcing changes in precollege mathematics education that have been long overdue, it is no longer obvious just what the `basics' are. Furthermore, a shift in focus, from preparation exclusively for the hard sciences and engineering to preparation that includes combinatorics and the other discrete topics recommended and outlined in the NCTM's `Curriculum and Evaluation Standards for School Mathematics' published in March 1989, has contributed to the confusion. She considers who the students are that high school teachers have tended to identify as the best math students and who the students are who have tended to go on into engineering, noting that they are not always the same people. She then considers changes in mathematics education in terms of student needs  相似文献   
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