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1.
简要阐述了高效型离心脱水机的工作原理及其在上海两个污水处理厂进行的现场污泥脱水实验,结果表明,污泥脱水效果良好,从污泥性状与脱水性分析说明,污泥浓度低,有机物含量高,则脱水性差;有机物含量低,则脱水性好,应用分析表明,随着污泥性状逐年变化,离心脱水机将成为流脱水机。  相似文献   
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We compared the quantity and quality of the epicuticular wax of diapause and non-diapause pupae in two closely related Pieris species, P. brassicae and P. rapae crucivora. Main components of their epicuticular wax were identified as hydrocarbons. In P. brassicae, more than 95% of hydrocarbons were saturated regardless of whether the pupae were in diapause or not. In P. rapae crucivora, 93% of hydrocarbons were saturated in non-diapause pupae whereas in diapause pupae 41% were saturated and 59% unsaturated. From measurements of body surface area by nuclear magnetic resonance microimaging, we calculated the average thickness of the wax layer. The thickness in diapause and non-diapause pupae of P. brassicae was 800 and 160 nm, respectively. In P. rapae crucivora, the thickness was 195 nm in diapause and 11 nm in non-diapause. This is the first report to clarify the compositional difference in epicuticular wax between diapause and non-diapause pupae.  相似文献   
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Diets of the demersal fishes on the shelf off Iwate,northern Japan   总被引:2,自引:0,他引:2  
Diets of demersal fishes were determined on the shelf (ca. 130 m deep) off Iwate, Japan. Samples were taken in three different types of habitat, an artificial reef (AR) site, a natural reef (NR) site, and sandymud bottom (SB) site, from May 1987 to September 1991, mostly every two months. A total of 67 prey items were recognized in the stomachs of 45 predator fish species. The most important preys were the pelagic fishes Sardinops melanostictus and Engraulis japonicus, which comprised 37% wet wt of the overall stomach contents. The percentage of pelagic fishes was highest at AR site, where fish density was highest. The dominant ten species could be divided into five feeding types. The pelagic fish feeders Physiculus maximowiczi and Gadus macrocephalus fed mainly on S. melanostictus. The dietary breadth of P. maximowiczi was wide, while that of Gadus macrocephalus was narrow. The pelagic crustacean feeder Theragra chalcogramma mostly consumed Themisto japonica and euphausiids and showed the least dietary overlap with other fishes. Benthic fish feeders were Hemitripterus villosus and Liparis tanakai. The benthic crustacean feeders Alcichthys alcicornis and Hexagrammos otakii consumed benthic crustaceans as well as pelagic and benthic fishes and showed the largest dietary breadth. The benthic invertebrate feeders Gymnocanthus intermedius, Dexistes rikuzenius and Tanakius kitaharai fed mainly on polychaetes and benthic crustaceans. But Gymnocanthus intermedius consumed a significant proportion of pelagic fishes. Ontogenetic dietary shift was recognized for these fishes. Pelagic fishes were consumed more intensively by larger individuals, especially true of A. alcicornis, Theragra chalcogramma and Gadus macrocephalus. Predominancy of the two most adundant species, P. maximowiczi and A. alcicornis, may be supported by their wide dietary breadth and the significant proportion of pelagic fish in their diets. Interspecific dietary overlap was low in most cases suggesting that food resources were well partitioned, although some high overlap was observed among the pelagic fish feeders, A. alcicornis, and Gymnocanthus intermedius, and among the benthic invertebrate feeders. Interspecific competition seemed more likely in the benthic invertebrate feeders than in the pelagic fish feeders partly because of superabundance of the pelagic prey S. melanostictus.  相似文献   
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The first example of a ruthenium sensitizer (TUS-22) having a natural dye, bisdemethoxycurcumin, as a ligand has been synthesized. The dye-sensitized solar cell based on this novel dye showed 5.8% conversion efficiency under AM 1.5 (100 mW/cm2) irradiation.  相似文献   
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A commercially available enzyme-linked immunosorbent assay (ELISA) kit was evaluated for the determination of toxic equivalents (TEQs) of dioxin-like polychlorinated biphenyls (PCBs) in retail fish. The ELISA was highly specific for 2,3',4,4',5-pentachlorobiphenyl (PCB 118), which is generally the most abundant dioxin-like PCB isomer found in fish. The quantitative limit of the ELISA (using 3,3',4'-trichloro-4-methoxybiphenyl as a surrogate standard for PCB 118) was 10 ng ml(-1) (125 pg assay(-1)) in the standard curve, corresponding to 50 pg PCB 118 g(-1) in the tested sample. Good recoveries of PCB 118 (78.7-112.3%) were obtained for spiked purified fish extracts according to the ELISA. Good linearity was also obtained in dilution tests using purified fish extracts. No significant interference of the matrix was observed in the ELISA when this purification procedure was used. Recovery tests in which PCB 118 was added to fish samples also resulted in acceptable recoveries (60.2-82.3%) in the ELISA following purification. The ELISA results for fish samples correlated well with the TEQ concentrations of dioxin-like PCBs obtained by high-resolution gas chromatography/high-resolution mass spectrometry (r = 0.92, n = 26). These data indicate that the ELISA kit is suitable for screening retail fish for the TEQs of dioxin-like PCBs.  相似文献   
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We used Lagrangian numerical simulations to examine the trans-Pacific dispersal processes of loggerhead turtle hatchlings. Ten thousand simulated particles were released from each of the three nesting regions in Japan and tracked for 5 years. Results showed many particles moving eastward, drifting in the Kuroshio Current followed by the Kuroshio Extension Current. However, no particles reached Baja California, a known feeding area, through passive processes, indicating that trans-Pacific transportation requires active swimming by turtles. The duration of the trans-Pacific dispersal was estimated to be at least 1.6–3.4 years, with some turtles drifting in the Kuroshio Countercurrent and remaining in the western Pacific even after 5 years. This indicates that as revealed by previous genetic studies, not all loggerheads always disperse along a trans-Pacific route. The findings showed that survival and expected growth rates varied widely according to ambient temperatures during drifting, which in turn depended on nesting location.  相似文献   
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This paper considers three questions concerning a low-carbon society. The first is the implication of a 50% reduction in greenhouse gases (GHGs) by 2050. In the Intergovernmental Panel on Climate Change (IPCC) Fourth Assessment Report, released in 2007 (IPCC 2007b; http://www.gtp89.dial.pipex.com/chpt.htm), the suggested limit of increase in average worldwide temperatures is 2–3°C above the current level, but is this consistent with a 50% reduction by 2050? Second, when a 50% reduction in global emissions is envisioned, what is the level of reduction needed in Japan? Should the 50% reduction be uniform for advanced industrial countries and developing countries, or differentiated based on a country’s emissions? Third, how feasible are emission reduction targets in Japan? Even if the emission reduction target set for each country takes into account climate change impact and equity, whether the target is technically, or socially and economically, acceptable is another matter.  相似文献   
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Food and Environmental Virology - Influenza A virus (IAV) infection is perennially one of the leading causes of death worldwide. Effective therapy and vaccination are needed to control viral...  相似文献   
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