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21.
Horai S Minagawa M Ozaki H Watanabe I Takeda Y Yamada K Ando T Akiba S Abe S Kuno K 《Chemosphere》2006,65(4):657-665
Concentrations of 22 elements (Mg, V, Cr, Mn, Fe, Co, Ni, Cu, Zn, As, Se, Rb, Sr, Mo, Ag, Cd, Sb, Cs, Ba, Tl, total Hg (T-Hg), Pb) and organic Hg (O-Hg) were examined in the liver, kidney and brain of the Javan mongoose (Herpestes javanicus) and in liver of the Amami rabbit (Pentalagus furnessi) from Amamioshima Island in Japan. Relatively high levels of T-Hg levels (from 1.75 to 55.5 microg g-1 wet wt.) were found in the Javan mongoose. As for a comparison of hepatic T-Hg concentrations between the two areas, there was no significant difference between the Javan mongoose in Amamioshima and those in the Okinawa islands. In addition, T-Hg levels in the livers of the Amami rabbit were the same as in the livers of other herbivorous mammals. Taken together, it suggested that T-Hg accumulation in the livers of the Javan mongoose was not affected by the environment but by a specific physiological mechanism. The comparison of Hg and other heavy metal accumulations between terrestrial mammals (13 species, 61 individuals) including the Javan mongoose and marine mammals (18 species, 508 individuals) were also discussed. 相似文献
22.
Ohe Y 《Journal of environmental management》2011,92(3):886-891
Farm diversification by farmers' open-door policy generates opportunities for farmers to internalize externalities of multifunctionality. Although the educational function of agriculture is an example of such an open-door policy and is attracting growing attention, this function has been little explored. To promote farm diversification in this direction, this paper examined how and to what degree farmers internalize externalities of multifunctionality by focusing on the educational function provided by dairy farming, i.e., farming experience services, in Japan. The main findings were as follows. First, we can say that the educational function is determined by ordinary technical jointness as well as institutional jointness, which is represented by food culture and the agrarian heritage. Both the technical and institutional jointness enhanced the externality. Because of these two working factors, there is a U-shaped relationship between farm diversification and provision of farming experience services. Second, however, an empirical evaluation indicated that farmers only partially internalize educational externalities by treating them as supplementary services combined with processed milk products. Therefore, appropriate integrated management of these newly emerging educational services to become a viable market should be fully addressed in the future, especially for family farms. 相似文献
23.
Hiroyasu Yamazaki Masayuki Terada Akira Tsuboi Chizuyo Matsubara Toshiaki Hata Yasuo Kakiuchi 《毒物与环境化学》2013,95(1-2):71-81
Orally administered 3H‐benzo(a)pyrene (BP) was persistent in protein fraction of liver, lung and kidney. The radioactivity in this fraction increased with time after administration and accounted for about 50%, 40% and 65% of total radioactivity in liver, lung and kidney, respectively at 48 hr. The BP metabolites binding proteins were located in cytosol and had molecular weights of 40,000–60,000 and 80,000–100,000 as determined by gel filtration and polyacrylamide gel disc electrophoresis. In addition, at 48hr after administration, about 80% of radioactivity in high molecular weight protein fraction was found to be precipitated by trichloroacetic acid treatment. These results suggest that BP metabolites might be transported by and are persistent in these protein fractions of liver, lung and kidney if the intake of BP is continuous. These proteins, therefore, appeared to be closely related to cell toxicity or mutagenicity in these organs as well as DNA. 相似文献
24.
一组高效稳定纤维素分解菌复合系MC1的筛选及功能 总被引:92,自引:9,他引:83
从4种堆肥样品中分别筛选出纤维素分解能力较强的4组混合菌,再以酸碱反应互补的原则重新优化组合并驯化成1组纤维素分解能力非常强而稳定的纤维素分解菌复合系MC1.100mL培养物在50℃静止培养72h,分别可分解0.48g滤纸、0.49g脱脂棉、0.19g麦秆和0.08g锯末.分解滤纸时,第24h CMC糖化力最高,为122.3U·mL-在初始pH4~10的不同培养基上接种,均能把pH调到中性,最后稳定在8.0~8.5之间.在连续投放滤纸情况下纤维素分解能力稳定保持20d以上,其发酵液的pH在有滤纸时稳定在6.0~6.5之间,没有滤纸时稳定在8.0~8.5之间. 相似文献
25.
Mesostructured iron oxyhydroxide (FeO x ) and iron oxyhydroxide–phosphate (FeO x P) composites were organized using dodecylsulfate surfactant as a template. X-ray diffraction studies depicted a lamellar structure of the product. Ion exchange and solvent extraction methods were employed for the removal of the surfactant. Carboxylate ions exchanged lamellar type mesostructured material reorganized to a wormhole-like mesoporous material when heated under N2 atmosphere. Surfactant was completely removed by carboxylate ions as observed by the Fourier transform infrared spectra. High surface area acetate-exchanged FeO x (230 m2 g?1) was obtained after the surfactant removal from the composite (2.8 m2 g?1). Surface area of acetate-exchanged FeO x P was the highest (240 m2g?1) after the removal of the surfactant. Local structure of iron species of FeO x was investigated by X-ray absorption fine structure spectroscopy. Further, Fe···Fe bond appeared at 3.21–3.25 Å with coordination number 2–3, showing a high degree of un-saturation of Fe···Fe bonds. As compared with bulk iron oxyhydroxide and iron-intercalated montmorillonite, the mesoporous iron materials were highly effective for arsenic removal from low concentrations of aqueous solutions. Furthermore, mesoporous iron materials were stable in aqueous phase. 相似文献
26.
Hiroyasu Yamazaki Hiroto Kumahashi Noriko Masuda Takeo Kishi Yasuo Kakiuchi Kazuhito Watabe Masaomi Kondo 《Chemosphere》1982,11(3):337-347
Orally administered 3H-benzo(a)pyrene (BP) was concentrated in liver, kidney and lung of rat. Liver contained BP-diols, BP-quinones and 3-hydroxy-BP, and extremely high amounts of BP-quinones and unmetabolized BP were found in lung until after 7 hr of administration. In kidney, BP-quinones and BP-diols were major metabolites, but not BP or 3-hydroxy-BP. Low level of metabolites as conjugates with glucuronate and more polar compounds were also detected in kidney. These results suggested that an orally administered BP was metabolized to BP-diols and 3-hydroxy-BP mainly in liver, to BP-quinones mainly in lung, and to BP-diols and glucuronides or more polar compounds mainly in kidney. 相似文献
27.
基于2H&18O和水化学成分的永定河流域地下水循环特征解析 总被引:2,自引:0,他引:2
运用环境同位素和水化学成分作为水循环研究的示踪剂, 揭示了永定河流域中下游地下水
循环特征。通过现场调查并对浅层和深层地下水采样, 进行室内水化学和氢氧同位素组成测定, 分
析了流域内深层和浅层地下水的氢氧同位素和水化学组成的空间分布规律和演化趋势, 揭示了流
域地下水循环特征。结果表明, 降水是山前地下水的主要补给源, 地下水在接受降水的补给后经过
了不同程度的蒸发作用, 山区受蒸发影响较小, 平原区较大, 尤其是平原区浅层地下水呈现出强烈
的蒸发浓缩作用; 水化学特征表现为自西部山区到山前平原至滨海平原, 自浅层到深层, 地下水的
矿化度逐渐升高; 平原区浅层和深层地下水含水层之间存在明显的越流补给现象; 沿海地区未发现
海水入侵现象。 相似文献
28.
Yucai Lü Xiaofen Wang Ning Li Xiaojuan Wang Masaharu Ishii Yasuo Igarashi Zongjun Cui 《环境科学学报(英文版)》2011,23(4)
An efficient cellulose degrading bacteria exists in the thermophilic wheat straw-degrading community, WDC2. However, this strain cannot be isolated and cultured using conventional separation techniques under strict anaerobic conditions. We successfully isolated a strain of effective cellulose degrading bacteria CTL-6 using a wash, heat shock, and solid-liquid alternating process. Analysis of its properties revealed that, although the community containing the strain CTL-6 grew under aerobic conditions, the purified strain CTL-6 only grew under anaerobic culture conditions. The strain CTL-6 had a striking capability of degrading cellulose (80.9% weight loss after 9 days of culture). The highest efficiency value of the endocellulase (CMCase activity) was 0.404 μtmol/(min-mL), cellulose degradation efficiency by CTL-6 was remarkably high at 50-65°C with the highest degradation efficiency observed at 60°C. The 16S rRNA gene sequence analysis indicated that the closest relative to strain CTL-6 belonged to the genus Clostridium thermocellum. Strain CTL-6 was capable of utilizing cellulose, celiobiose, and glucose. Strain CTL-6 also grew with Sorbitol as the sole carbon source, whereas C.therrnocellum is unable to do so. 相似文献
29.
Sorption behavior of selenium on humic acid under increasing selenium concentration or increasing solid/liquid ratio 总被引:2,自引:0,他引:2
Kamei-Ishikawa N Nakamaru Y Tagami K Uchida S 《Journal of environmental radioactivity》2008,99(6):993-1002
The sorption of selenium (Se) on humic acid (HA) was investigated in order to better understand the fate of stable and radioactive Se in soils and sediments. An ultrafiltration technique was used to determine size distributions of HA-sorbed-Se when increasing Se concentration and solid/liquid ratio. The results showed that the Se sorption onto HA followed the Freundlich isotherm. No solid/liquid ratio-dependence was observed especially when <3 kDa molecular size fraction was used from solid/liquid separation. The Freundlich isotherm parameters K(F) and n obtained using the <3 kDa molecular size fraction for solid/liquid separation were 3.7 x 10(2) and 0.82, respectively. In addition, since dissolved HA increased with decreased ionic strength in the HA suspension, ionic strength could promote aggregation of HA. The conformational change of HA could affect the sorption behavior of Se on HA. 相似文献
30.
Yoshiaki Tsuzuki Masato Fujii Yasuo Mochihar Kouki Matsu Minoru Yoneda 《环境科学学报(英文版)》2010,22(6):892-897
The first social experiment program in Japan to reduce domestic wastewater pollutant discharge by “soft interventions” in households
has been conducted in the Yamato-gawa River drainage area since 2005. The Yamato-gawa River has been listed as one of the worst
water quality rivers in Japan because of the larger annual average BOD. “Hard interventions” including deployment of wastewater
treatment facilities and artificial installation of natural purification facilities in the river has been conducted in these years to improve
river water quality. At the first Yamato-gawa River social experiment program (YR-SEP) in March 2005, BOD at the monitoring point
near the river mouth decreased about 6% during the Program. Natural purification e ect along the river was evaluated in this article
with one-dimensional water quality model for the six river sections. Larger biological oxygen consumption rate, kb, was estimated in
the sections with artificially installed natural purification facilities. The e ect of “soft interventions” in households in the YR-SEP was
estimated as 25% BOD decrease in the nearest monitoring point to the river mouth, when all the households participate in the Program
and BOD discharge reduction rate with “soft interventions” in households was 40%. 相似文献