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41.
This study presents the levels of endocrine disrupting chemicals (EDCs) accumulated by Paraprionospio sp. from the Yodo River mouth, Osaka Bay. Since high concentrations of nonylphenol (NP), bisphenol A (BP), octylphenol (OP), 17β-estradiol (E2), and estrone (E1) have been measured in sediment from Osaka Bay, some bioaccumulation could be expected particularly in benthic animals. EDCs were analysed in Paraprionospio sp., a dominant benthic species in Osaka Bay. The results showed that Paraprionospio sp. had accumulated varying concentrations (wet weight; w.w.) of NP at 1,460–4,410 ng/g; BP at 22.5–39.6 ng/g; OP at 18.9–45.4 ng/g; E2 at 0.89–4.35 ng/g; and E1 at 0.06–2.50 ng/g. Accumulation of NP and OP were highest among the samples gathered in summer (July 2008), while concentrations of BP, E2, and E1 did not much differs within 3 years. EDC levels in Paraprionospio sp. were apparently greater than those in sediments showing bioaccumulation.  相似文献   
42.
Copper recovery is the core of waste printed circuit boards (WPCBs) treatment. In this study, we proposed a feasible and efficient way to recover copper from WPCBs concentrated metal scraps by direct electrolysis and factors that affect copper recovery rate and purity, mainly CuSO4·5H2O concentration, NaCl concentration, H2SO4 concentration and current density, were discussed in detail. The results indicated that copper recovery rate increased first with the increase of CuSO4·5H2O, NaCl, H2SO4 and current density and then decreased with further increasing these conditions. NaCl, H2SO4 and current density also showed a similar impact on copper purity, which also increased first and then decreased. Copper purity increased with the increase of CuSO4·5H2O. When the concentration of CuSO4·5H2O, NaCl and H2SO4 was respectively 90, 40 and 118 g/L and current density was 80 mA/cm2, copper recovery rate and purity was up to 97.32% and 99.86%, respectively. Thus, electrolysis proposes a feasible and prospective approach for waste printed circuit boards recycle, even for e-waste, though more researches are needed for industrial application.
  相似文献   
43.
Environmental Science and Pollution Research - Soil conditioners can be used to compensate for the insufficient soil nutrition and organic matter (OM) of arable soils. However, the traditional...  相似文献   
44.
Environmental Science and Pollution Research - In this study, corn stalk was modified by manganese (Mn) before (MBC1) and after (MBC2) pyrolysis at different temperatures (400~600 °C)...  相似文献   
45.
In this study, bio-thermoset from epoxidized soybean oil (ESO) was prepared in the presence of methylhexahydrophthalic anhydride curing agent and 2-ethyl-4-methylimidazole catalyst. The crosslink densities of the synthesized ESO are ranged from 0.109 × 10?3 to 0.308 × 10?3 mol/cm3. The ESO bio-thermosets were exposed to the soil-burial test for 8 months. Weight change and morphology of the degraded ESO specimens were assessed. It was found that the weight loss of ESO was governed by the materials compositions, crosslink density and the soil-burial exposure time. The 3 mm thickness ESO bio-thermosets with crosslink density of 0.109 × 10?3 mol/cm3 had fully biodegraded after soil-burial for 6 months. In addition, 16S rDNA sequencing was carried out to identify the soil microorganisms. It was suggested that Comamonas sp., Bacillus sp., Streptomyces sp. and Acinetobacter sp. are the possible soil microbes that degrade the ESO bio-thermosets in the compost soil environment.  相似文献   
46.
Nitrogen fertility and abiotic stresses management in cotton crop: a review   总被引:1,自引:0,他引:1  
This review outlines nitrogen (N) responses in crop production and potential management decisions to ameliorate abiotic stresses for better crop production. N is a primary constituent of the nucleotides and proteins that are essential for life. Production and application of N fertilizers consume huge amounts of energy, and excess is detrimental to the environment. Therefore, increasing plant N use efficiency (NUE) is important for the development of sustainable agriculture. NUE has a key role in crop yield and can be enhanced by controlling loss of fertilizers by application of humic acid and natural polymers (hydrogels), having high water-holding capacity which can improve plant performance under field conditions. Abiotic stresses such as waterlogging, drought, heat, and salinity are the major limitations for successful crop production. Therefore, integrated management approaches such as addition of aminoethoxyvinylglycine (AVG), the film antitranspirant (di-1-p-menthene and pinolene) nutrients, hydrogels, and phytohormones may provide novel approaches to improve plant tolerance against abiotic stress-induced damage. Moreover, for plant breeders and molecular biologists, it is a challenge to develop cotton cultivars that can tolerate plant abiotic stresses while having high potential NUE for the future.  相似文献   
47.
近年来,转基因毛状根组织被越来越多地应用于重金属和有机污染物的植物修复技术研究中,已成为进行污染物毒性响应机制研究的便捷的实验室工具。为了探究龙葵、油菜、芥菜3种镉(cadmium,Cd)超富集植物对Cd毒性胁迫响应的差异,以诱导出的3种植物毛状根为研究材料,从毛状根的生长状态、富集Cd的能力、根组织细胞的凋亡程度和抗氧化酶活性等方面进行了探讨。结果表明:Cd浓度为0~50μmol·L-1时,龙葵、油菜、芥菜毛状根受Cd毒害的影响都不明显;Cd浓度为75~100μmol·L-1时,龙葵、油菜、芥菜毛状根均表现出对Cd胁迫的防御响应。在较高的Cd浓度(100μmol·L-1)下,龙葵毛状根的生物量受Cd毒害的影响最小,芥菜次之,油菜受影响最大;同时龙葵毛状根富集的Cd含量最高(745.0μg·g-1),芥菜次之(681.4μg·g-1),油菜最差(505.2μg·g-1)。龙葵、油菜、芥菜毛状根在Cd胁迫下的细胞凋亡水平均随Cd浓度的升高而升高,当Cd浓度为100μmol·L-1时,龙葵毛状根比油菜和芥菜毛状根的细胞凋亡程度均低。同时3种植物毛状根在不同浓度Cd处理下抗氧化酶活性的变化有一定差异。从上述结果综合来看,龙葵毛状根受Cd毒害的影响最小、富集Cd的能力最好,是进一步开展Cd超富集植物转基因改造研究的较好的实验室载体。  相似文献   
48.
Diatoms have been regularly used as bioindicators to assess water quality of surface waters. However, diatom-based indices developed for a specific geographic region may not be appropriate elsewhere. We sampled benthic diatom assemblages in the upper Han River, a subtropical river in China, to evaluate applicability of 14 diatom-based indices used worldwide for water quality assessment. A total of 194 taxa from 31 genera were identified in the dry season and 139 taxa from 23 genera in the wet season. During the dry season, significant relationships were found for all but one of the diatom-based indices (Index Diatom Artois–Picardie) with one or more physical and chemical variables including nutrients and ion concentrations in river waters. The Biological Diatom Index (IBD) and diatom-based eutrophication/pollution index (EPI-D) were strongly related to trophic status and ionic content, while Watanabe’s Index was related to organic pollution and conductivity. Yet, the diatom indices showed weak relationships with physical and chemical variables during the wet season. It suggests that diatom-based indices developed in Europe can be applied with confidence as bioindicators of water quality in subtropical rivers of China, at least during base-flow conditions.  相似文献   
49.
Environmental Science and Pollution Research - This study investigated the coagulation performance of titanium tetrachloride (TiCl4) for leachate treatment and preparation of titanium oxide (TiO2)...  相似文献   
50.
Environmental Science and Pollution Research - The livestock manure nitrogen load on farmland (LMNLF) is often used to assess the potential environmental pollution risk of livestock manure nitrogen...  相似文献   
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