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871.
Su-fen Yuan Ze-hua Liu Hai-Xian Lian Chuangtao Yang Qing Lin Hua Yin Zhi Dang 《Environmental science and pollution research international》2016,23(19):19116-19125
A simple online headspace solid-phase microextraction (HS-SPME) coupled with the gas chromatography-mass spectrometry (GC-MS) method was developed for simultaneous determination of trace amounts of nine estrogenic odorant alkylphenols and chlorophenols and their derivatives in water samples. The extraction conditions of HS-SPME were optimized including fiber selection, extraction temperature, extraction time, and salt concentration. Results showed that divinylbenzene/Carboxen/polydimethylsiloxane (DVB/CAR/PDMS) fiber was the most appropriate one among the three selected commercial fibers, and the optimal extraction temperature, time, and salt concentration were 70 °C, 30 min, and 0.25 g/mL, respectively. The developed method was validated and showed good linearity (R 2?>?0.989), low limit of detection (LOD, 0.002–0.5 μg/L), and excellent recoveries (76–126 %) with low relative standard deviation (RSD, 0.7–12.9 %). The developed method was finally applied to two surface water samples and some of these target compounds were detected. All these detected compounds were below their odor thresholds, except for 2,4,6-TCAS and 2,4,6-TBAS wherein their concentrations were near their odor thresholds. However, in the two surface water samples, these detected compounds contributed to a certain amount of estrogenicity, which seemed to suggest that more attention should be paid to the issue of estrogenicity rather than to the odor problem. 相似文献
872.
Chia-Yi Liu 《Journal of Agricultural and Environmental Ethics》2016,29(4):607-630
A number of high-profile mislabeling incidents have led to many studies exploring the decision-making processes that firms make around performing illegal acts. However, it remains unclear why the proportion of firms conducting these acts constantly fluctuates and never disappears. Therefore, this study investigated this by carrying out a longitudinal analysis of food labeling in the Taiwanese rice industry. Drawing on the institutional isomorphism theory, it was found that the degree of mislabeling is negatively correlated with both the level of control of inspection regulations and public attention toward food regulations, and positively correlated with the previous proportion of firms mislabeling their products. Thus, there is a feedback loop between regulatory control, public attention, and the amount of mislabeling, with the amount of mislabeling not only being affected by the former degree of regulatory control, public attention, and mislabeling, but also modifying the future status of each of these. These findings further our understanding of the causal effects of illegal actions in the institutional agricultural environment. 相似文献
873.
Biochar increased water holding capacity but accelerated organic carbon leaching from a sloping farmland soil in China 总被引:2,自引:0,他引:2
874.
Yi-Tang Chang Jiunn-Fwu Lee Keng-Hua Liu Yi-Fen Liao Vivian Yang 《Environmental science and pollution research international》2016,23(5):4024-4035
Nonionic surfactant-modified clay is a useful absorbent material that effectively removes hydrophobic organic compounds from soil/groundwater. We developed a novel material by applying an immobilized fungal laccase onto nonionic surfactant-modified clay. Low-water-solubility polycyclic aromatic hydrocarbons (PAHs) (naphthalene/phenanthrene) were degraded in the presence of this bioactive material. PAH degradation by free laccase was higher than degradation by immobilized laccase when the surfactant concentration was allowed to form micelles. PAH degradation by immobilized laccase on TX-100-modified clay was higher than on Brij35-modified clay. Strong laccase degradation of PAH can be maintained by adding surfactant monomers or micelles. The physical adsorption of nonionic surfactants onto clay plays an important role in PAH degradation by laccase, which can be explained by the structure and molecular interactions of the surfactant with the clay and enzyme. A system where laccase is immobilized onto TX-100-monomer-modified clay is a good candidate bioactive material for in situ PAHs bioremediation. 相似文献
875.
Shaonan Hao Xuyong Li Yan Jiang Hongtao Zhao Lei Yang 《Environmental science and pollution research international》2016,23(18):17953-17968
The rapid growth of urbanization and industrialization, along with dramatic climate change, has strongly influenced hydrochemical characteristics in recent decades in China and thus could cause the variation of pH and general total hardness of a river. To explore such variations and their potential influencing factors in a river of the monsoon climate region, we analyzed a long-term monitoring dataset of pH, SO4 2?, NOx, general total hardness (GH), Mg2+, Ca2+, and Cl? in surface water and groundwater in the Luan River basin from 1985 to 2009. The nonparametric Seasonal Kendall trend test was used to test the long-term trends of pH and GH. Relationship between the affecting factors, pH and GH were discussed. Results showed that pH showed a decreasing trend and that GH had an increasing trend in the long-term. Seasonal variation of pH and GH was mainly due to the typical monsoon climate. Results of correlation analysis showed that the unit area usage amounts of chemical fertilizer, NO3 ?, and SO4 2? were negatively correlated with pH in groundwater. In addition, mining activity affected GH spatial variation. Acid deposition, drought, and increasing the use of chemical fertilizers would contribute to the acidification trend, and mining activities would affect the spatial variation of GH. Variations of precipitation and runoff in semi-arid monsoon climate areas had significant influences on the pH and GH. Our findings implied that human activities played a critical role in river acidification in the semi-arid monsoon climate region of northern China. 相似文献
876.
ZhiYing Yan XiuLi Wei YueXiang Yuan ZhiDong Li Dong Li XiuFeng Liu 《Journal of the Air & Waste Management Association (1995)》2016,66(4):420-428
Odor pollution is a big environmental problem caused by large-scale livestock production in China, and developing a practical way to reduce these odors is pressing. In this study, a combination of 0.2–1.0 U/mL lignin peroxidase (LiP) and one of three peroxides (H2O2, CaO2, 2Na3CO3·3H2O2) was examined for its efficiency in reducing the release of eight chemicals (propionic acid, isobutyric acid, isocaproic acid, isovaleric acid, phenol, p-cresol, indole, and skatole), NH3, H2S, and odor intensity from pig manure. The results showed an approximately 90% reduction in p-cresol, 40–60% reduction in odor intensity, 16.5–40% reduction in indolic compounds, and 25–40% reduction in volatile fatty acids. Being the electron acceptors of LiP, 2Na3CO3·3H2O2 and CaO2 performed better than H2O2 in reducing the concentration of eight chemicals, NH3, H2S, and odor intensity from pig manure. The effect of deodorization can last for up to 72 hr.
Implications: In China, one of the major environmental problems caused by confined feeding is odor pollution, which brings a major threat to the sustainability, profitability, and growth of the livestock industry. To couple the LiP with the electron acceptors, a low–cost, simple, and feasible method for odor removal was established in this study. Based on the study results, a practical treatment method was provided for odor pollution and supply the farm operators a more flexible time to dispose treated manure. 相似文献
877.
Rebound effect derived from energy efficiency improvement has been widely invested. However, most of studies focus on the rebound effect of the energy composite level and neither distinguish nor compare different energy types. We compare the differences in energy saving and energy rebound between primary and secondary energy sources, and further decompose the rebound effect into production rebound part and final demand component. To do so, we add a module for rebound into a comparative state China-CGE model. We design and test two simulation scenarios using the model. In Scenario 1, all production sectors’ energy efficiency of using primary energy increases by 5%. In Scenario 2, all production sectors’ energy efficiency of using secondary energy increases by 5%. The results show that Scenario 2 leads to more GDP growth and more energy saving. Our scenarios show rebound effects range between 9.6% and 27.9%, and in general are higher when energy efficiency of using primary energy sources is improved. Our decomposition analysis shows that improving energy efficiency in production sectors would stimulates energy use of final demand. Indeed, the consumption side has significant contribution to rebound in secondary energy use, especially in crude oil and gas. This study reveals that improving efficiency of using secondary energy is better than improving that of primary energy, both in terms of economic impact and energy rebound. And complementary policies that prevent energy services prices from falling too much can be adopted to reduce rebound. Controlling residential energy use could also be effective in reducing rebound, this has particular implication to economies in which residential energy consumption are far from saturation. 相似文献
878.
Energy service is an effective way to promote energy conservation by market mechanisms, including energy saving services, energy procurement, supply of many varieties of energy, supply of renewable energy technologies, energy-related consulting services, risk management, etc. China is a major energy consumer but energy is in short supply, and the efficiency of energy use is low. China’s energy service industry has expanded rapidly, in terms of both the number of new Energy Service Companies entering the market and amount of capital invested in Energy Performance Contracting projects, but the energy service sector in China is still at an early stage of development. Developed countries began early in developing the energy service sector and their energy service market is mature, and the experience of developed countries shows that energy services play a significant role in advancing energy saving and emission reduction. Under the new situation, China needs combine energy services experience of developed countries, and take following measures to accelerate China’s energy services rapid and healthy development, including the long-term aspects of policy planning, energy-saving core technology, finance and capital investment, public sector reductions, personnel training, and so on. 相似文献
879.
对西昌高原鳅(Triplophysa xichangensis)人工繁殖中的催产药物及其剂量、受精方式、孵化方法和仔鱼水花培育方法等一系列关键技术进行了详细研究。结果表明,对性腺发育至Ⅳ+~Ⅳ++期的雌鱼分二次注射LRH-A2 0.1μg/g(鱼体重)和HCG 20 IU/g(鱼体重),雄鱼剂量减半,注射量0.1 mL,能很好地促进雌雄鱼发情并产卵排精,在水温19±0.5℃时的效应时间为30.5~31 h;在一个特制的塑料盆中完成了亲鱼培育、打针催产、发情、自然产卵受精、孵化以及仔鱼培育等全部人工繁殖过程,受精率、孵化率和仔鱼水花培育20 d的成活率平均分别为97.2%、85%和85%。本研究成果可应用于西昌高原鳅规模化繁育,对长江上游鱼类生物多样性保护有着积极意义。 相似文献
880.
Larval amphibians are particularly likely to encounter variation in rearing temperature and resource availability due to variation in aquatic breeding habitats. In this study, plasticity in growth rates, larval mass, larval period, and size at metamorphosis were examined in Rana kukunoris Nikolskii, 1918 under different combinations of temperature and food level. Larval period and larval body mass was sensitive to food level, and varied with temperature. Tadpoles metamorphosed at an older age at low temperature than those reared at warm temperature. Food level was a significant affect on larval period at low temperature, but not at warm temperature. Mass was heavier for tadpoles reared at low temperatures than those reared at warm temperatures. The effect of food level depended on temperature, because larvae reared at low temperature that were offered a high food level achieved a larger size than larvae offered a low food level, but this did not occur at warm temperature. Therefore, we suggest that high food availability at low temperature prolonged developmental periods, thus larvae are larger as metamorphs than those reared at warm temperatures. 相似文献