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181.
Environmental Management -  相似文献   
182.
试论高校图书馆的隐性教育   总被引:2,自引:0,他引:2  
本文说明了隐性教育的概念, 指出了高校图书馆隐性教育的功能, 并从教育主体的自主性、教育内容的素质性、教育方位的开放性、教育方式的潜隐性、教育评价的非程序性以及教育管理的预期性等六个方面论述了高校图书馆隐性教育的特性, 最后提出了深化物质性隐性教育、行为性隐性教育以及制度性隐性教育等深化高校图书馆隐性教育的三大途径.  相似文献   
183.
    
Nondestructive and rapid methods for estimating methane emissions from paddy fields are helpful in indentifying options for emission mitigation, both at global and local scales. However, few studies have used an approach of vegetation indices for estimating methane emissions in paddy fields from ground‐based hyperspectral data. Therefore, this study systematically analyzed the quantitative relationship of methane emissions from rice fields to hyperspectral vegetation indices based on hyperspectral reflectance data of rice canopy. A field experiment was designed with two nighttime warming levels, that is, nighttime warming and control (ambient temperature), and two irrigation levels, that is, flooding (control, with 5 cm depth of water layer) and wetting (water saving irrigation, without water layer). Results showed that the newly developed three‐band index (R1139 − R960)/(R1139 + R960 − 2R944) (Rλ is the reflectance value at wavelength λ) was recommended as the optimal index for monitoring methane emission from paddy field, generated coefficients of determination, root mean square error, and residual prediction deviation values between the measured and predicted values of 0.687, 1.424 mg m−2 h−1, and 1.83, respectively. This study provides a theoretical basis and technical support for methane emissions assessment in paddy fields based on vegetation indices. © 2020 Society of Chemical Industry and John Wiley & Sons, Ltd.  相似文献   
184.
    
Environmental Chemistry Letters - The worldwide demand for clean water is rising worldwide, yet wastewater decontamination is actually limited by the presence of refractory organic and inorganic...  相似文献   
185.
中国排污权交易的法制建设探讨——以浙江省为例   总被引:1,自引:0,他引:1  
分析了浙江省排污权交易试点工作中存在的问题,探讨了美国、欧盟等国家和地区的排污权交易法制建设对中国的启示,对国家、地方2个层面进行了排污权交易法制建设的构想。最后,对浙江省排污权交易的法制建设进行了具体设计,并对排污权交易的法制建设提出了可操作性建议。  相似文献   
186.
环境保护是中国的一项基本国策,加强对中学生环境保护宣传教育是学校教育的重要内容。根据中学生的特点,并结合教学实践,提出了串联法、对比法、调查法和引导法等中学地理教学中开展环境保护教育的途径,有利于提高教学质量和教学效果,进而增强中学生的环境保护意识。  相似文献   
187.

In a previous study, we found that rice-straw biochar degraded and removed hydrophobic organic contaminants (HOCs) through coupled adsorption-biodegradation. However, few studies have determined whether biochar affects HOC isomer degradation and isomer-selective biodegradation or whether biochar can alter HOC isomer features, resulting in changes to HOC isomer residues in water environments. In this study, the effects of biochar at two dosages (0.001 and 0.01 g) on the biodegradation of ten isomers of a typical xenoestrogen of nonylphenol (NP) were evaluated. The results revealed that there were no effects of biochar on the adsorption of NP isomers. However, biochar addition affected the biodegradation of a specific isomer without altering the features of the NP isomers. The treatment of NP isomers with Pseudoxanthomonas sp. yielded degradation ratios ranging from 60.7 to 100%. At 0.001 g biochar treatment, the degradation of eight NP isomers was enhanced (except for NP194 and NP193a+b) due to their bulky structures. The degradation of the ten NP isomers was inhibited when 0.01 g biochar was added. These findings characterized the effects of biochar on NP isomer contaminants and provided basic information for the application of biochar for the remediation of NP isomer contaminants.

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188.
Dichloromethane (DCM, also known as methylene chloride [CH2Cl2]) is often present in industrial waste gas and is a valuable chemical product in the chemical industry. This study addresses the oxidation of airstreams that contain CH2Cl2 by catalytic oxidation in a tubular fixed-bed reactor over perovskite-type oxide catalysts. This work also considers how the concentration of influent CH2Cl2 (Co = 500-1000 ppm), the space velocity (GHSV = 5000-48,000 1/hr), the relative humidity (RH = 10-70%) and the concentration of oxygen (O2 = 5-21%) influence the operational stability and capacity for the removal of CH2Cl2. The surface area of lanthanum (La)-cobalt (Co) composite catalyst was the greatest of the five perovskite-type catalysts prepared in various composites of La, strontium, and Co metal oxides. Approximately 99.5% CH2Cl2 reduction was achieved by the catalytic oxidation over LaCoO3-based perovskite catalyst at 600 degrees C. Furthermore, the effect of the initial concentration and reaction temperature on the removal of CH2Cl2 in the gaseous phase was also monitored. This study also provides information that a higher humidity corresponds to a lower conversion. Carbon dioxide and hydrogen chloride were the two main products of the oxidation process at a relative humidity of 70%.  相似文献   
189.
Chen CT  Wann JK  Lou JY 《Chemosphere》2001,43(3):287-294
To identify anthropogenic sources of pollution, it is useful to compare recent and historical data, yet unfortunately such data are lacking in Taiwan. Thus, we studied the sediments deposited in the remote anoxic, subalpine Great Ghost Lake over a time span of 2600 yrs. Not only could a baseline be established, but also natural variations could be identified. Aeolian Asian dust particles seem to have played a significant role in the flux of 26 elements (Al, As, Ba, Br, Ca, Cd, Ce, Cl, Cr, Cs, Cu, Fe, Ga, K, Mg, Mn, Na, Ni, Pb, Rb, Si, Sr, Ti, V, Zn and Zr) in Great Ghost Lake. The fluxes have generally been higher during dry periods, especially since 1350 AD. On the other hand, local pollution from lead seems to have gained importance since 1945 AD. Recent aeolian fluxes were also calculated based on sediment data, and those results agree with direct measurements obtained in the region.  相似文献   
190.
水分剥夺引起毛萼田菁(Sesbaniarostrata)茎瘤固氮活性的下降;水分剥夺还导致茎瘤类菌体固氮的最适O2分压(pO2)和呼吸强度的下降及茎瘤豆血红蛋白和细胞质可溶性蛋白含量的下降。测定水分剥夺的茎瘤在不同pO2下的固氮活性和茎瘤组织切片的显微观察,支持水分胁迫可使O2扩散阻力增大这一观点。测定不同pO2下离体茎瘤固氮活性以pO2为60%最高;当把茎瘤切碎后,茎瘤皮层的扩散屏障作用降低或失去,最适pO2降至40%,说明O2是茎瘤固氮作用的限制因子。  相似文献   
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