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861.
Sana Ullah Xuejun Guo Xiaoyan Luo Xiangyuan Zhang Siwen Leng Na Ma Palwasha Faiz 《Frontiers of Environmental Science & Engineering》2020,14(5):89
862.
This article reports a novel way to synthesize carbon nanotubes and Cu/ZnO nanoparticles using metal hyperaccumulator plants.
Metal hyperaccumulator plants are traditionally used for phytoremediation to clean soil polluted by toxic metals. However,
the transfer of toxic metals in plant shoots and leaves is an environmental issue because animals and other living organisms
feeding on plants will transfer the metals to the ecosystem. Therefore, we suggest that hyperaccumulator plants could be used
to synthesize nanoparticles. Here, Brassica juncea L., a Cu-hyperaccumulator plant, was collected around a copper mine and used as a raw chemical to produce carbon nanotubes
and Cu/ZnO nanoparticles. The chlorophyll in shoots of B. juncea plants was ethanol extracted to yield chlorophyllin. Cu and Zn were extracted by HNO3 to form Cu/Zn(NO3)2. The chlorophyllin reacted with Cu/Zn(NO3)2 to form Cu/Zn chlorophyllin. Cu/ZnO nanoparticles were synthesized by direct precipitation of Cu/Zn chlorophyllin with NaOH
and ethanol. The vascular bundles in B. juncea plants, which have been purified and carbonized by HNO3, were rapidly heated to about 400°C and then they were cooled to room temperature to obtain carbon nanotubes. Results indicate
that the outer diameter of carbon nanotubes was around 80 nm. Cu/ZnO nanoparticles have a Cu0.05Zn0.95O composition, and had a diameter of about 97 nm. Our study not only inspires the search for a new strategy on the synthesis
of nanostructure from renewable natural products, but also breaks through the traditional and limited ideas about the reuse
of metals by hyperaccumulator plants. 相似文献
863.
Chen Xiang Zhou Weiqi Luo Guoping Luo Pei Chen Zhi 《Environmental science and pollution research international》2020,27(30):37581-37591
Environmental Science and Pollution Research - Diatoms have been proven to be good indicators of natural stream conditions, but little is known about the seasonal variability of diatom communities... 相似文献
864.
865.
We studied the energy and economic flow of six types of homegardens in Sanjia village, SW China. Our study showed that the energy input of six types of homegardens averaged 99.11-175.65 x 1010J/ha, the energy output was 102.30-159.83 x 1010J/ha and the ratio of input/output ranged between 1:0.880-1:1.416. The ratios of input to output of home-gardens that prioritized cultivation of crops were higher than for homegardens that prioritized animal husbandry or other economic activities. The economic ratio of input/ output of six types of homegardens varied between 1:0.997-1:1.376 and the economic output ranged between 2480.0-10131.5 RMB/yr. We concluded that the homegarden systems of Sanjia village are high in the input and output of energy and cash flow, and can provide a basis for designing models of farm economy in rural subtropical areas. 相似文献
866.
Guangyin Chen Zheng Zheng Shiguan Yang Caixia Fang Xingxing Zou Yan Luo 《Waste management (New York, N.Y.)》2010,30(10):1834-1840
Anaerobic co-digestion of corn stalk and vermicompost (VC) as well as mono-digestion of corn stalk were investigated. Batch mono-digestion experiments were performed at 35 ± 1 °C and initial total solid loading (TSL) ranged from 1.2% to 6.0%. Batch co-digestion experiments were performed at 35 ± 1 °C and initial TSL of 6% with VC proportions ranged from 20% to 80% of total solid (TS). For mono-digestion of corn stalk, a maximum methane yield of 217.60 ± 13.87 mL/g TSadded was obtained at initial TSL of 4.8%, and acidification was found at initial TSL of 6.0% with the lowest pH value of 5.10 on day 4. Co-digestion improved the methane yields by 4.42–58.61% via enhancing volatile fatty acids (VFAs) concentration and pH value compared with mono-digestion of corn stalk. The maximum biogas yield of 410.30 ± 11.01 mL/g TSadded and methane yield of 259.35 ± 13.85 mL/g TSadded were obtained for 40% VC addition. Structure analysis by X-ray diffractometry (XRD) showed that the lowest crystallinity of 35.04 of digested corn stalk was obtained from co-digestion with 40% VC, which decreased 29.4% compared to 49.6 obtained from un-treated corn stalk. It is concluded that co-digestion with VC is beneficial for improving biodigestibility and methane yield from corn stalk. 相似文献
867.
本文主要介绍国家标准GB/T28409—2012的制订背景以及防护鞋(靴)的选择、使用和维护指南,并提出标准实施的建议。 相似文献
868.
869.
870.
罗国兵 《中国环境管理干部学院学报》2013,(3):9-12,51
在水质检测工作中,质量控制方法是确保检测数据准确的一种重要手段。当前水质检测实验室中常用的质控手段有盲样考核、平行测定、加标回收、比对试验、期间核查、相关性分析与质量监督六类,通过分析比较这些质控手段在分析检测中的差异及其对检测结果的影响,为提升水质检测工作质量,出具科学、公正的检测报告提供保障。 相似文献