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81.
内蒙古草原挥发性有机物排放通量的研究 总被引:8,自引:0,他引:8
2002年夏季,利用静态箱方法,对我国内蒙古草原生态系统挥发性有机物的排放进行了首次测量,同时观测了太阳辐射、温湿度等参数.结果表明,异戊二烯是草地挥发性有机物排放中的主要成分.异戊二烯的排放有明显的日变化、逐日变化和季节变化规律.因子分析表明,可见光辐射、温度、水汽含量是影响异戊二烯排放的主要因子,而且可见光辐射是控制其排放过程的最主要因子.根据相关分析,在考虑影响异戊二烯的排放因子时,不仅要考虑通常的影响因子--可见光辐射、温度,还要考虑水汽的作用.箱方法的使用不可避免地造成箱内外太阳辐射、温湿度等的差别,因此,必须考虑修正采样箱对挥发性有机物排放通量带来的影响.2002年夏季,异戊二烯排放通量(C)的最大值为1649.3μg/(m2·h).6、8、9月采样期间异戊二烯排放通量的日平均值分别为886.6、707.0、427.2μg/(m2·h). 相似文献
82.
相变储能光伏太阳能热泵干燥系统的研究 总被引:1,自引:0,他引:1
建立了相变储能光伏太阳能热泵干燥系统实验平台,介绍了系统的运行方式以及太阳能光伏集热蒸发器与直流压缩机的匹配计算,最后对实验数据进行了分析。结果表明,太阳能辐照量为800 W/m~2、光伏集热蒸发器面积为12 m~2的条件下,系统制热功率为10 k W,太阳能光伏集热蒸发器发电量为6.2 k W·h,大于直流压缩机的耗电量,满足供电要求;实验所得系统COP为3.25。相变储能可以解决太阳辐照波动导致的系统运行不稳定问题,具有显著的节能性和环保性。 相似文献
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选取湖南省浏阳市某Cd污染稻田进行田间试验,研究组配改良剂石灰石+海泡石(LS)、基施硅肥及叶面喷施硅肥对Cd污染稻田修复效果,结果表明:(1)基施硅肥90kg/hm2和叶面喷施硅肥(0.2,0.4g/L)对土壤pH值无明显影响,添加LS(2250,4500kg/hm2)的各处理均显著提高土壤pH值(P < 0.05).(2)基施硅肥90kg/hm2分别降低土壤交换态、毒性特征浸出(TCLP)提取态Cd含量20.0%和18.5%,叶面喷施硅肥对土壤Cd两种提取态含量无明显影响,添加LS的各处理(2250,4500kg/hm2)分别使土壤交换态、TCLP提取态Cd含量降低25.8%~49.9%、26.4%~44.5%.(3)3种单一技术措施均能明显降低水稻各部位Cd含量,但降低糙米中Cd含量的效果低于3种技术措施的组合处理;“组配改良剂LS+基施硅肥+叶面喷施硅肥”各处理(JL1F1、JL1F2、JL2F1、JL2F2)使水稻糙米中Cd含量降低25.6%~70.5%.(4)“组配改良剂LS+基施硅肥+叶面喷施硅肥”的组合技术处理能显著降低土壤中Cd的有效性,显著降低水稻各部位中Cd含量,其中JL2F2处理效果最佳,能使对照糙米Cd含量从0.66mg/kg降低到0.19mg/kg,实现中重度Cd污染稻田的水稻安全生产. 相似文献
86.
浅谈海上油井安全阀及其控制系统技术的应用 总被引:1,自引:0,他引:1
针对实际生产条件,为全面推行海上安全环保、节能与清洁生产,在油井上安装了太阳能安全阀控制系统,对油井生产与安全管理起着重要的作用。 相似文献
87.
Chin-Tsan Wang Thangavel Sangeeth Wei-Mon Yan Wen-Tong Chong Lip-Huat Saw Feng Zhao Chung-Ta Chang Chen-Hao Wang 《环境科学学报(英文版)》2019,31(1):163-168
Single-chamber sediment microbial fuel cells(SSMFCs) have received considerable attention nowadays because of their unique dual-functionality of power generation and enhancement of wastewater treatment performance. Thus, scaling up or upgrading SSMFCs for enhanced and efficient performance is a highly crucial task. Therefore, in order to achieve this goal, an innovative physical technique of using interface layers with four different pore sizes embedded in the middle of SSMFCs was utilized in this study.Experimental results showed that the performance of SSMFCs employing an interface layer was improved regardless of the pore size of the interface material, compared to those without such layers. The use of an interface layer resulted in a positive and significant effect on the performance of SSMFCs because of the effective prevention of oxygen diffusion from the cathode to the anode. Nevertheless, when a smaller pore size interface was utilized, better power performance and COD degradation were observed. A maximum power density of 0.032 mW/m~2 and COD degradation of 47.3% were obtained in the case of an interface pore size of 0.28 μm. The findings in this study are of significance to promote the future practical application of SSMFCs in wastewater treatment plants. 相似文献
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Lead (Pb) is a heavy metal, known to induce oxidative stress and produce damage to the antioxidant defence system ultimately leading to cell death. Antioxidants such as epigallocatechin 3-gallate (EGCG), a green tea polyphenol, was shown to play a protective role during Pb-exposure. In this study, human SH-SY5Y neuroblastoma cells were exposed to different concentrations (0.01–10?µM) of Pb for 48?h to determine effects on the viability of cells. It was observed that IC50 was at 5?µM and at this concentration the cells exhibited a significant increase in caspase-3 activity, an indicator of apoptosis at least by 10-fold and the decrease of 59.4% in glutathione (GSH) content. The total cellular prostaglandin-E2 (PGE2) level was found to be elevated at least 10-fold upon Pb exposure. However, the effects of Pb on cells pre-incubated with 50?µM EGCG followed by 5?µM Pb showed 40% inhibition in cell viability, 17.3% decrease in caspase-3 activity, 23% increase in GSH content, and 11.4% fall in PGE2 levels when compared with cells exposed to Pb only. Data suggest that EGCG exerted a significant protection to cell viability in preventing cell death and elevation in levels of GSH in cells exposed to Pb. However, EGCG did not elicit any significant effect on release of PGE2 indicating the nature of EGCG as an effective anti-apoptotic, antioxidant, and anti-inflammatory agent. 相似文献
90.
In the present investigation, the toxicity of mercuric chloride (HgCl2) was evaluated in adult oval cells isolated from rat utilizing the 2-acetylaminofluorene/partial hepatectomy technique. Isolated oval cells were incubated with 5 μM of HgCl2 for 8 hr to elucidate in vitro cytotoxic responses. Recently, autophagic cell death was found in rat hepatocytes in vitro within 30 min of incubation with 5 μM of mercury (Hg) which triggered apoptosis and necroptosis in a time-dependent manner. Nuclear degradation occurred within 30 min of incubation and progressed with time until 8 hr. Apoptosis evidenced by activation of caspase-dependent pathway between 30 min to 8 hr of incubation was mediated via interchange of death domain signaling pathways. Receptor-interacting protein played a positive role to modulate the death domain receptors in the scenario of apoptotic death of oval cells until 6 hr. Autophagic marker proteins ATG12 and LC3B exerted a significant role in triggering apoptosis in 5 μM Hg-treated oval cells. No apparent expression of apoptosis-inducing-factor (AIF) and HMGB1 indicated absence of caspase-independent apoptosis and necrosis in the rat oval cells between 30 min and 8 hr. Thus a low concentration of Hg modulates programmed cell death in adult rat oval cells by altering expression of proteins involved in the molecular mechanisms of cellular functions. 相似文献