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141.
利用红外气体箱式法(Infrared Gas Analyze,IRGA),于2008年8月晴天对福州市马尼拉草坪(Zoysia matrel-la)的生态系统CO2净交换(NEE)和环境因子进行观测,阐明NEE及其组分的昼夜动态变化特征和影响因子。马尼拉草坪NEE的昼夜变化呈现为单峰型曲线,昼间其变化规律较强,夜间呈波动状态。NEE(取绝对值)最大值出现在10:00,最小值出现在16:00左右。太阳辐射、腔室内空气相对湿度和气温与NEE的相关性均为极显著(p<0.01),太阳辐射、腔室内空气相对湿度和5cm土壤温度共同解释NEE速率昼夜变异的89.30%。太阳辐射和腔室内空气相对湿度是影响草坪生态系统CO2净交换量日动态的主导环境因子;其中,太阳辐射可以单独解释NEE速率昼夜变化的79.70%,腔室内空气相对湿度可以单独解释NEE速率昼夜变化的50.40%;夏季晴天草坪生态系统在日尺度上表现为净吸收,平均CO2净交换速率为-4.11μmol/(m2.s)(负值表示吸收),平均日总通量为-0.18 mol/(m2.d)。 相似文献
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143.
As a result of the changes that occur during their use, used engine oils tend to differ in chemical and physical composition from a virgin oil. In general recycled oils have: much higher water and sediment levels than virgin oil; relatively higher concentrations of organic compounds (oxidation products); and relatively higher levels of metals such as Fe, Cd, Cr, Pb, etc. Therefore, the aim of this work was to investigate, assess and to observe, by means of the physical and the chemical properties of the oils, atomic absorption (AA), inductive couple plasma (ICP) and Fourier transform infrared (FTIR) analyses the extent of the differences occurring between the virgin and recycled oil. In important part of this work was also the development of analytical techniques based on the use of FTIR spectroscopy; in relation to the rapid analysis of lubricants; in particular for the differentiation of virgin and recycled oil. The results obtained were expected to be useful for differentiation purposes, providing information on whether the metal concentrations and oxidation products could be an appropriate feature for differentiating a particular oil sample from the others. This work is categorized into a two-step procedure. Firstly, an evaluation of a typical FTIR spectrum of an engine oil sample (mono- and multigrade) is presented. The broad feature centered at 1716 cm(-1) is due to the presence of carbonyl containing degradation products of oil. A band observed at 1732, 1169, 1154 and 1270 cm(-1) assigned to the polymethacrylate stretching vibrations, allows the determination of viscosity modifier and pour point depressant additives. The observed differences in the specific spectral bands (1732, 1169, 1154 and 1270 and 1716 cm(-1)) are investigated and discussed. Secondly, an analytical technique for the measurement of the levels of the wear metals is also applied. 相似文献
144.
J.M. Tseng C.Y. Kuo M.Y. Liu C.M. Shu 《Process Safety and Environmental Protection》2008,86(6):415-420
A large amount of hazardous materials and equipment has been extensively employed to produce useful chemicals for our daily lives, but many serious accidents, such as fires, explosions, toxic releases, and so on, that harm human beings and impact the environment have occurred during preparation, operation, and transportation of these chemicals. On 17 May 2007, a toxic release from a boiler explosion in a chemical firm triggered a large amount of xylene (7 ton), isopropanol (8 ton), phosphorus trichloride (44.7 ton), and dimethyl formamide (DMF) (1.37 ton) to be released to the atmosphere with total damages of 2000 m2 level ground. Through concerted efforts from the Yunlin Emergency Response Information Center (YERIC), sponsored by the Environmental Protection Administration (EPA) of Taiwan and other government sectors, this accident was eventually well controlled after 37 h with 107 people being involved in the rescue action. This study could be applied to lessen the degree of hazard for relevant accidents with an emergency response plan (ERP), and, via Fourier transform infrared (FTIR) spectroscopy and photo ionization detector (PID) the toxic concentrations of airborne chemicals that occurred in the industrial area could be analyzed. 相似文献
145.
活性炭氯乙烷防护时间是用于表征活性炭对难吸附有机物的物理吸附性能。本文对活性炭吸附法测定氯乙烷浓度进行了试验,试验表明,测浓管使用的最佳时间是20-40min。针对活性炭吸附法的不足.本文提出了使用红外光谱技术检测氯乙烷浓度,研究表明,红外光谱仪检测氯乙烷浓度是现实可行的。 相似文献
146.
石化企业设备密封点泄漏检测技术研究 总被引:5,自引:0,他引:5
介绍了国内外泄漏检测技术研究现状及发展趋势.利用专业的泄漏检测仪器设备,依据泄漏检测工作流程,对某石化企业进行了全面的泄漏检测.泄漏检测数据统计分析结果表明,企业密封点的外漏比较严重,内漏较轻;加氢装置、油品车间、气分装置、延迟焦化、重整加氢车间和聚丙烯装置密封点泄漏比较严重;采样口、排凝口、调节阀、阀门、阀杆、火嘴、长明灯和法兰泄漏较为严重;红外热像技术在设备密封点气体泄漏检测方面功能强大,应用前景广阔.同时对检测到的泄漏点和问题给企业提出了建议和措施. 相似文献
147.
煤层自燃火灾的自燃火源位置的精确探测是防灭火的关键,也是一项世界性难题。近年来,应用红外技术探测煤层隐蔽火源位置已成为一个热点,通过红外技术定性和定量研究松散煤体升温过程中红外辐射特征变化及影响因素,掌握松散煤体内部热量传递规律,对于利用红外成像技术探测井下煤层自燃隐蔽火源具有重要的参考价值。本文采用在松散煤体中加线状热源,保持热源位置不变,改变热源温度,当温度场达到稳定时用红外热像仪采集表面照片的方法,研究松散煤体表面温度与热源温度的对应关系。结果表明热源上方为高温区域,近似椭圆状,随着热源温度的升高,高温区域不断扩大,表面温度t与热源温度T、像素坐标χ满足关系式。 相似文献
148.
149.
滇池优势挺水植物茭草和芦苇降解过程中DOM释放特征研究 总被引:7,自引:4,他引:3
利用室内分解模拟实验,研究了滇池外海优势挺水植物茭草和芦苇(成熟期)的叶在水环境中降解过程,分析了其释放于水体中水溶性有机质(DOM)浓度和化学结构变化特征.结果表明,植物分解可造成上覆水pH值升高,茭草和芦苇分解过程中上覆水中DOM浓度的变化趋势基本一致.两种植物上覆水中水溶性有机碳(DOC)和水溶性有机氮(DON)的浓度均在8h达到最大值,水溶性有机磷(DOP)的浓度在24 h达到最大值.同时,茭草和芦苇残体内DOM释放强度和速率的变化趋势也基本一致.两种植物DOC、DON和DOP的释放强度和速率都在8 h达到最大,且8 h的释放强度、释放速率、释放比例依次为DOC>DON>DOP.另外,茭草和芦苇分解过程中DOM结构变化分析表明上覆水紫外吸收光谱中SUVA254值先升高再降低,傅里叶红外光谱中—OH特征峰消失,三维荧光光谱中类腐殖酸单位有机碳荧光强度增强. 相似文献
150.
Xiangyun Zhong Shiyong Wu Yang Liu Zhenning Zhao Yaru Zhang Jinfeng Bai Jun Xu Bai Xi 《环境科学学报(英文版)》2013,(S1):S186-S189
The evolvement of morphology and structure of the coal with different metamorphic degrees during coking process in the vertical furnace was investigated by infrared Image detector. Moreover, the temperature distribution in the radial direction and the crack formation were also studied in heating process. The results show that the amount of crack and the shrinkage level of char decrease with the coal rank rising. In addition, the initial temperature of crack formation for char increases with the coal rank rising. 相似文献