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文章分别采用气液微萃取与气固微萃取技术,以对羟基苯甲酸为捕集剂捕集香烟烟气中的羟基自由基。比较了两种技术捕集的效果,结果表明气固微萃取技术捕集效果更佳。此外还分析了香烟过滤嘴对清除烟气自由基的作用。 相似文献
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流光放电等离子体氨法烟气脱硫脱硝技术概述 总被引:3,自引:0,他引:3
等离子体烟气脱硫技术属大气领域的尖端技术,也是国际上的研究热点.它充分利用了等离子体自由基的强氧化性和氨吸收的化学特性实现脱硫脱硝,并副产铵肥.介绍了流光放电脱硫脱硝的原理、中试流程、技术特点等,并与其他烟气脱硫脱硝工艺进行了性能和技术经济比较. 相似文献
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综述自由基对人体健康的影响及目前的预防措施 总被引:3,自引:0,他引:3
自由基是一个不成对电子的原子团,易夺取其他物质的一个电子,而氧是易得电子的元素,在生物体内主要是活性氧自由基在破坏人体健康。在人体正常代谢下自由基有一定的免疫和传递信号的功能,但过量的自由基就会严重影响人的身体健康,引发多种疾病如心脏病、老年痴呆症等。因此降低自由基对人体危害已势在必行,科学家已经发现许多天然抗氧化剂能清除过量的自由基。目前,研究更有效的自由基清除剂已成为当今科学发展的趋势。 相似文献
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文章介绍了水泥工业废气主要污染物对环境及人体健康的影响,对国内现行的国标及地标中特别排放标准进行了统计,对国内公布的地方超低排放限值进行了整理统计,介绍了水泥工业烟气二氧化硫、氮氧化物、及颗粒物的治理技术及应用情况。 相似文献
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火电行业燃煤烟气是SO_2、NO_x和烟尘的主要来源之一,造成的环境污染非常严重,对人体健康和区域经济发展均产生了不良影响。随着《火电厂大气污染物排放标准》和环境保护部《关于执行大气污染物特别排放限值的公告》的实施,对燃煤烟气的脱硫脱硝一体化处理成为各企业亟待解决的难题。文章着重介绍了某火电厂采用脱硫脱硝一体化技术对原烟气处理系统进行改造的情况,改造后烟气中的SO_2、NO_x、烟尘等指标均实现了稳定达标排放。 相似文献
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详细介绍了石油沥青烟气中有毒组分和臭味组分,并对建立石油沥青烟气中有毒组分和臭味组分标准与规范提出一些建议。石油沥青烟气中有毒组分主要为2~6环多环芳烃PAHs,包括苯并[a]蒽、苯并[a]芘、苯并[e]芘类,研究表明芘对人体有致癌作用,并且对神经系统具有毒害作用。石油沥青烟气中臭味组分为含硫和含氮化合物,包括噻吩类和亚砜,同时还含有少量吲哚类含氮恶臭污染物。详细介绍了石油沥青烟气抑制技术中吸附型抑烟剂、氧化型抑烟剂和聚合物抑烟剂的研究现状并对其做出评价,此外对石油沥青抑烟剂研究进行展望。 相似文献
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Korotkova EI Misini B Dorozhko EV Bukkel MV Plotnikov EV Linert W 《International journal of molecular sciences》2011,12(1):401-410
The human body is constantly under attack from free radicals that occur as part of normal cell metabolism, and by exposure to environmental factors such as UV light, cigarette smoke, environmental pollutants and gamma radiation. The resulting “Reactive Oxygen Species” (ROS) circulate freely in the body with access to all organs and tissues, which can have serious repercussions throughout the body. The body possesses a number of mechanisms both to control the production of ROS and to cope with free radicals in order to limit or repair damage to tissues. Overproduction of ROS or insufficient defense mechanisms leads to a dangerous disbalance in the organism. Thereby several pathomechanisms implicated in over 100 human diseases, e.g., cardiovascular disease, cancer, diabetes mellitus, physiological disease, aging, etc., can be induced. Thus, a detailed investigation on the quantity of oxygen radicals, such as hydroxyl radicals (OH•) in human serum blood, and its possible correlation with antioxidant therapy effects, is highly topical. The subject of this study was the influence of schizophrenia on the amount of OH• in human serum blood. The radicals were detected by fluorimetry, using terephthalic acid as a chemical trap. For all experiments the serum blood of healthy people was used as a control group. 相似文献
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《Polycyclic Aromatic Compounds》2013,33(4):429-439
Cigarette smoke contains a large number of chemicals and gaseous compounds including polycyclic aromatic hydrocarbons (PAHs). Due to the importance of PAHs and their health effects in cigarettes, development of systems to analyze PAHs in cigarette smoke may become useful in developing a less harmful product. However, the complexity of cigarette smoke chemistry remains a significant obstacle in its analysis: many cigarette smoke components are produced due to reactions such as decomposition and recombination of cigarette components during the smoking process. Methods to analyze these reactions in real-time are needed. In this article the authors report direct monitoring of pyrene in mainstream smoke using time-gated laser-induced fluorescence (LIF) based on fiber optics. The time-gated detection system could provide a reduced background signal of mainstream smoke when using optimized gate delay and gate width parameters. The results demonstrate the feasibility of direct monitoring of PAHs in mainstream smoke. 相似文献
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为研究非邻苯二甲酸酯类增塑剂在卷烟主流烟气的转移行为,将12种非邻苯酯类增塑剂添加到卷烟烟丝中,利用剑桥滤片捕集卷烟主流烟气,剑桥滤片和烟蒂分别经二氯甲烷萃取后,使用GC/MS/SIM分析各非邻苯酯类增塑剂在主流烟气的转移率和烟蒂的截留率。结果表明:12种非邻苯酯类增塑剂在主流烟气的转移率在7.86%~15.11%之间;12种非邻苯酯类增塑剂在烟蒂中的截留率在18.65%~36.54%之间;非邻苯酯类增塑剂在烟蒂中的截留率明显高于在主流烟气中的转移率,其中己二酸二乙酯在主流烟气中的转移率最低,而在烟蒂中截留率最高。 相似文献
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Four wire coating materials (two of them based on PVC and the two others based on XLPE) were assessed for the irritancy of their smoke, under non-flaming conditions, by using the respiratory depression method, expressed as the RD50. The DIN 53 436 combustion tube was used as the fire model, at a temperature of 550°C (smouldering mode), and the animal model was the mouse. Animals were exposed for 10 min, at concentrations too low to cause lethality. It was found that there was relatively little difference between the irritancy of all four smokes. This was an unexpected result, since it had been predicted that PVC smoke would be much more irritating than XLPE smoke. In fact, the smoke from the PVC compounds had an RD50 roughly in the range of 100–1000 ppm, while the smoke from the XLPE compounds had an RD50 roughly in the range of 10–100 ppm. This means that PVC smoke is somewhat less irritating than XLPE smoke. The components in the smoke of all materials were determined by a combination of continuous gas analysis, ion chromatography and gas chromatography/mass spectrometry, with the objective of understanding the factors causing the irritancy. Hydrogen chloride, one of the major decomposition products of PVC, is also the most important smoke constituent causing irritancy of the smoke. Its irritancy, however, was insufficient, by a considerable margin, to explain the full degree of irritancy found. The RD50 of HCl is, like that of PVC smoke, in the range of 100–1000 ppm. On the other hand, the only compound found in the smoke of XLPE compounds with an RD50 in the same 10–100 ppm range as he overall smoke is methyl vinyl ketone. Unfortunately, the concentration of methyl vinyl ketone was much too low to account for the irritancy levels encountered. Literature data indicate that polyethylene smoke is rich in long-lived free radicals and that PVC smoke does not contain them. Moreover, such free radicals are associated with various illnesses, particularly with respiratory symptoms. Thus, it is speculated that such free radicals could be the cause of the high irritancy of the smoke from the XLPE wire coating materials. 相似文献
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为降低卷烟烟气中有害成分低分子醛酮化合物的含量和研究X型分子筛在卷烟减害中的应用,将13X型分子筛添加到卷烟嘴棒中,分析其对主流烟气中八种低分子醛酮化合物含量的影响。结果显示13X分子筛对低分子醛酮有明显的脱除作用。通过进一步研究13X分子筛对烟气中苯酚和苯并(α)芘的吸附作用,揭示了13X分子筛对低分子醛酮的选择性吸附与其因表面静电引力优先吸附极性物质的特性以及低分子醛酮的低熔沸点密切相关。烟气三项指标分析表明,13X分子筛对烟气中的焦油和烟碱含量影响不大,这有利于保持卷烟的香气。 相似文献
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Cigarette smoke (CS) contains thousands of substances, mainly free radicals that have as a target the polyunsaturated fatty acids (PUFA). Long chain PUFA are produced through elongation and desaturation reactions from their precursors; the desaturation reactions are catalyzed by different enzymes: the conversion of 18:2n-6 (linoleic acid, LA) to 18:3n-6 by Delta6 desaturase, while that of 20:3n-6 to 20:4n-6 by Delta5 desaturase. The aim of this work is to evaluate the effect of serum exposed to cigarette smoke (SE-FBS) on (1) cell viability and proliferation, (2) [1-(14)C] LA conversion and desaturase activities in THP-1 cells, a monocytic cell line. In THP-1, CS inhibits cell proliferation dose-dependently, by producing a modification in the cell cycle with a reduced number of cells in synthesis and mitosis phases at higher concentrations. CS also decreases [1-(14)C] LA conversion to its derivatives in a concentration-dependent manner, inhibiting the activities of Delta6 and mainly Delta5 desaturase. In addition, CS does not modify the incorporation of LA into various lipid classes but it reduces cholesterol synthesis from radiolabelled acetate, and increases free fatty acid, TG and CE levels. In conclusion, CS affects lipid metabolism, inhibiting LA conversion and desaturase activities. CS also shifts the "de novo" lipid synthesis from free cholesterol to TG and CE, where LA is preferentially esterified. 相似文献
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