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添加造纸法再造烟叶是卷烟降焦的重要手段,但再造烟叶烟气中CO含量相对较高,降低造纸法再造烟叶烟气中的CO含量刻不容缓。研究了Cu和Co等过渡金属氧化物催化剂在降低造纸法再造烟叶烟气中CO含量的催化性能。经过对催化剂的初步筛选,Cu-Mn复合氧化物催化剂表现出最佳的CO催化氧化性能。为进一步提高催化剂的利用效率及催化活性,从两个方面进行深入研究:(1)在再造烟叶制备过程中的不同工艺阶段加入催化剂,结果发现,将催化剂的固体粉末分散在浆料中,有助于得到催化剂分散均匀的再造烟叶,烟气中的去除率为12.8%;(2)将催化剂以不同的形式分散,结果发现,将催化剂前驱体溶液与涂布液混溶是使催化剂均匀分散的最好方式,利用此方式将Cu-Mn催化剂加入再造烟叶中,使CO去除率高达15%。表明过渡金属氧化物催化剂对降低再造烟叶烟气中CO含量表现出良好的催化性能,且催化剂在再造烟叶中的分散性对催化性能有着至关重要的作用。 相似文献
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为了解爆珠破碎对主流烟气中焦油、烟碱、一氧化碳(CO)、水分,以及卷烟物理性能总量、圆周、吸阻、通风的影响,试验制备了3种不同圆周的爆珠卷烟(24.3、20.0、17.0 mm)。结果表明不同圆周卷烟在爆珠捏爆后,抽吸口数、烟支重量、圆周和通风率差别不大,主流烟气焦油、烟碱、CO略有增加,水分增加最为明显,开吸阻和闭吸阻的平均值降低,变异系数增加。爆珠破碎导致吸阻降低可能是烟气常规化学指标增加的原因。此外随着卷烟圆周的减小,爆珠破碎对卷烟物理指标和烟气常规化学指标的影响逐渐降低。该研究为爆珠卷烟产品的设计分析提供参考。 相似文献
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氢氰酸是卷烟烟气中含量较少且具有挥发性毒性的物质,吸烟时会随着口腔进入人体或者挥发到周围的空气中,不但会抑制人体细胞呼吸酶,造成细胞内窒息,对人体健康造成很大的危害,同时对环境安全也会造成一定的影响。介微孔材料具有较大的比表面积、孔容、孔径和材料表面可修饰性,更重要的是多孔材料大多无毒无害、易制备且能选择性的降低卷烟烟气中的有害物质,因此可以作为吸附剂或者载体应用于卷烟滤嘴中,通过物理吸附和化学吸附选择性的降低卷烟烟气中的氢氰酸。综述了几种以不同方式制备的介微孔材料降低卷烟烟气中氢氰酸的效果,并展望了介微孔材料对于降低卷烟烟气中氢氰酸释放量的研究前景。 相似文献
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通过电镜、比表面积及微孔物理吸附仪对木材颗粒表面形貌和比表面积进行表征。在卷烟对比实验中,研究木材颗粒复合滤棒和未采用木材颗粒醋纤滤棒的吸附性能。结果表明,木材颗粒表面呈鱼鳞状,具有介孔吸附材料特性;木材颗粒复合滤嘴可以降低卷烟主流烟气中的焦油和7种有害物质,对比未使用木材颗粒复合滤嘴下降幅度分别达到了焦油8.57%,CO 2.17%,B(a)P 22.22%,NNK 4.50%,巴豆醛3.49%,HCN 20.37%,氨离子3.77%和苯酚21.16%;木材颗粒复合滤嘴可以提升烟气浓度,增加烟香丰富性和改善舒适性。 相似文献
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It is well established that a wide range of drugs of abuse acutely boost the signaling of the sympathetic nervous system and the hypothalamic–pituitary–adrenal (HPA) axis, where norepinephrine and epinephrine are major output molecules. This stimulatory effect is accompanied by such symptoms as elevated heart rate and blood pressure, more rapid breathing, increased body temperature and sweating, and pupillary dilation, as well as the intoxicating or euphoric subjective properties of the drug. While many drugs of abuse are thought to achieve their intoxicating effects by modulating the monoaminergic neurotransmitter systems (i.e., serotonin, norepinephrine, dopamine) by binding to these receptors or otherwise affecting their synaptic signaling, this paper puts forth the hypothesis that many of these drugs are actually acutely converted to catecholamines (dopamine, norepinephrine, epinephrine) in vivo, in addition to transformation to their known metabolites. In this manner, a range of stimulants, opioids, and psychedelics (as well as alcohol) may partially achieve their intoxicating properties, as well as side effects, due to this putative transformation to catecholamines. If this hypothesis is correct, it would alter our understanding of the basic biosynthetic pathways for generating these important signaling molecules, while also modifying our view of the neural substrates underlying substance abuse and dependence, including psychological stress-induced relapse. Importantly, there is a direct way to test the overarching hypothesis: administer (either centrally or peripherally) stable isotope versions of these drugs to model organisms such as rodents (or even to humans) and then use liquid chromatography-mass spectrometry to determine if the labeled drug is converted to labeled catecholamines in brain, blood plasma, or urine samples. 相似文献
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ICP-MS法测定地球化学样品中As、Cr、Ge、V等18种微量痕量元素的研究 总被引:15,自引:0,他引:15
建立了测定地球化学样品中包括As、Cr、Ge、V等18种微量、痕量元素的ICP-MS方法。地化试样用HF-HNO3混酸分解后,以1 1 HNO3溶解干渣。由于制样不使用盐酸,避免了Cl对As、Cr、Ge、V的质谱干扰。用国家一级地球化学标准物质GBW 07309制备溶液优化仪器工作参数,并用于校准。方法测定限(6s)为:0.007~6.4μg/g,精密度(RSD%,n=12)为:29%~9.4%,经过国家一级地球化学标准物质的分析验证,结果与标准值吻合。方法已应用于国土资源调查的试样分析。 相似文献
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M. S. J. Simmonds W. M. Blaney F. Delle Monache M. Marquina Mac-Quhae G. B. Marini Bettolo 《Journal of chemical ecology》1985,11(12):1593-1599
Vismiones and ferruginins, representatives of a new class of lypophilic anthranoids from the genusVismia were found to inhibit feeding in larvae of species ofSpodoptera, Heliothis, and inLocusta migratoria. 相似文献
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Cheng-Le Zhao Shane Porzio Alan Smith Haiyan Ge H. T. Davis L. E. Scriven 《Journal of Coatings Technology and Research》2006,3(2):109-115
Despite its industrial importance, the subject of freeze-thaw (F/T) stability of latex coatings has not been studied extensively.
There is also a lack of fundamental understanding about the process and the mechanisms through which a coating becomes destabilized.
High pressure (2100 bar) freezing fixes the state of water-suspended particles of polymer binder and inorganic pigments without
the growth of ice crystals during freezing that produce artifacts in direct imaging scanning electron microscopy (SEM) of
fracture surfaces of frozen coatings. We show that by incorporating copolymerizable functional monomers, it is possible to
achieve F/T stability in polymer latexes and in low-VOC paints, as judged by the microstructures revealed by the cryogenic
SEM technique. Particle coalescence as well as pigment segregation in F/T unstable systems are visualized. In order to achieve
F/T stability in paints, latex particles must not flocculate and should provide protection to inorganic pigment and extender
particles. Because of the unique capabilities of the cryogenic SEM, we are able to separate the effects of freezing and thawing,
and study the influence of the rate of freezing and thawing on F/T stability. Destabilization can be caused by either freezing
or thawing. A slow freezing process is more detrimental to F/T stability than a fast freezing process; the latter actually
preserves suspension stability during freezing.
Presented at the 82nd Annual Meeting of the Federation of Societies for Coatings Technology, October 27–29, 2004 in Chicago,
IL. Tied for first place in The John A. Gordon Best Paper Competition. 相似文献
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Ethanol and (−)-α-Pinene: Attractant Kairomones for Bark and Ambrosia Beetles in the Southeastern US
In 2002–2004, we examined the flight responses of 49 species of native and exotic bark and ambrosia beetles (Coleoptera: Scolytidae
and Platypodidae) to traps baited with ethanol and/or (−)-α-pinene in the southeastern US. Eight field trials were conducted
in mature pine stands in Alabama, Florida, Georgia, North Carolina, and South Carolina. Funnel traps baited with ethanol lures
(release rate, about 0.6 g/day at 25–28°C) were attractive to ten species of ambrosia beetles (Ambrosiodmus tachygraphus, Anisandrus sayi, Dryoxylon onoharaensum, Monarthrum mali, Xyleborinus saxesenii, Xyleborus affinis, Xyleborus ferrugineus, Xylosandrus compactus, Xylosandrus crassiusculus, and Xylosandrus germanus) and two species of bark beetles (Cryptocarenus heveae and Hypothenemus sp.). Traps baited with (−)-α-pinene lures (release rate, 2–6 g/day at 25–28°C) were attractive to five bark beetle species
(Dendroctonus terebrans, Hylastes porculus, Hylastes salebrosus, Hylastes tenuis, and Ips grandicollis) and one platypodid ambrosia beetle species (Myoplatypus flavicornis). Ethanol enhanced responses of some species (Xyleborus pubescens, H. porculus, H. salebrosus, H. tenuis, and Pityophthorus cariniceps) to traps baited with (−)-α-pinene in some locations. (−)-α-Pinene interrupted the response of some ambrosia beetle species
to traps baited with ethanol, but only the response of D. onoharaensum was interrupted consistently at most locations. Of 23 species of ambrosia beetles captured in our field trials, nine were
exotic and accounted for 70–97% of total catches of ambrosia beetles. Our results provide support for the continued use of
separate traps baited with ethanol alone and ethanol with (−)-α-pinene to detect and monitor common bark and ambrosia beetles
from the southeastern region of the US. 相似文献
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以大分子引发剂氯乙酰化聚苯乙烯微球(PS-acyl-Cl)经原子转移自由基聚合(ATRP)法引发丙烯酰胺(AM)和甲基丙烯酸缩水甘油酯(GMA)单体的共聚接枝,制得一种触角状亲水性环氧载体(PS-acyl-g-P(AM-co-GMA)),再经二乙醇胺(DEA)的环氧基开环胺化反应,得到一种含多个-NCH2CH2OH螯合配基的多齿-五元螯合环的触角状亲水性羟胺树脂(PS-acyl-g-P(AM-co-GMA)-DEA)。将此树脂用于硼吸附研究,结果表明,PS-acyl-g-P(AM-co-GMA)-DEA树脂对硼的吸附满足Langmuir方程,为单分子层吸附;饱和吸附量约为37.7 mg·g-1,且树脂5 min即可达到吸附平衡,与其它已报道的吸硼树脂相比,该树脂具有更高的吸附量和吸硼速率。吸附动力学研究表明,树脂吸附硼的过程主要由颗粒扩散过程控制。重复使用5次后该树脂的吸附量基本不变,解吸率均在90%以上,重复使用性能良好。 相似文献