植物添加剂降低卷烟烟气稠环芳烃的研究进展

卷烟烟气中的稠环芳烃是一种高致癌性有害物质,对人体有很大的毒害作用.文章简单地介绍了烟气中稠环芳烃的形成、性质及对人体的危害,并详细综述了植物添加剂降低卷烟烟气稠环芳烃的研究进展.降低清除卷烟中稠环芳烃含量及其机理的研究是一个长期且复杂的难题,至今国际上尚未彻底解决.研究开发无毒无副作用的高效针对性的新型植物添加剂,对缓解吸烟与健康的矛盾具有重要的意义,其发展前景广阔.     

柠檬酸钾对选择性降低卷烟烟气中稠环芳烃释放量的研究

为研究柠檬酸钾对主流烟气中稠环芳烃的选择性降低效果,采用湿法添加将不同量的柠檬酸钾溶液加到烟丝中,研究了不同添加量对焦油和烟气中稠环芳烃(PAHs)的影响。结果表明:①柠檬酸钾添加量在2‰~15‰范围内,随着添加量的增加,焦油含量呈下降趋势;②苯并[α]蒽、、苯并[α]芘的含量随着添加量的增加而减少,当柠檬酸钾添加量为8‰时,3种稠环芳烃的含量达到最低值,降低率分别达到25.89%,29.71%,23.76%,随后随着添加量增加,含量也增加。     

卷烟烟气中多环芳烃的同时测定

在优化卷烟烟气试样前处理技术的基础上,确定了6种多环芳烃分离的最佳条件和测定的最佳荧光激发、发射波长,并进行波长程序编程,采用高效液相色谱编程荧光法（HPLC-FLD）建立了一种同时测定卷烟烟气中6种多环芳烃的分析方法。各多环芳烃在所测定的含量范围内有良好的线性关系,方法的最低检出限可达到0.4 ng/mL,回收率均在87%以上。并利用该方法对国产卷烟样品进行了分析。     

β-环糊精对卷烟主流烟气中有害成分的吸附研究

研究了β-环糊精对卷烟主流烟气中几类有害成分的吸附能力,以及吸附效果与吸附质物性的关系。将β-环糊精添加于卷烟滤嘴中,使用行业标准和文献方法对卷烟主流烟气中的有害成分进行检测,结果表明:β-环糊精对主流烟气中的酚类、多环芳烃和喹啉有较好的吸附效果,添加量为30 mg时,平均吸附率分别为58. 11%、35. 83%和61. 34%。对于挥发及半挥发性有机化合物,吸附率与吸附质沸点呈较强的正相关,对于酚类和多环芳烃化合物,吸附率与吸附质沸点呈较强的负相关,对于多环芳烃化合物,吸附率与吸附质分子半径呈较强的负相关。     

(EU)No 1272/2013条例对橡胶行业的影响及应对措施

正多环芳烃(Polycyclic aromatic hydrocar bons,简称PAHs)是指分子中含有两个或两个以上苯环的碳氢化合物,可分为芳香稠环型及芳香非稠环型,是最早被认识的化学致癌物,也是目前发现数量最多,环境分布最广,与人类关系最密切的一类致癌物。多环芳烃可经过皮肤或肺吸收引起皮肤癌、肺癌、胃癌等,有证据表明空气中苯并芘与皮肤癌、肺癌有明显正相关性。美国、德国、中国等众多国家已经出台法规或标准控制和监管多环芳烃对人类健康的危害。     

气相色谱-质谱法测定卷烟主流烟气中的多环芳烃

通过优化前处理条件,建立了卷烟主流烟气中16种多环芳烃的检测方法,并用该方法检测了8个牌号的卷烟样品。以环己烷超声萃取剑桥滤片中捕集的多环芳烃,固相萃取提纯,旋蒸浓缩,气相色谱质谱联用仪进行检测,方法的最佳超声萃取时间为20 min,固相萃取溶液流速不应超过2 mL/min,各化合物的检出限在0. 05 ng/cig至0. 18 ng/cig,以相对标准偏差表示的重复性不大于7. 66%,加标回收率在87. 15%至110. 73%,适用于卷烟主流烟气中多环芳烃的分析。     

燃烧条件对燃煤过程多环芳烃生成特征的影响

采用小型管式实验炉,通过控制燃烧温度、过剩空气量研究了不同燃烧条件对燃煤过程16种多环芳烃(PAHs)生成与分布的影响。实验结果表明:燃煤烟气中PAHs生成量随燃烧温度的升高而增加,灰渣中PAHs生成量随燃烧温度的升高呈先增加后减少的规律;随着过剩空气系数(α)的增大,烟气中PAHs生成量逐渐减少,灰渣中PAHs生成量呈先明显减少而后基本不变的趋势;PAHs组成的分布表现出三、四环含量突出的特征;烟气中PAHs毒性当量(TEQ)远大于灰渣;在保证煤完全燃烧的情况下,综合考虑对烟气和灰渣中PAHs生成总量以及毒性当量TEQ的控制,燃烧条件为温度为850℃,α=1.57时,PAHs对环境的影响较小。     

稠环芳烃加氢饱和催化剂研究进展

受共振能、空间位阻和竞争吸附等方面的影响,稠环芳烃末环的吸附活化是其加氢饱和反应的重点和难点之一。本文系统综述了稠环芳烃加氢饱和反应特点及各类稠环芳烃加氢饱和催化剂。分析表明,稠环芳烃吸附活化与其分子自身的属性和催化剂的性质密切相关,调控催化剂中活性金属的电子状态可有效促进稠环芳烃分子的吸附活化。针对常见稠环芳烃加氢饱和催化剂,本文分类阐述了各类稠环芳烃加氢饱和催化剂的活性相结构、活性位点数量和活性金属电子密度的调控方法。分析指出,提高活性组分的分散度和形成活性金属的缺电子状态能够提升催化剂的加氢活性,可通过调节载体的酸性和添加助剂等方法实现。     

液相色谱法检测卷烟烟气中部分成分的研究进展

基于液相色谱法分析效率高、灵敏度高、操作容易、应用广泛等特点,综述了液相色谱法检测卷烟烟气中部分成分[如醛酮类化合物、多环芳烃、酚类化合物、烟草特有亚硝胺化合物(TSNAs)]的研究进展,并比较分析了不同检测方法的优缺点,为深入研究卷烟烟气中的部分成分提供参考。     

稠环芳烃裂化研究进展

稠环芳烃物种含有大量的芳烃资源,由于苯环间的共轭效应,难以将其直接转化。随着原油芳烃含量的逐年增高,在工业规模如何有效地处理稠环芳烃备受关注。对稠环芳烃的加氢裂化和催化裂化反应机理进行总结对比,并通过介绍裂化催化剂的研究进展为稠环芳烃的催化裂化拓展新思路。     

Phase-mineral and chemical composition of coal fly ashes as a basis for their multicomponent utilization. 4. Characterization of heavy concentrates and improved fly ash residues

The phase-mineral and chemical composition of heavy concentrates (HCc) and improved fly ash residues (IFAs) recovered from five fly ashes (FAs) produced in four large Spanish thermo-electric power stations was characterized. The HCs were separated by sink-float separation in bromoform, while the IFAs are residues after the isolation of ceramic cenosphere, salt, magnetic, char and heavy concentrates. The HCs recovered are in the range 0.02–0.28% and their phase-mineral composition (in decreasing order of significance) commonly includes aluminosilicate glass, hematite, magnetite, larnite, quartz, periclase, mullite, corundum, lime, char, melilite, rutile, plagioclase, wollastonite, ferrian spinel, and anhydrite. Numerous accessory minerals of Ba, Ce, Cl, Cr, Cu, F, Fe, La, Mn, P, Pb, Th, Ti, Y, and Zr, are also typical components of HCs. These fractions are enriched in As, Ca, Cr, Cu, Gd, Mg, Mn, Mo, Fe, Ni, Pb, S, Se, Ti, V, Zn, and Zr in comparison with the FAs. The IFAs isolated are in the range 71.5–97.1% and their phase-mineral composition (in decresing order of significance) normally includes aluminosilicate glass, mullite, quartz, char, kaolinite, plagioclase, cristobalite, wollastonite, hematite, anhydrite, K-feldspar, melilite, and corundum. The contents of most elements in IFAs are similar to FAs as Ag, Ba, Cl, Cs, Ge, Mo, S, Sb, and Sc are significantly depleted in these residues. The IFAs have an improved composition in comparison with the FAs because they are: more homogeneous and finer-grained products; abundant in pozzolan and inert constituents; and depleted in harmful components. Some genetic features, properties, possible environmental concern, and potential utilization directions related to the HCs and IFAs are described. A basis for the advanced, multicomponent, wasteless, and environmentally safety utilization of various FAs is also discussed.     

应用ICP-MS同时测定矿泉水中22种微量金属

研究结果表明应用ICP-MS可以同时测定饮用天然矿泉水中的Li、Be、B、Al、Ti、V、Cr、Mn、Co、Ni、Cu、Zn、Ge、As、Se、Sr、Mo、Ag、Cd、Sb、Ba、Pb、等微量金属元素.ICP-MS法具有快速、准确、处理简单、干扰少等优点.     

微波消解-ICP-OES法测定黑芝麻中的18种矿质元素

采用HNO3/H2O2湿法微波消解制样,利用全谱直读电感耦合等离子原子发射光谱法(ICP-OES),全面详细地分析测定了黑芝麻中的矿质元素,共检出Ca、P、S、Mg、K、Al、Si、Fe、Na、Zn、Se、Sr、Cu、Mn、Ba、B、Ti、Cr等18种矿质元素,RSD值在1.21%～10.1%,其中13种元素在5%以内。黑芝麻中所含人体常量元素Ca、P、S、Mg、K、Na等的质量分数分别为1.79%,1.08%,0.59%,0.43%,0.41%和0.009 1%;微量元素Fe、Zn、Se、Cu、Mn、B、Cr、Sr、Si、Al等的含量分别为18.6,4.55,3.87,1.74,1.62,0.91,3.21,78.8,125.8 mg/100 g,未检出Pb、Hg、Cd、As以及Ni、Co、Mo等元素。     

一种具有混合侧链的苯并菲类盘状液晶材料的合成及其液晶性能的表征

本研究采用邻苯二酚、溴代正戊烷和乙酰氯为原料合成了以苯并菲为基元的盘状液晶化合物2,6,10-三乙酯基-3,7,11-三戊氧基苯并菲,化合物的结构采用核磁手段1HNMR进行鉴定。采用偏光显微镜POM和DSC手段对该种化合物的相行为进行了研究,并且与合成过程中的中间体2,3,6,7,10,11-六戊氧基苯并菲的相行为进行了比较。     

Ecological Risk Assessment of Polycyclic Aromatic Hydrocarbons in Surface Sediments from the Upper Reach of Huaihe River

Based on the available toxicity data and the concentrations of polycyclic aromatic hydrocarbons (PAHs) in 16 surface sediments from upper reach of Huaihe River, overlapping areas of probability density curves and margin of safety (MOS₁₀) were used to estimate the ecological risk of eight PAHs to aquatic organisms. The results indicated that the overlapping areas of Pyr, Nap, Fla, Ant, Phe, Ace, BaP, and Flu were 0.38, 0.29, 0.16, 0.11, 0.07, 0.03, 0.03, and 0.01, respectively. The risk of Pyr was the highest while that of Flu was the lowest. The overlapping area of ΣPAH₈ was 0.72, higher than that of any individual PAHs due to their joint effect. The calculated MOS₁₀ for Nap, Ace, Flu, Phe, Ant, Fla, Pyr, and BaP were 6.86, 5.42, 19.0, 2.72, 0.93, 0.75, 0.03, and 63.0, respectively. The probabilities of Nap, Ace, Flu, Phe, and BaP surpassing the 10th percentile value of the toxicity data were 0.07%, 0.30%, 0.05%, 1.97%, and 0.01%, respectively, suggesting minimal risk to aquatic organisms. However, the probabilities of Ant, Fla, and Pyr exceeding this value were 11.3%, 12.9%, and 64.8%, indicating potential risks. Among the individual PAHs, the ecological risk from Pyr was the highest, followed by Fla, Ant, Phe, Ace, Nap, Flu, and BaP. Additionally, the combined ecological risk of ΣPAH₈ in the upper reach of Huaihe River was significantly higher than that of any individual PAH alone, which the probabilities of ∑PAH₈ in excess of the 10th percentile of the toxicity data were 99.4%.     

芦丁配合物的合成研究进展

芦丁及其衍生物具有广泛的药理活性。芦丁具有完整的大盯键共轭体系,强配位氧原子与合适的空间构型,可与金属离子螯合成稳定的环状配合物。研究表明：这些配合物有些具有明显的生物活性,有些药理作用显著。到目前为止,国内外共合成了31种芦丁金属配合物,其中主族元素有5个：Mg、Al、Ga、Sn和Bi;副族元素有12个：Cr、Mn、Fe、Co、Ni、Cu、Zn、Y、Mo、Cd、Pt和Au;稀土元素有14个：La、Ce、Pr、Nd、Sm、Eu、Gd、Tb、Dy、Ho、Er、Tm、Yb、Lu等。     

抗菌防腐剂（Ⅰ）—抗菌防腐剂的历史、定义与分类

简要回顾了抗菌防腐剂的发展历程,进一步明确了杀菌剂,抑菌剂,抗菌剂,防腐剂,防霉剂,消毒剂,杀生剂,保鲜剂,抗生素的概念。同时,结合抗菌防腐剂的发展在对抗菌防腐剂按无机物,有机物和天然物分类的基础上,进一步又按化学结构和官能团将抗菌剂分为有机金属,有机卤代物,醇,酚,醚,醛,酮,醌,酸,酯,含氮类,含硫类,有机磷,有机砷类以及杂环类等。     

Electrospun Nanofibers: Materials,Synthesis Parameters,and Their Role in Sensing Applications

Since the last decade, electrospinning is garnering more attention in the scientific research community, industries, applications like sensing (glucose, H₂O₂, dopamine, ascorbic acid, uric acid, neurotransmitter, etc.), biomedical applications (wound dressing, wound healing, skin, nerve, bone tissue engineering, and drug delivery systems), water treatment, energy harvesting, and storage applications. This review paper provides a brief overview of the electrospinning method, history of the electrospinning, factors affecting the electrospun nanofibers, and their morphology with different materials and composites (metals, metal oxides, 2D material, polymers and copolymers, carbon-based materials, etc.) used in the electrospinning technique with optical spinning parameters. Moreover, this paper deliberates the application of electrospun nanofibers and fibrous mats for sensing (electrochemical, optical, fluorescence, colorimetric, mechanical, photoelectric, mass sensitive change, resistive, ultrasensitive, etc.) in most illustrative representations. In the end, the challenges, opportunities of the electrospun nanofibers, and new direction for future progress are also discussed.     

合成环己酮乙二醇缩酮的催化剂研究进展

评述了近年来国内采用甲烷磺酸盐、对甲苯磺酸、氨基磺酸、强酸性阳离子交换树脂、磺化聚氯乙烯、六水三氯化铁、二水氯化亚锡、五水四氯化锡、四水氯化锰、硫酸铜、水合硫酸铁、十二水合硫酸铁铵、硫酸钛、四水硫酸锆、氯化锆、四水硫酸高铈、水合硝酸镧、活性炭固载硫酸镧、铌酸、树脂固载Lewis酸、壳聚糖硫酸盐、一水硫酸氢钠、碘、磷酸二氢钠、固体超强酸、杂多酸、分子筛和维生素C等固体酸催化合成环己酮乙二醇缩酮的实验结果。研究结果表明,固体酸能够代替硫酸作为合成环己酮乙二醇缩酮反应的催化剂。     

氯碱下游产品建设投资分析(续2)

介绍了20种氯碱下游产品--氯甲苯、氯乙酸、环氧氯丙烷、氯化苄、环氧丙烷、聚偏氯乙烯树脂、氯化聚氯乙烯树脂、氯化聚乙烯、甲基氯硅烷、三氯氢硅、氯化法钛白粉、三氯化磷、4,4'-二苯基甲烷二异氰酸酯、1,4-丁二醇、苯胺、环己酮、气相法白炭黑、甲基异丁基酮、对氨基苯酚、水合肼的市场前景、技术来源与建设投资.