近红外光谱法快速同时测定烟用香精中常用溶剂含量

基于近红外光谱技术建立了烟用香精中水、乙醇、1,2-丙二醇、丙三醇4种组分含量的预测模型，并对模型进行了验证和评价。结果表明，所建预测模型可同时快速对样品中的水、乙醇、1,2-丙二醇、丙三醇含量进行预测，采用Savitzky-Golay滤波平滑+一阶导数光谱预处理，模型的校正集相关系数（R2）均大于0.985，校正均方根误差（RMSEC）分别为0.884、0.644、1.720、0.849。将模型的预测值与气相色谱-热导检测器（GC-TCD）法测定结果相比较，二者结果无显著性差异（P>0.05），利用预测值建立了质量控制模型，当显著水平为5%条件下，该模型对异常样品和正常样品的正确判别率均为100%。可见，近红外光谱技术能对烟用香精常用溶剂进行无损、快速、高效的同时分析，并可用于烟用香精生产与应用过程中的质量监测。     

基于FT-NIR技术的烟用香精香料品质控制技术研究

烟用香精香料是卷烟工业企业的核心技术,对其品质的综合控制颇为重要。使用近红外光谱结合马氏距离法和相似度分析法对固态香精样品、液态香精样品质量进行分析,建立了烟用香精的马氏距离和相似度匹配的品质控制模型,所建立的模型能够准确鉴别出不良样品。用建立的马氏距离模型,对不同厂家投标样品和批次检验样品进行马氏距离计算并作判定,马氏距离≤6的样品判定为合格香精样品,反之则判定为不合格香精样品。建立相似度匹配类模型,对不同厂家投标样品和批次检验样品进行相似度计算并作判定,匹配值≥95%的样品判定为合格香精样品,反之则判定为不合格香精样品。通过对招标样品、制备香精样品、香原料入库样品的质量稳定性研究表明,基于FT-NIR光谱技术,结合化学计量学能对液态、膏状及固态香精的分类及质量稳定性进行评估,既能快速识别样品的种类,又能监测样品的质量波动情况,在实际生产中,应用于烟用香精质量控制具有较好的实用价值。     

用香味成分分析法研究烟用香精的质量控制

把烟用香精进行同时蒸馏萃取、气相色谱/质谱联用仪(GC/MS)鉴定、气相色谱仪(GC)定量分析,建立了分离分析烟用香精香味成分的方法,选择十几种香味成分作为特征峰,用以监控香精的质量波动情况。对选择的香味成分特征峰进行了重复性实验以及不同批次香精的稳定性实验。结果显示,重复性实验的相对标准偏差小于不同批次香精的质量波动;经过对烟用香精进行不同温度的耐热性实验,经相似度检验,进一步确认了通过分析香精中的香味成分,可达到监控质量的目的。     

GC/MS法建立烟用香精指纹图谱研究

采用超声辅助液液萃取法(ULLE)对8个不同批次的烟用HMT香精成分进行提取,用GC/MS对其进行定性定量分析,建立了该香精的GC/MS指纹图谱的研究方法,目的在于为烟用香精质量控制提供一种方便、快捷、可靠的分析手段。结果表明:ULLE方法具有操作简便、快速、节能、萃取效率高、重现性好等特点,适合于烟用香精成分的提取。8个批次的HMT香精的指纹图谱稳定性好,相似度高,具有很强的特征性和唯一性。通过该香精指纹图谱的建立,对日后进厂的HMT香精进行质量控制提供了依据。     

热重分析法在烟用香精仿香中的应用

为了研究仿配香精与目标香精的相似程度,对香精样品进行热失重分析,根据热失重曲线对仿配香精与目标香精的一致性进行评价。本文以目标香精及4个仿配香精样品为研究对象,在优化后的热失重条件下进行程序升温,获得特定条件下的热失重曲线,结合GC-MS成分分析和感官评价结果,比较了仿配香精与目标香精的相似程度。结果表明：（1）热重曲线的差异能够反映出香精内在组成的差异;（2）GC-MS谱图一致并不代表样品成分组成完全一致,热重法是对烟用香精成分一致性判定的一个重要技术补充;（3）热重法可以用于烟用香精的仿配相似程度判定。     

烟用香精的超高压液相色谱指纹图谱分析

为了控制烟用香精质量,利用超高压液相色谱,建立了香精的UPLC指纹图谱,并应用夹角余弦和欧式距离法计算香精的相似度。结果表明：6批次的香精指纹图谱稳定性好,相似度高,具有很强的特征性和唯一性,夹角余弦法和欧氏距离法计算简单,二者结合能够全面考察香精的质量。利用超高压液相色谱建立的色谱指纹图谱能快速、全面、综合、准确地反映烟用香精的质量状况,可以成为烟用香精质量控制的有效手段。     

气相色谱法测定烟用香精中的乙醇、1,2-丙二醇和丙三醇

为了准确测定烟用香精中溶剂的含量,以1,4-丁二醇为内标建立了检测烟用香精中乙醇、1,2-丙二醇和丙三醇的气相色谱法,采用该方法测定了30个烟用香精样品。结果表明:该方法的检出限和定量限范围在0.019～0.088和0.063～0.293g/L之间;回收率在97.5%～101.6%之间;相对标准偏差(RSD)为0.61%～0.89%。所测样品中均检出1,2-丙二醇,均未检出丙三醇;13个样品中检测出乙醇。该方法前处理简单、灵敏度高、定性定量准确,适用于烟用香精中乙醇、1,2-丙二醇和丙三醇的定性定量分析。     

烟用香精质量稳定性的评价及统计过程控制

通过对不同牌号烟用香精的相对密度、折光指数、酸值及挥发性成分总量进行分析测量,运用方差分析、聚类分析、偏差指标分析等工具对实测数据开展综合评价,借用控制图对产品质量进行精确监视。结果表明,方差分析可判断不同年份间指标差异的显著性,并建立显著性差异综合表;偏差指标分析可表征质量特性偏离中心值的程度;聚类分析较为明晰直观地显示不同烟用香精之间的相似性;统计控制图则能科学客观地反映产品质量的异常波动。分析人员若将各方法有效结合并加以灵活应用,可达到相互印证和优势互补的效果,从而为企业加强香精香料的质量控制提供有力保障,为各生产厂家实施质量改进提供参考依据。     

烟用香精的全二维气相色谱-飞行时间质谱定性分析

针对在一维色谱上分离峰太少或色谱图中有明显重叠峰的烟用香精,采用全二维气相色谱-飞行时间质谱（GC×GC-TOFMS）对烟用香精进行了定性分析,优化分析条件,并与一维色谱分析结果进行比较。最后,比较了不同分析结果所得化学成分和品吸结果之间的对应关系。结果表明,GC×GC-TOFMS比一维气相色谱/质谱（GC/MS）具有更强的分离能力,可定性的组分明显多于一维GC/MS,并且更符合该香精的评吸结果。这种分析方法有利于更全面地认识香精的化学成分,更准确地认识香精的组成与功能之间的关系。为增强加香配方研究的科学性、提高调香工作的效率提供有力的支持。     

微波消解-电感耦合等离子体质谱法测试烟用香精及料液中6项重金属

采用硝酸-过氧化氢消解体系,微波消解烟用香精及料液,后采用电感耦合等离子体质谱仪对铅、镉、铬、镍、砷、汞进行测试。该方法各元素相对标准偏差1.3%～8.5%,检出限0.091～0.305 ug/L,加标回收率82.4%～103.5%。该方法简单、快速、灵敏性、准确度好,适用于烟用香精及料液中6种痕量重金属元素的定量分析。     

Insect antifeedant properties of anthranoids from the genusVismia

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.     

Direct observation of freeze-thaw instability of latex coatings via high pressure freezing and cryogenic SEM

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.     

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.     

Methyl 2,4,6-decatrienoates Attract Stink Bugs and Tachinid Parasitoids

Halyomorpha halys (Stål) (Pentatomidae), called the brown marmorated stink bug (BMSB), is a newly invasive species in the eastern USA that is rapidly spreading from the original point of establishment in Allentown, PA. In its native range, the BMSB is reportedly attracted to methyl (E,E,Z)-2,4,6-decatrienoate, the male-produced pheromone of another pentatomid common in eastern Asia, Plautia stali Scott. In North America, Thyanta spp. are the only pentatomids known to produce methyl 2,4,6-decatrienoate [the (E,Z,Z)-isomer] as part of their pheromones. Methyl 2,4,6-decatrienoates were field-tested in Maryland to monitor the spread of the BMSB and to explore the possibility that Thyanta spp. are an alternate host for parasitic tachinid flies that use stink bug pheromones as host-finding kairomones. Here we report the first captures of adult and nymph BMSBs in traps baited with methyl (E,E,Z)-2,4,6-decatrienoate in central Maryland and present data verifying that the tachinid, Euclytia flava (Townsend), exploits methyl (E,Z,Z)-2,4,6-decatrienoate as a kairomone. We also report the unexpected finding that various isomers of methyl 2,4,6-decatrienoate attract Acrosternum hilare (Say), although this bug apparently does not produce methyl decatrienoates. Other stink bugs and tachinids native to North America were also attracted to methyl 2,4,6-decatrienoates. These data indicate there are Heteroptera in North America in addition to Thyanta spp. that probably use methyl 2,4,6-decatrienoates as pheromones. The evidence that some pentatomids exploit the pheromones of other true bugs as kairomones to find food or to congregate as a passive defense against tachinid parasitism is discussed.     

2005～2006年国外塑料工业进展

收集了2005年7月～2006年6月国外塑料工业的相关资料，介绍了2005—2006年国外塑料工业的发展情况。提供了世界塑料产量、消费量及全球各类树脂生产量以及各国塑料制品的进出口情况。作为对比，介绍了中国塑料的生产情况。按通用热塑性树脂（聚乙烯、聚丙烯、聚苯乙烯、聚氯乙烯、ABS树脂）、工程塑料（聚酰胺、聚碳酸酯、聚甲醛、热塑性聚酯、聚苯醚）、通用热固性树脂（酚醛、聚氨酯、不饱和树脂、环氧树脂）、特种工程塑料（聚苯硫醚、液晶聚合物、聚醚醚酮）的品种顺序，对树脂的产量、消费量、供需状况及合成工艺、产品开发、树脂品种的延伸及应用的扩展作了详细的介绍。     

2007～2008年世界塑料工业进展

收集了2007年7月～2008年6月世界塑料工业的相关资料,介绍了2007～2008年国外塑料工业的发展情况,提供了世界塑料产量、消费量及全球各类树脂的需求量及产能情况.按通用热塑性树脂(聚乙烯、聚丙烯、聚苯乙烯、聚氯乙烯、ABS树脂)、工程塑料(尼龙、聚碳酸酯、聚甲醛、热塑性聚酯、聚苯醚)、特种工程塑料(聚苯·硫醚、液晶聚合物、聚醚醚酮)、通用热固性树脂(酚醛、聚氨酯、不饱和聚酯树脂、环氧树脂)不同品种的顺序,对树脂的产量、消费量、供需状况及合成工艺、产品应用开发、树脂品种的延伸及应用的进一步扩展等技术作了详细介绍.