软聚氯乙烯塑料的气味分析研究

采用气相色谱-质谱法(GC-MS)对3种软聚氯乙(烯S-PVC)试样的挥发性有机物进行了测试,分析了产生气味的物质。结果表明:试样产生的挥发性有机物为烃类化合物、醇和醛、酯等羰基化合物,产生气味的化合物主要是羰基化合物;添加抗氧剂可阻止增塑剂和其他烃类的氧化,减少S-PVC塑料气味的产生。     

气相色谱-质谱联用法测定软聚氯乙烯塑料的挥发性气体

采用气相色谱-质谱联用法,定性测定了软聚氯乙烯塑料（S-PVC）产生的挥发性气体。结果显示：软聚氯乙烯产生的挥发性气体主要为烃类化合物、醇和醛、酯等羰基化合物,产生气味的化合物是醇和羰基化合物,这些物质可由助剂带入或在塑料加工过程中热氧降解产生。     

香味化学中的双功能团概念

到目前为止,非酶褐变反应或称Maillard反应所产生的芳香化合物,可算是在分子结构与香气之间有明显关系的那类香味化合物的一部分。早先,Hodge假定焦糖气味是一类具特殊分子结构所具有的特征,这类分子具有一种平面状烯醇一羰基亚结构的环状二羰基化合物。在这种结构中可以形成一个氢键。典型的例子是麦芽酚(1)和异麦芽酚(2)。在吡哺型的麦芽酚(1)中之α一二酮亚结构含有一个互变异构体,基氢键位于五元环中,而在β一二羰基异麦芽酚(2)中氢键则是六元环的一部分。     

用DNPH—uV法跟踪聚乙烯薄膜光氧化的微量羰基生成

前言聚乙烯也和其他烃类聚合物一样,在热和光氧化过程中必然伴随有羰基化合物的生成,其量随聚合物氧化程度的加深而增大。因此,利用可跟踪这类化合物的生成动力学的方法,就有可能成为研究和表征聚合物氧化稳定性的一种有效手段。目前,文献中在这一方面已报导的方法有:透射红外光谱法(下称IR法)、衰减全反射或内反射光谱法、荧光分析法、通过试样与N,N-二甲基对苯二胺反应的可见和紫外光谱法、     

不同加工方式对水产品挥发性风味物质影响的研究现状

风味物质分为挥发性气味化合物和非挥发性滋味化合物,其中挥发性化合物是水产品的重要风味特征,而加工方式对水产品挥发性化合物的产生影响显著。本文在对醛类、醇类、酮类、烃类及酯类等挥发性风味物质进行分类叙述的基础上,对不同加工条件下水产品挥发性风味形成的研究进展进行综述,有助于理解水产品挥发性成分的形成机制,为水产品加工业和水产品风味研究提供参考。     

环境大气羰基化合物气粒分配研究进展

羰基化合物是大气中很重要的一类中间化合物,对于大气中臭氧及二次有机气溶胶生成有重要的促进作用.同时,羰基化合物同时存在于气态及颗粒态中,其气粒分配行为对区域大气复合污染乃至全球气候变化等方面都具有重要意义.文章对羰基化合物的分析方法进行了文献总结,并归纳了羰基化合物的实验研究和外场观测.针对目前已有研究存在的不足,进一...     

关于吖啶氮氧化物与烃、醇、酮等之间的光化夺氢反应中的自由基的研究

有关吖啶及其某些衍生物在亲核加成反应中生成的各种自由基或离子基,曾由J.W.Happ等人予以研究,吖啶本身与某些化合物之间的光化夺氢反应也曾被研究过,而吖啶氮氧化物及其衍生物与烃类等化合物之间的光化夺氢反应研究,则尚未见文献报导。我们用吖啶氮氧化物、9-氯代吖啶氮氧化物和9-氰基吖啶氮氧化物分别与包括环烯烃、芳烃、烷烃、醇及羰基化物在内的15种化合物进行光化学反应,用ESR技术检出了很强而又相当稳定的氮氧自由基信号。     

金属催化羰基化合物还原偶联反应的研究进展

羰基化合物还原偶联反应是形成碳一碳键最有效的方法之一,在有机合成中占有重要地位。羰基化合物还原偶联通常由羰基化合物与相应的金属试剂或金属络合物作用而实现,一般遵循单电子转移历程。本文综述了近年来金属钛、钐、铬等在羰基化合物还原偶联反应中应用的新进展。     

硼氢化钠固相还原反应的研究

通过硼氢化钠在固相条件下还原羰基化合物的研究,探索出硼氢化钠在固相条件下还原反应的规律：硼氢化钠在固相条件下,对孤立的羰基还原几乎是定量的,而对共轭的羰基化合物不起反应.     

几种羰基化合物的有机光化学反应研究及应用

分别从分子间吸氢反应、Norrish I型光化学反应、NorrishⅡ型光化学反应、羰基化合物与烯烃的加成反应以及(γ±n)-氢的羰基化合物的光化学重排反应对羰基化合物的有机光化学反应进行简单阐述,并介绍呋喃类、α-二羰基化合物、醛甾酮类等羰基化合物光化学反应的合成工艺及应用。     

塑料与煤低温共焦化的液体产物性质分析

利用GC -MS考察了不同种类塑料 (PDPE ,PP ,PPVC)单独热解及与八一焦煤低温共焦化焦油的组成。结果表明 :添加HDPE、PP使煤焦油中脂肪烃的相对收率提高 ,焦油中脂肪烃的含量明显增加和轻质化 ,可作为加氢精制汽油的原料 ;而PPVC则使脂肪烃和芳香化合物的相对收率均增加 .塑料与煤共焦化过程中同时存在物理和化学协同作用 ,减少了二次反应的机会 ,增加了焦油收率 ,同时促进了焦油中芳香化合物的甲基化 .     

艾叶浸膏挥发性成分及其热裂解产物的全二维气相色谱飞行时间质谱分析

应用全二维气相色谱飞行时间质谱分析了艾叶浸膏的挥发性成分,共检测到210种物质,鉴定出65种匹配度较高的物质,主要为萜烯类物质及其氧化物。应用热失重技术(TG)分析了艾叶浸膏的热失重行为,TG曲线显示艾叶浸膏主要失重区域在145～643℃,其中,145～465℃主要是挥发性及半挥发性物质的挥发,而在465～643℃发生复杂裂解反应。通过热裂解技术分析了艾叶浸膏在不同温度下的裂解产物,结果表明,艾叶浸膏中的挥发性成分包括萜烯类、醇类、脂肪烃类在300℃以下主要是通过蒸馏作用直接转移,而随着裂解温度升高至600～900℃,产生了呋喃等增香物质,同时也生成了羰基化合物、萘、茚等有害物质。     

Regulated and non-regulated pollutants emitted from two aliphatic and a commercial diesel fuel

Two synthetic aliphatic fuels and a commercial one were used on a Diesel vehicle to study the impact on exhaust regulated and non-regulated emissions. The two aliphatic fuels decrease hydrocarbons (HC), carbon monoxide (CO) and particulate matter (PM) emissions comparing to the reference fuel (commercial fuel), but they slightly increase nitrogen oxides (NO_x) emissions. Total particle number and particle size distribution are almost the same for the three fuels used on the New European Driving Cycle (NEDC), however some differences are observed on steady speeds. The two aliphatic fuels decrease the emission of particulate sulphates, of nitrous oxide (N₂O), of carbonyl compounds and methane (CH₄) comparing to reference fuel. Carbon dioxide (CO₂) emissions of the three fuels are similar.     

Neuere Untersuchungen der nicht-glyceridischen Bestandteile von Pflanzenfetten

Recent Studies on the Non-Glyceridic Constituents of Vegetable Fats The authors give a comprehensive review on the non-glyceridic constituents of numerous vegetable fats with special reference to the research work in “Stazione Sperimentale per le Industrie degli Oli e dei Grassi” since about 15 years. Initially, the research was concentrated on olive oil, owing to its great economic significance for Italy and other mediterranean countries; later on, the studies were extended to other vegetable oils. A large number of substance classes were found and identified, which include aliphatic and aromatic hydrocarbons, aliphatic alcohols, terpenic alcohols and their esters, sterols and their esters as well as methyl sterols. Exact identification of these minor constituents required development of special techniques for separation, detection and identification, which are discussed individually. Furthermore, substances occurring in the olive are reported, which attract or repel the olive fly (dacus olivae). Some of these substances have odour and taste, such as aldehydes, aliphatic esters, hydrocarbons and furans, whose structures were elucidated by mass spectrometry. This work might be of interest with respect to measures for pest control.     

Quantitative determination of shale oil compounds by gas chromatography-mass spectrometry-selected ion monitoring

The chemical compounds present in a retort oil sample from an Israeli oil shale and their relative amounts were determined using the selected ion monitoring technique. Quantitative determination of the compounds present showed that the data obtained from whole shale and its subfractions produced by solvent extraction could be correlated. It was concluded that detailed structural results may be obtained from whole shale oil samples without the need to separate the shale oil into its subfractions. The shale oil contained 18% aliphatic long-chain hydrocarbons; the remaining identified portion consisted of aromatic, hydroaromatic, thiophenic furanic, phenolic and pyridinic compounds.     

Cathodic crossed hydrocoupling XIII. Synthetic aspect of the cathodic crossed hydrocoupling reaction of aliphatic carbonyl compounds with electrophiles in aqueous sulfuric acid

For the purpose of organic electrosynthesis, the cathodic crossed hydrocoupling of aliphatic carbonyl compounds with some electrophiles was investigated. When mixtures of carbonyl compounds (such as ketone and aldehyde) and electrophiles (such as activated olefin, pyridine, and cyanamino compound) were electrolysed with various kinds of cathodes in aqueous sulfuric acid, these compounds were coupled reductively to give many useful products in the field of synthetic organic chemistry. In most of the couples of carbonyl compounds and electrophiles, the reduction potentials of the formers were more positive than those of the latters under the electrolysis condition. The yield, current efficiency, and selectivity of products depended on electrolytic conditions, especially cathode material.     

东胜煤有机溶剂分级萃取物的GC/MS分析研究

用气相色谱/质谱联用技术测定了东胜煤有机溶剂萃取物的化学组成，对其化学成分及化合物分布特征进行了研究。结果表明，萃取物主要由烷烃，芳烃和衍生物三种成分组成，其中烷烃主要是正构烷烃；芳烃是萃取物最主要的成分，以萘系，蒽系，菲系，芴系和芘系的0-3烷基取代物为主，和几种高丰度的5-6环稠环芳烃；衍生物主要是多环芳香族含硫化合物，还有一种煤中首次发现的4-氨基-9-芴酮，含氧化合物仅检测到几种。     

Hydrocarbons and other weakly polar unsaponifiables in some vegetable oils

The hydrocarbon fractions obtained from sunflower, olive, soybean, rapeseed and pumpkin seed oils by fractionation of unsaponifiable matter were composed of n-paraffins, isoprenoidal polyolefins, squalene, diterpene and triterpene hydrocarbons and compounds with oxygen. Iso-, anteiso- and other branched hydrocarbons were not identified in any of investigated oils. Possible compounds with oxygen are aliphatic and alicyclic ketones, conjugated steroid ketones, esters and lactones. The differences in the hydrocarbon fractions of investigated oils suggest they may be used for characterization.