固定床渣油加氢脱金属废催化剂上焦炭结构和组成沿床层变化研究

针对取自中石油某装置不同床层轴向位置的工业固定床渣油加氢脱金属废催化剂,采用元素分析、热重分析、X射线光电子能谱、傅里叶变换红外光谱和核磁共振碳谱等,研究了催化剂上沉积焦炭的结构组成特征参数。结果表明,不同轴向位置废催化剂上的焦炭具有某些共同特征,如相同的碳类型和官能团等,但其结构和组成各不相同。模拟建立了基于各种表征结果的焦炭结构组成模型,并利用可计算核磁共振波谱化学位移和预测核磁共振谱图的gNMR软件对所建立焦炭模型的精确性进行了验证,表明模型与实验结果具有很好的一致性。     

固定床渣油加氢脱金属废催化剂上焦炭结构和组成沿床层变化研究（英文）

针对取自中石油某装置不同床层轴向位置的工业固定床渣油加氢脱金属废催化剂,采用元素分析、热重分析、X射线光电子能谱、傅里叶变换红外光谱和核磁共振碳谱等,研究了催化剂上沉积焦炭的结构组成特征参数。结果表明,不同轴向位置废催化剂上的焦炭具有某些共同特征,如相同的碳类型和官能团等,但其结构和组成各不相同。模拟建立了基于各种表征结果的焦炭结构组成模型,并利用可计算核磁共振波谱化学位移和预测核磁共振谱图的gNMR软件对所建立焦炭模型的精确性进行了验证,表明模型与实验结果具有很好的一致性。     

苯乙烯-马来酸酐共聚物的核磁共振分析

利用^1H NMR、^13C NMR及DEPT(无畸变极化转移增强)核磁共振技术研究了苯乙烯-马来酸酐共聚物(SMA)的序列结构和组成，并比较了几种核磁共振实验技术对分析SMA结果的准确性；实验表明^1H NMR是分析组成的简单、快速而有效的方法，DEPT谱进行序列结构计算准确度较高。     

核磁共振波谱在分析化学领域应用的新进展

发展检测物质的化学组成、结构及其变化的新方法、新技术是分析化学的核心科学问题之一. 波谱分析(光谱、质谱及核磁共振)是分析化学中常用的主要仪器分析手段. 核磁共振能在液态、固态和气态条件下提供复杂体系中分子组成、原子分辨的三维结构、相互作用和动态过程等丰富信息, 在生物分析中发挥着越来越重要的作用. 本文将综合阐述核磁共振技术在生物大分子体系、复杂体系以及与其他分析手段联用的进展情况.     

关于聚皂共聚物组成的核磁共振研究

烷基甲基二烯丙基溴化铵共聚物是一种新型疏水改性的聚皂,应用多种核磁共振分析技术对其结构和共单体的组成进行了定量的讨论.研究结果表明,在测定化学结构和性质上比较接近的共单体组成时,核磁共振方法是一种有效的工具.     

碳-13核磁共振法研究小皮伞多糖结构

采用＾１３Ｃ核磁共振法测定和确定了小皮伞多糖中的大分子葡聚糖,葡甘聚糖等３种多糖的一级结构,这些结果与组成分析和甲基化分析结果是一致的,确定了毫克级直接用＾１３Ｃ核磁共振法分析和检测多糖结构的方法。     

卤代-D,L-苯丙氨酸盐酸盐的合成与表征

以乙酰氨基丙二酸酯和苄卤为原料,经缩合、碱性水解、脱羧和脱乙酰基,合成了一组卤代-D,L-苯丙氨酸盐酸盐,利片j核磁共振谱(1H NMR)和质谱(MS)表征了产物的结构,利用元素分析确定了其组成.     

三氮唑偶联的阿拉伯糖苷化白杨素衍生物的合成与表征

利用点击化学,由三乙酰阿拉伯糖叠氮化物和炔丙基取代白杨素分子通过Cu催化的1,3-环加成反应得到了一种三氮唑阿拉伯糖苷化白杨素衍生物,利用核磁共振光谱、红外光谱、电子轰击质谱对其结构进行了表征,并利用元素分析测定了其组成.结果表明,所得合成产物为目标化合物.     

二茂铁基双酰肼化合物的制备及电化学性质

以二茂铁衍生物为原料合成了3个二茂铁基双酰肼类化合物(1,2,3);利用元素分析、红外光谱、核磁共振谱等分析了标题化合物的组成和结构,采用分光光度计测定了其紫外吸收光谱,利用循环伏安法测定了其电化学性质;并利用量子化学计算得到了1的稳定结构.结果表明,化合物1因酰基活性基团被氧化而在高电位区出现一个不可逆氧化峰;与此同时,其在低电位区出现一个不可逆的还原峰.     

锂/钠离子电池材料的固体核磁共振研究进展

固体核磁共振技术是一种定量分析固体材料结构与组成的强有力手段,结合固体核磁共振和常规x-射线衍射(XRD)、 x-射线吸收谱(XAS)等表征方法可对锂/钠离子电池材料在电化学反应中的结构演化过程进行全面的分析. 例如通过固体核磁共振研究, 可获得不同合成与修饰条件下, 锂/钠离子电池电极和电解质材料体相以及电极/电解质界面层的化学组成、局域结构和离子扩散动力学等信息,为高性能电池材料的设计和研发提供重要的基础数据. 本文结合本课题组的研究工作,综述了近三年来国内外固体核磁共振技术在锂/钠离子电池电极、电解质材料以及固体电解质界面膜（SEI）研究中的应用和进展.     

从核磁共振氢谱推导的重质油氢碳原子摩尔比计算式

通过对炼油厂的催化油浆、重催油浆和催化重焦蜡油核磁共振氢谱中质子归属和重质油结构的假设，推导出计算这3种重质油的氢碳原子摩尔比计算式；结果表明，氢碳原子摩尔比的计算值与实测值非常接近，平均误差仅为3．1％。     

L'analyse qualitative et quantitative des huiles lourdes de goudron par chromatographie gazeuse

A method of gas chromatography is described for the rapid qualitative and quantitative analysis of tar heavy oils: naphthalenic oils, wash oils, anthracenic oils, etc.The apparatus used can be easily constructed in an industrial laboratory. The results are calculated by a very simple method of internal normalization requiring no previous standardization.The composition of various oils, determined by the proposed method, is given.     

离子液体催化改质稠油实验研究

研究了离子液体对稠油黏度、组成和平均分子量的影响。结果表明，离子液体对稠油具有较好的改质降黏作用。稠油经离子液体处理后，其饱和烃、芳香烃、胶质质量分数增加，沥青质质量分数明显下降，从而导致稠油的黏度降低，平均分子量减小。研究结果还表明，过渡金属盐改性离子液体对稠油的改质具有催化作用。     

Adulteration of Essential Oils: A Multitask Issue for Quality Control. Three Case Studies: Lavandula angustifolia Mill., Citrus limon (L.) Osbeck and Melaleuca alternifolia (Maiden & Betche) Cheel

The quality control of essential oils (EO) principally aims at revealing the presence of adulterations and at quantifying compounds that are limited by law by evaluating EO chemical compositions, usually in terms of the normalised relative abundance of selected markers, for comparison to reference values reported in pharmacopoeias and/or international norms. Common adulterations of EO consist of the addition of cheaper EO or synthetic materials. This adulteration can be detected by calculating the percent normalised areas of selected markers or the enantiomeric composition of chiral components. The dilution of the EO with vegetable oils is another type of adulteration. This adulteration is quite devious, as it modifies neither the qualitative composition of the resulting EO nor the marker’s normalised percentage abundance, which is no longer diagnostic, and an absolute quantitative analysis is required. This study aims at verifying the application of the two above approaches (i.e., normalised relative abundance and absolute quantitation) to detect EO adulterations, with examples involving selected commercial EO (lavender, bergamot and tea tree) adulterated with synthetic components, EO of different origin and lower economical values and heavy vegetable oils. The results show that absolute quantitation is necessary to highlight adulteration with heavy vegetable oils, providing that a reference quantitative profile is available.     

Comparison of single-reflection near-infrared and attenuated total reflection mid-infrared spectroscopies to identify and monitor hydrocarbons spilled in the marine environment

The capability of single-reflection near-IR (NIR) spectroscopy to differentiate, characterize and monitor the fate of a set of hydrocarbons spilled in the marine environment was compared with that of multiple-reflection horizontal attenuated total reflection mid-IR (ATR-MIR) spectroscopy. Multivariate pattern recognition techniques [principal component analysis (PCA), multivariate polynomial regression, cluster analysis and potential curves] were applied to unravel the major trends of the weathering processes of four generic types of crude oils and two heavy fuel oils spilled under controlled conditions for almost 4 months. A chemical interpretation of the NIR spectra related the weathering processes and the PCA loadings, which had not already been done in the literature. Weathering for both light and heavy products was characterized by a contrast among the linear aliphatic structures (more volatile and easy to degrade) and the branched and aromatic structures (more recalcitrant). Potential curves were applied to model each product and determine objectively whether unknown samples could be classified correctly. Polynomial regression on the PCA scores was employed to evaluate the time elapsed from the oil spillage to its sampling; this represents a new approach to assess the age of a hydrocarbon lump. In general, NIR spectroscopy yielded good results when light crude oils were studied, whereas ATR-MIR spectroscopy led to satisfactory results for both light and heavy products.     

Determination of metals in heavy oil residues by inductively coupled plasma atomic emission spectroscopy

A method is proposed for the sample preparation of heavy oil residues characterized by viscosity of more than 700 mm²/sec at 100°C to study their elemental composition. It is shown that a wide range of elements can be determined in heavy oil residues by inductively coupled plasma atomic emission spectrometry (IC-AES) when the sample dissolved in an organic solvent is injected into the instrument. The optimal parameters for the determination of metals in heavy oil residues by ICP-AES are selected, including an organic solvent and the method of sample dilution. The results of elemental analysis of heavy residues of oils from Chernigovskoe, Shpakovskoe, and Samarskoe deposits are compared. The developed method for determining metals in heavy oil residues significantly reduces the analysis time and does not require complex sample preparation.     

Composition and chemical variability of leaf oil of Myrtus communis from north-eastern Algeria

The chemical composition of 27 oil samples of Myrtus communis isolated from leaves collected in three locations in north-eastern Algeria was investigated by GC(RI) and 13C NMR spectroscopy. Yields ranged between 0.2-1.2% (w/w). The chemical composition of the oils was largely dominated by monoterpene hydrocarbons, with alpha-pinene (40.5-64.0%), 1,8-cineole (10.9-29.1%) and limonene (6.7-8.2%) being the major compounds. In all the samples, 3,3,5,5,8,8-hexamethyl-7-oxabicyclo[4.3.0]non-1(6)-ene-2,4-dione was identified (0.8-1.5%). The composition is similar to that reported for myrtle oils from Corsica, Sardinia and Tunisia, but differed from that of Moroccan and Spanish myrtle oils.     

Chromatographic and spectroscopic analysis of heavy crude oil mixtures with emphasis in nuclear magnetic resonance spectroscopy: a review

The state of the art in the characterization of heavy crude oil mixtures is presented. This characterization can be done by different techniques, such as gas chromatography (GC), high performance liquid chromatography (HPLC), thin layer chromatography (TLC), infrared spectroscopy (IR), Raman spectroscopy, nuclear magnetic resonance (NMR) spectroscopy and mass spectrometry (MS). Nuclear magnetic resonance spectroscopy is the technique of choice due to its capability to provide information on the chemical nature of individual types of hydrogen and carbon atoms in different and complex mixtures of crude oils. The progress made in the interpretation of the NMR spectra with the development of new NMR techniques and different multivariate data analyses could give relevant information about the identification and characterization of hydrocarbons and their physical and chemical properties. These progresses can improve the refining industries operation as a result of the better knowledge on the crude composition that is fed in the refining process, as well as in the prediction of better operating conditions to obtain refined products with desired specifications and in quantities desirable to meet the market demands. The improvement in the refining operation conditions is reflected in economical benefits.     

Thermal investigation of heavy crude oil by simultaneous TG–DSC–FTIR and EDXRF

Present study investigates thermal behavior of two heavy crude oils with different °API values by simultaneous thermogravimetry–differential scanning calorimetry–fourier transform infrared spectroscopy (TG–DSC–FTIR), and an evaluation of the chemical element levels present in the oils’ ashes was done by energy dispersive X-ray fluorescence spectrometry. TG and DSC curves were obtained for two samples in nitrogen atmosphere. Among all inorganic components evaluated, the highest concentration in the two oils was SO₃. Thus this study may contribute to a better understanding of the thermal behavior of heavy crude oils and their composition.     

A simple methodology for the determination of fatty acid composition in edible oils through 1H NMR spectroscopy

A simple methodology for the determination of the fatty acid composition of edible oils through ¹H NMR is proposed. The method is based on the fact that all fatty acid chains are esterified to a common moiety, glycerol, and the quantification is done directly in the ¹H NMR spectra through the relationship between the areas of a characteristic signal of each fatty acid and a signal of the glycerol moiety, without the use of mathematical equations. The methodology was successfully applied to determine the fatty acid composition of several edible oils, with equivalent results to those given by the AOAC Official method by gas chromatography. Its main advantages are simplicity and the lack of need for sample pre‐treatment such as derivatization or extraction. Copyright © 2010 John Wiley & Sons, Ltd.