不同吸附材料在卷烟降焦减害中的应用

嘴棒吸附技术是卷烟降焦减害方法的一个重要研究及应用领域。本文重点对纳米材料、生物材料、分子筛等在卷烟降焦减害方面的研究及应用进展进行了综述。     

气相色谱-质谱测定无叶假木贼低极性成分

采用气相色谱 -质谱测定无叶假木贼低极性化学成分 ,分离鉴定了 12个化合物 ,它们是萘类与类化合物。     

天登烟挥发性香气成分的聚类分析

为更为系统的了解天登烟的品质特点,采用同时蒸馏萃取-气相色谱/质谱法分析了烟叶样品中挥发性香气成分,并结合DSP软件对18个烟叶样品中13个成分峰按欧式距离类平均法进行了聚类分析。结果表明,各天登烟样品可以有效地聚为一类,特别是2003年的样品差异非常小,进一步说明,天登烟自身的香气特征风格突出,在烟草主要特征香气成分含量与组成方面同国产香料烟与烤烟较为接近,而与白肋烟、晒黄烟之间的差异均较大。     

Principal Components plots for exploratory investigation of reactions using ultraviolet-visible spectroscopy: application to the formation of benzophenone phenylhydrazone

The use of Principal Components plots in the exploratory investigation of reactions monitored by UV-Vis spectroscopy is described. The effects of different types of pre-processing (raw, mean-centred, and standardised) are illustrated. Four types of plot (scores versus time, loadings versus wavelength, scores versus scores, and loadings versus loadings) are considered. The approach is used to investigate the reaction between phenylhydrazine and benzophenone to give a hydrazone. Observable deviations from ideal behaviour indicate differential crystallisation of the product, and the presence of small quantities of an intermediate during the reaction. Additional information about the reaction is gained by comparing selected components from several batches. PCA is easily performed at- or on-line, and the information gained can be used to help decide upon a suitable harder model for further analysis.     

THE INFLUENCE OF PEG MOLECULAR WEIGHT ON MORPHOLOGIES AND PROPERTIES OF PVDF ASYMMETRIC MEMBRANES

The preparation and properties of asymmetric poly(vinyldiene fluoride)(PVDF)membranes are described in this study.Membranes were prepared from a casting solution of PVDF,N,N-dimethylacetamide(DMAc)solvent and water- soluble poly(ethylene glycol)(PEG)additives by immersing them in water as coagulant medium.Experiments showed that when PEG molecular weight increased,the changes in the resultant membranes' morphologies and properties showed a transition point at PEG6000.This indicated that PEG with a relati...     

改进的PLS-NIR光谱法非破坏定量分析Norvasc药片

本文用改进的偏最小二乘法(PLS)解析Norvasc药片的近红外(NIR)漫反射光谱,实现了对其中的有效成分苯磺酸氨氯地平的精确的非破坏定量分析.用样品的主成分得分趋势图选择PLS的最佳主成分数.分别讨论了最佳波长范围以及NIR原始光谱、NIR一阶导数光谱、NIR二阶导数光谱对测定结果的影响.用HPLC法的测定结果作标准,苯磺酸氨氯地平预测值的相对误差RE(%)＜2.53%,可以满足Norvasc药片实际生产中的质量控制要求.     

ICF靶丸内燃料的气液两相组分组成分析

 在质量守恒的基础上,运用拉乌尔定律和道尔顿分压定律,对以摩尔分数比为3∶3∶4比例充入到ICF靶丸内的氘气、氚气和氘化氚三元系的热核燃料,在工作温度为22,24,26,28和30 K下处于相平衡时气液两相的组分组成进行了分析讨论。结果显示:工作温度为22 K时,随着充气压强从1 MPa增大到5 MPa,液层中氘气的摩尔分数从0.251增大到0.290,氚气的摩尔分数从0.350减小到0.310;气泡中氘气的摩尔分数从0.322增大到0.365,氚气的摩尔分数从0.278减小到0.241。充气压强为5 MPa时,随着工作温度从22 K提高到30 K,液层中氘气摩尔分数从0.290减小到0.261,氚气的摩尔分数从0.309增大到0.341;气泡中氘气的摩尔分数从0.365减小到0.302,氚气的摩尔分数从0.241增大到0.298。     

Principal Components – Based Techniques in Voltammetric Determination of Caffeic,Syringic and Vanillic Acids

It was demonstrated that Principal Components Analysis and Principal Components Regression support qualitative and quantitative investigation of three‐component synthetic samples containing micromolar concentration of caffeic acid (CA), syringic acid (SA) and vanillic acid (VA), in various proportions. The first, second and third PCs enable modelling of relationships and distinction of objects of different composition. Optimized and validated multivariate calibration models, implemented on the basis of the samples selected with the help of 3‐level full factorial design, effectively support simultaneous determination of the considered analytes. Obtained RMSEP was no higher than 0.23 μm for CA, 0.17 μm for SA and 0.21 μm for VA, in relation to the concentration of 1.9 to 21.4 μm of each compound. Recovery between 90–108% for considered analytes, determined in synthetic wine solution, was additional verification of calibration model. Application of automatic baseline correction was extensively studied.     

玉米秸秆组分近红外漫反射光谱(NIRS)测定方法的建立

玉米秸秆是我国产量最大的秸秆生物质资源,但目前还没有快速高效的组分分析方法,本研究利用傅里叶变换近红外漫反射光谱 (NIRS) 技术,采用偏最小二乘法(PLS),在国内首次建立了NIRS测定玉米秸秆中灰分、半纤维素、纤维素、Klason木质素、酸不溶灰分和水分含量的校正模型,该模型稳定,适合不同地区、不同品种的玉米秸秆及其不同部位。实验结果表明,采用一阶导数+Karl Norris滤波预处理,谱区在4 100～7 500 cm-1,能得到理想的预测模型。该模型对玉米秸秆各组分的交叉验证均方差(RMSECV)范围为0.090 3～1.45,预测误差(RMSEP)范围为0.256 9%～2.581 9%,预测相关系数≥0.871 1。该研究对加速我国秸秆生物质的工业转化具有重要意义。     

X射线荧光光谱及拉曼光谱法研究五谷营养成分

采用X射线荧光光谱分析法(XRF)和激光拉曼光谱法(Raman),测定了小米、玉米、黄米、大米和小麦5种常用主食(五谷)中营养成分及钾、镁、钙、铁、锌、锰、铝、铜等多种微量元紊的含量.X射线荧光光谱分析法测量结果表明,五谷中所含微量元素非常丰富且种类基本相同,但各元素含量存在很大差异.5种谷类中K元素含量均为最高,含量...