火棘叶挥发油化学成分的GC-MS分析

采用水蒸气蒸馏法从火棘叶中提取挥发油,利用气相色谱-质谱(GC-MS)联用方法分析火棘叶挥发油化学成分,并以面积归一法测定各成分的相对含量。从火棘叶挥发油中共鉴定出69种化合物,占挥发油总量的80.52%,主要成分为(-)-b-杜松烯(22.62%)、植物醇(19.90%)、二环倍半水芹烯(5.95%)、β-桉叶醇(5.78%)、1,2,3,4,4a,7-六氢-1,6-二甲基-4-(1-甲基乙基)-萘(2.78%)、表圆线藻烯(2.34%)等。     

超声雾化顶空单滴微萃取-气相色谱-质谱法测定果汁中的芳香成分

本文建立了超声雾化顶空单滴微萃取-气相色谱-质谱(GC-MS)联用测定果汁中的β-月桂烯、D-柠檬烯和异戊酸叶醇酯含量的方法。考察了萃取溶剂、萃取时间、富集时间等影响芳香成分萃取效率的因素。在最优的实验条件下,对三种果汁中的芳香成分进行了分析,测得三种果汁中β-月桂烯、D-柠檬烯和异戊酸叶醇酯的含量分别为12.0~488.6μg·mL~(-1)、542.8~1.237×10~4μg·mL~(-1)和0.0470~498.5μg·mL~(-1)。方法的回收率范围为78.5%~110.4%,相对标准偏差为1.3%~4.4%。     

不同产地鱼腥草药材挥发油成分的研究

从定量指纹图谱的角度,结合气相色谱-质谱(GC-MS)联用技术和直观推导式演进特征投影法(HELP)分辨解析重叠色谱峰,并对广东省博罗县、云南省大理市、湖南省长沙县3个不同产地的鱼腥草(Herba Houttuyniae)药材进行比较研究。结果表明,不同产地鱼腥草药材挥发油成分的差异主要体现在物质的相对含量上,其中(-)-4-萜品醇、α-松油醇、桧烯和β-月桂烯等物质含量的差别较大。3个不同产地(-)-4-萜品醇的相对含量分别为0.19%～0.24%、4.47%～4.93%、0.03%～0.07%,α-松油醇的相对含量分别为0.17%～0.27%、0.22%～0.24%、0.07%～0.09%,桧烯的相对含量分别为0.48%～0.64%、25.2%～26.8%、0.07%～0.11%,β-月桂烯的相对含量分别为33.66%～43.36%、10.11%～11.11%、51.23%～55.39%。该研究为规范鱼腥草药材中挥发油类成分在制药和用药的实际应用提供了一些可靠的基础。     

GC-O-MS法对酒花中香气活性成分的分析

采用顶空固相微萃取气相色谱-嗅闻-质谱((HS-SPME-GC-O-MS)联用的方法研究酒花中的香气化合物的组成和风味,并与传统的同时蒸馏萃取、水蒸气蒸馏方法进行比较,定性采用质谱谱库检索结合保留指数进行验证。结果表明:3种方法测得的1号酒花中的香气活性成分存在较大的差异,HS-SPME法最为适合,该法共鉴定出71种成分,占总峰面积质量分数的97.93%,以月桂烯、β-石竹烯为主要成分的萜烯类化合物共22种,其质量分数达88.73%,醇类及酯类质量分数分别为1.98%,3.42%。采用该方法对3个不同的酒花品种定性并嗅闻,能够嗅闻到的香气活性成分共计34种,包括碳氢化合物(包括萜烯)类7种,醇(酚)类11种,酯类10种,酮类2种,未知化合物4种。嗅闻结果表明,在1号、2号、3号3种酒花中分别嗅闻到了26,23,16种香气物质,其中重要的香气活性成分为β-香茅醇、β-石竹烯、里那醇、香叶醇、α-萜品醇、β-香茅醇、橙花醇、橙花椒醇、香叶酸甲酯、辛酸甲酯、乙酸香叶酯等。     

水母雪莲花挥发油的GC-MS分析

采用气相色谱-质谱(GC-MS)联用技术对西藏产水母雪莲花的挥发油化学成分进行分析,共分离鉴定出83种化合物,占挥发油总量的70%以上.其中主要成分有β-芹子烯(6.72%)、斯杷土烯醇(4.74%)、红没药醇(4.10%)和金合欢醇(3.32%)等.     

顶空萃取-气相色谱-质谱法分析马鞭草的挥发油组分

采用顶空萃取-气相色谱-质谱法分离和鉴定马鞭草挥发油化学成分,用归一化法测定其相对含量.鉴定出64个组分,其含量占总挥发油组分峰面积的97.76%.主要成分是乙酸(3.55%)、芳樟醇(4.41%)、反-石竹烯(9.30%)、反-β-金合欢烯(3.99%)、律草烯(5.61%)、α-姜黄烯(8.50%)、十五烷(8.48%)、γ-芹子烯(3.75%)、β-没药烯(5.66%)、β-杜松烯(3.57%).     

气相色谱-质谱法测定艾叶挥发油中化学成分

采用水蒸气蒸馏法提取艾叶的挥发油,用气相色谱-质谱法分离和鉴定挥发油成分,并用归一化法测定其相对含量。共分离出76个组分,鉴定出59种化合物。其含量占总挥发油组分峰面积的94.3%。贵州遵义产艾叶主要挥发油成分及其含量为1,8-桉叶油素(22.19%)、樟脑(10.39%)、绿花白千层醇(6.57%)、蒿醇(4.95%)、L-龙脑(4.88%)、α-松油烯(3.98%)、蒿酮(3.44%)、顺式桧烯水合物(3.36%)、4-松油醇(2.68%)、菊油环酮(2.51%)、β-崖柏酮(2.41%)、1-松油醇(2.32%)和丁香酚(2.26%)等。     

浙江艾蒿和野艾蒿挥发油成分分析研究

用GC/MS进行浙江野艾蒿和艾蒿挥发油成分分析.鉴定出野艾蒿31个化合物,占挥发油含量的83.27%.主要成分为:桉叶素(21.82%)、胡椒烯(10.48%)、β-石竹烯(8.86%)、樟脑(8.50%)、侧柏酮(7.28%).鉴定出艾蒿24种化合物,占挥发油含量的77.70%.主要成分为:异蒿属酮(37.01%)、桉叶素(12.81%)、异蒿属醇(9.30%)等.两种同属植物含有18种相同化合物.     

固相微萃取-气相色谱-质谱法分析香樟籽挥发性成分

采用固相微萃取-气相色谱-质谱法分离和鉴定香樟籽的挥发性成分,用归一化法测定其相对含量。共分离出76种组分,鉴定出47种化合物,其含量占总挥发性成分的97.4%。主要挥发成分为樟脑(57.89%)、柠檬烯(12.68%)、α-蒎烯(4.42%)、莰烯(2.69%)、香橙烯(2.34%)、伞花烃(2.26%)及β-蒎烯(2.12%)。     

气相色谱-质谱技术分析红松松塔挥发性成分

采用水蒸气蒸馏法,对红松松塔挥发性成分进行提取和研究,最佳蒸馏时间5.5 h,挥发油提取率1.28%.利用气相色谱-质谱联用技术对提取的挥发油成分进行分析,共鉴定出32种化学成分,主要为单萜和倍半萜类化合物,其中相对含量较高的有α-蒎烯(44.258%)、D-柠檬烯(23.426%)、β-蒎烯(8.674%)、石竹烯(3.462%)、β-月桂烯(3.018%)等.研究结果表明红松松塔挥发油中富含α-蒎烯、D-柠檬烯、石竹烯等多种具有药理活性的成分.因此,红松松塔是一种具有较好前景的天然药用资源.     

HEPT类化合物的QSAR研究

为定量结构／活性相关性研究提取了量子化学参数,拓扑指数Am,分子连接性指数^mxt及疏水性常数,同时应用正交变换和最佳变量子集算法（Leaps-and-Bonds)进行了变量压缩和选择,进而实施了多元回归分析,并由此结果进行了HEPT类化合物（1－[(2-hydroxyethoxy)methyl]-6-(phenylthio)-thymine derivatives)的结构／活性关系的理论解释,进行了人工神经网络法对于该类化合物的活性预测,其结构明显好于多元回归法。     

From the Micro- to the Macro-: Managing the Conservation of the Warship,Vasa

Sweden's famous warship, Vasa, sank on her maiden voyage in August 1628, and remained on the bottom of Stockholm harbour for 333 years. Raised in 1961, she became the first large-scale wooden object to be treated with polyethylene glycol (PEG). In the summer of 2000 a number of acidic salt precipitations were noticed on the surface of the ship and on wooden artefacts in the storerooms. An international research project has been established to look into the causes of this problem and suggest possible re-treatments. Meanwhile projects are underway to monitor movements in the ship, to build a better support system, and to replace the thousands of iron bolts holding the structure together, while a sophisticated new climate system has recently been installed in the museum.     

液滴荧光传感与计算机联用技术在微量分析中的应用

通过在LS55型荧光-磷光-发光分光光度计上加装液滴产生及调节附件,采用计算机采集与分析处理数据,成功地研制了双通道液滴光化学传感装置.利用葡聚糖凝胶对复合维生素B中不同组分的选择性吸附来达到分离与同时检测的目的,并将其用于复合维生素B药片的分析,取得了满意的结果.     

Using of the Agglomeration-in-liquid for the Technology of the Fine Materials

The content of the fine and ultrafine particles in the raw material results in difficulty of the separation, the loss of the valuable components and ecological contamination. Secondary using of the fine particles is impossible without their granulation. This problem has been solved by the agglomeration-in-liquid method.An agglomeration-in-liquid method is a process to produce agglomerates in a liquid phase from solid particles suspended in the liquid. The surface of solid particles and the binding liquid must be of identical polarity, but the continuous phase must be of the opposite polarity. The water solutions of the surfactant are the binding liquids or the organic liquids.     

On the scaling of the interface energy of the liquid clusters in the disordered nanoporous medium

Similarity of the extrusion curves of non-wetting liquid in a nanoporous medium with different initial fill volume fractions is observed experimentally. The similarity can be explained by the scaling of the interface energy and the self-similarity of the infinite percolation cluster of fluid-filled pores. Understanding the physical processes leading to the observed phenomena is a foundation for the development of high-performance devices for damping and energy storage on the basis of such heterogeneous systems.     

光亮剂对银电沉积行为的影响

用电势阶跃法和旋转圆盘电极法 (RDE)以及SEM和XRD测试手段 ,初步研究了光亮剂对氰化体系中银电沉积行为的影响 .研究表明 ,光亮剂的加入并未导致银电沉积成核机理的改变 ,但显著增强了镀液的微观平整效应 ,并且所得镀层的表观光滑程度明显改善 .XRD测试亦同时表明光亮剂的加入并未改变镀层的择优取向     

On the quality of the hardness kernel and the Fukui function to evaluate the global hardness

An approximated hardness kernel, which includes the second derivative with respect to the density of the kinetic energy, the electron-electron coulomb repulsion, and the exchange density functionals, has been tested for the calculation of the global hardness. The results obtained for a series of 40 cations and neutral systems and 16 anions represent in most cases an improvement of the results obtained using the HOMO-LUMO gap approach and indicate the viability of this approach to evaluate global hardness. In addition, the relevance of the Fukui function approximation and the role of the three components of the hardness kernel in the evaluation of the global hardness have been analyzed.     

Copper-containing dendromesogens: the influence of the metal on the mesomorphism

The synthesis and liquid crystalline behaviour of the first and second generations of a dendrimeric structure based on poly(propyleneimine)(DAB-dendr(NH₂)_x) are reported. 4-(4-n-Alkoxybenzoyloxy)salicylaldehydes are used as mesogenic moieties attached at the peripheral amino groups of the dendrimers giving rise to dendromesogens with four and eight mesogenic branches. From these dendromesogens, considered as organic ligands, were prepared six metal-containing dendrimers which incorporate two or four copper atoms in their structures. All the dendrimeric ligands and three of the metal-containing dendrimers exhibit liquid crystalline properties which were studied by optical microscopy, DSC, X-ray diffraction and EPR spectroscopy.     

Influence of the Position of the Connecting Spacer of the Chromophore on the Nonlinear Optical Response

A new chromophore, C1 , based on a similar DπA‐structure as in the FTC ‐chromophore but with a hydroxyalkyl spacer perpendicular to the direction of the dipole moment was synthesized. Both chromophores and the CLD ‐chromophore were used to prepare high T_g nonlinear optical vinyl polymers. The influence of the position of the spacer on the DπA‐system on the NLO response of the resulting polymers was investigated.