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1.
概述了气相色谱法以及衍生气相色谱法多年来在食品分析中发挥的作用,较详尽地介绍了近年来气相色谱-质谱联用法在食品营养成分-脂肪酸、糖类、维生素类分析方面的应用.  相似文献   

2.
通过列举甜蜜素、甘油、面粉增白剂、克球酚、苏丹红I、三聚氰胺等典型实例,介绍了近年来气相色谱法、气相色谱-质谱联用法在食品添加剂及毒物分析方面的应用.  相似文献   

3.
任志强  杨虹 《科技信息》2009,(30):I0332-I0333
卷烟包装纸中挥发性有机化合物的分析一般采用顶空—气相色谱法,该方法需分别用顶空—气相色谱/质谱联用法定性及顶空—气相色谱法定量。本方法使用顶空—气质联用法直接分析了卷烟包装纸中的15种挥发性有机化合物的含量,简化了分析步骤,且方法准确、快速、可靠。  相似文献   

4.
从苣荬菜的花中提取了挥发油。用气相色谱-质谱联用法分析其挥发油的化学成分。鉴定出31个化合物,并用气相色谱测定了挥发油中各成分的相对含量.  相似文献   

5.
从苣荬菜的花中提取了挥发油,用气相色谱-质谱联用法分析其挥发油的化学成分,鉴定出31个化合物,并用气相色谱测定了挥发油中各成分的相对含量.  相似文献   

6.
宁夏固原百里香挥发油化学成分的GC-MS研究   总被引:6,自引:0,他引:6  
用水蒸气蒸馏法提取宁夏固原百里香挥发油,利用气相色谱-质谱联用法(GC-MS)对其化学成分进行了分析鉴定,共鉴定出31种组分.用归-化法对各成分进行定量,含量最高的4种组分为香荆芥酚(28.54%),1-甲基-3-异丙基苯(22.77%),百里香酚(11.45%)和1-甲基-4-异丙基-1,4-环己二烯(9.78%),31种组分共占挥发油总量的98.33%.  相似文献   

7.
采用气相色谱法结合气相色谱-质谱联用技术(GC-MS)对铁基和钴基催化剂费-托合成反应水相产物中的含氧有机化合物进行了定性及定量分析,建立了费-托合成水相产物中含氧有机化合物的气相色谱外标定量分析方法.研究表明: 费-托合成反应的水相产物中主要含有醇、醛、酮、酸、酯等含氧有机化合物,其中醇类物质含量最高,酸、酮、醛、酯的含量较低,钴基催化剂的反应产物中基本不含有酸类物质,铁基催化剂费-托合成的水相产物中含氧有机化合物的种类和含量均高于钴基催化剂.  相似文献   

8.
百里香挥发性成分的研究   总被引:10,自引:0,他引:10  
采用水蒸气蒸馏法提取,同时采用毛细管气相色谱.质谱联用法对百里香的挥发性化学成分进行了分析研究,经毛细管色谱分离出81多个峰,并且确认了所含的68种化合物.用气相色谱面积归一法测定了各成分的相对百分含量,其主要化学成分为:百里酚(36.08%)、1.甲基-3-(1.甲基乙基)苯(12.11%)、7,11-二甲基.1,6,10-十二三烯(6.88%)、2-甲基-5-(1-甲基乙基)-苯酚(4.86%)、桉油醇(4.21%)、1.甲氧基-4-甲基-2-(1-甲基)苯(3.78%)等,为进一步开发利用提供了科学依据.  相似文献   

9.
国内色谱法研究人体内脂肪酸的综述   总被引:1,自引:0,他引:1  
文章对国内色谱法研究人体内脂肪酸的文献进行了综述,包括气相色谱法(GC)、气相色谱质谱联用法(GC/MS)、高效液相色谱法(HPLC)。同时对脂肪酸测定结果与人的营养和疾病之间的关系进行了一定的探讨。  相似文献   

10.
作者建立了检测银杏内酯B(原料药)中石油醚(60~90℃)残留的方法.以甲醇为萃取溶剂,采用超声提取法对样品进行前处理,采用气相色谱-质谱联用法进行检测.结果表明:该法在5 min内能较好地分离石油醚的所有组分,样品的加样回收率(n=6)为98.8%,RSD为2.55%,低检测限为1.61×10-5μg.该法具有灵敏、准确、快速等特点.  相似文献   

11.
The discovery of the prolific Ordovician Red River reservoirs in 1995 in southeastern Saskatchewan was the catalyst for extensive exploration activity which resulted in the discovery of more than 15 new Red River pools. The best yields of Red River production to date have been from dolomite reservoirs. Understanding the processes of dolomitization is, therefore, crucial for the prediction of the connectivity, spatial distribution and heterogeneity of dolomite reservoirs.The Red River reservoirs in the Midale area consist of 3~4 thin dolomitized zones, with a total thickness of about 20 m, which occur at the top of the Yeoman Formation. Two types of replacement dolomite were recognized in the Red River reservoir: dolomitized burrow infills and dolomitized host matrix. The spatial distribution of dolomite suggests that burrowing organisms played an important role in facilitating the fluid flow in the backfilled sediments. This resulted in penecontemporaneous dolomitization of burrow infills by normal seawater. The dolomite in the host matrix is interpreted as having occurred at shallow burial by evaporitic seawater during precipitation of Lake Almar anhydrite that immediately overlies the Yeoman Formation. However, the low δ18O values of dolomited burrow infills (-5.9‰~ -7.8‰, PDB) and matrix dolomites (-6.6‰~ -8.1‰, avg. -7.4‰ PDB) compared to the estimated values for the late Ordovician marine dolomite could be attributed to modification and alteration of dolomite at higher temperatures during deeper burial, which could also be responsible for its 87Sr/86Sr ratios (0.7084~0.7088) that are higher than suggested for the late Ordovician seawaters (0.7078~0.7080). The trace amounts of saddle dolomite cement in the Red River carbonates are probably related to "cannibalization" of earlier replacement dolomite during the chemical compaction.  相似文献   

12.
AcomputergeneratorforrandomlylayeredstructuresYUJia shun1,2,HEZhen hua2(1.TheInstituteofGeologicalandNuclearSciences,NewZealand;2.StateKeyLaboratoryofOilandGasReservoirGeologyandExploitation,ChengduUniversityofTechnology,China)Abstract:Analgorithmisintrod…  相似文献   

13.
本文叙述了对海南岛及其毗邻大陆边缘白垩纪到第四纪地层岩石进行古地磁研究的全部工作过程。通过分析岩石中剩余磁矢量的磁偏角及磁倾角的变化,提出海南岛白垩纪以来经历的构造演化模式如下:早期伴随顺时针旋转而向南迁移,后期伴随逆时针转动并向北运移。联系该地区及邻区的地质、地球物理资料,对海南岛上述的构造地体运动提出以下认识:北部湾内早期有一拉张作用,主要是该作用使湾内地壳显著伸长减薄,形成北部湾盆地。从而导致了海南岛的早期构造运动,而海南岛后期的构造运动则主要是受南海海底扩张的影响。海南地体运动规律的阐明对于了解北部湾油气盆地的形成演化有重要的理论和实际意义。  相似文献   

14.
Various applications relevant to the exciton dynamics,such as the organic solar cell,the large-area organic light-emitting diodes and the thermoelectricity,are operating under temperature gradient.The potential abnormal behavior of the exicton dynamics driven by the temperature difference may affect the efficiency and performance of the corresponding devices.In the above situations,the exciton dynamics under temperature difference is mixed with  相似文献   

15.
The elongation method,originally proposed by Imamura was further developed for many years in our group.As a method towards O(N)with high efficiency and high accuracy for any dimensional systems.This treatment designed for one-dimensional(ID)polymers is now available for three-dimensional(3D)systems,but geometry optimization is now possible only for 1D-systems.As an approach toward post-Hartree-Fock,it was also extended to  相似文献   

16.
17.
The explosive growth of the Internet and database applications has driven database to be more scalable and available, and able to support on-line scaling without interrupting service. To support more client's queries without downtime and degrading the response time, more nodes have to be scaled up while the database is running. This paper presents the overview of scalable and available database that satisfies the above characteristics. And we propose a novel on-line scaling method. Our method improves the existing on-line scaling method for fast response time and higher throughputs. Our proposed method reduces unnecessary network use, i.e. , we decrease the number of data copy by reusing the backup data. Also, our on-line scaling operation can be processed parallel by selecting adequate nodes as new node. Our performance study shows that our method results in significant reduction in data copy time.  相似文献   

18.
R-Tree is a good structure for spatial searching. But in this indexing structure,either the sequence of nodes in the same level or sequence of traveling these nodes when queries are made is random. Since the possibility that the object appears in different MBR which have the same parents node is different, if we make the subnode who has the most possibility be traveled first, the time cost will be decreased in most of the cases. In some case, the possibility of a point belong to a rectangle will shows direct proportion with the size of the rectangle. But this conclusion is based on an assumption that the objects are symmetrically distributing in the area and this assumption is not always coming into existence. Now we found a more direct parameter to scale the possibility and made a little change on the structure of R-tree, to increase the possibility of founding the satisfying answer in the front sub trees. We names this structure probability based arranged R-tree (PBAR-tree).  相似文献   

19.
The geographic information service is enabled by the advancements in general Web service technology and the focused efforts of the OGC in defining XML-based Web GIS service. Based on these models, this paper addresses the issue of services chaining,the process of combining or pipelining results from several interoperable GIS Web Services to create a customized solution. This paper presents a mediated chaining architecture in which a specific service takes responsibility for performing the process that describes a service chain. We designed the Spatial Information Process Language (SIPL) for dynamic modeling and describing the service chain, also a prototype of the Spatial Information Process Execution Engine (SIPEE) is implemented for executing processes written in SIPL. Discussion of measures to improve the functionality and performance of such system will be included.  相似文献   

20.
Advances in wireless technologies and positioning technologies and spread of wireless devices, an interest in LBS (Location Based Service) is arising. To provide location based service, tracking data should have been stored in moving object database management system (called MODBMS) with proper policies and managed efficiently. So the methods which acquire the location information at regular time intervals then, store and manage have been studied. In this paper, we suggest tracking data management techniques using topology that is corresponding to the moving path of moving object. In our techniques, we update the MODBMS when moving object arrived at a street intersection or a curved road which is represented as the node in topology and predict the location at past and future with attribute of topology and linear function. In this technique, location data that are corresponding to the node in topology are stored, thus reduce the number of update and amount of data. Also in case predicting the location,because topology are used as well as existing location information, accuracy for prediction is increased than applying linear function or spline function.  相似文献   

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