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1.
为建立高效液相色谱-蒸发光散射检测法(HPLC-ELSD)同步定量测定烟草中果糖、葡萄糖的新方法,将烟草样品处理后,用水提取,用Kromasil NH2柱分离,以乙腈-水(80∶20,V/V)为流动相,流速1.0 m L/min,柱温为室温,进样量20μL,ELSD漂移管温度95℃,空气作载气,流速1.5 L/min,使用蒸发光散射检测器进行了单糖检测.结果表明:果糖、葡萄糖的线性范围分别为0.273~2.73 mg/m L,0.294~2.94 mg/m L,在线性范围内糖含量与峰面积线性关系良好;样品中糖的加标回收率范围为98.5%~102.8%,测得烟草样品中果糖、葡萄糖含量分别为10.44%、7.40%故该方法具有快速、有效、质量可控等优点,为烟草中糖含量的测定提供了一种行之有效的分析方法.  相似文献   

2.
应用紫外光谱法结合主成分分析法,对掺入梨汁、甘蔗汁和葡萄糖、果糖及蔗糖溶液的掺假苹果汁进行了快速检测;同时,对苹果汁在室温储藏过程中营养物质的变化进行了研究.实验结果表明:紫外光谱法结合主成分分析法可以较好地检测出掺假的苹果汁,尤其是掺梨汁的苹果汁;苹果汁在室温储藏时,其可溶性固形物、维生素C、黄酮、总糖和还原糖的含量、pH值、抗氧化活性都呈降低的趋势,总酚含量则相对稳定.  相似文献   

3.
青龙衣多糖的提取及单糖组分和质量分数测定   总被引:4,自引:2,他引:4  
提取青龙衣多糖,经纯化后,分析其单糖组分并测定其总糖质量分数.水提醇沉法提取粗多糖,酸性条件下离心脱色,Sevage法除蛋白,H2O2脱结合色素,高效毛细管电泳(HPCE)测定单糖组成,苯酚-硫酸法测定质量分数.青龙衣粗多糖提取率为38.07%,精制多糖为76.08%;主要单糖组分为半乳糖(Gal)、葡萄糖(G lu)、阿拉伯糖(Ara)、鼠李糖(Rha)、果糖(Fru),其百分比分别为42.998%、23.30%、16.03%、10.123%、7.549%.高效毛细管电泳分离度高,可用于单糖组分定量、定性分析;苯酚-硫酸法实验操作简便,准确可靠,可用于青龙衣多糖质量分数的测定.  相似文献   

4.
采用亲水色谱-电雾式检测器-电喷雾-飞行时间质谱,测定西洋参不同部位(芦头、主根、参须)中多糖的单糖组成。采用超声辅助酸解法对西洋参多糖进行完全水解,应用Waters Xbridge Amide柱(4.6 mm×250 mm,5 μm),梯度洗脱(A为乙酸铵水溶液,B为乙腈),流速0.8 mL/min,柱温40 ℃,ESI-TOF/MS进行定性鉴别,CAD检测器(雾化器温度60 ℃,N2压力8.8 kPa)进行定量测定,结合主成分分析对西洋参不同部位进行区分。该方法在一定质量浓度范围内具有良好的线性(相关系数>0.999 1),检出限为0.03~0.13 μg/mL,平均回收率为94.17%~107.15%。应用该方法测定了西洋参不同部位多糖水解产物中7种单糖(葡萄糖、果糖、阿拉伯糖、鼠李糖、木糖、岩藻糖、甘露糖)和2种糖醛酸(半乳糖醛酸、葡萄糖醛酸),主根中葡萄糖含量较高,其平均值为(2.123±0.070)mg/g;芦头中鼠李糖、阿拉伯糖、果糖、甘露糖、葡萄糖醛酸、半乳糖醛酸含量较高,其平均值分别为(0.037±0.006)mg/g、(0.179±0.023)mg/g、(0.158±0.028)mg/g、(0.036±0.006)mg/g、(0.069±0.007)mg/g、(0.376±0.096)mg/g;参须中岩藻糖含量较高,其平均值为(0.120±0.005)mg/g。该方法简单,灵敏度、重复性好,为西洋参单糖组成和不同药用部位开发利用提供了方法和数据支持。  相似文献   

5.
云南普洱茶产地土壤理化性状分析   总被引:1,自引:0,他引:1  
选择云南省普洱茶产地普洱市、临沧市和西双版纳州为研究区,对不同的土壤类型和土壤各层的理化性质进行分析,并结合茶园的生长情况,研究了土壤理化性质的适宜性.结果表明:1)普洱茶主产区各种土壤类型中,赤红壤的N、P、K的质量分数(w)均偏低,对茶树生长的限制因素较多.黄壤的全P、全K含量丰富,适合茶树生长的有利条件较多.其他土壤类型中,K和P是茶树生长的主要限制因子;2)表、心、底土层的质地一般为粉砂质壤土,是pH范围为4~5的微酸性土壤,存在土壤表层酸化的趋势;3)土壤有机质层深厚,w(全N)达到1%~2%;w(速效P)较低,且从表、心、底土层逐渐减少.w(K)较高,w(全K)平均值在0.6%~1.0%,w(有效K)在土壤表层的积累较明显;微量元素中,Fe、Mn元素w较高;4)有效P、有效K及微量元素Fe和Mn对普洱茶茶叶的生长有重要的作用.  相似文献   

6.
目的:研究山楂多糖的总多糖含量及单糖组分构成.方法:用苯酚-硫酸法测定山楂多糖中的中性多糖含量,用间羟基联苯法测山楂多糖中糖醛酸含量,用红外光谱法初步探究山楂多糖官能团,用气相色谱法分析山楂多糖中单糖组分.结果:山楂多糖中中性多糖的含量为72.00%;糖醛酸的含量为14.98%;红外光谱分析表明山楂多糖可能为一种氨基多糖;气相色谱法分析得山楂多糖的单糖组成为木糖、核糖、阿拉伯糖、鼠李糖、果糖、葡萄糖、半乳糖,其质量分数分别为5.53%、13.85%、14.26%、9.29%、8.37%、19.91%、21.93%.结论:该方法比较便捷,重复性好,可用于山楂多糖中单糖的组成成分分析.  相似文献   

7.
采用强制通风静态好氧堆肥工艺,对餐厨垃圾和污泥进行联合堆肥化处理,探究二者不同配比对堆肥氮素转化及氮素损失的影响.以w(C)/w(N)=15~40的5组餐厨垃圾和污泥作为堆肥基质,以木屑作为调理剂进行堆肥试验.结果表明:所有堆体温度均先升高后降低,最高温度为78℃,w(C)/w(N)越高,堆体的最高温度越低,且达到最高温度的时间越长,pH先降低后升高至8.5趋于平缓,总有机碳质量分数不断降低.各堆体全氮和有机氮质量分数先升高后显著降低,铵态氮质量分数先增加后略有减少,硝态氮质量分数很低且变化不大.二者联合堆肥中氮损失27.8%~48.4%,且与投加的污泥含量呈正相关关系,氨挥发占氮损失的52.6%~80.4%,氨挥发是氮损失的主要途径,且随着堆体w(C)/w(N)的增加呈减少趋势.  相似文献   

8.
为研究大麻药多糖成分中单糖的组成,用3 mol·L-1三氟乙酸将大麻药多糖水解成单糖,再与盐酸羟胺进行衍生化反应,用气相色谱法分析了其单糖组成,结果表明:鼠李糖、阿拉伯糖、果糖、葡萄糖、阿洛糖和半乳糖为大麻药多糖成分中的单糖组成,其质量分数依次为15.86%,20.37%,6.62%,14.24%,8.38%和14.15%.此方法简便、快速,重现性好,可用于大麻药多糖成分中单糖的组成分析.  相似文献   

9.
巴戟天多糖的分级纯化及结构分析   总被引:14,自引:0,他引:14  
对巴戟天多糖的柱层析分级纯化和一级结构进行了研究.采取热水浸提、乙醇沉淀的工艺获得巴戟天粗多糖MOHP,经离子交换和凝胶柱层析得到了MOHP-I,MOHP-Ⅱ,MOHP-Ⅲ和MOHP-Ⅳ4 个组分,通过红外光谱、液相和气相色谱等分析手段对分级后的MOHP-Ⅰ和MOHP-Ⅲ进行了初步的结构分析.结果表明:MOHP—Ⅰ的单糖组成为葡萄糖和果糖,分子质量约为2ku,呋喃糖环结构;MOHP-Ⅲ是一种均一的糖蛋白物质,其组成单糖为阿拉伯糖、木糖、葡萄糖、果糖以及半乳糖,分子质量约为35ku;高效凝胶渗透色谱显示两组分均达到了较高的纯度.  相似文献   

10.
在食品真实属性表征生物识别新技术研究方面,采用分子生物学技术,针对燕窝、王浆、海参等常见高附加值食品建立真伪鉴别新方法,为政府监管,企业质控提供技术保障,包括:采用免疫检测、酶活检测、毛细管电泳等技术,建立蜂王浆品质识别方法,收集不同产地和蜜源的王浆样品,初步建立了王浆属性表征数据库,进一步为王浆真伪鉴别和品质评价的应用奠定了基础;针对银耳、红藻、猪皮、蛋清等燕窝掺假物,建立燕窝真伪鉴别实时荧光PCR检测方法研究,开发燕窝真伪鉴别液相芯片检测方法,提高检测通量。采用双向电泳技术开展不同产地和级别燕窝样品的蛋白质组比较,为燕窝产品品质识别积累了基础数据。在蜂蜜蜜源品种溯源方面,建立8种蜂蜜蜜源植物的实时荧光PCR检测方法,可以灵敏检测不同蜜源蜂蜜混杂的产品。在鲑鱼和海参等海产品真伪检测方面,建立鲑鱼和海参真伪鉴别实时荧光PCR方法。在食品感官品质仿生识别技术研究与设备开发方面,开发了食品感官品质多通道识别信息融合技术与质量决策系统,采用传感器电子鼻、可视化电子鼻、电子舌等现代智能感官分析技术及气相色谱-质谱技术,针对普洱茶、绿茶、蜂蜜等食品建立品质识别新方法,为规范市场提供科学手段,包括:初步建立多种信息融合模式下的产品质量检测模型,开展了智能化电子舌传感器清洗、漂移校正、系统集成、标准操作应用方法学等产业化关键技术的研究,开发了利用4种天然植物色素作为气体敏感材料的可视化电子鼻技术,进行猪肉新鲜度检测应用研究,针对普洱茶品质和产地、绿茶产地、食用油品种等建立电子鼻品质识别方法。在食品质量属性分子识别技术及装备研究方面,重点针对组胺分子印迹技术、癸烯酸仿生免疫技术、蜂蜜红外光谱检测技术、杂胺免疫检测技术开展研究,包括:在前期组胺分子印迹聚合物合成的基础上,进一步优化构建了组胺分子印迹压电石英微天平传感器,并将其应用于实际样品的测定。建立了10-羟基-癸烯酸仿生免疫层析和高效液相色谱仪联用的检测方法来检测蜂王浆及其制品中蜂王酸的含量。采用近红外光谱技术结合化学计量学方法对掺入不同质量分数果葡糖浆的掺假蜂蜜进行定性和定量分析。在杂环胺半抗原合成、抗体制备的基础上优化建立了竞争ELISA方法,并优化建立了样品基质消除方法,对实际样品进行检测,并与仪器分析方法进行了比对。  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.
There are numerous geometric objects stored in the spatial databases. An importance function in a spatial database is that users can browse the geometric objects as a map efficiently. Thus the spatial database should display the geometric objects users concern about swiftly onto the display window. This process includes two operations:retrieve data from database and then draw them onto screen. Accordingly, to improve the efficiency, we should try to reduce time of both retrieving object and displaying them. The former can be achieved with the aid of spatial index such as R-tree, the latter require to simplify the objects. Simplification means that objects are shown with sufficient but not with unnecessary detail which depend on the scale of browse. So the major problem is how to retrieve data at different detail level efficiently. This paper introduces the implementation of a multi-scale index in the spatial database SISP (Spatial Information Shared Platform) which is generalized from R-tree. The difference between the generalization and the R-tree lies on two facets: One is that every node and geometric object in the generalization is assigned with a importance value which denote the importance of them, and every vertex in the objects are assigned with a importance value,too. The importance value can be use to decide which data should be retrieve from disk in a query. The other difference is that geometric objects in the generalization are divided into one or more sub-blocks, and vertexes are total ordered by their importance value. With the help of the generalized R-tree, one can easily retrieve data at different detail levels.Some experiments are performed on real-life data to evaluate the performance of solutions that separately use normal spatial index and multi-scale spatial index. The results show that the solution using multi-scale index in SISP is satisfying.  相似文献   

13.
AcomputergeneratorforrandomlylayeredstructuresYUJia shun1,2,HEZhen hua2(1.TheInstituteofGeologicalandNuclearSciences,NewZealand;2.StateKeyLaboratoryofOilandGasReservoirGeologyandExploitation,ChengduUniversityofTechnology,China)Abstract:Analgorithmisintrod…  相似文献   

14.
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   

15.
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   

16.
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   

17.
18.
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   

19.
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   

20.
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   

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