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1.
罗丹明B荧光光谱机理的研究   总被引:5,自引:0,他引:5  
考察了罗丹明B浓度、溶剂的极性、pH值大小、表面活性剂的增敏等因素对罗丹明B的荧光光谱影响,探讨了以上各因素影响罗丹明B的荧光光谱的机理.结果表明,随着罗丹明B浓度的增加,荧光光谱波长红移,强度先增后减;溶剂极性增加,波长红移,荧光强度则由于溶剂特殊效应的影响而减小;pH=1.0~3.0时,荧光强度随pH的增加而增大,pH>3.0时,荧光强度几乎无变化;阳离子表面活性剂对体系的荧光强度具有增敏作用,阴离子表面活性剂则相反.  相似文献   

2.
报道了一种基于苯并噻二唑衍生物的荧光传感器用于检测金属铜离子和氟离子。通过紫外可见光谱和荧光光谱研究此传感器检测离子的能力。研究表明,在所测试的阴离子中,只有氟离子可以引起此荧光探针的吸收峰蓝移(从390 nm到383 nm),并伴随着一定强度的减弱。同样氟离子可以引起此荧光探针的荧光强度降低并且蓝移(从496 nm到488 nm)。在所测试的阳离子中,铜离子可引起荧光探针的吸收峰红移,荧光强度淬灭90%。此外,当加入铜离子和氟离子的先后顺序不同时,引起的荧光光谱变化也不同。  相似文献   

3.
几种芴基衍生物荧光性质的初步研究   总被引:1,自引:0,他引:1  
以芴为原料合成了芴酮,芴醇,2,7-二溴基芴,2,7-二溴基芴酮,2,7-二溴基芴醇,二茂铁甲酸芴酯等芴基衍生物.测定了所合成芴基衍生物的荧光光谱,并讨论了结构对荧光光谱的影响.结果表明,共轭结构对荧光光谱的峰形影响很大;溴代略微影响光谱峰形,同时使特征峰轻微红移,强度略有下降,而不同发射波长峰的强度则发生无规律性变化,表明其他基团(如羟基)与溴代基团对化合物荧光光谱产生协同效应.  相似文献   

4.
以纯猪心肌高铁肌红蛋白(p Met Mb)为对象,建立荧光光谱条件并经同步荧光指认其主要功能域.研究表明,以600 nm/min扫描速度和中等响应时间为基本条件,p Met Mb的适宜荧光光谱条件分别是20 mmol/L p Met Mb、10 nm狭缝宽度和270 nm或430 nm为激发光波长.经同步荧光光谱解析,酪氨酸(Tyr-)、色氨酸(Trp-)和铁卟啉环(heme-Fe3+)荧光特征峰分别在312、355和630 nm处.270 nm是Trp-和Tyr-适宜激发光波长,而430 nm是heme-Fe3+适宜激发光波长.与马肌红蛋白(h Mb)比较,其Trp-和heme-Fe3+荧光光谱特征峰出现红移.430 nm可激发630 nm处heme-Fe3+,发生电子迁移和能量跃迁.随着Trp-和heme-Fe3+特征峰的红移,推测p Met Mb中heme-Fe由五配位高自旋(Fe2+)转变为六配位低自旋(Fe3+).  相似文献   

5.
通过在硼原子上引入大体积的芳香取代基合成稳定的含芘二米基硼化合物(Ⅰ)。经紫外可见吸收光谱和荧光光谱分析,研究其光物理性质及对F-的识别性质。结果表明:化合物具有较强的蓝色荧光发射,在四氢呋喃(THF)中荧光峰位为428 nm;由弱极性溶剂正己烷(荧光峰位在413 nm处)到强极性溶剂乙腈(荧光峰位在435 nm处),化合物荧光光谱峰值红移22 nm,荧光量子产率由0.98降为0.68;将四丁基氟化铵逐渐滴加入化合物Ⅰ的THF溶液中,其吸收光谱和荧光光谱均伴有旧峰消失和新峰出现的现象:吸收光谱的旧峰在383和399 nm处,新峰出现在324、338和353 nm处;荧光光谱的旧峰在429 nm处,新峰出现在385和403 nm处;继续滴加四丁基氰化铵,其吸收光谱和荧光光谱均无明显变化。  相似文献   

6.
使用无水ALCL3作为催化剂,通过本体聚合制备出具有良好荧光性能的聚苯乙炔,并用FT-IR。UV-Vis,PL对聚合物结构、性能进行了表征,研究了催化剂用量对聚合物分子量及荧光光谱的影响.结果发现,减少催化剂用量可使分子量增加,主链共轭体系增大,在紫外光谱和荧光光谱上表现出红移现象.另外,当选用不同波长(300、350、400nm)的光激发时,其荧光发射峰依次红移,说明所得聚苯乙炔可能含有多种异构链结构,存在不同的发光点.  相似文献   

7.
十二烷基硫酸钠对猕猴桃蛋白酶的变性作用   总被引:2,自引:3,他引:2  
应用光谱法观测酶的结构变化,紫外差光谱显示在233nm有一较明显的差吸收负峰,在286nm、300nm左右有不大的负峰和在265nm的正峰;荧光谱显示327nm的相对荧光强度随SDS浓度的增高而递减;发射峰位置红移,酶受SDS>4.1mmol/1作用1h,可引起310nm新荧光发射肩。动力学资料表明,SDS对酶的变性过程为一级反应;酶的失活分快慢相,呈现二个一级反应,同时测定在SDS作用下actinidin的变性与失活速度,表明酶的失活速度大于变性速度,似可认为低浓度SDS能使结构域相错开,从而敏感地改变活性部位的微区结构,导致酶快速失活,提高SDS浓度则使酶的结构域发生构象变化,引起光谱法所显示的特征。  相似文献   

8.
用荧光光谱和UV-Vis吸收光谱技术研究了肌红蛋白(Mb)和Cu^2 的相互作用,结果表明在水溶液中Cu^2 的加入使Mb中血红素在597nm处的荧光峰强度降低,也使Mb在407nm处的Soret带的吸收峰强度减弱,清楚地表明Cu^2 与Mb发生了相互作用。  相似文献   

9.
借助278nm和295nm激发的内源荧光光谱分析,考察不同pH值缓冲液中23kD、17kD蛋白构象变化.结果表明:295nm波长光激发时,23kD蛋白具有326nm荧光发射峰和360nm副峰;17kD蛋白具有328nm荧光发射峰和355nm副峰;278nm波长光激发时,23kD和17kD蛋白的最大荧光发射峰均在306nm处.与中性条件下相比,酸性(pH3.0~4.0)或碱性(pH8.0~9.0)缓冲液中,23kD蛋白和17kD蛋白的内源荧光光谱都发生显著变化:最大荧光峰位置和强度均不相同,340nm-360nm荧光发射副峰的强度增加.反映溶液中两种蛋白的构象易发生改变,离子键和氢键是维系23kD、17kD蛋白构象的重要因素之一。  相似文献   

10.
以溴代肽脂质BrC5Gly2C16与5,10,15-三苯基-20-对羟基苯基卟啉(HPTPP)为原料,合成一种可用作新型分子器件的卟啉-脂质体化合物P-GlyL。 采用元素分析、紫外可见光谱、红外光谱以及核磁共振等进行表征。 并对该化合物在不同浓度的金属离子Zn2+溶液中的紫外可见光谱和荧光光谱进行了研究。 结果表明,当加入Zn2+之后,形成的金属卟啉化合物荧光强度在650.0nm处下降,而在437.0nm和595.8nm处产生新的荧光发射峰,且荧光强度随着Zn2+浓度增加而增强,而同时349.0nm和698.5nm处的发射峰发生了0.5nm的红移且荧光强度增强。  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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