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1.
合成一类以萘酰亚胺为荧光团的反应型氟离子荧光探针,并利用叔丁基二甲基氯硅烷作为识别基团来实现对氟离子的检测.首先对分子结构进行表征,然后通过荧光分光光度计对荧光性能进行研究,检测限能够达到6.167×10~(-8)mol/L,实验结果表明该分子是一类红移型荧光探针,并对氟离子的检测效果很好.  相似文献   

2.
该文以大豆渣为原料制备荧光碳量子点,并将其用于食品添加剂柠檬黄的检测.制备荧光碳量子点的最佳生产工艺条件为:豆渣在200 ℃下碳化24 h,豆渣和水的固液比为1:2.根据淬灭反应效应实现豆渣碳量子点对食品添加剂柠檬黄的检测.检测结果显示:随着柠檬黄溶液浓度的增大,碳量子点溶液的荧光强度逐渐减弱,且呈良好的线性关系.实验结果证明所合成的荧光碳量子点可以应用于食品添加剂柠檬黄的检测,检测限为0.2 μmol,线性范围为0~16 μmol?L-1.  相似文献   

3.
以金片作为固体基质,通过自组装方式把荧光物质1-萘胺乙酸(NAA)间接组装在金表面,制备具有荧光特性的NAA/Cys/Au自组装膜.利用在酸性介质中,Mn2 可使NAA/Cys/Au自组装膜表面荧光产生猝灭,且荧光猝灭程度和Mn2 浓度在5.0×10-6~3.0×10-5 mol·L-1范围内呈现良好的线性关系,从而建立利用固体表面荧光检测Mn2 的新方法,其检测下限为9.64×10-7 mol·L-1.荧光被Mn2 猝灭后的自组装膜,可在NaOH溶液中实现膜表面荧光的再生.  相似文献   

4.
利用新型荧光试剂1,3,5,7-四甲基-8-苯基-(4'-O-(N-琥珀酰亚胺乙酸酯))-二氟化硼-二吡咯甲烷(TMPAB-OSu)为柱前衍生化试剂,在氰基色谱柱上通过梯度洗脱对三种儿茶酚胺神经递质进行了分离和检测.以乙腈-水为溶剂,pH7.5的硼酸-硼砂缓冲溶液中在30℃条件下衍生反应5 min后获得稳定的荧光衍生产物.激发波长和发射波长分别为497 nm和509 nm,实现了儿茶酚胺柱前衍生检测,方法的重现性好、灵敏度高.儿茶酚胺的线性相关系数大于0.9970,检出限为5 nmol/L.  相似文献   

5.
设计开发了一种在碱性条件下由溶菌酶包覆合成并稳定的荧光金纳米簇,并利用它实现对碱性蛋白酶的快速灵敏检测.其检测原理是碱性蛋白酶将包覆和稳定金纳米簇的溶菌酶进行水解,造成金纳米簇的荧光下降.通过关联荧光下降程度与碱性蛋白酶浓度的关系,可实现对碱性蛋白酶的定量检测.考察了金纳米簇与碱性蛋白酶溶液体积比、反应温度和反应时间对检测灵敏性的影响规律.结果表明:在金纳米簇与碱性蛋白酶溶液体积比为1∶9、反应温度为40,℃、反应时间为3,h的条件下,检测效果最好;该检测方法的线性范围可达2~2,000,μg/m L(即酶活检测范围为4×10-5~0.04 unit/m L),检测限为0.1μg/m L(即酶活检测限为2×10-6 unit/m L),且检测的专一性较好,有望应用于实际检测.  相似文献   

6.
流动注射化学发光测定马来酸氯苯那敏   总被引:1,自引:0,他引:1  
高锰酸钾在酸性条件下可氧化马来酸氯苯那敏,该反应产生的能量转移到罗丹明6G而产生化学发光,在体系中加入CTMAB可以进一步增强该体系的化学发光强度,据此建立了流动注射化学发光测定马来酸氯苯那敏的新方法。该方法线性范围为4.0×10-7g/mL~8.0×10-5g/mL,方法的检出限为3.2×10-8g/mL,对1.0×10-5g/mL的马来酸氯苯那敏进行了11次平行测定,相对标准偏差为2.8%;方法用于药剂中马来酸氯苯那敏含量的测定,结果与药典标准法测得值基本一致。  相似文献   

7.
应用差示扫描量热法、红外光谱法、核磁共振波谱法和高效液相色谱法对β-谷甾醇与马来酸酐的酯化产物进行了表征和分析.实验结果表明:β-谷甾醇与马来酸酐发生酯化反应,产物为β-谷甾醇马来酸单酯;用Hypers il ODS反相柱,以甲醇为流动相,在检测波长为210 nm、柱温为25℃、流速为0.7 mL.m i-n 1的实验条件下进行液相色谱分析,β-谷甾醇及其马来酸单酯能够达到基线分离,采用外标法对β-谷甾醇及其马来酸单酯进行了定量分析,相对误差在±5%之间.外标法测得β-谷甾醇及其马来酸单酯的回收率接近100%.  相似文献   

8.
单扫描示波极谱法测定酒石酸中的马来酸   总被引:2,自引:0,他引:2  
建立了极谱测定酒石酸中马来酸含量的方法。在4.8×10-2mol/LH3PO4-KH2PO4(pH1.12)缓冲溶液中,马来酸极谱还原波的峰电位Ep为-0.77V(vs.SCE),其二阶导数峰峰电流i″p与马来酸浓度在3.0×10-7~4.0×10-4mol/L范围内呈线性关系(r=0.9974,n=8)。10次测量1.6×10-5mol/L马来酸还原波二阶导数峰峰电流,相对标准偏差RSD为2.1%。1000(w/w)倍酒石酸不干扰测定。通过对四种合成样品中马来酸的测定和回收率试验考察该方法,结果令人满意。  相似文献   

9.
制备一种基于共振能量转移机理的方酰胺衍生物荧光探针SA,用于检测芳香族硝基炸药.在二甲基亚砜/水缓冲溶液中,基于芳香族硝基炸药与探针相互作用后形成配合物可以有效淬灭探针SA的荧光,并伴随着紫外吸收的显著增强和溶液颜色的明显变化,在紫外-可见吸收光谱和荧光发射光谱双通道下实现对TNT的检测分析,在荧光发射光谱通道下实现对NT、DNT、TNP的检测分析.  相似文献   

10.
采用化学物质衍生结合同步荧光法,建立一种检测注射液中γ-氨基丁酸含量的方法.对γ-氨基丁酸的衍生产物进行同步荧光扫描,考察了影响体系荧光强度的因素.最佳实验条件为:8.0×10-3 mol/L硼砂缓冲液(pH=9.6),1.0×10-5 mol/L邻苯二甲醛-2.86×10-5 mol/Lβ-巯基乙醇组合试剂为衍生试剂,衍生时间60min,激发光、发射光通带宽度为5.0nm,λem=455.0nm,Δλ=120.0nm,检测液温度小于25℃.结果表明:在上述条件下获得的同步荧光光谱峰形最好,荧光强度最大.γ-氨基丁酸的线性范围为2.50~50.00μg/L,相关系数为0.999 0,检测限为0.79μg/L.本方法灵敏度高,操作简便,成本低,可用于注射液中γ-氨基丁酸含量的检测.  相似文献   

11.
Language markedness is a common phenomenon in languages, and is reflected from hearing, vision and sense, i.e. the variation in the three aspects such as phonology, morphology and semantics. This paper focuses on the interpretation of markedness in language use following the three perspectives, i.e. pragmatic interpretation, psychological interpretation and cognitive interpretation, with an aim to define the function of markedness.  相似文献   

12.
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   

13.
何延凌 《科技信息》2008,(4):258-258
Language is a means of verbal communication. People use language to communicate with each other. In the society, no two speakers are exactly alike in the way of speaking. Some differences are due to age, gender, statue and personality. Above all, gender is one of the obvious reasons. The writer of this paper tries to describe the features of women's language from these perspectives: pronunciation, intonation, diction, subjects, grammar and discourse. From the discussion of the features of women's language, more attention should be paid to language use in social context. What's more, the linguistic phenomena in a speaking community can be understood more thoroughly.  相似文献   

14.
AcomputergeneratorforrandomlylayeredstructuresYUJia shun1,2,HEZhen hua2(1.TheInstituteofGeologicalandNuclearSciences,NewZealand;2.StateKeyLaboratoryofOilandGasReservoirGeologyandExploitation,ChengduUniversityofTechnology,China)Abstract:Analgorithmisintrod…  相似文献   

15.
理论推导与室内实验相结合,建立了低渗透非均质砂岩油藏启动压力梯度确定方法。首先借助油藏流场与电场相似的原理,推导了非均质砂岩油藏启动压力梯度计算公式。其次基于稳定流实验方法,建立了非均质砂岩油藏启动压力梯度测试方法。结果表明:低渗透非均质砂岩油藏的启动压力梯度确定遵循两个等效原则。平面非均质油藏的启动压力梯度等于各级渗透率段的启动压力梯度关于长度的加权平均;纵向非均质油藏的启动压力梯度等于各渗透率层的启动压力梯度关于渗透率与渗流面积乘积的加权平均。研究成果可用于有效指导低渗透非均质砂岩油藏的合理井距确定,促进该类油藏的高效开发。  相似文献   

16.
As an American modern novelist who were famous in the literary world, Hemingway was not a person who always followed the trend but a sharp observer. At the same time, he was a tragedy maestro, he paid great attention on existence, fate and end-result. The dramatis personae's tragedy of his works was an extreme limit by all means tragedy on the meaning of fearless challenge that failed. The beauty of tragedy was not produced on the destruction of life, but now this kind of value was in the impact activity. They performed for the reader about the tragedy on challenging for the limit and the death.  相似文献   

17.
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   

18.
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   

19.
20.
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   

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