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1.
在8.0×10-3 mol/L HCl-2.0×10-3 mol/L KI介质中,吖啶橙(AO)在515 nm处有1个同步荧光峰.当有NO-2存在时,NO-2与过量的I-反应生成I-3,I-3与AO形成缔合微粒,在320,560 nm处产生2个共振散射(RS)峰,在470 nm处产生1个同步散射峰.NO-2浓度在0.068~7.36 mg/L范围内与320 nm波长处的共振散射光强度成线性关系.据此建立了一个测定水中NO-2的共振散射光谱分析法.光谱研究结果表明,(AO-I3)n缔合微粒和界面的形成是导致体系RS增强的根本原因.  相似文献   

2.
基于罗丹明S缔合微粒荧光猝灭效应测定ClO-   总被引:1,自引:1,他引:0  
在稀盐酸介质中,ClO^-与过量的I^-反应生成I3^-,I3^-与罗丹明S(RhS)、罗丹明B(RhB)及丁基罗丹明B(b-RhB)形成缔合微粒而导致各体系的荧光分别在550,580,580nm处发生猝灭.ClO^-浓度分别在0.020~0.35,0.020~0.51,0.020~0.35mg/L范围内与各体系的荧光猝灭强度成线性关系.各体系的检测限分别为0.016,0.028,0.029mg/L.据此建立了测定次氯酸根的荧光猝灭分析法.其中ClO^- -KI-RhS体系的灵敏度高而且稳定性较好,用于漂渍液和漂白粉中ClO^-的测定,并与碘量法对照,结果满意.  相似文献   

3.
在8.0×10-3mol/LHCl-2.0×10-3mol/LKI介质中,吖啶橙(AO)在515nm处有1个同步荧光峰.当有NO-2存在时,NO-2与过量的I-反应生成I-3,I-3与AO形成缔合微粒,在320,560nm处产生2个共振散射(RS)峰,在470nm处产生1个同步散射峰.NO-2浓度在0.068~7.36mg/L范围内与320nm波长处的共振散射光强度成线性关系.据此建立了一个测定水中NO-2的共振散射光谱分析法.光谱研究结果表明,(AO-I3)n缔合微粒和界面的形成是导致体系RS增强的根本原因.  相似文献   

4.
IO3--I3--吖啶红体系的共振散射光谱研究及应用   总被引:3,自引:3,他引:0  
在过量的I-存在的稀盐酸介质中,当有IO3-存在时,IO3-与过量的I-反应生成I3-,I3-与吖啶红、吖啶橙染料均可形成离子缔合微粒。吖啶红、吖啶橙分别在540、480 nm有较强吸收峰,在550、520 nm有较强荧光峰,吖啶红体系在605 nm处产生1个较强的共振散射(RS)峰,IO3-浓度在1.0×10-7~4.0×10-6mol/L与605nm波长处的共振散射光强度成线性关系。吖啶橙体系在560 nm处产生1个较强的共振散射(RS)峰,碘酸根浓度在2.0×10-7~1.2×10-5mol/L与560 nm波长处的共振散射光强度成线性关系。据此建立测定食盐中碘酸根的一种共振散射光谱法。采用此体系测定食盐中碘酸根,结果满意。  相似文献   

5.
Se(Ⅳ)与藻蓝蛋白相互作用的谱学研究   总被引:1,自引:0,他引:1  
用吸收、荧光、红外等谱学方法研究了藻蓝蛋白(PC)与Se(Ⅳ)的相互作用.结果表明,SeO3^2-加入后,藻蓝蛋白在620nm处的特征光吸收减弱,并随Se(Ⅳ)浓度和时间的增加而降低,而278和347nm处的光吸收增强;荧光发射和荧光激发也逐渐减弱,而599和629nm处的2个激发峰的相对强度与对照相反.PC在475和662nm处分别出现共振散射峰.Se(Ⅳ)与PC的作用后,在595nm处出现强的共振散射峰,被指认为液相纳米硒粒子与PC生成的缀合物的共振散射峰.红外光谱图中,PC的酰胺Ⅰ带为1653.2cm^-1,为α螺旋,而PC—Se(0)生物缀合物的酰胺Ⅰ带为1647.0cm^-1,属无规则卷曲。  相似文献   

6.
淀粉的共振散射光谱研究   总被引:6,自引:3,他引:3  
淀粉溶液在290,470和680nm处共产生3个共振散射峰.它是一种非线性光学介质,当激发波长为290nm时,淀粉超分子分别于290,580和870nm产生一个共振散射峰、一个1/2分频散射峰和一个1/3分频散射峰;当激发波长为680nm时,在680nm产生一个共振散射峰,而在340nm产生一个较该共振散射峰更强的2倍频散射峰,在227,450和907nm分别产生3倍频散射峰、3/2倍频散射峰和3/4分频散射峰.分频散射和倍频散射与共振散射有相似的散射行为.  相似文献   

7.
在pH8.0的Tris-HCl缓冲溶液及32mg/L PEG20000的存在下,碱性磷酸酯酶(ALP)催化底物5-溴-4-氯-3-吲哚基磷酸盐(BCIP)水解生成不溶性的蓝色BCIP二聚体微粒,该微粒在710nm波长处产生一个共振散射峰。在选定条件下,随着ALP活性增大,710nm波长处的共振散射峰强度线性增大,碱性磷酸酯酶浓度在0.078~1.25U/L与共振散射强度增大值ΔI呈良好线性关系,其回归方程为:ΔI=512.6C+17.8,检出限为9.6×10-3U/L。该法用于合成样品中碱性磷酸酯酶的测定,结果满意。  相似文献   

8.
近中性的BR (Britton-Robinson,H3PO4-HAc-H3BO3)缓冲溶液中,肝素钠与劳氏紫形成离子缔合物,在564 nm处生成新的瑞利共振散射(RRS)峰,随着肝素钠浓度的增加RRS峰显著增强,据此建立了劳氏紫瑞利共振散射荧光测定肝素钠的新方法.该方法在0.025~0.500 mg/L内RRS强度与肝素钠浓度呈良好的线性关系,线性回归方程为ΔI=0.125+16.88p(mg/L).用于肝素钠注射液含量测定,平行6次测定,相对标准偏差为1.67%~3.01%,方法回收率为104.0%~106.4%,结果满意.  相似文献   

9.
研究了汞(Ⅱ)-碘化物-结晶紫体系的共振瑞利散射(RRS)光谱.实验结果表明,在0.02mol/L的H2SO4溶液中,[HgI4]^2-与结晶紫在水相中由于静电引力和疏水作用力形成蓝色的离子缔合物时,产生相应的散射光谱,其最大RRS波长分别位于345nm和510nm.在0~0.4μg/mL范围内汞(Ⅱ)浓度与散射强度(△I)成正比.该法灵敏度高,选择性较好,操作简便,可直接用于水体中痕量汞(Ⅱ)的测定.  相似文献   

10.
用吸收、荧光、红外等谱学方法研究了藻蓝蛋白(PC)与Se(IV)的相互作用.结果表明,SeO2-3加入后,藻蓝蛋白在620nm处的特征光吸收减弱,并随Se(IV)浓度和时间的增加而降低,而278和347nm处的光吸收增强;荧光发射和荧光激发也逐渐减弱,而599和629nm处的2个激发峰的相对强度与对照相反.PC在475和662nm处分别出现共振散射峰.Se(IV)与PC的作用后,在595nm处出现强的共振散射峰,被指认为液相纳米硒粒子与PC生成的缀合物的共振散射峰.红外光谱图中,PC的酰胺I带为1653 2cm-1,为α螺旋,而PC-Se(0)生物缀合物的酰胺I带为1647 0cm-1,属无规则卷曲.  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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