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1.
该文根据薄膜理论基础,分析了受抑全内反射(FTIR)的理论机制,导出相应的光线透射率及反射率公式,从透射率、反射率随棱镜相对间隙d/λ、入射角θ0及折射率n的变化曲线可以看出,当间隙从0增加到一个波长量级时,透射率T从100%下降到0;在间隙一定的情况下,增大入射角或选用大折射率的材料,都会使透射率减小。并且建立了一套实验装置以对其特性进行具体分析。  相似文献   

2.
基于TGA—FTIR联用技术的PVC热解研究   总被引:4,自引:0,他引:4  
用TGA-FTIR联用的方式进行了PVC在空气条件下的热解实验,分别用DDTG曲线与FTIR的红外三维图、Gram-Schmidt(GGS)曲线等描述了PVC两个阶段的热解行为,对比了DDTG曲线与GGS曲线中峰的位置以及峰的起始时间、终止时间、峰宽等参数,结果表明,TGA与FTIR联用时,FTIR的检测无明显的滞后,及返混等情况发生。  相似文献   

3.
本文利用GC、GC/FTIR技术对一种新的稀料的组成进行了分析和鉴定,并得出定性和定量结果。  相似文献   

4.
采用快速Fourier变换红外光谱议(FTIR)对不同煤种及其灰渣的光学吸收指数k进行了测量,进而利用这些数据以及Mie光学理论计算得到了火焰辐射传热计算中所必须的重要参量──颗粒的散射和吸收有效因子以及相位函数。  相似文献   

5.
李卓 《开封大学学报》1999,13(2):21-23,31
本文以实验现象为依据,将Feinberg理论从锐角扩展到钝角,从而设计出钝角异型钛酸钡晶体自泵浦相位共轭镜(SPPCM),用该自泵浦相位共轭镜获得了大于40%的相位共轭反射率。文中还给出了部分实验曲线和其它实验结果。  相似文献   

6.
采用快速Fourier变换红外光谱议(FTIR)对不同煤种及其灰渣的光学吸收指数K进行了测量,进而利用这些数据以及Mie光学理论计算得到了火焰辐射传热计算中所必须的重要参量--颗粒的散射和吸收有效因子以及相位函数。  相似文献   

7.
该文根据薄膜理论基础,分析了受抑全内反射的理论机制,导出相应的光线透射率及反射率公式,从透射率,反射率随棱镜相对间隙d/λ、入角角θ0及折射率n的变化曲线可以看出,当间隙从0增加到一个波长量级时,透射率T从100%下降到0;  相似文献   

8.
紫外光与可见光对动物内脏器官通透性的研究   总被引:1,自引:0,他引:1  
利用带有积分球装置的双光路扫描分光光度计,系统地测量了内脏器官对波长为200~900nm光的反射率和透射率,计算了DM线的吸收系数.实验证明:由于组织结构的不同.反射率和透射率曲线随着波长的变化而变化;反射率随波长增加而增加.但增加的幅度小于透射率增加的幅度;处于紫外区的大多数波段照射组织并不能透过 光窗的下限位于400nm;吸收系数K是一非线性系数.实验所得数据可供激光医学和光学理疗参考。  相似文献   

9.
对光学薄膜反射率的讨论   总被引:2,自引:0,他引:2  
文章从多光束干涉的理论出发,介绍了光学薄膜的反射率并对其进行简单分析,进而说明光学薄膜作为增反膜(增透膜)应满足的条件,最后还给出了光学薄膜反射率与入射光波长之间的曲线关系。  相似文献   

10.
探讨了牛黄形成前后胆汁主要成分变化,用FTIR和ESR检测证实,培植牛黄属色素型结石.  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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