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1.
测量了CCl_4,CH_2Cl_2和CHCl_3对生物膜中磷脂酰胆碱作用的紫外电子吸收光谱,实验结果表明,由于CCl_4,CH_2Cl_2和CHCl_3分子结构的差异,三种溶剂的极性依次递增,磷脂酰胆碱π-π ̄*电子跃迁的吸收峰红移。磷脂酰胆碱在CCl_4中光谱呈单吸收峰,在CH_2Cl_2和CHCl_3中光谱特征呈双蜂结构,存在聚集体的激子态跃迁,由此给出了脂质分子聚集状态的光谱依据。  相似文献   

2.
对草酰氯分子的多键解离方式进行理论和实验的研究。计算表明,草酰氯的第一电子激发态增强了C-C键而削弱了C-Cl键,解离出Cl原子和ClCOCO自由基。在351nm光解实验中观察到中间物ClCOCO的红外发光。该中间物很容量进一步热解为ClCO和CO,势垒仅为0.4eV。第二电子激发态形成C-C较强的反键轨道,造成C-C键的解离而产生ClCO,在248nm光解实验中,产生了振转激发的终产物CO。以瞬  相似文献   

3.
兰荣清 《应用光学》1996,17(6):31-33
本文简述可编逻辑器件的性能特点,介绍了用可编程逻辑器件设计星载线阵CCD相机CCD驱动器的方法,减少了驱动器的体积,降低了功耗,实现了驱动器的更新换代。  相似文献   

4.
本工作采用光学发射谱方法测量了TEA CO2脉冲激光辐射SiH4+CH4系统产生的等离子体反应过程中的发射谱特性,探测到了Si,Si^+,Si^2+,C,C^+,C^2+,CH,SiH,SiH^+,Si2和H的特征辐射,研究了含C,Si碎片粒子光谱随实验条件的变化规律,并讨论了反应条件对OES的影响。  相似文献   

5.
亚稳态分子CO(α^3П)猝灭过程   总被引:3,自引:1,他引:2  
用流动余辉技术测定了亚稳态分子CO(α^3П)被CS2,SO2,SO,NOC12,IC1,SO2C12,SC12,H2O,CHC13,CH2C12,He和Ne猝灭的速率常数,并较为详细地讨论了CO(α)和CS2,SO2,SO,NO等分子的猝灭反应的可能出口通道,指出CO(α)被其他分子猝灭时,主要出口通道是化学反应,E-E和E-V能量转移,有时是几种不同的出口通道同时存在。  相似文献   

6.
本文用激光光解-荧光猝灭方法测定了CH3Cl对CH(A,B和C)及CH2Cl2、CHCl3和CCl4对CH(C)的猝灭速率常数。结果表明,氯代甲烷分子对CH(C)的猝灭速率常数近似于CH(B)的猝灭速率常数,而比CH(A)的猝灭速率常数大,但都具有与气动速率相当的量线,表明化学反应在其中可能起着重要的作用,且CH(A,B,C)的猝灭速率常数都随氯代甲烷分子中的C-Cl键数的增加而增大。我们用碰撞络  相似文献   

7.
利用分子束和飞行时间质谱技术研究了激光烧蚀金属Al原子与4种不同的卤代甲烷:CCl4,CF3Cl,CF3Br,CF4的气相反应,由激光电离飞行时间质谱检测的结果表明,Al与CF3Cl反应生成AlCl,而与CF3Br反应生成AlBr,与CCl4及CF4反应分别生成ACl及AlF。  相似文献   

8.
CCD在光谱分析系统中的应用研究   总被引:15,自引:3,他引:12  
本文对利用CCD作传感器件进行光谱分析的方法进行了理论和实验研究。通过分析CCD的结构特点和光电特性,从理论上证明了利用CCD进行光谱分析的可行性,设计了一套适合线阵CCD的高速图像采集卡,建立了一套智能化光谱数据采集分析系统。该系统主要由光栅、CCD传感器及数据采集卡、计算机等部分组成。我们用高压汞灯作为标准光谱进行定标,得到了一个非常简单的计算光谱的数学公式。实验表明该系统具有较高的测量精度,特别适用于瞬态过程的光谱分析。  相似文献   

9.
CCD变积累控制技术   总被引:3,自引:0,他引:3  
在分析微光图像噪声特性的基础上,提出了通过对微光图像信号进行积分,抑制随机噪声的方法,发展了CCD可变积累控制技术,研制了CCD外围驱动控制和视频制式转换系统,使激光图像信号直接在CCD电荷包中进行多帧累加,有效地抑制了随机噪声,提高了低照度与低对比情况下的信噪比和灵敏度,同时避免了后续实时处理电路的高原干扰,图像质量有了明显的改善。  相似文献   

10.
新型IGCC系统研究与概念设计   总被引:2,自引:1,他引:1  
本文开拓研究新型整体煤气化联合循环(IGCC)系统。基于IGCC关键技术进展与系统综合分析新方法的研究,设计构筑出新型的IGCC系统,通过模拟分析;揭示了其热力特性,得出了一些有价值的结论。新系统效率已突破50%,有强的竞争力与发展前景,本研究成果将为研制新一代IGCC系统提供技术方案和理论分析方法。  相似文献   

11.
We have measured the absorption, fluorescence, fluorescence excitation spectra, fluorescence quantum yields, and IR Fourier-transform spectra of aromatic acids in solutions. We have considered spectroscopic particular features of benzoic acid, its hydroxylated and methoxylated derivatives. Using quantumchemistry methods, we have calculated and interpreted electronic spectra. Data of calculations have been compared with experimental results. We have ascertained the main channels and mechanisms of photophysical relaxation processes in the molecules under study. Proton-acceptor properties of molecules of aromatic acids have been evaluated. We have analyzed in detail mechanisms by which hydrogen bonds are formed, intramolecular charge redistribution is realized, and the electron density of oxygen atoms changes. Spectroscopic indications of participation of oxygen-containing groups in intramolecular interactions and in intermolecular interactions with the formation of cyclic dimers have been revealed.  相似文献   

12.
根据反应边界层理论,解析热解表面传热传质过程,依据热厚固体内部温度分布,给出其热解表面传质数B-number函数以及热解模型。并以4 mm厚PMMA平板为对象,进行不同送氧量和不同车速燃烧实验,通过记录火焰长度、火焰距离热解表面的高度、蔓延速度、质量损失率以及底板温度等数据,推演热解表面热通量,表面传质数等热解动力学参数的变化规律,研究结果为解释热厚固体表面燃烧的发生、发展以及状态转条件奠定理论基础。  相似文献   

13.
冯端 《物理》2006,35(11):893-896
文章概述了作者于1946-2006年期间在中央大学-南京大学物理系执教的经历,漫谈了教书、读书和写书的一些体会,介绍了在科学研究、人才培养和教材建设方面的若干成果。  相似文献   

14.
将导体球放到匀强电场中,研究电势和电场各分量的分布规律,是一个典型的电动力学问题.详细推导了极坐标和直角坐标系中的电势公式,求出了电场强度的表达式,推导电场线的方程,将公式无量纲化,应用MATLAB画出了电场强度的分布曲线和电场线以及等势线,充分反映了电场分布的规律.附录中列出了两个相关程序,可供读者参考.  相似文献   

15.
In this study, thermodynamic instabilities in hydrogen-helium fluid mixture have been analyzed. These kinds of investigations are inevitable for indicating hydrodynamic transitions in Hydrogen-Helium fluid mixture. Therefore, first we have derived equation of state of mixture via Barker-Henderson statistical perturbation theory. Moreover, we have used Yiping radial distribution function in calculating perturbed terms. Via equation of state, we have calculated excess Gibbs free energy and the Gibbs free energy in the long wavelength limit. By means of this energy in hand we could estimate degree of hetero-coordination and segregations of this mixture which is a measure for defining thermodynamic instabilities. At last, these measurements have made us capable of anticipating thermodynamic instabilities and coordination of mixture in different concentrations.  相似文献   

16.
This paper presents numerical simulation of back discharge activity that is modelled at a pinhole in a dielectric layer on plane anode. First, for a given pinhole geometry, the transitions between back discharge regimes have been depicted as a mode diagram. Then, we have studied the influence of the dielectric layer thickness on the regime transitions. We have shown that increase in the layer thickness (within range of 0.02–0.2 mm) promotes the back discharge development. Finally, we have studied the influence of ‘crater configuration’. We have shown that ‘crater shape’ favours the back discharge ignition, whereas limits the resulting discharge development.  相似文献   

17.
Particle-production processes in the Coulomb field of nuclei at high energies have been considered, and the electromagnetic properties of hadrons (mesons and hyperons) have been investigated in these processes. The results of previous investigations have been summarized, and new data from the SELEX (Fermilab) and SPHINX (Institute for High Energy Physics, Protvino) facilities have been discussed.  相似文献   

18.
We have presented a discussion on the guided waves in the indefinite-medium waveguides. The characteristic equations describing TE and TM guided waves have been derived. Aiming mainly at the TE guided waves, we have analyzed the existence conditions for the guided and surface modes for four distinct cases, respectively. A number of exotic properties have been revealed in such waveguides, such as the coexistence of forward and backward modes, the absence of fundamental modes, the existence of surface modes and the relaxed requirements for waveguide core constitutive parameters. Numerical results have confirmed our analyses.  相似文献   

19.
Explosive events have been observed to occur consecutively in bursts at intermittent locations along the boundary near the opposite polarity. The aim of the present paper is to explore a possible mechanism to interpret this burst-like characteristic of explosive events. The 2D magnetohydrodynamic (MHD) numerical simulations with resistivity have been carried out to reproduce the intermittent spatial-temporal magnetic reconnection events taking place along the long, compressible current sheet. The observed density enhancements in previously published results have been verified to be associated to magnetic reconnection sites. Late observational evidences, which support present attempts, have also been found, at least in morphological evolution of the consecutive explosive events.  相似文献   

20.
The excimer vibtational relaxation have been studied in the diffusional approximation, and stationary substantially non-equilibrium populations of high vibrational levels have been found. New formulae have been derived for quantum yield of UV lasing. Taking into account the vibrational relaxation the new effect of far-IR radiation amplification in the active media of excimer lasers is predicted.  相似文献   

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