用多种谱仪技术研究环氧丙烷点火的微观特性

利用OMA(光多通道分析系统)谱仪和单色谱仪技术研究了环氧丙烷冲击点火的微观特性.OMA谱仪观察到O,CH2O,C2,CH,CH3O,CO2,H2O等许多中间产物和最终产物.利用三台单色谱仪和压力传感器确定环氧丙烷冲击点火后这些产物出现的顺序并确定了它们的点火延迟时间和临界条件.     

Spectroscopic Studies of Chemical Reactions in Strong Shock Waves

Shock tube provides a promising tool of studying high temperature chemical reaction in gases. The heating by shock wave is uniform, extremely fast and intense. So that the temperature may rise thousands of degrees in a fraction of a second. Observations of the effects of this heating on C₆H₆ has shown extensive decomposition into C₂ and CN.     

New Bands in the Shock Excited NbO Blue/Visible and Near Infrared Systems

Abstract

Band systems of the astrophysically important molecule Niobium Oxide (NbO) have been excited in helium-driven shock waves through argon containing powdered Nb₂O₅. Of the 25 bands of the Δv = +3, +2, +1,0, -1, -2 and -3 sequences of the C ⁴Σ^? – X ⁴Σ^? blue/visible system which were excited between 4220Å and 5608Å, 16 are newly reported here. The Δv = +3 and -3 sequences are completely new. 12 new bands were also excited in the near infrared region 7952Å - 8450Å.     

高里德堡态氢原子与氦原子散射的高分辨研究

利用了氢原子飞渡时间谱实验方法对处于高n主量子数里德堡态的氢原子与氦原子的分子束散射过程进行了高分辨研究.测量了H(n)+He→H(n′)+He散射过程的散射微分截面.实验结果表明,产物主要分布在前向散射方向,在侧向也有一定的分布.在前向和侧向存在大量的振荡结构.同时详细的研究也表明,在上述的散射过程中往前散射的方向上,氢原子里德堡态主量子数n的变化并不是很大.实验结果得到了为理论上精确研究高n主量子数里德堡态的氢原子与氦原子的散射动力学的一套精细的实验数据.     

冲击压缩状态下液态一氧化碳和氮混合物的发射光谱

利用二级轻气炮驱动铜飞片以2.21 km·s-1的速度撞击铝合金低温靶,产生速度为18.76 km·s-1的一维冲击波作用于等比例冷凝的一氧化碳和氮均匀混合液体样品.同时,借助增强光电耦合传感器及瞬态摄谱技术捕获到冲击压力为33.5 GPa下样品完全离解成等离子体时的线状光谱.分析这些数据可知,文章所述的六通道光谱系统能可靠地测量和记录介质的冲击压缩一发光过程;其中主要产物的发射谱线表明,一氧化碳和氮均质体已经发生了化学反应和相变.此外,与中心波长较高的谱线强度相比,488 nm通道的光谱强度明显较高的事实,也证明高密度碳氢液体在冲击压力作用下确实存在从"光学薄"到"光学厚"的转变.     

Nd_2O_3纳米粉的拉曼光谱研究

测量了 Nd2 O3纳米粉的拉曼谱 ,发现随着颗粒尺寸的减小 ,其拉曼谱峰发生红移 ,同时谱峰发生不对称变宽 ,并用量子尺寸效应对这种现象进行了解释     

碘分子高激发态光学双共振多光子离化光谱

本文利用双色双共振多光子离化技术（ＯＯＤＲ－ＭＰＩ）,对Ｉ２分子离子对态Ｆ０＋ｕ态进行了较为仔细的研究,利用已知的分子常数,对所得谱线进行了标识和归属,将Ｔｅ＝５２４００ｃｍ－１,间隔为３７ｃｍ－１的振动序列归属为Ｆ０＋ｕ态的高振动激发态,并确定了多光子激发及离化的跃迁通道     

High resolution molecular spectroscopy in the submillimeter region

Fourier Transform laboratory measurements have been carried out, for the first time in the 8–85 cm^–1 spectral region, with an unapodized resolution of 3.3. 10^–3 cm^–1 and a frequency accuracy of 2. 10^–4 cm^–1. Samples from spectra of several molecules namely: CO, O₃, H₂O₂, NO, NO₂, HNO₃, SO₂, H₂S, HOCL, NOCL, HNCO, ND₃ and AsH₃ are presented to show both the quality of the measurements and the type of information supplied by high resolution spectroscopy in the submillimeter region.     

多极板电流变阀应用于避震器之研究

以流动模式（flow mode)多极板之电流变阀（electrorheological valve)进行避震器阻尼力特性的研究。由于电极板的大小直接影响到流体流动的剪力及避雷器的阻尼力,因此使用多极板型式来探讨避震器的特性。设计有1－5个流道之并联及1－3个流道之串联多极板电流变阀的电流变避震器,并使用自制的电流变液进行实验。由研究结果显示,流动式并联极板之电流变避震器,一个流道之阻尼力最大,流道极板增加则阻尼力反而下降,而流动式串联多极板之电流变避震器之阻尼力则随极板数递增,故需要高阻尼力之避震器较适合使用串联多极板型式。     

Infrared Spectra of Benzene at High Pressures

Mid-infrared spectra in the ranges 400-1800 and 2700-4000 cm^-1 are reported for benzene samples in diamond anvil cells at ambient temperature and pressures up to 10 GPa. The freezing pressure is confirmed to be 0.1±0.05 GPa. Changes in the spectra and in the sample appearance indicate that sluggish solid state phase transitions occur near 2.0 and 4.0 GPa. The wave number shifts with pressure for 27 selected peaks are plotted. Their small increases show that only minor distortions of the molecules occur, and there is no evidence of any weakening of intramolecular bonds in this pressure range.     

JP-10点火延时的激波管研究

在预加热激波管上测定了JP-10的点火延时时间．采用高精度真空仪直接测定注入激波管中JP-10蒸气压力，获得了JP-10气相浓度，解决了高碳数碳氢燃料点火延时激波管实验时管壁吸附影响燃料气相浓度确定的困难．采用压力传感器、单色仪和光电倍增管记录得到了完整的点火过程引起的压力变化和OH或CH自由基发射强度变化．自由基发射信号作为诊断点火发生的手段．当实验压力为151?556 kPa，温度为1000?2120 K，JP-10摩尔百分比为0.1%?0.55%，化学当量比为0.25、0.5、1.0、2.0时，获得了点火延时时间与实验温度、JP-10浓度、O2浓度的依赖关系，结果还表明，高温区和低温区呈现出不同的依赖关系．     

高温非平衡条件下氟原子亲电动力学的激波管研究

用激波管方法研究了氟原子亲电动力学.利用反射激波加热获得离子化气体,随后经冷却速度达106K/s的强稀疏波冷却,离化气体将经历以电子复合为主的非平衡过程.用Langmuir静电探针监测反射激波后离子浓度随时间的演变,分析了探针工作状态,引入了探针鞘层内的弹性散射修正.测定了温度在1200～2200K以氩气为碰撞第三体的F原子与电子复合速率系数,讨论了温度依赖关系.     

Multiple-Photon Dynamics in Molecules: A New Approach to High Resolution Spectroscopy of Highly Excited Vibrational States

Multi-photon transitions with two simultaneously interacting IR laser fields lead to final excited states with frequenciesnν = n₁ν₁+ n₂ν₂, withnthe total number of photons absorbed and (n,n₁,n₂) = (2, 1, 1), (3, 2, 1), (4, 1, 3), etc. The nature of the actual transition is determined by shift measurements, where the lasers are frequency-tuned by δν_iin opposite directions keeping the sum frequency,nν, resonant with the molecular transition. This technique opens a new spectral range for multi-photon transitions and a unique identification of the observed features. Forn₁andn₂both positive the excitation will lead to a “normal” up–up multi-photon transition. Many three- and four-photon transitions in the ν₃vibrational ladder of SF₆could be resolved with a resolution of 1 MHz, as well as four new two-photon transitions. As long asn₁+ n₂≥ 0, one of the twon_imay be negative resulting in an, e.g., up–down excitation pathway with its particular selection rules. The up–down excitations are demonstrated both for one- and two-photon transitions using the frequency shift technique. The different possible excitation schemes which meet the resonance condition for these transitions lead to interference effects and local couplings to highly excited states. Changes in resonance frequency for a one-photon transition (n= 1), due to these effects, are demonstrated. Evidently, the radiative coupling of participating levels to high-lying or quasi-continuum states may drastically change for different δν_ileading both to ac Stark shift and transition probability variations.     

高光谱分辨率横向剪切静态干涉光谱仪

提出一种基于新型的分光方法的横向剪切分束器,分析了该分束器结构的分光原理,并对其用于干涉光谱仪中的效果进行了分析计算.该分束器同体积条件下较目前的分束器可以产生十倍以上的剪切量,应用到干涉仪中可以在获得高光谱分辨率的同时不增大仪器的体积和重量.同时,该分束器分光时,无光能返回光源,较Sagnac型分束器对光能的利用率提高了近一倍;相对变形Mach-Zehnder型结构易实现实体化.     

亚甲蓝聚合体的吸收光谱及聚合状态的研究

本文用环己烷作萃取剂，从亚甲蓝的阴离子表面活性剂水溶液中将亚甲蓝二聚体萃取至有机相，测定其紫外－可见吸收光谱，最大吸收波长为604nm，摩尔吸光系数为8.74×10^4L·mol^-1·cm^-1；通过差示光谱推算构成二聚体的单分子倾角（α）为49.7°。计算出水溶液中亚甲蓝二聚体的聚合常数为2.487×10^4。     

高纯度烟草过氧化物酶（TOP I）光谱特性研究

采用交换吸附脱色及柱层析新技术，成功地从烟叶中分离和纯化了一种烟草过氧化物酶同工酶(TOP I)，并对其进行了一系列光谱特性研究。基质辅助激光解吸电离飞行时间质谱(MALDI-TOF-MS)测得TOP I分子量为21888．5，等电点pI为3．5；氨基酸组成分析表明TOP I为一含血红素的酸性蛋白酶。光谱学分析揭示，在402nm处有一典型的Soret带，在498和636nm处有特征吸收峰(α，β带)，酸度和变性剂对TOP I在紫外可见区的特征吸收峰均产生一定的影响，TOP I的荧光光谱测定结果说明TOP I分子中含有Trp残基和Tyr残基以及其自身的独特的光谱学特性。     

二氧化锡气敏纳米粉体的红外光谱研究

采用溶胶-凝胶法制备了纳米级SnO2,利用XRD和IR光谱对其晶化过程进行了详细研究。结果表明,硝酸胶溶有利于SnO2纳米晶的生成,676和545cm-1处的红外吸收分别为二氧化锡中Eu型对称的Sn-O的伸缩振动和A2u型对称的O-Sn-O变角振动,且随着纳米粉体热处理温度的升高,峰形窄化,A2u型的变角振动峰强度降低。     

Franck Condon Factors for the He(I) Photoelectron Spectrum of Methyl Radical

Computed Franck Condon factors pertinent to the photoelectron spectrum of methyl radical are discussed. The low frequency spacings in the observed spectra are assigned to transitions between the first and second (bending mode, v ₂′) excited states and thus correspond to differences in the bending frequencies of the cation and the radical. The high frequency spacing is assigned as 2v ₂′ of the cation. Any barrier to planarity of the radical is lower than the zero point energy of the bending mode.     

射流冷却的OCS分子高分辨VUV吸收光谱研究

以双光子共振四波混频差频产生的高分辨、可调谐真空紫外激光(VUV)为光源,在151～156nm内测量了超声射流冷却的OCS分子1Σ+-1Σ+电子跃迁带的吸收光谱.由于采用射流冷却和高分辨激光,得到与前人吸收谱测量结果不同的光谱线线形,观察到两个呈现明显非对称结构的振动峰,通过Fano线型拟合,获得了这两个振动峰的半高峰宽和非对称参数q值,与前人光碎片激发谱测量结果基本一致.实验中,为了消除VUV激光强度波动的影响,通过记录参比光的方法,有效地提高了吸收光谱的信噪比,使得吸收测量的灵敏度达到1%左右.     

一个高时间分辨的多间隙电阻板室原型

研制了一种多气隙电阻板室原型并建立了相关的测试系统.利用宇宙线测试系统和欧洲核子中心的试验束装置T1?0对其性能进行了测试,给出了初步结果.时间分辨达到70ps,对最小电离粒子的探测效率大于95%.