A comparison of the known SD bands in the mass A≈80 region

The mass A≈80 region is now firmly established as the newest region of superdeformation, with up to 11 nuclei exhibiting as many as 21 superdeformed bands. The dynamic moments of inertia of these bands reveal a variety of interesting features, such as superdeformed band crossings and the first pair of identical superdeformed bands in the mass A≈80 region. Cranked shell model calculations have been performed and the bands are interpreted in terms of the number of high-N intruder orbitals occupied. The differences in dynamic moments of inertia and the proposed single particle configurations are discussed.     

Line Intensities of (12)C(16)O(2) in the 1.2-1.4 µm Spectral Region

The 7000-8500 cm(-1) spectral region of (12)C(16)O(2) has been investigated using the high-resolution FT spectrometer of LPPM in Orsay. The two strongest bands in this region are the 10031 <-- 00001 and 10032 <-- 00001 bands centered at 8294 and 8192 cm(-1). Line intensities in these two bands and in the 40013 <-- 00001 and 40014 <-- 00001 bands have been measured. Using the method of effective operators, these line intensities have been included in a new fit of effective dipole-moment parameters to all available experimental data in the same spectral region of (12)C(16)O(2). The corresponding calculated line intensities of the 10031 <-- 00001 and 10032 <-- 00001 bands are compared with the experimental ones. Copyright 2000 Academic Press.     

稀土氟碳酸盐矿物的光致发光谱和吸收谱研究

测定并讨论了产自四川冕宁矿区的氟碳铈矿和产自内蒙白云鄂博稀土矿区的黄河矿、氟碳钙铈矿、氟碳铈钡矿的光致发光谱。结果表明,稀土氟碳酸盐矿物在488.0nm和514.5nm激光激发下的光致发光中心是Nd3+,发光谱中的所有谱带均出自Nd3+的辐射跃迁。在488.0nm激光激发下,稀土氟碳酸盐矿物在495nm到733nm谱区的发光谱带强而尖锐,但在514.5nm激光激发下,这个谱区的谱带明显变弱或消失,转而出现783nm到907nm谱区的强发光谱带。可见光吸收谱表明稀土氟碳酸盐矿物对可见光的吸收也与矿物中的Nd3+有关。     

Elimination of the Fluctuation in the Observed Transition Energies and Spin Assignments of the Superdeformed Bands in A≈150 Region

The spins of superdeformed bands in A≈150 region are assigned by the ah fitting provided the fluctuation are removed from the observed transition energies. Some typical superdeformed bands are discussed. For some superdeformed bands, the precision of spin assignments by the ah fitting could be improved.     

190区超形变核中转动带的组态结构

通过系统研究A～190区超形变核中转动带的转动惯量、角动量顺排、旋称分裂随转动频率的变化规律, 结合我们用处理对力的粒子数守恒方法的计算结果, 对A～190区所有转动带的组态结构给出了一个整体的描述. 绝大多数超形变带都建立在强耦合轨道上, 例如中子[512]5/2, [624]9/2. 少数超形变带则建立在高j闯入轨道上, 即中子[761]3/2, [752]5/2. 根据我们提出的组态结构所进行的理论计算结果表明, A～190区所有转动带的一般行为、反常变化和带交叉都得到了满意的解释.     

Comparison Between the Induced Changes in the Intensities of Mid and Near Infrared Absorption Bands of Poly[Vinyl Alcohol] Due to Temperature and Solvents

The temperature induced changes in the intensities of the infrared absorption bands of PVA in both MID and NIR regions are presented. The absorption band at 1141cm^-1 is the only band among the bands in the mid region which is markedly affected by temperature. This band is taken as a measure of crystallinity of PVA. PVA shows two phase transitions at 80c⁰ and 120c⁰. The absorbances of the 1940nm in the near region is also temperature sensititve. The temperature dependence of the other bands in either mid or near regions is very weak. The effect of non polar and polar solvents such as n-hexane, carbon tetrachloride, toluene, chloroform, methanol and acetone is discussed. Comparison between the solvent induced changes in the intensities of the bands in mid and near regions is carried out. The data demonstrate that the bands in the near region ( overtone and combinations) are more sensitive to solvents than the bands in the mid regions. The combined effect of temperature and solvents on the intensities of absorption bands of PVA is also studied.     

Structure comparison of Orpiment and Realgar by Raman spectroscopy

Raman spectroscopy was used to characterize and differentiate the two minerals, Orpiment and Realgar, and the bands related to the mineral structure. The Raman spectra of these two minerals are divided into three sections: (a) 100–250?cm^?1 region attributed to the sulfur–arsenic–sulfur bending vibrational modes; (b) 250–450?cm^?1 region due to the arsenic–sulfur stretching vibration; and (c) 450–850?cm^?1 region assigned to overtone and combination bands. A total of 14 Raman bands for the spectrum in the 1600–100?cm^?1 region were observed. The significant differences between the minerals Orpiment and Realgar are observed by Raman spectroscopy. Realgar shows the typical bands observed at 340, 268, 228, and 218?cm^?1, and the special bands at 379, 289, 200, 176, and 102?cm^?1 for Orpiment are observed. The additional bands in 850–450?cm^?1 region are only observed for the mineral Orpiment, which may be attributed to overtone and combination bands in the Raman spectrum. The variation in band positions is dependent upon the structural symmetry, arsenic–sulfur bond distances, and angles. Moreover, another cause for the difference is the effect of the intermolecular forces and to the strong coupling between close lying external and internal modes. The difference of these two minerals structure induce tremendous diversity on Raman spectra, so Raman spectroscopy offers the information on the molecular structure of the minerals Orpiment and Realgar.     

Absorption spectrum of the HCCO radical

In the flash-photolysis of oxazole and isoxazole, new transient absorption bands are observed in the region 3080–3670 A. Vibrational analysis of these bands showed that they can be arranged into two electronic systems with their origin bands at 3333.60 A and 3367.01 A. Based on the experimental conditions under which the bands are produced and on the analysis of their vibrational and gross-rotational structure, these bands are assigned to a new carrier, the HCCO free radical.     

Electronic Bands of the BeOH and BeOD

The electronic bands appearing in the region 300–330 nm were produced in a low-pressure DC are with beryllium electrodes. The bands were obtained in the atmosphere of ordinary water vapour and heavy water vapour. From isotope shift studies, experimental conditions and the similarity with the bands of isoelectronic BeF, the emitting molecules were identified as BeOH and BeOD, respectively.     

NO2分子519～524 nm区的激光诱导荧光激发谱

实验测定了室温下NO2分子在519～524nm区域的高分辨激光诱导荧光激发谱,标识了25个振动带,并作了转动分析,确定了这些带的带源、转动常数以及旋-转偶合常数等分子常数,其中有8个振动带是新发现的,对振动带的转动结构分析表明,所有得到转动标识的谱线均属于平行跃迁2B2-2A1,其中上振动能级具有B2对称类是由于电子激发态2B2与电子基态的振动能级之间的强烈相互作用所致。     

奇A 核的多声子γ振动带实验研究进展

对于近年来清华大学与美国合作研究组在原子核结构实验研究中有关奇A 核的多声子 振动带方面的进展进行了评述。研究人员通过有效的国际合作,识别了质量数A = 100 丰中子核区的奇A核103Nb,105Mo,107Tc 和109Tc中的两声子 振动带,这是迄今为止国际上在奇A 核的结构研究中发现的仅有的4 例这样的结构。对于实验方法、研究结果以及这些多声子 振动带的特性进行了评述,并对目前在多声子带其他方面的研究及今后进一步的工作进行了概述。The experimental research on multi-phonon γ-vibrational bands in odd-A nuclei by our international collaboration has been reviewed. The two phonon -vibrational bands in 103Nb, 105Mo, 107Tc and 109Tc in the A = 100 neutron-rich nuclear region were identified, which are the only four such bands discovered in nuclear structure studies until now. The experimental methods and results are summarized, and the characteristics for these band structures are discussed. The other aspects for our research on the multi-phonon vibrational bands as well as our future research work are also briefly reviewed.     

Octupole correlations in the actinides and the spdf-IBA model

The octupole bands in the Z～88, N～134 region, with their abundance of experimental information, offer a real challenge for different nuclear structure models. In this region, quasimolecular bands, which are thought to indicate the presence of stable octupole deformation, have been observed. The quantities most often reported are the B(E1)/B(E2) branching ratios from these levels. The calculations in the framework of the spdf model show that the 1-pf boson limit (dipole-octupole vibrations) can describe the essential experimental features related to the octupole bands in the Rn-Th region.     

磷烷1 950～2 480和3 280～3 580 cm-1波段FTIR吸收光谱强度研究

磷烷分子的基频和低泛频吸收谱线强度在对该分子定量检测应用以及天文观测中是基本的参考数据。文章探讨了高分辨傅里叶变换光谱方法研究气体样品吸收线型的基本原理,并通过实验测量以及程序拟合谱线线型,得到了磷烷分子在1950~2480cm-1波段的5个吸收带以及3280~3580cm-1波段的4个吸收带中的1760条谱线线强度,经分析其结果误差在±6%左右。     

The Vibrational and Rotational Motions Model of Nucleus(Ⅲ) Study of Superdeformed Bands in A～190 Region

The rotational spectra formula for superdeformed bands is derived from the cranking Bohr-Mottelson Hamiltonian proposed by us.Level spins and transition energies of 24 superdeformed bands in the A～190 region are studied with this formula.The obtained results are satisfactory.     

Description of the Superdeformed Bands of the Odd-Odd Nuclei in A～150 Region

With the supersymmetry scheme including many-body interactions, the global property and the ΔI=4 bifurcation in the superdeformed (SD) bands of odd-odd nuclei in A～150 mass region are investigated systematically. Good results for the γ-ray energies, the dynamical moments of inertia, and energy differences ΔE_γ-ΔE_γ^ref are obtained. It shows that this approach is quite powerful in describing not only the SD bands in even-even and odd-A nuclei but also those in odd-odd nuclei in the mass region.     

罗谢尔盐的振动光谱

本文主要讨论了罗谢尔盐的结晶水的振动光带。把在3200—3600cm^-1范围内所观察到的四个光带分别归属为四个非等效的水分子的振动频率(v₁),从而指出在罗谢尔盐中并不存在所谓“短”的氢键的。     

The colouration of CaF 2 crystals by keV AND GeV ions

CaF 2 crystals have been implanted with a variety of ions of widely different energies and mass. Effects have been monitored using optical absorption in the range 120-750 v nm. This includes the vacuum UV region. For 100 v keV ions (Al, Mg, Kr) we observe extrinsic colloid bands in the case of implanted metal ions at high fluences (10 17 v ions v cm 2 ) but no colour centres (F, F 2 etc). For GeV ions (U, Ni) we observe prominent absorption bands in the visible region at fluences of 10 12 v ions v cm m 2 attributed to extrinsic calcium colloids. New optical features are discussed including an absorption band near 185 v nm in the VUV and bands at 604 v nm and 672 v nm in the visible region.     

Re-discussion of the Spin Assignments of the Superdeformed Bands in A≈190 Region (Ⅱ) Odd Superdeformed Nuclei

The influence of the I=1 staggering and the fluctuation in observed γ-tyanstion energies on the spin assignments of superdeformed bands is taken into account properly. An improved approach for removing the fluctuations from the observed y transition energies is proposed. The smoothed transition energies are fitted by the ah expression or its modification to assign the spins of the superdeformed bands in the odd-A nuclei in A≈190 region. The assigned spins for some superdeformed bands are different from those given in other approaches.     

二次微分和傅里叶解卷积技术的表观分辨率研究

二次微分和解卷积技术都可以提高红外光谱的表观分辨率 ,从而可以分辨谱图中重叠的峰。文章用二次微分和解卷积技术对 2 十二烷基TCNQ ,2 十五烷基TCNQ和 2 十八烷基TCNQ的红外光谱进行了处理 ,发现CH2 反对称和对称伸缩振动区域的两对吸收峰的强度与脂肪链的长度有关 ,并从实验上证实了解卷积技术比二次微分技术具有更强的表观分辨能力     

Anisotropic p−ƒ mixing mechanism explaining anomalous magnetic properties in Ce monopnictides

Anomalously small crystalline field splitting in the paramagnetic region and extremely strong magnetic anisotropy in the ordered phases in CeSb and CeBi are explained based on the anisotropic mixing mechanism between the 4? states and the valence bands. In the paramagnetic region, the mixing gives the effective crystalline field splitting which is estimated to cancel the splitting of the point charge model in good agreement with experiment. The anisotropy energy of CeSb calculated by using the realistic valence bands is consistent with the strong anisotropy observed experimentally.