光纤共振和预共振喇曼光谱(英)

在液芯光纤内产生共振和预共振喇曼效应，喇曼光谱强度可以大幅度提高，最高可达109倍．本文介绍获得光纤（预）共振喇曼光谱的可行性、实验及实验结果．用远离吸收带的激光激发获得了α甲基吡啶预共振喇曼光谱．用小功率激光（0．8mW）、低浓度溶液（9．6×10(-12)mol／L）还获得了β叶红素在CS2中的共振喇曼光谱．     

OMA控制与探测的激光共振喇曼谱仪

本文介绍了一套脉冲染料激光器激发，带增强型二极管阵列探测器探测的ＯＭＡ共振喇曼光谱仪（ＯＭＡＲ２Ｓ）可测量样品物质的共振喇曼光谱及时间分辨的共振喇曼光谱（ＴＲ３）。对ＣＣｌ４样品进行了分析，其结果与标准谱符合得很好。测试和分析了谱仪的主要参数。在使用１２００ｇ／ｍｍ的光栅时，谱仪在５９０２处分辨率△ｖ为６．７ｃｍ－１；在６３２８处，△ｖ＝５．０ｃｍ－１，杂散光为４．８×１０－３；波长精度好于±１；重复性好于０．７；光谱工作范围从３８００到１５０００。     

光纤共振和预共振喇曼光谱

在液芯光纤内产生共振和预共振喇曼效应,喇曼光谱强度可以大幅度提高,最高可达10⁹倍.本文介绍获得光纤(预)共振喇曼光谱的可行性、实验及实验结果.用远离吸收带的激光激发获得了α甲基吡啶预共振喇曼光谱.用小功率激光(0.8mW)、低浓度溶液(9.6×10¹²mol/L)还获得了β叶红素在CS₂中的共振喇曼光谱.     

皮秒激光瞬态受激光喇曼散射的实验研究

本文采用对撞脉冲锁模Ｎｄ：ＹＡＧ激光器输出１０ｐｓ脉冲串，经ＫＴＰ非线性晶体腔外倍频，泵浦喇曼介质为二甲亚砜（ＤＭＳＯ）液体。实验研究了不同透镜焦长，焦点位置不及不同喇曼介质长度对瞬态受激喇曼散射的影响，获得了能量转换效率分别为４５．６％和１０．５％的前，后和同阶斯托克斯－喇曼射光，，并以实验结果进行了讨论。     

低温下ZnSe－ZnS多量子阱的光致发光光谱和喇曼散射谱

本文报导了２Ｋ下，在ＧａＡｓ（１００）衬底上用ＭＯＣＶＤ方法生长的ＺｎＳｅ－ＺｎＳ多量子阱材料的光致发光光谱和喇曼散射谱．用共振激发、共振喇曼和共振瑞利散射等方法对各发光谱带和喇曼散射峰的来源和机制进行了鉴别．     

蛋白质结构和功能的紫外共振喇曼光谱研究

紫外共振喇曼光谱技术是研究复杂大分子结构的有力工具。结合作者在美国Pittsburgh University期间所做的工作，介绍了用紫外共振喇曼光谱研究肽和蛋白质结构与功能的现状和进展，N-methylacetamide和glycyglycine水溶液光化学异构过程的紫外共振喇曼光谱研究，简述了紫外共振喇曼光谱实验技术要点。本文还跟踪国际最新研究成果，介绍了利用紫外共振喇曼光谱技术研究蛋白质的折叠和去折叠过程。     

有机纳米分子聚集体PIC-I的Raman光谱研究

本文从分子聚集体ＰＩＣ－Ｉ的吸收光谱可观测到Ｊ－带的红移和窄化,并可算出１３６８ｃｍ－１振模,以及本实验条件下聚集体单体数目为Ｎ≈３链长为３×０．３ｎｍ＝０．９ｎｍ。测量了ＰＩＣ－Ｉ聚集体的荧光光谱,将它与吸收光谱相比较可以看出,聚集体吸收带（５７２．５ｎｍ）和荧光发射带（５７２．５ｎｍ）是共振的。系统地研究了ＰＩＣ－Ｉ聚集体的喇曼光谱（１００～１８００ｃｍ－１）,验证了振动模 １３６８ｃｍ－１的存在。     

低温下ZnSe-ZnS多量子阱的光致发光光谱和喇曼散射谱

本文报导了2K下,在GaAs(100)衬底上用MOCVD方法生长的ZnSe-ZnS多量子阱材料的光致发光光谱和喇曼散射谱.用共振激发、共振喇曼和共振瑞利散射等方法对各发光谱带和喇曼散射峰的来源和机制进行了鉴别.     

相干喇曼散射光谱中干涉效应及偏振特性的研究

本文测量了苯及一些苯衍生物在不同偏振配置下的相干喇曼谱(CARS和CSRS),分析了喇曼共振与双光子吸收共振的干涉作用对光谱线型的影响以及喇曼模的偏振特性与分子振动对称性的关系.     

结晶紫、碱性品红、染料1555吸附在银胶上的表面增强喇曼散射的激发波长关系

本文通过研究在不同激发波长下吸附在银胶上的结晶紫、碱性品红、染料1555的表面增强喇曼散射散射强度的变化,分析了普通喇曼散射、表面增强喇曼散射及表面增强共振喇曼散射之间的联系与不同。     

Mossbauer, Raman and X-ray diffraction studies of superparamagnetic NiFe2O4 nanoparticles prepared by sol-gel auto-combustion method

Superparamagnetic nickel ferrite single phase nanoparticles with the average crystallite size of ∼9 nm have been synthesized at a low temperature (220 °C) by the sol-gel auto-combustion method. In the present study the as prepared powder was further calcined at different temperatures for 4 h, resulting in nanoparticles of larger size. The nanoparticles exhibited superparamagnetic behavior and changes in cation distribution as revealed by the Mossbauer, Raman and X-ray diffraction studies. The Mossbauer spectra collected at 5 K and under 5 T applied magnetic field showed mixed spinel structure and canted spin order for the nanoparticles, whereas there is collinear spin order with inverse spinel structure for larger particles. The vibrational spectra of the nanoparticles showed a redshift and broadening in the Raman line shape due to confinement effects.     

HRTEM and Raman study of onion-like fullerenes encapsulated Fe

Onion-like fullerenes (OLFs) encapsulated Fe have been synthesized by chemical vapor deposition (CVD). The samples have been characterized by HRTEM and Raman methods. The diameters of OLFs encapsulated Fe are in the range from 15 to 40 nm with pure Fe particles. HRTEM and Raman spectra show that OLFs are highly graphite. XRD spectrum shows Fe nanoparticles are protected in OLFs and are not oxidized by air. It is the stain of graphene shells and the uneven size of OLFs encapsulated Fe that causes the Raman spectra to shift downward slightly from 1580 cm⁻¹.     

一种具有较强表面增强拉曼散射效应的纳米银的特性

对一种具有较强表面增强拉曼散射效应的纳米银 ,进行了透射式电镜、吸收谱及稳定性测定 ,发现按同一方法在不同时间制备的胶态纳米银粒度分布均匀 ,粒径均为 5nm ,吸收谱除在 43 0nm处有一吸收峰外 ,在 2 1 0nm处还有一尖锐的吸收峰 ,室温下放置 7个月后仍具有较强的SERS活性。     

The structural and optical properties of gallium arsenic nanoparticles

Spherical gallium arsenic nanoparticles prepared by thermal evaporation method have been fabricated successfully. The structural and optical properties of GaAs nanoparticles are studied in detail. It is found that while the growth pressure rises from 0.4 to 5 Torr, the average size of GaAs nanoparticles increases from 6 to 12 nm and standard deviation keeps almost the same (2 nm) except for 0.5 Torr. By using transmission electron microscopy and Raman spectra, a critical preparation condition has been found which characterize the amorphous to crystal transition of GaAs nanoparticles.     

Optical properties of La2O3 doped diamond-like carbon films

A novel kind of La₂O₃ doped diamond-like carbon (DLC) films with thickness of 100-120 nm were deposited by unbalanced magnetron sputtering. Raman spectra and photoluminescence properties were measured by Raman spectrometer operated by 325 nm He-Cd laser and 514 nm Ar⁺ laser, respectively. The intensities of Raman spectra and photoluminescence are higher than those of pure DLC films. The La₂O₃ doped DLC films have the potential promising for the application of solar cell coatings.     

Study of porous silicon structure by Raman scattering

In this paper, the effect of etching time on light emitting porous silicon has been studied by using Raman scattering. Enhancement of Raman intensity by increasing the porosity is observed. Also there is a red shift, about 4 cm⁻¹, from the Raman peak of crystalline silicon to that of porous silicon. The phonon confinement model suggests the existence of spherical nanocrystalline silicon with diameter around 7 nm. But SEM images show that the samples have a sheetlike structure that confines phonons in one dimension. This should not cause any shift in their Raman spectra. It is suggested that the observed Raman peak shift is due to the spherical nanocrystals on the surface of these sheets.     

"冰毒"拉曼散射振动模式的研究

利用显微拉曼技术对致幻药物－“冰毒”做了测试分析研究。在激发光５１４．５ｎｍ和室温环境下,得到了“冰毒”分子的拉曼散射谱。根据两种分子同属单取代苯类,具有Ｃｙ２ｖ对称性,对安非他明和甲基安非他明分子的拉曼振动模式进行了识别。只出现在甲基安非他明拉曼谱中的２４５９ｃｍ＾－１谱线,是其他毒品分子拉曼谱中都湍有的,我们认为极可能是Ｃ－Ｎ＾＋－Ｃ之间的伸缩振动。     

Investigation of halloysite nanotubes with deposited silver nanoparticles by methods of optical spectroscopy

Halloysite nanotube composites covered by silver nanoparticles with the average diameters of 5 nm and 9 nm have been studied by methods of optical spectroscopy of reflectance/transmittance and Raman spectroscopy. It has been established that silver significantly increases the light absorption by nanocomposites in the range of 300 to 700 nm with a maximum near 400 nm, especially for the samples with the nanoparticle size of 9 nm, which is explained by plasmonic effects. The optical absorption increases also in the long-wavelength spectral range, which seems to be due to the localized electronic states in an alumosilicate halloysite matrix after deposition of nanoparticles. Raman spectra of nanocomposites reveal intense scattering peaks at the local phonons, whose intensities are maxima for the samples with the silver nanoparticle sizes of 9 nm, which can be caused by plasmonic enhancement of the light scattering efficiency. The results show the ability to use halloysite nanotube nanocomposites in photonics and biomedicine.     

稀土化合物Raman谱中荧光带的辨认

研究了三价稀土氧化物及退火结晶褐钇铌矿和褐铈铌矿在４８８０和５１４５ｎｍ激光激发下所得Ｒａｍａｎ光谱中的荧光带。结果表明,在这两种激光线激发下,Ｓｍ３＋、Ｅｕ３＋和Ｅｒ３＋的荧光对稀土化合物的Ｒａｍａｎ光谱有很大干扰。提出几种在稀土化合物Ｒａｍａｎ光谱中辨认荧光带的方法。     

激光等离子体受激Raman散射光谱的时间分辨测量

采用光学多道谱仪和光学条纹相机耦合,组成时间分辨的Raman散射光谱测量系统,可实现0.5nm的光谱分辨和好于10ps的时间分辨。采用该测量系统,在神光Ⅱ装置上开展了脉宽1ns、波长351nm的激光与两种不同尺寸柱腔靶相互作用的物理实验,获得了时间分辨的SRS光谱实验结果。研究表明,SRS光谱在时间上相对于入射激光有一定的延迟,腔靶尺寸减小时,延迟时间随之减小。通过长、短波截止波长分析电子密度方法,计算得出了Ⅰ型和Ⅱ型腔靶SRS散射光最短波长光谱发生的密度区分别为0.069nc和0.027nc。