1．053μm激光在腔靶中产生的非线性过程

波长１．０５３μｍ、脉宽约１ｎｓ、能量３００～６００Ｊ激光在亚毫米的腔靶中可以产生十分丰富的非线性过程。我们直接测量了受激Ｂｒｉｌｌｏｕｉｎ散射、受激Ｒａｍａｎ散射：通过谐波间接测量了共振吸收、离子声衰变和双等离子体衰变。其中受激Ｂｒｉｌｌｏｕｉｎ散射和受激Ｒａｍａｎ散射是腔靶中的主要非线性过程，它散射掉约４０％的入射光能量。激光激发的电子等离子体波是产生超热电子的根源，产生电子等离子体波的非线性过程是受激Ｒａｍａｎ散射、双等离子体衰变、共振吸收和离子声衰变。其中受激Ｒａｍａｎ散射是激发电子等离子体波的主要过程，它产生约占入射激光能量１０％的超热电子。各非线性过程发射的光谱与激光参数和等离子体状态有密切关系，仔细测量和研究这些谱的特性可以获得等离子体温度、密度的信息。     

碳酸脱水酶去卷曲构象的FT-Raman观测

碳酸脱水酶去卷曲构象的ＦＴ┐Ｒａｍａｎ观测左晨周群童宇峰郁鉴源（清华大学化学系北京１０００８４）ＦＴ┐ＲａｍａｎＳｐｅｃｔｒｏｓｃｏｐｉｃＳｔｕｄｙｏｎｔｈｅＣｏｎｆｏｒｍａｔｉｏｎｏｆＵｎｆｏｌｄｅｄＣａｒｂｏｎｉｃＡｎｈｙｄｒａｓｅＺｕｏＣｈｅｎ...     

海藻酸钠溶液溶胶—凝胶相转变过程的光谱学研究

以粘度法和＾１３Ｃ－ＮＭＲ、ＵＶ、Ｒａｍａｎ光谱学方法研究了海藻酸钠溶液胶－凝胶相结转变过程，结合体系的光谱学特征，分析了体系相转变过程中海藻酸单体官能基与二价铜离子间的结合情形、分子链的构型变化以及与它紧密相关溶剂行为，进一步探讨了天然高分子电南海藻酸钠在重金属离子Ｃｕ＾２＋作用下的凝胶化机理。     

振动光谱法研究γ-球蛋白同银(I)离子的作用

用Ｒａｍａｎ和ＦＴＩＲ光谱法研究了γ－球蛋白同银（Ｉ）离子的相互作用。结果表明，γ－球蛋白表面的氨基酸残基可同银（Ｉ）离子反应，生成２或４配位的物种，其振动光谱在酰胺带区域呈现明显差异。研究了在恒定的加热温度下不同反应时间对振动Ｒａｍａｎ光谱的影响。结果表明，Ｒａｍａｎ光谱强度在１５ｍｉｎ左右有最大值，当时间超过１５ｍｉｎ后，物种中的银离子被还原为单质银     

振动光谱法研究γ—球蛋白同银（Ⅰ）离子的作用

和Ｒａｍａｎ和ＦＴＩＲ光谱法研究了γ－球蛋白同银（Ｉ）离子的相互作用，结果表明，γ－球蛋白表面的氨基酸残基可同银（Ⅰ）离子反应，生成２或４配位的物种。其振动光谱在酰胺带区域呈现明显差异。研究了在恒定的加热温度下不同反应时间对振动Ｒａｍａｎ光谱的影响，结果表明，Ｒａｍａｎ光谱强度在１５ｍｉｎ左右有最大值，当时间超过１５ｍｉｎ后，物种中的银了子被还原为单质银。     

Raman和FT—IR光谱研究乙酰胺和银（Ⅰ）,铜（Ⅱ）离子的作用

用Ｒａｍａｎ和ＩＲ光谱研究乙酰胺和Ａｇ（Ⅰ）－Ｃ（Ⅱ）离子的作用。结果发现，Ａｇ（Ⅰ）和Ｃｕ（Ⅱ）离子可增强对乙酰胺光谱频带的识别能力，原在ＡＡ中被掩盖的某些谱带，由于Ａｇ－Ｃｕ离子的进入而得到了辨认。     

易解石族矿物的Raman光谱和光致发光谱研究

测定并讨论了中国白云鄂博矿区变生及退火晶态易解石族矿物Ｒａｍａｎ光谱和光致发光谱,与退火晶质矿物相比,变生态易解石的Ｒａｍａｎ光谱和光致发光谱的强度降低,谱线宽化弥散,说明在变生过程中,矿物的结构发生畸变,元素分布趋于无序。分析表明,易解石族矿物在５１４．５ｎｍ激光激发下的所有光致发光谱峰均出自Ｎｄ＾３＋的辐射跃迁。     

非均匀等离子体中受激Raman散射非线性行为

鉴于实际中等离子体不均匀性和非周期性边界条件，建立了受激Ｒａｍａｎ散射（ＳＲＳ）和受激Ｂｒｉｌｌｏｕｒｉｎ散射（ＳＢＳ）非线性耦合模型。ＳＢＳ对ＳＲＳ的影响主要表现在两方面：１）Ｌａｎｇｍｕｉｒ波与离子声波的非线性相互作用，２）ＳＢＳ与ＳＲＳ的竞争。本文研究了离子声衰变不稳定性、离子声波对Ｌａｎｇｍｕｉｒ波的非共振散射两种非线性过程在ＳＲＳ发展过程中的作用，给出一维不均匀等离子体中ＳＲＳ发展图象。Ｌａｎｇｍｕｉｒ波向短波转换，从而被强烈阻尼是抑制ＳＲＳ的重要机制。文中给出了ＳＢＳ／ＳＲＳ耦合过程中决定ＳＲ 关键词：     

纳米Ge颗粒镶嵌薄膜的Raman散射光谱研究

研究了镶嵌在ＳｉＯ_２介质中的不同尺寸（４—１６ｎｍ）纳米Ｇｅ颗粒的Ｒａｍａｎ散射谱特征，与大块标准Ｇｅ晶体的散射峰相比，观察到了理论预期的纳米半导体粒子的Ｒａｍａｎ散射峰的宽化和红移现象．采用声子限域模型较好地解释了实验结果．探讨了ＳｉＯ_２介质基体作用于镶嵌Ｇｅ粒子的压应力以及纳米Ｇｅ粒子的表面界面效应对Ｒａｍａｎ散射光谱的峰形、峰位变化所产生的影响 关键词：     

高氯酸锂在有机溶剂中离子溶剂化和离子缔合的红外光谱研究

利用红外光谱技术研究了LiClO4在碳酸丙烯酸,γ－丁内酯和碳酸二乙酯中的离子缔合和离子溶剂化。溶剂分子谱带的变化证明,锂离子与溶剂分子的相互作用主要是通过羰基氧原子进行的,醚氧也可能参与了相互作用,高氯酸锂的v1和v4谱带变化则证明了溶液中离子对的存在,而离子对的种类与溶剂分子的特性有关。     

Evaluation of ionic conductivity for Mg–Al layered double hydroxide intercalated with inorganic anions

This study demonstrates that humidity, temperature, and the interlayer anions influence ionic conductivities of Mg–Al layered double hydroxides (LDHs) intercalated with inorganic anions. Results show that Mg–Al LDH intercalated with Br^? exhibited the highest ionic conductivity among Mg–Al LDHs intercalated with CO₃^2?, Cl^?, Br^?, NO₃^? and SO₄^2?. Its ionic conductivity was 1.1 × 10^? 2 S cm^? 1 at 80 °C under 80% relative humidity. The electromotive force for the hydroxide ion concentration cell using Mg?Al CO₃^2? LDH showed the same behavior with that using an anion exchange membrane, indicating that Mg–Al CO₃^2? LDH can be a hydroxide ion conductor.     

Estimation of the solubility product of hydrocalumite–hydroxide,a layered double hydroxide with the formula of [Ca2Al(OH)6]OH·nH2O

From aqueous NaOH/Ca(OH)₂/NaAl(OH)₄ mixtures, after allowing short reaction times we observed the precipitation of Ca(OH)₂(s) at lower, and a mixture of Ca(OH)₂(s) and a layered double hydroxide, hydrocalumite (HC) at higher aluminate concentrations. From the maximum aluminate concentration, at which the equilibrium solid phase is still portlandite (i.e., further increase in the aluminate concentration results in HC appearing in the precipitate beside the portlandite), the concentration based solubility products of two polymorphs of HC with the formula of [Ca₂Al(OH)₆]OH·nH₂O (differing in n) has been estimated and was found to be log L_HC=−11.4 at 25 °C and −12.1 at 75 °C, respectively (where L_HC=[Ca²⁺]²[Al(OH)₄⁻][OH⁻]³) and at constant ionic strength (I=1 M NaCl). To the best of our knowledge, this is the first published estimate for the solubility product of hydrocalumite. Additionally, from the composition obtained for NaOH/Ca(OH)₂/NaAl(OH)₄ mother liquors in equilibrium with Ca(OH)₂(s), attempts were made to extract the formation constant of the ion pair CaAl(OH)₄⁺. It was found, that the effects caused by the supposed formation of this solution species are too small to be reliably determined, which allowed an upper estimate for its formation constant, K, to be suggested in the temperature range of 25–75 °C (K<200 and 40 M⁻¹ at 25 and 75 °C, respectively).     

Tris(hydroxymethyl)phosphine,P(CH2OH)3 – A convenient and effective new reagent for the fixation of protein samples for SEM imaging

Tris(hydroxymethyl)phosphine [P(CH₂OH)₃, THP] is demonstrated to be an alternative fixative to glutaraldehyde for preparation of proteinaceous specimens for SEM analysis. THP is easily prepared from commercially-available [P(CH₂OH)₄]Cl, and unlike many other alkylphosphines, is reasonably air-stable [>7 days at pH 7–8]. Experiments carried out with chicken breast muscle, cross-sectioned perpendicular to the muscle fibres and imaged using SEM, indicate that THP effectively fixes the muscle structure with minimal discolouration of the sample.     

Sonochemical synthesis and characterization of Co3O4 nanocrystals in the presence of the ionic liquid [EMIM][BF4]

For the first time, a sonochemical process has been used to synthesis cobalt oxide Co₃O₄ nanoflowers and nanorods morphology in the presence of the ionic liquid 1-Ethyl-3-methylimidazolium tetrafluoroborate [EMIM][BF₄] as reaction media and morphology template. Different sonication time periods and different molar ratios of the ionic liquid (IL) were used to investigate their effects on the structural, optical, chemical and magnetic properties of the produced Co₃O₄ nanoparticles. During synthesis process brown powder contains cobalt hydroxide Co(OH)₂ and cobalt oxyhydroxide (Cobalt hydroxide oxide) CoO(OH) was formed, after calcination in air for 4 h at 400 °C a black powder of Co₃O₄ nanoparticles was produced. The produced Co₃O₄ nanoparticles properties were characterized by X-ray diffraction (XRD), Field Emission Scanning Electron Microscopy (FE-SEM), transmission electron microscopy (TEM), FTIR spectroscopy, UV–vis spectroscopy, and Vibrating Sample Magnetometer (VSM). To explain the formation mechanism of Co₃O₄ NPs some investigations were carried on the brown powder before calcination.     

Quadrupole Splitting Distribution of Fe2+ in Synthetic Trioctahedral Micas

Hyperfine Interactions - About 80 different synthetic trioctahedral micas {K}[Fe2+ 3?x Me x ]〈Si,Al,Fe〉4O10(OH)2 with Me = Ni2+, Mg2+, Co2+, Al3+ and Fe3+ have been synthesized...     

Surface structures of equimolar mixtures of imidazolium-based ionic liquids using high-resolution Rutherford backscattering spectroscopy

Surface structures of equimolar mixtures of imidazolium-based ionic liquids (ILs) having a common cation (1-butyl-3-methylimidazolium ([C₄MIM]) or 1-hexyl-3-methylimidazolium ([C₆MIM])) and different anions (bis(trifluoromethanesulfonyl)imide ([TFSI]), hexafluorophosphate ([PF₆]) or chlorine) are studied using high-resolution Rutherford backscattering spectroscopy (HRBS). Both cations and anions have the same preferential orientations at the surface as in the pure ILs. In the mixture, the larger anion is located shallower than the smaller anion. The [TFSI] anion is slightly enriched at the surface relative to [PF₆] with coverage of ~ 60% for the equimolar mixtures of [C₄₍₆₎MIM] [TFSI] and [C₄₍₆₎MIM] [PF₆]. No surface segregation is observed for [C₆MIM] [TFSI]_0.5[Cl]_0.5 and [C₆MIM] [PF₆]_0.5[Cl]_0.5. These results are different from the recent TOF-SIMS measurement where very strong surface segregation of [TFSI] was concluded for the mixture of [C₄MIM] [TFSI] and [C₄MIM] [PF₆].     

Study on the three-photon properties of a triphenylamine derivative with three conjugated branches

Three-photon pumped frequency-upconversion fluorescence and nonlinear transmission properties of tris-[4-(2-{4-[5-(4-tert-butyl-phenyl)-[1,3,4]oxadiazol-2-yl]-phenyl}-vinyl)-phenyl]-amine (TPAD3) are studied using a Ti:Sapphire oscillator–amplifier system associated with an optical-parametric amplifier, which could specifically provide ～80 fs duration and 1175–1300 nm laser pulses for three-photon excitation. The dye shows very efficient three-photon pumped frequency-upconversion fluorescence and three-photon absorption at wavelengths from 1175 nm to 1300 nm. In our study, the beam intensity distribution is also taken into account. For the first time we give the analytical solution to nonlinear transmission of a three-photon absorption process when the incident beam has a Gaussian transverse spatial profile.     

Structural,optical and electrical properties of europium picrate tetraethylene glycol complex as emissive material for OLED

A new europium complex [Eu(Pic)₂(H₂O)(EO4)](Pic)·0.75H₂O was synthesized and used as the emission material for the single layer device structure of ITO/EO4–Eu–Pic/Al, using a spin-coating technique. Study on the optical properties of the [Eu(Pic)₂(H₂O)(EO4)](Pic)·0.75H₂O complex where EO4=tetraethylene glycol and Pic=picrate anion, had to be undertaken before being applicable to the study of an organic light emitting diode (OLED). The electrical property of an OLED using current–voltage (I–V) measurement was also studied. In complex, the Eu(III) ion was coordinated with the EO4 ligand as a pentadentate mode, one water molecule, and with two Pic anions as bidentate and monodentate modes, forming a nine-coordination number. The photoluminescence (PL) spectra of the crystalline complex in the solid state and its thin film showed a hypersensitive peak at 613.5–614.9 nm that assigned to the ⁵D₀→⁷F₂ transition. A narrow band emission from the thin film EO4–Eu–Pic was obtained. The typical semiconductor I–V curve of device ITO/EO4–Eu–Pic/Al showed the threshold and turn on voltages at 1.08 and 4.6 V, respectively. The energy transfer process from the ligand to the Eu(III) ion was discussed by investigating the excitation and PL characteristics. Effect of the picrate anion on the device performance was also studied.     

水溶性BSA-羟基磷灰石-碳酸钙复合物的形成机理

本文以傅里叶变换红外光谱为手段,对不同反应摩经的牛血清蛋白（ＢＳＡ）、羟基磷灰石、碳酸钙固体在水溶液中反应后的滤液进行了研究,谱带峰位和强度的变化表明,ＢＳＡ与羟基磷灰石、碳酸钙以多种形式的络合配位及氢键等结合,使难溶钙盐的溶解度增加,形成三元水溶性复合物,其复合物的组成随反应摩尔比的改变而有差异,具有化学计量的性质。     

Oxidation of silicon surface with atomic oxygen radical anions

The surface oxidation of silicon （Si） wafers by atomic oxygen radical anions （O- anions） and the preparation of metal-oxide-semiconductor （MOS） capacitors on the O-oxidized Si substrates have been examined for the first time. The O- anions are generated from a recently developed O- storage-emission material of [Ca24Al2sO64]^4＋·4O^- （Cl2A7-O^- for short）. After it has been irradiated by an O- anion bean： （0.5 μA/cm^2） at 300℃ for 1-10 hours, the Si wafer achieves an oxide layer with a thickness ranging from 8 to 32 nm. X-ray photoelectron spectroscopy （XPS） results reveal that the oxide layer is of a mixture of SiO2, Si2 O3, and Si2O distributed in different oxidation depths. The features of the MOS capacitor of 〈Al electrode/SiOx/Si〉 are investigated by measuring capacitance-voltage （C - V） and current-voltage （I - V） curves. The oxide charge density is about 6.0 × 10^1 cm^-2 derived from the （C - V curves. The leakage current density is in the order of 10^-6 A/cm^2 below 4 MV/cm, obtained from the I - V curves. The O- anions formed by present method would have potential applications to the oxidation and the surface-modification of materials together with the preparation of semiconductor devices.