复合近红外光谱法在牛奶测定中的应用

研究了用于快速测定牛奶主要成分含量的近红外透射光谱法和漫反射光谱法,分析了两种方法在实际测量中的差异,并提出将两种方法结合形成复合光谱法用于牛奶成分含量的检测。结果表明:复合光谱法的应用有效地提高了多变量回归分析中牛奶成分含量的预测精度。     

光谱透射比标准物质的研究

研制了紫外、可见、近红外光谱区通用光谱透射比较标准物质。以高纯熔融石英为基片材料，镍铬合金的镀膜材料，采用双光楔对称光胶结构以消除同色杂散光的影响，对镀膜进行光胶处理以保证膜层的强度、稳定性及光学中性，采用高精度分光光度测量装置作为定值手段的以保证准确的定值，设计定位保护架以消除多次反射误差。该光度标准适用的光谱范围的200-2600nm，光谱透射比定值不确定度为0.5%。     

现场光谱电化学研究的新进展

电化学以两个凝聚相的荷电界面为其主要研究对象．它广泛地应用于能源、材料等重要科学领域，并对生命科学的发展发挥着重要作用［1，2］．为了从分子水平上深化对电化学界面的认识，自七十年代中至八十年代初采用了紫外可见反射、拉曼和红外光谱技术对电化学体系进行现场（in-situ，又称原位）研究，开创了光谱电化学新领域[3,4]．光谱电化学在／＼十年代发展迅速，推动电化学研究由宏观进入微观、由统计平均深入至分子水平【‘一刀．近年来，随着各种光谱仪器性能的提高以及非线性光谱等新技术的发展，现场光谱电化学研究不断拓宽新领域，…     

高分辨率电感耦合等离子体光谱谱线数据库 I.镧、铈、镨、钕、钐

讨论了高分辨率光谱实验的光谱仪参数。在带宽3pm条件下摄取了稀土元素La、Ce、Pr、Nd、Sm的高分辨率ICP光谱,鉴别了240～450mm波长范围内的谱线,估测了强度.观察到一些谱线的复杂物理轮郭。     

多用途薄层光谱电化学池的设计和表征

设计并组装了一种简易薄层光谱电化学池.该池具有结构简单、操作方便、对工作电极无透光要求,且能适用于多种现场光谱电化学研究的特点.用该池记录了邻联甲苯胺高氯酸醋酸组成的氧化还原体系的荧光光谱电化学和紫外可见光谱电化学响应,并用吡啶氯化钾体系进行了喇曼光谱电化学表征.     

电化学谱学表征方法的应用与发展

经历两个多世纪的发展,电化学表征方法的理论和实验研究不断完善,在表界面精细结构表征、电化学反应机理研究等方面起到重要作用。电化学谱学表征技术的出现,填补了传统电化学表征方法在分子水平上鉴定电化学反应活性位点及中间物种的空白。本文总结了近年来红外光谱(IR)、表面增强拉曼光谱(SERS)及和频振动光谱(SFG)三种经典分子振动光谱电化学表征技术的研究进展。首先介绍了三种光谱的基本原理和电化学联用电解池的设计,然后从基础电化学理论出发,介绍其在模型单晶体系及界面水机理研究中的应用,进一步重点介绍了其在锂离子电池和燃料电池领域的相关研究进展,最后展望了电化学谱学表征技术的未来发展方向。     

微机化紫外可见区现场光谱电化学联用测量系统的研制

本文报道了由微机控制的紫外可见区现场(in situ)光谱电化学联用测量系统的硬件和软件设计。该系统可以测量电化学调制反射光谱,光电流谱和光电容谱,并可实现同一实验体系的同时联合测量,这些功能均由计算机软件完成。该系统已应用于金属、半导体、半导电氧化膜电极/溶液界面行为的研究,得到了一些新的实验结果。     

鸟嘌呤,鸟苷及其甲基化衍生物的近红外傅里叶变换表面增强拉慢光谱

本文给出了采用表面增强傅里叶变换拉慢光谱法测定的鸟嘌呤、鸟苷及其甲基化衍生物的拉曼散射，实验结果表明，采用了近红外波长的平拉曼散射及傅里叶变换技术成功地获得鸟嘌呤、鸟苷及其甲基化衍生物的水溶液在较低浓度下（０．１－０．０１ｍｇ／Ｌ）不受荧光干扰的拉曼光谱图，其频率与相对强度分布表明，水溶液状态下吸附在Ａｇ膜上的鸟嘌呤（苷）及其衍生物结构中的有关振动谱带ｒ（Ｃ＝Ｏ）、ＮＨ２和杂环上的Ｎ获得显著增强。     

叠氮化钠与烟草多酚氧化酶相互作用的光谱学研究

N₃^- is a kind of ligand with very strong power for coordination, and is able to bind with many kinds of metal ions or metalloproteins. The metal ions in metalloproteins usually locate at the active site of them, and the combination of other chemical compound(s) to them will cause great influence on the structure and function of them. In addition, the combination can also provide information of the structure of the active site of the enzymes, and that of the higher-order structure of the enzyme. In this paper, we studied the interaction between N₃^- and PPOⅡ from Nicotina Tobacco by the determination of changes in enzymatic activity, UV-Vis, fluorescence spectra and FT-IR. The results showed that N₃^- can activate PPOⅡ with a near linear increase in enzymatic activity to the concentration of N₃^- when the [N₃^-]/[PPOⅡ](molar/molar) is less than or equal to 1.0, and that the enzymatic activity begins to decrease from 1.0 to 4.0; N₃^- didn’t coordinate directly with Cu²⁺ in the active site, but may interact with the side chain groups with positive charges, and further resulted in the increase in α-helix and the slightly decrease in β-turn, random coil and extended chain; the Cu²⁺ may locate deeply in the inner part of PPOⅡ, and coordinates strongly with nitrogen atoms in imidazole of histidine; N₃^- can quench the fluorescence of PPOⅡ, and make the microenvironments of Trp residues more polar after the interaction between N₃^- PPOⅡ.     

LiNbO3：Mg,Er晶体的光谱性质

铌酸锂(LiNbO_3)晶体是优良的电光和非线性光学材料。自从该晶体的光折变损伤被克服以来,MgO与稀土离子双掺LiNbO_3晶体的研究开始活跃起来,并首先在LiNbO_3:Mg,Nd中获得1.093μm和自倍频0.546μm激光输出。Er~(3+)是重要的激活离子,可在十几个通道实现激光输出。作者曾在文献[2]和[3]中首次报道了LiNbO_3,Er晶体生长特性及表面分析的研究结果,本文将介绍该晶体的光谱特性,并讨论LiNbO_3:Mg,Er晶体作为激光材料的可能性。     

Eu（DBM）3纳米微晶的低频喇曼光谱

低频喇曼（LFR）光谱技术广泛应用于无序体系的结构性质研究，它能提供有关微粒的非弹性振动、量子尺寸效应以及分形体的光散射性质等方面的信息［‘一句.尤其是通过LFR光谱的研究，可以确定分形体振动（频率为叫激发的光谱线数已用于描述分形结构的局域振动量子一分形子的态密度：N（川。0‘’‘，又称之为分形干线教，是联系“几何结构”与“动力学行为”的重要参数.对它进行深入而广泛地研究，将有可能为更深入地认识无序材料的物理、化学性质带来重大的突破，因而引起人们的极大兴趣.其研究工作主要集中于非晶态的硅溶胶和玻璃体系［…     

C60离子束撞击固体表面的坍塌沉积(I)共焦显微拉曼光谱研究

Raman spectroscopy was applied to characterize the species deposited from the mass-selected C60 ion beam which was accelerated to 900 eV. The substrates for the deposition were (0001) surface of highly oriented pyrolitic graphite and (111) surface of gold crystal. The species do not exhibit the Raman scattering features of buckminsterfullerene, but displays peaks at 1585 and 1332 cm-1 instead. The former peak is the chararteristic Ranan peak of hexagonal graphite, and the latter can be attributed to the amorphous carbon in sp3 hybridization. The result reveals that C60 was collapsed to form a new phase when it collides on the solid surface.     

Intramolecular hydrogen bonding. Spectroscopic and theoretical studies of vibrational transitions in dibenzoylmethane enol

The vibrational structure of the title compound (DBM) was investigated by FTIR spectroscopy in liquid solutions, by FTIR linear dichroism (LD) measurements, and by Raman spectroscopy. The results were supported by the application of theoretical model calculations and analyzed with particular attention to the possible origin of the broad, very strong, and irregularly shaped absorbance band observed in the 1700–1400 cm⁻¹ region. The orientation factors derived from the observed LD data indicate that rotational dynamics of the phenyl groups do not contribute significantly to the broadening of the band. The position of the two sharp Evans transmission windows near 1580 and 1500 cm⁻¹ is unaffected by deuteration of the reactive protons in DBM. The transmissions coincide with prominent peaks in the Raman spectrum and can be assigned to combinations of phenylic modes (9a, 18a) with low IR intensity, but large Raman scattering activity.     

ZrO2表面B2O3的分散及其作用状态

用XPS、FT IR和FT Raman等技术研究了ZrO2表面B2O3的分散及其作用状态,测定了B2O3在ZrO2表面的分散阈值.结果表明：B2O3在ZrO2表面可以三配位BO3和四配位BO4结构单元存在;载体ZrO2的预焙烧温度和硼含量对B2O3的分散及作用状态有较大影响,并改变BO3与BO4结构单元之间的比例.实验测得B2O3在ZrO2载体上的单层分散阈值为0.05 gB2O3/gZrO2（或B2O3的质量分数w=4.76％）,处在此单层中的硼原子以BO4为结构单元直接与ZrO2表面相作用.只有当B2O3的负载量超过此（单层）分散阈值时, BO3结构单元才会形成.     

Raman spectroscopic analysis of GeS2-Ga2S3-PbI2 chalcohalide glasses

The structures of pseudo-binary GeS2-PbI2, Ga2S3(GaS)-PbI2 and pseudo-ternary GeS2-Ga2S3-PbI2 chalcohalide systems were investigated by Raman scattering spectroscopy. By evolving the vibrational bands as a function of PbI2 content, it was verified that the effect of addition of PbI2 to the glass network is threefold, namely: (i) the conversion of GeS4 tetrahedra to GeS3I and GeS2I2 structural units, (ii) the destruction of ethane-like S3Ga(Ge)-(Ge)GaS3 structural units and formation of GaS3I and GeS3I ones and (iii) formation of short S-S chains and [PbIn] structural units when the concentration of PbI2 is high.     

Ce3+,Tb3+,Eu3+共掺杂Sr2MgSi2O7体系的白色发光和能量传递机理

通过正交试验,采用高温固相法制备了Sr2-x-y-zMgSi2O7∶xCe3+,yTb3+,zEu3+系列样品.使用X射线衍射仪和荧光光谱仪表征了样品的物相和发光性质,并讨论了Ce3+-Tb3+-Eu3+共掺杂Sr2MgSi2O7体系中的能量传递过程.实验结果表明,在327 nm波长激发下,所合成荧光粉的发射峰主要位于387 nm(蓝紫)、542nm(绿)和611 nm(红)处;分别以387,542和611 nm为监控波长,所得激发光谱显示荧光粉在327 nm处有最好的激发.在327 nm光激发下,系列样品发光进入白光区.最优化的荧光粉为Sr1.91MgSi2O7∶0.01Ce3+,0.05Tb3+,0.03Eu3+,其色坐标为(0.337,0.313),是一种潜在的发光二极管(LED)用白色荧光粉.     

CaSiO3从熔体到玻璃的结构和拉曼光谱性质研究

采用分子动力学模拟以及一种计算拉曼谱的新方法研究了CaSiO₃从高温熔体淬火到室温玻璃态的过程中微结构性质和拉曼谱的变化。在结构变化中，主要是键长随温度的降低而缩短，并且Si-O_b键长的下降幅度明显比Si-O_nb的下降幅度大，另外Si-O_b和Si-O_nb两种键的物质的量分数的变化说明温度的降低使体系的无序度降低。随着温度的降低，偏拉曼谱中表征5种Q_i的强特征峰的频率都呈上升趋势，而且基本与温度呈一个直线关系。计算结果还证实，温度对拉曼散射系数没有影响。得到的拉曼散射系数的两个比值分别为：S₃/S₂=0.3987和S₂/S₁=0.4801，与实验值吻合得非常好。     

Eu(DBM)3超微粒子的光谱特性

The colloids of Eu(DBM)3 and ultrafine particles Eu(DBM)3 were perpared. The particle sizes determined by X-ray and by TEM measurements were in 7-30nm range. Their UV absorption and fluorescence spectra were compared with each other and with those of the solid sample. It was shown that the 5D1→7 F1,2 transition was observed in the colloids of Eu(DBM)3 at room temperature. The increase of the excited-state S1 and T1 energy, the peak positions of UV absorption shifted to shorter wavelength, the changes of the absoprtion coefficient with decreasing size were observed.     

白色荧光粉NaGd（MoO4）2:Dy3+,Eu3+的水热合成及发光性能

采用谷氨酸辅助水热法合成了八面体形NaGd(MoO4)2:Dy3+,Eu3+白色荧光粉.X射线衍射结果表明,合成的样品为四方晶系的NaGd(MoO4)2纯相.扫描电子显微镜照片显示所制备的粒子为八面体形,各边长约为2μm.荧光光谱结果表明,在NaGd(MoO4)2:4%Dy3+,yEu3+(y=0,0.5%,0.6%,0.7%,0.8%,0.9%,1.0%)样品中,随着Eu3+掺入量的增加,Dy3+的发射峰逐渐减弱,而Eu3+的发射峰逐渐增强,说明Dy3+-Eu3+之间存在能量传递.通过色坐标图可知,当Eu3+掺杂量y=0.9%时,荧光粉的色坐标(0.338,0.281)与标准的白光色坐标(0.33,0.33)接近,表明NaGd(MoO4)2:4%Dy3+,0.9%Eu3+是很好的近紫外光激发下的白色荧光粉.     

一氧化氮在Cu_3Pt(111)表面的吸附行为

运用密度泛函理论中广义梯度近似(GGA)的PW91方法,结合周期性平板模型,探讨了NO分子在Cu3Pt(111)表面上不同吸附位的吸附行为.结果表明:NO分子以N端朝下方式吸附在top-Pt以及hcp1和fcc2位(分别为表面Cu2Pt和Cu3簇)的吸附模式最稳定,吸附能分别为101.8、124.5和118.1kJ·mol-1.对于hcp1和fcc2位的吸附,NO中的N原子分别与底物的Cu2Pt和Cu3簇成键.吸附前后的电荷布居、态密度和振动频率的分析结果表明,净电子从底物合金表面转移到NO,N—O键伸长,频率发生红移.合金Cu3Pt和纯贵金属Pt对NO的吸附性质相似.