水溶性维生素核磁共振定量分析的研究

药物核磁共振定量分析法,操作简便,样品用量少,定性鉴定和定量分析同步完成,无须被测物的标准对照品,只须一般内标即可完成定量分析,分析速度和精密度可以达到或接近HPLC法. 作为药物的水溶性维生素,中国药典中还没有核磁共振定量分析方法. 实验数据表明,用核磁共振定量分析法与中国药典中提供的水溶性维生素分析法的分析结果十分吻合,可以达到药品市场监管的要求.     

Airborne Nanostructured Particles and Occupational Health

Nanotechnology is leading to the development in many field, of new materials and devices in many fields that demonstrate nanostructure-dependent properties. However, concern has been expressed that these same properties may present unique challenges to addressing potential health impact. Airborne particles associated with engineered nanomaterials are of particular concern, as they can readily enter the body through inhalation. Research into the potential occupational health risks associated with inhaling engineered nanostructured particles is just beginning. However, there is a large body of data on occupational and environmental aerosols, which is applicable to developing an initial assessment of potential risk and risk reduction strategies. Epidemiological and pathological studies of occupational and environmental exposures to airborne particles and fibers provide information on the aerosol-related lung diseases and conditions that have been observed in humans. Toxicological studies provide information on the specific disease mechanisms, dose–response relationships, and the particle characteristics that influence toxicity, including the size, surface area, chemistry or reactivity, solubility, and shape. Potential health risk will depend on the magnitude and nature of exposures to airborne nanostructured particles, and on the release, dispersion, transformation and control of materials in the workplace. Aerosol control methods have not been well-characterized for nanometer diameter particles, although theory and limited experimental data indicate that conventional ventilation, engineering control and filtration approaches should be applicable in many situations. Current information supports the development of preliminary guiding principles on working with engineered nanomaterials. However critical research questions remain to be answered before the potential health risk of airborne nanostructured particles in the workplace can be fully addressed. Disclaimer The findings and conclusions in this report are those of the authors and do not necessarily represent the views of the National Institute for Occupational Safety and Health     

Characterization of Airborne Particles and Droplets:

Water sprays have been commonly used to suppress airborne dust. Water is doped with surface‐active agents to enhance the dust capture efficiency through a reduction of surface tension. Nevertheless, dust collection efficiencies have been less than satisfactory historically.     

水溶性沥青分子结构的光谱解析

水溶性沥青是煤焦油沥青经酸氧化改质得到的水溶物含量大于70%的改性沥青,不仅兼有普通沥青的多环芳烃结构,同时表面结构中引入了大量含氧、氮、硫等极性官能团,可在水相中制备复合型炭材料。应用荧光、红外、紫外光谱及核磁共振技术并结合Yen-Mullins模型解析了混酸法制备的水溶性沥青的分子结构。结果表明：与中温煤沥青相比,主要杂原子N,O和S质量分数分别由1.06%,11.64%,0.79%增加到6.78%,29.59%,2.41%;O含量的显著增加,增强了沥青的亲水性。红外光谱体现了水溶性沥青的杂原子N,O和S以Ar-NO₂,Ar-OH,Ar-SO₃H和CO等形式存在;通过荧光发射光谱特征峰与Yen-Mullins模型对比,得出水溶性沥青的芳香结构主要是由3种稠环的“岛屿结构”芳香片段组成;1H-NMR和13C-NMR分析表明,水溶性沥青分子芳环侧链被氧化成仅含有1个C且链接不同官能团的脂肪碎片,该碎片与“岛屿结构”作为主要部分构成水溶性沥青分子的稳定结构。由此看出,元素分析结合红外光谱可从本质上解释水溶性沥青易溶于碱性水溶液的原因,荧光谱图与Yen-Mullins模型结合可从微观上解释水溶性沥青的主要结构,为判定不同性质的沥青提供一种方法。     

Alignment of Anisotropic Particles by Magnetic Field as Seen by NMR

We applied ¹³C and ²⁰⁵Tl NMR for studying alignment of particles of graphene and high temperature superconductor (Tl_0.5Pb_0.5)(Ba_0.2Sr_0.8)₂Ca₂Cu₃O_y caused by magnetic field. These compounds have layered structure and reveal anisotropic magnetic susceptibility. We found that the field of 8 T causes minor alignment of powder graphene and somewhat better alignment of fluffy graphene particles. Herewith the effect of alignment is well pronounced in ²⁰⁵Tl spectra of the superconducting particles fixed in epoxy in the field of 8 T. This effect is reflected in the ²⁰⁵Tl line shape measured in a magnetic field of 1.17 T and becomes much more pronounced in measurements made in high magnetic field of 8 T. Spectra simulations allow determining the degree of the particles’ alignment.     

卡泊三醇的核磁共振谱解析

利用核磁共振氢谱（¹H NMR）、碳谱（¹³C NMR）、同核位移相关谱（¹H-¹H COSY）、异核单量子相干谱（HSQC）和异核多键相关谱（HMBC）等多种核磁研究方法对抗银屑病药物卡泊三醇的¹H、¹³C信号进行完全归属.     

Simulation of Fission Product Release from Microfuel Particles Taking into Account the Effects of Trapped Fraction and Concentration Jumps at the Interfaces

A modification of the FP Kinetics code [1] has been performed to calculate the fission product release from HTGR microfuel particles, allowing for chemical binding, limited solubility effects, and component concentration jumps at the interfaces of the coating layers. A comparison is made of the release curves of Cs from microfuel particles calculated using the FP Kinetics and PARFUME codes [2]. It is shown that taking into account the concentration jumps at the interfaces of the silicon carbide layer makes it possible to give a noncontradictory explanation of the experimental data obtained for Cs release in post-reactor thermal testing. The need for performing experiments to determine the limits of solubility in coating materials is noted.

     

基于衰减全反射-傅里叶变换红外光谱技术的气溶胶中水溶性无机离子定量分析方法研究

利用衰减全反射-傅里叶变换红外(ATR-FTIR)光谱技术探讨了气溶胶颗粒物中SO2-₄,NO-₃,NH+₄三种水溶性无机离子的快速无损测量方法。利用IC法测量三种无机离子含量的对照值,结合偏最小二乘(PLS)法建立了三种无机离子的定量分析模型,并对模型进行了评价;利用马氏距离判别法对异常值进行了判别与剔除,并探讨了不同光谱预处理方法和不同光谱范围对建模结果的影响,确定了最佳建模参数。结果表明剔除异常值之后经二阶微分处理的模型预测性能较好,SO2-₄在1 220～900 cm-1光谱范围内预测性能较好,NO-₃在1 521～900 cm-1光谱范围内预测性能较好,NH+₄在1 521～1 220 cm-1光谱范围内预测性能较好,预测均方根误差分别为1.736 7,1.023 9和1.482 3。所建立的模型为实现对大批量气溶胶样品中三种无机离子的实时快速定量分析建立了基础。     

Spectral Analysis and Determination of Palladium II Based on the Environment-Friendly and Water-Soluble Polymer

The environment-friendly and water-soluble polymer was prepared via ring-opening reaction between polyvinyl alcohol (PVA) and 3-epoxypropoxy fluorescein (EPF). Based on the quenching of fluorescence signals of PVA–EPF in the 520 nm wavelength and relative quenched intensity is good linear with the concentration of palladium II. A simple, rapid, sensitive, and specific detection method for palladium II is proposed. In comparison with traditionary methods, the present method is environment-friendly, stable, easy to operation, more water-soluble, and cheaper. The results suggested that PVA–EPF may offer potential as a reusable polymer sensor for palladium II ion in aqueous solution.     

傅里叶变换红外光谱对水溶性气溶胶复折射率的测量分析方法研究

当前大气气溶胶的成分比较复杂,其水溶性离子成分影响着大气质量,并且对人类健康不利。因此,对水溶性离子成分进行快速可靠的检测是环境科学领域中的一项重要研究工作。以SO24-为例,研究采用傅里叶变换红外光谱(FTIR)技术,对水溶性气溶胶离子的消光系数进行测量,并通过理论分析计算得到其复折射率N的过程。通过测量大气气溶胶水溶性SO24-离子的质量消光截面k和消光系数α,再根据消光系数α来计算复折射率N的虚部ni,使用KK(Kramers-Kronig)关系,来计算复折射率N的实部nr,并对实验结果进行了分析和讨论。     

Fraction of boroxol rings in vitreous boron oxide from a first-principles analysis of Raman and NMR spectra

We determine the fraction f of B atoms belonging to boroxol rings in vitreous boron oxide through a first-principles analysis. After generating a model structure of vitreous B2O3 by first-principles molecular dynamics, we address a large set of properties, including the neutron structure factor, the neutron density of vibrational states, the infrared spectra, the Raman spectra, and the 11B NMR spectra, and find overall good agreement with corresponding experimental data. From the analysis of Raman and 11B NMR spectra, we yield consistently for both probes a fraction f of approximately 0.75. This result indicates that the structure of vitreous boron oxide is largely dominated by boroxol rings.     

银杏黄酮的NMR指纹图谱分析

通过 GBE水解后的 1H- NMR,13 C- NMR,DEPT及 1H- 1H COSY,HMQC和 HMBC谱的综合分析 ,确定了槲皮素、山萘酚、异鼠李素这三种主要苷元的信号归属和质量百分含量 ;为银杏黄酮混合物提供了一种有效的指纹图谱及定量分析的方法。     

NMR Spectrometric Analysis of Antazoline

An analytical method is described for the analysis of antazoline [2-(N-benzylanilinomethyl) imidazoline] using pmr. The procedure provides good quantitative results together with a very specific mean for identification of antazoline     

原子吸收光谱法测定霍香花粉中微量元素的含量

采用原子吸收光谱法对霍香花粉的Fe、Cu、Zn、Mn4种元素的含量进行了分析测定。该方法的加标回收率为93.40%—112.00%,RSD值小于2.00%,具有良好的准确度和精密度。研究结果表明：霍香花粉中Fe,Cu,Zn,Mn含量丰富。     

机载星体跟踪器的随机振动与疲劳分析

星体跟踪器是机载天文导航设备的重要组成部分,随机振动是其结构失效的重要因素。采用有限元分析软件Ansys workbench对某机载星体跟踪器进行了随机振动分析,获得了1σ响应值与随机响应谱。根据分析结果进行了随机疲劳计算,得到了疲劳寿命使用系数。该分析方法同样适用于其他光电设备的随机振动与疲劳分析,对光电设备的结构设计有一定的指导作用。     

机载激光雷达风切变探测性能分析

介绍了用于风切变测量的激光雷达外差探测系统，阐述了其工作原理，根据CO2雷达系统与Ho：YAG雷达系统相关参数进行信噪比模拟和风速误差对比，模拟结果表明波长为2．1μm的Ho：YAG雷达和波长为10．6μm CO2雷达都适合机载低空风切变探测。通过对比表明Ho：YAG雷达的性能更为优良，误差更小，探测距离更远。     

几种含氮化合物的核磁共振测试

结合曲氨南（Aztreonam）、奥美拉唑（Omeprazole）与一种席夫碱对含氮化合物在核磁共振（NMR）测试中的某些特性进行了研究. 结果表明,¹⁴N四偶极矩、分子间氢键以及分子间质子转移导致的异构,是影响含氮化合物核磁特性的主要因素. 这些因素虽然在NMR的实验设计与谱图分析方面是无法避免的,但却能为结构解析以及其他化学研究方面提供一定的有趣的信息.     

盐酸马尼地平的核磁共振数据解析

盐酸马尼地平是第三代合成降压新药．本文利用一维、二维核磁共振（NMR）技术,包括¹H NMR、¹³C NMR DEPT-135、¹H-¹H NOESY、¹H-¹H COSY、¹H-¹³C HSQC和¹H-¹³C HMBC,对其¹H和¹³C NMR信号进行了全归属,进一步确证了其分子结构．同时,对其¹H NMR和¹³C NMR谱中一些异常信号进行了讨论．