用傅里叶变换红外光谱差减技术自动监测大气毒物的软件及应用

本文介绍了大气毒物傅里叶变换红外光谱自动差减定量软件，介绍了方法的原理和软件的结构与功能。该技术能够进行数据库的实时咨询，差减谱位的智能搜索和光谱自动差减定量，实现了大气毒物自动定量分析。运用于实际样品分析，快速准确，优于其它的傅里叶变换红外光谱定量技术。     

人工干预的傅立叶变换红外光谱差减技术在大气毒物分析中应用

采用人工干预的傅立叶变换红外光谱差减技术对混合气体中大气毒物进行定量分析，并对其实验条件进行了详细研究和优化，误差在８％以内。同最小二乘法、因子分析法相比，本法无需知道样品全部定性信息，即可进行定量。     

气体样品傅立叶变换红外光谱定量分析的误差研究

通过分析牧场附近的大气傅立叶变换红外(FT-IR)光谱中NH<,3>的浓度,系统研究了气体样品盯FT-IR光谱定量分析的误差;分析了不同精度要求下的定量方法及其实现.选择63个实测光谱作为分析对象,其中NH<,3>的浓度分布在0～1400 μmol·mol<'-1>·m.定量分析采用3个NH<,3>参考光谱,浓度分别为...     

傅立叶变换红外光谱法在高聚物分析中的进展

本文综述了漫反射傅立叶变换红外光谱法，傅立叶谱换红外光声光谱法，显微傅立叶变换红外光谱法，傅立叶变换红外光谱仪与各种仪器的联用，以及计算机技术等在高聚物分析中的应用。     

天然水体底质中腐植酸的光谱表征

分别用紫外-可见光谱、傅立叶变换红外光谱(FTIR)、三维荧光光谱和荧光等高线谱对提取的腐植酸和商品腐植酸进行了表征，并将分析结果与Aldrich和上海试剂二厂生产的腐植酸进行了比较。结果表明：3种底质腐植酸之间以及同商品腐植酸的紫外-可见光谱、傅立叶变换红外光谱(FTIR)相似，含有相同类型的官能团。对不同腐植酸的三维荧光光谱和荧光等高线谱的分析表明其在结构上存在一定的差异；腐植酸有较明显的荧光光谱特性，可以尝试使用三维荧光光谱技术来揭示其在结构上的差异。     

傅立叶变换红外光谱技术在分析化学领域的应用

傅立叶变换红外光谱(FTIR)技术已经成为当前分析化学领域的一个重要的分析检测手段,在众多方面发挥着显著的作用.系统介绍了近年来傅立叶变换红外光谱技术在结构表征、化合物定性、反应动力学、品质鉴别、临床医学、微生物研究、法庭医学、地质科考、环境检测等方面的应用进展情况.     

应用红外差谱技术测定二元混纺纤维的种类

应用傅立叶变换红外光谱测定六种二元混纺纤维,得到了清晰的红外光谱图,应用计算机差谱技术得到高质量的差谱结果,准确判明了混纺纤维的种类。本方法不需要对混纺纤维进行分离、预处理,制样简单、准确度好、操作简便。     

大气中痕量气体污染物的傅里叶变换红外光谱分析

本文从两种类型的长光程气体红外吸收方法的角度，介绍了傅里叶变换红外光谱在大气痕量气体污染物分析中的应用，并评述了它的现状和发展前景。     

本刊1996总目次

题　　目作　者　页码第15卷　第1期电感耦合器件检测器同时测定多组分荧光物质熊少祥等(1)…………………………………………………同步辐射白光全反射XRF在痕量元素检测的初步研究吴应荣等(6)………………………………………人工干预的傅立叶变换红外光谱差减技术在大气毒物分析中应用许国旺等(12)……………………………一种分析土壤中超痕量气相金的新技术——RIS-TOF谱仪马万云等(17)……………………………………ICP-AES中内标法的应用研究　.用内标法校正基体干扰郑建国等(21)…………………………………在胶束溶液中用5-Br-P…     

红外光谱法测定壳聚糖含量(英文)

采用吡喃环上的次甲基的吸收峰(1 389和2 865cm-1)面积比作为定量参照,建立了一种检测壳聚糖含量的傅立叶变换红外光谱(FT-IR)分析方法,并验证了其适用性.结果表明,所建立的FT-IR分析方法可用于定量测定药物剂型中的壳聚糖含量.     

NMR shielding and a thermodynamic study of the effect of environmental exposure to petrochemical solvent on DPPC,an important component of lung surfactant

The chemical and petrochemical industries are the major air polluters. Millions of workers are exposed to toxic chemicals on the job, and it is becoming more toxic, causing much damage to respiratory system, today. One of the main components of lung alveoli is a surfactant. DPPC (Dipalmitolphosphatidylcholine) is the predominant lipid component in the lung surfactant, which is responsible for lowering surface tension in alveoli. In this article, we used an approximate model and ab initio computations to describe interactions between DPPC and some chemical solvents, such as benzene, toluene, heptane, acetone, chloroform, ether, and ethanol, which cause lung injuries and lead to respiratory distress such as ARDS. The effect of these solvents on the conformation and disordering of the DPPC head group was investigated by calculations at the Hatree-Fock level using the 6–31G basis set with the Onsager continuum solvation, GAIO, and frequency models. The simulation model was confirmed by accurate NMR measurements as concerns conformational energy. Water can be the most suitable solvent for DPPC. Furthermore, this study shows that ethanol has the most destructive effect on the conformation and lipid disorder of the DPPC head group of the lung surfactant in our model. Our finding will be useful for detecting the dysfunction of DPPC in the lung surfactant caused by acute or chronic exposures to air toxics from petrochemical organic solvent emission source and chronic alcohol consumption, which may lead to ARDS. The article is published in the original.     

消除显微红外光谱水汽噪音的方法

测量显微红外光谱时,由于光路暴露在开放流通的空气环境中,水汽的吸收峰常常出现在光谱图中而对样品谱造成干扰。本研究在样品单光束谱收集过程中间,通过适时向测试体系通入干燥的氮气或较潮湿的空气来补偿光路中水汽的量,从而达到样品谱和背景谱测量时水汽的平均含量相等,最终消除水汽吸收峰。本方法用于硬脂酸显微红外光谱的测量,观察到水汽噪音由大到小,直至消失的全过程,结果令人满意。     

Ambient air monitoring with Auto-gas chromatography running in trigger mode

Speciated volatile organic compounds (VOC), either as ozone precursors or air toxics in the air, are commonly monitored by triggered canister method or continuous ozone precursor analyzer (commonly known as Auto-gas chromatography (GC)) method. In the triggered canister method, a canister sample is collected when a total non-methane organic compound (TNMOC) concentration exceeds a pre-determined trigger level. The canister sample is then analyzed in a lab in a later time. In the Auto-GC method, an online GC runs in a “continuous” mode with a sampling and analysis cycle of 1 h. Within the cycle hour, samples are collected only during the first 40 min.A new approach of Auto-GC running in trigger mode is developed in this study. This new approach uses Auto-GC but operates it in a trigger mode similar to the triggered canister sampling method. Compared to the triggered canister sample method, this system provides near real-time speciated VOC data, which are critical for responding to a high VOC concentration episode. Although the canister system generally costs less, its cost advantage may diminish if trigger events are frequent and the monitoring duration is long. Compared to continuous Auto-GC, triggered GC has its niche—it is better for capturing transient plumes with a small footprint. The continuous GC either misses a transient plume if the plume does not arrive at the sampling site during the sampling cycle or flattens the plume concentration peak by dilution with non-plume air sample.Field experience with this system for fenceline VOC monitoring is presented. The sampling and calibration strategy for trigger mode operation is described. The chromatograph retention time drift issues are discussed. The system performance is evaluated, including the method detection limit, precision and accuracy. The trigger mode configuration for VOC fenceline or near source monitoring in this work proved effective for local and transient plume identification.     

FT-IR study of the stabilization reaction of polyacrylonitrile in the production of carbon fibers

The stabilized fibers prepared by heating PAN and a PAN copolymer in air and under reduced pressure have been examined by FT-IR spectroscopy in order to determine their chemical structures. Three kinds of reactions, cyclization, dehydrogenation, and oxygen uptake are found to occur almost simultaneously in the stabilization process in air by digital difference spectrum method. The effect of the comonomer is confirmed to accelate the dehydrogenation reaction and also the formation of acridone ring in the thermal stabilization in air by kinetic study.     

Photolysis-assisted, long-path FT-IR detection of air pollutants in the presence of water and carbon dioxide

Seven important air pollutants have been investigated by photolysis-assisted FT-IR spectroscopy. This technique renders invisible the spectra of water and carbon dioxide, which are two of the main concerns in long-path infrared spectroscopy. A cell, equipped with a UV lamp, was used to oxidise the analyte in the air sample and the spectrum recorded was used as a new background for the original sample spectrum. The optimum UV irradiation time and correctness of the concentrations were determined for this technique and compared with those from traditional methods. The signal-to-noise (S/N) ratios of the so-called “shadow spectra” were better than, or at least comparable to, the S/N ratios in the absorbance spectra obtained by using as background an air or an evacuated cell reference and subtraction of the spectra of water and carbon dioxide from a spectral library. The detection limits for the volatile organic compounds investigated have been improved by using this new method in which an appropriate background spectrum can be obtained quickly. The limitations of the method are that it cannot be applied to non-UV reactive compounds, such as methane, and the detection limits can be appreciably degraded when bands due to ozone in the shadow spectra overlap with those of the compounds under investigation.     

Raman spectroscopy of synthetic and natural iowaite

The chemistry of a magnesium based hydrotalcite known as iowaite Mg6Fe2Cl2(OH)16.4H2O has been studied using Raman spectroscopy. Iowaite has chloride as the counter anion in the interlayer. The formula of synthetic iowaite was found to be Mg5.78Fe2.09(Cl,(CO3)0.5)(OH)16.4H2O. Oxidation of natural iowaite results in the formation of Mg4FeO(Cl,CO3) (OH)8.4H2O. X-ray diffraction (XRD) shows that the iowaite is a layered structure with a d(001) spacing of 8.0 angtsroms. For synthetic iowaite three Raman bands at 1376, 1194 and 1084 cm(-1) are attributed to CO3 stretching vibrations. These bands are not observed for the natural iowaite but are observed when the natural iowaite is exposed to air. The Raman spectrum of natural iowaite shows three bands at 708, 690 and 620 cm(-1) and upon exposure to air, two broad bands are found at 710 and 648 cm(-1). The Raman spectrum of synthetic iowaite has a very broad band at 712 cm(-1). The Raman spectrum of natural iowaite shows an intense band at 527 cm(-1). The air oxidized iowaite shows two bands at 547 and 484 cm(-1) attributed to the (CO3)(2-)nu2 bending mode. Raman spectroscopy has proven most useful for the study of the chemistry of iowaite and chemical changes induced in natural iowaite upon exposure to air.     

The S1 <-- S0 spectrum of jet-cooled p-cymene

The spectrum of the first electronic transition of p-cymene cooled in a supersonic jet was measured by resonance-enhanced multiphoton ionisation (REMPI) in a time-of-flight (TOF) mass spectrometer. The band origin is strong and appears at 270.61nm (air value). This spectrum is useful for the detection of p-cymene in trace analysis.     

水溶性C60衍生物的电化学合成及表征

通过电化学方法合成了一种具有良好水溶性并能在水及空气中长期稳定存在的C₆₀衍生物,经电泳实验证实该衍生物带负电荷。红外光谱及近红外光谱显示该水溶物有稳定键合的CO和OH基,所以表现出强亲水性。在可见区(从420nm到700nm)有非常宽的发光谱带,这是由于Jahn-Teller效应以及C₆₀和OH基之间的相互作用引起的。