显微⁃傅里叶变换红外光谱鉴别分析微塑料

利用显微?傅里叶变换红外光谱技术分析鉴别了不同粒径及不同种类的微塑料（粒径小于5 mm的塑料、纤维或橡胶碎片）,系统阐述了反射、透射、衰减全反射3种测量模式及其微区成像技术在微塑料鉴别分析中的优缺点。基于显微?傅里叶变换红外光谱衰减全反射技术,分析了北京景观水样中的微塑料,结果表明该方法简单、准确、可靠。     

不同产地桔梗的红外光谱整体成分鉴别研究

采用傅里叶变换红外光谱法和显微红外光谱技术对不同产地桔梗进行鉴别。结果表明,不同产地桔梗的一阶红外光谱图整体上差别并不明显,二阶导数处理后,各产地的特征峰差异得以显现,显微红外光谱图则进一步直观清晰地显现出桔梗皂苷d的含量多少与分布区域,进一步佐证了不同产地桔梗间桔梗皂苷d的含量差异的结果。根据不同产地地理远近来分析,不同省之间的桔梗的物质含量与分布的差距比较明显;同省不同市之间几乎没有太大的差距,可能原因是同省不同市的地理距离太小。因此,红外光谱法和显微红外光谱技术提供了大量桔梗的整体化学成分信息,递进式地验证了不同产地桔梗之间的所含物质的量及分布有差异,可以初步鉴别不同产地桔梗,为今后系统完整的选择桔梗入药产地提供依据。     

红外光谱法在防晒化妆品鉴别研究中的应用

采用傅里叶变换衰减全反射红外光谱法(ATR-FTIR)对从不同渠道采集的6个同一品牌和系列的防晒化妆品进行分析,同时采用高效液相色谱仪对防晒化妆品样品中的防晒剂种类及其含量进行检测。结果表明,不同来源防晒化妆品样品的红外光谱图在防晒剂主要官能团结构上呈现较大差异,且与经高效液相色谱检测的防晒剂种类及含量结果具有较好的相关性。     

ATR-FTIR结合GC-MS鉴别印油种类

建立了一种傅里叶变换衰减全反射红外光谱法(ATR-FTIR)结合气相色谱-质谱联用法(GC-MS)鉴别印章印文的方法.结果表明,在波数4000～1700 cm-1范围内,根据其红外光谱图特征峰的个数及峰位置可将15种样品分为5类;结合气相色谱-质谱联用法,可以有效区分同一品牌不同型号及不同品牌不同型号的样品.该方法具有...     

防晒化妆品质量变化的衰减全反射傅里叶变换红外光谱研究

采用衰减全反射傅里叶变化红外光谱(ATR-FTIR)对不同配方组成的防晒化妆品进行了红外光谱鉴别并对其质量变化进行了追踪。结果表明,复配和单一防晒乳液因基质来源相同使得红外谱图的整体性和指纹性较为相似,但对其谱图进行二阶求导可放大各图谱指纹区间的差异用于配方组成差异较小的防晒乳液的鉴别。在6个月的加速实验中,同一乳液样品的红外谱图变化显著,且变化程度随着加速时间的增加而逐渐变大。依据空白乳液在加速过程中的谱图和相关系数变化情况,确定相关系数值0.980 0为此类化妆品红外检测时的整体质量变化临界值,即当红外谱图相关系数降至0.980 0时可认为产品的质量已发生明显变化,达到其有效期终点。由此可知,ATR-FTIR可以很直观地反映防晒乳液在其存储期间整体质量变化情况,是一种快速、科学的考察化妆品整体质量的方法。     

PP1330／LDPE共混体系的相分布研究

利用扫描电子显微镜、衰减全反射红外光谱及多种高聚物样品处理技术,研究了 PP1330/LDPE(1I2A)共混体系的相分布特点,观察到了体系中的两相贯穿现象,并讨论了两相贯穿现象和两相相容性之间的关系。     

使用红外光谱法和热重法分析硫化橡胶的成分

使用红外光谱法鉴定牌号为N402和C606两种硫化橡胶的主成分,并通过比较溶剂抽提前后和裂解前后的红外光谱和热重分析结果,得到了其中添加剂的信息。比较了裂解液透射分析法、裂解液衰减全反射(ATR)法和衰减全反射(ATR)直接法得到的红外光谱,结果表明:裂解液透射分析法和裂解液ATR法可以得到相似的红外谱图;裂解液透射分析法和裂解液ATR法得到光谱质量要高于ATR直接法。     

不同产地、不同种属黄精的红外光谱鉴别研究

采用傅里叶红外光谱技术结合二阶导数光谱对不同产地的黄精进行鉴别。研究结果表明,不同产地多花黄精的红外光谱图在整体上比较相似,其主要吸收峰均在3270、2933、1623、1411、1372、1319、1269、1103、1019、926、865、815 cm-1附近,但吸收峰的位置、峰强度等方面存在明显差异,在1018 cm-1附近是糖类的特征吸收峰,由红外光谱图可推测安徽省池州市、岳西县、江西省宜春市多花黄精中糖类成分含量较高,湖北省黄冈市、安徽省黄山区、石台县次之,安徽省休宁县、金寨县相对较少。6种黄精属植物的红外光谱图在吸收峰的位置、形状、强度等方面均有差异,故可推测黄精属不同植物在化学成分及含量上均存在明显差异。二阶导数图呈现出许多原始图谱中被掩盖的谱峰的变化特征,将谱图间的差异更为明显得表现出来,进一步提高了谱图的分辨率,与普通红外光谱图相比,二阶导数红外光谱图进一步直观地验证了上述结果。     

中空玻璃用密封胶红外光谱分析

采用衰减全反射(ATR)红外光谱法,测试不同型号的中空玻璃用硅酮密封胶和聚硫密封胶的红外光谱,分析密封胶的红外光谱主要吸收峰和对应的基团,指出了鉴别中空玻璃用硅酮胶和聚硫胶的红外光谱特征峰,进而可快速鉴别密封胶类型.     

不同聚合度EVOH降解行为研究

利用溶度分级原理对乙烯-乙烯醇共聚物(EVOH)商品料进行分级,获得乙烯含量接近、聚合度不同的四个级分,并采用200℃热氧处理0~40 min的方法对不同聚合度样品进行热氧处理。通过核磁共振氢谱(H NMR)、特性黏数、差示扫描量热仪(DSC)表征了样品结构信息,采用热重分析(TGA)对比不同聚合度样品的热稳定性差异。利用傅里叶变换衰减全反射红外光谱法(ATR-FTIR)、紫外光谱(UV)表达不同聚合度样品在热氧处理过程中的结构变化。实验发现,四个样品在热氧处理过程中,O-H的含量都在减少,C=O与共轭双键的含量不断增加,并且聚合度高的样品更容易生成共轭双键,聚合度低的样品更容易生成C=O。     

Analysis and monitoring oftrans-isomerization by IR attenuated total reflectance spectrophotometry

Attenuated total reflectance for IR determination oftrans-isomers in fats appears to have distinct advantages over procedures currently used. The AOCS standard method CD 14-61 requires weighing and quantitative dilution of a sample with carbon disulfide before spectrophotometric analysis at 10.3 μm. In contrast, according to the attenuated total reflectance analytical procedure, one neither weighs nor dilutes but merely fills the cell with oil and reads at 10.3 μm. In addition to analyses fortrans-isomers in liquid oils, margarines and shortenings, attenuated total reflectance enables one to monitortrans-development continuously during hydrogenation. The presence of catalyst in unfiltered hydrogenated oils does not interfere with attenuated total reflectance measurements in contrast to classical transmission measurements. Unfiltered oil from the hydrogenator can be circulated through the attenuated total reflectance cell to recordtrans-isomerization during the reaction. ARS, USDA.     

硅橡胶泡沫伽马辐照后结构和元素分布研究

在密闭的氮气气氛下,用伽马射线辐照聚二甲基硅橡胶泡沫,采用全反射红外光谱(ATR)和X射线光电子能谱(XPS)对辐照后的化学结构和元素含量变化进行了表征.结果表明:化学结构单元Si-CH3最容易受到伽马射线的影响,在低的辐照剂量下表面Si-CH3成分随着辐照剂量增加而减小;高剂量下材料的元素分布发生了变化,近表面C元素含量要比泡沫体中部的C元素含量高.因此,在密闭环境下辐照老化后的硅橡胶泡沫的表面性能和体内性能存在差异.     

Surface interaction between aluminum and epoxy resin

Titration and infraed analysis found no primary chemical bonds between etched or unetched aluminum and an amine-cured epoxy resin. Titration of a very small amount of resin in contact with the large surface area of aluminum dust revealed no drop in epoxy content when oxygen was excluded. The spectra of a bulk-cured epoxy resin were essentially superimposable on the spectra obtained by attenuated total reflectance and specular reflectance of a very thin layer of the cured epoxy resin bonded to aluminum plate. Analysis of uncured epoxy resin in contact with aluminum plate and powder, subjected to the cure cycle in air, indicated that the epoxy ring is oxidized to a carboxylic acid. When air is excluded, no loss of epoxy groups is observed.     

Structure and oil‐resistant properties of HTPB‐based polyurea modified with polysulfide

A series of hydroxy‐terminated polybutadiene (HTPB) polyureas modified with different liquid polysulfide content was synthesized and their structure and oil‐resistant properties were studied by attenuated total reflectance–FTIR spectroscopy, dynamic mechanical analysis, isothermal aging and differential scanning calorimetry, stress–strain analysis, oil absorption, and oil‐resistance test. The results showed that polysulfide–polybutadiene polyureas retained low temperature flexibility and had lower oil absorption and better oil resistance than that of HTPB‐based polyureas. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 89: 2672–2675, 2003     

Curing of mixtures of epoxy resins and 4‐methyl‐1,3‐dioxolan‐2‐one with several initiators

Diglycidyl ether of bisphenol A or 3,4‐epoxycyclohexylmethyl 3,4‐epoxycyclohexane carboxylate were mixed with different proportions of 4‐methyl‐1,3‐dioxolan‐2‐one and cured using lanthanide triflates as initiators. In order to compare the materials obtained, conventional initiators such as boron trifluoride complexes and N,N‐dimethylaminopyridine were also tested. The curing process was followed by differential scanning calorimetry (DSC) and Fourier transform IR in attenuated total reflectance mode. This technique proved that the carbonate accelerates the curing process because it helps to form the active initiating species, although it was not chemically incorporated into the network and remained entrapped in the material. The DSC kinetic study was also reported. © 2006 Wiley Periodicals Inc. J Appl Polym Sci 102: 2086–2093, 2006     

Classification of Four Almond Cultivars Using Oil Degradation Parameters Based on FTIR and GC Data

Four almond cultivars (Marcona, Guara, Garrigues and Butte) have been classified using attenuated total reflectance Fourier transform infrared spectroscopy (ATR-FTIR) and gas chromatography (GC) data. The data were obtained by completing the first stages of a thermal oxidative degradation process. The degradation process was monitored by using the variations in the main fatty acid methyl esters (FAME) content determined by GC and to changes in the infrared spectra recorded using the ATR-FTIR technique. In order to classify the almond cultivars, a stepwise linear discriminant analysis was applied to the data. The results indicated that, although the four almond oils evaluated here have a similar fatty acid composition, differences in linoleic acid content may be linked to oxidative stability. Butte cultivar samples had higher linoleic acid content and were more prone to oxidative deterioration.     

FTIR-OMNI采样器快速分析材料表面涂层聚合物成分

采用傅里叶变换红外光谱(FTIR)仪的衰减全反射(ATR)附件——OMNI采样器,对45#钢、山羊皮革、易拉罐内壁、空白光盘等4种材料表面的聚合物涂层进行了ATR-FTIR分析。结果表明,该方法无需对样品进行前处理,适用于生产、科研、质检等部门快速分析材料表面涂层的聚合物成分,具有简便、准确、无损的特点。     

Characterization and microstructure study of low‐density polyethylene by Fourier transform infrared spectroscopy and temperature rising elution fractionation

Infrared spectroscopy is a powerful technique for studying the microstructure and determining the short‐chain branch distribution of polyethylene. In this work, the types and amounts of short‐chain branches in low‐density polyethylene were investigated with Fourier transform infrared spectroscopy, and a new and simple method for the determination of butyl short branches was discovered. The amount of each unsaturated species in low‐density polyethylene was also determined with Fourier transform infrared after the bromination of samples. Furthermore, the resin was fractionated by preparative temperature rising elution fractionation, and the branch distribution and melting endotherm of each fraction were analyzed with attenuated total reflectance/Fourier transform infrared and differential scanning calorimetry. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2008     

In situ FT-IR spectroelectrochemical study of electrooxidation of pyridoxol on a gold electrode

The electrochemical oxidation of pyridoxol (PN) on a polycrystalline gold electrode was investigated by cyclic voltammetry and in situ Fourier transform infrared spectroscopy (FTIRS). In 0.1 M aqueous NaOH solution, the gold electrode showed a high catalytic activity for the irreversible oxidation process of PN. The individual ionic species and the major tautomeric equilibria of PN molecules in aqueous solutions were evidenced well from the pH-dependent attenuated total reflectance (ATR) spectra, and the results were in good agreement with the voltammetric observations. In situ single potential alteration infrared reflectance spectroscopy (SPAIRS) demonstrated that a lactone form of PN, rather than pyridoxal aldehyde, was likely formed, which was subsequently diffused into the thin layer solution and underwent hydrolysis slowly to pyridoxic acid (PA) as the final product. In addition, the adsorption of PN at Au electrode was characterized by in situ subtractively normalized interfacial Fourier transform infrared reflectance spectroscopy (SNIFTIRS) method, which revealed that the adsorption of deprotonated PN, via nitrogen atom in vertical configuration on electrode surface, occurred from −0.5 V versus Ag?AgCl?KCl(sat), which was much lower than the potential of PN electrooxidation observed from ca. 0 V.     

残余碳对碳化硅陶瓷光学表面加工性能的影响

为深入了解碳化硅陶瓷的光学表面加工性能,采用常压固相烧结法制备了碳化硅陶瓷,在保证致密度的前提下,通过改变碳的含量,研究了残余碳对SiC陶瓷抛光面的表面质量和光学性能的影响。研究发现,C的质量含量为3%～7%时,SiC陶瓷抛光表面的RMS(root mean square)粗糙度均约为2nm。当C含量为3%～6%时,SiC陶瓷抛光表面在400～750nm波段的全反射率、漫反射率和镜面反射率无明显变化;当C含量升至7%时,全反射率稍有降低,漫反射率稍有上升,镜面反射率稍有降低。其原因可能是过多的残余碳引起SiC陶瓷的折射率下降和产生光学散射,最终造成镜面反射率降低。