红外光谱技术在食品检测中的应用

过去十年中,红外光谱在全球食品工业中的应用已呈现出快速的增长趋势。傅立叶变换红外光谱(FTIR)技术得到许多研究者青睐。尤其是化学计量学方法在提取光谱信息和排除背景干扰方面取得良好效果后,人们重新认识红外光谱技术的价值,使红外光谱在食品检测中的应用得到快速发展。本文就红外光谱技术的原理和特征及相关专家学者对其在食品检测方面应用的研究成果进行综述,以期为食品企业的检验分析工作者在引进傅立叶红外光谱仪时提供参考。     

浅谈傅立叶变换红外光谱技术与应用

红外光谱法是进行材料分析及监控的有力手段,介绍了傅立叶变换红外光谱技术与应用。     

傅立叶变换红外光谱仪波数示值误差的不确定度评定

傅立叶变换红外光谱仪广泛应用于医药化工、地矿、石油、煤炭、环保、海关、宝石鉴定、刑侦鉴定等领域对样品进行定性和定量分析,本文对傅立叶变换红外光谱波数示值误差的不确定度进行评定分析。     

全氟磺酸树脂中不稳定端基的热行为研究

用傅立叶变换红外光谱和热失重方法对全氟磺酸树脂中的不稳定端基的热行为进行了研究。     

塑料牙刷柄的傅立叶变换红外光谱分析

本文采用傅立叶变换光谱法对13种不同品牌的白色牙刷柄塑料进行了红外光谱分析,实验结果表明,依据红外光谱数据的异同,能够对不同品牌的牙刷柄样品进行鉴别。     

高光谱成像与应用技术发展

介绍了高光谱成像的需求与应用、光谱成像技术的现状与发展。高光谱成像已在产品分选、精准农业、环境监测、文物保护、刑事侦查、伪装识别等行业得到应用。传统的棱镜光栅色散型、连续可调谐滤光型、傅里叶变换干涉型等光谱成像分光方式成本高、体积大、速度慢,目前其光谱成像仪仍作为主要的研究设备。为促进产业化应用,需要发展体积小、成本低、速度快的光谱成像技术。计算层析、压缩编码、胶体量子点CQDs光谱成像技术仍需理论突破,短时间难以实用。积分视场、离散采样光谱成像技术原理简单、技术成熟,可用于空间分辨率要求不高的场合。复眼滤光式、像素滤光式光谱成像技术通过单片集成像素级滤光片,既能在权衡光谱分辨率与空间分辨率的基础上实现实时性,又能极大地减小体积、降低成本。     

实时观察反应过程 利用变角衰减全反射傅立叶变换红外光谱法（ATR-FTIR）对聚缩反应过程进行实时跟踪观察

ReactIR在线红外光谱分析技术允许直接对化学反应过程进行跟踪观察，这种光谱分析技术的基础是一个变角衰减全反射傅立叶变换红外光谱仪。在原位反转录聚合酶链式反应分析技术中，光谱仪经光导折射系统与反应釜中的检测传感器连接在一起。本文介绍了这种技术在聚磺合成过程中定性的和定量分析的应用情况。[编者按]     

低浓度苯系物气体的FTIR定量分析方法

苯系物是室内空气污染的重要组成部分,本文运用傅立叶变换红外（FTR）光谱技术研究苯系物的红外吸收光谱特征,确定光谱分析时各组分的特征红外波长,采用美国热电子OMNIC Quant Pad分析软件建立了低浓度（0～5×10^-6）苯系物包括甲苯,邻、间、对二甲苯,苯乙烯,硝基苯的定量分析方法和校准曲线数据库,并应用于样品气检测,结果表明该方法具有较高的准确度和较好的应用推广前景。     

微量特种气体的FT-IR定量分析

利用傅立叶变换红外光谱法对微量一氧化氮、二氧化氮、氧化亚氮、氨气、氯化氢、二氧化硫、二氯氢硅、三氯氢硅、四氯化硅等使用常规方法分析难度大、灵敏度不足、操作复杂的气体样品进行了定量分析.在恒定实验条件下进样,分辨率为4 cm-1,扫描8次,可以得到理想的分析结果.以氨气、一氧化氮和二氧化氮为例的定量分析结果表明,该方法重...     

显微红外光谱热分析PTT的熔融过程

采用显微傅立叶转换红外光谱技术研究了聚对苯二甲酸丙二酯（PTT）的熔融相转变过程。通过采集40℃～250℃连续程序升温过程的显微红外光谱数据,运用在等压条件下的van’t Hoff关系式推导计算特征基团在升温熔融过程中起点和终点振动的两种能态吸光度比值的变化和振动能态转变的表现焓变（△H）。研究了PTT分子链段中各基团对熔融过程的贡献。从计算得到的各种特征基团在两种能态吸光度的表现焓变△H的数据可知,PTT链段中的各种振动模式对PTT的熔融过程都有不同程度的贡献。     

From Industry 4.0 to Research 4.0. Development of High Performance Fibers in the Light of Digitization

We associate a variety of innovations with the term ＂Industry 4.0＂. The pioneer of many 4.0 modifications forms the basisfor the trend towards the integrated di...     

Roman iron and steel: A review

ABSTRACT

The production of ferrous metal increased during the Roman Late Republican period, Principate and Empire. The direct bloomery process was used to extract the metal from its ores using slag-tapping and slag-pit furnaces. The fuel was charcoal and an air blast was introduced by bellows-operated tuyères. Iron formed as a bloom, often as a spongy mass of metal, which contained impurities from the smelting process, including unreacted ore, fuel, slag and fragments from the furnace walls, while the metal was often inhomogeneous with varied carbon contents. Blooms were either smithed directly into bars or ingots or they were broken up, which also allowed the removal of gross impurities and a selection of pieces with similar properties to be made. These could then be forge-welded together and formed into characteristically shaped ingots. Making steel in the furnace seems to have been achieved: it depended on the ore and the furnace and conditions within it. Surface carburization was also carried out. Iron and steel were used extensively in construction and for tools and weapons. Fire welding was often used to add pieces of steel to make the edges of tools and weapons, which could be heat-treated by quenching to harden them.     

Certification Institutions Expected to Update and Transfer Information on Present Standards

Standards are the basis for production enterprises to organize production, ex-factory inspection, trade (delivery) and technical exchanges, product certification, quality arbitration and supervision.……     

The Research of Anti-Wear Properties of Organomolybdenum Compounds in the Engine Oils

A four-ball tester was used to evaluate the anti-wear performance of three kinds of organomolybdemun compounds in the engine oils, i. e., molybdenum dialkyldithiophosphate (MoDDP), molybdenum dialkyldithiocarbamate ( MoDTC), and sulphur and phosphorus freeorganomolybdeum (Molybdate). The results indicate that a low concentration of MoDDP doesn' t improve the anti-wear properties of the commercial engine oils, but a high concentration of MoDDP can obviously improve the anti-wear properties and the load-carrying capacity of the engine oils. MoDTC doesn' t improve the antiwear properties of the engine oils, but worsens the anti-wear properties of the oils. Signifi can timprove ment of frictional and wear characteristics is obtained with Molybdate added in the commercial engine oils and the formulated oils.     

Synthesis of Alumina-Zirconia Nanocomposites by Solgel Process

Al₂O₃-ZrO₂ nanocomposites were developed starting with the solgel process. Composite alumina-zirconia nanopowders were synthesized from metallorganic precursors (Aluminium secondary butoxide and zirconium Iso propoxide) using the solgel process. The parameters affecting the synthesis—solvent, concentration of precursor, R/H ratio (i.e., dilution of water in solvent)—were varied as also the temperature and pH. BET and TEM were used to measure nanosize. Diffuse reflectance spectroscopy and also qualitative optical absorption led to identical particle size estimate. The variation of process parameters was used to study the effect and interdependence of process parameters. Artificial Neural Networks was used to rigorously analyze the process. Although this led to confirmation of interdependence of parameters, the presence of a single overwhelming solvent variable was also established. Then the optimal process was used to synthesize more nanopowder. To produce bulk nanocomposite the nanopowders were sintered by varying the temperature and time period. The sintered lithoids were probed with a vickers hardness tester to measure elastic modulus, hardness, and fracture toughness. The results showed high elastic modulus, modest hardness, and very high fracture toughness.     

Friction Stir Processing Strategies for Uniform Distribution of Reinforcement in a Surface Composite

Friction stir processing (FSP) is an important technique for preparing surface composites. Fabricating defect-free surface composites with uniform particle distribution by FSP is a challenging task. In this study, silicon carbide particles reinforced AA5083 alloy surface composites was fabricated using different FSP strategies including variation in process parameters, dual-tool processing and tool offset overlapping. Material flow of the processed material with reinforcement particles demonstrated that the distribution of particles was influenced by the stirring action of the probe as well as the extrusion of the plasticized material due to the movement of the tool. Process parameters, particularly rotational speed, showed a dominant influence on the distribution of silicon carbide particles.     

Optimum-Simulation von Ernteprozessen

Zusammenfassung Bei der Gestaltung von Ernteprozessen — beispielsweise des Prozesses Mähdrusch, Körnertransport und -abnahme — als transportverbundene Fließarbeitsverfahren mit mindestens zwei verschiedenen Arbeitsmitteln gibt es einen großen Optimierungsspielraum. Solche Prozesse sind mehrstufige Bedienungsprozesse mit gemischter Anordnung der Bedienungseinrichtungen. Außerdem besitzen sie stark ausgeprägte räumliche Aspekte. Es wird vor allem gezeigt, welche Merkmale solcher Prozesse in Simulationsmodellen abgebildet sein müssen, welche Zielgrößen in Abhängigkeit von welchen Einflußgrößen unter Berücksichtigung welcher Prozeßbedingungen ermittelt werden sollten und wie der Bewertungsprozeß zur Ermittlung der gewünschten Informationen gestaltet werden muß.     

Certification Becomes Important for the I Quality; and Safety Supervision of the Chinese Liquor Sector

The end of 2007, over 200 unit products of more than 80 Chinese firms have passed the quality grade certification for liquor products. These products involve distilled spirits, beer, wine, yellow wine, fruit syrup wine and others, and cover over 80% of the national top-branded liquor products.……     

Deposition and Coating Properties on CVD Tungsten

Surface characterization and microstructure studies are performed on chemical vapor deposited (CVD) tungsten coating. There is about 2 μm thickness diffusion layer of tungsten in the molybdenum substrate. The thermal shock test shows tungsten coating has good adhesion with molybdenum substrate, but the elements of oxygen and carbon in the tungsten coating have the bad affection to the adhesion. The result of high-temperature diffusion experiment is the diffusion rate from molybdenum substrate to tungsten coating is faster.     

Instructions & Forms for Authors

Journal of Materials Sciences ＆ Technology is a monthly journal for the rapid dissemination of new, impor- rant results in material and related fields. Submission Electronic files of MS Word and PDF are acceptable. Please visit http：//www.jmst.org and submit online.