bluuebunny/crossref_metadata_2025_split huggingface dataset:
Depth Profiling by Microspectroscopy
Authors: Fredericks Peter M. 
Published: September 2006

Abstract
This chapter discusses the use of infrared (IR) and Raman microspectroscopy to investigate the structural variation with depth of solid samples. For IR spectroscopy the common approach is destructive, in that the sample is sectioned and the spectra are collected along the exposed face using transmission, reflection, or attenuated total reflection (ATR) methods. IR microspectroscopy does not lend itself to useful nondestructive approaches, except in the case of the ATR objective, which allows for a small degree of depth profiling by applying internal reflection elements of different refractive indexes leading to a change in the penetration depth. In contrast, Raman microspectroscopy is well suited to depth profiling studies. In the case of destructive approaches, it is similar to IR but has a much higher spatial resolution of about 1 µm compared with a practical limit of 10 µm or more for IR. Because of the confocal nature of many Raman microspectrometers there is also the possibility of resolution along the optical axis so that the signal results from around the focal plane only. If the microspectrometer is operated in confocal mode it is possible, without any sample preparation, for spectra to be collected from within the sample, a process known as “optical slicing”. While there have been some reports demonstrating the efficacy of this approach, there have also been warnings relating to the accuracy of the method. Theoretical ray tracing analysis indicates that inaccuracies exist in the definition of the sampling volume and its depth within the sample.
Gas Chromatography/
F
ourier Transform Infrared Spectroscopy
Authors: Visser Tom 
Published: September 2006

Abstract
The article describes the principles, potentials, and limitations of infrared (IR) spectroscopy as a detector in gas chromatography (GC) in an analytical context. The instrumentation part comprises interfacing of the IR spectrometer and the GC by means of a lightpipe based on a gas‐phase flow cell and two sample storage techniques, that is, matrix isolation and direct deposition which are based on freezing the eluates on a moving substrate. Next to technical aspects, attention is given to instrument optimization in terms of restrictions put by preceding chromatographic requirements. Furthermore, tools for data acquisition, processing, and quantitative and qualitative interpretation are presented. It is concluded that IR can be used as a universal, selective, and specific detector, but a drawback is the lack of sensitivity. However, GC‐IR can supply unique structural information that cannot be obtained from any other method. The latter is illustrated by a number of applications covering environmental analysis, pharmaceuticals and drugs, polymers, food constituents, and biological compounds.
High‐Performance Liquid Chromatography/
F
ourier Transform Infrared Spectroscopy
Authors: Kalasinsky Kathryn S. , Kalasinsky Victor F. 
Published: September 2006

Abstract
The sections in this article are

Introduction

Design Considerations for

HPLC

/

FT
‐
IR

Infrared Spectroscopy

High‐Performance Liquid Chromatography

HPLC

/

FT
‐
IR

Interfaces

Flow‐Cell

HPLC

/

FT
‐
IR

Solvent‐Elimination

HPLC

/

FT
‐
IR

Applications

Proteins

Beverages

Pharmaceutical Samples

Environmental

Polymers –

GPC

/

SEC

Multiple Interfaces

Current Status

Acknowledgments
Thermal Analysis‐IRMethods
Authors: Hellgeth John W. 
Published: September 2006

AbstractThe sections in this article areIntroductionTAMethodsEGADTADSCTGASTAIRSpectrometryEGAwithIRSpectrometryEvolved Gas Trapping TechniquesEGAUsing a Flow CellDisplay and Manipulation of Spectral InformationEGA‐IRApplicationsApplication ofEGA‐IRofPVCvia ThermogravimetryAdvancedEGA‐IRMethodsCondensed PhaseDSC‐IRMethodsSummary
Mid‐Infrared Spectroscopy: Anomalies, Artifacts and Common Errors
Authors: Chalmers John M. 
Published: September 2006

Abstract

Understanding, appreciating and recognizing the influences that anomalies, artifacts and common errors have on the appearance and spectral contrast of a mid‐infrared spectrum is vital if data are to be interpreted and quantified correctly. This article presents examples of some of the common imperfections that may be observed in mid‐infrared spectra, and discusses concisely their origin. It covers the effects of atmospheric intrusion (water vapour and carbon dioxide), and the influences of stray light on the spectra of both liquid and solid samples. It includes a discussion of the superimposition on a spectrum of a sinusoidal waveform, such as ‘channel spectra’ sometimes seen in high‐resolution gas phase spectra or ‘interference fringes’ observed in polymer film transmission spectra. Simple examples of spectra of common contaminants are poly(dimethyl siloxane) – silicone grease/oil‐, phthalate plasticizers from poly(vinyl chloride) (PVC) sources – gloves, pipes ‐, and nitrate from non‐spectroscopic grade KBr. The effects of anomalous dispersion (Christiansen effect) and scatter are illustrated for both a KBr disk and a Nujol
®
mull spectrum; the influence of anomalous dispersion and angle of incidence on attenuated total reflection (ATR) spectra is also discussed, as is the overlay of a specular reflection spectrum on diffuse reflection and transflection spectra. The influence of particle size on spectral contrast for a range of sample presentation methods is illustrated. The origins of saturation effects in photoacoustic FT‐IR spectra, inverted bands in emission spectra, and diffraction effects in FT‐IR microscopy measurements are outlined. Other considerations include choice of single‐beam background, detector non‐linearity, data manipulation, plot software characteristics, instrument linearity, and external reflection mixed‐mode spectra.
Anomalies and Artifacts inRaman Spectroscopy
Authors: Bowie Bryan T. , Chase D. Bruce , Lewis Ian R. , Griffiths Peter R. 
Published: September 2006

AbstractThe sections in this article areIntroductionInstrumental EffectsLaser OutputFilter EffectsShifts in the Wavenumber ScaleAliasingMulti‐Passing ErrorsDetector EffectsNoise EffectsDark Noise“Hot Pixels” and Cosmic RaysSummaryEffect of SampleIntroductionSample HeatingFluorescenceMatrix AbsorptionSamplingIntroductionAmbient LightingAirSample Support SurfacesSample Containers – GlassSample MovementConfocal Depth AnalysisPolarizationSummaryAcknowledgments
Spectra– Structure Correlations in the Near‐Infrared
Authors: Weyer L.G. , Lo S.‐C. 
Published: September 2006

Abstract
The sections in this article are

Introduction

Hydrocarbons

Aliphatic Hydrocarbons

Aromatics

Olefins

Amines and Amides

Hydroxyls

Alcohols

Phenols

Multiple Hydroxyl Compounds

Carboxylic Acids

Hydrogen Peroxides

Water

Liquid Water, Ice, and Water Vapor

Water in Various Solvents

Water in Other Matrices, Including Glasses

Ionic Species in Water

Carbonyl Compounds

Miscellaneous

Acknowledgments
Spectra–Structure Correlations: Polymer Spectra
Authors: Chalmers John M. , Hannah Robert W. , Mayo Dana W. 
Published: September 2006

Abstract
Features within an infrared (IR) or Raman spectrum recorded from an organic polymer may yield information on chemical structure and composition, isomerism and stereoregularity, conformational order, molecular orientation and state of order.

This article discusses spectra‐structure correlations, both generic (e.g. polyethylene; polybutadiene) and detailed (e.g. high density, low density and linear low density polyethylene;1,4
cis
‐, 1,4‐
trans
and 1,2‐ polybutadiene ), within polymer mid‐infrared and Raman spectra, using as examples for interpretation a range of common polymer types. It considers the influences on polymer and copolymer vibrational spectra of the effects of tacticity, regularity, molecular conformation and orientation, and crystallinity, and discusses copolymer sequence lengths and end group characterisations. The article concludes with examples of spectra recorded from formulated products highlighting the contributions some additives and fillers may make to the observed vibrational spectra of commercial polymer products.
Normal Coordinate Analysis
Authors: Groner Peter 
Published: September 2006

Abstract
The chapter summarizes important concepts from the theory of molecular vibrations of which normal coordinate analysis is a part. Section 2 describes how molecular vibrations or, more precisely, harmonic oscillators are treated in classical mechanics and how normal coordinates are defined. The quantum mechanics of coupled harmonic oscillators, which is based on normal coordinates, is developed in section 3, together with the selection rules for infrared and Raman spectroscopy. It is followed by excursions into some applications of symmetry concepts and into the domain of real molecules where harmonic oscillators are satisfactory approximations at best (anharmonicity and large‐amplitude internal motions). Section 4 introduces the commonly used internal and symmetry coordinates, the transformations between them and the Cartesian and normal coordinates, Wilson's GF method of normal coordinate analysis, and discusses redundant sets of internal coordinates. A short survey of force fields past and present (central, valence, and Urey‐Bradley force fields and force fields from semiempirical and ab initio calculations) is given in section 5. The invariance of internal coordinates, the transformation from internal to Cartesian coordinates, and some aspects of redundant coordinates are detailed in appendices.
Introduction to Factor‐Based Approaches
Authors: Kvalheim Olav M. 
Published: September 2006

Abstract
The sections in this article are

Introduction

Development of Chemometrics

“Making Each Piece of Data Work Twice”

The One‐Variable‐at‐a‐Time Approach in the Presence of Correlation

The One‐Variable‐at‐a‐Time Approach in the Presence of Interaction

Information as a Function of Experimental Strategy

The Latent Variable

Resolution of Multicomponent Profiles

Chemometrics in Society

Chemometrics, Analytical Chemistry and Infometrics

Conclusion

Acknowledgments
Discriminant Analysis
Authors: Fearn Tom 
Published: September 2006

Abstract
The sections in this article are

Introduction

Linear Discriminant Analysis with Two Groups

M
ahalanobis Distance

Extension to Several Groups

Coping with Large Numbers of Spectral Variables

LDA
on Principal Components

Relation between

LDA

and Multiple Regression, and Using Partial Least Squares for Discrimination

Logistic Regression

Validation

Some Limitations, Extensions and Other Approaches

Applications
General Theory of Two‐Dimensional (2
D
) Analysis
Authors: Noda Isao 
Published: September 2006

Abstract
In two‐dimensional (2D) correlation vibrational spectroscopy, a spectrum defined by two independent spectral variables (e.g., wavenumber) is generated by applying a correlation analysis to a series of systematically varying spectra measured under an external physical perturbation. Because of the well‐known specificity of spectral features of infrared (IR) and Raman to chemical constituents of the system, perturbation‐induced variations of spectral signals contain surprisingly rich information about the unique behavior of individual chemical moieties comprising the system. Some of the notable features of 2D correlation spectra are: simplification of complex spectra consisting of many overlapped peaks, enhancement of spectral resolution by spreading peaks over the second dimension, establishment of unambiguous band assignment through correlation of bands selectively coupled by various interaction mechanisms, and determination of the sequential order of events depicted by asynchronous changes in spectral intensities.
Resolution Enhancement Approaches
Authors: Saarinen Pekka E. , Kauppinen Jyrki K. 
Published: September 2006

Abstract
The sections in this article are

Fourier Transform and Impulse Response

Definition and Discretization of Fourier Transform

Continuous Fourier Transform and the Dirac Delta Function

Some Useful Fourier Transform Pairs

The
Discrete Fourier Transform
(

DFT

)

Signal Discretization Effects: Spectral Aliasing and Resolution

Convolution, Impulse Response, and Linear Prediction

Convolution, Impulse Response, and Line Shape

Discrete Convolution

Transfer Function and Causal Impulse Response

Forward and Backward Linear Prediction

Frequency Estimation from the Impulse Response

Eigenanalysis Approach to Frequency Estimation

The Minimum Norm Method

MUSIC

(Multiple Signal Classification)

Resolution Enhancement without Signal Extrapolation

Fourier Self Deconvolution

Derivatives in Resolution Enhancement

Prony's Method

Maximum Entropy Power Spectral Estimator

Resolution Enhancement by Signal Extrapolation

Extrapolation Without Impulse Response: the Minimum Negativity Method

Signal Extrapolation with Impulse Response

Computation of the Impulse Response

The Matrix Methods

The Levinson–Durbin Recursion and Burg's Formula

Theoretical Impulse Response

LOMEP

(
Line Shape Optimized Maximum Entropy Linear Prediction
)

Frequency Tuning Method
Principal Component Regression and Partial Least Squares Modeling
Authors: Hasegawa Takeshi 
Published: September 2006

AbstractThe sections in this article areIntroductionData Modeling by Latent VariablesDecomposition of Spectral Data Using Latent VariablesLeast Squares Regression by Matrix Algebra“Partial”CLSto Yield a Principal ComponentPrincipal Component RegressionsComparison ofCLSandILSGenerate Factors byPCAforILSProtocols ofPCRCalculation Steps ofPCRCalibrationCalculation Steps for Concentration Prediction byPCRSelection of Significant FactorsAnalysis of ErrorEmpirically Defined Method of Error EstimationStatistical Method for Error EstimationSelection by ValidationAbstract Spectra and ResidualsOptional PretreatmentMean CenteringScalingNormalizationPartial Least Squares RegressionPLS2 (GlobalPLS)PLS2 CalibrationDiscussion of thePLS2 AlgorithmSelection of Basis Factors forPLSModelingPLSPredictionPLSModeling by Eigenvector CalculationPLS1 (StandardPLS)Comparison ofPLS2 withPLS1Comparison ofPLSwithPCR
Data Transfer
Authors: Davies Antony N. 
Published: September 2006

Abstract
The sections in this article are

Introduction

Data Storage and Archiving

Short‐Term Spectroscopic Data Storage

Regulatory Issues

Individual Spectrometer File Formats

Third‐Party Software House Data Formats

Mid‐ and Long‐Term Spectroscopic Data Storage

The

JCAMP
‐
DX

Standard

Chemistry and the Internet

Chemical
MIME

CML

Conclusions
Qualitative and Quantitative Analysis of Polymers and Rubbers by Vibrational Spectroscopy
Authors: Chalmers John M. , Everall Neil J. 
Published: September 2006

AbstractThis article begins with a short introduction on the range of sample forms, types and properties. This is followed by concise descriptions of the various sampling techniques as they apply to polymer analyses by mid‐infrared and Raman spectroscopy. (The article does not cover near‐infrared spectroscopy). More specific applications sections then follow discussions of qualitative and quantitative analysis and peculiarities associated with polymer mid‐infrared and Raman spectra. These include measurement of molecular orientation, determining end group concentrations and branching, studies of hydrogen bonding and blend miscibility, copolymer composition, polymerisation and cure studies, degradation and oxidation, and determining optical properties and constants. Brief sections are included also on chromatography coupled with FT‐IR, EGA/FT‐IR and TGA/FT‐IR and pyrolysis‐infrared. Discussed also are 2D‐IR, process measurements and microspectroscopy applications. This article is essentially a prelude to the more specialised articles that follow on in this section (Analysis and Characterization of Polymers and Rubbers) in this Handbook.
Measurement of the Solar Properties of Polymers by Vibrational Spectroscopy
Authors: Papini M. , Papini F. 
Published: September 2006

Abstract
The sections in this article are

Introduction

Solar Radiation

Air Mass

Extraterrestrial Solar Radiation on a Horizontal Surface and Attenuation By the Atmosphere: Spectral Properties

Estimation of Clear Sky Radiation

Conclusions

Solar Radiation Measurement

Pyrheliometer

Pyranometer

Diffuse Radiation

Sources of Measurement Error

Detection of Infrared Radiation

Measurement of Solar Radiative Properties

Spectral and Solar Properties

Direct Measurement of Solar Properties

Radiative and Thermal Balance of a Solar Collector

Synthetic Presentation: the Greenhouse Effect

Radiation Transmission through Covers

Collector Top Loss Coefficient

Polymers as Cover Systems

Honeycomb Structures

Polymers as Protective Coatings

Photocells and Conductive Polymers

Conclusions
Determination of Optical and Dielectric Properties of Polymers by Vibrational Spectroscopy
Authors: Smith D.M. , Chughtai A.R. 
Published: September 2006

AbstractPrinciples of refraction and extinction of electromagnetic radiation incident upon homogeneous isotropic condensed phases are reviewed. The relation between the complex refractive index,n(ν), and the attenuation constant,k(ν), through the Kramers–Kronig transform is shown as is the relation of these optical constants toɛ, the complex dielectric function. The basis of the determination of the optical constantsnandkas a function of frequency for transparent amorphous polymeric materials by reflection absorption infrared spectroscopy (RAIRS) is illustrated with examples. Also discussed is the effect of absorber concentration on the RAIR spectra. Various methods for the measurement of the optical constants and dielectric function of isotropic polymers included are other reflectance methods, attenuated total reflectance (ATR), transmittance–reflectance, transmission, and ellipsometry. The incipient importance of approaches for determining anisotropic optical constants is noted.
Rheo‐Optical
F
ourier Transform Infrared Spectroscopy of Polymers
Authors: Kalkar A.K. , Siesler H.W. , Zebger I. , Pfeifer F. , Ameri A. , Michel S. , Hoffmann U. 
Published: September 2006

Abstract
This chapter describes the experimental principle and the basic theory of rheo‐optical Fourier transform infrared (FT‐IR) and Fourier transform near‐infrared (FT‐NIR) spectroscopy for the characterization of transient microstructural changes during polymer deformation and stress relaxation. To demonstrate the high potential and the versatility of these techniques, the data obtained from select polymer systems are analyzed and discussed in some detail. In poly(dimethylsiloxane)/polycarbonate (PDMS/PC) block copolymers, for example, depending on the composition and the block lengths, different orientational and recovery phenomena have been observed for the hard (PC) and soft (PDMS) segments. Furthermore, the strain‐induced crystallization of a poly(etherurethaneurea) elastomer system has been successfully monitored during cyclic elongation and recovery. Finally, the versatility of the method has been demonstrated for the characterization of orientation and orientational relaxation in bimodal blends of poly(methylmethacrylate) (PMMA).
Infrared Characterization of Device‐Quality Silicon
Authors: Medernach John W. 
Published: September 2006

Abstract

Vibrational spectroscopy is the major optical characterization technique for semiconductor device‐quality silicon and its associated compounds. The vibrational bands in silicon result from phonon absorption and impurities such as oxygen (O
2
), nitrogen (N
2
) and carbon (C). Information relating to the thickness dependence of the phonon bands and the baseline distortions created by free carriers, roughness, and multiple reflections is provided. A discussion of various new and old techniques used to determine the interstitial O
2
, substitutional C and SiO

x

precipitates is presented. Further discussion includes the methods to determine the thickness of epitaxial silicon and SiGe composite layers, and the more recent developments including numerical simulations and concentration profiles of epitaxial layers. A brief review is given for the measurement techniques and calibrations of oxide, doped oxide and nonoxide layer thickness that is crucial to semiconductor device fabrication. The application of photoluminescence (PL) and Raman methods are also briefly discussed.
Structure and Composition of Glasses and Amorphous Materials by Vibrational Spectroscopy
Authors: Cox J. Neal , Armstrong Jeffrey L. 
Published: September 2006

Abstract
The sections in this article are

Rationale for Analysis

Sample Preparation

Silicate Glass

Fluorinated Silicate Glass

Phosphosilicate Glass and Hydroxyl Contaminants

Amorphous Silicon Carbide

Organic and Organo‐Silicate Spin‐On Glasses

Conclusions
Vibrational Spectroscopy of Food and Food Products
Authors: Li‐Chan E.C.Y. , Ismail A.A. , Sedman J. , van de Voort F.R. 
Published: September 2006

AbstractVibrational spectroscopy may be applied to the qualitative and quantitative analysis of complex food systems. Mid infrared (MIR) spectroscopy and Raman spectroscopy are valuable tools for identification and structural characterization of food components and for elucidating structure–function relation of food biopolymers such as proteins. Fourier transform infrared(FT‐IR) spectrometers and chemometrics have broadened the scope of MIR spectroscopy for quality control analysis, but such applications remain generally limited to homogeneous fluid products such as beverages, juices, fats, and oils. In contrast, near infrared (NIR) and FT‐NIR spectroscopy in conjunction with multivariate calibration techniques is becoming increasingly popular in the food industry for rapid and routine analysis of proximate composition of various foods as well as for authentication and detection of adulteration. Increasing application of Raman spectroscopy in food analysis is expected with recent developments in NIR‐FT Raman spectrometers, fibre optic sampling, and confocal Raman microscopy.
Applications of Vibrational Spectroscopy in Brewing
Authors: Meurens Marc , Yan Shou He 
Published: September 2006

AbstractThe purpose of this chapter is to compile the literature concerning the applications of near‐infrared (NIR), mid‐infrared and Raman spectroscopy in the brewing industry. All these three techniques share the advantages that they are rapid, can be noninvasive and allow direct observation of specific molecular species. As for barley, many researchers have used the NIR reflectance on whole grains in malt evaluation. The NIR determination of α/β‐acids and hop storage index in baled hop samples is reported. NIR spectrophotometric methods have been developed for the determination of yeast concentration and activity in beer making. In addition to the applications in the laboratory of quality control, the overview concerns also the applications of infrared and Raman spectroscopy in monitoring of operation and process control at the essential steps of mashing and wort fermentation in brewery. The results obtained with a short wave NIR spectrophotometer are presented in comparison with long wave NIR spectrophotometers.