bluuebunny/crossref_metadata_2025_split huggingface dataset:
A long and winding road: defining the biological role and clinical importance of paraoxonases
Authors: James Richard W. 
Published: September 2006

AbstractParaoxonase-1 (PON1) is an enzyme belonging to a three-member gene family, each of which is highly conserved in mammalian evolution. Whilst there is consensus that the paraoxonase family members have a general protective influence, their precise biological role has remained elusive. A toxicological role, protecting from environmental poisoning by organophosphate derivatives, drove much of the earlier work on the enzymes. More recently, clinical interest has focused on a protective role in vascular disease via a hypothesised impact on lipoprotein lipid oxidation. Recent confirmation that the primary activity of the paraoxonases is that of a lactonase considerably expands the potential sources of biological substrates for the enzyme. Studies on such substrates may shed further light on different mechanisms by which paraoxonases beneficially influence atherosclerosis, as well as defining possible roles in limiting bacterial infection and in innate immunity.Clin Chem Lab Med 2006;44:1052–9.
Flow Friction Fire History and Research
Authors: Gallus TD , Stoltzfus JM 
Published: September 2006

Abstract
Fires in oxygen systems are most commonly attributed to flow dynamic ignition mechanisms such as particle impact and rapid pressurization heating. However, there have been fires in oxygen systems that could not be attributed to the most common ignition mechanisms. Some of these fires have been attributed to a poorly understood ignition mechanism for polymers, called “flow friction.” A brief history of fires attributed to flow friction is presented. In addition, the flow friction research that has been performed at NASA Johnson Space Center White Sands Test Facility is reviewed. Specifically, the possibility that flow friction is simple frictional heating powered by spontaneous gas-driven polymer oscillations is investigated. The results of the latest research on polymer fires based on spontaneous combustion assisted by frictional heat are presented.
Introduction to Vibrational Spectroscopy
Authors: Griffiths Peter R. 
Published: September 2006

Abstract
A brief introduction to the theory of vibrational spectroscopy is given in this chapter. Molecular vibrations are first described in terms of the harmonic oscillator. The Morse potential energy diagram and the concept of anharmonicity are then introduced. The way in which Raman spectra are generated is described in the third section of the article. The factors governing band intensities in infrared and Raman spectra are discussed. In the next section, vibration–rotation spectra of gases are introduced. Then the factors governing the shapes and widths of lines in vapor–phase and condensed‐phase spectra are discussed. In the section on quantitative considerations, Beer's law is described and parameters such as absorptivity, linear absorption coefficient and the optical constants, refractive index, and index of absorption are defined. Finally, a brief introduction to the polarization of radiation is given.
Bandwidths
Authors: Turner James J. 
Published: September 2006

Abstract
The shapes of vibrational bands in solution can provide detailed information about the dynamics of the system. The band shape and the dynamics are related by the Fourier transform relation between frequency and time. The shape is dependent on whether the band is homogeneously or inhomogeneously broadened. Modern vibrational “echo” experiments can distinguish between the two. Most theories of band broadening assume homogeneous broadening. Various dephasing mechanisms contribute to the homogeneous band shape, and the “echo” experiments can unravel – with some surprising results – these contributions. Under appropriate circumstances, dynamic nuclear magnetic resonance (NMR) can provide detailed information about the rate of chemical exchange processes on a “slow” timescale. Under more restrictive conditions, the change in vibrational band shape with temperature can provide the same information but on a “very fast” timescale.
Mid‐Infrared Spectroscopy of the Condensed Phase
Authors: Chalmers John M. 
Published: September 2006

Abstract
This cle introduces some of the main issues that affect the mid‐infrared study of condensed phase samples. It serves as a brief introduction to many of the articles on mid‐infrared spectroscopy that follow in this Handbook. A brief discussion is given of the differences between condensed‐phase (liquid and solid) and gas‐phase absorption band shapes. In the liquid‐state, with some compounds tautomerism can occur such that there is an equilibrium between two or more structural isomers, each of which will have a distinctive spectrum. Many compounds (organic, inorganic, polymeric) are polymorphic, that is they may crystallize into two or more different form. As a consequence of different packing in the crystals each form will have a unique mid‐infrared spectrum, although in some instance the distinctions may only be slight. Mid‐infrared spectroscopy is perhaps the foremost informative technique for studying hydrogen bonding. Enantiomers have indistinguishable mid‐infrared spectra, unless interrogated by the special technique of vibrational circular dichroism (VCD). Many solid materials contain water, either as an integral part of a structure or absorbed within such as a thermoplastic polymer; examples are given of different absorption band profiles in two inorganic systems. Crystal field and factor group splitting of fundamental bands pertaining to crystal structures is discussed, as is the spectra of the disordered state and the influence of defect‐induced structures and spectral changes that occur during the transition in solids from the crystalline through the glassy to the amorphous state. The influences that a sample's bulk physical form and its physical environment may impose on a mid‐infrared spectrum are also introduced. The effects of temperature, pressure, stress and strain on bandwidths and position are briefly considered. For powders, particle size and packing density influences are outlined; the effects of polished and matte surfaces are discussed. For samples such as oriented polymer film or birefringent crystal, alignment of the sample axes with respect to the geometric axes of the spectrometer may have an effect on the relative intensities of bands observed in the recorded spectrum. Their anisotropy may be probed using linearly polarized infrared radiation. Continuous, non‐scattering samples that are uniformly thick may induce multiple passing of the infrared beam within the sample, such that superimposed on a transmission spectrum of the sample one will observe a sinusoidal interference fringe pattern.
Raman Spectroscopy of Gases
Authors: Weber Alfons 
Published: September 2006

AbstractThe sections in this article areIntroductionSpontaneousRaman SpectroscopyHigh‐Resolution Rotation–Vibration SpectraUse of InterferometersRaman Line WidthsIntensity AlternationSupersonic Jet ExpansionsVibrationalRaman SpectraScattering Cross‐SectionsResonanceRaman SpectraRaman Spectroscopy under Extreme ConditionsNonlinearRaman SpectroscopyCoherent Anti‐StokesRaman ScatteringStimulatedRaman Gain or Loss SpectroscopyPhotoacousticRaman ScatteringDouble Resonance TechniquesLine Widths and Line ShapesTime‐Domain Nonlinear SpectroscopyWavenumber Calibration ofRaman SpectraSome ApplicationsSummaryAcknowledgments
Near‐Infrared Spectroscopy of Synthetic and Industrial Samples
Authors: Miller Charles E. 
Published: September 2006

AbstractThe sections in this article areIntroductionHydrocarbonsSaturated HydrocarbonsUnsaturated HydrocarbonsAromatic HydrocarbonsHydrocarbon PolymersSample State Effects – HydrocarbonsKetones, Esters, Ethers, and PeroxidesPolymers with Ketone, Ester, and Ether GroupsSample State Effects – Ketones, Esters, Ethers, and PeroxidesAlcohols and Organic AcidsSample State Effects – Alcohols and Organic AcidsOH‐Containing PolymersNitrogen‐Containing CompoundsSample State Effects – Nitrogen‐Containing CompoundsHalogenated CompoundsAqueous SystemsInorganic MaterialsGasesAcknowledgments
Near‐Infrared Spectroscopy of Biomaterials
Authors: McClure W. Fred , Stanfield Donald L. 
Published: September 2006

Abstract
The sections in this article are

Introduction

Historical Perspective

Biological Samples

Qualitative

NIR

Spectroscopy

Fundamental Components

Water, Oil, Protein and Starch

Water

Oil

Protein

Starch

Plant Materials

Grains

Wheat and Wheat Components

Other Grains

Tea

Coffee

Tobacco

Food and Drink

Food

Cereals

Meats, Poultry and Fish

Fresh Fruit

Additives: Molasses, Honey, Corn Syrup and Lemon Extract

Sweets: Sucrose, Saccharin, Extra and Chocolate

Drink

Milk and Water

Ethanol–Water Mixtures

Spirits

Fiber

Cotton, Flax and Wool

Human Samples

Skin

Hair

Blood

Urine

Future Trends in

NIR

Spectroscopy

Hyphenated Systems

Imaging Spectrometry and Remote Sensing

Hand‐Held Spectrometry

Dedication
Resolution and Instrument Line Shape Function
Authors: Griffiths Peter R. 
Published: September 2006

Abstract

The factors that determine the resolution of monochromators operating in both the non‐diffraction‐limited and diffraction‐limited modes are discussed. The instrument line shape function of a monochromator (often called the spectral slit function) operating above the diffraction limit is a triangle, whereas in the diffraction‐limited case it is sinc
2
([sin
x
]
2
/

x
2

) function. For Fourier transform infrared (FT‐IR) spectrometers, the instrument line shape function is a sinc ([sin
x
]/
x
) function unless the interferogram is multiplied by an apodization function. In this case, the instrument line shape function is the Fourier transform of the apodization function. Common apodization functions that are discussed include the triangular function and the three Norton–Beer functions. The effect of a diverging (noncollimated) beam, passing through the interferometer of a FT‐IR spectrometer, on the resolution and instrument line shape function is discussed at the end of the article.
Optical Constants
Authors: Bertie John E. 
Published: September 2006

Abstract
This article starts with the definition of the optical constants, which are the real and imaginary refractive indices, and is largely concerned with liquid samples. It discusses the behavior of optical constants with changing wavenumber, how they may be measured for isotropic materials like liquids, and their relation to other measures of absorption intensity that are more familiar to chemists and to the real and imaginary dielectric constants which are familiar to physicists. The article describes the use of optical constants in the spectroscopy of liquids, and the relation of optical constant spectra to spectra of other intensity quantities. Finally, the article describes the use of optical constants to obtain molecular properties and absolute integrated absorption intensities for liquid samples and shows how their use greatly facilitates the comparison of the intensities of liquids with those of the same compound in the gas phase.
Infrared Filtometers
Authors: Wilks Paul 
Published: September 2006

Abstract
An infrared filtometer is a selective‐wavelength infrared analyzer which uses narrow band pass optical filters or a linear variable filter to isolate specific wavelengths in the near or mid infrared spectral regions. Infrared filtometers are generally small, portable, operable in the field or in line in the processing plant. Many hundred fixed filter instruments are in use for oil‐in‐water analysis on oil platforms and for effluent water in chemical plants and municipalities. Variable wavelength filtometers monitor ambient air and food properties such as trans fat and alcohol in wine and carbonation and sugar levels in beverages. Recently, filter‐based infrared monitors have been developed for medical diagnostic procedures.
Because of their simplicity, relatively low cost, and adaptability, infrared filtometers are the fastest growing segment of the infrared analytical market with well over 25,000 units in use worldwide.
Continuous Scanning Interferometers for Mid‐Infrared Spectrometry
Authors: Jackson Richard S. 
Published: September 2006

Abstract
This chapter discusses the continuous scanning interferometers that are used primarily for mid‐infrared spectrometry. The chapter initially lays some groundwork by describing the principles of operation of a Michelson interferometer, including the use of a reference laser to control scanning and data acquisition. The chapter then describes sources of error in interferometers, for example velocity and alignment errors, and the different components of an interferometer, such as mirror assemblies and bearings. These sections also cover how the effects of these errors can be controlled using mechanical, optical, and electronic design. The chapter concludes with a number of examples of interferometer design that exemplify the materials discussed in earlier sections.
Incandescent Sources for Mid‐ and Far‐Infrared Spectrometry
Authors: Buijs Henry 
Published: September 2006

AbstractThe sections in this article areBackgroundÉtenduePower Emitted by an Ideal Incandescent SourceAPractical Mid‐ and Far‐Infrared SourceOther Mid‐ and Far‐Infrared SourcesVery‐Far‐Infrared SpectroscopyHigh Resolution Infrared SpectroscopyIRSpectroscopy with a Synchrotron SourceTerahertz Spectroscopy
Instrumentation for Far‐Infrared Spectroscopy
Authors: Griffiths Peter R. , Homes Christopher C. 
Published: September 2006

Abstract

The various components of far‐infrared spectrometers are discussed in this article. For measurements above 100 cm
−1
, a standard silicon carbide (Globar) source may be used. For longer wavelengths, a high‐pressure mercury lamp is required. When higher radiance is required, synchrotrons emit much higher far‐infrared photon fluxes than either the Globar or the mercury lamp. Pneumatic (Golay) detectors were popular as far‐infrared detectors, as long as the modulation frequency was low. Despite their relatively low sensitivity, pyroelectric bolometers such as the deuterated triglycine sulfate (DTGS) detector are more commonly used because of their better high‐frequency response, which is necessary for Fourier transform infrared (FT‐IR) spectrometry. When very high sensitivity is required, liquid‐helium cooled bolometers are used. Most far‐infrared spectra are measured using an interferometer. In the early days of FT‐IR spectrometry, most interferometers were of the slow continuous‐scan or simple step‐scan variety; lamellar grating interferometers were used for very long‐wavelength measurements. Today, most far‐infrared FT‐IR spectrometers incorporate rapid‐scan interferometers of the same type used for mid‐infrared measurements. A number of special‐purpose instruments are also described, including the Genzel interferometer. All these instruments must be equipped with beamsplitters that are configured for far‐infrared operation. Poly(ethylene terephthalate), also known as Mylar or Melinex, is the most common material used to fabricate far‐infrared beamsplitters but other materials have better efficiency. These include solid silicon or silicon that has been vapor‐deposited onto Mylar.
Diode Laser Spectrometers for Mid‐Infrared Spectroscopy
Authors: Mantz Arlan W. 
Published: September 2006

Abstract
The sections in this article are

Introduction

The Source

The Optical System

Line Intensity and Line Shape Measurements

Tunable Diode Laser Line Shape

Absorption Line Profile

A Brief Summary of Some Novel Applications of Tunable Diode Lasers
Synchrotron and Free Electron Laser Sources of Infrared Radiation
Authors: Williams G.P. 
Published: September 2006

Abstract
In this article, we describe the infrared sources that are based on electron accelerators. Such sources have novel properties that allow them access to unique applications, which are complementary to those with laboratory‐based sources. Specifically, accelerator‐based sources are extremely bright, and are pulsed. Synchrotrons are broadband sources that are up to 1000 times brighter than black body sources and with pulses that are of order 100 ps long. Free electron laser sources are 6–10 orders of magnitude brighter than synchrotron radiation sources, but are narrow band. The pulse lengths are sub‐picosecond. Both sources have pulse repetition frequencies of around 100 MHz. This article explains concepts of brightness and how these sources fit into the menu of available sources for vibrational spectroscopy.
Instrumentation and Methods for High‐Resolution Gas‐Phase Spectroscopy
Authors: McNaughton Don 
Published: September 2006

AbstractThe sections in this article areIntroductionFourier Transform Infrared SpectroscopyOptical ConsiderationsInstrument Line Shape and ResolutionAperture and ResolutionOther Optical ComponentsData HandlingLaser TechniquesCoupling of Equipment to High‐Resolution SpectrometersSignal‐to‐Noise RatioSpectral SimplificationComputer ManipulationSpecialist Techniques and InstrumentsSub‐Doppler SpectroscopyField Instruments
Monochromators for Near‐Infrared Spectroscopy
Authors: DeThomas Frank A. , Brimmer Paul J. 
Published: September 2006

Abstract
The sections in this article are

Introduction

Diffraction Gratings

Monochromator Components

Concave Holographic Gratings

Grating Drive

Sources

Entrance and Exit Slits

Wavelength, Order and Interference Filters

Detection

Design Considerations

Stray Light

Sample Absorptivity

Spectral Resolution

Pre‐Post‐Dispersive Monochromators

Designing with Fiber Optics

Standardization of Spectra

Conclusions
Hadamard Transform Near‐Infrared Spectrometers
Authors: Hammaker Robert M. , DeVerse Richard A. , Asunskis Daniel J. , Fateley William G. 
Published: September 2006

AbstractHadamard transform (HT) spectrometry is introduced using a 3‐resolution element example to illustrate the operation of an HT spectrometer and its multiplex advantage leading to an improved signal‐to‐noise ratio (SNR). The Hadamard encoding mask is described and the digital micro‐mirror array (DMA) is introduced and described to demonstrate that the DMA is an attractive choice for the Hadamard encoding mask.A near‐infrared DMA spectrometer and some of its features are described and its SNR advantage relative to a classical scanning dispersive spectrometer is demonstrated experimentally. The potential for the combination of the DMA with a single‐elementdetector to provide an important advancement in spectroscopic instrumentation is indicated.
Near‐Infrared Array Spectrometers
Authors: Stark Edward W. 
Published: September 2006

AbstractDiode‐array spectrometers have become well established for use in the near‐infrared (NIR) spectral region, particularly with fiber‐optic probes. This article discusses the advantages of array spectrometers, specifically, photometric performance, measurement speed, wavelength resolution, stability and accuracy, environmental ruggedness, and reduced cost. The spectral signal, optical throughput, noise sources, and resolution and the spectral response performance parameters of array spectrometer systems are described.The properties of diffraction grating polychromators are discussed in detail starting with diffraction grating principles, spectral resolution, and throughput. Stray radiant energy, absorbance linearity, and dynamic range are considered. Specific grating related issues, including multiple diffraction orders, grating efficiency, and Wood’s anomalies, are defined. The properties of the concave holographic grating and its unique geometry are described.Array detectors for NIR spectroscopy have different requirements than those for Raman spectroscopy due to the larger optical signal and dynamic range typical of NIR transmittance and reflectance measurements. The principles of photon detectors, the operational theory of photodiodes, particularly InGaAs, and the responsivity of various NIR detectors are reviewed. Resistive and capacitive transimpedance preamplifier circuits are compared, with an emphasis on dynamic range and signal amplitude resolution.Discussion of the sources of visible and NIR array spectroscopy completes the review of the principle elements of an array spectrometer system. The spectral radiance of tungsten‐halogen lamps and its temperature sensitivity are described, as are the halogen cycle and the issues of lamp life and failure modes. Finally, deuterium arc lamps and xenon arc and flash lamps are discussed in brief.
Volume Phase Holographic Optical Elements
Authors: Owen H. 
Published: September 2006

Abstract
The sections in this article are

Introduction

Background

Holographic Materials and Fabrication Process

Film Preparation

Laser Exposure

Chemical Processing

Drying and Sealing

Physical and Optical Properties

Holographic Notch Filters

Background

Operating Characteristics

Optical Characteristics

Polarization Properties

Laser Bandpass Filters

Description

Volume Phase Holographic Gratings

Summary
Continuous Lasers for
R
aman Spectrometry
Authors: Pan Ming‐Wei , Benner Robert E. , Smith Lee M. 
Published: September 2006

Abstract
There are many different factors to consider when determining the appropriate excitation laser source for continuous wave Raman experiments. The laser characteristics of interest for designing a Raman system fall into two categories. The first category includes parameters associated with the laser output, such as wavelength, linewidth, output power, polarization, and beam quality. The second category includes physical characteristics of the laser system, such as size, reliability, and power consumption. The different characteristics of gas, dye, solid‐state, and semiconductor lasers are discussed. Comparisons of individual lasers for Raman applications illustrate some of the tradeoffs associated with the various laser parameters, and also provide an indication of the signal levels that can be expected in continuous wave Raman measurements from different kinds of materials.
Inverse
R
aman Spectrometry
Authors: Bermejo Dionisio 
Published: September 2006

Abstract
The sections in this article are

Introduction

Experimental

Quasi‐

CW

SRS

Spectrometer

Probe Laser

Pump Laser

Data Acquisition and Calibration

Applications

Diatomic Molecules

Nitrogen

Oxygen

Hydrogen and Deuterium

Fluorine and Chlorine

Carbon and Nitrogen Monoxides

Linear Molecules

Carbon Dioxide

Acetylene

Other Linear Molecules

Spherical Top Molecules

Methane

Other Spherical Top Molecules

Symmetric Top Molecules

Asymmetric Top Molecules

Photoacoustic

SRS

Acknowledgements