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Dissolved organic matter (DOM) is the most reactive organic carbon pool in earth. However, the heterogeneity of this organic mixture makes it difficult to investigate its dynamics under different external perturbations. In this review, we present the potential of using the two dimensional correlation spectroscopy analysis (2D correlations) as a tool to study the dynamic of DOM. We demonstrate the application of the 2D correlation analysis on high molecular weight DOM (HMW-DOM) with the salinity as perturbation parameter. We used four different chemical probes: Carbon nuclear magnetic resonance spectroscopy (13C NMR), Fourier transform infrared spectroscopy (FTIR), proton nuclear magnetic resonance spectroscopy (1H NMR) and Fourier transform ion cyclotron resonance mass spectrometry (FTICR-MS).

We present a novel, cavity-enhanced spectroscopic technique based on a phase-matched Raman process to detect trace quantities of gas. The essence of this technique is the careful control of cavity dispersion to satisfy the phase-matching condition of coherent anti-Stokes Raman scattering (CARS) enhanced in a high-finesse optical cavity. A 6000-fold improvement of the CARS signal is observed under optimized conditions, indicating that this is a promising tool to quantify Raman-active molecules with an extremely low detection limit.

Laser-induced breakdown spectroscopy only provides limited information about chemical products in laser-induced plasmas. In this work, time-resolved resonance fluorescence spectroscopy was studied as a promising tool for the study of chemical reactions in laser-induced plasmas.

Extended abstract of a paper presented at Microscopy and Microanalysis 2009 in Richmond, Virginia, USA, July 26 – July 30, 2009

Guest editors Matthew Baker and Karen Faulds introduce the Fundamental Developments in Clinical Infrared and Raman Spectroscopy issue of Chemical Society Reviews

Both atomic force microscopy (AFM) and Raman spectroscopy are techniques used to gather information about the surface properties of a sample. There are many reasons to combine these two technologies, and this article looks both at the complementary information gained from the techniques and how a researcher having access to a combined system can benefit from the additional information available.

Conformation selective: A new technique of ultraviolet-ultraviolet hole burning spectroscopy that can be applied to ions stored in a quadrupole ion trap (QIT) is developed and used to obtain the conformation-selective electronic spectra of dibenzo[18]crown-6 complexes with alkali metal cations (M(+), see picture; F(+) = fragment).

The composition and molecular structure of preceramic nanozirconooligocarbosilanes have been determined using a variety of physicochemical characterization techniques: nuclear magnetic resonance (1H, 29Si, 13C), IR spectroscopy, transmission electron microscopy, gel-permeation chromatography, scanning electron microscopy, thermogravimetry, X-ray photoelectron spectroscopy, and elemental analysis.

Recent developments in analytical instrumentation have led to revolutionary discoveries in cosmochemistry. Instrumental advances have been made along two lines: ( i ) increase in spatial resolution and sensitivity of detection, allowing for the study of increasingly smaller samples, and ( ii ) increase in the precision of isotopic analysis that allows more precise dating, the study of isotopic heterogeneity in the Solar System, and other studies. A variety of instrumental techniques are discussed, and important examples of discoveries are listed. Instrumental techniques and instruments include the ion microprobe, laser ablation gas MS, Auger EM, resonance ionization MS, accelerator MS, transmission EM, focused ion-beam microscopy, atom probe tomography, X-ray absorption near-edge structure/electron loss near-edge spectroscopy, Raman microprobe, NMR spectroscopy, and inductively coupled plasma MS.

In-source resonance ionization spectroscopy of uranium has been carried out as preparation for the analysis of low contaminations of nuclear material in environmental samples via laser mass spectrometry. Using three-step resonance ionization spectroscopy, 86 levels of odd parity in the energy range from 37,200–38,650 cm − 1 were studied, 51 of these levels were previously unknown. Suitable excitation schemes for analytic applications are discussed.

Different techniques are used for the sensitive detection of overtone transitions of small molecules, such as H 2 S, C 2 H 2 , OCS, O 3 in the visible and near infrared region. The techniques include: phase-modulated or wavelength-modulation absorption spectroscopy with a widely tunable single mode diode laser, opto-acoustic spectroscopy in resonance cells with a color center laser or a Ti:Sapphire laser, and sub-Doppler opto-thermal spectroscopy in cold collimated molecular beams, using a low temperature bolometer as detector. The three techniques are compared with regard to sensitivity and spectral resolution. The mass selective sensitive detection of small metal clusters Li 3 and Na 3 and their high resolution sub-Doppler spectroscopy, using resonant two-photon ionization with cw lasers, is briefly discussed.

New synthetic routes to 1-methyl-1-silaindane (1b) and 1-methyl-1-germaindane (1b) were developed and the desired products were obtained in good isolated yield. Compounds 1a and 1b were fully characterized by mass spectroscopy, 1H and 13C{1H} NMR, and infrared spectroscopy.

Optical-optical double-resonance spectroscopy with a CW pump laser and dual-comb technique were demonstrated. We obtained the fully resolved hyperfine spectra of rubidium, and the absolute frequencies of the spectra were determined precisely.

This article examines the utility of atomic absorption spectroscopy, in conjunction with cold flux assays, to ion channel screening. The multiplicity of ion channels that can be interrogated using cold flux assays and atomic absorption spectroscopy is summarized. The importance of atomic absorption spectroscopy as a screening tool is further elaborated upon by providing examples of the relevance of ion channels to various physiological processes and targeted diseases.

Atomic absorption spectroscopy is one of the important instrumental techniques for both quantitative and qualitative analysis of metallic and nonmetallic elements in inorganic or organic materials....

Optical emission spectroscopy and Langmuir probe measurements have been performed under varying conditions, close to those previously optimized for high-pressure on-axis DC sputter deposition of Y Ba2Cu3O7−x (Y123) films. The electron temperature and density of the plasma were mapped between the target and substrate. The aim of the investigation was to discern the effect of small variations of plasma environment on film growth and thus to enable precise tuning of the deposition conditions for Y123 and Y Ba2Cu4O8 (Y124) films for different applications. The input parameters varied were: Ar-to-O2 ratio in the sputtering gas and small additions of He, H2 or H2O; total pressure; target composition (Y123 or Y124); and deposition temperature Ts. The films were characterized by four-point and inductive Tc measurements, x-ray diffractometry, Raman spectroscopy, Auger electron spectroscopy, Rutherford back scattering, x-ray photoelectron spectroscopy, atomic force microscopy, scanning electron microscopy, and x-ray energy dispersive spectrometry. A model has been developed to account for the structural peculiarities observed in the x-ray diffractograms of hydrogen-loaded Y123 films deposited in O2/Ar+H2O presented.

The growth of the polycyclic aromatic hydrocarbon perylene on (110) oriented copper substrates has been studied by means of x-ray photoelectron spectroscopy, near-edge x-ray absorption spectroscopy, and atomic force microscopy. In the monolayer regime, the molecules are orientated with their molecular plane parallel to the substrate, whereas they adopt a tilted arrangement in multilayer films. For multilayers with thicknesses exceeding 10 nm, the molecules grow in a bulk-like structure with their long axes orientated upright to the substrate surface.

IR spectroscopic techniques to study isolated biomolecules.- Cryogenic methods for the spectroscopy of large, biomolecular ions.- Theoretical Methods for vibrational spectroscopy and collision induced dissociation in the gas phase.- Peptide fragmentation products in mass spectrometry probed by infrared spectroscopy.- Spectroscopy of Metal-Ion Complexes with Peptide-Related Ligands.- Isolated neutral peptides.- Gas-phase IR Spectroscopy of Nucleobases.- Carbohydrates.- Microwave spectroscopy of biomolecular building blocks.

The methods for the determination of various types of oxygen surface functions on carbon materials are briefly described, and their relative advantages and problems that may arise are discussed. Acidimetric titration techniques, IR spectroscopy, XPS, thermal desorption spectroscopy, and electrokinetic measurements are described.

Electrophoretic technology is used to purify BC3.3N in an amorphous carbon and hexagonal boron nitride sample. The results are acquired using Raman spectroscopy and field emission scanning electron microcopy with energy dispersive spectroscopy, which show that pure BC3.3N is obtained from graphite and hexagonal boron nitride. The structural characteristics of this compound are studied by Fourier transform infrared spectroscopy. A simple method for purifying B-C-N compounds is presented.

The chemical structures of various ion-beam irradiated isotactic-polypropylene samples were studied. Results of micro-Fourier transform infrared spectroscopy and ultraviolet–visible spectroscopy suggest not only the linear energy transfer, but also the fluence is effective in local transformation of the isotactic-polypropylene.

It was previously reported (R. Mills et al., Synthesis and characterization of potassium iodo hydride, Int. J. Hydrogen Energy, 25(12) (2000) 1185) that a novel inorganic hydride compound KHI which comprised a high binding energy hydride ion was synthesized by reaction of atomic hydrogen with potassium metal and potassium iodide. Potassium iodo hydride was identified by time of flight secondary ion mass spectroscopy, X-ray photoelectron spectroscopy, 1H and 39K nuclear magnetic resonance spectroscopy, Fourier transform infrared spectroscopy, electrospray ionization time of flight mass spectroscopy, liquid chromatography/mass spectroscopy, thermal decomposition with analysis by gas chromatography, and mass spectroscopy, and elemental analysis. We report measurements of heats of formation of KHI by differential scanning calorimetry (DSC) on a very reliable commercial instrument, a Setaram HT 1000 calorimeter. With reactant KI present, potassium metal catalyst and atomic hydrogen were produced by decomposition of KH at an extremely slow rate under a helium atmosphere to increase the amount of atomic hydrogen by slowing the rate of molecular hydrogen formation. Since not all of the starting materials reacted, the observed minimum heats of formation were over compared to the enthalpy of combustion of hydrogen of .

The atomic scale oxidation of the alpha-SiC(0001)-(3 x 3) surface is investigated by atom-resolved scanning tunneling microscopy, core level synchrotron radiation based photoemission spectroscopy, and infrared absorption spectroscopy. The results reveal that the initial oxidation takes place through the relaxation of lower layers, away from the surface dangling bond, in sharp contrast to silicon oxidation.