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Abstract Silicon nitride (Si 3 N 4) powders were subjected to amination modification by grafting γ-aminopropyltriethoxysilane (APTES) via a direct blending method in solution. Fourier transform infrared (FTIR) and X-ray photoelectron spectroscopy (XPS) analyses indicated that the hydroxyl groups present on the surface of Si 3 N 4 powder particles interacted with the silanols groups of APTES to combine through covalent bonding. Thermogravimetric analysis (TGA) suggested that the grafting of APTES on Si 3 N 4 powder surface was successful with grafting content reaching up to 7%. Compared to native Si 3 N 4 , the surface hydrophilicity of amino Si 3 N 4 powder was enhanced and dispersibility was improved. Overall, these findings indicated the promising aspects of amination modification and future potential use in environmental protection by using water instead of organic solvents during Si 3 N 4 ceramic formation process. [ABSTRACT FROM AUTHOR]

Abstract We present novel results on the free base 5,10,15,20-meso-tetra(pyridyl)-21H,23H-porphyrin (H 2 TPyP). This molecule presents complex electronic and vibrational properties and despite the vast literature reporting the transitions observed in its absorption and fluorescence spectra, a more accurate interpretation has been kept elusive. In particular, we show that the molecule's Q -band develops into many electronic and vibronic transitions, whose the well-known "four orbital model" finds it difficult to reconcile. Using distinct spectroscopy techniques, we conclude that both Q x - and Q y -bands comprise, in fact, two quasi-degenerated electronic states together with their respective vibronic progressions each. The analysis of the Huang-Rhys factors and complementary time- and polarization-resolved measurements reinforce the need for the proposed Q -band multi features remodeling. Graphical Abstract Unlabelled Image Highlights • The asymmetric shape of Q y and Q x absorption bands of H 2 TPyP is discussed. • Q -band is composed of multi-electronic transitions. • Spectral derivative and deconvolution support remodeling of current description. • The vibrational modes belonging to vibronic progressions are determined. [ABSTRACT FROM AUTHOR]

Abstract The velocity–vorticity formulation of the 3D Navier–Stokes equations was recently found to give excellent numerical results for flows with strong rotation. In this work, we propose a new regularization of the 3D Navier–Stokes equations, which we call the 3D velocity–vorticity-Voigt (VVV) model, with a Voigt regularization term added to momentum equation in velocity–vorticity form, but with no regularizing term in the vorticity equation. We prove global well-posedness and regularity of this model under periodic boundary conditions. We prove convergence of the model's velocity and vorticity to their counterparts in the 3D Navier–Stokes equations as the Voigt modeling parameter tends to zero. We prove that the curl of the model's velocity converges to the model vorticity (which is solved for directly), as the Voigt modeling parameter tends to zero. Finally, we provide a criterion for finite-time blow-up of the 3D Navier–Stokes equations based on this inviscid regularization. [ABSTRACT FROM AUTHOR]

While the Voigt function is recognized as the best function to represent the photoelectron spectroscopic process, it is less frequently used because it cannot be represented as an analytical function and thus has to be evaluated numerically. This paper shows how the true Voigt function can be calculated rapidly with approximately the same speed as pseudo‐Voigt functions by using approaches that have been used by the astronomical sciences community. The Voigt function is calculated using code previously published by Wells. The paper describes a method for calculating the function to generate photoelectron peaks for curve fitting X‐ray photoelectron spectroscopic data. An appendix is provided with the listing of a Fortran 90 program which uses the subroutine HUMDEV published by Wells. Examples of using this approach for the fitting of experimental core X‐ray photoelectron spectroscopic data are presented, and the fits compared with fits using a pseudo Voigt product function. The use of the true Voigt function in the calculation of spectra in the core and valence band region is also described and illustrated by comparing the calculated spectra with experimental spectra. [ABSTRACT FROM AUTHOR]

Highlights • A very accurate variant of trapezoidal integration with residue correction scheme is indicated. • Numerical oscillations are reduced by symmetrising the nodes around the real part of the poles. • About a hundred quadrature nodes and a single residue term guarantees 30 digit accuracy. • Arbitrary accuracy can be realised. • This is done by increasing the range of integration and by reducing the step-size for the Voigt functions. Abstract Here we indicate how a particular version of the trapezoidal integration with residue correction for the evaluation of the Voigt functions indicated by us previously can be easily extended to serve the purpose of reference value generation. Specifically by resorting to quadruple precision, we demonstrate a reliable computation with a minimum of 30 digit accuracy for the Voigt functions H (x, a) and G (x, a). Compared to the prescription of Boyer et al., this method reduces the computational cost several fold when very high reference accuracy is the aim. In addition we show that when both the parameters x and a are less than unity, the series of Faddeeva et al. can be profitably used for the required evaluation instead of this quadrature. [ABSTRACT FROM AUTHOR]

Highlights • Linestrengths and temperature-dependent lineshape self-parameters were measured for 8 CO 2 transitions near 1.43 µm from 300 to 1000 K. • Voigt, Rautian, Galatry and speed-dependent Voigt profiles are used to recover the absorbance and obtain self-spectroscopic parameters for CO 2. • The self-Dicke narrowing coefficients and self-speed-dependent coefficients were measured to account for the Dicke narrowing and speed-dependent effects in pure CO 2. • The 8 transitions exhibited linestrengths and self-broadening and narrowing coefficients that decreased with increasing temperature. Abstract Linestrengths, self-broadening and narrowing coefficients for 8 absorption transitions of CO 2 near 1.43 µm were measured using the wavelength modulation direct absorption spectroscopy (WM-DAS) at 300–1000 K and 5–20 kPa. The SNR was enhanced to 1500 for the peak absorbance around 5% at room temperature and remains at 550 for the peak absorbance around 1% at high temperatures by use of the WM-DAS method. The Voigt, Rautian, Galatry and quadratic speed-dependent Voigt profiles were used to recover the absorbance and retrieve the best-fit spectroscopic parameters and their temperature dependence. The quadratic speed-dependent Voigt profile was found to give the best combination of accuracy and robust lineshape parameters. The measured linestrengths and self-broadening coefficients compare well with the available values listed in the HITRAN/HITEMP database. The self-narrowing coefficients were also determined for GP, RP and qSDVP with analyses of the uncertainties in these spectroscopic parameters. [ABSTRACT FROM AUTHOR]

Highlights • An efficient Sinc function based numerical integration is indicated. • This method involves Trapezoidal integration with corrections for residues. • Numerical oscillations are reduced by symmetrising the nodes around the real part of the poles. • A satisfactory Saddle point estimation of the Discretisation Error is provided. • This method provided reference values for both the ordinary and the generalized Voigt functions. Abstract For the ordinary and the generalised Voigt functions, we indicate an accurate and efficient sinc function based numerical integration method. This involves a trapezoidal integration with residue correction for the poles of the integrand. We provide a rough saddle point estimate of the discretisation error. We also indicate how to reduce the numerical oscillations by symmetrising the quadrature nodes around the real part of the singularity. By a suitable step size choice, a minimum of 14 digit accuracy (with respect to published reference values) is guaranteed for the generalised Voigt function evaluation for all values of the dependent parameters. [ABSTRACT FROM AUTHOR]

Abstract Gas line shape is determined by the Voigt profile, which is the convolution of Lorentz and Doppler profiles. The calculation amount in the Voigt profile is much larger than that in the two other profiles, and an approximate Lorentz or Doppler profile is generally used in gas concentration detection via tunable laser absorption spectroscopy. The normalized peak ratio and error function are introduced to compare the approximating effect of the two profiles. The normalized peak ratio value is simulated for Doppler profile and Lorentz profiles over a variable temperature and pressure, respectively. The 10%, 5% and 2.5% error functions for pressure versus temperature are obtained for the two profiles. Oxygen at a wavelength of 760 nm is used to demonstrate the simulation results. The presented method of investigating line shapes can be applied to other gas spectrum lines. [ABSTRACT FROM AUTHOR]

In the present paper we establish the existence of weak solutions to one fractional Voigt type model of viscoelastic fluid. This model takes into account a memory along the motion trajectories. The investigation is based on the theory of regular Lagrangean flows, approximation of the problem under consideration by a sequence of regularized Navier-Stokes systems and the following passage to the limit. [ABSTRACT FROM AUTHOR]

Line shift and broadening rates have been measured for three v’ j’ levels of the X→A manifold in Li2 with Xe as perturber gas. The lines are shifted and asymmetrically broadened and have been fitted using a speed dependent Voigt function that correlates the effect of velocity and broadening and shift rates. This asymmetric speed dependent Voigt profile (ASDVP) permits resolution of both effects at low foreign gas pressures, thus a shift corresponding to 11 MHz at line center was measured at 10 Torr xenon. Results are presented for the levels (v’,j’) 18,6; 20,20; 32,15 of A 1Σ+u and a reduction of shift and broadening rates is observed as j’ increases. This is attributed to the effective anisotropic contribution as rotor speed increases. [ABSTRACT FROM AUTHOR]

The Voigt profile is important for spectroscopy, astrophysics, and many other fields of physics, but is notoriously difficult to compute. McLean et al. [1] [J. Electron Spectrosc. & Relat. Phenom., 1994] have proposed an approximation using a sum of Lorentzians. Our assessment indicates that this algorithm has significant errors for small arguments. After a brief survey of the requirements for spectroscopy we give a short list of both efficient and accurate codes and recommend implementations based on rational approximations. [ABSTRACT FROM AUTHOR]

In this computational study, the nanoscale mechanical properties of C-S-H composite materials under different temperatures are evaluated with molecular dynamics (MD). The effects of different proportions of crystals, levels of porosity, and degrees of temperature on the nanoscale mechanical properties of the C-S-H composites are investigated. The initial computational models are built up based on tobermorite and jennite crystals, and the geometries of the models are then optimized before performing MD simulations at 25 °C, 80 °C, and 200–1500 °C with the interval of 100 °C, respectively. The resulting mechanical properties of the composites are evaluated under different conditions. The self-consistent (SC), Mori-Tanaka (MT), and Voigt methods are used to understand the effects of crystal proportions and porosities on the mechanical properties of the C-S-H composites at three representative temperatures. It is found that both the bulk and shear moduli of the C-S-H composites are decreased with the increasing temperature. Regarding the influence of porosity, a specific proportional relationship is obtained based on the results with the SC, MT, and Voigt methods. The reported findings provide a better insight into the thermomechanical response of the C-S-H composites. [ABSTRACT FROM AUTHOR]

We report the results of a computational investigation of two blow-up criteria for the 3D incompressible Euler equations. One criterion was proven in a previous work, and a related criterion is proved here. These criteria are based on an inviscid regularization of the Euler equations known as the 3D Euler-Voigt equations, which are known to be globally well-posed. Moreover, simulations of the 3D Euler-Voigt equations also require less resolution than simulations of the 3D Euler equations for fixed values of the regularization parameter $$\alpha >0$$ . Therefore, the new blow-up criteria allow one to gain information about possible singularity formation in the 3D Euler equations indirectly, namely by simulating the better-behaved 3D Euler-Voigt equations. The new criteria are only known to be sufficient criterion for blow-up. Therefore, to test the robustness of the inviscid-regularization approach, we also investigate analogous criteria for blow-up of the 1D Burgers equation, where blow-up is well known to occur. [ABSTRACT FROM AUTHOR]

We have studied the surface electronic structure of AV 10 O 15 (A = Ba, Sr) and Ba 0.9 Sr 0.1 V 13 O 18 by using x-ray photoemission spectroscopy (XPS). The V 2 p XPS shows multiple peaks associated with the charge fluctuation in the system. The relative intensity of each valence component can be extracted by Gaussian and Voigt fittings. The result strongly depends on the number of Gaussians/Voigts. In BaV 10 O 15 and Ba 0.9 Sr 0.1 V 13 O 18, the surface state has more V 3+ than the bulk. In addition to the presence of surface V 3+ , the V 2.5+ in AV 10 O 15 (A = Ba, Sr) and V 2+ in Ba 0.9 Sr 0.1 V 13 O 18 systems are observed even in the surface sensitive XPS. The number of Gaussians/Voigts should be as large as four for the V 2 p 3/2 , in order to obtain the results consistent with the bulk sensitive HAXPES study. [ABSTRACT FROM AUTHOR]

The chemical shift in Kα and Kβ 1,3 X-ray emission lines of 47 Ag, 48 Cd and 50 Sn compounds have been studied by using highly equipped advanced S8 TIGER WDXRF spectrometer. From the results, it is found that halogen compounds are more sensitive for chemical shifts than other compounds. With change of transition probabilities and outermost shell energy levels, chemical shift measured in Kβ 1,3 X-ray emission lines are observed more than that of Kα emission lines. It is also found that chemical shift (ΔE) and effective charge (q) are increased with increasing number of ligands attached to the central metal atom. To show the dependency behaviour of chemical shift and effective charge with each other, we establish a linear relation between them in different 48 Cd and 50 Sn compounds. [ABSTRACT FROM AUTHOR]

Approximately seventy isolated and overlapping methane absorption lines in the 5647 − 6164 cm −1 spectral region were processed with seven line profiles accounting for all main line shape forming physical mechanisms in different combinations. It was shown that at low methane pressures the conventional Nelkin–Ghatak line profile gives satisfactory results in retrieving line parameters as opposed to the Voigt profile. It was found that most of the considered lines do not interfere. The FTS instrumental function elimination technique based on Doppler-broadened line's records was applied, and its applicability was proved. [ABSTRACT FROM AUTHOR]

A simple, closed-form expression for the step response or pulse shape of a magnetic recording channel is described. The step responses of inductive and magnetoresistive heads with thin-film media are shown to be well approximated by a Voigt function (the convolution of a Lorentzian and a Gaussian function). For convenience, an accurate approximation to the Voigt function (the linear superposition of a Lorentzian and a Gaussian function with appropriate weighting) was fit to the step responses using one adjustable parameter. The improved accuracy of this approximation to the step response has a strong impact on channel performance analysis and modeling. © 2000 American Institute of Physics. [ABSTRACT FROM AUTHOR]

New possibilities of using the Voigt profile are suggested for investigation of characteristics of radiation absorption in a gas. For this purpose, the absorption coefficient in the line center and the total absorption linewidth are determined without knowledge of a dependence of the shape of the Voigt profile on the frequency. Asymptotic values of these characteristics are determined. Based on this approach, the temperature of ions in ultracold plasma is determined and compared with the available experimental data. [ABSTRACT FROM AUTHOR]

Transition-metal-catalyzed electrophilic amination has been developed into a powerful tool for C−N bond construction. So far, O-benzoylhydroxylamines are the most widely used electrophilic aminating reagents. Herein, we summarize the recent advances of O-benzoylhydroxylamines involved in electrophilic amination catalyzed by transition metals. Several pioneering studies and some of the relevant mechanisms are discussed in this review. [ABSTRACT FROM AUTHOR]

Herein we disclose a novel method for the facile transfer of primary (-NH2) and secondary amino groups (-NHR) to heteroaryl- as well as arylcuprates at low temperature without the need for precious metal catalysts, ligands, excess reagents, protecting and/or directing groups. This one-pot transformation allows unprecedented functional group tolerance and it is well-suited for the amination of electron-rich, electron-deficient as well as structurally complex (hetero)arylmetals. In some of the cases, only catalytic amounts of a copper(I) salt is required. [ABSTRACT FROM AUTHOR]

A method for quantitative X-ray diffraction analysis is developed for direct determination of the glassy phase content of fly ash in a hydrating binary blend of cement and low-calcium, siliceous fly ash. The intensity contributions of the unhydrated glassy phase of fly ash and the amorphous reaction products to the intensity pattern of the total amorphous phase in the hydrating binary blend are obtained by decomposition of the total intensity signature as a sum of component pseudo Voigt ( PV) peaks. An experimental program involving binary blends with three different low calcium siliceous fly ashes and two different curing temperatures is reported. The centers of the component PV peaks of the fly ash glassy phase fitted to the overall intensity pattern are found to be invariant. The glassy phase content of hydrating binary blends determined from the XRD method were found to agree well with the values obtained from a selective dissolution method. [ABSTRACT FROM AUTHOR]

Presents a study which observed the magneto microwave Kerr effect in the Voigt configuration on polycrystalline magnesium-manganese ferrite samples at x-band frequency. Background on the magneto microwave Kerr effect; Computational approach; Results and discussion.

The first example of intermolecular amination of unactivated C(sp3)−H bonds by cyclic alkylamines mediated by Cu(OAc)2/O2 is reported. This method avoids the use of benzoyloxyamines as the aminating reagent, which are normally prepared from alkylamines in extra steps. A variety of unnatural β2, 2-amino acid analogues are synthesized by this simple and efficient procedure. This approach offers a solution to the previous unmet challenge of C(sp3)−H/N−H activation for the formation of C(sp3)−N bonds. [ABSTRACT FROM AUTHOR]

This article studies the stabilization of the explicit time stepping methods for Hall Maxwell and incompressible Hall MHD equations. Since the Hall effect term contains two spatial derivatives, classical time-stepping schemes result in very restrictive CFL condition. We consider weakening the restrictive time step condition via Voigt regularization. We establish the energy stability result and validate our approach numerically. Numerical experiments demonstrate that we are able to take larger time steps, compared to classical schemes, at additional, negligible computational cost. [ABSTRACT FROM AUTHOR]

The paper presents results of studies on the crystallite sizes of oxide layer formed during a long-term operation on steel at an elevated temperature. This value was determined by a method based on analysis of the diffraction line profile, according to a Scherrer formula. The oxide layer was studied on a surface and a cross-section at the inner site on the pipe inlet, at the fire and counter-fire wall of the tube. X-ray studies were carried out on the inner surface of a tube (in a flowing medium environment), then the layer's surface was polished and the diffraction measurements repeated to reveal differences in the originated oxides layer. X-ray phase analysis was performed by the use of a SEIFERT 3003 T/T X-ray diffractometer, with a cobalt source of Co = 0.17902 nm wavelength. X-ray diffraction measurements were performed in the 20÷120° range of angles with an angular step of 0.1°. To interpret the results the diffractograms were described by a pseudo Voigt curve using the Analyze software. A computer software and the DHN PDS, PDF4+2009 crystallographic database were used for the phase identification. The results showed that the crystallite sizes have an effect on the properties of the oxide. It has been shown that the outer oxide layer having larger crystallites, is more porous and thus more brittle. [ABSTRACT FROM AUTHOR]

A palladium-catalyzed, norbornene-mediated tandem amination/cyanation reaction via Catellani-type C-H functionalization was developed using N-benzoyloxyamines as the amination reagent and Zn(CN)2 as the terminating agent. This transformation, in which one C-N bond and one C-C bond are formed, provides an efficient approach for the synthesis of ortho-aminated benzonitriles in one pot from easily accessible starting materials. [ABSTRACT FROM AUTHOR]

The Cδ−H amination of unactivated, secondary C−H bonds to form a broad range of functionalized pyrrolidines has been developed by a triiodide (I3−)-mediated strategy. By in situ 1) oxidation of sodium iodide and 2) sequestration of the transiently generated iodine (I2) as I3−, this approach precludes undesired I2-mediated decomposition which can otherwise limit synthetic utility to only weak C(sp3)−H bonds. The mechanism of this triiodide-mediated cyclization of unbiased, secondary C(sp3)−H bonds, by either thermal or photolytic initiation, is supported by NMR and UV/Vis data, as well as intercepted intermediates. [ABSTRACT FROM AUTHOR]

For the problem of a functionally graded thick-walled tube subjected to internal pressure, we have already presented the elasticity solution based on the Voigt method in Xin et al. (Int J Mech Sci 89:344-349, ). This paper discusses the elastic-plastic problem of the functionally graded thick-walled tube subjected to internal pressure and gives the solution in terms of volume fractions of the constituents. We assume that the tube consists of two linear work hardening elastic-plastic constituents and the volume fraction of one phase is a power function varied in the radical direction. The Lamé constants and yield stress of the constituents of the FGM tube are given rather than Young's modulus and yield stress with different unknown parameters of the whole material in the existing papers. As the internal pressure increases, the deformations of one phase and two phases from elastic to plastic are analyzed. The present method is valid for materials with different Poisson's ratios rather than constant Poisson's ratios usually used in the existing references to obtain the effective Young's modulus. More importantly, the influences of linear work hardening on plastic behavior are considered in this work. [ABSTRACT FROM AUTHOR]

This paper discusses the torsional surface wave in a Voigt-type layer placed over an initially stressed heterogeneous semi-infinite substratum. The heterogeneities in the semi-infinite substratum are thought to emerge as a result of exponential variation in rigidity, density, and initial stress. A closed-form dispersion relation for the torsional surface waves under the considered geometry was obtained. The effect of various technical constants, such as internal friction parameter, stress parameter, heterogeneity parameter, dissipation factor, complex wave number, and thickness of the layer, were studied numerically by plotting various graphs between the nondimensional angular frequencies against the nondimensional real wave number for the torsional surface wave propagation. The numerical solution for the limiting case of torsional surface waves is also presented. In the absence of the considered technical constants, the obtained results are in close agreement with the results obtained by other relevant researchers. The present work exhibits scientific results applicable to the field of earthquake engineering and applied informatics. [ABSTRACT FROM AUTHOR]

'Memory of chirality' (MOC) is an important concept for the development of efficient asymmetric transformations. However, the phenomenon of MOC in C-H functionalization is still rare. In the past decades, three types of intramolecular C-H amination involving C-H insertion of metal nitrenoids, 1-aza-2-azoniaallene salts, and benzamides to construct N-heterocyclic compounds have been developed in Du Bois, Brewer, and our group, respectively. In these reactions, the formation of a C-N bond does not result in the loss of stereochemical information at the stereogenic center. Here, we discuss the scope, mechanism, and application of these transformations and provide a perspective on the development of this field in future. [ABSTRACT FROM AUTHOR]

The Voight reaction is for the transformation of secondary α-hydroxy ketones into corresponding α-amino ketones. Although discovered as early as 1886, it has not enjoyed wide popularity in organic synthesis, as it is applicable to only secondary α-hydroxy ketones. In terms of extending the applications of the reaction, we have shown that the reaction takes place on tert -α-hydroxy ketones also, particularly when present on rigid planar molecular frameworks like phenanthrene, pyrene and acenaphthylene. The reaction is not a simple substitution of the hydroxy group with amines, but goes through imine formation followed by 1,2-C migration. The reaction provides good opportunity for the synthesis of optically active α-amino ketones. We have achieved facile synthesis of some chromatographically separable and optically active tert -α-amino ketones by employing S -(−) or R -(+)-α-methylbenzylamines in the Voight amination. [ABSTRACT FROM AUTHOR]

Significant process intensification of the amination reactions of aryl halides and esters has been demonstrated using continuous flow processing. Using this technology traditionally difficult amination reactions have been performed safely at elevated temperatures. These reactions were successfully conducted on laboratory scale coil reactor modules with 1 mm internal diameter (ID) and on a preparatory scale tubular reactor with 6 mm ID containing static mixers. [ABSTRACT FROM AUTHOR]

In this paper we consider a stabilization problem for an abstract wave equation with delay and a Kelvin-Voigt damping. We prove an exponential stability result for appropriate damping coefficients. The proof of the main result is based on a frequency-domain approach. [ABSTRACT FROM AUTHOR]

In the present paper we study a new generalization of Voigt functions involving the product of generalized Bessel and generalized Whittaker functions. We obtain its explicit representation and then derive partly bilateral and partly unilateral representation and two generating functions. Some special cases of main results have also been given. [ABSTRACT FROM AUTHOR]

In order to solve the velocity profile and pressure gradient of the unsteady unidirectional slip flow of Voigt fluid, Laplace transform method is adopted in this research. Between the parallel microgap plates, the flow motion is induced by a prescribed arbitrary inlet volume flow rate which varies with time. The velocity slip condition on the wall and the flow conditions are known. In this paper, two basic flow situations are solved, which are a suddenly started and a constant acceleration flow respectively. Based on the above solutions, linear acceleration and oscillatory flow are also considered. [ABSTRACT FROM AUTHOR]

The formation of an NCF3 bond or an NCF2R bond still remains scarce. An efficient direct electrophilic amination of fluoroalkyl groups was developed. Difluoroenoxysilanes reacted easily on azodicarboxylate derivatives. These results led to a novel family of NCF3 and NCF2 hydrazine derivatives. [ABSTRACT FROM AUTHOR]

To realize on-line high-accuracy measurement in direct absorption spectroscopy (DAS), a system-onchip, high-precision digital signal processor-based on-line Voigt lineshape fitting implementation is introduced in this paper. Given that the Voigt lineshape is determined by the Gauss full width at half maximum (FWHM) and Lorentz FWHM, a look-up table, which covers a range of combinations of both, is first built to achieve rapid and accurate calculation of Voigt lineshape. With the look-up table and raw absorbance data in hand, Gauss-Newton nonlinear fitting module is implemented to obtain the parameters including both the Gauss and Lorentz FWHMs, which can be used to calculate the integrated absorbance. To realize the proposed method in hardware, a digital signal processor (DSP) is adopted to fit the Voigt lineshape in a real-time DAS measurement system. In experiment, temperature and H2O concentration of a flat flame are recovered from the transitions of 7444.36 cm-1 and 7185.6 cm-1 by the DSP-based on-line Voigt lineshape fitting and on-line integral of the raw absorbance, respectively. The results show that the proposed method can not only fit the Voigt lineshape on-line but also improve the measurement accuracy compared with those obtained from the direct integral of the raw absorbance. [ABSTRACT FROM AUTHOR]

Indirect reductive amination of aldehydes, catalyzed by polymer supported triphenylphosphine-palladium acetate complex PS-TPP-Pd(OAc)2 catalyst have been developed. The imine is prepared with molecular sieves in the first stage, followed by reduction with potassium formate catalyzed by PS-TPP-Pd(OAc)2. The recovered catalyst could be reused for four consecutive cycles without loss in activity and provided an excellent yield of the desired products. [ABSTRACT FROM AUTHOR]

Aluminum-doped zinc oxide (AZO) films were deposited onto amorphous silica substrates using an atomic layer deposition process with diethyl zinc (DEZ), trimethyl aluminum (TMA), and deionized water at 200 °C. Three different Al doping sequences were used at a ZnO:Al ratio of 11:1 within the films. A minimum film resistivity of 1.6×10-3Ω cm was produced using sequential dosing of DEZ, TMA, DEZ, followed by H2O for the Al doping step. This "ZAZW" sequence yielded an AZO film resistivity that is independent of film thickness, crystallographic texture, and grain size, as determined by high resolution x-ray diffraction (XRD). A pseudo-Voigt analysis method yields values for grain sizes that are smaller than those calculated using other XRD methods. Anisotropic grain sizes or variations in crystallographic texture have minimal influence on film resistivity, which suggests that factors other than film texture, such as intragrain scattering, may be important in influencing film resistivity. [ABSTRACT FROM AUTHOR]

In this paper, the properties of the extraordinary mode and surface plasmon modes in the threedimensional (3D) magnetized plasma photonic crystals (MPPCs) with face-centered-cubic lattices that are composed of the core tellurium (Te) spheres with surrounded by the homogeneous magnetized plasma shells inserted in the air, are theoretically investigated in detail by the plane wave expansion method, as the magneto-optical Voigt effects of magnetized plasma are considered (the incidence electromagnetic wave vector is perpendicular to the external magnetic field at any time). The optical switching or wavelength division multiplexer can be realized by the proposed 3D MPPCs. Our analyses demonstrate that the complete photonic band gaps (PBGs) and two flatbands regions for the extraordinary mode can be observed obviously. PBGs can be tuned by the radius of core Te sphere, the plasma density and the external magnetic field. The flatbands regions are determined by the existence of surface plasmon modes. Numerical simulations also show that if the thickness of magnetized plasma shell is larger than a threshold value, the band structures of the extraordinary mode will be similar to those obtained from the same structure containing the pure magnetized plasma spheres. In this case, the band structures also will not be affected by the inserted core spheres. It is also provided that the upper edges of two flatbands regions will not depend on the topology of lattice. However, the frequencies of lower edges of two flatbands regions will be convergent to the different constants for different lattices, as the thickness of magnetized plasma shell is close to zero. [ABSTRACT FROM AUTHOR]

A RhIII-catalyzed addition of aryl CH bonds to nitrosobenzenes, followed by cleavage of the resulting hydroxylamines in situ, has been reported. Different directing groups, such as N-based heterocycles and ketoximes, can be used in this CH amination process, providing valuable diarylamines in excellent yields. Most importantly, this process provides a new method for attaching arylamine groups to aromatic rings. [ABSTRACT FROM AUTHOR]

When an applied magnetic field has an arbitrary direction with respect to the lattice axes of a periodically microstructured or nanostructured metamaterial, the effective permittivity tensor of the metamaterial sample becomes anisotropic and all its components can be nonzero. This is true even if the microstructure has a high symmetry, e.g., cubic or triangular. It is found that the strong magneto-induced anisotropy which appears in the macroscopic response leads to an unusually strong anisotropic behavior of the Voigt effect and other magneto-optical effects. That is, these phenomena become strongly dependent on the direction of the applied static magnetic field, as well as on the direction of the time-dependent electromagnetic field, with respect to the symmetry axes of the periodic microstructure. [ABSTRACT FROM AUTHOR]

Selective α-amination and α-acylation of esters and amides have been developed, employing O-acylhydroxylamines as a dually reactive aminating and acylating reagent. Treatment of zinc enolates with O-acylhydroxylamines provides solely 1,3-dicarbonyl compounds under mild conditions. Introduction of a copper catalyst into the system shifts the reactivity entirely, yielding α-amination products exclusively. [ABSTRACT FROM AUTHOR]

The article discusses the dynamic instability of a thin plate surrounded by a thickness h in the Cartesian system of coordinates, which interacts with an acoustic media that is characterized by the speed of sound. Topics include the formation of a stress-strained state (SSS) in a static system of external forces, the use of the Kirchhoff-Love and Voigt models, and the harmonic vibrations' circular frequency.

In this article, the linear theory of thermoviscoelasticity for Kelvin–Voigt materials with voids is considered. The fundamental solution of the system of equations of steady vibrations is constructed by means of elementary functions and its basic properties are established. The representation of a Galerkin-type solution is obtained. The formula of representation of the general solution for the system of homogeneous equations of steady vibrations in terms of six metaharmonic functions is established. The completeness of these representations of solutions is proved. [ABSTRACT FROM AUTHOR]

A direct approach to important α-amino phosphonic acids and its derivatives has been developed by using copper-catalyzed electrophilic amination of α-phosphonate zincates with O-acyl hydroxylamines. This amination provides the first example of CN bond formation which directly introduces acyclic and cyclic amines to the α-position of phosphonates in one step. The reaction is readily promoted at room temperature with as little as 0.5 mol % of catalyst, and demonstrates high efficiency on a broad substrate scope. [ABSTRACT FROM AUTHOR]

An accurate technique has been developed to calculate the equivalent width of absorption lines. The calculations have been carried out for the pure Doppler and pure Lorentz limiting forms of the equivalent width. A novel expression for the equivalent width for Lorentz profile is given from direct integration of the line profile. The more general case of a Voigt profile leads to an analytical formula that permits a rapid estimate of the equivalent width for a wide range of maximum optical depths. The reliability of the approach is verified using a numerical application calculating the equivalent width for nickel resonance lines at 232.0 and 352.3 nm from atomic absorption (AA) measurements. The dependence of equivalent width on the number density of absorbing atoms is also provided. The results obtained for the equivalent width for the Voigt profile were compared with the data in the available literature obtained by different approaches. [ABSTRACT FROM AUTHOR]

Abstract: Faraday rotation spectroscopy (FAMOS) as well as other modulated techniques that rely on dispersion produce lock-in signals that are proportional to various Fourier coefficients of modulated dispersion lineshape functions of the molecular transition targeted. In order to enable real-time curve fitting to such signals a fast methodology for calculating the Fourier coefficients of modulated lineshape functions is needed. Although there exist an analytical expression for such Fourier coefficients of modulated Lorentzian absorption and dispersion lineshape functions, there is no corresponding expression for a modulated Voigt dispersion function. The conventional computational route of such Fourier coefficients has therefore so far either consisted of using various approximations to the modulated Voigt lineshape function or solving time-consuming integrals, which has precluded accurate real-time curve fitting. Here we present a new methodology to calculate Fourier coefficients of modulated Voigt dispersion lineshape functions that is significantly faster (several orders of magnitude) and more accurate than previous approximative calculation procedures, which allows for real-time curve fitting to FAMOS signals also in the Voigt regime. [Copyright &y& Elsevier]

The spectral line parameters of carbon dioxide have been measured in the laser band I (00011 ← 10001) centred at 10.4 μm. The spectra were recorded at room temperature using the spectroscopic instrumentation at the far-infrared beamline, Canadian Light Source, Saskatoon, Sask. The spectral line intensities, air- and self- broadened Lorentz half widths, and pressure-induced shift coefficients were retrieved for 48 spectral lines using a multispectrum fit technique (Benner et al. J. Quant. Spectrosc. Radiat. Transfer, 53, 705 (1995)). Line parameters were retrieved using the Voigt and speed-dependent Voigt models. The deviations between our results and other results reported in the literature and in the HITRAN08 (Rothman et al. J. Quant. Spectrosc. Radiat. Transfer, 110, 533 (2009)) database were examined and discussed. The effect of errors in fitting channel spectra parameters was examined and found to be mitigated by the inclusion of channels in the multispectral fit. [ABSTRACT FROM AUTHOR]