... CASTING IN VIBRATION MOLDS BY: VA Povidaylo, RI Silin and VA Shchigel' ... Fig.37,Vibrat ory die-casting mold FTD-TT-63-46/I+2 Page 6. ...
DTIC Science & Technology
... Title : Electronic Absorption and Internal and External Vibrational Data of Atomic and Molecular Ions Doped in Alkali Halide Crystals. ...
... Title : Ab Initio Calculation of Vibrational Absorption and Circular Dichroism Spectra Using Density Functional Force Fields. ...
... peaks. Descriptors : *CYCLIC COMPOUNDS, *PYRIDINES, VIBRATION, PYRAZOLES, AMINES, ABSORPTION SPECTRA. ...
... Descriptors : *VIBRATION ISOLATORS, DYNAMIC RESPONSE, DAMPING, RESONANCE ABSORPTION, ENERGY ABSORBERS, ENERGY ...
... INFRARED ABSORPTION IN HEATED AIR FROM VIBRATION-ROTATION BANDS OF NITRIC OXIDE by ... 52 vibration-rotation bands of nitric oxide. ...
This report is concerned with the suppression of self-excited vibrations and the absorption thereof. Technical applications of the suppression of self-excited vibrators are also indicated. (ERA citation 11:007241)
National Technical Information Service (NTIS)
Vibrational absorption (VA) and vibrational circular dichroism (VCD) spectra of (S)-(-)-glycidol were measured in water with a concentration of 6.0M in the 1000-1750 cm(-1) region. Prominent and complex VCD spectral features were detected at the water bending vibrational region. Our ...
PubMed
The absolute structural information about four sets of diastereomers of pentacoordinate spirophosphoranes, derived separately from L (or D)-phenylglycine and L (or D)-phenylalanine, has been obtained by using vibrational circular dichroism (VCD) spectroscopic measurements and density functional theory (DFT) for the first time. Each compound contains a stereogenic centre at the ...
The infrared vibrational absorption (VA) and vibrational circular dichroism (VCD) spectra of methyl lactate in carbon tetrachloride and methanol have been measured in the 1000-1800 cm-1 region. Noticeable changes due to the solute self-aggregation and solvent-solute intermolecular hydrogen-bonding interactions have ...
NASA Astrophysics Data System (ADS)
... used to insure blade integrity, a ... TUNNELS, *TURBOMACHINERY, *COMPRESSOR BLADES, *AXIAL FLOW COMPRESSORS, VIBRATION ...
... Title : The Basic Parameters of Lines and Bands in the Vibrational Spectra of Raman Scattering and Infrared Absorption of Tetramethoxysilane ...
... the parallel band and the perpendicular band. Bands of both the isotopic ... INFRARED SPECTROSCOPY, VIBRATION, ROTATION, MOLECULAR ...
... NOISE ABATEMENT AND INTERNAL VIBRATIONAL ... Although the atomic mechanism leading to ... in a saturating magnetic field lead decrease the ...
Gunter Luepke, Department of Applied Science, The College of William and Mary, Williamsburg, VA 23187 Vibrational lifetimes of hydrogen- and deuterium-related bending and stretching modes in crystalline silicon are measured by high-resolution infrared absorption spectroscopy and pump-probe transient bleaching technique using the ...
... Arlington, VA 22217 1 1 TITLE (Include Security Classification) (Unclassified) Triplet-Triplet Absorption and Polarization Spectra of Anthracene ...
Chiral alpha-methylbenzyl amine is a well known and often used chiral auxiliary, e.g., in the resolution of racemates or asymmetric catalysis. In this work, alpha-methylbenzyl amine and its derivatives N,alpha-dimethylbenzyl amine, N,N,alpha-trimethylbenzyl amine, and bis[alpha-methylbenzyl] amine were investigated by vibrational circular dichroism (VCD) spectroscopy and ...
Vibrational circular dichroism (VCD) spectroscopic measurements and density functional theory (DFT) calculations have been used to obtain the absolute structural information about four sets of diastereomers of pentacoordinate spirophosphoranes derived separately from l- (or d-) valine and l- (or d-) leucine for the first time. Each compound contains three stereogenic centers: ...
The goal of this work is to characterize the intermolecular vibrations of small water clusters. Using tunable far infrared laser absorption spectroscopy, large amplitude vibration-rotation-tunneling (VRT) dynamics in vibrationally excited states of the wa...
The vibrational interaction between an ion and its surrounding configuration strongly influences the absorption and emission spectra that characterize electronic transitions within the ion. The resulting vibrationally assisted electronic absorption and em...
Vibrational absorption (VA) and vibrational circular dichroism (VCD) spectroscopy was applied in the analysis of vibrational and low lying electronic transitions of a triplet ground state cobalt(III) coordination compound. The spectroscopic measurements were performed on the tetrabutylammonium ...
The low frequency vibration energy absorption properties of granular materials have been investigated on an Invert Torsion Pendulum (ITP). The energy absorption rate of granular material changes nonlinearly with amplitude under low frequency vibration. The frequency of ITP system increases a little with granular ...
The multiphoton rotation-vibration energy absorption of diatomic molecules in infrared laser fields is analytically studied using the algebraic approach. The analytical expression of the rotation-vibration transition probability is given. The long-time average absorbed energy spectra and the average number of photons absorbed by the ...
Viscoelastic inserts have many useful applications in noise and vibration suppression of marine and aerospace structures. It is observed that the shape of such inserts play an important role in efficient absorption of vibration. Tapering of viscoelastic inserts may improve noise and vibration reduction in composite ...
Absorption line strengths have been measured at 295 K for the first time for four vibration-rotation
NASA Technical Reports Server (NTRS)
... has been applied to the study of the vibrational modes of ... The absorption band (780-920/cm) consists of overlapping bands at about 835 ...
... grating; 4, focusing mirror; 5, absorption cell; 6 ... large vibrational heat capacity effect insures relatively ... validity of the resonance model above remains ...
... Some vibrational modes showed negative or insensitive dependence of frequency on ... In solid C60 new absorption bands gradually grew with ...
The infrared absorption and reflection in a crystal due to the interaction of the incident electromagnetic field with its vibrational modes are described in this article. The concept of normal vibrations of a crystal is introduced by the example of a line...
... from the vibration-rotation bands of nitric oxide has been calculated with the aid of the SACHA digital computer programs. These band systems ...
Forbidden absorption bands of carbon monoxide in vacuum UV region, noting rotational and vibrational
The photoluminescence and photoinduced absorption are reported for leucoemeraldine and emeraldine forms of polyaniline in the picosecond to nanosecond time domain. The importance of bond vibration, charge tunneling and ring rotations in varying relaxation...
The paper presents experimental data about the absorption band of the stretching vibration of OH(-) in RbCl, KBr, and KCl, and about the field- and stress-induced dichroism of this band at low temperatures. For small concentrations (N(OH)
Measurements of the second vibrational overtone absorption spectrum of the nu3 mode of SF6 are recorded (using a 1 m grating spectrometer). The spectrum was recorded with the grating in the third order using a gas cell cooled by a circulatory dry ice and ...
... CO lasers operating on the lower vibrational bands (4-3, 3-2, 2-1, 1-0) will suffer less atmospheric absorption loss than higher band CO lasers due ...
An extension of the J-diffusion description of rotational motion is developed for the contribution of the rotation-vibration interaction to the linewidths and lineshapes of polarized vibrational Raman scattering, two-photon absorption and two-photon-reson...
The vibrational overtone spectra of gaseous pyridine, 2,6-difluoropyridine, and pyrazole have been recorded using photoacoustic absorption spectroscopy. The pyridine overtone spectrum shows a progression of two peaks at each vibrational level. The widths ...
... originated problems in support of their in-house programs and research programs in vibrational spectroscopy and atomic absorption spectroscopy. ...
... Abstract : The pure rotational and vibrational-rotational absorption bands for a ... The experimental spectral band intensities and contours ...
... BROADENING AND SHIFT OF THE NH SUB 3 VIBRATION-ROTATION LINE BY THE METHOD OF OUT-OF-RESONANCE ABSORPTION OF CO ...
... A machine and the intermediate mass of a two-stage mounting system are considered to be supported by flanges or feet to demonstrate the loss in ...
... The vibrational spectrum of the film shows a dramatic line narrowing effect and resolves several broad absorption features observed in the pellet ...
... to stationary effects of the ion-vibration interaction ... MAGNETIC MATERIALS, IONS, CHROMIUM, VANADIUM, PHONONS, ABSORPTION ...
... LOW VELOCITY, MOLECULAR DYNAMICS, GRAPHITIC FOAM, CARBON NANOTUBES, ACOUSTIC ABSORPTION, FLY ASH, VIBRATION. ...
... in the region of anomalous dispersion, the spectra ... various modes of vibration of solids, directly from ... with regard to problems in solid state physics ...
... Descriptors : *EMISSION SPECTRA, *IONS, *SPECTRUM ANALYSIS, MOLECULAR VIBRATION, EXCITATION, SORPTION, BAND THEORY OF ...
Radiative heating and cooling of solid particles are studied numerically using a molecular dynamics method by considering the vibrational motions of the solid particles and their radiative characteristics of absorption and emission. The radiative absorption and emission are assumed as a function of the vibrational ...
Energy Citations Database
We report on our work with vibrational absorption, vibrational circular dichroism, Raman scattering, Raman optical activity, and surface-enhanced Raman spectroscopy to study protein and DNA structure, hydration, and the binding of ligands, drugs, pesticides, or herbicides via a combined theoretical and experimental approach. The ...
the primary photophysics and photochemistry of LOV2 domains of phototropin 1 of AVena satiVa (oat of the AVena satiVa LOV2 domain has been studied by means of nanosecond to second time- resolved absorption a femtosecond transient ab- sorption study of the LOV2 domains of phot1 of A. satiVa (oat) and of phy3
E-print Network
This paper describes an attractive force microscope using photothermal vibration. A cantilever is vibrated by the optical absorption of a laser beam whose intensity modulation frequency is at resonance frequency, and the vibration is detected by an optical deflection method. The characteristics of the photothermal ...
The abiding problem of vibration absorption has occupied engineering scientists for over a century and there remain abundant examples of the need for vibration suppression in many industries. For example, in the automotive industry the resolution of noise, vibration and harshness (NVH) problems is of extreme ...
spectrum of a sample with two absorption bands. Raman spectra are shown that are excited at a wave- length from resonance Raman spec- troscopy. The absorption spectrum is shown for a sample with two absorption different analytes in the sam- ple, we selectively enhance the vibrational Raman spectrum of different
The mechanism of nonlinear absorption owing to collective absorption by a large number of quasi-resonant vibrational-rotational transitions and two-photon and cascade processes is investigated theoretically and experimentally for the triatomic molecule, ozone. PMID:19730503
Blue chalcedony is one of the precious gems produced in Taiwan, known as "Taiwan Sapphire" in the world. The infrared absorption spectrum and Raman spectrum were employed to study the characters of the vibrational spectrum of the blue chalcedony with different color and texture. It was indicated that the Taiwan blue chalcedony shows the typical spectral ...
The mechanisms and kinetics of the reactions of absorption of oxygen and nitrogen in group VA refractory metals and of the reactions of desorption of oxygen and nitrogen from group VA and VIA refractory metals are treated. The kinetic data are compiled and discussed in connection with problems of practical interest. On the basis of new ...
A survey indicated that high-dose vitamin A (HD-VA) supplements had no apparent effect on vitamin A (VA) status, assessed by serum retinol concentrations, of Zambian children lt 5 y of age. To explore possible reasons for the lack of response, we quantified absorption, retention, and urinary elimination of either a single ...
PubMed Central
in the spectroscopic data for water va- por have significantly increased the near-infrared absorption in models in the cloud-free atmosphere. Approxi- mately 98% of the water-vapor absorption occurs in near-infrared water-vapor lines cannot explain all the absorption observed in the near infrared [e.g. Vogelmann et ...
... G E U Chemistry Program ELECTE 800 North Quincy Street JUN 1 01994 Arlinxton, VA 22217-5000 11. ... MCP* . 1,2-butadiene K12 Distribution I ...
A comprehensive anaytical design procedure for the installation of simple pendulums on the blades of a helicopter rotor to suppress the root reactions is presented. A frequency response anaysis is conducted of typical rotor blades excited by a harmonic va...
The following conclusions were drawn from this study: casks over 9100 kg in mass and their restraining systems can be considered rigid in the vertical direction for the lower modes of vibration. Vehicle bed accelerations for truck transportation system va...
In this study it was hypothesized that the vibration-induced injuries or disorders in a substructure of human hand arm system are primarily associated with the vibration power absorption distributed in that substructure. As the first step to test this hypothesis, the major objective of this study is to develop a method for analyzing ...
In this letter, the ultrafast vibrational dynamics of individual gold nanorings has been investigated by femtosecond transient absorption spectroscopy. Two acoustic vibration modes have been detected and identified. The influence of the mechanical coupling at the nanoparticle/substrate interface on the acoustic ...
Relative spectral absorption coefficients have been calculated for the fundamental vibration-rotation bands of AlO between 2000 and 3500K in the smeared-line approximation. A differential expression is given for the spectral absorption coefficient of indi...
, subpicosecond transient absorption studies of myoglobin in the Soret band,9,19,28,29 Q-band,30 and band III31 to delineate the relationship between the dynamic line shape and the transient response measured at fixed of the broadening and red shift of the transient absorption spectrum. Subsequent vibrational relaxation and cooling
The reaction of HCN isolated in solid argon with H atoms formed by photolysis or by a discharge leads to the stabilization of a sufficient concentration of H2CN for observation of both its vibrational and electronic absorption spectra. Detailed isotopic s...
Theoretically determined frequencies and absorption intensities are reported for the vibrational spectrum of the covalent HOOOH and hydrogen bonded HO---HOO intermediates that may form in the reaction of the hydroxyl and hydroperoxyl radicals. Basis sets ...
Some recent applications of surface vibrational spectroscopies to electrochemical and related interfacial systems are illustrated by means of studies undertaken in the authors' laboratory. The utility of infrared reflection-absorption spectroscopy (IRAS) ...
Hydrogen and deuterium were implanted into silicon with different impurities content. It is found, that absorption at 800-900 and 1500-1800/cm regions are identified with vibrations of H(+) and H(-) ions. It is shown, that H atom has donor level at the up...
The spectrum of the first through fifth vibrational overtone absorptions of cycloheptatriene are reported. The spectrum for the first and second overtones were recorded using a liquid sample while the third, fourth, and fifth overtones were recorded for t...
The gaseous near infrared and visible absorption spectra of pyrrole and pyrrolidine have been measured for the first through fourth N-H stretch vibrational overtones and the second through fourth C-H stretch overtones. The C-H overtone features follow the...
The vibrational overtone spectra of gaseous pyridine, 3-fluoropyridine, 2,6-difluoropyridine. and pyrazole have been recorded using photoacoustic absorption spectroscopy. The pyridine, 3-fluoropyridine, and 2,6-difluoropyridine overtone spectra exhibit tw...
ABSORPTION SPECTRUM OF BENZENE IN THE 2000A REGION: Temperature dependence of vibrational transitions in the second electronic transition of benzene was studied. All the vibrational levels observed by Pickett (L. W. Pickett, et al. J. Am. Chem. Soc., 73:4...
The isolation of machinery vibration from rigid and nonrigid substructures is described in uncomplicated terms. One- and two-stage mounting systems, single and multiple antivibration mountings, and beamlike and platelike substructures are examined. A mach...
The infrared absorption spectra of gaseous 3-pyrroline and pyrrolidine are presented. These spectra are compared to pyrrole and previous work on liquid pyrrolidine. Also presented is the vibrational overtone spectrum of 3-pyrroline. Three vibrational over...
Background: Resonant microwave absorption has been proposed in the literature to excite the vibrational states of microorganisms in an attempt to destroy them. But it is extremely difficult to transfer microwave excitation energy to the vibrational energy...
A tunable diode laser is used to investigate the nu sub 8 vibrational band of Sulfuryl Fluoride in the 11 micrometer region. Although the absorption spectrum is doppler limited, the resolution is high enough to observe previously unresolved lines and ther...
During the past grant period the mechanism behind the nonresonant UV pumping of the IR vibrational fluorescence for CN(-) in alkali halide crystals has been determined. First an F-center is produced by two UV photon absorption, then the F-center is ionize...
A crossed beam study of the rotational and vibrational energy transfer hydrogen and glyoxal collisions is reported. A laser pumped rotational states in the absorption spectrum of glyoxal and the resulting emission was monitored.(AIP)
... experiments. A, top-view camera; B, oscilloscope; C, laptop computer; D, side-view camera; E, vibration absorption ... the middle. Pulse trains were delivered using a laptop computer, and signal outputs w...
NBII National Biological Information Infrastructure
In the coming decade, UV spectroscopy of Titan's atmosphere should appear as a powerful diagnostic tool which is likely to complement IR and microwave spectroscopy and future in situ experiments in the study of organic chemical processes which, on the Earth, could have led to the emergence of life. However, the interpretation of albedo spectra in the mid-UV range is critically dependent on the ...
Natural fluorite crystals containing oxygen impurities are colored electrolytically by using a pointed cathode and a flat anode at various temperatures and voltages. F and F(2) color centers are produced in colored fluorite crystals. O(2-)-V(a)(+), O(2-)-V(a)(+) aggregate, Yb(2+), Ce(3+) and Sm(2+) absorption bands are observed in ...
Previous work reported by various researchers has shown that absorption of unwanted vibration can be accomplished by means of suitably arranged autoparametric interaction between the vibrating component and an added-on absorber element. This theme is developed, and a method for the enhancement of two-mode autoparametric interaction is ...
A vibrational progression that is hidden in a featureless spectrum of induced absorption and stimulated emission was found in time-resolved absorption change spectra. The ultrahigh time resolution of the pump-probe measurement made by using an ultrashort laser pulse localizes the wave packet along the potential multimode hyper ...
OH?-doped KBr polycrystals were colored electrolytically by using a pointed cathode and a flat anode. Characteristic O?, OH?, U, Cu+ and O-Va+ absorption peaks were observed in resolved absorption spectrum of uncolored polycrystals. Herein the position of the O-Va+ absorption peak at room ...
A recent survey indicated that high-dose vitamin A supplements (HD-VAS) had no apparent effect on vitamin A (VA) status of Zambian children <5 y of age. To explore possible reasons for the lack of response to HD-VAS among Zambian children, we quantified the absorption, retention, and urinary elimination of either a single HDVAS (60 mg) or a smaller ...
DOE Information Bridge
Vibrational levels of the ground states ((2)pi (1/2), 3/2) of nitric oxide are populated by transfer of vibrational quanta in collisions with molecular oxygen and nitrogen; by atom exchange with atomic oxygen; by absorption of infrared radiation from the earth's surface, the lower atmosphere, and the sun; by fluorescent decay of the ...
The vibrational relaxation of the bending mode of HDO in liquid D2O has been studied using time-resolved mid-infrared pump-probe spectroscopy. At short delays, the transient spectrum clearly shows the v = 1 --> 2 induced absorption and v = 1 --> 0 bleaching and stimulated emission, whereas at long delays, the transient spectrum is dominated by the ...
... The utility of infrared reflection-absorption spectroscopy (IRAS) for linking the structural behavior of absorbates on ordered metal surfaces in ...
... and compared to previous results o aniline. ... ENERGY, SOLVENTS, ABSORPTION, ATTENTION, ANILINES, FLUORESCENCE, CLUSTERING. ...
... Abstract : Rotationally resolved absorption spectroscopy in the AX (0,0) vibrational band system of OH around 306.4 nm has been performed to ...
... of the electronic, vibrational, and rotational wave functions. ... The frequency, "H" function, and "E" function must now ... apart from an arbitr.airy constant) ...
This page is a set of concept test questions about organic chemistry spectroscopy. There are ten questions about topics including trans isomer and NMR spectra, C-X vibration, wavenumber absorption, and carbon signals.
NSDL National Science Digital Library
The absorption in silicon for the 8 to 12 micrometer region depends on the amount of oxygen contamination in the sample and on the intrinsic or lattice vibrations of the sample. The oxygen contamination component can be eliminated if the total number of o...
... Investigations of the absorption spectrum of nitric oxide in polar solvents led to the discovery of a band with well resolved vibrational fine structure ...
The considerations involved in the choice of a suitable hose for slurry transportation are described. Hoses have the advantages of flexibility, vibration absorption and abrasion resistance. Brief information on installation is given.
A correlation is made between the EPR spectra and the IR absorption bands for the known multivacancy-oxygen complexes in irradiated silicon. John Simon Guggenheim Fellow
A correlation is made between the EPR spectra and the IR absorption bands for the known multivacancy-oxygen complexes in irradiated silicon. (Author)
... Figure 2. Comparison of the Loss Factor-Temperature Curves for Nitinol, ... strengths in the 37,000 - 42,000 psi range with good corrosion ...
... Report Date : NOV 1976. ... Cobalt-iron alloys with additions of aluminum and manganese, copper-aluminum-nickel alloys, iron-chromium-aluminum ...
... 1 Sep 74-1 Mar 75,. ... In addition preliminary experiments on nickel and a cobalt nickel alloy show that magnetostrictive effects can be employed to ...
... Title : IR Transition Moments and Collisional Dynamics of Vibrationally Excited OH Radicals via Time-Resolved Laser Absorption Spectroscopy. ...
... a detailed description of two single-photon absorption cross ... Our detection apparatus is too slow to ... avalanche discharge.) The output from the ...
is slow compared to the motion of the electrons, the Born-Oppenheimer approximation. (ref. 17) may be applied to the pair of molecules collectively. ...
NASA Website
vibration) have infrared absorption spectra. A typical infrared spectrum - in ... -NO2 , and C-Cl normally absorb in a particular region, infrared spectra ...
Electron tunneling through bridge molecular groups with a strong coupling to a local quantum vibrational mode is considered. A scheme is suggested for direct experimental observation of the effect of internal conversion of vibrational quanta in inelastic electron tunneling. The effect consists of excitation and re-absorption of ...
The effects of calcium (Ca) intake (V(I)), age and growth rate on intestinal Ca absorption were studied in growing dogs. Two breeds of dogs differing in their growth rate (67 Great Danes and 23 Miniature Poodles) were raised on diets differing only in their Ca content (range 0.33 to 3.3 g/100 g diet on a dry matter basis). Repetitive Ca balance studies were performed with the ...
Pour-depressant additives based on EVAC (ethylene/vinyl acetate copolymer) are used to improve low-temperature properties of petroleum. The quality control is the content of bound VA (vinyl acetate). This article introduces the PR spectrophotometer method to determine the bound VA. Means of diluting gel additives for control samples are detailed. An ...
Experimental measurements of sound absorption in air, measurements of ultrasonic absorption in H2O/O2 mixtures at 500 K reported here, and experimental measurements in mixtures of H2O with other impurities have been analyzed to determine the energy transf...
Attenuation of infrared radiation in the troposphere is dominated by water vapor absorption. Most past work on the spectroscopy of water vapor has been on the analysis of the rotational and vibrational bands. As a result a thorough listing of line positio...
Fourteen bands of ozone between 500 and 3300 per cm have been identified and values of the vibrational anharmonic constants determined. The integrated band absorptances of many of these bands have been measured from spectra of a 32 m path of ozone-oxygen ...
The infrared absorption of some polycrystalline alkali metal and alkaline earth formates was measured in the region of 500 cm/sup 1/ to 3000 cm/ sup -1/. The observed crystal splitting of the formate fundamentals is discussed in terms of a vibrational analysis under the factor group. (auth)
In the field of corrosion and hydrogen absorption by the metal, the effects of the following factors are studied: thermal flux; vibrations; pressure; the addition of lithium hydroxide; and thermal cycling. These factors may all be met in the operation of reactors. (auth)
Measurements of the visible absorption and Raman intensity dispersion of I2 molecules dissolved in chloroform are reported. The absorption spectrum is adequately interpreted by means of a simple model for the excited state vibrational wave function. The m...
The dissociation of highly vibrationally excited molecular ions resulting from single infrared photon absorption has been studied. The wavelength dependence of the absorption/dissociation process has been measured, and the photofragments identified. Measu...
To check the reported data on the infrared emission band of 1890/cm and to find another band belonging to the deformation vibration Pi(i)(+), the infrared absorption spectrum of B2O2 vapor in the 230-4000/cm range was studied.
The pure Stark effect, intensity enhancement by external electric fields, and charge transfer effects are three mechanisms by which vibrational transitions in molecules at or near metal surfaces may be observed in addition to conventional absorption.
The diffusion-absorption heat pump offers advantages including no moving parts, noise and vibration free operation and operation without electric power. An example of such a cycle is the gas-fired domestic refrigerator. The cycle is similar to an absorpti...
A discussion of absorption phenomena in the infrared (2. 5 - 15 micrometers) spectral region is presented. Mechanisms surveyed include the attenuation of electromagnetic waves by dielectrics and metals; molecular absorption processes; lattice vibrations i...
Extended x-ray-absorption fine-structure measurements on Nb/sub 3/Ge at temperatures from 8 to 300 K using the Nb K edge show large anisotropies in nearest-neighbor vibrational correlations arising from one-dimensional transition-metal chains in the A15 structure. A simple view of these vibrations involves combinations of optical ...
The fluid flow inside turbine governing valve is 3D unsteady turbulence. The interaction between the structure of the valve and the fluid flow may induce vibration of valve disc and valve rod, even more damage. In this article, 3D modeling of the shaped governing valve is established. In the valve calculation and experiment, variation regularity of the flow parameters is ...
Multiphoton absorption of 2,5-bis[4-(2-N,N-diphenylaminostyryl)phenyl]-1,3,4-oxadiazole was experimentally studied by using femtosecond laser pulses. This material demonstrates a very broad multiphoton absorption band of around 300 nm width with two peaks of 1250 and 1475 nm. The first peak results from the three-photon absorption ...
In this undergraduate physical chemistry laboratory experiment, students acquire a high-resolution infrared absorption spectrum of carbon dioxide and use their data to show that the rotational-vibrational state populations follow a Boltzmann distribution. Data are acquired with a mid-infrared laser source and infrared detector. Appropriate ...
ERIC Educational Resources Information Center
Electromagnetic and hadronic cascade features are reviewed as they pertain to Cherenkov detection. By a sample of devices, the design and performance of detectors that make use of these features in various ways, through a large range of applications to va...
... Personal Author(s) : Vorobev,AA ; Vorobev,VA ; Zavadovskaya,EK ; Sokolov,GP ; Pushkin,AV. Report Date : 25 AUG 1977. ...
... Personal Author(s) : Vorobev,AA ; Vorobev,VA ; Zavadovskaya,EK ; Sokolov,GP ; Pushkin,AV. Report Date : 18 DEC 1973. ...
... Arlington, VA 22217-5000 TELECON 8/6/90 VG 4 Page 6. Low temperature ( 14 K) absorption spectra of InAlAs / InGaAs MOW sample . . . ...
The opportunity of detecting vibrationally excited ozone molecules using UV absorption spectroscopy in the Hartley band was studied. The proposed approach is based on comparing the experimentally measured absorption spectrum with the simulated one. For this purpose the absorption spectra for 35 lower ...
The mechanism of nonlinear absorption owing to collective absorption by a large number of quasi-resonant vibrational-rotational transitions and two-photon and cascade processes is investigated theoretically and experimentally for the triatomic molecule, ozone. The suppression of saturation at infrared intensities between 10 to the 4th ...
We report transient absorption measurements on poly(3-hexyl thienylene) and poly(3-dodecyl thienylene). In both materials we observe a transient absorption followed by a transient bleaching, and oscillations with a period of 120 fs. We propose that the oscillatory features are due to coupling between vibrational modes of the polymer ...
The visible absorption spectrum of liquid ethylene at ? 108 K from 5500 � to 7200 � was measured by using a pulsed tunable dye laser, immersed-transducer, gated-detection opto-acoustic spectroscopy technique. The absorption features show the strongest band with an absorption coefficient of ?2 � 10-2 ...
The vibrational spectrum of B2C has been observed for the first time in solid argon by Fourier-transform infrared spectroscopy. Absorption frequencies of the three boron isotopomers of cyclic symmetric B2C, previously deduced by ab initio theory, are in accord with measured frequencies, which enables assignment of an absorption at ...
The authors improved the accuracy of the method of universal functions (MUF) for estimating total band absorptances and their derivatives for nonoverlapping Lorentz-profile lines of vibration-rotation bands for linear molecules and symmetric tops. The MUF accuracy is estimated for the CO2 ?2- and ?3-fundamental bands and the Doppler line shape. The MUF has ...
Starting from a simplified analytic model of the CO laser, we have analyzed the influence of transitions to a single vibrational-rotational branch of a CO molecule, and associated resonant self-absorption, on the CO vibrational distribution function. We have also investigated the gain saturation characteristics, focusing on pumping ...
The results of numerical calculations of the temperature dependence of the width and position of the fundamental lattice-vibration absorption peak in NaCl and LiF are presented. The calculations are carried out in the high-temperature limit, on the basis ...
Infrared reflection absorption spectroscopy (IRRAS), using polarization modulation and tunable diode laser excitation, has been applied to the study of the vibrational modes of subsurface oxygen on A1 (111). The dependence of the spectra on O2 exposure an...
We present the IR absorption and surface-enhanced Raman scattering (SERS) spectra of the isoquinoline alkaloid berberine adsorbed on a silver hydrosol and on the surface of a silver electrode for different potentials. Based on quantum chemical calculations, for the first time we have assigned the vibrations in the berberine molecule according to ...
The experimentally determined eletronic energy levels of approximately 500 neutral and ionic transient molecules possessing from 3 to 6 atoms are tabulated together with the associated vibrational structure, the radiative lifetime, the principal rotational constants, and references to the pertinent literature. Vibrational and molecular beams, and in ...
Spectral data for more than 70 atomic and molecular ions doped in alkali halide crystals are tabulated. The tables include electronic absorption data, listings of internal vibrational frequencies of doped complex ions, and tabulations of the frequencies o...
Anharmonicity in the lattice vibrations of oxygens in UO(2) has been examined by using EXAFS of the U L(III) absorption edge. While the EXAFS determined U-U distance of 3.89 A closely matches the crystallographic separation, the U-O distance of 2.43 A is ...
The D2O absorption spectrum recorded with a selective modulation Girard spectrometer in the region of 3690-4190 cm-1 (resolution ~0.07 cm-1) has been analyzed. Based on the fitting of experimental data the spectroscopic parameters of the vibrational state (011) have been determined and the parameters of the vibrational states (110) and ...
Relative absorption coefficients have been calculated for the infrared vibration-rotation spectrum of FeO using the smeared-line model. Band-heads occur in the R-branch. Line-by-line calculations show that errors incurred through the use of the just-overl...
In this paper, we present a theoretical approach to construct a fluctuating quantum model of the CO vibration in heme-CO proteins and its interaction with external laser fields. The methodology consists of mixed quantum-classical calculations for a restricted number of snapshots, which are then used to construct a parametrized quantum model. As an example, we calculate the ...
The present paper reports the theoretical and experimental vibrational spectra of organophosphorus pesticide parathion-methyl in the frequency range from 0.2 to 2.0 THz respectively. Under the room temperature and nitrogen conditions, the absorption peaks were found at 0.65, 1.33, 1.81 and 1.91 THz, and the average refractive index was 1.39 based on the ...
The vibrational frequencies of the singlet excited state of Mg-substituted myoglobin and relative absorption probabilities were determined by fluorescence line-narrowing spectroscopy. These spectra contain information on the structure of the excited state species, and the availability of vibrationally resolved spectra from excited ...
The vibrational relaxation times of HF(v = 1, 2, and 3) were measured in H2, N2, and CO2 by a laser-induced fluorescence technique. The upper vibrational levels were produced by sequential absorption in which HF(v = 0) was pumped first to HF(v = 1) and su...
A general expansion is derived for the transition moment between two nondegenerate vibrational states of a polyatomic molecule. This analysis is combined with ab initio surfaces for the potential energy and the dipole moment of water vapor to predict integrated band absorption intensities. Calculations are compared with experiment for several transitions ...
Signals of transient absorption and relaxation processes in gaseous mixtures of H{sub 2}Se with He, Ar, and HCl are investigated by way of selective vibrational excitation. Noticeable disagreement between theoretical and experimental values of the vibrational relaxation rates is found. 9 refs., 1 fig., 3 tabs.
and the cannot be distinguished from the absorption. The vibrational dynamics of absorbers have been widely, 2002 Vibrational relaxation and hydrogen bond dynamics in methanol-d dissolved in CCl4 have been vibrational relaxation and hydrogen bond dynamic events occur with very similar amplitudes and rate constants
The extensively perturbed spectrum of the asymmetric methyl stretching vibration of [ital trans]-ethanol near 2990 cm[sup [minus]1] has been reinvestigated via direct absorption infrared spectroscopy at a resolution of 30 MHz. A ground state combination difference analysis of the vibrational state mixing is presented for the upper ...
) in the submonolayer regime induces a red-shift of the CO vibrational frequency. Atomic oxygen, formed on Cu(100 to environment.1-4 The change in the vibrational frequency of CO due to other atomic and molecular adsorbates atoms on the CO vibrational frequency were investigated by adsorbing CO on a NO-covered Cu surface
contribution to the vibrational relaxation rate for an adsorbed H atom on Cu(111) from infrared vibrational of the surface plane. �h! h is the calculated vibrational energies for the H atom normal to the surface�oteborg University, S�412 96, G�oteborg, Sweden B. Hammer Center for Atomic�Scale Materials Physics and Physics
Traditional dynamic vibration absorber (DVA) is widely used in industries as a vibration absorption equipment. However, it is only effective at narrow working frequency range. This shortcoming has limited its stability and application. This paper develops an adaptive tuned vibration absorber (ATVA) based on unique ...
Infrared absorption spectra of Bi-system high zero resistance temperature (Tc) superconductors were measured. The relation between Cu-O bond stretching vibration in CuO2 plane and superconducting properties of Bi-system high Tc superconductors were analysed and discussed. The result of analysis indicated that the change of absorption ...
The subpicosecond photoinduced proton-transfer cycle of 2-(2'-hydroxy-5'-methylphenyl)benzotriazole creates ground state molecules with a highly excited vibrational system. As a result, the S(sub 0)-S(sub 1) absorption shows a drastic broadening in the picosecond regime that is directly monitored in temporally and spectrally resolved experiments. The ...
Terahertz (THz) spectra were obtained for polylactide, and they were analyzed by numerical calculations based on density functional theory. An absorption band was observed at approximately 50 cm-1, which becomes larger when the THz electric field is parallel to the sample drawing direction. An absorption peak with a similar directional dependence appears ...
Based on the multiexciton expansion of a model Hamiltonian, an accurate quantum-dynamical description of vibrational states formed by amide modes in alpha-helical polypeptides is presented. Using the multiconfiguration time-dependent Hartree method, linear and pump-probe infrared absorption spectra are calculated by numerical time propagation of the ...
The terahertz spectra of four kinds of vitamins are presented. The refractive index and absorption spectra of these vitamins are obtained by the terahertz time-domain spectroscopy. The full-geometry optimizations and frequency calculations using the density functional theory are applied to obtain the structure and vibration frequencies of these vitamin ...
The spectral absorption features of methamphetamine (MA), one of the most widely consumed illicit drugs in the world, are studied experimentally by Terahertz (THz) time-domain spectroscopy (THz-TDS), and the characteristic absorption spectra are obtained in the range of 0.2 to 2.6 THz. The vibrational frequencies are calculated using ...
After a short review of a generic vibrational model of ir multiple-photon excitation, the model is generalized to include rotations. It is shown that the combination of chaotic dynamics and rotational averaging leads to fluence-dependent absorption which removes the sensitivity of the results to model-dependent parameters. The classical ...
Analytical formulas are proposed for the coefficients that determine broadening of vibrational-rotational absorption lines of diatomic and linear molecules in the case when the broadening is caused by the pressure of buffer gases or linear molecules. The formulas are obtained by the parameterization of the semiclassical method relations with allowance for ...
A mini-handbook for the selection and application of commonly available noise and vibration control materials is presented. Basic information on the characteristics of sound absorptive, sound barrier, vibration damping, and vibration isolation materials are provided. Materials include: diaphragm absorbers, resonant ...
The velocity constants of the reaction between deuterium atoms and vibration-excited hydrogen molecules were investigated. The measurements were performed in a thermostatically controllable flow reactor, coupled with an atomic line resonance absorption detection method. The state-specific velocity constant of the reaction is determined as a function of ...
Recent advances in the active control of noise and vibration are examined in reviews and reports. Topics addressed include the aerodynamic potential of antisound, functional monotony and diagonal control in synchronous vibration absorption, active minimization of acoustic fields, and energy flow in active control systems. Consideration ...
The structure of the linear infrared absorption spectrum of the N-H stretching mode in 7-azaindole dimers is analyzed by quartic anharmonic vibrational force field calculations based on density functional theory. It is demonstrated that a multiple Fermi resonance model including contributions from 12 fingerprint vibrational modes, most ...
The absorption spectra of stretching vibrations of H$sub 2$O, HDO, and D$sub 2$O vapor and bending vibrations of H$sub 2$O vapor are measured at densities of 0.003--0.11 g/cm$sup 3$. Absorption due to associated water molecules is identified. The absolute absorption band intensities of ...
We study the quantum dynamics of the cavity optomechanical system formed by a Fabry-Perot cavity with a thin vibrating membrane at its center. We determine in particular to what extent optical absorption by the membrane hinders reaching a quantum regime for the cavity-membrane system. We show that even though membrane absorption may ...
The spectra of anhydrous uranyl nitrate in organic solvents were investigated in the range from 360 to 500 m mu . The spectra retained their vibrational character in all investigated solvents and do not differ markedly from those of the sesquihydrate and other hydrates. The appearance of 10 absorption bands in the range 20,000 to 28,000 cm/sup ...
Interstitial hydrogen in rutile TiO2 is studied by infrared (IR) absorption. The measurements identify this defect as a shallow donor with an ionization energy of 10 � 1 meV. The IR absorption lines at around 3290 cm-1 include local vibrational modes (LVMs) of the neutral and the positive charge states of the donor. The neutral ...
HD spectra was studied in the UV about as thoroughly as those of H/sub 2/. The vibration-rotation line positions are known. However, the theory does not do well in calculating the absorption strengths. These tend to be stronger than the quadrupole strengths for H/sub 2/ and so more lines were measured. The state of knowledge of the HD line positions of ...
Initial relaxation kinetics in a series of carotenes has been investigated using femtosecond absorption and Raman spectroscopy. The internal conversion from the photoexcited 1Bu+ state to the 2Ag- state is faster in the carotenes with middle polyene lengths. The vibrational relaxation of the 2Ag- state has fast and slow components. The time constant of the ...
Vibrational spectroscopy, commonly associated with IR absorption and Raman scattering, has provided a powerful approach for investigating interactions between biomolecules that make up cellular membranes. Because the IR and Raman signals arise from the intrinsic properties of these molecules, vibrational spectroscopy probes the ...
We have shown previously that selective vibrational excitation of reactants can lead to bond-selective and mode-selective control of gas-phase reactions such as the dissociation of water and hydrogen abstraction from methane isotopologues. Our present work seeks to extend this vibrational control to the solution phase, exploring the effect of ...
The present study shows that a passive system of vibration protection, which combines principles of vibration isolation and dynamic absorption, can be effectively used in hand-held percussion machines. The vibration isolator between the handle and the casing of the machine reduces the high-frequency components of ...
A novel tunable vibration absorber (TVA) is developed for active absorption of vibrations in vibrating structures. The TVA is composed of a piezoceramic sensoriactuator suspended in a mounting frame by two flexible beams connected to axial ends of the sensoriactuator. The sensoriactuator serves to produce an axial ...
The present paper is devoted to analyzing undamped forced transverse vibrations of an elastically connected complex double-beam system. The problem is formulated and solved in the case of simply supported beams. The classical modal expansion method is applied to ascertain dynamic responses of beams due to arbitrarily distributed continuous loads. Several cases of particularly ...
The absorption of IR radiation in ozone is investigated theoretically and experimentally as a function of the radiation intensity in the range 1 kw/sq cm - 3 Gw/sq cm. Nonlinear absorption spectra of ozone are obtained for tuning over the CO2-laser emission lines in the region 970-1090 per cm. The absorption mechanism typical of ...
