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1.
I. S. Mikhalovsky M. V. Samoylov N. P. Wileishikova 《Journal of Applied Spectroscopy》2009,76(1):127-131
IR spectroscopy is used for a comparative analysis of the trans-isomerization of double bonds in hydrocarbon residuals of lactic and hydrogenated lipids. The maximum of the absorption band
of the trans-isomers for all the lipid samples is found to lie at 965 cm−1. An absorption band at 970 cm−1 is discovered in the spectra of the lactic lipids near the analytic band of the trans-isomers at 965 cm−1. Based on a gaussian approximation for their absorption spectral bands, the trans-isomer content in the lactic lipid samples is 10–11%. The absorption by lipid molecules at 970 cm−1 has to be taken into account when determining the trans-isomer content of fat and oil products.
Translated from Zhurnal Prikladnoi Spektroskopii, Vol. 76, No. 1, pp. 138–142, January–February, 2009. 相似文献
2.
For the first time, we have assigned the observed absorption bands and interpreted the IR spectrum of methyl-β-D-glucopyranoside
in detail in the 1500–800 cm−1 region, based on a full calculation of the frequencies and absolute intensities of the normal vibrations of the molecule
and their comparison with the experimental data. We have identified two groups of spectral signs indicating an oxymethyl substituent
has replaced the hydroxyl group on the C(1) atom in the glucopyranoside: absorption bands of medium intensity due to the characteristic vibrations of the substituent,
and intense bands due to an unusual “interaction” between many structural moieties.
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Translated from Zhurnal Prikladnoi Spektroskopii, Vol. 73, No. 6, pp. 721–727, November–December, 2006. 相似文献
3.
G. A. Zalesskaya V. S. Ulashchik N. P. Mit’kovskaya O. V. Laskina A. V. Kuchinskii 《Journal of Applied Spectroscopy》2007,74(5):738-743
We used IR Fourier absorption spectra of blood to study changes in the structure of globular blood proteins with extracorporeal
autohemomagnetotherapy, used to treat ischemic heart disease. We compare the spectra of blood before and after magnetotherapy
in the regions: amide I (1655 cm−1), amide II (1545 cm−1), amide III (1230–1350 cm−1), amide IV and amide V (400–700 cm−1). We have shown that pronounced changes in the spectra in the indicated regions on direct exposure of blood in vivo to a
low-frequency pulsed magnetic field are connected with conformational changes in the secondary structure of globular blood
proteins, which are apparent in the increase in the contribution of the α-helix conformation. We discuss the magnetotherapy-initiated
appearance of new IR absorption bands at 1018 and 1038 cm−1 and an increase in the intensity of a number of other bands located in the 1000–1200 cm−1 region, which suggests a change in the concentration of some blood components.
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Translated from Zhurnal Prikladnoi Spektroskopii, Vol. 74, No. 5, pp. 665–669, September–October, 2007. 相似文献
4.
L. Kovács M. Mazzera E. Beregi R. Capelletti 《Applied physics. B, Lasers and optics》2009,94(2):273-277
Several weak absorption bands have been observed in the optical absorption spectra of pure and rare-earth-doped YAl3(BO3)4 single crystals in the 3350– 3650 cm−1 wave number region. Two of them, peaking at about 3377 cm−1 and 3580 cm−1 in the 8 K spectra, appear in most of the samples. They are tentatively attributed to the stretching mode of OH− ions incorporated in the crystal during the growth. An additional absorption band at about 5250 cm−1 at 8 K has also been detected in almost all samples. The temperature and polarization dependences of these bands, and their
possible origin, are discussed. 相似文献
5.
A. V. Bazhenov V. V. Kveder A. A. Maksimov I. I. Tartakovskii R. A. Oganyan Yu. A. Ossipyan A. I. Shalynin 《Journal of Experimental and Theoretical Physics》1998,86(5):1030-1034
Raman light scattering and IR absorption spectra of samples containing multilayer carbon nanotubes in different stages of
purification by the selective oxidation technique have been investigated. It was found that the Raman spectra of carbon nanotubes
exhibit softening of the mode at 1582 cm−1 corresponding to E
2g
vibrations of graphite hexagons and a line at 120 cm−1 due to the radial vibrations of nanotubes. In IR absorption spectra measured in the region of 0.07–0.3 eV, several sets of
lines with a spacing of 15 meV (120 cm−1) between lines of each group have been detected. We suggest that each group corresponds to electron transitions generating
electron-hole pairs in semiconducting nanotubes and contains a phononless 00-line and its phonon replicas with spacing between
them equal to the “breathing” mode energy of 120 cm−1. Measurements of electric conductivity at a frequency of 9300 MHz indicate that, in addition to semiconducting nanotubes,
the samples contain nanotubes with properties of a highly disordered semimetal.
Zh. éksp. Teor. Fiz. 113, 1883–1891 (May 1998) 相似文献
6.
N. M. Shishlov Sh. S. Akhmetzyanov S. L. Khursan 《Russian Journal of Physical Chemistry B, Focus on Physics》2010,4(5):846-859
IR spectroscopy measurements show that films of poly(diphenyl sulfophthalide) (PDSP), a cardo polymer, interact with atmospheric
moisture during storage at room conditions. A total of 15 absorption bands were isolated in spectra of PDSP hydrated during
storage, which belong to sorbed water and hydrolysis products. A number of absorption bands (within 1500–1800 cm−1 and 980–1100 cm−1) were obtained by subtracting the spectrum of the film after heating from that of the initial hydrated film. At least six
individual bands in the region of the O-H bond stretching vibration were isolated by decomposing a broad complex band (3700–2000
cm−1) into Gaussian components. The isolated bands were tentatively assigned based on the available literature data and quantum-chemical
calculations of the characteristics of a number of complexes of a diphenyl sulfophthalide model compound with water molecules.
The IR spectra and energies of the hydrogen bonds formed were calculated at the B3LYP/6-311G(d, p) level. In particular, the absorption bands at 1010 and 1079 cm−1 were assigned to the symmetric stretching vibrations of the S=O bonds in the −SO3− anion, the 1062-cm−1 absorption band, to ν(C-OH), and the absorption bands at 3646, 3586, and 3475 cm−1, to complexes of water with sulfophthalide cycles of the polymer. After a long storage, PDSP largely transforms into a polymeric
oxonium salt, and its spectrum becomes similar to that of a polymeric salt prepared by alkaline hydrolysis. A general mechanism
of the interaction of PDSP with water is proposed, according to which the hydrolysis of the sulfophthalide cycles (SPC) by
sorbed water yields new hydrophilic groups, sulfoacid, and hydroxyl groups. A further sorption of water by the sulfoacid results
in its ionization and the formation of various hydroxonium forms. Sorption and hydrolysis are reversible processes: water
is desorbed and the SPC is recovered when the polymer is heated to 100–150°C, as can be judged from an increase in the intensity
of the S=O bond vibrations of the sulfophthalide cycle at 1352 and 1192 cm−1. The possibility of using strongly hydrated PDSP for manufacturing proton-conducting membranes is discussed. 相似文献
7.
We present the results of a spectral study of the effect of low-intensity laser radiation on the molecular structure of blood
and blood components. Analysis of the Fourier transform IR absorption spectra of blood confirmed the changes we observed previously
in the oxygen transport characteristics of blood with intravenous exposure to the emission from a He-Ne laser. We show that
structural and conformational changes in the hemoglobin tetramer, initiated by laser-induced photoreactions between Hb and
oxygen, lead to characteristic changes in the shape and intensity of the IR bands for NH stretching vibrations, and also the
amide I and amide II absorption bands. In the IR spectra of irradiated blood samples, we note increased absorption in the
bands for stretching vibrations of the phosphate groups (945–1280 cm−1), which is evidence for an increase in the nucleic acid content (DNA, RNA). In the spectra of plasma and erythrocytes prepared
from irradiated blood, there are no changes in this region of the IR spectrum. At the same time, in the IR spectra of samples
of irradiated plasma, the intensity of the bands for stretching vibrations of the CH2 groups increases substantially.
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Translated from Zhurnal Prikladnoi Spektroskopii, Vol. 73, No. 1, pp. 106–112, January–February, 2006. 相似文献
8.
9.
M. Bryushinin V. Golubev Y. Kumzerov D. Kurdyukov I. Sokolov 《Applied physics. B, Lasers and optics》2009,95(3):489-495
We report an experimental investigation of the non-steady-state photoelectromotive force in nanostructured GaN within porous
glass and polypyrrole within chrysotile asbestos. The samples are illuminated by an oscillating interference pattern created
by two coherent light beams and the alternating current is detected as a response of the material. Dependences of the signal
amplitude versus temporal and spatial frequencies, light intensity, and temperature are studied for two wavelengths λ=442 and 532 nm. The conductivity of the GaN composite is measured: σ=(1.1–1.6)×10−10 Ω−1 cm−1 (λ=442 nm, I
0=0.045–0.19 W/cm2, T=293 K) and σ=(3.5–4.6)×10−10 Ω−1 cm−1 (λ=532 nm, I
0=2.3 W/cm2, T=249–388 K). The diffusion length of photocarriers in polypyrrole nanowires is also estimated: L
D=0.18 μm. 相似文献
10.
We describe a new technique to measure the UV/visible absorption spectrum of the ablated material during the laser pulse.
The technique utilizes the continuum emission from one laser produced plasma as a light source to measure the absorption properties
of a second laser produced plasma which is formed on a semi-transparent target with an array of 40 μm holes. A 6 ns, 1064
nm laser was used to ablate a Ag target and the plasma absorption was measured in the range 450–625 nm for a laser fluence
of 1 J cm−2. The total absorption cross-section is (0.5–1.5)×10−17 cm2 in the range 450–540 nm. By comparing the measured absorption with a calculation using the plasma spectroscopy code FLYCHK
it can be concluded that, in the wavelength region examined here, the absorption is mainly due to bound-bound transitions. 相似文献
11.
Yu. V. Zorenko R. M. Turchak T. I. Voznyak A. P. Luchechko 《Journal of Applied Spectroscopy》2006,73(2):211-215
By liquid-phase epitaxy from an aqueous alcoholic solution, we have obtained films of the well-known storage phospor CsBr:Eu,
and we have studied their cathodoluminescence and photoluminescence (PL) spectra compared with the undoped CsBr films. We
have established that the structure of the photoluminescence centers of the CsBr:Eu films when excited by laser radiation
in the absorption band of the Eu2+ ions (λ = 337 nm) includes Eu2+-VCs isolated dipole centers and CsEuBr3 aggregate centers, and also luminescence centers based on inclusions of hydroxyl group OH− with the corresponding emission bands in the 440 nm, 520 nm, and 600 nm regions. We have studied the dependence of the spectra
and the intensity of the photoluminescence for CsBr:Eu films on annealing temperature in air at 423–483 K, compared with analogous
dependences for CsBr:Eu single crystals obtained from the melt. We have shown that annealing the films at T = 423–463 K leads
to rapid formation of CsEuBr3 aggregate luminescence centers, while for T > 473 K thermal degradation of these centers occurs.
We conclude that the observed differences between the photoluminescence spectra of CsBr:Eu films and CsBr:Eu single crystals
may be due to additional doping of the films with OH− ions.
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Translated from Zhurnal Prikladnoi Spektroskopii, Vol. 73, No. 2, pp. 191–194, March–April, 2006. 相似文献
12.
O. V. Ovchinnikov A. B. Evlev M. A. Efimova V. G. Klyuev A. N. Latyshev A. N. Utekhin A. M. Kholkina 《Journal of Applied Spectroscopy》2005,72(6):809-813
An anti-Stokes luminescence band with λmax = 515 nm of microcrystals of solid AgCl0.95I0.05 solutions excited by a radiation flux of density 1013–1015 quanta/cm2·sec in the range 600–800 nm at 77 K was detected. It is shown that the intensity of this luminescence and the frequency of
its excitation depend on the prior UV-irradiation of samples. Analysis of the stimulated-photoluminescence spectra and the
anti-Stokes luminescence excitation spectra of the indicated microcrystals has shown that to the centers of anti-Stokes luminescence
excitation correspond local levels in the forbidden band of the crystals. These states are apparently due to the atomic and
molecular disperse silver particles that can be inherent in character or formed as a result of a low-temperature photochemical
process.
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Translated from Zhurnal Prikladnoi Spektroskopii, Vol. 72, No. 6, pp. 738–742, November–December, 2005. 相似文献
13.
IR spectra of BeSO4.4H2O and its deuterated analogue at ∼300 K and ∼110 K are reported in the region 4000–1200 cm−1 using thin film and nujol mull techniques. The observed bands have been assigned as the internal modes of the water and the
overtones and combinations of various modes using the recently revised assignments of SO4
2− and Be(aq)4 fundamentals in the region 1200–250 cm−1 (Srivastavaet al 1976). The splitting of the internal modes of water has been discussed in the light of the effects of deuteration and cooling
and it is shown that all the water molecules in a unit cell are asymmetric but crystallographically equivalent. 相似文献
14.
The IR spectrum of 4-O-methyl-2,3,6-tri-O-nitromethyl-β-D-glucopyranoside has been interpreted in detail for the first time
based on complete calculation of the normal vibration frequencies and absolute intensities of its IR absorption bands and
a comparison of them with the corresponding experimental data. The results indicate that the location of the nitrates in cellulose
nitrates can be determined experimentally from separate components of complicated absorption bands in the ranges 1700–1600
and 900–800 cm−1 of the IR spectrum.
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Translated from Zhurnal Prikladnoi Spektroskopii, Vol. 75, No. 1, pp. 43–51, January–February, 2008. 相似文献
15.
F. Kh. Tukhvatullin U. N. Tashkenbaev A. Zhumaboev Z. Mamatov 《Journal of Applied Spectroscopy》1999,66(4):501-505
The band at 896 cm−1 in the Raman spectrum of acetic acid consists of at least two lines (873 and 896 cm−1) whose intensities and depolarization factors differ strongly. A temperature increase leads to an increase in the intensity
of the 873-cm−1 line as compared to the intensity of the 896-cm−1 line. Dilution of the acid with acetonitrile leads to a similar but much more pronounced effect. In solutions with CCl4 and water, the relative intensity of the low-frequency line decreases; in aqueous solutions, the width of the 896-cm−1 line passes through a maximum with 0.4 mol. fractions of the acid (for this concentration, the line width is larger by a
factor of 2.5 than in a pure liquid), while in the solutions with CCl4 it decreases smoothly (almost twofold with strong dilution: 0.05 mol. fractions). Experimental data are in agreement with
the assumption that the 873- and 896-cm−1 lines refer to the vibrations of the same atoms in a molecule and to associates with a free and an H-bonded atom of the oxygen
of a C=O group, respectively. The difference in the frequencies and depolarization factors of the lines causes the differences
in the distribution of an electron cloud in the molecule.
To whom correspondence should be addressed.
Alisher Navoi Samarkand State University, 15, Universitetskaya Str., Samarkand, 703004, Uzbekistan. Translated from Zhurnal
Prikladnoi Spektroskopii, Vol. 66, No. 4, pp. 467–470, July–August, 1999. 相似文献
16.
Single crystals of gadolinium orthosilicate Gd2SiO5 containing 0.5 at% and 5 at% of Sm3+ were grown by the Czochralski method. Optical absorption spectra, luminescence spectra and luminescence decay curves were
recorded for these systems at 10 K and at room temperature. Comparison of optical spectra recorded in polarized light revealed
that the anisotropy of this optically biaxial host affects the intensity distribution within absorption and emission bands
related to transitions between multiplets rather than the overall band intensity. It has been found that among four bands
of luminescence related to the 4G5/2→6HJ (J=5/2–11/2) transitions of Sm3+ in the visible and near infrared region the 4G5/2 →6H7/2 one has the highest intensity with a peak emission cross section of 3.54×10−21 cm2 at 601 nm for light polarized parallel to the crystallographic axis c of the crystal. The luminescence decay curve recorded
for Gd2SiO5:0.5 at% Sm3+ follows a single exponential time dependence with a lifetime 1.74 ms, in good agreement with the 4G5/2 radiative lifetime τ
rad=1.78 ms calculated in the framework of Judd-Ofelt theory. Considerably faster and non-exponential luminescence decay recorded
for Gd2SiO5:5 at% Sm3+ sample was fitted to that predicted by the Inokuti-Hirayama theory yielding the microparameter of Sm3+–Sm3+ energy transfer C
da=1.264×10−52 cm6×s−1. 相似文献
17.
It is established that doping of CdS polycrystalline films with alkaline metals (Li, Na, K, Cs) results in an increase of
luminescence intensity by 3–5 times compared with pure films. This increase is accounted for by the placement of alkaline-metal
ions in V
Cd
2−
cation vacancies, which are nonradiative recombination centers in these films. From the dependences of the luminsecence intensity
of the doped films on the synthesis conditions (deposition temperature, concentration of doping impurities, type of doping
metal), the parameters that ensure the maximum luminescence intensity of the films are determined as Tdep ≈ 450°C and CMe = 1·10−5 at %. The luminescence intensity decreases by 1–3% upon exposure of the films to UV light (λmax = 365 nm, I = 1021 quanta·sec·cm−1) for several hours. This is indicative of the stability of these films against UV radiation.
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Translated from Zhurnal Prikladnoi Spektroskopii Vol. 74, No. 3, pp. 362–366, May–June, 2007. 相似文献
18.
The preparation of pyridine functionalized TbF3 nanoparticles are described in this report. Synthesized nanoparticles were characterized using the TEM, UV/Vis, FTIR and
photoluminescence spectroscopy. TEM micrograph reveals the nanorod shaped, uniform in size with a particles size in the range
of 20–30 nm. FTIR spectrum shown characteristic absorption bands of pyridine and a small intensity band at 411 cm−1 corresponding metal nitrogen ν(Tb–N) bonding. Uv-vis spectrum shown the characteristic absorption transitions of Tb3+ ion. A strong emission transition at 540 nm (5D4 → 7F5) was observed on excite by visible light at 414 nm. 相似文献
19.
Vacuum-deposited perylene-3,4,9,10-tetracarboxylic acid dianhydride thin films are investigated by IR-spectropolarimetry with
variable incident angle of plane-polarized radiation. Anisotropy of absorption bands in the region 700–900 cm−1 is detected. Absorption bands in the subregions 728–736 and 806–810 cm−1 are shown to be of triplet nature with orthogonally oriented dipole moments within the triplet. 相似文献
20.
H. Hobert H.H. Dunken G. Peiter W. Stier M. Diegel H. Stafast 《Applied Physics A: Materials Science & Processing》1999,69(1):69-76
A large number of thin SiC films, prepared at different conditions by KrF excimer laser ablation of solid SiC targets and
deposition onto Si substrates (some onto quartz glass (QG) and yttrium-stabilized zirconia (YSZ)) were characterized by infrared
and Raman spectroscopy. The films consisted of nano- and microcrystalline SiC and contained nanocrystalline carbon in the
case of QG or YSZ substrates. Raman spectra of nanocrystalline SiC (grains <30 nm) reflect the phonon density-of-state function
of SiC by broad scattering effects at 220–600 and 650–950 cm−1. Medium-size crystallites are represented by a relatively narrow asymmetric band at 790 cm−1 and crystallites >200 nm by an additional asymmetric band at 960 cm−1. Small satellite bands at 760 and 940 cm−1, attributed to SiC surface layers, were resolved in some well-ordered samples. Optical modelling was needed to interpret
the IR spectra. SiC films could be represented by an effective medium model containing a SiC host phase and embedded particles
with free charge carriers. The crystalline order of SiC films can be estimated from the parameters of the SiC oscillators.
Received: 5 October 1998 / Accepted: 8 January 1999 / Published online: 5 May 1999 相似文献