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1.
Infrared spectra of brassinolide and castasterone steroid phytohormones and their 24-epi derivatives
Absorption bands in IR spectra of brassinolide, castasterone, and their 24-epi derivatives in the frequency range 3800–1000
cm–1 have been interpreted. A number of spectral features distinguishing brassinolide from castasterone have been found. The conducted
analysis shows that the structural differences manifest themselves in IR spectra of the investigated brassinosteroids in the
region of stretching vibrations of CO–H, C=O, C–OH, C–O–C, CH3, CH2, and CH groups. The main distinctions in IR spectra of brassinolides and castasterones are due to the B ring structure. 相似文献
2.
G. B. Tolstorozhev I. V. Skornyakov V. I. Pekhnio A. N. Kozachkova N. I. Sharykina 《Journal of Applied Spectroscopy》2012,79(3):453-458
We have used Fourier transform IR spectroscopy methods to study normal mouse lung tissue and also after subcutaneous transplantation
of a B-16 melanoma tumor in the tissue. We also studied tissues with B-16 melanoma after they were treated with coordination
compounds based on palladium complexes of methylenediphosphonic acid. The IR spectra of the lung tissues with metastases in
the region of the C = O stretching vibrations are different from the IR spectra of normal tissue. We identified spectroscopic
signs of the presence of metastases in the lung. We show that when a cancerous tumor is treated with a preparation of palladium
complexes of methylenediphosphonic acid, the spectroscopic signs of the presence of metastases in the lung are missing. After
treatment with the optimal dose of this drug, the IR spectrum of the lung tissue in which multiple metastases were present
before treatment corresponds to the spectrum of normal tissue. We have determined the efficacy of the antitumor activity of
coordination compounds based on palladium complexes of methylenediphosphonic acid. 相似文献
3.
M. A. Algatti R. P. Mota R. Y. Honda M. E. Kayama K. G. Kostov R. S. Fernandes T. C.A.M. Azevedo N. C. Cruz 《The European Physical Journal D - Atomic, Molecular, Optical and Plasma Physics》2009,54(2):325-328
This paper deals with plasma polymerization processes of diethylene glycol dimethyl ether. Plasmas were produced at 150 mtorr
in the range of 10 W to 40 W of RF power. Films were grown on silicon and quartz substrates. Molecular structure of plasma
polymerized films and their optical properties were analyzed by Fourier transform infrared spectroscopy (FTIR) and ultraviolet-visible
spectroscopy. The IR spectra show C–H stretching at 3000–2900 cm-1, C=O stretching at 1730–1650 cm-1, C–H bending at 1440–1380 cm-1, C–O and C–O–C stretching at 1200–1000 cm-1. The concentrations of C–H, C–O and C–O–C were investigated for different values of RF power. It can be seen that the C–H
concentration increases from 0.55 to 1.0 au (arbitrary unit) with the increase of RF power from 10 to 40 W. The concentration
of C–O and C–O–C decreases from 1.0 to 0.5 au in the same range of RF power. The refraction index increased from 1.47 to 1.61
with the increase of RF power. The optical gap calculated from absorption coefficient decreased from 5.15 to 3.35 eV with
the increase of power. Due to its optical and hydrophilic characteristics these films can be applied, for instance, as glass
lens coatings for ophthalmic applications. 相似文献
4.
A systematic study of the chemical bonding in hydrogenated amorphous germanium–carbon (a-Ge1-xCx:H)alloys using X-ray photoelectron spectroscopy (XPS) is presented. The films, with carbon content ranging from 0 at. % to
100 at. %, were prepared by the rf co-sputtering technique. Raman spectroscopy was used to investigate the carbon hybridization.
Rutherford backscattering spectroscopy (RBS) and XPS were used to determine the film stoichiometry. The Ge 3d and C 1s core
levels were used for investigating the bonding properties of germanium and carbon atoms, respectively. The relative concentrations
of C–Ge, C–C, and C–H bonds were calculated using the intensities of the chemically shifted C 1s components. It was observed
that the carbon atoms enter the germanium network with different hybridization, which depends on the carbon concentration.
For concentrations lower than 20 at. %, the carbon atoms are preferentially sp3 hybridized, and approximately randomly distributed. As the carbon content increases the concentration of sp2 sites also increases and the films are more graphitic-like.
Received: 4 May 1999 / Accepted: 24 November 1999 / Published online: 24 March 2000 相似文献
5.
We used infrared spectroscopy methods to study the molecular structure of tissues from human organs removed during surgery.
The IR spectra of the surgical material from breast, thyroid, and lung are compared with data from histological examination.
We show that in malignant neoplasms, a change occurs in the hydrogen bonds of protein macromolecules found in the tissue of
the studied organs. We identify the spectral signs of malignant pathology.
__________
Translated from Zhurnal Prikladnoi Spektroskopii, Vol. 75, No. 3, pp. 395–399, May–June, 2008. 相似文献
6.
IR spectra of acetonitrile embedded in an argon matrix and in a liquid are recorded. IR spectra of specimens obtained with
different concentrations of acetonitrile in argon are analyzed. The spectral region of C≡N vibrations of 2200–2300 cm−1 with bands of monomers and possible associates is investigated. Overlap with the band of a hot transition on the low-frequency
side is responsible for the pronounced asymmetry of the band ν(C≡N).
To whom correspondence should be addressed.
St. Petersburg State Institute of Precision Mechanics and Optics (Technical University), 14, Sablinskaya Str., St. Petersburg,
197101, Russia. Translated from Zhurnal Prikladnoi Spektroskopii, Vol. 66, No. 5, pp. 627–631, September–October, 1999. 相似文献
7.
Modern problems in the diagnosis of oncological pathologies using spectroscopic methods of analysis are considered. Fourier-transform
IR spectroscopy methods are illustrated by investigation of tissues of breast, thyroid gland, stomach, kidney, lung, and skin
excised during surgical intervention. IR spectra of surgical material are compared with data of histological analysis. Spectra
of proteins and lipids in malignant neoplasms differ from those in benign tumors and in tissues beyond the pathological focus.
Differences in protein spectra are attributed to changes in the supramolecular structure due to cleavage of intramolecular
C=OH–N hydrogen bonds. Differences in IR spectra of lipids in neoplasms, when compared with those in normal tissues, are caused
by changes in the structure of side chains of fatty-acid radicals appearing in malignant tumors. Spectral signatures of malignant
pathology are revealed. 相似文献
8.
IR spectroscopy methods have been adopted for investigating resected tissues of mammary glands. IR spectra of surgical material
are compared with histological data. Spectra of proteins and lipids in malignant tumors are shown to be different from those
in benign tumors and in tissues outside the pathologically impacted volume. Differences in the protein spectra are due to
changes in the supramolecular structure because of the cleavage of intramolecular C=O⋅⋅⋅H–N H-bonds. Spectral signatures of
malignant pathologies are identified.
Translated from Zhurnal Prikladnoi Spektroskopii, Vol. 76, No. 2, pp. 261–266, March–April, 2009. 相似文献
9.
C. Moreau E. Therssen P. Desgroux J.F. Pauwels A. Chapput M. Barj 《Applied physics. B, Lasers and optics》2003,76(5):597-602
The potential of Laser Induced Fluorescence detection of the CH radical using C–X (0–0) excitation is investigated in a sooting
methane/air diffusion flame at atmospheric pressure. Fluorescence is detected using the very narrow (<0.4 nm) Q-branch of
the C–X (0–0) band, which enables the measurement of CH in sooting flames without interference from PAH fluorescence and soot
emissions. Absolute concentrations are obtained using Cavity Ring Down Spectroscopy. 1D CH profiles in the sooting zone are
recorded using a CCD camera with an excellent signal-to-noise ratio. The C–X (0–0) excitation associated with Q-branch detection
is shown to be three times more efficient than the B–X scheme.
Received: 4 March 2002 / Revised version: 5 November 2002 / Published online: 5 May 2003
RID="*"
ID="*"Corresponding author. Fax: +33-3/2033-6463, E-mail: eric.therssen@univ-lille1.fr 相似文献
10.
I. I. Polovinko S. V. Rykhlyuk V. B. Koman I. D. Karbovnyk 《Journal of Applied Spectroscopy》2009,76(1):116-120
We propose a new method for obtaining K2Co
x
Ni1–x
(SO4)2⋅6H2O (x = 0, 0.4, 0.8, 1) crystals, involving the use of the chlorides (CoCl2⋅6H2O and NiCl2⋅6H2O) in an aqueous solution instead of the widely used sulfates. We have studied the transmission spectra of the grown single
crystals in the range λ = 200–900 nm and the IR reflectance spectra in the 2.5–20 μm region. We have observed a change in
the position and intensity of the absorption bands as a function of the composition of the crystals. Based on the Tanabe–Sugano
diagrams, we determined the crystal field splitting (Dq) and its dependence on the nickel concentration.
Translated from Zhurnal Prikladnoi Spektroskopii, Vol. 76, No. 1, pp. 126–130, January–February, 2009. 相似文献
11.
The size effect of silver nanoparticles on photophysical properties of 2,3-bis(chloromethyl)anthracene-1,4,9,10-tetraone (BCMAT) has been investigated using an IR technique. Silver colloids of different sizes have been prepared by two different methods. Mechanisms for adsorption and complex formation have been elucidated from surface-enhanced infrared absorption spectra. The observation shows that BCMAT is adsorbed on silver nanoparticles through a C = O group and that its orientation is stand-on. Surface enhancement factors have been calculated. As the particles decrease in size their total surface area grows, which leads to the gain in the enhancement factor. 相似文献
12.
Dilip C. D. Nath Veena Sahajwalla 《Applied Physics A: Materials Science & Processing》2011,104(2):539-544
We produced carbon nanotubes (CNTs) by pyrolysis of a composite film of poly (vinyl alcohol) (PVA) with fly ash (FA) at 500°C
for 10 min under nitrogen. The composite films were prepared by a suspension of PVA and FA in deionized water and cast onto
glass petri dishes. The morphologies of the CNTs were observed in the images of scanning and transmission electron microscopy,
showing different types of structures, e.g. whiskers, branches, ropes and graphene sheets. The widths of the CNTs measured
varied in the range 18–80 nm. X-ray photoelectron spectroscopy analysis showed five types of carbon binding peaks, C–C/C–H
(∼77%), C–O–H (∼9%), –C–O–C (∼5%), C=O (∼5%) and –O–C=O (∼3%). From an image of a broken CNT, a mechanism was proposed for
the formation of CNTs. The CNTs grown on FA surfaces have potential for the fabrication of high-strength composite materials
with polymer and metal. 相似文献
13.
Infrared (IR) and UV spectra of ternary Li2O–CuO–P2O5 glasses in two series Li2O(65−X)%–CuO(X%)–P2O5(35%), X = 20, 30, 40 and Li2O(55−X)%–CuO(X%)–P2O5(45%), X = (10, 20, 30) were studied. Infrared (IR) investigations showed the metaphosphate and pyrophosphate structures and with
increase of CuO content in metaphosphate glass, the skeleton of metaphosphate chains is gradually broken into short phosphate
groups such as pyrophosphate. IR spectra showed one band at about 1,220 and 1,260 cm−1 for P2O5(35%) and P2O5(45%) series, respectively, assigned to P=O bonds. For CuO additions ≤20 mol%, the glasses exhibit two bands in the frequency
range 780–720 cm−1 which are attributed to the presence of two P–O–P bridges in metaphosphate chain. But for CuO addition ≥30 mol%, the glasses
exhibit only a single band at 760 cm−1 which is assigned to the P–O–P linkage in pyrophosphate group. In optical investigations, absorption coefficient versus photon
energy showed three regions: low energy side, Urbach absorption, and high energy side. In Urbach’s region, absorption coefficient
depends exponentially on the photon energy. At high energy region, optical gap was calculated and investigations showed indirect
transition in compounds and decreases in optical gap with increases of copper oxides contents that is because of electronic
transitions and increasing of nonbridging oxygen content. 相似文献
14.
K. J. Öberg 《The European Physical Journal D - Atomic, Molecular, Optical and Plasma Physics》2007,41(1):25-47
Transition isotope shifts of 3s–3p transitions in Ne II and Ne III are measured in Fourier transform spectra from a hollow-cathode
source. Accurate absolute line-center positions of the 20Ne isotope are derived for the purpose of tertiary wavelength standards in the region 2000–5000 ?. A robust statistical treatment
is applied, yielding line-position uncertainties that are lower than for the Ar II secondary standards used as references.
The influence of Stark shifts on both the new Ne II standards and the Ar II standards is also investigated. In addition, improved
wavenumbers of the 3p–3d and 3p–4s transitions are presented, of which 12 in Ne II have been measured for the first time.
Electronic supplementary material Supplementary Online Material 相似文献
15.
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.
__________
Translated from Zhurnal Prikladnoi Spektroskopii, Vol. 73, No. 1, pp. 106–112, January–February, 2006. 相似文献
16.
We used infrared spectroscopy methods to study thyroid tumor tissues removed during surgery. The IR spectra of the surgical
material are compared with data from histological examination. We show that in malignant neoplasms, the spectra of proteins
in the region of C=O vibrations are different from the spectra of these substances in benign tumors and in tissues outside
the pathological focus at a distance >1 cm from the margin of the tumor. The differences in the spectra are due to changes
in the supermolecular structure of the proteins, resulting from rearrangement of the system of hydrogen bonds. We identify
the spectral signs of malignant pathologies. 相似文献
17.
This paper describes the preparation and conductivity studies of polyindole–ZnO composite polymer electrolyte (CPE) with LiClO4. Polyindole–ZnO-based polymer nanocomposites were prepared by chemical method and characterized by XRD, infrared (IR), scanning
electron microscope (SEM), transmission electron microscopy (TEM), and thermogravimetric analysis (TGA). The IR spectrum confirms
the intermolecular interaction between polyindole and ZnO. The significant spectral changes of polyindole and ZnO nancomposites
reveal the strong interaction between polyindole and ZnO nanoparticles. The structural morphologies of the ZnO, polyindole,
and polyindole–ZnO are obtained from SEM. The TEM image of polyindole nanocomposite shows that ZnO is embedded in polyindole
matrix. An enhanced conductivity of 4.405 × 10−7 S cm−1 at 50 °C for the CPE was determined from impedance studies. 相似文献
18.
Nobumitsu Sakai Masato Takakura Harutoshi Imamura Miki Sugimoto Yasuto Matsui Hirokazu Miyoshi Aki Nakayama Minoru Yoneda 《Journal of nanoparticle research》2012,14(5):849
We analyzed the whole-body distribution of 14C–ADP-labeled silica nanoparticles (14C–ADP–SiO2 nanoparticles) and submicron particles (14C–ADP–SiO2 submicron particles) after intravenous injection into ICR mice. The 14C–ADP–SiO2 nanoparticles and submicron particles were synthesized before the injection and the particle size was 19.6 and 130 nm, respectively.
Similarly, the shape was spherical and the crystallinity was amorphous. After the synthesis, we injected mice with the 14C–ADP–SiO2 nanoparticles or the 14C–ADP–SiO2 submicron particles and dissected tissues after 1, 2, 4, 8 and 24 h. The radioactivity in the tissues was measured with a
liquid scintillation counter. As a result, the retention percentage in bone, skin, lymph nodes, and the digestive mixture
was at least twofold higher in the 14C–ADP–SiO2 nanoparticles-exposed mice, whereas the retention percentage in the kidney was statistically higher in the 14C–ADP–SiO2 submicron particles-exposed mice. Both types of 14C–ADP–SiO2 particles mainly translocated to the muscle, bone, skin, and liver, but hardly translocated to the brain and olfactory bulb.
Furthermore, the 14C–ADP–SiO2 nanoparticles had a higher retention percentage (62.4 %) in the entire body at 24-h post-injection than did the 14C–ADP–SiO2 submicron particles (50.7 %). Therefore, we suggested that the 14C–ADP–SiO2 nanoparticles might be more likely than the 14C–ADP–SiO2 submicron particles to be retained in the body, and consequently they might be gradually accumulated by chronic exposure. 相似文献
19.
Kh. Sh. Abdulov 《Journal of Applied Spectroscopy》2008,75(4):494-499
Polarized IR spectra for two conformations of trans-1,4-polyisoprene (α-and β-gutta-percha) were calculated. The IR dichroism
of the absorption bands was calculated for both conformations. The computed results for polarized IR spectra and IR dichroism
agree reasonably well with the respective experiment data.
__________
Translated from Zhurnal Prikladnoi Spektroskopii, Vol. 75, No. 4, pp. 470–475, July–August, 2008. 相似文献
20.
N. A. Nemkovich H. Detert V. Schmitt Yu. V. Kruchenok 《Journal of Applied Spectroscopy》2012,79(3):353-359
Absorption and fluorescence spectra of octupolar centrosymmetric oligophenylenevinylene dyes (E,E)-bis[2-(4-hexyloxyphenyl)ethenyl]-(E,E)-3,6-bis-[2-(4-N,N-dipropylaminophenyl)ethenyl]pyrazine and (E,E,E,E)-2,3,5,6- tetra-[2-(4-hexyloxyphenyl)ethenyl]pyrazine were measured in various solvents. An electro-optical absorption method was used to determine their dipole moments as μ g = 6.1∙10–30 and 3.4∙10–30 C∙m in the equilibrium ground state and the increased values ∆ a μ = 11.9∙10–30 and 8.2∙10–30 C∙m upon excitation into a Franck–Condon state. Quantum-chemical calculations showed that the molecules had non-planar configurations. The π,π-conjugated system was localized on the most planar part of the molecule that was responsible for light absorption in the range 300–450 nm due to a change in the geometry of the molecules in the ground state. Localized excitation of the molecules caused their dipole moments ∆ a μ to change significantly. 相似文献