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1.
M. V. Galkin Ye. V. Ageeva D. A. Nedosekin M. A. Proskurnin A. Yu. Olenin G. M. Mokrousov 《Moscow University Chemistry Bulletin》2010,65(2):91-97
Thermal lens spectrometry is applied to determine the absorption of transparent nanocomposite materials, which are produced
by the thermal decomposition of silver salts absorbed in the bulk of a polymethacrylate matrix. The high spatial resolution
of determination, corresponding to the size of laser beams, makes it possible to evaluate the homogeneity for the distribution
of coloration in the matrix. The advantages of thermal lens spectrometry over spectrophotometry include the weak effect of
sample scattering on the results of its absorption determination and a higher sensitivity of determination, which may exceed
that of spectrophotometry by one or two orders of magnitude. The possibility of achieving local syntheses of nanosized particles
in the bulk of the matrix by virtue of the photoinduced decomposition of silver salts in initial polyacrylate materials is
shown. Thermal lens experiments also allow the combination of the synthesis of silver nanoparticles and control of the absorbance
for the prepared structural units. 相似文献
2.
A. P. Kouzov V. B. Morozov S. A. Mochalov A. N. Olenin V. G. Tunkin 《Optics and Spectroscopy》2002,92(5):685-689
By using the method of nonstationary spectroscopy of coherent anti-Stokes Raman scattering, pulsed responses of the Q band of the vibrational-rotational transition in the CO2 molecule at a frequency of 1285 cm?1 are measured under conditions of broadening close to the Doppler type. The ratios of the amplitudes of Q-band components at known frequencies are obtained by fitting to the measured pulsed responses. 相似文献
3.
Russian Journal of General Chemistry - This review deals with one of the most important classes of nanomaterials — oxide nanoparticles. Preparative methods for the synthesis of nanooxides,... 相似文献
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5.
V. G. Arakcheev V. N. Bagratashvili A. A. Valeev V. B. Morozov A. N. Olenin V. K. Popov D. V. Yakovlev 《Russian Journal of Physical Chemistry B, Focus on Physics》2009,3(7):1062-1066
Coherent anti-Stokes Raman scattering spectra measured within the Q-branch of the vibrational transition ν1 are used to gain insights into the state of carbon dioxide molecules in nanopores of Vycor™ glass at room temperature (20.5°C)
and a subcritical temperature of 30.5°C and gas pressures up to the saturation point P
sat for each temperature. Along with the main spectral component, belonging to gaseous CO2 molecules, the spectra recorded at pressures close to P
sat feature a second (low-frequency) component. The second component is associated with the contribution from the CO2 molecules trapped inside pores. A spectral deconvolution with account for the interference of these two bands makes it possible
to estimate the spectral characteristics of the second (low-frequency) component at each temperature. At 20.5°C, the bandwidth
of the low-frequency component decreases with CO2 pressure, a behavior that can be explained by the transition of CO2 from the adsorbed to the condensed state in the pore. At the subcritical temperature of 30.5°C, the spectral width of the
second component is pressure-independent and close to the value measured in the bulk of the supercritical fluid, a result
likely associated with a low-temperature shift of the critical point of the substance trapped in nanopores. 相似文献
6.
Papers dealing with chemical modification of the surface of noble metal nanoparticles and their use in analytical and bioanalytical chemistry, pharmacology, etc., are analyzed. Grafting of a layer of preset chemical composition on the nanoparticle surface allows preparation of functional materials combining the properties of the metal core (surface plasmon resonance, enhancement of fluorescence and nonelastic scattering) and shell (selective interaction with components of the surrounding medium). Combination of these properties opens wide prospects for using the modified nanoparticles in various branches of science and engineering, primary in chemical and biochemical analysis, and also in pharmacology. 相似文献
7.
Yu.A. Krutyakov A.A. Kudrinsky A.Yu. Olenin G.V. Lisichkin 《Applied Surface Science》2010,256(23):7037-7042
A simple technique was developed for the synthesis of silver nanoparticles (NPs) in an aqueous medium using water soluble sulfonated polyaniline as a new non-covalent effective stabilizer. The narrow size distribution of the NPs was achieved through the synthesis. In neutral and basic solutions the as-prepared silver NPs demonstrated resistance toward aggregation over several months and at least a few days at pH 1. The versatility of the procedure was demonstrated also for the preparation of gold nanoparticles. Transmission electron microscopy with electron microdiffraction, UV-vis spectroscopy, XRD, XPS and FTIR analyses were used to characterize the structure and chemical composition of as obtained silver NPs. 相似文献
8.
A. Yu. Olenin G. I. Romanovskaya Yu. A. Krutyakov S. Yu. Vasil’eva A. A. Kudrinskii G. V. Lisichkin 《Journal of Analytical Chemistry》2009,64(1):26-30
A procedure was developed for the synthesis of hydrophobic silver nanoparticles with an average size of 4 nm in two-phase water-organic emulsions. The physical properties of the obtained silver organosol were studied by molecular spectroscopy and electron microscopy. It was found that the synthesized silver nanoparticles had a specific surface of 60–110 m2/g. It was shown that chemically modified silver nanoparticles can be used as an adsorbent for preconcentrating polycyclic aromatic hydrocarbons (using pyrene as an example) from dilute n-hexane solutions followed by luminescence determination at room temperature. 相似文献
9.
A nonenzymatic method was developed for the detection and quantification of hydrogen peroxide using metallic sols obtained by the reduction of silver compounds with sodium borohydride in the presence of a surface stabilizer. These sols changed color on exposure to aqueous solutions of hydrogen peroxide. The nature of the stabilizer used in sol preparation affects spectral characteristics of the final product formed in the reaction with hydrogen peroxide. In the case of polyvinyl pyrrolidone, the intensity of the surface plasmon resosnance absorption band at 405 nm decreased. In using cetyltrimethylammonium bromide, a signal at 519 nm appeared along with the similar decrease in the absorption band at 408 nm. The band intensity depends on the concentration of hydrogen peroxide. The described phenomena can form a basis for the development of procedures for the qualitative and quantitative determination of hydrogen peroxide in water bodies. 相似文献
10.
D. B. Furman A. O. Ivanov A. Yu. Olenin A. Yu. Belyankin A. V. Ignatenko V. S. Bogdanov G. V. Lisichkin . V. Bragin 《Russian Chemical Bulletin》1989,38(12):2447-2451
-Bis(diphenylphosphine)aminopropyltriethoxysilane is synthesized and studied by IR and1H,13C, and31P1H NMR spectroscopies for the first time. Chemical modification of silica with (EtO)3Si(CH2)3N(PPh2)2 gives the support (-DPAMPS) containing identical N(PPh2)2 ligands on its surface. Subsequent treatment of the support with (EtO)3Si(CH2)3NH2 and ClPPh2 gives a silica surface containing two types of attached ligands, NH2 and N(PPh2)2, in the ratio 11. The heterogenized complexes Ni-HMC, prepared by ligand exchange between Ni(PPh3)n (n=3, 4) and -DPAMPS, in combination with Et2AlCl exhibit activity and selectivity for ethylene dimerization.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 12, pp. 2674–2678, December, 1989. 相似文献