Главная
Авторизация
Фамилия
Пароль
 

Базы данных


Труды сотрудников ИБФ СО РАН - результаты поиска

Вид поиска

Область поиска
в найденном
 Найдено в других БД:Каталог книг и продолжающихся изданий библиотеки Института биофизики СО РАН (1)
Формат представления найденных документов:
полный информационныйкраткий
Отсортировать найденные документы по:
авторузаглавиюгоду изданиятипу документа
Поисковый запрос: (<.>K=film<.>)
Общее количество найденных документов : 25
Показаны документы с 1 по 20
 1-20    21-25 
1.

Вид документа : Статья из журнала
Шифр издания :
Автор(ы) : Peng J.L., Bulcock S..., Belobrov P.I., Bursill L.A.
Заглавие : Surface bonding states of nano-crystalline diamond balls
Колич.характеристики :15 с
Место публикации : Int. J. Mod. Phys. B: WORLD SCIENTIFIC PUBL CO PTE LTD, 2001. - Vol. 15, Is. 31. - P4071-4085. - ISSN 0217-9792, DOI 10.1142/S0217979201007865
Примечания : Cited References: 20
Предметные рубрики: PLASMON RESPONSE
POWDER
SPECTROSCOPY
MICROSCOPY
SILICON
SI(111)
Аннотация: The rough surface of nano-crystalline diamond spheres induces surface electronic states which appear as a broadened pre-peak over approx. 15 eV at the C K-edge energy threshold for carbon in the parallel electron energy loss spectrum (PEELS). This appears to be at least partially due to 1s-pi* transitions, although typically the latter occupy a range of only 4 eV for the sp(2) edge of highly-oriented pyrollytic graphite (HOPG). No pi* electrons appear in the conduction band inside the diamond particles, where all electrons are sp(3) hybridized. PEELS data were also obtained from a chemical vapour deposited diamond film (CVDF) and gem-quality diamond for comparison with the spectra of nano-diamonds. The density of sp(2) and sp(3) states on the surface of diamond nano-crystals is calculated for simple structural models of the diamond balls, including some conjecture about surface structures. The results are used to interpret the sp(2)/sp(3) ratios measured from the PEELS spectra recorded as scans across the particles. Surface roughness at the atomic scale was also examined using high-resolution transmission electron microscopy (HRTEM) and electron nano-diffraction patterns were used to confirm the crystal structures.
WOS
Найти похожие
2.

Вид документа : Статья из журнала
Шифр издания :
Автор(ы) : Sushchik N.N., Kalacheva G.S., Gladyshev M.I.
Заглавие : Secretion of free fatty acids by prokaryotic and eukaryotic algae at optimal, supraoptimal, and suboptimal growth temperatures
Колич.характеристики :6 с
Место публикации : Microbiology: MAIK NAUKA/INTERPERIODICA, 2001. - Vol. 70, Is. 5. - P542-547. - ISSN 0026-2617, DOI 10.1023/A:1012351920589
Примечания : Cited References: 19
Предметные рубрики: SURFACE-FILM
WATER
Ключевые слова (''Своб.индексиров.''): free fatty acids--secretion--microalgae
Аннотация: The paper describes the composition of extracellular free fatty acids (FFAs) and intracellular fatty acids (FAs) in the enrichment cultures of the prokaryotic alga Spirulina platensis and the eukaryotic alga Chlorella vulgaris grown at optimal, supraoptimal, and suboptimal growth temperatures. With increasing growth temperature, the degree of unsaturation of the intracellular FAs of both algae decreased, while that of the extracellular FFAs of S. platensis increased. The composition of the extracellular FFAs of C vulgaris practically did not depend on the growth temperature.
WOS
Найти похожие
3.

Вид документа : Статья из журнала
Шифр издания :
Автор(ы) : Sushchik N.N., Kalacheva G.S., Zhila N.O., Gladyshev M.I., Volova T.G.
Заглавие : A temperature dependence of the intra- and extracellular fatty-acid composition of green algae and cyanobacterium
Колич.характеристики :7 с
Место публикации : Russ. J. Plant Physiol.: MAIK NAUKA/INTERPERIODICA, 2003. - Vol. 50, Is. 3. - P374-380. - ISSN 1021-4437, DOI 10.1023/A:1023830405898
Примечания : Cited References: 31
Предметные рубрики: SURFACE-FILM
LIPIDS
WATER
BLOOM
SEA
BAY
Ключевые слова (''Своб.индексиров.''): green algae--cyanobacterium--lipids--fatty acids--secretion
Аннотация: The effect of ambient temperature on the composition of intracellular fatty acids and the release of free fatty acids (FFA) into a medium by cyanobacterium Spirulina platensis and eukaryotic microalgae, Chlorella vulgaris and Botryococcus braunii, was studied using their batch cultures. It was found that all the species studied, regardless of their taxonomic status, responded to the temperature regime by similar changes in their intracellular fatty acid composition: the relative content of more unsaturated fatty acids decreased with the elevation of temperature. At the same time, in the prokaryote, this temperature shift blocked, first of all, the elongation of 16:0 to 18:0 and then their further desaturation. In eukaryotes, the change in the desaturation of dienoic to trienoic fatty acids was the most pronounced process. The ratio of dienoic to trienoic fatty acids remained almost unchanged in S. platensis. The relative content of extracellular unsaturated FFA increased in the prokaryotic organism S. platensis at a higher temperature. But no significant changes in the composition of extracellular unsaturated FFA were detected in eukaryotic algae upon temperature elevation.
WOS
Найти похожие
4.

Вид документа : Статья из журнала
Шифр издания :
Автор(ы) : Gladyshev M.I., Sushchik N.N., Kalacheva G.S., Shchur L.A.
Заглавие : Composition of free fatty acids of the surface film of water and kinetic of self-purification from phenol in forest pond at ''bloom'' of Volvox aureus
Колич.характеристики :4 с
Место публикации : Dokl. Akad. Nauk: MEZHDUNARODNAYA KNIGA, 1996. - Vol. 349, Is. 6. - С. 840-843. - ISSN 0869-5652
Примечания : Cited References: 5
Предметные рубрики: KRASNOYARSK RESERVOIR
MODELS
Найти похожие
5.

Вид документа : Статья из журнала
Шифр издания :
Автор(ы) : Volova T., Kiselev E., Vinogradova O., Nikolaeva E., Chistyakov A., Sukovatiy A., Shishatskaya E.
Заглавие : A glucose-utilizing strain, cupriavidus euthrophus B-10646: Growth kinetics, characterization and synthesis of multicomponent PHAs
Место публикации : PLoS ONE. - 2014. - Vol. 9, Is. 2. - ISSN 19326203 (ISSN) , DOI 10.1371/journal.pone.0087551
Ключевые слова (''Своб.индексиров.''): 3 hydroxybutyrate 3 hydroxyhexanoate 3 hydroxyvalerate copolymer--3 hydroxybutyrate 4 hydroxybutyrate 3 hydroxyvalerate copolymer--copolymer--gamma butyrolactone--glucose--hexanoic acid--poly(3 hydroxybutyric acid)--polyhydroxyalkanoic acid--polystyrene--propionic acid--unclassified drug--valeric acid--animal cell--article--bacterial growth--bacterium culture--cell adhesion--cell proliferation--crystal structure--culture optimization--cupriavidus--cupriavidus euthrophus--decomposition--elasticity--film--glucose utilization--kinetics--mechanics--melting point--mouse--nonhuman--nucleotide sequence--physical chemistry--polymerization--strength--synthesis
Аннотация: This study investigates kinetic and production parameters of a glucose-utilizing bacterial strain, C. eutrophus B-10646, and its ability to synthesize PHA terpolymers. Optimization of a number of parameters of bacterial culture (cell concentration in the inoculum, physiological activity of the inoculum, determined by the initial intracellular polymer content, and glucose concentration in the culture medium during cultivation) provided cell concentrations and PHA yields reaching 110 g/L and 80%, respectively, under two-stage batch culture conditions. Addition of precursor substrates (valerate, hexanoate, propionate, ?-butyrolactone) to the culture medium enabled synthesis of PHA terpolymers, P(3HB/3HV/4HB) and P(3HB/ 3HV/3HHx), with different composition and different molar fractions of 3HB, 3HV, 4HB, and 3HHx. Different types of PHA terpolymers synthesized by C. eutrophus B-10646 were used to prepare films, whose physicochemical and physical-mechanical properties were investigated. The properties of PHA terpolymers were significantly different from those of the P3HB homopolymer: they had much lower degrees of crystallinity and lower melting points and thermal decomposition temperatures, with the difference between these temperatures remaining practically unchanged. Films prepared from all PHA terpolymers had higher mechanical strength and elasticity than P3HB films. In spite of dissimilar surface structures, all films prepared from PHA terpolymers facilitated attachment and proliferation of mouse fibroblast NIH 3T3 cells more effectively than polystyrene and the highly crystalline P3HB. Copyright: © 2014 Volova et al.
Scopus
Найти похожие
6.

Вид документа : Статья из журнала
Шифр издания :
Автор(ы) : Gladyshev M.I., Levin L.A., Sushchik N.N.
Заглавие : The influence of a monolayer of an aliphatic acid on the oscillation of the temperature in the surface layer of water
Колич.характеристики :3 с
Место публикации : Izv. Akad. Nauk. Fiz. Atmos. Okean. Biol.: MEZHDUNARODNAYA KNIGA, 1996. - Vol. 32, Is. 3. - P410-412. - ISSN 0002-3515
Примечания : Cited References: 13
Предметные рубрики: VELOCITY
Аннотация: The influence of a monolayer of a palmitic acid on amplitude-frequency characteristics of temperature oscillations caused by thermal spots of a surface film was experimentally determined in a Langmuir tank. An analysis of the power spectra the temperature oscillations were multimodal. In addition, no consistant differences between the spectrum for a pure surface and the spectrum for a surface covered by-an acid monolayer were found. A roughened gain-frequency factor was found that is equal to the ratio of the average period between the thermal spots to the dispersion of the time series of temperature oscillations. The factor significantly differed over a wide range of temperatures for a pure surface and for a surface covered with the monolayer. The experimental results do not confirm the existence of a leading frequency in the temperature oscillations of a cold surface film due to an appearance of thermal spots.
WOS
Найти похожие
7.

Вид документа : Статья из журнала
Шифр издания :
Автор(ы) : Ismagilov, Rinat, Malykhin, Sergei, Puzyr, Aleksey, Loginov, Artem, Kleshch, Victor, Obraztsov, Alexander
Заглавие : Single-Crystal Diamond Needle Fabrication Using Hot-Filament Chemical Vapor Deposition
Колич.характеристики :9 с
Коллективы : Russian Science FoundationRussian Science Foundation (RSF) [19-79-00203]; Russian Foundation for Basic ResearchRussian Foundation for Basic Research (RFBR) [18-29-19071]
Место публикации : Materials: MDPI, 2021. - Vol. 14, Is. 9. - Ст.2320. - ISSN 1996-1944(eISSN), DOI 10.3390/ma14092320
Примечания : Cited References:32. - This work was supported by the Russian Science Foundation (project no. 19-79-00203) and by the Russian Foundation for Basic Research (grant no. 18-29-19071, in part for PL and Raman inspection).
Аннотация: Single-crystal diamonds in the form of micrometer-scale pyramids were produced using a combination of hot-filament (HF) chemical vapor deposition (CVD) and thermal oxidation processes. The diamond pyramids were compared here with similar ones that were manufactured using plasma-enhanced (PE) CVD. The similarities revealed in the morphology, Raman, and photoluminescent characteristics of the needles obtained using the hot-filament and plasma-enhanced CVD are discussed in connection with the diamond film growth mechanism. This work demonstrated that the HF CVD method has convincing potential for the fabrication of single-crystal diamond needles in the form of regularly shaped pyramids on a large surface area, even on non-conducting substrates. The experimental results demonstrated the ability for the mass production of the single-crystal needle-like diamonds, which is important for their practical application.
WOS
Найти похожие
8.

Вид документа : Статья из журнала
Шифр издания :
Автор(ы) : Volova T. G., Golubev A. I., Nemtsev I. V., Lukyanenko A. V., Dudaev A. E., Shishatskaya E. I.
Заглавие : Laser processing of polymer films fabricated from phas differing in their monomer composition
Место публикации : Polym.: MDPI AG, 2021. - Vol. 13, Is. 10. - Ст.1553. - ISSN 20734360 (ISSN), DOI 10.3390/polym13101553
Аннотация: The study reports results of using a CO2-laser in continuous wave (3 W; 2 m/s) and quasi-pulsed (13.5 W; 1 m/s) modes to treat films prepared by solvent casting technique from four types of polyhydroxyalkanoates (PHAs), namely poly-3-hydroxybutyrate and three copolymers of 3-hydroxybutyrate: with 4-hydroxybutyrate, 3-hydroxyvalerate, and 3-hydroxyhexanoate (each second monomer constituting about 30 mol.%). The PHAs differed in their thermal and molecular weight properties and degree of crystallinity. Pristine films differed in porosity, hydrophilicity, and roughness parameters. The two modes of laser treatment altered these parameters and biocompatibility in diverse ways. Films of P(3HB) had water contact angle and surface energy of 92? and 30.8 mN/m, respectively, and average roughness of 144 nm. The water contact angle of copolymer films decreased to 80–56? and surface energy and roughness increased to 41–57 mN/m and 172–290 nm, respectively. Treatment in either mode resulted in different modifications of the films, depending on their composition and irradiation mode. Laser-treated P(3HB) films exhibited a decrease in water contact angle, which was more considerable after the treatment in the quasi-pulsed mode. Roughness parameters were changed by the treatment in both modes. Continuous wave line-by-line irradiation caused formation of sintered grooves on the film surface, which exhibited some change in water contact angle (76–80? ) and reduced roughness parameters (to 40–45 mN/m) for most films. Treatment in the quasi-pulsed raster mode resulted in the formation of pits with no pronounced sintered regions on the film surface, a more considerably decreased water contact angle (to 67–76? ), and increased roughness of most specimens. Colorimetric assay for assessing cell metabolic activity (MTT) in NIH 3T3 mouse fibroblast culture showed that the number of fibroblasts on the films treated in the continuous wave mode was somewhat lower; treatment in quasi-pulsed radiation mode caused an increase in the number of viable cells by a factor of 1.26 to 1.76, depending on PHA composition. This is an important result, offering an opportunity of targeted surface modification of PHA products aimed at preventing or facilitating cell attachment. © 2021 by the authors. Licensee MDPI, Basel, Switzerland.
Scopus
Найти похожие
9.

Вид документа : Статья из журнала
Шифр издания :
Автор(ы) : Volova, Tatiana G., Golubev, Alexey, I, Nemtsev, Ivan, V, Lukyanenko, Anna, V, Dudaev, Alexey E., Shishatskaya, Ekaterina, I
Заглавие : Laser Processing of Polymer Films Fabricated from PHAs Differing in Their Monomer Composition
Колич.характеристики :24 с
Коллективы : Russian Foundation for Basic Research/Regional State Autonomous Institution "Krasnoyarsk Regional Fund for the Support of Scientific and ScientificTechnical Activities" foundations [19-43-240012]; Ministry of Science and Higher Education of the Russian Federation [FSRZ-2020-0006]
Место публикации : Polymers: MDPI, 2021. - Vol. 13, Is. 10. - Ст.1553. - ISSN 2073-4360(eISSN), DOI 10.3390/polym13101553
Примечания : Cited References:87. - This work was supported by the Russian Foundation for Basic Research/Regional State Autonomous Institution "Krasnoyarsk Regional Fund for the Support of Scientific and ScientificTechnical Activities" foundations under Grant number 19-43-240012 (laser treatment and films properties) and by the State Assignment of the Ministry of Science and Higher Education of the Russian Federation No. FSRZ-2020-0006 (polymer synthesis).
Предметные рубрики: CHEMOMECHANICAL PROPERTIES
PHYSICOCHEMICAL PROPERTIES
SURFACE
Аннотация: The study reports results of using a CO2-laser in continuous wave (3 W; 2 m/s) and quasi-pulsed (13.5 W; 1 m/s) modes to treat films prepared by solvent casting technique from four types of polyhydroxyalkanoates (PHAs), namely poly-3-hydroxybutyrate and three copolymers of 3-hydroxybutyrate: with 4-hydroxybutyrate, 3-hydroxyvalerate, and 3-hydroxyhexanoate (each second monomer constituting about 30 mol.%). The PHAs differed in their thermal and molecular weight properties and degree of crystallinity. Pristine films differed in porosity, hydrophilicity, and roughness parameters. The two modes of laser treatment altered these parameters and biocompatibility in diverse ways. Films of P(3HB) had water contact angle and surface energy of 92 degrees and 30.8 mN/m, respectively, and average roughness of 144 nm. The water contact angle of copolymer films decreased to 80-56 degrees and surface energy and roughness increased to 41-57 mN/m and 172-290 nm, respectively. Treatment in either mode resulted in different modifications of the films, depending on their composition and irradiation mode. Laser-treated P(3HB) films exhibited a decrease in water contact angle, which was more considerable after the treatment in the quasi-pulsed mode. Roughness parameters were changed by the treatment in both modes. Continuous wave line-by-line irradiation caused formation of sintered grooves on the film surface, which exhibited some change in water contact angle (76-80 degrees) and reduced roughness parameters (to 40-45 mN/m) for most films. Treatment in the quasi-pulsed raster mode resulted in the formation of pits with no pronounced sintered regions on the film surface, a more considerably decreased water contact angle (to 67-76 degrees), and increased roughness of most specimens. Colorimetric assay for assessing cell metabolic activity (MTT) in NIH 3T3 mouse fibroblast culture showed that the number of fibroblasts on the films treated in the continuous wave mode was somewhat lower; treatment in quasi-pulsed radiation mode caused an increase in the number of viable cells by a factor of 1.26 to 1.76, depending on PHA composition. This is an important result, offering an opportunity of targeted surface modification of PHA products aimed at preventing or facilitating cell attachment.
WOS
Найти похожие
10.

Вид документа : Статья из журнала
Шифр издания :
Автор(ы) : Volova T. G., Vinogradova O. N., Zhila N. O., Peterson I. V., Kiselev E. G., Vasiliev A. D., Sukovatiy A. G., Shishatskaya E. I.
Заглавие : Properties of a novel quaterpolymer P(3HB/4HB/3HV/3HHx)
Место публикации : Polymer: Elsevier Ltd, 2016. - Vol. 101. - С. 67-74. - ISSN 00323861 (ISSN) , DOI 10.1016/j.polymer.2016.08.048
Ключевые слова (''Своб.индексиров.''): physicochemical and mechanical properties--polyhydroxyalkanoates--quaterpolymers--biocompatibility--cell culture--chain length--chains--decomposition--3-hydroxyhexanoate--degrees of crystallinity--elongation at break--physico-chemical and mechanical properties--polyhydroxyalkanoates--quaterpolymers--short chain lengths--thermal decomposition temperature--film preparation
Аннотация: Cupriavidus eutrophus В10646 was used to synthesize a series of polyhydroxyalkanoate (PHA) quaterpolymers composed of the short-chain-length 3-hydroxybutyrate (3HB), 4-hydroxybutyrate (4HB), and 3-hydroxyvalerate (3HV) and the medium-chain-length 3-hydroxyhexanoate (3HHx). The molar fraction of 3HB in the quaterpolymers varied between 63.5 and 93.1 mol.%, 3HV – between 1.1 and 24.6 mol.%, 4HB – between 2.4 and 15.6 mol.%, and 3HHx – between 0.4 and 4.8 mol.%. The properties of PHA quaterpolymers were significantly different from those of the P(3HB) homopolymer: they had much lower degrees of crystallinity (up to 30–45%), and lower melting points and thermal decomposition temperatures, with the interval between these temperatures remaining practically unchanged. Films prepared from PHA quaterpolymers were rougher and more porous than P(3HB) films; they showed higher values of elongation at break (up to 6–113%), i.e. were more elastic. Films prepared from PHA quaterpolymers were biocompatible and had no toxic effect on mouse fibroblast NIH 3T3 cells. © 2016 Elsevier Ltd
Scopus,
Смотреть статью,
WOS
Найти похожие
11.

Вид документа : Статья из журнала
Шифр издания :
Автор(ы) : Boyandin A. N., Sukhanova A. A., Nikolaeva E. D., Nemtsev I. V.
Заглавие : Chemical Modification of Films from Biosynthetic Poly-3-Hydroxybutyrate Aimed to Improvement of Their Surface Properties
Место публикации : Macromol. Sympos.: Wiley-VCH Verlag, 2021. - Vol. 395, Is. 1. - Ст.2000281. - ISSN 10221360 (ISSN), DOI 10.1002/masy.202000281
Аннотация: Films from biodegradable poly-3-hydroxybutyrate are treated with chemical reagents to improve their hydrophilicity and biocompatibility. Two approaches are tested: a single treatment with alkali, acids, oxidizing or reducing agents, and a step-by step treatment of the alkali pre-activated surface of polymer films with bromine water and amino-compounds (ammonia or triethylamine). The maximal level of hydrophilicity (the lowest water contact angle and the highest polar component of the surface free energy) is registered after a single treatment with NaOH and after the step-by-step treatment. These samples also showed the best adhesion of mouse fibroblasts of NIH 3T3 line on the film surface. So, the proposed methods can be used to enhance hydropilicity and biocompatibility of biopolymer surface. © 2021 Wiley-VCH GmbH
Scopus
Найти похожие
12.

Вид документа : Статья из журнала
Шифр издания :
Автор(ы) : Boyandin, Anatoly Nikolayevich, Sukhanova, Anna Alekseevna, Nikolaeva, Elena Dmitrievna, Nemtsev, Ivan Vasilievich
Заглавие : Chemical Modification of Films from Biosynthetic Poly-3-Hydroxybutyrate Aimed to Improvement of Their Surface Properties
Колич.характеристики :4 с
Коллективы : Ministry of Science and Higher Education of the Russian Federation [FEFE-2020-0015]
Место публикации : Macromol. Symp.: WILEY-V C H VERLAG GMBH, 2021. - Vol. 395: 4th International Conference on Progress on Polymers and Composites (NOV 26-28, 2020, ELECTR NETWORK), Is. 1. - Ст.2000281. - ISSN 1022-1360, DOI 10.1002/masy.202000281. - ISSN 1521-3900(eISSN)
Примечания : Cited References:11. - This work was carried out by the team of the scientific laboratory "Smart Materials and Structures" within the state assignment of the Ministry of Science and Higher Education of the Russian Federation for the implementation of the project "Development of multifunctional smart materials and structures based on modified polymer composite materials capable to function in extreme conditions" (No. FEFE-2020-0015). The surface of the samples was investigated using a scanning electron microscope Hitachi TM3000 in the Krasnoyarsk Regional Center of Research Equipment of Federal Research Center "Krasnoyarsk Science Center SB RAS".
Аннотация: Films from biodegradable poly-3-hydroxybutyrate are treated with chemical reagents to improve their hydrophilicity and biocompatibility. Two approaches are tested: a single treatment with alkali, acids, oxidizing or reducing agents, and a step-by step treatment of the alkali pre-activated surface of polymer films with bromine water and amino-compounds (ammonia or triethylamine). The maximal level of hydrophilicity (the lowest water contact angle and the highest polar component of the surface free energy) is registered after a single treatment with NaOH and after the step-by-step treatment. These samples also showed the best adhesion of mouse fibroblasts of NIH 3T3 line on the film surface. So, the proposed methods can be used to enhance hydropilicity and biocompatibility of biopolymer surface.
WOS
Найти похожие
13.

Вид документа : Статья из журнала
Шифр издания :
Автор(ы) : GLADYSHEV M.I., KALACHOVA G.S., SUSHCHIK N.N.
Заглавие : FREE FATTY-ACIDS OF WATER-SURFACE FILM AS INDICATORS OF PHASES OF PHYTOPLANKTON SEASONAL DYNAMICS IN THE SYDINSKY BAY OF THE KRASNOYARSK RESERVOIR
Колич.характеристики :4 с
Место публикации : DOKLADY AKADEMII NAUK SSSR: MEZHDUNARODNAYA KNIGA, 1991. - Vol. 318, Is. 4. - С. 1017-1020. - ISSN 0002-3264
Примечания : Cited References: 9
Предметные рубрики: MICROLAYER
Найти похожие
14.

Вид документа : Статья из журнала
Шифр издания :
Автор(ы) : Peng J.L., Bulcock S., Belobrov P.I., Bursill L.A.
Заглавие : Surface bonding states of nano-crystalline diamond balls
Место публикации : International Journal of Modern Physics B. - 2001. - Vol. 15, Is. 31. - С. 4071-4085. - ISSN 02179792 (ISSN) , DOI 10.1142/S0217979201007865
Ключевые слова (''Своб.индексиров.''): diamond--article--crystal structure--electron--energy transfer--nanoparticle--particulate matter--structure analysis--surface property--transmission electron microscopy
Аннотация: The rough surface of nano-crystalline diamond spheres induces surface electronic states which appear as a broadened pre-peak over approx. 15 eV at the C K-edge energy threshold for carbon in the parallel electron energy loss spectrum (PEELS). This appears to be at least partially due to 1s-?* transitions, although typically the latter occupy a range of only 4 eV for the sp2 edge of highly-oriented pyrollytic graphite (HOPG). No ?* electrons appear in the conduction band inside the diamond particles, where all electrons are sp3 hybridized. PEELS data were also obtained from a chemical vapour deposited diamond film (CVDF) and gem-quality diamond for comparison with the spectra of nano-diamonds. The density of Sp2 and Sp3 states on the surface of diamond nano-crystals is calculated for simple structural models of the diamond balls, including some conjecture about surface structures. The results are used to interpret the sp2/sp3 ratios measured from the PEELS spectra recorded as scans across the particles. Surface roughness at the atomic scale was also examined using high-resolution transmission electron microscopy (HRTEM) and electron nano-diffraction patterns were used to confirm the crystal structures.
Scopus
Найти похожие
15.

Вид документа : Статья из журнала
Шифр издания :
Автор(ы) : Maillard-Schaller E., Kuettel O.M., Diederich L., Schlapbach L., Zhirnov V.V., Belobrov P.I.
Заглавие : Surface properties of nanodiamond films deposited by electrophoresis on Si(100)
Место публикации : Diamond and Related Materials. - 1999. - Vol. 8, Is. 2-5. - С. 805-808. - ISSN 09259635 (ISSN)
Ключевые слова (''Своб.индексиров.''): energy band diagram--nanodiamond--raman spectroscopy--surface characterization--band structure--electrodeposition--electrophoresis--hydrogen--nanostructured materials--nitrogen--oxidation--oxygen--phonons--plasma applications--silicon wafers--surface properties--dielectrophoresis--negative electron affinity (nea)--phonon confinement effect--diamond films
Аннотация: The surface properties of diamond nanoparticles (40-50 A in diameter) have been investigated by X-ray photoelectron spectroscopy (XPS), UV photoelectron spectroscopy (UPS) and Raman spectroscopy. The diamond nanoparticles have been deposited on flat Si(100) substrates by electrophoresis/dielectrophoresis. The as-deposited films are strongly oxidized and present a 1-2% nitrogen content. After treatment at 850 В°C in H2 plasma for 60 min, the oxygen is removed, and the position of the C 1s core-level peak indicates a n-type electronic comportment of the diamond nanoparticles. Raman spectroscopy of the as-deposited film shows a sp3 contribution at 1321 cm-1 and a sp2 contribution around 1620 cm-1. The 12 cm-1 shift of the sp3 contribution with respect to the bulk diamond peak at 1333 cm-1 is attributed to a phonon confinement effect due to the size of the diamond particles. The H2 plasma treatment induces a size decrease of the nanocrystallites confirmed by Raman and scanning electron microscopy (SEM) measurements. UPS spectroscopy shows a negative electron affinity of -0.2 eV of the hydrogenated nanodiamond film.
Scopus
Найти похожие
16.

Вид документа : Статья из журнала
Шифр издания :
Автор(ы) : Gladyshev M.I., Kalachova G.S., Sushchik N.N.
Заглавие : Free fatty acids of surface film of water in the Sydinsky Bay of the Krasnoyarsk Reservoir
Место публикации : Internationale Revue der Gesamten Hydrobiologie. - 1993. - Vol. 78, Is. 4. - С. 575-587. - ISSN 00209309 (ISSN)
Scopus
Найти похожие
17.

Вид документа : Статья из журнала
Шифр издания :
Автор(ы) : Shishatskaya E.I., Nikolaeva E.D., Goreva A.V., Brigham C.J., Volova T.G., Sinskey A.J.
Заглавие : An in vivo study of pha matrices of different chemical composition: Tissue reaction and biodegradation
Место публикации : Cellular Transplantation and Tissue Engineering. - 2012. - Vol. 7, Is. 1. - С. 73-80. - ISSN 1815445X (ISSN)
Ключевые слова (''Своб.индексиров.''): degradable polymer matrices--degradation--phas--polyhydroxyalkanoates--subcutaneous implantation--tissue reaction
Аннотация: The study addresses consequences of subcutaneous implantation of film matrices prepared from different PHAs to laboratory animals. No negative effects of subcutaneous implantation of PHA matrices on physiological and biochemical characteristics of the animals were determined. Independently of the matrices composition and duration of the contact with the internal environment of the organism we did not observe any deviations in the behavior of animals, their growth and development, as well as blood functions. Response of the tissues to PHA matrices was comparable with the response to polylactide, but substantially less expressed at the earlier time periods after implantation. Tissues response to implantation of PHA of all types is characterized by short-term (up to 2 weeks) post-traumatic inflammation with formation of fibrous capsules by 30th-60th days with the thickness less than 100 microns, which get thinner down to 40-60 microns by 180th day as the result of involution. No differences in response of tissues and the whole organism were observed for the matrices produced from the homopolymer of 3-hydroxybutyric acid (P3HB), copolymers of 3-hydroxybutyric and 4-hydroxybutyric acids (P3HB/4HB), 3-hydroxybutyric acid and 3-hydroxyvalerianic acids (P3HB/3HV), 3-hydroxybutyric and 3-hydroxyhexanoate acids (P3HB/3HH). Macrophages and foreign-body giant cells actively participate in the response of the tissues to PHAs. In the studied conditions matrices from the copolymers containing 3-hydroxyhexanoate and 4 hydroxybutyrate were determined as more actively degraded PHA. The next less degraded matrices were matrices from the copolymer of P3HB/3HV and the most resistant were P3HB matrices. The slower degradation of PHA matrices was accompanied by delayed development of giantcells response. The studied PHA matrices can be placed in the following range by their degradation: P3HB/3HH - P3HB/4HB - P3HB/HV - P3HB.
Scopus
Найти похожие
18.

Вид документа : Статья из журнала
Шифр издания :
Автор(ы) : Boyandin A.N., Rudnev V.P., Ivonin V.N., Prudnikova S.V., Korobikhina K.I., Filipenko M.L., Volova T.G., Sinskey A.J.
Заглавие : Biodegradation of polyhydroxyalkanoate films in natural environments
Место публикации : Macromolecular Symposia. - 2012. - Vol. 320, Is. 1. - С. 38-42. - ISSN 10221360 (ISSN) , DOI 10.1002/masy.201251004
Ключевые слова (''Своб.индексиров.''): biodegradation--biopolymers--microbial degradation--polyhydroxyalkanoates--acinetobacters--acremonium--alcaligenes--burkholderia--degradation rate--degrading activities--degrading bacteria--enterobacter--hydroxyvalerate--mass loss--microbial degradation--micromycetes--natural environments--paecilomyces--poly-3-hydroxybutyrate--poly-hydroxyalkanoate--polyhydroxyalkanoates--siberia--south china sea--stenotrophomonas--trichoderma--tropical soils--viet nam--xanthomonas--bacteria--bacteriology--biopolymers--degradation--seawater--soils--tropics--biodegradation
Аннотация: Biodegradation of film specimens from polyhydroxyalkanoates (PHAs) of two types - poly-3-hydroxybutyrate (PHB) and poly-3-hydroxybutyrate-co-3- hydroxyvalerate (PHBV) - was analysed in different environments: tropical sea waters of the South China Sea (Nha Trang, Vietnam) and soils in the environs of Hanoi (Vietnam), Nha Trang (Vietnam) and Krasnoyarsk (Siberia, Russia). In seawater, the mass loss of the specimens of both types was almost equal. However, in tropical soils, PHB degraded quicker than PHBV. In the Siberian soil, the degradation rate of the PHBV was generally higher than that of PHBV. Analysis of molecular mass of PHA specimens showed its decreasing during biodegradation. In the tropical sea conditions, PHA degrading microorganisms were represented by bacteria of Enterobacter, Bacillus and Gracilibacillus genera. Among PHA degrading bacteria, Burkholderia, Alcaligenes, Bacillus, Mycobacterium and Streptomyces genera were identified in Vietnamese soils, and Variovorax, Stenotrophomonas, Acinetobacter, Pseudomonas, Bacillus and Xanthomonas genera in Siberian soils. Micromycetes of Gongronella, Paecilomyces, Penicillium and Trichoderma genera exhibited PHA degrading activity in Vietnamese soils, and Paecilomyces, Penicillium, Acremonium, Verticillium and Zygosporium genera - in Siberian soils. Copyright В© 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.
Scopus
Найти похожие
19.

Вид документа : Статья из журнала
Шифр издания :
Автор(ы) : Slabko V.V., Volova T.G., Krasnov P.O., Kuzubov A.A., Shishatskaya E.I.
Заглавие : Surface modification of bioresorbable polymer scaffolds by laser treatment
Место публикации : Biophysics. - 2010. - Vol. 55, Is. 2. - С. 234-238. - ISSN 00063509 (ISSN) , DOI 10.1134/S0006350910020120
Ключевые слова (''Своб.индексиров.''): hydrophilicity--laser irradiation--microbial biocompatible and biodegradable polymers--polyhydroxybuturate--surface properties
Аннотация: The effect of laser irradiation on the properties of the surface of films prepared from a bioresorbable polymer poly(hydroxybuturate) has been studied. To determine the spectral region of the polymer optimal for the effective action of radiation on electron molecular bonds, theoretical investigations have been performed, which have shown that, for modifying the surface of PHB scaffolds, it is expedient to use a vacuum laser at a wavelength of 160 nm. Using laser irradiation at a power from 3 to 30 W, a series of films with modified surface, from roughnesses to perforations, have been obtained. The microstructure and properties of the film surface depending on the mode of irradiation have been examined, and conditions have been found under which the contact marginal angles of film wetting with water can be decreased to 50В° (compared with 76-80В° in starting products). Thus, conditions of laser treatment of PHB scaffolds have been theoretically substantiated and experimentally realized that provide a beneficial effect on the properties of the surface without destroying the structure of the material. В© 2010 Pleiades Publishing, Ltd.
Scopus
Найти похожие
20.

Вид документа : Статья из журнала
Шифр издания :
Автор(ы) : Puzyr' A.P., Pozdnyakova I.O., Bondar' V.S.
Заглавие : Design of a luminescent biochip with nanodiamonds and bacterial luciferase
Колич.характеристики :3 с
Место публикации : Phys. Solid State: AMER INST PHYSICS, 2004. - Vol. 46, Is. 4. - С. 761-763. - ISSN 1063-7834, DOI 10.1134/1.1711469
Примечания : Cited References: 10
Аннотация: An "aluminum oxide film-adhesive layer-nanodiamond-luciferase" supramolecular structure is prepared on a flat plate. It is demonstrated that, in this structure, the enzyme retains the catalytic activity. The structure prepared can be treated as a luminescent biochip prototype for use in bioluminescent analysis. (C) 2004 MAIK "Nauka / Interperiodica".
Найти похожие
 1-20    21-25 
 

Другие библиотеки

© Международная Ассоциация пользователей и разработчиков электронных библиотек и новых информационных технологий
(Ассоциация ЭБНИТ)