Библиотека института физики им. Л.В. Киренского СО РАН

Главная

Базы данных

Труды сотрудников ИФ СО РАН - результаты поиска

Вид поиска

Каталог книг и брошюр библиотеки ИФ СО РАН

Каталог журналов библиотеки ИФ СО РАН

Труды сотрудников ИФ СО РАН

Область поиска

в найденном

Найдено в других БД:

Каталог книг и брошюр библиотеки ИФ СО РАН (1)

Формат представления найденных документов:
полный	информационный	краткий

Отсортировать найденные документы по:
автору	заглавию	году издания	типу документа

Поисковый запрос: (<.>K=conversion<.>)

Общее количество найденных документов : 53
Показаны документы с 1 по 10

1-10 11-20 21-30 31-40 41-50 51-53

Вид документа : Статья из журнала
Шифр издания :
Автор(ы) : Lim, Chang S., Aleksandrovsky A. S., Molokeev M. S., Oreshonkov A. S., Atuchin V.
Заглавие : Structural and spectroscopic effects of Li+ substitution for Na+ in LixNa1–xCaLa0.5Er0.05Yb0.45(MoO4)3 upconversion scheelite-type phosphors
Место публикации : Crystals. - 2023. - Vol. 13, Is. 2. - Ст.362. - ISSN 20734352 (eISSN), DOI 10.3390/cryst13020362
Примечания : Cited References: 63. - This study was funded by the Research Program through the Campus Research Foundation funded by Hanseo University in 2022 (2022046)
Аннотация: New triple molybdates LixNa1−xCaLa0.5(MoO4)3:Er3+0.05/Yb3+0.45 (x = 0, 0.05, 0.1, 0.2, 0.3) were manufactured successfully using the microwave-assisted sol-gel-based technique (MAS). Their room-temperature crystal structures were determined in space group I41/a by Rietveld analysis. The compounds were found to have a scheelite-type structure. In Li-substituted samples, the sites of big cations were occupied by a mixture of (Li, Na, La, Er, Yb) ions, which provided a linear cell volume decrease with the Li content increase. The increased upconversion (UC) efficiency and Raman spectroscopic properties of the phosphors were discussed in detail. The mechanism of optimization of upconversion luminescence upon Li content variation was shown to be due to the control of excitation/energy transfer channel, while the control of luminescence channels played a minor role. The UC luminescence maximized at lithium content x = 0.05. The mechanism of UC optimization was shown to be due to the control of excitation/energy transfer channel, while the control of luminescence channels played a minor role. Over the whole spectral range, the Raman spectra of LixNa1−xCaLa0.5(MoO4)3 doped with Er3+ and Yb3+ ions were totally superimposed with the luminescence signal of Er3+ ions, and increasing the Li+ content resulted in the difference of Er3+ multiple intensity. The density functional theory calculations with the account for the structural disorder in the system of Li, Na, Ca, La, Er and Yb ions revealed the bandgap variation from 3.99 to 4.137 eV due to the changing of Li content. It was found that the direct electronic transition energy was close to the indirect one for all compounds. The determined chromaticity points (ICP) of the LiNaCaLa(MoO4)3:Er3+,Yb3+ phosphors were in good relation to the equal-energy point in the standard CIE (Commission Internationale de L’Eclairage) coordinates.
Смотреть статью,
WOS,
Читать в сети ИФ
Найти похожие

Вид документа : Статья из журнала
Шифр издания :
Автор(ы) : Пятнов, Максим Владимирович, Тимофеев, Иван Владимирович
Заглавие : Фотоэлектрохимическое расщепление воды наноструктурированным электродом и зеленая водородная энергетика
Место публикации : Фотоника. - 2022. - Т. 16, Вып. 2. - С. 116-125. - ISSN 1993-7296 (ISSN), DOI 10.22184/1993-7296.FRos.2022.16.2.116.125; Photonics Rus. - ISSN 2686-844X (eISSN)
Примечания : Библиогр.: 28. - Исследование выполнено за счет гранта Российского научного фонда и Красноярского краевого фонда поддержки научной и научно-технической деятельности № 22-22-20078, https://rscf.ru/project/22-22-20078
Аннотация: В статье описан перспективный способ получения водорода – фотоэлектрохимическое расщепление воды. Этот подход сочетает непосредственное использование солнечной энергии и низкую стоимость производства фотоэлектрохимических ячеек из широко распространенных на Земле полупроводниковых материалов. Последние достижения в конструировании таких ячеек включают наноструктурирование полупроводниковых электродов плазмонными материалами.This article describes a promising hydrogen formation method, namely the photoelectrochemical water splitting. This approach combines the direct use of solar energy and low production cost of photoelectrochemical cells using the widely used semiconductor materials. The latest advances in such cell design include nanostructuring of the semiconductor electrodes with plasmonic materials.
Смотреть статью,
РИНЦ
Найти похожие

Вид документа : Статья из журнала
Шифр издания :
Автор(ы) : Sychev, Valentin V., Baryshnikov S. V., Ivanov, Ivan P., Volochaev M. N., Taran, Oxana P.
Заглавие : Hydrogenation of levulinic acid to gamma-valerolactone in the presence of Ru-containing catalysts based on carbon material "Sibunit"
Коллективы : Russian Foundation for Basic Research (RFBR)Russian Foundation for Basic Research (RFBR) [20-03-00636]
Место публикации : J. Sib. Fed. Univ. Chem. - 2021. - Vol. 14, Is. 1. - P.5-20. - ISSN 1998-2836, DOI 10.17516/1998-2836-0211; Журн. СФУ. Химия. - ISSN 2313-6049(eISSN)
Примечания : Cited References: 28. - This work was financially supported by the Russian Foundation for Basic Research (RFBR) (project No. 20-03-00636)
Предметные рубрики: BIOMASS
RUTHENIUM
DEHYDRATION
SELECTIVITY
CONVERSION
CELLULOSE
Аннотация: Nanostructured 1 and 3% catalysts containing ruthenium nanoparticles supported on the initial and oxidized at different temperatures graphite-like carbon material Sibunit-4 prepared. A features of this support are mesoporous texture, hydrothermal stability and the presence of surface oxygen-containing functional groups responsible for the distribution of Ru nanoparticles and the catalyst acidic properties. The catalysts characterized using methods TEM, XPS, N2 adsorption, pHpzc and tested in the hydrogenation of levulinic acid to γ-valerolactone. It was found that the reaction rate and GVL selectivity are influenced by solvent choice, fractional composition, and acidic properties of the support. The obtained catalysts provide high activity in the reaction of direct hydrogenation of levulinic acid to γ-valerolactone (GVL yield 98 mol.%, At 160°С, 1.2 MPa H2) and high productivity (15.9 gGVL/gCat.). Obtained catalyst can be reused several times without noticeable loss of activity.Синтезированы наноструктурированные 1 и 3 % катализаторы, содержащие наночастицы рутения, закрепленные на исходном и окисленном при разных температурах графитоподобном углеродном материале Cибунит‑4. Особенность данного носителя состоит в его мезопористой текстуре, гидротермальной устойчивости и наличии на поверхности кислородсодержащих функциональных групп, ответственных за распределение наночастиц Ru и кислотные свойства катализатора. Катализаторы исследованы физико-химическими методами (ПЭМ, РФЭС, адсорбция N2, pHтнз) и испытаны в реакции гидрирования левулиновой кислоты до γ-валеролактона. Установлено, что на скорость реакции и селективность процесса по отношению к ГВЛ оказывают влияние такие факторы, как выбранный растворитель, фракционный состав и кислотные свойства носителя. Полученные катализаторы показали высокую активность в реакции прямого гидрирования левулиновой кислоты до γ-валеролактона (выход ГВЛ 98 мол.% при 160 ºС, 1.2 МПа H2) и высокую производительность (15.9 г ГВЛ/г кат.). Данный катализатор может быть использован многократно без заметной потери активности.
Смотреть статью,
РИНЦ,
WOS,
Читать в сети ИФ
Найти похожие

Вид документа : Статья из журнала
Шифр издания :
Автор(ы) : Шабанова К. А., Логинов Ю. Ю., Буханов, Евгений Романович, Волочаев, Михаил Николаевич, Пятина С. А.
Заглавие : Влияние структуры хлоропластов на плотность фотонных состояний и эффективность преобразования солнечной энергии
Место публикации : Сиб. аэрокосм. журн. - 2021. - Т. 22, № 4. - С. 708-717. - ISSN 2712-8970, DOI 10.31772/2712-8970-2021-22-4-708-717; Sib. Aerospace J.
Примечания : Библиогр.: 22
Аннотация: Благодаря поглощению солнечной энергии в хлоропластах – зелёных пластидах – происходит преобразование солнечной энергии в энергию химических связей. Изучение процессов фотосинтеза и увеличение его эффективности актуально для разработки замкнутых систем жизнеобеспечения, в том числе, при длительных полетах в космосе. Хлоропласты в свою очередь наполнены стопками высокоупорядоченных тилакоидных мембран (гранами). На границе этих мембран и располагаются пигмент-белковые фотосинтетические комплексы. Долгое время структурным характеристикам хлоропластов не уделялось должного внимания и они изучались как изотропные вещества, однако в последние годы было показано, что они обладают анизотропными свойствами и высоким коэффициентом преобразования при разделении зарядов. В данной работе был предложен подход к более точному пространственному определению гран в хлоропластах растений и определению размеров единичного блока. Тилакоидные мембраны и границы состоящей из них граны отчетливо видны в электронном микроскопе, если пучок электронов направлен строго перпендикулярно. Было замечено, что при повороте столика разные области мембран становятся либо расплывчатыми, либо более четкими, что говорит о том, что граны в хлоропластах располагаются не в одной плоскости. Также проведено сравнение влияния разных внешних условий на структуру хлоропласта растения не только через сравнение морфологических характеристик, но и посредством численного моделирования и сравнения спектральных свойств объектов. Для численного моделирования были определены периодические решетки для основных структурных единиц хлоропластов разных образцов. На основе этих решеток были рассчитаны спектры пропускания с помощью метода трансфер матриц. Также полученные значения электромагнитной волны вдоль решетки позволили рассчитать графики плотности фотонных состояний. Результаты расчетного метода графиков плотности фотонных состояний на основе структуры хлоропластов позволили не просто оценить возможную эффективность фотосинтеза, но и напрямую связать эти модели с внешними условиями, влияющими на растение.Due to the absorption of solar energy in chloroplasts - green plastids, solar energy is converted into the energy of chemical bonds. Studying the processes of photosynthesis and increasing its efficiency is relevant for the development of closed life support systems, including during long flights in space. Chloroplasts are filled with stacks of highly ordered tilakoid membranes (granas). Pigment-protein photosynthetic complexes are located on the border of these membranes. For a long time, the structural characteristics of chloroplasts were not given due attention and they were studied as isotropic substances, but in recent years it has been shown that they have anisotropic properties and a high conversion coefficient during charge separation. In this work, an approach was proposed for a more accurate spatial determination of grains in plant chloroplasts and determination the single unit. Thylakoid membranes and the boundaries of the facet consisting of them are clearly visible in an electron microscope if the electron beam is directed strictly perpendicularly. It was noticed that when the stage is rotated, different regions of the membranes become either blurred or more distinct, which suggests that the granules in chloroplasts are not located in the same plane. Also, a comparison was made of the influence of different external conditions on the chloroplast structure of a plant, not only through a comparison of morphological characteristics, but also through numerical modeling and comparison of the objects spectral properties. For numerical simulation, periodic lattices were determined for the main structural units of chloroplasts of different samples. On the basis of these gratings, the transmission spectra were calculated using the transfer matrix method. Also, the obtained values of the electromagnetic wave along the lattice made it possible to calculate the graphs of the density of photon states. The results of the calculation method of plots of the density of photon states based on the structure of chloroplasts made it possible not only to assess the possible efficiency of photosynthesis, but also to directly relate these models to the external conditions affecting the plant.
Смотреть статью,
РИНЦ,
Читать в сети ИФ
Найти похожие

Вид документа : Статья из журнала
Шифр издания :
Автор(ы) : Zhang, Guangqing, Molokeev M. S., Ma, Qianchao, Yang, Xuening, Han, Shuiquan, Chen, Q.i., Zhong, Binnian, Ma, Bin
Заглавие : Structural analysis and optical temperature sensing performance of Eu3+-doped Ba3In(PO4)3
Место публикации : CrystEngComm. - 2020. - Vol. 22, Is. 35. - P.5809-5817. - ISSN 1466-8033, DOI 10.1039/d0ce00997k
Примечания : Cited References: 52. - This work was supported by the National Natural Science Foundation of China (Grant No. 51802172) and the Qinghai Provincial Natural Science Foundation for Young Scholars (No. 2018-ZJ-957Q)
Предметные рубрики: FLUORESCENCE INTENSITY RATIO
UP-CONVERSION EMISSIONS
RARE-EARTH IONS
Аннотация: Eu3+-Doped Ba3In(PO4)3 was synthesized through a high-temperature solid-phase method. According to the structure refinement based on X-ray diffraction and density functional theory, the crystal and energy band structures of Ba3In(1−x)(PO4)3:xEu3+ were studied and analyzed in detail. The effect of Eu3+ doping concentrations on emission was studied at an excitation wavelength of 393 nm. For the material Ba3In(1−x)(PO4)3:xEu3+(x = 0.01–0.30), the optimal doping level is confirmed to be 0.18. Due to the thermal quenching differences of Eu3+ at the 5D0 and 5D1 energy levels, and based on the temperature-variable fluorescence intensity ratio between emission peaks, the optical temperature measurement performance of this material in the temperature range from 298.15 K to 623.15 K was characterized, and the maximum absolute and relative sensor sensitivities (Sa and Sr) were determined to be 0.1002 K−1 and 4.058%, respectively. With temperature as the only variable, the color of the phosphor changes from red to yellow light with rising temperature. Besides, Sa and Sr values of this phosphor are comparable to other sensing materials. The results indicate that Eu3+-doped Ba3In(PO4)3 phosphors have great potential to be applied in optical temperature sensing.
Смотреть статью,
Scopus,
WOS
Найти похожие

Вид документа : Статья из журнала
Шифр издания :
Автор(ы) : Belyaev B. A., Afonin A. O., Ugryumov A. V., Govorun I. V., Solovev P. N., Leksikov An. A.
Заглавие : Microstrip resonator for nonlinearity investigation of thin magnetic films and magnetic frequency doubler
Место публикации : Rev. Sci. Instrum. - 2020. - Vol. 91, Is. 11. - Ст.114705. - ISSN 00346748 (ISSN), DOI 10.1063/5.0009045
Примечания : Cited References: 40. - This work was supported by the Russian Science Foundation under Grant No. 19-72-10047
Аннотация: A structure that consists of a λ/4 stepped-impedance microstrip resonator is proposed as an instrument for the investigation of nonlinear effects in thin magnetic films and also can be used as a microwave frequency doubler. A conversion efficiency of 0.65% is observed at a one-layer 100 nm Ni80Fe20 thin film at an input signal level of 4.6 W for a 1 GHz probe signal. The maximum measured conversion efficiency (1% at 1 GHz) was achieved for the 9-layer Ni80Fe20 film where 150 nm magnetic layers were separated by SiO2 layers.
Смотреть статью,
Scopus,
WOS,
Читать в сети ИФ
Найти похожие

Вид документа : Статья из журнала
Шифр издания :
Автор(ы) : Yun, Xiangyan, Zhou, Jun, Zhu, Yaohui, Molokeev M. S., Jia, Yetong, Wei, Chao, Xu, Denghui, Sun, Jiayue
Заглавие : Thermometry and up-conversion luminescence of Ln3+ (Ln = Er, Ho, Tm)-doped double molybdate LiYbMo2O8
Место публикации : J. Mater. Sci.: Mater. Electron. - 2020. - Vol. 31, Is. 21. - P.18370-18380. - ISSN 0957-4522, DOI 10.1007/s10854-020-04382-8. - ISSN 1573-482X(eISSN)
Примечания : Cited References: 41. - This work is supported by the National Natural Science Foundation of China (No. 21576002 and 61705003) and Beijing Technology and Business University Research Team Construction Project (No. PXM2019_014213_000007)
Предметные рубрики: TEMPERATURE SENSING BEHAVIOR
OPTICAL THERMOMETRY
EMISSION
PHOSPHOR
Аннотация: The discovery of stable and highly sensitive up-conversion (UC) phosphors using the fluorescence intensity ratio (FIR) is a significant challenge in the field of optical temperature sensor. Er3+/Ho3+/Tm3+-doped LiYbMo2O8 UC phosphors with excellent luminescence properties were successfully synthesized through a high-temperature solid-state reaction, and the crystal structure and UC luminescence properties were discussed in detail. The UC process has been investigated by spectra pump power dependence and further explained via the energy level diagram. All emission processes about Er3+ ions and Ho3+ ions are two-photon processes and the blue emission process about Tm3+ ions is a combination of two-photon process and three-photon process. Thermal sensing performances depended on FIR technology were estimated and the sensitivities of LiYb1−xMo2O8:xLn3+ included absolute sensitivity (Sa) and relative sensitivity (Sr) can produce particular change rules with the temperature, which can serve as excellent candidates for applications in optical temperature sensing. With the increase of temperature, the maximum values of Sr of LiYb1−xMo2O8:xLn3+ are 1.16% K−1 (0.05Er3+), 0.25% K−1 (0.01Ho3+), and 0.51% K−1 (0.01Tm3+), respectively. In addition, the Sa value of LiYb0.95Mo2O8:0.05Er3+ phosphor will reach the maximum (1.08% K−1) at 475 K, while the maximum values of Sa of LiYb0.99Mo2O8:0.01Ho3+ and LiYb0.99Mo2O8:0.01Tm3+ are 0.16% K−1, 0.14% K−1.
Смотреть статью,
Scopus,
WOS,
Читать в сети ИФ
Найти похожие

Вид документа : Статья из журнала
Шифр издания :
Автор(ы) : Nemtsev I. V., Shabanova, Olga V., Shestakov N. P., Cherepakhin A. V., Zyryanov V. Ya.
Заглавие : Morphology stability of polymethylmethacrylate nanospheres formed in water-acetone dispersion medium
Место публикации : Appl. Phys. A. - 2019. - Vol. 125, Is. 10. - Ст.738. - ISSN 0947-8396, DOI 10.1007/s00339-019-3036-4. - ISSN 1432-0630(eISSN)
Примечания : Cited References: 93
Предметные рубрики: OPAL PHOTONIC CRYSTALS
POLY(METHYL METHACRYLATE)
UP-CONVERSION
Аннотация: The aim of this study is to develop a manufacturing technique of polymethylmethacrylate (PMMA) nanospheres to produce a more stable opal template. Water-acetone mixture was used as a dispersion medium to synthesize a PMMA opal structure. Morphology features, IR vibrational spectra and glass transition temperatures of the PMMA nanospheres formed in the water-acetone dispersion medium (nanospheres A) have been studied comparing with the same prepared in distilled water solution without acetone (nanospheres B). A dependence of a shrinkage degree of the nanoparticles on the acetone volume has been investigated. It has been revealed that under an electron beam action the shrinkage degree of the nanospheres A is in the range of 7-16% while the shrinkage of the nanospheres B is 18-25% at the same conditions. The nanospheres A are less flexible and soft as compared to the nanospheres B. Additionally, an ability of the PMMA nanoparticles fabricated in the water-acetone dispersion medium to form the ordered opal structures is demonstrated to be the similar to the nanospheres B.
Смотреть статью,
Scopus,
WOS,
Читать в сети ИФ
Найти похожие

Вид документа : Статья из журнала
Шифр издания :
Автор(ы) : Vyunishev A. M., Chirkin A. S.
Заглавие : Frequency doubling in periodic nonlinear photonic crystals mediated by random layers
Место публикации : Opt. Lett.: Optical Society of America, 2017. - Vol. 42, Is. 6. - P.1189-1192. - ISSN 01469592 (ISSN), DOI 10.1364/OL.42.001189
Примечания : Cited References: 26. - Council of the President of the Russian Federation (MK-2908.2015.2); Russian Foundation for Basic Research (RFBR) (15-02-03838). The authors thank I. S. Baturin for fruitful discussions and D. P. Agapov for help.
Ключевые слова (''Своб.индексиров.''): conversion efficiency--crystal structure--efficiency--photonic crystals--ferroelectric crystal--frequency-doubling--intensity oscillations--intermediate layers--nonlinear photonic crystals--periodically poled structures--second harmonics--statistical frequency--frequency doublers
Аннотация: We study the frequency doubling in a quadratic nonlinear photonic crystal consisting of periodically poled structures mediated by uniform layers with random lengths. These structures can be formed by new local impact methods for ferroelectric crystal structuring. The statistical frequency doubling theory is developed for such structures. The effect of the number of random layers and variation in their thicknesses on the second-harmonic conversion efficiency is clarified. It is demonstrated that a proper choice of the intermediate layer thickness can enhance or suppress the conversion efficiency. A new type of the Makerfringes-like second-harmonic intensity oscillations is predicted. © 2017 Optical Society of America.
Смотреть статью,
Scopus,
WOS,
Читать в сети ИФ
Найти похожие

10.

Вид документа : Статья из журнала
Шифр издания :
Автор(ы) : Lim C. S., Atuchin V. V., Aleksandrovsky A. S., Molokeev M. S., Oreshonkov A. S.
Заглавие : Incommensurately modulated structure and spectroscopic properties of CaGd2(MoO4)4:Ho3+/Yb3+ phosphors for up-conversion applications
Место публикации : J. Alloys Compd.: Elsevier, 2017. - Vol. 695. - P.737-746. - ISSN 09258388 (ISSN), DOI 10.1016/j.jallcom.2016.06.134
Примечания : Cited References: 60. - This research was supported by the Basic Science Research Program through the National Research Foundation of Korea funded by the Ministry of Education (2015-058813) and the Russian Foundation for Basic Research (15-52-53080). VVA, ASA and ASO were partially supported by the Ministry of Education and Science of the Russian Federation.
Ключевые слова (''Своб.индексиров.''): modulation--molybdate--raman--sol-gel synthesis--upconversion--xrd
Аннотация: CaGd2(MoO4)4:Ho3+/Yb3+ phosphors doped by Ho3+ and Yb3+ (Ho3+ = 0 and 0.05, and Yb3+ = 0, 0.35, 0.40, 0.45 and 0.50) were successfully synthesized by the microwave sol-gel method. The synthesized particles, being formed after heat-treatment at 900 °C for 16 h, showed a well crystallized morphology. All compounds are (3 + 2)D incommensurately modulated with superspace group I41/a(α,β,0)00(-β,α,0)00. It was found that parameter (α2 + β2)1/2 is proportional to cell parameter a for all studied compositions and, therefore, modulation vector k is the same for all known CaRE2(MoO4)4 compounds. The modulation vector invariance is a specific and valuable feature of this type of the structure. Under the excitation at 980 nm, the doped particles exhibited the yellow emission composed of green (545-nm) and red (655-nm) emission bands due to frequency upconversion (UC). The pump power dependence and CIE chromaticity of the UC emission were evaluated. The shape of UC bands in CaGd2(MoO4)4:Ho3+/Yb3+ is dependent on the Yb content due to the influence of the crystal field affecting a holmium ion. 13 Raman-active modes of the CaGd2(MoO4)4 lattice were identified via a comparison of experimental Raman spectra and the lattice dynamics simulation results. Four additional Raman lines were found in the region of stretching vibrations and, at least, two additional modes are present in the bending mode region. These additional modes are ascribed to incommensurate crystal lattice modulation. Luminescence bands of Ho ions are severely broadened due to a statistical disorder in the CaGd2−xYby (MoO4)4 lattice.
Смотреть статью,
Scopus,
WOS,
Читать в сети ИФ
Найти похожие