116 results on '"A. D. Bulanov"'
Search Results
2. Doppler-guided transanal hemorrhoidal dearterilization versus conventional hemorrhoidectomy for treatment of hemorrhoids – early and long-term postoperative results
- Author
-
V. Popov, A. Yonkov, E. Arabadzhieva, E. Zhivkov, S. Bonev, D. Bulanov, V. Tasev, G. Korukov, L. Simonova, N. Kandilarov, A. Taseva, and V. Dimitrova
- Subjects
Hemorrhoids ,Conventional hemorrhoidectomy ,Transanal hemorrhoidal dearterilization ,Postoperative pain ,Long-term outcomes ,Surgery ,RD1-811 - Abstract
Abstract Background A variety of effective methods for treatment of hemorrhoids has been proposed. In recent years, there has been an increasing number of studies comparing transanal hemorrhoidal dearterilization (THD) and conventional hemorrhoidectomy (CH), but the focus of most studies has been about the early postoperative results. The data about long-term outcomes is still limited. We aimed to compare Doppler-guided THD and CH with regard to early and long-term postoperative results. Methods The conducted prospective research included 287 patients who underwent CH (167 cases) or Doppler-guided THD with mycopexy (120 patients) between November 2010 and December 2015. Information on hemorrhoidal stage, demographic data, presenting symptoms, complications, duration of hospital stay, postoperative pain, patients’ satisfaction and follow-up were obtained. Statistical tests were performed by SPSS 19.0. Results There was no significant difference between the studied groups according to gender, mean age, preoperative prolapse, pain and pruritus, hemorrhoidal stage and postoperative complications. Preoperative bleeding was more frequent in THD group (p = 0,002). The mean visual analog scale (VAS) pain scores in CH and THD groups on days 1, 2 and 7 were 7.01 vs 5.03, 5.07 vs 2.98, 2.39 vs 0,57 (p = 0,000). Practically, there was no difference in VAS on day 30 and patients’ satisfaction at the 18th month. Mean hospital stay was 5,13 (CH) and 3,38 days (THD), p = 0,000. The postoperative follow-up was between 18 and 78 months (mean 46 ± 16 months). During this stage, 5 patients (2,99%) in CH group required surgery for recurrence. In THD group, 3 patients (2,5%), all with 4th-degree hemorrhoids underwent additional procedures (p 0,802). Conclusions Doppler-guided THD seems to be an efficient and safe option for treatment of hemorrhoids, related to lower postoperative pain and excellent, similar long-term outcomes compared to CH. For advanced grades of hemorrhoids, Doppler-guided THD could be a valuable alternative, but there is a need for patients’ selection. Trial registration (retrospectively registered) researchregistry3090.
- Published
- 2019
- Full Text
- View/download PDF
3. Indocyanine Green Fluorescence for Liver Assessment and Imaging-Guided Resection of Colorectal Metastases: A Case Report
- Author
-
E. Arabadzhieva, S. Bonev, D. Bulanov, L. Simonova, E. Zhivkov, G. Korukov, Zh. Shavalov, M. Velizarova, D. Svinarov, and A. Yonkov
- Abstract
Introduction Liver resection is widely accepted as a treatment option for primary liver cancer and metastases. The goal of surgery is to resect all tumours with negative histological margins while preserving sufficient functional hepatic parenchyma and reducing postoperative complications. The use of Indocyanine green (ICG) for liver function assessment and fluorescence image-guided surgery could be used to achieve that goal. Clinical Case Description We present the case of a 62-year-old female patient with diagnosed sigmoid colon cancer with four bilobar liver metastases who underwent a simultaneous sigmoid resection and ICG fluorescence image-guided liver resection 3 days after preoperative ICG liver function assessment. We decided to perform liver-sparing resection having in mind the liver metastases’ number, size and location and the slightly impaired liver function (ICG retention rate 15 – ICGR15 was 14,02%). All liver tumours were removed without complications, and the resected margins were all microscopically free of tumour tissue (R0 resection). The postoperative period was uneventful, without any signs of postoperative liver failure. Conclusions ICGR15 can be considered a safe and informative marker for liver function and indirectly for the degree of portal hypertension. ICG fluorescence provides an additional method to assist intra-operative tumour identification. The best timing of injection requires further study.
- Published
- 2023
4. Study of the Impurity Composition of Isotopically Enriched Germane 70GeH4 by Gas Chromatography–Mass Spectrometry
- Author
-
A. Yu. Sozin, V. A. Krylov, O. Yu. Chernova, T. G. Sorochkina, A. D. Bulanov, O. Yu. Troshin, S. A. Adamchik, and A. Yu. Lashkov
- Subjects
General Engineering ,General Materials Science - Published
- 2022
5. Preparation of High-Purity Silicon-28 Tetrachloride from Silicon-28 Tetrafluoride
- Author
-
O. Yu. Troshin, A. D. Bulanov, Yu. P. Kirillov, A. M. Potapov, P. A. Otopkova, M. E. Komshina, K. F. Ignatova, and A. A. Ermakov
- Subjects
Inorganic Chemistry ,General Chemical Engineering ,Materials Chemistry ,Metals and Alloys - Published
- 2022
6. Effect of the Isotopic Composition of Fe on the Kinetics of Its α → γ Phase Transition
- Author
-
Yu. S. Belozerov, A. D. Plekhovich, O. Yu. Troshin, A. D. Bulanov, A. M. Kut’in, and Yu. P. Kirillov
- Subjects
Inorganic Chemistry ,General Chemical Engineering ,Materials Chemistry ,Metals and Alloys - Published
- 2022
7. Preparation of Single-Crystal Isotopically Enriched 70Ge by a Hydride Method
- Author
-
V. A. Gavva, O. Yu. Troshin, S. A. Adamchik, A. Yu. Lashkov, N. V. Abrosimov, A. M. Gibin, P. A. Otopkova, A. Yu. Sozin, and A. D. Bulanov
- Subjects
Inorganic Chemistry ,General Chemical Engineering ,Materials Chemistry ,Metals and Alloys - Published
- 2022
8. Effect of the Isotopic Composition of Fe on Its Linear Thermal Expansion Coefficient
- Author
-
M. O. Steshin, A. D. Bulanov, A. S. Shipilova, O. Yu. Troshin, Yu. S. Belozerov, A. V. Knyazev, and B. N. Kodess
- Subjects
Inorganic Chemistry ,Materials science ,General Chemical Engineering ,Materials Chemistry ,Metals and Alloys ,Thermodynamics ,Isotopic composition ,Thermal expansion - Published
- 2021
9. Thermal Structure of the Filtration Combustion Wave of CаH2 in a Flow of a SiF4 + H2 Mixture
- Author
-
A. Yu. Lashkov, O. Yu. Troshin, and A. D. Bulanov
- Subjects
Calcium hydride ,Hydrogen ,General Chemical Engineering ,chemistry.chemical_element ,General Chemistry ,Mechanics ,Wake ,Combustion ,law.invention ,chemistry.chemical_compound ,chemistry ,law ,Thermal ,Silicon tetrafluoride ,Head (vessel) ,Filtration - Abstract
The head and wake waves of filtration combustion of calcium hydride in a flow of a mixture of silicon tetrafluoride and hydrogen at silicon tetrafluoride weight fractions of 0.8, 0.85, 0.9, and 0.98 were studied. The spatial profiles of the combustion waves were constructed. With their aid, the thermal structure of the head and wake waves was found, and the width of each zone in the combustion wave for different compositions of the gas phase was determined. With increasing concentration of the reagent gas in the flow, the reaction zone width increases in the head wave and decreases in the wake wave. The structure of the head wave corresponds to the intermediate combustion wave, and the structure of the wake wave, to the normal combustion wave.
- Published
- 2021
10. An Effect of the Reagent Concentration in the Flow of a Gas Mixture on the Parameters of the Combustion Wave of CaH2 in SiF4
- Author
-
O. Yu. Troshin, A. D. Bulanov, and A. Yu. Lashkov
- Subjects
Exothermic reaction ,Chemistry ,Wave propagation ,General Chemical Engineering ,Thermodynamics ,02 engineering and technology ,General Chemistry ,010402 general chemistry ,021001 nanoscience & nanotechnology ,Combustion ,01 natural sciences ,0104 chemical sciences ,chemistry.chemical_compound ,Reagent ,Silicon tetrafluoride ,Mass concentration (chemistry) ,Physics::Chemical Physics ,0210 nano-technology ,Porous medium ,Mass fraction - Abstract
The dependence has been investigated of the maximum temperature in the reaction front, the linear velocity of the combustion wave of CaH2 in a mixture of gases SiF4 and H2 with the formation of SiH4, and the conversion of calcium hydride on the initial mass concentration of silicon tetrafluoride. The experimental data have been obtained in a vertical flow reactor with forced gas filtration in the range of SiF4 mass fractions of 0.7–0.98. The results of the experiment have been compared with the data of calculation according to the classical physical and mathematical model of the exothermic reaction wave propagation in a porous medium during gas blowing. The similarities and differences have been established between the experimental and calculated values of the maximum temperature in the reaction front, the linear velocity of the combustion wave propagation, and the conversion of the solid-phase reagent.
- Published
- 2021
11. Isotope analysis of highly enriched 'silicon-28' by high-resolution inductively coupled plasma mass spectrometry using an internal standard
- Author
-
A. Yu. Lashkov, A. D. Bulanov, A. I. Suchkov, A. M. Potapov, P. A. Otopkova, Program of Fundamental Scientific Research of Governmental Academies of Sciences for 2019-2021, topic No. 0095-2019-0001., and Программа фундаментальных научных исследований государственных академий наук на 2019-2021 годы № темы 0095-2019-0001
- Subjects
Matrix (chemical analysis) ,Isotope ,Silicon ,chemistry ,Stable isotope ratio ,Analytical chemistry ,chemistry.chemical_element ,Isotopes of silicon ,Inductively coupled plasma ,Mass spectrometry ,Inductively coupled plasma mass spectrometry ,Analytical Chemistry - Abstract
In order to study the isotopic effects in semiconductor materials, single crystals of high chemical and isotopic purity are required. The reliability of the obtained data on the magnitude and the direction of isotopic shifts depends on the accuracy of determining the concentration of all stable isotopes. In the isotopic analysis of enriched “silicon-28” with a high degree of enrichment ( 99.99%), it is necessary to determine the impurities of 29Si and 30Si isotopes at the level of 10-3 ¸ 10-5 at. %. At this concentration level, these isotopes can be considered as impurities. It is difficult to achieve high measurement accuracy with simultaneous registration of the main and “impurity” isotopes in such a wide range of concentrations. The registration of analytical signals of silicon isotopes must be carried out in the solutions with different matrix concentrations. The use of the solutions with the high concentration of the matrix element requires the introduction of corrections for matrix noise and the drift of the instrument sensitivity during the measurement. It is possible to reduce the influence of the irreversible non-spectral interference and sensitivity drift by using the method of internal standardization. The inconsistency of the literature data on the selection criteria for the internal standard required studying the behavior of the signals of the “candidates for the internal standard” for the ELEMENT 2 single-collector high-resolution inductively coupled plasma mass spectrometer on the matrix element concentration and the nature of the solvent, as well as on the solution nebulizing time. Accounting for the irreversible non-spectral matrix noise and instrumental drift in isotopic analysis of enriched “silicon-28” and initial 28SiF4 by inductively coupled plasma mass spectrometry had allowed us to reduce by 3-5 times the random component and by more than an order of magnitude the systematic component of the measurement error in comparison with the external standard method. This made it possible to carry out, with sufficient accuracy, the operational control of the isotopic composition of enriched “silicon-28”, both in the form of silicon tetrafluoride and polycrystalline silicon obtained from it, using a single serial device in the range of isotopic concentrations 0.0001–99.999%.Key words: high-resolution inductively coupled plasma mass spectrometry, isotope analysis, isotopically enriched silicon, internal standard DOI: http://dx.doi.org/10.15826/analitika.2021.25.2.009P.A. Otopkova, A.M. Potapov, A.I. Suchkov, A.D. Bulanov, A.Yu. Lashkov G.G. Devyatykh Institute of Chemistry of High-Purity Substances of the Russian Academy of Sciences (IChHPS RAS), 49 Tropinina St., Nizhny Novgorod, 603951, Russian Federation, Для изучения изотопических эффектов в полупроводниковых материалах требуются монокристаллы с высокой химической и изотопной чистотой. Надежность полученных данных о величине и направлении изотопических сдвигов зависит от точности определения концентрации всех стабильных изотопов. При изотопном анализе обогащенного “кремния-28” с высокой степенью обогащения (более 99.99 %) необходимо определять примеси изотопов 29Si и 30Si на уровне 10-3 ¸ 10-5 ат. %. На таком уровне концентраций указанные изотопы можно рассматривать как примеси. Достижение высокой точности измерений при одновременной регистрации основного и “примесных” изотопов в таком широком интервале концентраций затруднительно. Регистрацию аналитических сигналов изотопов кремния приходится проводить на растворах с разной концентрацией матрицы. Использование растворов с высокой концентрацией матричного элемента требует введения поправок на матричные помехи и дрейф чувствительности прибора в процессе измерения. Снизить влияние необратимых неспектральных помех и дрейфа чувствительности можно при использовании метода внутренней стандартизации. Противоречивость литературных данных о критериях выбора внутреннего стандарта потребовала исследования поведения сигналов элементов “кандидатов во внутренний стандарт“ для одноколлекторного масс-спектрометра высокого разрешения с индуктивно связанной плазмой ELEMENT 2 от концентрации матричного элемента и природы растворителя, а также от времени распыления раствора. Учет необратимых неспектральных матричных помех и аппаратного дрейфа при изотопном анализе обогащенного “кремния-28” и исходного 28SiF4 методом масс-спектрометрии с индуктивно связанной плазмой позволил снизить в 3-5 раз случайную составляющую и более чем на порядок систематическую составляющую погрешности измерения по сравнению с методом внешнего стандарта. Это позволило проводить с достаточной точностью оперативный контроль изотопного состава обогащенного “кремния-28”, как в виде тетрафторида кремния, так и получаемого из него поликристаллического кремния с помощью одного серийного прибора в интервале изотопных концентраций 0.0001–99.999 ат. %.Ключевые слова: масс-спектрометрия высокого разрешения с индуктивно связанной плазмой, изотопный анализ, изотопнообогащенный кремний, внутренний стандартDOI: http://dx.doi.org/10.15826/analitika.2021.25.2.009
- Published
- 2021
12. Analysis of High-Purity Silane of Natural and Isotopically Enriched Composition by Gas Chromatography–Mass-Spectrometry
- Author
-
T. G. Sorochkina, O. Yu. Chernova, V. A. Krylov, A. Yu. Sozin, O. Yu. Troshin, A. D. Bulanov, N. D. Grishnova, A. P. Kotkov, and A. I. Skosyrev
- Subjects
chemistry.chemical_classification ,010401 analytical chemistry ,Inorganic chemistry ,010402 general chemistry ,Magnesium silicide ,01 natural sciences ,Silane ,0104 chemical sciences ,Analytical Chemistry ,law.invention ,chemistry.chemical_compound ,chemistry ,Impurity ,law ,Carbon dioxide ,Silicon tetrafluoride ,Gas chromatography–mass spectrometry ,Distillation ,Alkyl - Abstract
The impurity composition of natural and isotopically enriched silane obtained from magnesium silicide and silicon tetrafluoride is studied by gas chromatography–mass-spectrometry. The impurities characteristic of silane with natural and isotopically enriched composition are atmospheric gases; carbon dioxide; hydrides; saturated, unsaturated, and aromatic hydrocarbons; halogenated hydrocarbons; alkyl derivatives and silane homologues, siloxanes. The impurity content of high-purity silane does not exceed 10–7–10–5 mol % After synthesis, the concentrations of impurities in the silane and fractions isolated by its distillation purification lie in the range n × 10–6 − n × 10 mol % The limits of detection for impurities are 1 × 10–8–9 × 10–4 mol %
- Published
- 2020
13. Preparation of Isotopically Enriched Polycrystalline Germanium via Monogermane Pyrolysis
- Author
-
V. A. Lipskiy, V. A. Gavva, and A. D. Bulanov
- Subjects
010302 applied physics ,Materials science ,Hydride ,General Chemical Engineering ,Thermal decomposition ,Metals and Alloys ,Analytical chemistry ,chemistry.chemical_element ,Germanium ,02 engineering and technology ,021001 nanoscience & nanotechnology ,01 natural sciences ,Decomposition ,Inorganic Chemistry ,chemistry ,Impurity ,Yield (chemistry) ,0103 physical sciences ,Materials Chemistry ,Crystallite ,0210 nano-technology ,Pyrolysis - Abstract
High-purity isotopically enriched germanium has been prepared by a hydride method, and the main factors capable of reducing the germanium yield in the monogermane pyrolysis process have been identified. To raise the germanium yield, we have optimized pyrolysis conditions in a laboratory-scale flow apparatus. At a monogermane flow rate at the reactor inlet of 30 mL/min, the optimal monogermane decomposition temperature is 420–450°C. Such conditions ensure a decomposition rate of ~6 g/h and a high product yield and make it possible to obtain most of the germanium in polycrystalline form. Using isotopically enriched monogermane pyrolysis, we have obtained high-purity isotopically enriched germanium samples in the form of polycrystalline ingots with a yield above 95%. The ingots are n-type and range in resistivity from 25 to 50 Ω cm. The content of regulated impurities in the 72Ge-,73Ge-, 74Ge-, and 76Ge-enriched germanium ingots thus prepared does not exceed 0.01 to 1 ppm by weight.
- Published
- 2020
14. Isotopic Analysis of Highly Enriched Crystalline 28Si and Initial 28SiF4 by High-Resolution Inductively Coupled Plasma Mass Spectrometry
- Author
-
A. E. Kurganova, A. I. Suchkov, A. D. Bulanov, A. Yu. Lashkov, P. A. Otopkova, and A. M. Potapov
- Subjects
Isotope ,Chemistry ,Orders of magnitude (temperature) ,010401 analytical chemistry ,Analytical chemistry ,Isotope dilution ,010402 general chemistry ,Mass spectrometry ,01 natural sciences ,0104 chemical sciences ,Analytical Chemistry ,Impurity ,Inductively coupled plasma ,Inductively coupled plasma mass spectrometry ,Isotope analysis - Abstract
A procedure is described for determining the isotopic composition of highly enriched silicon as elementary 28Si and initial 28SiF4 by a single collector double focusing sector field ICP MS over a wide range of isotope concentrations (more than 6 orders of magnitude). To expand the range of measured isotopic concentrations, the signals of the main and “impurity” isotopes were recorded in solutions of different concentrations. The determination of the matrix effects and mass discrimination factors was carried out using the isotopic dilution method. This procedure allowed us to reach the uncertainty of measuring the concentration of the main isotope of ten thousandths of a percent in enriching >99.999% on a high-resolution single-collector inductively coupled plasma mass spectrometer.
- Published
- 2019
15. Modeling Iron Pentacarbonyl Ultrapurification in a Vertical Distillation Apparatus
- Author
-
Yu. S. Belozerov, A. D. Bulanov, A. M. Potapov, M. O. Steshin, V. A. Shaposhnikov, and Yu. P. Kirillov
- Subjects
Materials science ,General Chemical Engineering ,Diffusion ,Thermodynamics ,chemistry.chemical_element ,Fraction (chemistry) ,02 engineering and technology ,01 natural sciences ,law.invention ,Inorganic Chemistry ,chemistry.chemical_compound ,Impurity ,law ,0103 physical sciences ,Vaporization ,Materials Chemistry ,Physics::Atomic Physics ,Distillation ,Physics::Atmospheric and Oceanic Physics ,Condensed Matter::Quantum Gases ,010302 applied physics ,Condensed Matter::Other ,Condensation ,Metals and Alloys ,021001 nanoscience & nanotechnology ,Iron pentacarbonyl ,chemistry ,0210 nano-technology ,Cobalt - Abstract
This paper presents a mathematical model for the ultrapurification of substances via distillation in a closed vaporization–condensation system, where vapor condenses on a flowing down liquid film. We jointly analyze the mechanisms behind vaporization, vapor transport, condensation, condensate motion, and impurity diffusion in vaporizing liquid. Examining the removal of cobalt impurities from iron pentacarbonyl as an example, we assess the degree of purification as a function of vaporization and condensation temperatures, vaporization area, the fraction of liquid vaporized, and the radius and height of the condensation tube. Using experimentally determined temperature-dependent effective separation coefficients and the mathematical model, we find diffusion coefficients and equilibrium separation coefficients of cobalt, tungsten, and chromium impurities in iron pentacarbonyl.
- Published
- 2019
16. Study of the Stability of a Number of Molecular Impurities in Monosilane
- Author
-
A. Yu. Sozin, A. P. Kotkov, A. D. Bulanov, N. D. Grishnova, A. I. Skosyrev, O. Yu. Chernova, M. N. Matveeva, T. G. Sorochkina, O. Yu. Troshin, and V. A. Krylov
- Subjects
chemistry.chemical_classification ,Ethylene ,General Chemical Engineering ,Inorganic chemistry ,chemistry.chemical_element ,02 engineering and technology ,General Chemistry ,010402 general chemistry ,021001 nanoscience & nanotechnology ,01 natural sciences ,Silane ,0104 chemical sciences ,chemistry.chemical_compound ,chemistry ,Acetylene ,Impurity ,Fluorine ,Tetrafluoroethylene ,Disilane ,0210 nano-technology ,Alkyl - Abstract
Chromatography-mass-spectrometry was used to examine the stability of admixtures of C1−C7 hydrocarbons, fluorine and chlorinated derivatives of hydrocarbons, alkyl derivatives of silane, homologs of monosilane, and siloxanes in monosilane in its storage in molybdenum-glass ampules and stainless-steel cylinders. It was found that, in the case of storage in glass ampules, the concentration of ethylene and tetrafluoroethylene admixtures decreases and that of ethyl silane and disilane increases. When monosilane is stored in a stainless steel cylinder, the concentration of the acetylene admixture it contains changes.
- Published
- 2019
17. Gas chromatographic determination of silicon fluoride-chlorides SiСlnF4-n (n = 0 ÷ 4) obtained by the reaction of silicon tetrafluoride with aluminum chloride (III)
- Author
-
А. А. Ermakov, О. Yu. Troshin, А. Yu. Sozin, А. D. Bulanov, О. Yu. Chernova, and Т. G. Sorochkina
- Subjects
Materials science ,Chromatography ,Silicon ,Thermal conductivity detector ,chemistry.chemical_element ,Chloride ,Analytical Chemistry ,chemistry.chemical_compound ,chemistry ,Molybdenum ,Aluminium ,medicine ,Silicon tetrachloride ,Silicon tetrafluoride ,Gas chromatography ,medicine.drug - Abstract
It is for the first time that the method of gas chromatography was used for the determination of silicon fluoride-chlorides SiСl n F 4-n ( n = 0 ÷ 4) which are the initial, intermediate and final substances while producing silicon tetrachloride from silicon tetrachloride and aluminum chloride (III). The analysis of samples taken during this reaction was carried out using the "Tsvet - 800" gas chromatographer. The samples were injected into the instrument using a vacuum dosing system. To separate the components, a chromatographic column made of molybdenum glass with a length of 5 m and an internal diameter of 3 mm was used. It was filled with a Chromatone N-AW-HMDS (grain size 0.250-0.315 mm) with 15% methylsilicon elastoplastic E-301. The registration of silicon fluoride-chlorides was implemented using a thermal conductivity detector. The identification of SiF 4 and SiCl 4 in the mixture was conducted by comparing the times of holding the chromatographic peaks with the times of holding these individual substances. The times of holding not available for SiClF 3 , SiCl 2 F 2 , SiCl 3 F in the individual states were determined using the dependence of the logarithm of the corrected holding time on their molecular mass. The concentrations of silicon fluoride-chlorides were determined using the internal normalization method. The data were obtained on the changes in the concentrations of these substances during the synthesis of silicon tetrachloride. The confirmation of the correctness of the analysis results was made using the method of varying the size of the sample. Key words: silicon fluoride-chlorides, gas chromatography, identification, calibration factor, correctness (Russian) DOI: http://dx.doi.org/10.15826/analitika.2019.23.4.011 Т .G. Sorochkina, О .Yu. Chernova, О .Yu. Troshin, А .Yu. Sozin, А .D. Bulanov, А . А . Ermakov G.G. Devyatykh Institute of Chemistry of High-Purity Substances of the Russian Academy of Sciences, ul. Tropinina 49, Nizhny Novgorod, 603950, Russian Federation
- Published
- 2019
18. Elemental analysis of iron pentacarbonyl by inductively coupled plasma mass spectrometry
- Author
-
A. M. Potapov, Yu. S. Belozerov, A. I. Suchkov, M. O. Steshin, and A. D. Bulanov
- Subjects
chemistry.chemical_compound ,chemistry ,Elemental analysis ,Analytical chemistry ,Inductively coupled plasma mass spectrometry ,Analytical Chemistry ,Iron pentacarbonyl - Published
- 2019
19. High–resolution FTIR spectroscopic study of 73GeH4 up to 2300 cm−1
- Author
-
Olga Vasilievna Gromova, Elena Sergeevna Bekhtereva, M.A. Koshelev, N.I. Raspopova, O.N. Ulenikov, Peter Sennikov, I.A. Velmuzhova, and A. D. Bulanov
- Subjects
Radiation ,Materials science ,010504 meteorology & atmospheric sciences ,Hamiltonian model ,Resolution (electron density) ,Fourier transform spectrometers ,Analytical chemistry ,High resolution ,01 natural sciences ,Atomic and Molecular Physics, and Optics ,Spectral line ,chemistry.chemical_compound ,chemistry ,Germane ,0103 physical sciences ,Fourier transform infrared spectroscopy ,010303 astronomy & astrophysics ,Spectroscopy ,0105 earth and related environmental sciences ,Line (formation) - Abstract
The spectra of germane enriched up to 99.9 % of 73GeH4 were recorded with a high resolution (0.003 cm − 1 ) at different pressures with the Bruker IFS 125HR Fourier transform spectrometer (Nizhny Novgorod, Russia) in the region of 650–4400 cm − 1 and analyzed in the Dyad and Pentad region. The 9208 transitions belonging to the seven “cold” bands (6987 transitions) of the Dyad and Pentad and to the nine “hot” Dyad–Pentad bands (2221 transitions) were assigned and theoretically analysed in the frame of the effective Hamiltonian model. The obtained set of 68 fitted parameters reproduces the initial 9208 experimental line positions with the d r m s = 2.82 × 10 − 4 cm − 1 .
- Published
- 2018
20. Study of magnetic properties of isotopically enriched 56Fe at different magnetic field strength values
- Author
-
Sergey Melnikov, Alexander G. Savchenko, Pavel Mogilnikov, M. F. Churbanov, Yuriy Belozerov, Oleg Troshin, A. M. Potapov, G. A. Politova, A. D. Bulanov, and Igor Belyaev
- Subjects
Materials science ,Condensed matter physics ,Magnetic field - Published
- 2021
21. The comparability of the determination of the molar mass of silicon highly enriched in 28 Si: results of the CCQM-P160 interlaboratory comparison and additional external measurements
- Author
-
Heidi Goenaga-Infante, Alexander M. Potapov, Tongxiang Ren, Alexander G. Sharin, Dmitri G. Aref'Ev, Polina A. Otopkova, Rüdiger Kessel, Sarah Hill, Vladimir Marchin, Zoltán Mester, Olaf Rienitz, Philip J. H. Dunn, Jun Wang, Lu Yang, Axel Pramann, Tomohiro Narukawa, Kyoung-Seok Lee, Yong-Hyeon Yim, Robert D. Vocke, Savelas A. Rabb, Juris Meija, Dmitriy Malinovskiy, Jochen Vogl, and Andrei D. Bulanov
- Subjects
Materials science ,Silicon ,IAWG ,Analytical chemistry ,chemistry.chemical_element ,Context (language use) ,engineering.material ,CCQM-P160 ,01 natural sciences ,010309 optics ,symbols.namesake ,0103 physical sciences ,Avogadro constant ,International System of Units ,010306 general physics ,revision of the SI ,Molar mass ,Kilogram ,molar mass ,General Engineering ,silicon ,Metrology ,Polycrystalline silicon ,chemistry ,IRWG ,symbols ,engineering - Abstract
An international comparison study on the accurate determination of the molar mass M(Si) of silicon artificially enriched in 28Si (x(28Si) > 0.9999 mol mol−1) has been completed. The measurements were part of the high level CCQM-P160 pilot study assessing the ability of National Metrology Institutes (NMIs) and Designated Institutes (DIs) to make such measurements at the lowest possible levels of measurement uncertainty and to identify possible difficulties when measuring this kind of sample. This study supports the molar mass measurements critical to disseminating the silicon route to realizing the new definitions for the kilogram and the mole. Measurements were also made by one external research institute and an external company. The different institutes were free to choose their experimental (mass spectrometric) set-ups and equipment, thereby enabling also the comparison of different techniques. The investigated material was a chemically pure, polycrystalline silicon material. The subsequent modified single crystalline secondary product of this material was intended for the production of silicon which was used for two additional spheres in the context of the redetermination of the Avogadro constant NA, required for the revision of the International System of Units (SI) via fundamental constants which came into force from May 2019. The CCQM pilot study was organized by Physikalisch-Technische Bundesanstalt (PTB). Aqueous silicon solutions were shipped to all participating institutions. The data analysis as well as the uncertainty modelling and calculation of the results was predefined. The participants were provided with an uncertainty budget as a GUM Workbench® file as well as a free software license for the duration of the comparison. The agreement of the values of the molar mass (M(Si) = 27.976 942 577 g mol−1) was excellent with ten out of 11 results reported within the range of relative uncertainty of 1 × 10−8 required for the revision of the SI.
- Published
- 2020
22. MAGNETIC PROPERTIES OF ISOTOPICALLY ENRICHED 56Fe
- Author
-
Аlexander Savchenko, Аleksandr Potapov, Yuriy Belozerov, Pavel Mogilnikov, A. D. Bulanov, Sergey Melnikov, M. F. Churbanov, Oleg Troshin, and Igor Belyaev
- Published
- 2020
23. Sources of Carbon Impurities in the Preparation of High-Purity Monoisotopic 28Si by a Hydride Method
- Author
-
O. Yu. Troshin, L. V. Shabarova, A. Yu. Sozin, T.V. Kotereva, V. A. Gavva, A. Yu. Lashkov, A. D. Bulanov, T. G. Sorochkina, Yu. P. Kirillov, M. F. Churbanov, Nickolay Abrosimov, and O. Yu. Chernova
- Subjects
010302 applied physics ,Calcium hydride ,Materials science ,Silicon ,Hydride ,General Chemical Engineering ,Metals and Alloys ,Analytical chemistry ,chemistry.chemical_element ,engineering.material ,01 natural sciences ,010309 optics ,Inorganic Chemistry ,chemistry.chemical_compound ,Polycrystalline silicon ,chemistry ,Impurity ,0103 physical sciences ,Materials Chemistry ,engineering ,Monoisotopic mass ,Pyrolysis ,Carbon - Abstract
This paper examines sources of carbon impurities in polycrystalline monoisotopic 28Si prepared by a hydride method. Analytical data on the concentrations of carbon-containing impurities in volatile silicon compounds (28SiH4 and 28SiH4), process gases (Ar and H2), and polycrystalline 28Si are used to identify the major sources of carbon in the polycrystalline 28Si prepared by the hydride method. These are the starting 28SiH4 and calcium hydride used in 28SiH4 conversion into 28SiH4. The rate of carbon intake into polycrystalline silicon from the apparatus material during the monosilane pyrolysis process does not exceed 9 × 1011 cm–2 h–1. Polycrystalline silicon has been precipitated from monosilane with different concentrations of hydrocarbon impurities. At hydrocarbon concentrations in the range 10–4 to 10–3 mol %, the carbon concentration in the monosilane correlates with that in the silicon obtained from it. High-purity monosilane has been used to prepare polycrystalline 28Si samples with concentrations of carbon impurities in the range (0.8–2.3) × 1015 cm–3. Based on calculations of the carbon impurity distribution along the length of a zone-refined ingot, we examine the effect of the initial carbon concentration in the starting polycrystal on the yield of single-crystal monoisotopic 28Si. Requirements are formulated for the carbon concentration in polycrystalline 28Si which ensure a high yield of single crystals with parameters suitable for metrological applications.
- Published
- 2018
24. Modeling Iron Pentacarbonyl Vaporization Accompanied by Vapor Condensation on a Flowing Down Liquid Film
- Author
-
A. D. Bulanov, Yu. S. Belozerov, Yu. P. Kirillov, V. A. Shaposhnikov, and M. F. Churbanov
- Subjects
Condensed Matter::Quantum Gases ,010302 applied physics ,Materials science ,Vertical tube ,Vapor pressure ,General Chemical Engineering ,Metals and Alloys ,Thermodynamics ,02 engineering and technology ,01 natural sciences ,Iron pentacarbonyl ,law.invention ,Inorganic Chemistry ,chemistry.chemical_compound ,Liquid film ,020401 chemical engineering ,chemistry ,law ,0103 physical sciences ,Vaporization ,Materials Chemistry ,Physics::Atomic Physics ,0204 chemical engineering ,Distillation ,Physics::Atmospheric and Oceanic Physics - Abstract
Using iron pentacarbonyl distillation as an example, we analyze the vaporization process in a closed vaporization–condensation system where vapor condenses on a flowing down liquid film. We jointly analyze the mechanisms behind vaporization, vapor transport, condensation, and flowing of the condensate on the inner surface of a vertical tube. We calculate the thickness of the flowing down liquid film, determine the vaporization coefficient for a closed system using experimentally determined temperature dependences of the vaporization rate and saturated vapor pressure, and present the vaporization rate as a function of the vaporization and condensation temperatures, the radius and height of the condensation tube, and the vaporization area of the still residue.
- Published
- 2018
25. Refractive index spectral dependence, Raman spectra, and transmission spectra of high-purity
- Author
-
Victor A, Lipskiy, Vitaly O, Nazaryants, Tatiana V, Kotereva, Andrei D, Bulanov, Vladimir A, Gavva, Vasily V, Koltashev, Mikhail F, Churbanov, and Victor G, Plotnichenko
- Abstract
The results of the precise measurement of the refractive index of stable germanium isotopes Ge72, Ge73, Ge74, and Ge76 single crystals with high enrichment and a germanium single-crystal Genat of natural isotopic composition with the Fourier-transform interference refractometry method from 1.94 to 20 μm with 0.1 cm
- Published
- 2019
26. Liquid–Vapor Equilibria in the SiCl4–A (A = SiCl4–nFn (n = 1–4) Impurity) Systems
- Author
-
A. D. Bulanov, O. Yu. Troshin, and O. Yu. Chernova
- Subjects
010302 applied physics ,Materials science ,Silicon ,Liquid vapor ,General Chemical Engineering ,Metals and Alloys ,Analytical chemistry ,chemistry.chemical_element ,Conformal map ,02 engineering and technology ,021001 nanoscience & nanotechnology ,01 natural sciences ,Distillation method ,Inorganic Chemistry ,chemistry.chemical_compound ,symbols.namesake ,chemistry ,Impurity ,0103 physical sciences ,Materials Chemistry ,Silicon tetrachloride ,symbols ,Vapor–liquid equilibrium ,Rayleigh scattering ,0210 nano-technology - Abstract
The vapor–liquid separation factors of SiCl4–A (A = SiCl4–nFn (n = 1–4) silicon fluorochloride impurities in silicon tetrachloride have been determined experimentally at 298 K by statically balancing phases. The values obtained for the SiCl4–SiCl3F, SiCl4–SiCl2F2, SiCl4–SiClF3, and SiCl4–SiF4 systems are 4.9 ± 0.8, 8.2 ± 1.2, 29.8 ± 6.1, and 42.0 ± 7.5, respectively. In the SiCl4–SiCl3F system, the vapor–liquid separation factor has also been determined by the Rayleigh distillation method: α = 5.0. The experimental data agree with the vapor–liquid separation factors estimated in conformal solution theory using parameters of the Lennard- Jones potential.
- Published
- 2018
27. Synthesis of 28SiC from 28SiF4 and Methane in Radiofrequency (13.56 MHz) Arc Hydrogen Plasma
- Author
-
R. A. Kornev, Peter Sennikov, A. D. Bulanov, A. M. Potapov, and V. V. Nazarov
- Subjects
010302 applied physics ,Silicon ,Hydrogen ,Analytical chemistry ,chemistry.chemical_element ,010403 inorganic & nuclear chemistry ,01 natural sciences ,Methane ,0104 chemical sciences ,Carbide ,Electric arc ,chemistry.chemical_compound ,chemistry ,0103 physical sciences ,Electrode ,Silicon carbide ,Graphite ,Physical and Theoretical Chemistry - Abstract
Some features of atmospheric-pressure radiofrequency (13.56 MHz) arc discharge and its use for obtaining bulk samples of isotope-enriched silicon carbide via the reaction between SiF4 and methane in a hydrogen medium have been considered. It has been shown that power in this type of discharge is released mainly in the near-electrode regions. The deposition of silicon and graphite occurs in a layer-by-layer mode, so that the product carbide contains up to 40% free carbon; therefore, the process requires optimization. At the same time, the proposed type of RF arc discharge with the product deposition zone localized at the ends of the electrodes makes it possible to avoid not only additional heating of the reactor space and walls, but also the loss of expensive isotope-enriched silicon fluoride.
- Published
- 2018
28. Identification of impurities in tetrakis(trifluorophosphine) nickel using the gas chromatography-mass spectrometry method
- Author
-
О. Iu. Chernova, А. Iu. Sozin, О. Iu. Troshin, T. G. Sorochkina, and A. D. Bulanov
- Subjects
Nickel ,Chromatography ,chemistry ,Impurity ,chemistry.chemical_element ,Gas chromatography–mass spectrometry ,Analytical Chemistry - Published
- 2018
29. Impurity composition of monoisotopic 28SiF4 silicon tetrafluoride
- Author
-
T. G. Sorochkina, A. D. Bulanov, O. Yu. Chernova, and A. Yu. Sozin
- Subjects
chemistry.chemical_classification ,Silicon ,Chemistry ,General Chemical Engineering ,Inorganic chemistry ,Metals and Alloys ,Analytical chemistry ,chemistry.chemical_element ,02 engineering and technology ,010402 general chemistry ,021001 nanoscience & nanotechnology ,Mass spectrometry ,01 natural sciences ,0104 chemical sciences ,Inorganic Chemistry ,chemistry.chemical_compound ,Hydrocarbon ,Impurity ,Materials Chemistry ,Silicon tetrafluoride ,Gas chromatography ,Monoisotopic mass ,Gas chromatography–mass spectrometry ,0210 nano-technology - Abstract
The impurity composition of 28SiF4 has been studied for the first time by gas chromatography/mass spectrometry using gas-adsorption capillary columns. For identification and determination of impurity substances by gas chromatography/mass spectrometry, we have proposed using cryogenic preconcentration of the impurities from 28SiF4. The presence of C2–C4 hydrocarbon impurities and sulfur hexafluoride has been confirmed. We have identified 35 impurity substances in 28SiF4, including linear and branched C5–C8 saturated hydrocarbons, aromatic hydrocarbons, chlorine- and fluorine-containing hydrocarbons, and silicon- and sulfur-containing substances, of which 28 have been detected for the first time.
- Published
- 2017
30. Ultrapurification of iron pentacarbonyl by distillation techniques
- Author
-
Yu. S. Belozerov, M. O. Steshin, A. Yu. Sozin, A. M. Potapov, O. Yu. Chernova, and A. D. Bulanov
- Subjects
010302 applied physics ,Fractional distillation ,chemistry.chemical_classification ,Vacuum distillation ,General Chemical Engineering ,Metals and Alloys ,Analytical chemistry ,Continuous distillation ,02 engineering and technology ,021001 nanoscience & nanotechnology ,01 natural sciences ,Iron pentacarbonyl ,law.invention ,Inorganic Chemistry ,chemistry.chemical_compound ,Hydrocarbon ,chemistry ,Impurity ,law ,0103 physical sciences ,Materials Chemistry ,Metallic impurities ,0210 nano-technology ,Distillation - Abstract
Volatile impurities have been removed from iron pentacarbonyl of natural isotopic composition by vacuum pumping. We have examined the behavior of impurities in the course of fractional distillation of iron pentacarbonyl. As a result of simple distillation, we have obtained an iron pentacarbonyl sample containing on the order of 10–4 mol % C3–C6 hydrocarbon impurities, 10–3 mol % C7–C8 hydrocarbons, and 10–8 to 10–6 wt % metallic impurities. We have estimated the effective separation factor at a distillation rate of 0.021 kg/(m2 s) for a number of impurities in Fe(CO)5.
- Published
- 2017
31. A new generation of 99.999% enriched28Si single crystals for the determination of Avogadro’s constant
- Author
-
A. D. Bulanov, S. V. Filimonov, H.-J. Pohl, Stefan Wundrack, Peter Becker, Nickolay Abrosimov, Axel Pramann, O. N. Godisov, D. G. Aref'ev, D. Nietzold, A. V. Gusev, Horst Bettin, Rainer Stosch, Sabine Zakel, Helge Riemann, P. T. Scheel, V. A. Gavva, A. M. Potapov, M. F. Churbanov, M. Peters, and T.V. Kotereva
- Subjects
Materials science ,Kilogram ,Crystal density ,Silicon ,business.industry ,General Engineering ,chemistry.chemical_element ,02 engineering and technology ,021001 nanoscience & nanotechnology ,01 natural sciences ,Metrology ,010309 optics ,symbols.namesake ,chemistry ,0103 physical sciences ,Avogadro constant ,symbols ,0210 nano-technology ,Constant (mathematics) ,Process engineering ,business ,Chemical purity ,Single crystal - Abstract
A metrological challenge is currently underway to replace the present definition of the kilogram. One prerequisite for this is that the Avogadro constant, N A, which defines the number of atoms in a mole, needs to be determined with a relative uncertainty of better than 2 × 10−8. The method applied in this case is based on the x-ray crystal density experiment using silicon crystals. The first attempt, in which silicon of natural isotopic composition was used, failed. The solution chosen subsequently was the usage of silicon highly enriched in 28Si from Russia. First, this paper reviews previous efforts from the very first beginnings to an international collaboration with the goal of producing a 28Si single crystal with a mass of 5 kg, an enrichment greater than 0.9999 and of sufficient chemical purity. Then the paper describes the activities of a follow-up project, conducted by PTB, to produce a new generation of highly enriched silicon in order to demonstrate the quasi-industrial and reliable production of more than 12 kg of the 28Si material with enrichments of five nines. The intention of this project is also to show the availability of 28Si single crystals as a guarantee for the future realisation of the redefined kilogram.
- Published
- 2017
32. Impurity composition of high-purity isotopically enriched monosilane and monogermane
- Author
-
A. Yu. Sozin, M. F. Churbanov, A. D. Bulanov, T. G. Sorochkina, L. B. Nushtaeva, and O. Yu. Chernova
- Subjects
010302 applied physics ,chemistry.chemical_classification ,Silanes ,General Chemical Engineering ,Inorganic chemistry ,Metals and Alloys ,02 engineering and technology ,021001 nanoscience & nanotechnology ,Mass spectrometry ,01 natural sciences ,Silane ,Inorganic Chemistry ,chemistry.chemical_compound ,chemistry ,Impurity ,Germane ,0103 physical sciences ,Materials Chemistry ,Mass spectrum ,Gas chromatography ,0210 nano-technology ,Alkyl - Abstract
The impurity composition of 28SiH4, 29SiH4, and 30SiH4 silanes and 72GeH4, 73GeH4, 74GeH4, and 76GeH4 germanes isotopically enriched to above 99.9 at % has been studied by gas chromatography/mass spectrometry using capillary adsorption columns. Impurities have been identified by comparing their mass spectra with NIST data and information available in the literature, and by inferring their structure from fragment ions and retention times. We have identified 53 impurity substances in silanes and 42 in germanes: permanent gases; saturated, unsaturated, halogen-containing, and aromatic C1–C9 hydrocarbons; their homologues; alkyl derivatives of silane and germane; chlorogermane; siloxanes; fluorosiloxanes; sulfur compounds; and dioxane. The silicon- and germanium-containing impurities have been shown to be isotopically enriched, as the major component. The detection limits of the impurities are 5 × 10–8 to 3 × 10–5 vol %, comparing well with the best results in the literature.
- Published
- 2017
33. Determination of impurity composition of high-purity germane enriched with 74Ge isotope using gas chromatography-mass spectrometry method
- Author
-
О. Yu. Chernova, А. Yu. Sozin, L. B. Nushtaeva, A. D. Bulanov, T. G. Sorochkina, and V. A. Krylov
- Subjects
chemistry.chemical_compound ,chemistry ,Isotope ,Germane ,Impurity ,Analytical chemistry ,Composition (visual arts) ,Gas chromatography–mass spectrometry ,Analytical Chemistry - Published
- 2017
34. FILTRATION COMBUSTION OF SiF4 AND CaH2 IN VERTICAL FLOW REACTOR
- Author
-
A. Yu. Lashkov, A. D. Bulanov, and O. Yu. Troshin
- Published
- 2019
- Full Text
- View/download PDF
35. Filtration combustion of silicon tetrafluoride and calcium hydride for the preparation of monosilane
- Author
-
A. Yu. Lashkov, O. Yu. Troshin, and A. D. Bulanov
- Subjects
Calcium hydride ,Order of reaction ,General Chemical Engineering ,Inorganic chemistry ,Metals and Alloys ,02 engineering and technology ,Activation energy ,010402 general chemistry ,021001 nanoscience & nanotechnology ,Kinetic energy ,Combustion ,01 natural sciences ,0104 chemical sciences ,law.invention ,Inorganic Chemistry ,chemistry.chemical_compound ,Reaction rate constant ,chemistry ,law ,Materials Chemistry ,Silicon tetrafluoride ,0210 nano-technology ,Filtration - Abstract
We have studied reaction between silicon tetrafluoride and calcium hydride in a vertical flow reactor, which proceeds as combustion in filtration mode. The principal kinetic characteristics of the reaction between SiF4 and CaH2 in a counterpropagating wave have been determined: reaction order n = 1, rate constant k = 0.38 ± 0.05 s–1, and activation energy Ea = 17 ± 2 kJ/mol.
- Published
- 2016
36. Isotope analysis of 72GeH4, 73GeH4, 74GeH4, and 76GeH4 monogermanes by inductively-coupled plasma high-resolution mass spectrometry (ICP–MS)
- Author
-
A. E. Kurganova, A. D. Bulanov, O. Yu. Troshin, S. M. Zyryanov, and A. M. Potapov
- Subjects
Isotope ,Chemistry ,Stable isotope ratio ,010401 analytical chemistry ,Analytical chemistry ,02 engineering and technology ,Thermal ionization mass spectrometry ,021001 nanoscience & nanotechnology ,Mass spectrometry ,01 natural sciences ,0104 chemical sciences ,Analytical Chemistry ,Isotopic labeling ,Monoisotopic mass ,Inductively coupled plasma ,0210 nano-technology ,Inductively coupled plasma mass spectrometry - Abstract
A possibility of using inductively-coupled plasma high-resolution mass spectrometry for the isotope analysis of monogermanes enriched with isotopes 72, 73, 74, and 76 has been studied. The effects of isobaric and polyatomic interferences in the spectrum of germanium isotopes have been discussed. It has been shown that the signal intensities of i GeH+ ions formed in the inductively coupled plasma are 0.00001–0.0001 of the intensity of the i Ge+ signal. This can result in the overestimation of the found concentration of an isotope with a higher mass number next to the main isotope in recording spectra in the low and medium resolution mode. Approaches ensuring the determination of the isotope composition of highly-enriched monogermanes with the range of isotope concentrations extending five orders of magnitude have been proposed.
- Published
- 2016
37. Epitaxially Grown Monoisotopic Si, Ge, and Si1–x Ge x Alloy Layers: Production and Some Properties
- Author
-
A. P. Detochenko, A. V. Nezhdanov, M. N. Drozdov, A. D. Bulanov, D. V. Shengurov, V. A. Gavva, M. V. Stepikhova, V. G. Shengurov, S. A. Denisov, V. Yu. Chalkov, Nickolay Abrosimov, Helge Riemann, Aleksandr Mashin, V. N. Trushin, and A. A. Ezhevskii
- Subjects
Photoluminescence ,Materials science ,010401 analytical chemistry ,Doping ,Alloy ,Analytical chemistry ,02 engineering and technology ,engineering.material ,021001 nanoscience & nanotechnology ,Condensed Matter Physics ,Epitaxy ,Mass spectrometry ,01 natural sciences ,Atomic and Molecular Physics, and Optics ,0104 chemical sciences ,Electronic, Optical and Magnetic Materials ,symbols.namesake ,Crystallography ,symbols ,engineering ,Sublimation (phase transition) ,Monoisotopic mass ,0210 nano-technology ,Raman spectroscopy - Abstract
The technology of the growth of Si, Ge, and Si1–xGex layers by molecular-beam epitaxy with the use of a sublimation source of monoisotopic 30Si or 28Si and/or gas sources of monogermane 74GeH4 is demonstrated. All of the epitaxial layers are of high crystal quality. The secondary-ion mass spectroscopy data and Raman data suggest the high isotopic purity and structural perfection of the 30Si, 28Si, 74Ge, and 30Si1–x74Gex layers. The 30Si layers doped with Er exhibit an efficient photoluminescence signal.
- Published
- 2016
38. 99.992 % $^{28}$Si CVD-grown epilayer on 300 mm substrates for large scale integration of silicon spin qubits
- Author
-
B. Bertrand, Jean-Michel Hartmann, A. D. Bulanov, M. F. Churbanov, Marc Sanquer, V. Mazzocchi, M. N. Drozdov, Jean-Paul Barnes, Petr G. Sennikov, Louis Hutin, Commissariat à l'énergie atomique et aux énergies alternatives - Laboratoire d'Electronique et de Technologie de l'Information (CEA-LETI), Direction de Recherche Technologique (CEA) (DRT (CEA)), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA), Laboratoire de Transport Electronique Quantique et Supraconductivité (LaTEQS), PHotonique, ELectronique et Ingénierie QuantiqueS (PHELIQS), Université Grenoble Alpes [2016-2019] (UGA [2016-2019])-Institut de Recherche Interdisciplinaire de Grenoble (IRIG), Direction de Recherche Fondamentale (CEA) (DRF (CEA)), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Direction de Recherche Fondamentale (CEA) (DRF (CEA)), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Grenoble Alpes [2016-2019] (UGA [2016-2019])-Institut de Recherche Interdisciplinaire de Grenoble (IRIG), and European Project: 688539,H2020,H2020-ICT-2015,MOS-QUITO(2016)
- Subjects
Materials science ,Silicon ,chemistry.chemical_element ,FOS: Physical sciences ,02 engineering and technology ,Epitaxy ,01 natural sciences ,Inorganic Chemistry ,0103 physical sciences ,Materials Chemistry ,Isotopes of silicon ,Quantum computer ,010302 applied physics ,Condensed Matter - Materials Science ,Spins ,Dopant ,business.industry ,Materials Science (cond-mat.mtrl-sci) ,021001 nanoscience & nanotechnology ,Condensed Matter Physics ,Quantum technology ,chemistry ,Quantum dot ,[PHYS.COND.CM-MS]Physics [physics]/Condensed Matter [cond-mat]/Materials Science [cond-mat.mtrl-sci] ,Optoelectronics ,0210 nano-technology ,business - Abstract
Silicon-based quantum bits with electron spins in quantum dots or nuclear spins on dopants are serious contenders in the race for quantum computation. Added to process integration maturity, the lack of nuclear spins in the most abundant $^{28}$silicon isotope host crystal for qubits is a major asset for this silicon quantum technology. We have grown $^{28}$silicon epitaxial layers (epilayers) with an isotopic purity greater than 99.992 % on 300mm natural abundance silicon crystals. The quality of the mono-crystalline isotopically purified epilayer conforms to the same drastic quality requirements as the natural epilayers used in our pre-industrial CMOS facility. The isotopically purified substrates are now ready for the fabrication of silicon qubits using a state-of-the-art 300 mm Si CMOS-foundries equipment and processes, Comment: 7 pages, 7 figures
- Published
- 2018
- Full Text
- View/download PDF
39. Liquid-vapor equilibria in GeF4-A (A = C1-C4 alkane impurity) systems
- Author
-
O. Yu. Troshin, A. N. Kolesnikov, T. G. Sorochkina, and A. D. Bulanov
- Subjects
Alkane ,chemistry.chemical_classification ,Chemistry ,Vapor pressure ,General Chemical Engineering ,Inorganic chemistry ,Metals and Alloys ,Analytical chemistry ,Germanium tetrafluoride ,Inorganic Chemistry ,chemistry.chemical_compound ,Impurity ,Propane ,Vaporization ,Materials Chemistry ,Isobutane ,Antoine equation - Abstract
The liquid–vapor separation factors in dilute solutions of methane, ethane, propane, n-butane, and isobutane in germanium tetrafluoride have been determined experimentally at 295 K by statically balancing phases. The measured temperature-dependent saturated vapor pressure over liquid germanium tetrafluoride in the range 260–300 K can be represented by the Antoine equation: log P (atm) = 5.2–1200/T. We have calculated the enthalpies of vaporization and fusion of germanium tetrafluoride:ΔH v 0= 22.9 kJ/mol and ΔH m 0(GeF4) = 8.0 kJ/mol.
- Published
- 2015
40. Erratum: Determination of Low Loss in Isotopically Pure Single Crystal 28Si at Low Temperatures and Single Microwave Photon Energy
- Author
-
Nikita Kostylev, Maxim Goryachev, Andrey D. Bulanov, Vladimir A. Gavva, and Michael E. Tobar
- Subjects
Multidisciplinary - Abstract
Scientific Reports 7: Article number: 44813; published online: 20 March 2017; updated: 20 September 2017. The original version of this Article contained typographical errors in the Abstract. “Whispering Gallery Mode (WGM) analysis revealed large Quality Factors of order 2 × 106 (dielectric loss ~5 ×10−7) at high powers, degrading to 7 × 10−5 (dielectric loss ~1.
- Published
- 2017
41. Determination of Low Loss in Isotopically Pure Single Crystal 28Si at Low Temperatures and Single Microwave Photon Energy
- Author
-
Nikita Kostylev, Maxim Goryachev, A. D. Bulanov, V. A. Gavva, and Michael E. Tobar
- Subjects
Quantum Physics ,Multidisciplinary ,Materials science ,Photon ,Condensed Matter - Mesoscale and Nanoscale Physics ,Spin transition ,Physics::Optics ,FOS: Physical sciences ,02 engineering and technology ,Dielectric ,Photon energy ,021001 nanoscience & nanotechnology ,01 natural sciences ,Molecular physics ,Article ,Crystal ,Paramagnetism ,0103 physical sciences ,Mesoscale and Nanoscale Physics (cond-mat.mes-hall) ,Dielectric loss ,Erratum ,010306 general physics ,0210 nano-technology ,Quantum Physics (quant-ph) ,Single crystal - Abstract
The low dielectric losses of an isotropically pure single crystal $^{28}$Si sample were determined at a temperature of 20 mK and at powers equivalent to that of a single photon. Whispering Gallery Mode (WGM) analysis revealed large Quality Factors of order $2\times10^6$ (dielectric loss $\sim 5\times10^{-7}$) at high powers, degrading to $7\times10^5$ (dielectric loss $\sim 1.4\times10^{-6}$) at single photon energy. A very low-loss narrow line width paramagnetic spin flip transition was detected with extreme sensitivity in $^{28}$Si, with very small concentration below $10^{11}$~cm$^{-3}$ (less than 10 parts per trillion) and g-factor of $1.995\pm0.008$. Such determination was only possible due to the low dielectric photonic losses combined with the long lifetime of the spin transition (low magnetic loss), which enhances the magnetic AC susceptibility. Such low photonic loss at single photon energy combined with the narrow line width of the spin ensemble, indicate that single crystal $^{28}$Si could be an important crystal for future cavity QED experiments., Comment: 5 pages, 5 figures
- Published
- 2017
- Full Text
- View/download PDF
42. Monogermanes 74GeH4 and 73GeH4 of high isotopic and chemical purity
- Author
-
O. Yu. Troshin, M. F. Churbanov, A. V. Gusev, A. Yu. Lashkov, A. D. Bulanov, S. A. Adamchik, and V. A. Lipskii
- Subjects
Chemistry ,Radiochemistry ,General Chemistry ,Chemical purity - Published
- 2014
43. First high–resolution analysis of the 2ν1(A1) and ν1+ν3(F2) interacting states of 72GeH4 and 73GeH4
- Author
-
Elena Sergeevna Bekhtereva, O.N. Ulenikov, M.A. Koshelev, A. D. Bulanov, Olga Vasilievna Gromova, Claude Leroy, N.I. Raspopova, I.A. Velmuzhova, A.V. Kuznetsov, and Peter Sennikov
- Subjects
Physics ,High resolution analysis ,Radiation ,010504 meteorology & atmospheric sciences ,Analytical chemistry ,Fourier transform spectrometers ,High resolution ,01 natural sciences ,Atomic and Molecular Physics, and Optics ,Spectral line ,chemistry.chemical_compound ,chemistry ,Germane ,Isotopologue ,Spectroscopy ,0105 earth and related environmental sciences ,Line (formation) - Abstract
The spectra of germane 72GeH4 and 73GeH4 enriched up to 99.9 % were recorded with high resolution (0.003 cm − 1 ) at different pressures with the Bruker IFS 125HR Fourier transform spectrometer (Nizhny Novgorod, Russia). The region of 4020–4260 cm − 1 , where the 2ν1(A1) and ν 1 + ν 3 ( F 2 ) bands are located, was theoretically analyzed. The 2025 and 1774 transitions with J max = 21 were assigned to these bands of the 72GeH4 and 73GeH4 species. Rotational, centrifugal distortion, tetrahedral splitting, and interaction parameters of the (2000, A1) and (1010, F2) vibrational states were determined from the fit of experimental line positions of both isotopologues. The obtained sets of 13/13 fitted parameters reproduce the initial 2025/1774 experimental line positions with a d rms = 2.9 × 10 − 4 cm − 1 and d rms = 2.7 × 10 − 4 cm − 1 (for 72GeH4 and 73GeH4, respectively).
- Published
- 2019
44. Refractive index spectral dependence, Raman spectra, and transmission spectra of high-purity 72Ge, 73Ge, 74Ge, 76Ge, and natGe single crystals
- Author
-
V. V. Koltashev, Victor G. Plotnichenko, T.V. Kotereva, V. A. Gavva, Victor A. Lipskiy, Andrei D. Bulanov, V O Nazaryants, and M. F. Churbanov
- Subjects
Materials science ,Isotopes of germanium ,business.industry ,Analytical chemistry ,Infrared spectroscopy ,chemistry.chemical_element ,Germanium ,01 natural sciences ,Atomic and Molecular Physics, and Optics ,Spectral line ,010309 optics ,symbols.namesake ,Optics ,chemistry ,0103 physical sciences ,Dispersion (optics) ,symbols ,Electrical and Electronic Engineering ,Raman spectroscopy ,business ,Engineering (miscellaneous) ,Refractometry ,Refractive index - Abstract
The results of the precise measurement of the refractive index of stable germanium isotopes Ge72, Ge73, Ge74, and Ge76 single crystals with high enrichment and a germanium single-crystal Genat of natural isotopic composition with the Fourier-transform interference refractometry method from 1.94 to 20 μm with 0.1 cm−1 resolution and accuracy of 2×10−5 to 1×10−4 are shown. The content of 72 impurities measured by the mass spectrometric method was below 10−5–10−6 wt. %. Oxygen and carbon concentrations measured by IR spectroscopy in all crystals are within 5×1015 cm−3. All germanium crystals have a hole conductivity with specific electric resistivity of 45–50 Ohm×cm. The coefficients of the generalized Cauchy dispersion function approximating the experimental refractive index values all over the measuring range are given. The transmission and Raman spectra are also given.
- Published
- 2019
45. Monoisotopic varieties of silicon and germanium with a high chemical and isotopic purity
- Author
-
M. F. Churbanov, A. M. Potapov, A. D. Bulanov, and A. V. Gusev
- Subjects
Thermal conductivity ,Isotope ,Silicon ,Electrical resistivity and conductivity ,Chemistry ,Impurity ,Analytical chemistry ,chemistry.chemical_element ,Germanium ,General Chemistry ,Monoisotopic mass ,Heat capacity - Abstract
We presented the results on the preparation of high-purity monoisotopic varieties of silicon and germanium. The process involves the separation of isotopes in the form of SiF4 and GeH4 by centrifugation, ultrapurification of volatile compounds, and preparation of poly and single crystals. The attained degree of isotopic and chemical purities of single crystals obtained was shown. The content of the main isotope in the single crystals of 28Si is >99.99% and those in the single crystals of 29Si and 30Si are >99.9%. The specific resistivity of the 28Si single crystals is ∼1 kOhm cm and those of 29Si and 30Si are about 100–150 Ohm cm. The samples of the 76Ge single crystals have the main isotope content of >88 at.% and the difference concentration of electrochemically active impurities of 5·1010 cm−3. The main isotope content in the 74Ge polycrystal is 99.93 at.%. The optical and thermophysical properties of the isotope-enriched silicon and germanium single crystals were measured, which suggest a significant effect of the isopotic composition on thermal capacity, thermal conductivity, luminiscence, and light absorption.
- Published
- 2013
46. Vibrational spectra of monoisotopic SiH4 and GeH4 in low-temperature matrices
- Author
-
I.A. Velmuzhova, K. F. Savvateev, T. D. Kolomiitsova, Dmitrii N. Shchepkin, Peter Sennikov, Konstantin G. Tokhadze, and A. D. Bulanov
- Subjects
Materials science ,Absorption spectroscopy ,Analytical chemistry ,Matrix isolation ,Spectral bands ,Atomic and Molecular Physics, and Optics ,Spectral line ,Electronic, Optical and Magnetic Materials ,Solid nitrogen ,chemistry.chemical_compound ,Nuclear magnetic resonance ,chemistry ,Germane ,Molecular symmetry ,Monoisotopic mass - Abstract
IR absorption spectra of monoisotopic 28SiH4 and 76GeH4 are studied in Ar and N2 matrices at 10 K. It is shown that the absorption spectra of silane and germane are similar in the regions of the stretching ν3 and bending ν4 vibrations. Four groups of bands can be separated out in the spectra of each molecule: (1) narrow bands characteristic of the matrix isolation studies, (2) broad bands, (3) diffuse absorption with a large value of the spectral moment M 2 * the intensity of which increases upon annealing, and (4) bands of dimers the intensity of which increases quadratically with concentration. The spectra of 28SiH4 and 76GeH4 in nitrogen matrices contain a triplet in the stretching region and a doublet in the bending region, which is explained by the change in the molecular symmetry from T d to C 3V on passage from the gas phase to solid nitrogen.
- Published
- 2012
47. Determination of impurities in germanium tetrafluoride by IR spectroscopy and gas chromatography
- Author
-
Peter Sennikov, T. G. Sorochkina, V. A. Krylov, and A. D. Bulanov
- Subjects
Hydrogen ,Silicon ,General Chemical Engineering ,Inorganic chemistry ,Metals and Alloys ,Analytical chemistry ,chemistry.chemical_element ,Infrared spectroscopy ,Germanium tetrafluoride ,Sulfur ,Inorganic Chemistry ,chemistry.chemical_compound ,chemistry ,Impurity ,Materials Chemistry ,Gas chromatography ,Carbon - Abstract
Using high-resolution Fourier-transform IR spectroscopy and gas chromatography, we have identified more than 20 impurity species, in concentrations from 10−1 to 10−5 vol %, in GeF4 samples of different isotopic compositions. The germanium tetrafluoride samples are shown to contain C1–C4 hydrocarbons; hydrogen, carbon, silicon, and sulfur fluorides; fluorogermanes; fluorosilanes; and carbon and nitrogen oxides.
- Published
- 2010
48. Mechanically activated synthesis of monosilane by the reaction of calcium hydride with silicon tetrafluoride
- Author
-
A. D. Bulanov, V. S. Mikheev, O. Yu. Troshin, and A. Yu. Lashkov
- Subjects
chemistry.chemical_compound ,Calcium hydride ,Chemistry ,General Chemical Engineering ,Inorganic chemistry ,Silicon tetrafluoride ,General Chemistry ,Grinding - Abstract
Possibility of performing a mechanically activated synthesis of pure monosilane by the reaction of calcium hydride with silicon tetrafluoride in a rotating flow-through reactor containing milling bodies was analyzed. A number of operation parameters of the grinding reactor were theoretically evaluated and experimentally determined.
- Published
- 2010
49. Isotopic fingerprints of gold-containing luminescence centers in 28Si
- Author
-
I.D. Kaliteevski, K. Saeedi, A. V. Gusev, Karl Johnston, H.-J. Pohl, H. Riemann, A. D. Bulanov, M. L. W. Thewalt, T. Sekiguchi, M. F. Churbanov, O. N. Godisov, M. Steger, Nickolay Abrosimov, Peter Becker, A. Yang, and Martin O. Henry
- Subjects
Photoluminescence ,Materials science ,Silicon ,Stable isotope ratio ,chemistry.chemical_element ,Crystal structure ,Condensed Matter Physics ,Crystallographic defect ,Electronic, Optical and Magnetic Materials ,Crystallography ,Transition metal ,chemistry ,Isotopes of silicon ,Electrical and Electronic Engineering ,Luminescence - Abstract
We have recently shown that the dramatic reduction in linewidth of many deep luminescence centers in highly enriched 28 Si can lead to the observation of isotopic fingerprints, revealing not only that a specific element is involved in the defect complex, but also the number of atoms of that element. This has led to many surprises regarding the actual constituents of supposedly well known luminescence centers, as well as the discovery of new members of a family of four-atom centers where the constituents can be chosen from Cu, Ag, Au and Li. Obtaining the isotopic fingerprint of Au is problematic, since only 197 Au is stable, but we have now used the relatively long-lived 195 Au to reveal the presence, and the number, of Au atoms in several of these centers. We find a series of four-atom centers containing one Au plus Cu and/or Li. Surprisingly, the Au isotopic fingerprint also reveals a series of five-atom centers containing a single Au plus Cu and/or Li. Further evidence for the ubiquity of these four- and five-atom defects is provided by two previously observed Pt-related centers, with luminescence at 884 and 777 meV, which are present in these samples due to the decay of 195 Au to 195 Pt. In addition to Pt, these centers are found to contain three and four Cu atoms, respectively.
- Published
- 2009
50. High-purity silicon isotopes 28Si, 29Si, and 30Si
- Author
-
A. V. Gusev and A. D. Bulanov
- Subjects
Silicon ,General Chemical Engineering ,Radiochemistry ,Metals and Alloys ,Analytical chemistry ,chemistry.chemical_element ,Heat capacity ,Silane ,Isotope separation ,law.invention ,Inorganic Chemistry ,Monocrystalline silicon ,chemistry.chemical_compound ,chemistry ,law ,Materials Chemistry ,Isotopes of silicon ,Monoisotopic mass ,Boron - Abstract
The current status of the problem of obtaining high-purity silicon isotopes 28Si, 29Si, and 30Si is analyzed. The scheme of obtaining monoisotopic silicon includes the stages of isotope separation in the form SiF4, synthesis and deep purification of isotopically enriched silane, obtaining polycrystalline silicon-28,-29, and-30, and growing monocrystals. The basic problems and methods of their solution in the synthesis and deep purification of silane and obtaining poly-and monocrystals of isotopically enriched silicon are discussed. Data characterizing the achieved level of chemical and isotopic purity of high-purity monocrystals of silicon-28 with a main isotope content of more than 99.99% and silicon-29 and silicon-30 with isotopic purity higher than 99% are presented. In monocrystalline 28Si, the boron content was 4.5 × 1013, the phosphorus content was 5 × 1011, the carbon and oxygen contents were
- Published
- 2008
Catalog
Discovery Service for Jio Institute Digital Library
For full access to our library's resources, please sign in.