65 research outputs found
Experiment for Testing Special Relativity Theory
An experiment aimed at testing special relativity via a comparison of the
velocity of a non matter particle (annihilation photon) with the velocity of
the matter particle (Compton electron) produced by the second annihilation
photon from the decay Na-22(beta^+)Ne-22 is proposed.Comment: 7 pages, 1 figure, Report on the Conference of Nuclear Physics
Division of Russian Academy of Science "Physics of Fundamental Interactions",
ITEP, Moscow, November 26-30, 200
APPLICATIONS OF UV-LIGA AND GRAYSCALE LITHOGRAPHY FOR DISPLAY TECHNOLOGIES
In the article MEMS technologies for display production and application presented. UV-LIGA and greyscale lithography based on SU-8 resist approaches were shown. Methods, technologies and structures of heterogeneous materials with soft magnetic properties, pros and cons are discussed. Unique specific parameters of soft magnetic composite material were achieved: magnetic induction of saturation – 2,1 Т, working frequency range – up to 1 MHz, permeability – up to 3000, total loss – 8 W/kg, Curie temperature – above 800 ºС. Electroplating allows deposition of soft magnetic alloys on the conductive substrate. Metals like Fe, Ni, Co with additives like B, P were used to get the best soft magnetic properties. Special codeposition process was developed to allow insertion of soft magnetic composite powder filaments into soft magnetic matrix formed during. It allows developing magnetic micromotors for display production. Simulation of the hybrid step micromotors was carried out in Ansys Maxwell 19. It was demonstrated that it is possible to get 10 mN m tourqe under 25 μm rotor-stator air gap. Only presented microtechnologies can provide such accuracy of the mciromotors elements. As for greyscale photolithography, special grey mask were developed and it was demonstrated the possibility to produce controllable real 3D relief on the SU-8 photoresist. Thus, microtechnologies should be integrated into display technology to provide cost effective production and advanced properties of final products.In the article MEMS technologies for display production and application presented. UV-LIGA and greyscale lithography based on SU-8 resist approaches were shown. Methods, technologies and structures of heterogeneous materials with soft magnetic properties, pros and cons are discussed. Unique specific parameters of soft magnetic composite material were achieved: magnetic induction of saturation – 2,1 Т, working frequency range – up to 1 MHz, permeability – up to 3000, total loss – 8 W/kg, Curie temperature – above 800 ºС. Electroplating allows deposition of soft magnetic alloys on the conductive substrate. Metals like Fe, Ni, Co with additives like B, P were used to get the best soft magnetic properties. Special codeposition process was developed to allow insertion of soft magnetic composite powder filaments into soft magnetic matrix formed during. It allows developing magnetic micromotors for display production. Simulation of the hybrid step micromotors was carried out in Ansys Maxwell 19. It was demonstrated that it is possible to get 10 mN m tourqe under 25 μm rotor-stator air gap. Only presented microtechnologies can provide such accuracy of the mciromotors elements. As for greyscale photolithography, special grey mask were developed and it was demonstrated the possibility to produce controllable real 3D relief on the SU-8 photoresist. Thus, microtechnologies should be integrated into display technology to provide cost effective production and advanced properties of final products
Applications of UV-LIGA and grayscale lithography for display technologies
In the article MEMS technologies for display production and application presented. UV-LIGA
and greyscale lithography based on SU-8 resist approaches were shown. Methods, technologies and structures of heterogeneous materials with soft magnetic properties, pros and cons are discussed. Unique specific parameters of soft magnetic composite material were achieved: magnetic induction of saturation – 2,1 Т, working frequency range – up to 1 MHz, permeability – up to 3000, total loss – 8 W/kg, Curie temperature – above 800 єС. Electroplating allows deposition of soft magnetic alloys on the conductive substrate. Metals like Fe, Ni, Co with additives like B, P were used to get the best soft magnetic properties. Special codeposition process was developed to allow insertion of soft magnetic composite powder filaments into soft magnetic matrix formed during. It allows developing magnetic micromotors for display production. Simulation of the hybrid step micromotors was carried out in Ansys Maxwell 19. It was demonstrated that it is possible to get 10 mN m tourqe under 25 μm rotor-stator air gap. Only presented microtechnologies can provide such accuracy of the mciromotors elements. As for greyscale photolithography, special grey mask were developed and it was demonstrated the possibility to produce controllable real 3D relief on the SU-8 photoresist. Thus, microtechnologies should be integrated into display technology to provide cost effective production and advanced properties of final products
Электрические свойства композитов на основе порошков железа, капсулированных оксидным покрытием
The electrical characteristics of composite materials based on iron powders ASC 100.29 (Sweden) were investigated. The surface of powders is encapsulated by an insulating ferrite coating. The conductivity and the thermopower were studied, the cores were made by the pressing method, and then the samples were cut from the cores. The results show that the decrease in the electrical resistance with increasing temperature is due to a change in the contact between the grains in the sample. A change in the boundaries between grains (or domains) creates the conditions for formation of a new magnon, which affects the thermopower coefficient value. The research results can be used in the synthesis of composites with specified electromagnetic characteristics for practical applications.Исследованы электрические характеристики композиционных материалов на основе порошков железа ASC 100.29 (Швеция). Поверхность порошков капсулирована изоляционным ферритным покрытием. Для проведения исследований удельной электропроводности и термоЭДС методом прессования изготавливались сердечники, из которых вырезались образцы. Результаты показывают, что уменьшение величины электросопротивления с ростом температуры обусловлено изменением контакта между зернами в образце. Изменение границ между зернами (или доменами) создает условия образования нового магнона, что оказывает влияние на величину коэффициента термоЭДС. Результаты исследований могут быть использованы при синтезе композитов с заданными электромагнитными характеристиками для практических применений
Electromagnetic MEMS motors for display technologies
The fourth revolution of the industry is powered by a wide range breakthrough, new technology, innovative ideas and creative activities. All these things were naturally born, mostly, by the
interdisciplinary science and technology. Soft magnetic composites are the bright example of the
different technologies integration to get final commercial technologies to get the final products
with enhanced properties. Micro displacement and micro positioning became a very important factor for
new display technologies such as inkjet, 3D printing, nanoimprint. New generation of technologies allows
increasing productivity and improving quality. MEMS micromotors are the core of such instruments for
display production
Strong fragmentation of low-energy electromagnetic excitation strength in Sn
Results of nuclear resonance fluorescence experiments on Sn are
reported. More than 50 transitions with MeV were
detected indicating a strong fragmentation of the electromagnetic excitation
strength. For the first time microscopic calculations making use of a complete
configuration space for low-lying states are performed in heavy odd-mass
spherical nuclei. The theoretical predictions are in good agreement with the
data. It is concluded that although the E1 transitions are the strongest ones
also M1 and E2 decays contribute substantially to the observed spectra. In
contrast to the neighboring even Sn, in Sn the
component of the two-phonon quintuplet built on top of
the 1/2 ground state is proved to be strongly fragmented.Comment: 4 pages, 3 figure
Search for the electric dipole excitations to the multiplet in Sn
The odd-mass Sn nucleus was investigated in nuclear resonance
fluorescence experiments up to an endpoint energy of the incident photon
spectrum of 4.1 MeV at the bremsstrahlung facility of the Stuttgart University.
More than 50 mainly hitherto unknown levels were found. From the measurement of
the scattering cross sections model independent absolute electric dipole
excitation strengths were extracted. The measured angular distributions
suggested the spins of 11 excited levels. Quasi-particle phonon model
calculations including a complete configuration space were performed for the
first time for a heavy odd-mass spherical nucleus. These calculations give a
clear insight in the fragmentation and distribution of the , , and
excitation strength in the low energy region. It is proven that the
component of the two-phonon quintuplet built on
top of the ground state is strongly fragmented. The theoretical
calculations are consistent with the experimental data.Comment: 10 pages, 5 figure
Магнитокалорические свойства кристалла Mn0,99Fe0,01As
The Stockbargard – Bridgman method yielded single crystals Mn0.99Fe0.01As. The effect of an external magnetic field with an intensity of up to 10 T on phase transitions in the single crystal Mn0.99Fe0.01As is studied. It is established that the magnetostructural phase transition in Mn0.99Fe0.01As is accompanied by a change in the entropy ΔSm, which is due to the transformation of the crystal structure. At temperatures above the temperature of the magnetostructural transition Tu = 290 K, the existence of an unstable magnetic structure is obtained. The magnetocaloric characteristics of the material under study are determined by an indirect calculation method based on the Maxwell thermodynamic relations and the Clapeyron – Clausius equation.Методом Стокбаргера – Бриджмена были получены монокристаллы Mn0,99Fe0,01As. Исследовано влияние внешнего магнитного поля напряженностью до 10 Тл на фазовые переходы в монокристалле Mn0,99Fe0,01As. Установлено, что магнитоструктурный фазовый переход в Mn0,99Fe0,01As сопровождается изменением энтропии ΔSm, что обусловлено трансформацией кристаллической структуры. При температуре выше температуры магнитоструктурного перехода Tu = 290 К выявлено существование нестабильной магнитной структуры. Магнитокалорические характеристики исследуемого материала определялись косвенным методом расчета на основе термодинамических соотношений Максвелла и уравнения Клапейрона – Клаузиуса
Магнитомягкие композиты на основе порошков железа для создания компонентов двухстаторного комбинированного электродвигателя
An experimental prototype of electric motor on permanent (FeNdB) magnets with switchable magnetic flux with two sectioned stators and a rotor using SMC material based on encapsulated metal powders has been developed. The method of manufacture of magnetic cores by powder metallurgy method on the basis of magnetically soft encapsulated titanium dioxide composites has been developed, including computer modeling of magnetic cores components, creation of tooling for their manufacture by pressing and selection of technological modes of pressing. Press set for manufacturing stator components by pressing in the form of a mold was made of hardened 5XHB steel. With its use magnetic components for twostator combined electric motor are pressed. The main electromagnetic characteristics of the components were measured with an express magnetometer. Complex studies showed that the magnetic components have sufficient strength and the necessary electromagnetic characteristics to create a two-stator combined electric motor of this type. An experimental sample of electric motor with maximum power of 15 kW was created on the basis of manufactured magnetic components. Advantages of composite material over electrical steel and other soft magnetic alloys allow providing their wider application in electric machines in order to increase specific power at high speed of rotation with less losses.Разработан экспериментальный образец электродвигателя с переключаемым магнитным потоком с двумя секционированными статорами и ротором на постоянных (FeNdB) магнитах с применением SMC-материала на основе капсулированных металлических порошков. Создана методика изготовления магнитопроводов на основемагнитомягких капсулированных диоксидом титана композитов методом порошковой металлургии, включающая в себя компьютерное моделирование компонентов магнитопроводов, создание оснастки для их изготовления методом прессования и выбор технологических режимов прессования. Оснастка для компонентов статора методом прессования в виде пресс-формы изготовлена из закаленной стали 5ХHB. С ее применением спрессованы магнитныекомпоненты для двухстаторного комбинированного электродвигателя. Основные электромагнитные характеристики компонентов измерены с помощью экспресс-магнетометра. Комплексные исследования показали, что магнитные компоненты обладают достаточной прочностью и необходимыми электромагнитными характеристиками длясоздания двухстаторного комбинированного данного типа электродвигателя. На основе изготовленных магнитных компонентов создан экспериментальный образец электродвигателя с максимальной расчетной мощностью 15 кВт. Преимущества композиционного материала перед электротехнической сталью и другими магнитомягкими сплавами позволяют обеспечить более широкое их применение в электрических машинах с целью повышения удельной мощности при высокой скорости вращения с меньшими потерями
Исследование влияния условий синтеза на магнитные характеристики композиционных материалов на основе порошков железа
The influence of synthesis conditions on the magnetic characteristics of composite materials based on iron powders ASC 100.29 (Sweden) and LiaoNing (China) is investigated. The surface of metallic iron powders is encapsulated by an insulating ferrite coating, consisting of iron oxides and phosphides. The synthesis was carried out at a temperature of 150 °C from a gaseous medium in a special reactor at a pressure of 1 atm. Insulating oxide coatings were applied both to the initial iron powder without treatment, and to previously annealed powders in an inert atmosphere and in a mixture of hydrogen-argon. To conduct studies of magnetic characteristics, cores in the form of rings were made by pressing method. The dependence of induction vs. magnitude of the magnetic field, magnetization reversal losses (hysteresis losses) in the full and in the private loop were recorded by an express magnetometer. The value of losses was calculated by the hysteresis loops area. The results show that composite low-frequency magnetic materials based on metallic iron ASC 100.29 and LiaoNing powders have similar values of magnetic parameters – almost identical B = f(H) dependencies, but the magnetization reversal losses for ASC 100.29 are significantly lower than for LiaoNing powder under equal insulating coatings synthesis conditions. It is possible to use such materials as magnetic cores in various electrical devices, such as cores of high-frequency transformers and a number of electrical machines. Since such materials can operate at frequencies from 1 kHz and higher, this will significantly reduce the overall dimensions and increase the efficiency of electrical products.Исследовано влияние условий синтеза на магнитные характеристики композиционных материалов на основе железных порошков ASC 100.29 (Швеция) и LiaoNing (Китай). Поверхность частиц порошков металлического железа капсулирована изоляционным ферритным покрытием, состоящим из окислов железа и фосфидов. Синтез проводился при температуре 150 °С из газовой среды в специальном реакторе при давлении 1 атм. Изолирующие оксидные покрытия наносились как на частицы исходных порошков железа без обработки, так и на предварительно отожженные порошки в инертной атмосфере и в смеси водород-аргон. Для проведения исследований магнитных характеристик методом прессования изготавливались сердечники в виде колец. Зависимость индукции от величины магнитного поля, потери на перемагничивание (гистерезисные потери) по полной и по частной петле регистрировались на экспресс-магнитометре. Величина потерь рассчитывалась по площади петли гистерезиса. Результаты показывают, что композиционные низкочастотные магнитные материалы на основе порошков металлического железа ASC 100.29 (Швеция) и LiaoNing (Китай) имеют близкие по величине магнитные параметры – практически идентичные зависимости В = f(Н), однако потери на перемагничивание для ASC 100.29 существенно ниже, чем для LiaoNing порошка, при равных условиях синтеза изоляционных покрытий. Возможно использование таких материалов в качестве магнитопроводов в электротехнических устройствах, таких как сердечники высокочастотных трансформаторов и ряда электрических машин. Поскольку такие материалы могут работать на частотах от 1 кГц и выше, это позволит существенно снизить габаритные размеры и повысить эффективность электротехнических изделий
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