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61.
62.
Aleksandr I Nikiforov Vyacheslav A Timofeev Serge A Teys Anton K Gutakovsky Oleg P Pchelyakov 《Nanoscale research letters》2012,7(1):561
Critical thicknesses of two-dimensional to three-dimensional growth in GexSi1−x layers were measured as a function of composition for different growth temperatures. In addition to the (2 × 1) superstructure for a Ge film grown on Si(100), the GexSi1−x layers are characterized by the formation of (2 × n) reconstruction. We measured n for all layers of Ge/GexSi1−x/Ge heterosystem using our software with respect to the video recording of reflection high-energy electron diffraction (RHEED) pattern during growth. The n reaches a minimum value of about 8 for clear Ge layer, whereas for GexSi1−x films, n is increased from 8 to 14. The presence of a thin strained film of the GexSi1−x caused not only the changes in critical thicknesses of the transitions, but also affected the properties of the germanium nanocluster array for the top Ge layer. Based on the RHEED data, the hut-like island form, which has not been previously observed by us between the hut and dome islands, has been detected. Data on the growth of Ge/GexSi1−x/Ge heterostructures with the uniform array of islands in the second layer of the Ge film have been received. 相似文献
63.
Results on experimental investigation of heat transfer in the liquid films dichlorofluoromethane R21 and dichlorotetrafluoroethane R114 Freon mixture over the vertical tubes are presented. We have studied the film flow over the outer surface of tubes with 50-mm diameter and different configurations: smooth surface, horizontal ribs, and diamond-shape knurling. Heat transfer coefficients were measured under the conditions of evaporation and nucleate boiling together with wave characteristics of the falling film, binary mixture composition, and critical heat fluxes corresponding to dry spots formation. The film Reynolds number at the inlet to the test section was varied from 15 to 250. At evaporation regime the heat transfer coefficient for a smooth surface decreases classically with an increase of Reynolds number. Dependence of heat transfer coefficient on irrigation density for the surface with diamond-shape knurling is similar to dependence for the smooth surface with insignificant heat transfer intensification. The heat transfer coefficients at nucleate boiling for the studied structured surfaces are close to those obtained for the smooth tube. Development of critical phenomena is determined by regularities of dry spots formation typical for evaporation of the wavy liquid film. 相似文献
64.
65.
A method is considered for ensuring failure-resistant operation of computer memory devices which is based on linear correcting
codes with a posteriori correction of multiple errors. The proposed method makes it possible to extend the correcting possibilities
of the code, i.e., to determine the configuration of any error with minimum code redundancy, requirements of hardware and
time.
Translated from Izmeritel'naya Tekhnika, No. 4, pp. 21–28, April. 2000. 相似文献
66.
Vladimir Tereshin Aleksandr Bovda Vera Bovda Oleg Byrka Vladimir Chebotarev Vladimir Fedorchenko Igor Garkusha 《Vacuum》2006,80(11-12):1272
The results of film deposition of pure tungsten as well as intermetallic compound of NdFeB type on various substrates using planar ECR plasma source (with multipole magnetic field) developed in our laboratory are presented. The frequency of 2.45 GHz was generated within the magnetic system by two-slot antenna. The ions of ECR argon plasma are used for target sputtering. The main plasma parameters are density 1010 cm−3, Te15 eV, ions energy 20 eV, ion current density 3.5 mA/cm2 at the ultimate magnetron power. Under sputtering of Nd8Fe86B6 target the amorphous films with high adherence and thickness of 5 μm were formed on the substrate. The deposition rate of tungsten films (target biasing 900 V) was 0.59 nm/s. The fine-grained films with high adhesion were obtained. They were tested against heat loads up to 100 J/cm2 produced under irradiation of coatings with plasma streams. 相似文献
67.
68.
V. A. Timiryazev A. S. Kalashnikov V. A. Kuznetsov A. V. Smirnov S. Yu. Yurasov Yu. V. Maksimov O. I. Yurasova E. A. Ryabov N. S. Krinitsyn 《Russian Engineering Research》2020,40(1):64-66
We consider computer software for automated calculation of the dimensional relations of machines in terms of the rated values and tolerances, in the light of the selected method for ensuring precision. 相似文献
69.
Utilization of Extrinsic Fabry-Perot Interferometers with Spectral Interferometric Interrogation for Microdisplacement Measurement 下载免费PDF全文
The paper presents a number of signal processing approaches for the spectral interferometric interrogation of extrinsic Fabry-Perot interferometers (EFPIs). The analysis of attainable microdisplacement resolution is performed and the analytical equations describing the dependence of resolution on parameters of the interrogation setup are derived. The efficiency of the proposed signal processing approaches and the validity of analytical derivations are supported by experiments. The proposed approaches allow the interrogation of up to four multiplexed sensors with attained resolution between 30 pm and 80 pm, up to three times improvement of microdisplacement resolution of a single sensor by means of using the reference interferometer and noise-compensating approach, and ability to register signals with frequencies up to 1 kHz in the case of 1 Hz spectrum acquisition rate. The proposed approaches can be used for various applications, including biomedical, industrial inspection, and others, amongst the microdisplacement measurement. 相似文献
70.
Pu Chun Ke Emily H. Pilkington Yunxiang Sun Ibrahim Javed Aleksandr Kakinen Guotao Peng Feng Ding Thomas P. Davis 《Advanced materials (Deerfield Beach, Fla.)》2020,32(18):1901690
Amyloidosis is a biophysical phenomenon of protein aggregation with biological and pathogenic implications. Among the various strategies developed to date, nanomaterials and multifunctional nanocomposites possessing certain structural and physicochemical traits are promising candidates for mitigating amyloidosis in vitro and in vivo. The mechanisms underpinning protein aggregation and toxicity are introduced, and opportunities in materials science to drive this interdisciplinary field forward are highlighted. Advancement of this emerging frontier hinges on exploitation of protein self-assembly and interactions of amyloid proteins with nanoparticles, intracellular and extracellular proteins, chaperones, membranes, organelles, and biometals. 相似文献