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101.
102.
A new approach to analysis of the synchronization of chaotic oscillations in two (or more) coupled oscillators is described that makes it possible to reveal changes in the structure of attractors and detect the appearance of intermittency. The proposed method is based on a symbolic analysis developed previously in the velocity-curvature space of multidimensional sequences and maps. The method is tested by application to a Lorentz system. The results confirm the informativity of the analyzer and reveal specific features of changes in the structure of an attractor of the three-component test system.  相似文献   
103.
ABSTRACT

The review summarizes diverse knowledge about the problem of Linum usitatissimum L. response on photoperiod. Within this species, high genetic variability of the photosensitivity degree and influence of photoperiod on different plants characters were discovered. It was shown that in flax, earliness of flowering in long daylight is not strictly related to the low photosensitivity, and late genotypes with low photosensitivity can be found. In short daylight, various plant characters of different genotypes can be stable or display different reactions: increase or decrease their values. Also, the degree of photosensitivity does not have stable correlations with agronomic characters.  相似文献   
104.
Winter wheat is the most important cereal in Uzbekistan. Although the processing industry recognizes the low quality of local wheat, the present land use policy prioritizes production quantity, and wheat of better quality is imported to improve local flour. Yet, with increasing world market prices, Uzbekistan has to decide whether to continue allocating considerable resources for imports or to start investing in local quality improvements. This study therefore analyzed wheat production in the Khorezm region of Uzbekistan by (a) assessing the economic feasibility of local production vs. imports; and by (b) evaluating the current N-fertilizer management at field level in order to identify options for improving quality. Demand for wheat in the region currently falls short of supply by 79,000 t but under favorable world market prices, funds for importing additional wheat could be covered by cotton sales. Prices above $148 USD t−1 support the present land use policy to cultivate wheat but the baking quality of the crop is low. Higher N rates and/or an additional application of N at anthesis significantly increased grain quality. Additional costs for changes in N management, however, are currently not compensated by the price premiums at the State mills. Thus, in the absence of price incentives, it is unrealistic to expect producers to maximize quality production. Consequently, administrators must give quality greater attention by creating incentives through price differentials for higher quality, and encouraging awareness programs on wheat quality and improved on-field N management.  相似文献   
105.
Abstract

The biodegradation of the fullerene molecule C60 under the action of the human myeloperoxidase enzyme accompanied by a complete loss of the topology of the fullerene core. Analysis of this reaction mixture using UV and FTIR spectroscopy, chromatographic and mass spectrometry methods showed that the degradation proceeds without the formation of significant amounts of hydroxylated compounds. Among other intermediate compounds aromatic compounds were detected.  相似文献   
106.
We have successfully fabricated polycrystalline diamond rectifying junction devices on n-type (1 0 0) silicon substrates by Hot Filament Chemical Vapor Deposition (HFCVD) using methane/hydrogen process gas and trimethyl borate and trimethyl phosphite dissolved in acetone as p- and n-type dopants, respectively. Impedance spectroscopy and current-voltage analysis indicates that the conduction is vertical down the grains and facets and not due to surface effects. Electrical characteristics were analyzed with In and Ti/Au top metal contacts with Al as the substrate contact. Current-voltage characteristics as a function of temperature showed barrier potentials of 1.1 eV and 0.77 eV for the In and Ti/Au contacts, respectively. Barrier heights of 4.8 eV (In) and 4.4 eV (Ti/Au) were obtained from capacitance-voltage measurements.  相似文献   
107.
The feasibility of creating high-current leads on the basis of second-generation (2G) high-temperature superconductors (HTSs) was demonstrated. A method for graded soldering of 2G HTS tape stacks is proposed. It allows one to avoid negative effects that are related to an inhomogeneous current sharing between parallel HTS conductors. A prototype of HTS-coated current leads (CLs) was designed, manufactured, and tested; its critical current exceeds 18 kА. Prototypes of HTS CLs for the superconducting magnetic system of the Nuclotron accelerator (a part of the NICA collider) with an operating current of 6 kA were developed, manufactured, and tested in liquid helium (the overcurrent was 9 kA).  相似文献   
108.
Lukyanova  L. N.  Makarenko  I. V.  Usov  O. A. 《Semiconductors》2022,56(3):195-200
Semiconductors - The morphology of the (0001) interlayer surface has been investigated by scanning tunneling microscopy in n-Bi1.6Sb0.4Te2.94Se0.06, n-Bi1.8Sb0.2Te2.82Se0.09S0.09,...  相似文献   
109.
The objective of this work was the fractionation of beeswax to investigate the phase behavior of binary blends of the fractions and their potential use as gelling agents in edible oleogels. We have extracted seven distinctive fractions, using preparative flash chromatography with eluents permitted to be used in the processing of food raw materials. The odor profile of the fractions was characterized. The high purity of collected fractions was shown through thin-layer chromatography, Fourier-transform infrared spectroscopy, and high-performance liquid chromatography with an evaporative light scattering detector methods for hydrocarbons (94.8%), monoesters (97.6%), and mixed mono-, di-, and triesters fraction (98.7%). Free fatty acids and fatty alcohol fractions had lower purity which equals 82.6% and 39%, respectively. The analysis of the binary pseudo phase diagram revealed that all fractions combined with hydrocarbons express eutectic behavior. Combinations of all other fractions resulted in the formation of solid solutions. This study shows that the texture of oleogels can be improved by using a combination of various fractions of beeswax instead of native wax.  相似文献   
110.
Lanthanum zirconate has been prepared via a new chemical synthesis method by combining sol–gel processing and complex precipitation. The synthesis was carried out in aqueous solution under ambient conditions. The synthesized powder possessed the pyrochlore superstructure upon calcination above 1200°C. A suite of characterization techniques, including FTIR, Raman, X‐ray and electron diffraction, TEM, SEM, and nitrogen sorption were employed to investigate the microstructural evolution and bulk properties. Dense ceramics (>90% relative density) were obtained after sintering at 1400°C, without need for additional processing (i.e., hot or cold isostatic pressing) or any milling steps. A mechanism has been proposed that elucidates molecular assembly of this chemical synthesis method.  相似文献   
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