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51.
The results of experimental studies of elastoplastic deformation in structural materials of different grades in a complex state of stress at low temperatures are analyzed. It is shown that the degree of the effect of temperature and force conditions on the character of materials’ strain hardening at low temperature depends on their nature and structural state. The principal hypotheses and postulates that form the basis of the modern plasticity theories are examined for low temperatures. Two new models are introduced to describe the elastoplastic deformation of quasi-brittle and metastable materials under the simple loading with consideration for the effect of low temperatures on their structural state and mechanical properties. 相似文献
52.
Zinchenko AA Tanahashi M Murata S 《Chembiochem : a European journal of chemical biology》2012,13(1):105-111
A group of azobenzene derivatives containing two quaternary ammonium groups with various intercharge distances between them was synthesised and used to control photochemically the conformation of genomic DNA by switching the distance between cationic ammonium groups in the dications. It was found that isomerisation of either dication from the trans form to cis resulted in an increase in the dication's efficiency for DNA compaction; this is associated with a decrease in intercharge distance between ammonium groups and leads to a better match of the binder's cationic groups to adjacent phosphate groups of DNA. Ammonium dications have several important advantages over the photosensitive surfactant type of diazobenzene reported earlier: they can be used at significantly lower (>100-fold) concentrations than photosensitive surfactants, and DNA conformation control can be performed over a broader concentration range of dications. The influence of intercharge distance in photosensitive dications on photo-induced DNA binding discrimination is discussed, and the molecular mechanism is proposed. 相似文献
53.
This paper discusses a type of redundancy that is typical in a multi-state system. It considers two interconnected multi-state systems where one multi-state system can satisfy its own stochastic demand and also can provide abundant resource (performance) to another system in order to improve the assisted system reliability. Traditional methods are usually not effective enough for reliability analysis for such multi-state systems because of the “dimensional curse” problem. This paper presents a new method for reliability evaluation for the repairable multi-state system considering such kind of redundancy. The proposed method is based on the combination of the universal generating function technique and random processes methods. The numerical example is presented to illustrate the proposed method. 相似文献
54.
Evgeniya V. Pushchina Maria E. Bykova Ekaterina V. Shamshurina Anatoly A. Varaksin 《International journal of molecular sciences》2022,23(9)
Corpus cerebelli in juvenile chum salmon is a multiprojective region of the brain connected via afferent and efferent projections with the higher regions of the brainstem and synencephalon, as well as with multiprojection regions of the medulla oblongata and spinal cord. During the postembryonic development of the cerebellum in chum salmon, Oncorhynchus keta, the lateral part of the juvenile cerebellum gives rise to the caudomedial part of the definitive cerebellum, which is consistent with the data reported for zebrafish and mouse cerebellum. Thus, the topographic organization of the cerebellum and its efferents are similar between fish (chum salmon and zebrafish) and mammals, including mice and humans. The distributions of recombinant adeno-associated viral vectors (rAAVs) after an injection of the base vector into the cerebellum have shown highly specific patterns of transgene expression in bipolar neurons in the latero-caudal lobe of the juvenile chum tectum opticum. The distribution of rAAVs in the dorsal thalamus, epithalamus, nucleus rotundus, and pretectal complex indicates the targeted distribution of the transgene via the thalamo-cerebellar projections. The detection of GFP expression in the cells of the epiphysis and posterior tubercle of juvenile chum salmon is associated with the transgene’s distribution and with the cerebrospinal fluid flow, the brain ventricles and its outer surface. The direct delivery of the rAAV into the central nervous system by intracerebroventricular administration allows it to spread widely in the brain. Thus, the presence of special projection areas in the juvenile chum salmon cerebellum, as well as outside it, and the identification of the transgene’s expression in them confirm the potential ability of rAAVs to distribute in both intracerebellar and afferent and efferent extracerebellar projections of the cerebellum. 相似文献
55.
Giorgio Dall'Olmo Anatoly A. Gitelson Donald C. Rundquist Bryan Leavitt John C. Holz 《Remote sensing of environment》2005,96(2):176-187
Bio-optical algorithms for remote estimation of chlorophyll-a concentration (Chl) in case-1 waters exploit the upwelling radiation in the blue and green spectral regions. In turbid productive waters other constituents, that vary independently of Chl, absorb and scatter light in these spectral regions. As a consequence, the accurate estimation of Chl in turbid productive waters has so far not been feasible from satellite sensors. The main purpose of this study was to evaluate the extent to which near-infrared (NIR) to red reflectance ratios could be applied to the Sea Wide Field-of-View Sensor (SeaWiFS) and the Moderate Imaging Spectrometer (MODIS) to estimate Chl in productive turbid waters. To achieve this objective, remote-sensing reflectance spectra and relevant water constituents were collected in 251 stations over lakes and reservoirs with a wide variability in optical parameters (i.e. 4 ≤ Chl ≤ 240 mg m− 3; 18 ≤ Secchi disk depth ≤ 308 cm). SeaWiFS and MODIS NIR and red reflectances were simulated by using the in-situ hyperspectral data. The proposed algorithms predicted Chl with a relative random uncertainty of approximately 28% (average bias between − 1% and − 4%). The effects of reflectance uncertainties on the predicted Chl were also analyzed. It was found that, for realistic ranges of Rrs uncertainties, Chl could be estimated with a precision better than 40% and an accuracy better than ± 35%. These findings imply that, provided that an atmospheric correction scheme specific for the red-NIR spectral region is available, the extensive database of SeaWiFS and MODIS images could be used to quantitatively monitor Chl in turbid productive waters. 相似文献
56.
Effect of bio-optical parameter variability on the remote estimation of chlorophyll-a concentration in turbid productive waters: experimental results 总被引:12,自引:0,他引:12
The analytical development and underlying hypothesis of a three-band algorithm for estimating chlorophyll-a concentration ([Chla]) in turbid productive waters are presented. The sensitivity of the algorithm to the spectral location of the bands used is analyzed. A large set of experimental observations ([Chla] varied between 4 and 217 mg m(-3) and turbidity between 2 and 78 nephelometric turbidity units) was used to calibrate and validate the algorithm. It was found that the variability of the chlorophyll-a fluorescence quantum yield and of the chlorophyll-a specific absorption coefficient can reduce considerably the accuracy of remote predictions of [Chla]. Instead of parameterizing these interferences, their effects were minimized by tuning the spectral regions used in the algorithm. This allowed us to predict [Chla] with a relative root-mean-square error of less than 30%. 相似文献
57.
58.
Anatolii S. Burlov Valery G. Vlasenko Maxim S. Milutka Yurii V. Koshchienko Nadezhda I. Makarova Vladimir A. Lazarenko Alexander L. Trigub Alexandra A. Kolodina Alexander A. Zubenko Anatoly V. Metelitsa Dmitrii A. Garnovskii Alexey N. Gusev Wolfgang Linert 《International journal of molecular sciences》2022,23(23)
New azomethine compounds of 2-(N-tosylamino)benzaldehyde or 5-chloro-2-(N-tosylamino)benzaldehyde and the corresponding chlorine-substituted anilines, zinc(II) complexes based on them have been synthesized. The structures of azomethines and their complexes were determined by elemental analysis, IR, 1H NMR, X-ray spectroscopy, and X-ray diffraction. It is found that all ZnL2 complexes have a tetrahedral structure according to XAFS and X-ray diffraction data. The photoluminescent properties of azomethines and zinc complexes in methylene chloride solution and in solid form have been studied. It is shown that the photoluminescence quantum yields of solid samples of the complexes are an order of magnitude higher compared to the solutions and range from 11.34% to 48.3%. The thermal properties of Zn(II) complexes were determined by thermal gravimetric analysis (TGA) and differential scanning calorimetry. The TGA curves of all the compounds suggest their high thermal stability up to temperatures higher than 290 °C. The electrochemical properties of all complexes were investigated by the cyclic voltammetry method. The multilayered devices ITO/PEDOT:PSS/NPD/Zn complex/ TPBI/LiF/Al with wide electroluminescence (EL) color range spanning the range from bluish-green (494 nm) to green (533 nm) and the high values of brightness, current and power efficiency were fabricated. The biological activity of azomethines and zinc complexes has been studied. In the case of complexes, the protistocidal activity of the zinc complex with azomethine of 5-chloro-2-(N-tosylamino)benzaldehyde with 4-chloroaniline was two times higher than the activity of the reference drug toltrazuril. 相似文献
59.
Oleg V. Surov Marina I. Voronova Natalia V. Rubleva Andrei V. Afineevskii Anatoly G. Zakharov 《应用聚合物科学杂志》2020,137(19):48662
Cellulose nanocrystals (CNCs) have been studied as compatibilizers for improving the interfacial miscibility of polymer binary blends. Binary blends of water-soluble polymers–poly(vinyl alcohol), poly(ethylene oxide), and polyvinylpyrrolidone—containing different amounts of CNC (16 and 25 wt %) were prepared by a solution casting method. For the first time, a systematic side-by-side comparison between the morphological, thermal, and mechanical properties of the polymer blends reinforced by CNC has been conducted. It has been determined that in the presence of CNC, the degree of crystallinity of the blend components decreased and the miscibility of the blends increased. The blends possess enhanced thermal and mechanical properties as a result of improved miscibility of the blend components. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2019 , 137, 48662. 相似文献
60.
Alexander A. Khassin Anatoly G. Sipatrov Galina K. Chermashetseva Tamara M. Yurieva Valentin N. Parmon 《Topics in Catalysis》2005,32(1-2):39-46
The Fischer–Tropsch synthesis using a contactor membrane reactor was studied varying pore size distribution parameters and membrane geometry. These parameters are responsible for the magnitude of the diffusion constrains and, therefore, correlate with the FTS process productivity and selectivity. The nature of the observed correlations is discussed. 相似文献