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51.
The possibility of experimental measurement of the Poynting vector characteristics is shown. Under paraxial approximation, these characteristics may be obtained on the basis of local Stokes polarimetry and interferometry of electric field components. The experimental results for elliptically polarized Gaussian beam and heterogeneously polarized elementary fields are presented.  相似文献   
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53.
The problem on collinear collision of two thermoelastic rods possessing the same rheological parameters but of different length and temperature is considered, in so doing before the impact the rods move unidirectionally along a common longitudinal axis with distinct constant velocities. Lateral surfaces and free ends of both rods are heat insulated, and free heat exchange between the rods occurs within contacting ends. The rods' thermoelastic behavior is described by the Green–Naghdy theory. Two methods are used as the methods of solution, namely: D'Alembert's method and the ray method. D'Alembert's method is based on the analytical solution of equations of the hyperbolic type describing the dynamic behavior of the thermoelastic rods. This solution involves four arbitrary functions which are determined from the initial and boundary conditions and are piecewise constant functions. The ray method is based on the theory of discontinuities and also allows one to obtain the solution involving four arbitrary constants. Both solutions complement each other, since D'Alembert's solution enables one to analyze the influence of thermoelastic parameters on the values to be found, while the solution via the ray method is best suited for numerical investigation of the longitudinal coordinate dependence of the desired values at each fixed instant of the time beginning from the moment of rods' collision up to the moment of their rebound. To illustrate the both approaches, the problem of the rods' collision without account for the stress and temperature fields coupling is also considered.  相似文献   
54.
This paper addresses the design and implementation of digital unbiased finite impulse response (FIR) filters with polynomial impulse response functions. The transfer function, its fundamental properties, and a general block-diagram are discussed for the impulse response represented with the l-degree Taylor series expansion. As a particular results, we show a fundamental identity uniquely featured to such filters in the transform domain. For low-degree impulse responses, the transfer functions are found in simple closed forms and represented in compact block-diagrams. The magnitude and phase responses are also analyzed along with the group delays. A comparison with predictive FIR filters is given. As examples of applications, filtering of time errors of local clocks is discussed along with the low-pass filter design employing a cascade of the unbiased FIR filters.  相似文献   
55.
The light‐induced reversible switching of the swelling of microgel particles triggered by photo‐isomerization and binding/unbinding of a photosensitive azobenzene‐containing surfactant is reported. The interactions between the microgel (N‐isopropylacrylamide, co‐monomer: allyl acetic acid, crosslinker: N,N′‐methylenebisacrylamide) and the surfactant are studied by UV‐Vis spectroscopy, dynamic and electrophoretic light scattering measurements. Addition of the surfactant above a critical concentration leads to contraction/collapse of the microgel. UV light irradiation results in transcis isomerization of the azobenzene unit incorporated into the surfactant tail and causes an unbinding of the more hydrophilic cis isomer from the microgel and its reversible swelling. The reversible contraction can be realized by blue light irradiation that transfers the surfactant back to the more hydrophobic trans conformation, in which it binds to the microgel. The phase diagram of the surfactant‐microgel interaction and transitions (aggregation, contraction, and precipitation) is constructed and allows prediction of changes in the system when the concentration of one or both components is varied. Remote and reversible switching between different states can be realized by either UV or visible light irradiation.  相似文献   
56.
This paper presents and discusses an extension of the pseudotransient continuation-based steady state solver for hydraulic networks proposed previously to the case of zero flow rates. The original solver, which reduces the solution of the governing nonlinear algebraic equations to the numerical integration of an initial-value problem, has problems in situations in which the head derivative of the flow rate tends to infinity, as is the case with zero flow rates. The extension is on the basis of the use of a model headloss-flow relationship that coincides with the true one at zero and has a finite head derivative at that point. This modified steady state solver is free from some convergence problems that occur in Newton-Raphson method-based solvers when analyzing a pipe network with control devices. The paper includes the results of the numerical analysis of test networks, which demonstrate the convergence of the modified steady state solver for cases in which existing steady state solvers have troubles.  相似文献   
57.
The purpose of given article-consideration of the basic features of modern manufacturing of nuclear fuel which would confirm fact, that the manufacturer does everything that its production would respond not only to requirements of the consumer, but also to its expected inquiries, and would correspond to intended purposes of fuel. It was defined main tendencies and features of modern technology, especially in nuclear fuel production, on base of meeting discussions, themes of journal articles on nuclear subject. They are correspond with practice of JSC NCCP (Novosibirsk Chemical Concentrates Plant) and listed in the paper. In result of it number of base features of any advanced technology, not only nuclear, described here with examples from NCCP's practice. Of course, there is no certain list of all attributes of modern manufacturing as there is no limit to its perfection. These categories are forming by current needs of the market, but listed ones must be.  相似文献   
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59.
The first results of manufacturing and investigations of a new type of nanocomposite protective coatings are presented. They were manufactured using a combination of two technologies: plasma-detonation coating deposition with the help of plasma jets and thin coating vacuum-arc deposition. We investigated structure, morphology, physical and mechanical properties of the coatings of 80–90 μm thickness, as well as defined the hardness, elastic Young modulus and their corrosion resistance in different media. Grain dimensions of the nanocomposite coatings on Ti–N–Cr base varied from 2.8 to 4 nm. The following phases and compounds formed as a result of plasma interaction with the thick coating surface were found in the coatings: Ti–N–Cr (200), (220), γ-Ni3–Fe, a hexagonal Cr2–Ti, Fe3–Ni, (Fe, Ni)N and the following Ti–Ni compounds: Ti2Ni, Ni3Ti, Ni4Ti, etc. We also found that the nanocomposite coating microhardness increased to H = 31.6 ± 1.1 GPa. The Young elastic modulus was determined to be E = 319 ± 27 GPa – it was derived from the loading–unloading curves. The protective coating demonstrated the increased corrosion resistance in acidic and alkaline media in comparison with that of the stainless steel substrate.  相似文献   
60.
Pain is a common symptom that impairs the quality of life for people around the world. Local anesthetics widely used for pain relief have a number of side effects, which makes the development of both new drugs and new ways to control their activity particularly important. Photopharmacology makes it possible to reduce the side effects of an anesthetic and control its biological activity in the body. The purpose of this work was to create a new light-controlled local anesthetic and study its biological activity in animals. A compound with a simple scheme of synthesis was chosen to shift the UV-Vis absorption band towards the visible range of the spectrum and was synthesized for the first time. Some computer calculations were performed to make sure that the aforementioned changes would not lead to loss of biological activity. The micellar form of the new compound was prepared, and in vivo biological studies were carried out in rabbits. The existence of a local anesthetic effect, which disappeared almost completely on irradiation with light (λ = 395 nm), was shown using the surface anesthesia model. Moreover, the possibility of multiple reversible changes in the biological activity of ethercaine under the action of light was demonstrated. The latter compound manifests no local irritating effect, either. The data obtained indicate the prospects for the development of new compounds based on azobenzene for light-controlled local anesthesia.  相似文献   
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