Application experience of gas-thermal aluminum coatings to protect the pipes for underground construction and repair of heat networks

Questions of sacrificial protection for pipes of underground heat networks with aluminum against the external corrosion are considered. The description of pilot production of pipes with a plasma aluminum coating and the deposition of a sacrificial gas-plasma aluminum coating on weld joints of pipelines and the zone of their thermal influence during assemblage is presented. Examples of repairing the segments of distribution heat networks by the pipes with the tread protection are presented. © 2013 Pleiades Publishing, Inc

Many cusped hyperbolic 3-manifolds do not bound geometrically

In this note we show that there exist cusped hyperbolic 3-mani-folds that embed geodesically but cannot bound geometrically. Thus, being a geometric boundary is a non-trivial property for such manifolds. Our result complements the work by Long and Reid on geometric boundaries of compact hyperbolic 4-manifolds and by Kolpakov, Reid, and Slavich on embedding arithmetic hyperbolic manifolds

Rogue waves driven by polarization instabilities in a long ring fiber oscillator

We present an experimental and theoretical results of a study of a complex nonlinear polarization dynamics in a passively self-mode-locked erbium-doped fiber oscillator implemented in a ring configuration and operating near lasing threshold. The theoretical model consists of seven coupled non-linear equations and takes into account both orthogonal states of polarizations in the fiber. The experiment confirmed the existence of seven eigenfrequencies, predicted by the model due to polarization instability near lasing threshold. By adjusting the state of polarization of the pump and in-cavity birefringence we changed some eigenfrequencies from being different (non-degenerate state) to matching (degenerate state). The non-degenerate states of oscillator lead to the L-shaped probability distribution function and true rogue wave regime with a positive dominant Lyapunov exponent value between 1.4 and 2.6. Small detuning from partially degenerate case also leads to L-shaped probability distribution function with the tail trespassing eight standard deviations threshold, giving periodic patterns of pulses along with positive dominant Lyapunov exponent of a filtered signal between 0.6 and 3.2. The partial degeneration, in turn, guides to quasi-symmetric distribution and the value of dominant Lyapunov exponent of 42 which is a typical value for systems with a source of the strongly nonhomogeneous external noise

The local crystallization in nanoscale diamond-like carbon films during annealing

The local crystallization during annealing at 600° C in nanoscale diamond-like carbon coatings films grown by pulsed vacuum-arc deposition method was observed using modern techniques of high-resolution transmission electron microscopy. The crystallites formed by annealing have a face-centred cubic crystal structure and grow in the direction [011] as a normal to the film surface. The number and size of the crystallites depend on the initial values of the intrinsic stresses before annealing, which in turn depend on the conditions of film growth. The sizes of crystallites are 10 nm for films with initial compressive stresses of 3 GPa and 17 nm for films with initial compres- sive stresses of 12 GPa. Areas of local crystallization arising during annealing have a structure dif- ferent from the graphit

The use of degassing hydrocyclone to intensify integrated training for water heat networks

Работа посвящена современным способам интенсификации процесса деаэрации и снижения затрат за счет многоступенчатого процесса, включающего предварительную дегазацию воды в закрученном потоке. Автор рассматривает теоретические основы центробежно-вихревого метода деаэрации, раскрывает особенности комбинированного использования вихревой и термической деаэрации, а также приводит и обрабатывает результаты опытно-промышленных исследований деаэрационных установок.The work is devoted to modern methods intensification of de-aeration and reduce the cost of the process due to the multi-stage process comprising pre-degassed water into a swirling stream. The author examines the theoretical basis of centrifugal vortex method of de-aeration, reveals features the combined use of a vortex and thermal de-aeration, as well as results and processes the results of pilot studies de-aeration plants

Simulation of coolant mixing in the vortex device

Настоящая работа посвящена исследованию процесса взаимодействия потоков теплоносителей при смешении в циклонно-вихревых агрегатах, в частности в вихревом смесителе, с целью применения результатов моделирования для проектирования вихревых конденсаторов.The present work is devoted to research of process of interaction of streams of coolant when mixed in a cyclone-vortex assemblies, in particular in a vortex mixer, with the aim of applying the results of simulation for the design of vortex capacitors

Experiments on rehabilitation of radioactive metallic waste (RMW) of reactor stainless steels of Siberian chemical plant

Stainless steel pipes, used to cool a reactor plant, have a high cost, and aftertaking a reactor out of service they must be buried together with other radioactivewaste. Therefore, the relevant problem is the rinse of pipes from contamination,followed by returning to operation

Nanostructured coatings based on amorphous carbon and gold nanoparticles obtained by the pulsed vacuum-arc method

Nanostructured coatings based on diamond-like carbon and gold-doped carbon with a thickness of 100-300 nm were obtained by a pulsed vacuum-arc method on silicon substrates. The structure of the coatingswas studied by high-resolution transmission electron microscopy, the elemental composition was studied by X-ray microanalysi

Changes in normalized permutation entropy during non-coherent pulsepulse interaction in the laser cavity

Summary form only given. Statistically extreme events, that is to say, the events which have L-shaped probability distribution function (PDF, or in other words L-statistics) and, in particular, the rogue wave (RW) events, constitute a special family of natural phenomena. Curiously, this kind of events is more common than it is believed. It was observed that the behavior of the systems which obey L-shaped statistics is clustered. Periods of high predictability and low volatility are followed by periods of drastic changes and high volatility, for example, RWs [1], earthquakes, epileptic seizures etc. Permutation entropy (PE) is an indicator of dynamical predictability of the system [2, 3] which allows quantization of the predictability or volatility. We report an investigation of using it to characterize the uncertainty period which was observed during pulse-pulse interaction in a long ring laser resonator without a saturable absorber. These resonators, in particular, the resonator built using Er3+ doped fiber (Fig.1), have polarization dependent instability near the lasing threshold [4] which leads to the generation of pulses propagating with different speed, either randomly or regularly. Using this property, an investigator can observe the mechanism of the pulse-pulse interaction in detai

Experiments on rehabilitation of radioactive metallic waste (RMW) of reactor stainless steels of Siberian chemical plant

Stainless steel pipes, used to cool a reactor plant, have a high cost, and aftertaking a reactor out of service they must be buried together with other radioactivewaste. Therefore, the relevant problem is the rinse of pipes from contamination,followed by returning to operation