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Рассматривается вопрос силового взаимодействия элементов стальных канатов (проволока, пряди и др.) при работе на блоках. Первоначально исследуется вопрос взаимного относительного перемещения проволоки при изгибе. Это явление более широко известно как депланация поперечного сечения проволочного каната. При определении дополнительных смещений учтено, что удлинение элементов каната происходит в обе стороны от точки набегания каната на блок (и в прямолинейный, и в криволинейный участки каната). Также учитываются дополнительные смещения, возникающие в изогнутой части каната.Решается задача аналитического определения сил трения между проволоками каната, набегающего на вращающийся блок. Используемый подход основан на решении уравнения Эйлера для изогнутой на барабане нити. На завершающем этапе установлены зависимости для работы сил трения в зависимости от коэффициента трения между контактирующими поверхностями, обусловленные видом канатной смазки. В частности из полученных выражений следует, что при уменьшении коэффициента трения между элементами каната произойдет снижение совершаемой силами трения работы. Полученные результаты подтверждают, что использование эффективной канатной смазки будет способствовать энергосбережению, продлению срока службы стального каната.

The paper applies machine learning methods to the prediction of the abrasive weight wear rates for a set of wear resistance experiments with model samples made of electrical copper and pure aluminum. To assess the effect of rotation frequency and abrasive grit sizes on the results of the evaluation of wear resistance and the determining quantities, the samples are tested with various disc rotation frequencies and various sandpaper grit sizes. It is noteworthy that, during experiments with materials comparable to copper in hardness and with harder ones, the path specified by the test design is implemented completely. However, this test design is not always suitable for the analysis of the mechanical characteristics of aluminum since, in some cases, the sample becomes fully worn before the end of the test. To overcome this problem, machine learning (ML) methods are proposed.

It is established that the heteroadagulation of microdroplets of chlorobenzene or microdroplets of water brine on carbon tissue in the vicinity of the inversion point occurs in the kinetic mode or close to it. It is noted that the presence of the kinetic mode explains the linearity of kinetic curves along at least two-thords of their length. The sudden disappearance of microdroplets from the field of view upon a slight increase in grinding frequency is explained by the microdroplets achieving critical wavelength. It is concluded that at low concentrations of microdroplets, heteroadagulation curves acquire S-shaped form in any phase, due to the relative importance of interdroplet interactions in the subsurface layers. The abrupt transition of ascending kinetic lines and their transformation into horizontal lines indicates there are no more visible droplets; i.e., drops cannot be observed optically.

The statistical parameters of hydrodynamic heteroadagulation of microdrops of solar oil with sizes of 0.5–2 μm have been obtained for the first time. The problem is of a great practical significance because the agglomeration of microdrops leads to substantial acceleration of purification of aqueous phase from them according to hydrodynamic heteroadagulation (HHA). HHA has been studied in the broad range of the rotation frequencies of rotor discs from 200 to 2000 min−1. Root-mean-square deviations S have been calculated in all points of kinetic curves and also their relative errors δ% have been obtained. The methods of analyzing the u-distributions and Student t-distributions have been used. The trends of random deviations of kinetic curves of heteroadagulation from mean values have been determined.

We have examined the requirements of valve assemblies used in gas distribution networks, reviewed the materials used for making packing surfaces of ball cocks, analyzed the basic causes of failures, conducted experimental studies, and determined the contribution of each wearing process (wearing due to friction of packing surfaces of shutoff unit, fretting, and attack of gas-abrasive stream) that causes failure of packing surfaces of valve assemblies. Based on the studies conducted on determination of wear resistance of materials and the analysis made of the contribution of each factor, we have built a mathematical model to determine the mean time between failures of valve assemblies for various operation conditions.

Nesting bird communities of individual habitat types in the Arkaim reserve are formed every year under the influence of nonrandom factors. Their qualitative and quantitative composition may gradually shift in a certain direction, but more often it remains relatively stable over several years and then makes an abrupt transition into a different state. The strongest effect on the dynamics of these communities has been exerted by progressive succession following the assignment of special protection status to the Arkaim area. The effects of fires and other elemental factors are also significant.

Рассматривается вопрос оценки долговечности стальных канатов, работающих на блоках с учетом контактного взаимодействия проволок. Описаны основные виды напряжений, возникающих при эксплуатации стальных канатов. Приведены сведения, необходимые для проведения испытаний стальных канатов на долговечность при изгибе. Для определения долговечности стальных канатов при работе на блоках используются эмпирические зависимости, учитывающие множество факторов: действующую нагрузку, отношение диаметров каната и блока, предел прочности материала проволок, диаметр каната, длину пробега каната по блоку, тип сердечника, форму канавки блока, тип и методику смазки стального каната и др. Показано, что при изгибе каната на блоке возникают относительные смещения элементов стального каната, приводящие к возникновению явления фреттинг-износа. Для возбуждения этого процесса достаточны перемещения поверхностей с амплитудой 0,025 мкм. Величина относительных микросмещений проволок в стальном канате зависит в первую очередь от отношения диаметра каната к диаметру блока и экспоненциально увеличивается при его уменьшении. Таким образом, малый диаметр блока является неблагоприятным фактором, и его критический размер может быть установлен, исходя из анализа полученных решений.

The development of personality strongly depends on correspondence of chosen profession to capacities and interests of specialist, labor market demand and possibility of career making. The particular dynamics is observed in alteration of conception of professions and professional activities because information revolution resulted in shifting from mono-professionalism to mastering of several professions at once. The profession of pharmacist also passed through several alterations following development of pharmaceutical industry. The results of survey of opinions of students of pharmaceutical faculties concerning choice of profession of pharmacist demonstrate an actual situation at industry market and give an opportunity of forecasting its development in Moscow for nearest years.

The process of the microdrop coarsening of KhA-30 compressor oil on carbon fabric is studied. The problem is connected with the necessity of the cleaning of air and water from the microdrops of oils cooling the compressors. The heteroadagulation method allowed for the separation of water from compressor oil particles with a diameter 0.8–7.6 μm over the course of a few minutes. The oiling of the carbon fabric is reduced to a minimum. For the first time, by an order of magnitude, finer discontinuities, which can behave as stable cluster origination centers, are observed on the surface of micron-sized oil drops.

We consider the hydrodynamic heteroadagulation method for water purification from microdrops of organic liquids with a size of 0.8–10 μm and concentration of 0.02–2.0%. A mathematical model of the process is proposed. The role of material for heteroadagulation, the rotation frequency of dispenser rotors and heteroadagulator mixer, and the pH level were discussed. Purification from microdrops is ascertained to be ∼93–99% fulfilled over 5–25 min. We reveal and interpret the reason for aliasing of kinetic curves of heterodynamic heteroadagulation and its appreciable acceleration or deceleration upon the introduction of a second set of drops larger than the first by a factor of 300–500.

The effect of the emulsifier formula on the stability of castor oil-water system was studied through compounding three groups of emulsifiers from the aspects of stability factor of absorbance, centrifuge stability, demulsification time in quiescence, appearance of the droplets, and viscosity. The best emulsifier formula for castor biomass oil was the composite formula of sorbitan monooleate and polyoxyethylene sorbitan monostearate. Correlation exists between the stability of emulsion and the viscosity/particle size of the droplets, with better stability in the case of greater viscosity or narrower distribution of particle size in the emulsion of castor oil-water system. Methanol added to the castor oil-water system may decrease the viscosity of the emulsion. Comparing the castor oil-water emulsion with methanol-castor oil-water emulsion, the optimal hydrophilic and lipophilic balance (HLB) value based on castor oil-water system was acquired between 6.6 and 7.5, while the optimal HLB value based on the methanol-castor oil-water system was between 5.5 and 6.0. The optimal HLB value of methanol-castor oil-water system gradually moved to that of castor oil-water emulsion with adding more water.

We report our observations on the resonance signals of masses of 1520, 1670, 1810 (1 820), and 2100 MeV c−2, produced inclusively in the reaction Σ− + C(Cu) → p + K− + X, and the signals of masses of 1020 and 1525 MeV c−2, produced inclusively in the reaction Σ− + C(Cu) → K+ + K− + X, with a 600-GeV c−1- momentum hyperon beam in the SELEX experiment at the Fermilab. The masses, widths, and branching ratios were measured. The resonance signal of mass of 1520 MeV c−2 correspond to the known Λ(1520) hyperon. The signals of masses of 1020 and 1525 MeV c−2 in the K+K− system correspond to the φ0(1020)- and f2′(1525) mesons, respectively. The branching ratio of the resonance of mass of 1670 MeV c−2 relative to Λ(1520) is (24.92 ± 0.45 ± 0.48)%, while that of the resonance of mass of 1810 (or 1 820) MeV c−2 relative to Λ(1520) is (16.13 ± 0.38 ± 0.45)%. The branching ratio of the f2′(1525) resonance relative to φ0(1020) is (10.75 ± 0.25 ± 0.45)%. Data analysis was performed over 6 × 107 trigger events registered by the SELEX setup on the FNAL Tevatron.

Effect of diluents on the coarsening of microdrops of tri-n-butyl phosphate by hydrodynamic heteroadagulation on a carbon fabric in water was studied.

Reaction kinetics of ozone destruction in water in the presence of an anion and a cation impurity has been examined. Cromates and, possibly, a complex anion of iron with a valence of three have the strongest catalytic property among all tested anions. Cations do not influence the reaction rate of ozone destruction.

The IR spectra in the hydroxyl group stretching vibration region of the simplest hydroxyalkylpyrrolizidines have been examined. The spectra were taken in the form of pure liquids, dilute solutions in carbon tetrachloride, and for individual bases in the gas phase. It was shown that in dilute solutions ΔνOH depends on the geometric parameters of the intramolecular hydrogen bond (IMHB). The energy of the IMHB of 3-(2-hydroxyethyl)pyrrolizidine was measured in dilute solution and in the gas phase.

A software framework for a physical analysis of the results of experiments at a hadron spectrometer has been developed. This software is used to analyze the data of the SELEX experiment.

Coalescence of KHA-30 compressor oil microdroplets on a carbon fabric, aimed to remove them from air and water streams used for compressor cooling, was examined.

The kinetics of the spreading of polymolecular films are studied. It is shown that they move slower than monomolecular films with the polar liquid Midel 7131 moving especially slowly. The cause of the considerably slower motion of surfactants is explained.

The linearization of kinetic curves of the decoloration of direct green and methylene blue dyes and humic acids is performed. It is shown that the kinetic curves can be linearized in the time-square root of the negative logarithm of reduced optical light absorption or ozone concentration coordinates. This provides a simple way of modeling and optimizing ozonation processes.

The problem of purifying water from microscopic oil drops without using reagent heating has been solved using the technique of a directed motion of drops, i.e., the method of heterogeneous hydrodynamic coagulation. The efficiency of water purification from microscopic oil drops, including those of the petroleum origin, is equal to 95–99% per one stage. The purification process lasts 10–30 min.

Ultra-fine zinc oxalate powders were prepared through a precipitation stripping method with bis(2-ethylhexyl) phosphate (HDEHP) diluted by tetrachloride carbon as the extractant, and oxalic acid ethanol aqueous solution as the re-extractant and precipitator. Zinc oxide powders were obtained by decomposing zinc oxalate powders at 450uC. The prepared zinc oxide powders were characterized by transmission electron microscope (TEM), Scanning electron microscope (SEM), Thermogravimetric analysis (TG), X-ray diffraction (XRD) and Fourier transmission infrared (FT-IR) spectrum. The photocatalytic performance of methylene blue by zinc oxide was studied based on the Langmuir model and Photo-Layer model. The results show that some zinc oxide powders were micro-multipore materials with hexagonal crystal. The particle size was around 32 nm. The photocatalytic process was the control step in the chemical reaction. The photo catalytic process followed pseudo-first order kinetics and •OH concentration inside the photo-layer in different reaction condition were calculated according to the Photo-Layer model.

This study continues an earlier work devoted to simulation of mass transfer in liquid-liquid systems taking into account mass transfer across fractal interfacial structures. Earlier, using methods of nonequilibrium thermodynamics, we obtained an expression for the generalized thermodynamic force taking into account colloidal chemical phenomena in the interfacial region, such as the formation of disperse interfacial layers and films. Here, using a differential equation with a fractional-order derivative, we estimate the diffusion coefficient of the extractable substance in the interfacial film and the porosity of this film, which is its structural characteristic.

A unit was designed for investigating the effects of low electrostatic fields on exchange reactions in extraction systems. The dynamics of oxalic acid transfer across the interface during the reextraction of copper ions under the action of copper oxalate deposition was studied. The peculiarities of reextraction dynamics were explained by the formation and migration of discontinuities in the copper alkyl phosphate film along the interphase surface under the action of an electrostatic field. The dynamics of the process is characterized by the appearance of specific exchange rate maxima and by a drastic decrease in the rate in the presence of an electric field.

In male willow ptarmigans, the relationship between qualitative differences between birds belonging to different intrapopulation groups and some individual features of male nuptial plumage has been revealed by studying banded birds. Thus, males that have changed their nesting site differ from those returning to the former site and bigamous males differ from monogamous in the number and size of dark spots amid the white plumage. The influence of the time of the onset of spring on the development of nuptial plumage is considered.

A mass transfer model in which the generalized thermodynamic force accounting for colloidal and chemical phenomena in the interfacial zone, such as the formation of disperse interfacial layers and films, is taken to be the driving force is considered. A method for calculating the difference between the pressures in the film and in the phase, the interfacial-film thicknesses, and mass transfer coefficients is proposed. It is found that the resistance to mass transfer in porous films varies with time, passing through a maximum.

The kinetics of heterogeneous hydrodynamic coagulation and coalescence of motor oil droplets 0.4–1.5 μm in size with a concentration of 0.15–0.5 vol % is investigated in a convoluted tube, a centrifugal pump, and their combination. Kinetic parameters of the coagulation-coalescence process, which proceeds hundreds times faster than sedimentation, are determined.

The mechanism of purification of an aqueous phase from droplets of Midel 7131 transformer oil with the use of heterogeneous hydrodynamic coagulation in the presence of a second organic solvent is considered. Models of heterogeneous hydrodynamic coagulation are proposed, and the simplest and most probable model variants are chosen.

A setup is designed to study the kinetics of heterogeneous hydrodynamic coagulation in the presence of a second organic solvent, which significantly accelerates the coagulation. Without coagulants, 5–20 min is sufficient to remove 80% of suspended transformer oil drops 2–10 μm in size. Addition of aluminum salts or ferrous salts to a concentration of 10−5–10−4 M increases the treatment rate by about an order of magnitude.

The Eley-Rideal and Langmuir concepts of surface reactions were used to develop a model of heterogeneous hydrodynamic coagulation of diluted “oil-in-water” emulsions (0.1–2.0 vol %). The mathematical model was verified, and factors that govern the coagulation rate were revealed.

A prototype reactor for heterogeneous hydrodynamic coagulation of emulsions was developed and tested. The efficiency of coagulation of water emulsions of some organic liquids was studied in relation to process conditions.

The kinetics of migration of monomolecular layers of surface-active extractants on water is studied. The problem is important in the context of radioactive contamination of the surface of water reservoirs and watercourses. The migration velocities of eight extractants used in the radiochemical industry and 37 systems containing these reagents are determined.

The migration velocities of surfactants on the surface of tap water are measured by the tracer method. The results are well reproducible, although the surfactants and the water are used without special purification. A decrease in the surfactant migration velocity with time was observed. It is found that the main cause of the decrease is an increase in the weight of the water adjacent to the surface film. The radial migration after a very short time is characterized by uniform surfactant motion.

The return of willow ptarmigans to the sites in which they nested the previous year has been studied using color banding. No factors influencing the return index have been revealed, except for its dependence in males on the time when spring begins in a given year. In northernYamal, in contrast to the temperate zone, some surviving birds fail to return to their former nesting sites. Polymorphism of individuals with respect to territorial behavioral strategy is proposed for L. lagopus populations at the northern boundary of the species range.

Automatic system for electrochemical monitoring of corrosion parameters of protective metal coatings described substantially accelerates analyses, making them much more reliable and reproducible.

The discovery and development of effective antihypoxic drugs is an important issue in modern experimental and clinical pharmacology. Complexes of zinc containing imidazole cycles as ligands are promising candidates for the design of novel drugs, including pharmacotherapeutic tools for patient’s protection under conditions of oxygen deficiency. Herein, we report antihypoxic activity of zinc complexes with N-alkenylimidazoles, and, specifically, a novel drug Acyzol, which can be used as efficient antidote after poisoning by carbon monoxide and other combustion products.

In this paper, Boolean functions f(x1,…, xn, z1,…, zm) are considered, where x1,…, xn are ordinary Boolean variables and z1,…, zm are improper Boolean parameters, i.e., indicators of external factors. Algorithms for designing a circuit of functional elements that realizes an indicator z ∈ lz1,…, zmr are presented.

The influence of surfactants and temperature on the intensity of interphase mass transfer in back extraction under conditions of forced Marangoni flows was studied.

Проведено сравнительное исследование абразивной износостойкости стали Х12МФ после упрочнения с использованием термической обработки и технологии нанесения наноструктурированных PVD-покрытий в сочетании с последующим криогенным воздействием. Лабораторные исследования и эксплуатационная апробация предложенной упрочняющей технологии показали, что использование криогенной обработки является эффективным средством повышения ресурса (износостойкости) инструмента из стали Х12МФ, и данный вид обработки можно рекомендовать к более широкому промышленному использованию. Технология предусматривает охлаждение металла, прошедшего закалку и отпуск, до температуры жидкого азота, выдержку при этой температуре и последующий низкий отпуск. Образцы, подвергнутые криогенной обработке, менее чувствительны к увеличению абразивной зернистости, при этом характеристики износостойкости образцов на 19-22 % выше по сравнению с образцами после термообработки. Технология нанесения наноструктурированных PVD-покрытий позволяет повысить износостойкость на 51-66 % по сравнению с технологией термообработки образцов и на 38-59 % по сравнению с криогенной обработкой. Комбинированная технология нанесения PVD-покрытия и криогенной обработкой позволяет получить прирост износостойкости на уровне 61-71 % по сравнению с термообработкой и на 14-20 % по сравнению с PVD-покрытием без криогенной обработки.

The charge-exchange reaction K + Xe → K 0 pXeis investigated using the data of the DIANA experiment. The distribution of the pK 0 effective mass shows a promi- nent enhancement near 1538 MeV formed by nearly 80 events above the background, whose width is consistent with being entirely due to the experimental resolution. Under the selections based on a simulation of K + Xe collisions, the statistical signif- icance of the signal reaches 5.5�. We interpret this observation as strong evidence for formation of a pentaquark baryon with positive strangeness, � + (uudd¯), in the charge-exchange reaction K + n → K 0 p on a bound neutron. The mass of the � + baryon is measured as m(� + ) = 1538 ± 2 MeV. Using the ratio between the num- bers of resonant and non-resonant charge-exchange events in the peak region, the intrinsic width of this baryon resonance is determined as ( � + ) = 0.34±0.10 MeV.

It is established that the modifier content — chemically modified bottoms from the distillation of kaprolaktam (MBDK) — plays a considerable role in the liquation of ceramic green mixes. Liquation occurs for 0.5 – 1.0% MBDK, while above 1.0% the clay surface becomes hydrophobic as a result of its interaction with organic matter. Electrolytes, surfactants, water-soluble salts, as well as various plasticizers influence the properties of clayey suspensions and the structural and rheological properties of ceramic green mixes. Organic matter and plasticizing additives are widely used in various areas of ceramic technology to stabilize and improve the properties of water solutions, impart to the required molding properties of the plastic molding mixes based on clay-containing initial materials and nonplastic materials, as well as giving the required strength to the molded blanks in wet and dry states. At the same time superplasticizers are being more widely used and new modifiers based on reliable raw materials resources and wastes from the chemical industry are being developed [1 – 3]. We propose a new modifier for clays and clayey suspensions which is based on wastes from the production of kaprolaktam — chemically modified bottoms from the distillation of kaprolaktam (MBDK), whose composition and chemical structure were determined in previous investigations. The modifier obtained is a salt with a polymeric cation and anion of mineral acids. The general formula of the modifier has the following form: –[ HN 2 – (CH 2 ) 6 –C– ] n X – , || O where n = 1 –5 , andX – is the anion of the acid (Cl – , NO 3

Experimental evidence was obtained in favor of the existence of the fine structure of the interface region in the liquid-liquid system far from equilibrium. The predominant interface phenomenon in the liquid-liquid system proved to be the formation of dispersed layers, whose occurrence and evolution determine the mass and momentum transfer through the interface.

The hydrodynamics and kinetics of CO2 absorption by water when the interface is disturbed by partially immersed disks that execute torsional oscillations or uniform unidirectional motion (rotation) was studied. It is shown that interface disturbance and generated surface flows enhance mass transfer by a factor of 2.5 and lead to extremum dependences of the mass transfer coefficient on the area and thickness of the insoluble film covering the water surface. The surface flows generated by disks at the gas-liquid interface were examined. Two types of surface flows that differ by their direction and the nature of driving forces are revealed. The role of these flows in enhancing mass transfer at small Re numbers was elucidated.

Oil-in-water emulsions at concentrations of 0.001‐ 1 vol % are very important objects because they are involved in fine water treatment to remove oil microdrops and in the formation of cruds, which cause a nuclear hazard in radiochemical extraction processes. In this work, a method was proposed for studying the coalescence of microdrops of organic liquids on the surface of solids and cloths. It was shown that the determining step is a second-order process occurring on the collision of microdrops coming from the bulk with drops of surface clusters. Once the microdrop size has become smaller than a certain value, the process rate constant significantly decreases. It was found that the decisive role in the microdrop coalescence is played by the pH of the oil-in-water emulsion and the specific surface area of solids. The proposed mechanism accelerates the separation of oil drops from water by a factor of hundreds or thousands.

Стаття присвячена проблематиці повсякденного життя у таборах переміщених осіб (т.зв. ДіПі) упродовж 1946-1947 рр. в американській зоні окупації Німеччини. Визначено головні особливості устрою післявоєнного соціального середовища окупованої Німеччини, що були пов’язані із цілим комплексом соціально-економічних та політичних обставин. Використовуючи історичні джерела 1945-1947 рр. (матеріали преси, звіти чиновників ЮНРРА, рапорти фахівців громадських організацій) встановлені основні побутові тактики життя переміщених осіб в таборах ДіПі. Практика табірного повсякдення розглянута на прикладі матеріалів із приватного архіву родини В. Елліса – харківського інженера та поета, що упродовж зазначеного періоду часу разом із своїм другом, художником В. Одіноковим випускав самвидавний альманах «ДіПІніада». Встановлено, що альманах як візуальне джерело має надзвичайно цінну контекстуальність. Коло тем, що показані у «ДіПініаді», дозволяють істотно якісніше описати побутові та повсякденні практики взаємовідносин місцевого німецького населення із біженцями, американської окупаційної адміністрації із колишніми в’язнями німецьких концтаборів тощо та проаналізувати увесь складний вузол протиріч та взаємин, який становить основний зміст подій 1945-1947 рр. в американській зоні окупації Німеччини. Зауважено, що дослідження має подальшу перспективу щодо аналізу історії повсякдення у контексті візуальної антропології джерел, які є водночас мистецьким та літературним явищем свого часу.