bluuebunny/crossref_metadata_2025 huggingface dataset:
Gas generation by coal matter in contemporary conditions
Authors: Bezruchko Kostiantyn , Burchak Oleksandr , Balalaiev Oleksandr
Published: July 2019

A new approach for the study of processes at the atomic-molecular level occurring in the current situation in fossil carbonized organics was proposed. A new phenomenological model of physicochemical transformations in a metastable coal substance with the emission of fluids has been developed. The proposed physic/chemical model is based on the genetic connection of coal methane with fossil organic matter and determines the conditions for the activation of structural transformations in coalmines. This model describes the possible options for the coal/gas system development in the current situation. The accumulation of thermal and mechanical energy by coal in the form of structural stresses in an amount, sufficient to activate free-radical reactions, was experimentally established. In the undisturbed coalrock massif the processes of the coal molecular structure transformation have the relaxation character. The result of relaxation of the accumulated energy in the conditions of a gas-saturated coalrock massif is the methane generation by coal. Gas generation in the process of coalification, in its essence, is the energy response of the system to the action of external geomechanical options (temperature and pressure), by the way of releasing the accumulated additional energy with the emission of gaseous products and the destruction of the solid phase in the organic matter of the coal.
Analysis of tectonic deformations dynamics on the example of the area of the south-west wing of Kalmius-Toretsk kettle hole
Authors: Bezruchko Kostiantyn , Diachenko Natalia , Diachenko Anna
Published: July 2019

The article presents analysis results in the reconstruction of the tectonic conditions dynamics for the formation of local plicative deformations and rupturing under conditions of the research both the macrostructure and its local separation using the example of the southwestern area of Kalmius-Toretska kettle-hole in the Donetsk basin. Authors applied the scientific cognition method, representing a sequence of actions to establish structural links between variables and constant elements of the Investigational tectonic system, based on statistical and mathematical methods of analysis. The characteristics of the anticlinal structure formation in the studied area - fields of the “Butivska” mine were obtained. It was revealed that the initial horizontal attitude of rocks of the studied area was changed by a monoclinal attitude with a north-western dip and a north-east strike. Afterwards, under the conditions of tectonic near latitudinal compression and near meridional tension, anticlinal folding was formed. Then, under the influence of shear fields when the deformation mode was enhanced, a compression duplex was formed within which local echelon folding and fracture was formed - Oktiabrskyi fault #1.
Pop-up structures of Petrodonetska anticline and adjacent territories
Authors: Diachenko Natalia , Diachenko Andrii
Published: July 2019

Presents the results concerning a comparative analysis of paleotectonic reconstructions of the tectonic conditions dynamics for the formation of local plicative deformations and faulting in the study of the macrostructure and its local separation using the example of the Almazno-Marievskyi region. The formation conditions characteristics of the Petrodonetska anticline and adjacent territories were obtained. In the plan, they are located en echelon-like, which is associated with a shift. The structure of the latter indicates a thrusting of the sedimentary stratum layers from the center of the Donetsk trough to its northern periphery. The analysis of reconstruction results regarding the formation of the Lysychanska anticline on the border with the Severodonetskyi thrust and sections in experimental research of pop-up structures, reveals their similarity in structure and formation. With oblique convergence of blocks from the shear zone, a series of overlapping thrusts are extruded. A central graben arises within the transpressive shear zone, along its axis due to the divergent reverse faults in the arched uplift. A system of parallel thrust faults forms a ramp. The necessity of using the system modeling method (the finite element method), which improves the methods for predicting gas-containing tectonic elements in the pop-up structures, is justified.
Substantiation of the effectiveness of the hydro-steam turbines application in mine power complexes for excess heat recovery
Authors: Diakun Inna , Kirsanov Mykhailo , Ruban Vitalii
Published: July 2019

The main problems connected with an increase in the performance efficiency of the mine power complexes, should include issues of rational use of fuel in power facilities, as well as the maximum consumption of produced thermal and electrical energy. One solution to this problem has been proposed to use in schematic solutions the reaction-type hydro-steam turbine for excess heat recovery of and generation of additional electrical energy. The condition has been set in the article for the choice of the configuration of a hydro-steam turbine nozzle with a high efficiency of energy conversion, as well as the variants have been studied of principle schemes for energy complexes: the scheme for a power facility, consisting of a gas-reciprocating module, on the shaft of which a module with a hydro-steam turbine is set, as well as the scheme for a module placement of back pressure turbine and hydro-steam turbine on the same shaft with a gas-reciprocating module. A comparative analysis has been performed of energy efficiency of the proposed principle schemes for the energy complexes.
Ground parameters of working standard of reproduction of small speeds of air stream
Authors: Dudnyk Mykhailo , Veretennyk Viktor , Enhel Serhii , Krytskyi Vadym , Myroshnychenko Vadym
Published: July 2019

As a working standard for research in the area the lowest air velocity can be used a rotary stand. In Ukraine it was not standard measuring instruments of low speeds of air flow. Used Ukrmetrteststandart the Pito-Prandl model pressure tube has a precision class of 0.5, but the range of measurements start only with 5 m/s. In the Institute of Geotechnical Mechanics named by N. Poljakov of National Academy of Sciences of Ukraine was developed, created and perfected the standard stand RESVP-1, which allowed the creation of small air velocities. The considered method of aeromechanical measurements at low velocities of air flow provides the possibility of a very accurate setting of the speed of the crowding airflow affecting to the object under study, since in this case it is a linear velocity of movement the object being studied in motionless air. In the crowding flow affecting the object under study, no pulsations and vortices distorting the measurement results. Standard RESVP-1 is certified by standardization bodies Ukraine in the range of values of reproducible speeds from 0.000 to 1.200 m/s with the permissible value absolute error +(0.001 + 0.003V), where V is the reproducible flow velocity, m/s.
The feasibility evaluation of using cyclic thermal effect in the rock-cutting tools during drilling hard rock
Authors: Hankevich Valentyn , Moskalova Tetiana , Kabakova Liudmyla , Livak Oksana
Published: July 2019

The possibility of using cyclic thermal effect in drilling tools for softening of rocks is considered in the article. It is shown that during drilling in the phase of heating, the rock sections can actually be heated to 1000 °C, and it is possible to achieve even higher temperatures with the use of corresponding frictional heating elements. It has been found that the phase of cooling of the heated section of the rock can ensure guaranteed cracking of the rock for subsequent mechanical destruction.
Studying and improving intermediate rail fastening of rail transport
Authors: Hovorukha Volodymyr
Published: July 2019

Topical problem concerning the improvement of intermediate rail fastening of a railway track of railroad transport as well as industrial and underground rail one has been considered taking into account peculiarities of operation in terms of curved sections of a route with small-radius curvature. Objective of the paper is to improve operational parameters of a railway track with extra small curvature radii in terms of railroad gauge adjustment. Operation of the components of intermediate rail fastening, being subject to intense wear and destruction due to the effect of great transverse and horizontal loading within the curved route sections with small-radius curvature, has been and analysed. Innovative engineering solutions to improve intermediate rail fastening have been proposed. Such peculiarity of the device of intermediate rail fastening provides increased durability and working capacity of rail fastening components in terms of considerable transverse loading within the route sections with small-radius curvature. The obtained results may be applied for underground and industrial rail transport as well as for railroad one.
Movement stability of vehicles with a rigid and free wheels mounting on wheelset axles
Authors: Hovorukha Volodymyr
Published: July 2019

The article considers the actual task of improving mobile units of underground rail transport, taking into account the peculiarities of work in straight and curvilinear sections of the path of especially small curvature radius of 8–50 m, with reference to the rail track width of 600; 750 and 900 mm. The purpose of the work is to improve operational performance of rail transport of mining enterprises and improve safety of railway movements. Methods for the study of interaction processes of mobile vehicles and the rail track are presented. The study results of loading, oscillations and movement stability of vehicles with the free and rigid mounting of wheels on the axles of wheelsets are given. The resonance phenomenon due to the proximity of frequencies of forced and natural oscillations of mobile units of underground rail transport has been established. The obtained results can be applied to the development of normative documents regulating tolerances for the maintenance of rail track in the plan, profile and for the broadening of the track, taking into account the vertical, horizontal and longitudinal irregularities of the rail threads. The study results can be used to improve the design of mobile vehicles and rail track.
About trends of improvement of technological schemes for methane recovery from the rock-coal massif
Authors: Kurnosov Serhii , Zerkal Volodymyr
Published: July 2019

Purpose of the research was to improve efficiency of underground gas drainage from the rock-coal massif. It is substantiated that most promising solution of the problem of increasing efficiency of gas drainage from the massif is to mine additional gas-drainage road. This approach allows separating processes of coal mining and methane recovery in space and time. The Ukrainian normative documents is recommended to mine the road behind zones with high rock pressure. We found that in difficult conditions of coal seam mining, distance from road to working long wall would be more than 100 m. This distance reduces efficiency of gas drainage and is not economically feasible due to significant length of gas-drainage boreholes and air breakthroughs. Therefore, gas-drainage road should be located as close to the working long wall as possible, but with possibility to ensure its stability during its entire service life. Experimental studies were conducted in Zasyadko Mine and Krasnolymanska Mine. It is established that with increasing distance from working wall to the gas-drainage road location in the massif, unloaded by the under working displacement, the road contour decreases, and methane flow rate increases in power dependencies. Use of these results will make calculation of the gas-drainage road rational location more accurate.
Method for determining the rational parameters of dynamic dampers of low-frequency vibrations
Authors: Lapshyn Yevhen , Molchanov Robert , Khaminich Oleksandr
Published: July 2019

The problems have been considered of natural nonlinear vibrations of an absolutely rigid semiball and a semicylinder on a horizontal plane, assuming that there is no energy dissipation, sliding and tipping on foundation. To adjust the damper to a frequency close to the fundamental tone of vibrations, it is necessary to assess the natural frequency of the damper, which is determined under the assumption on smallness of the vibrations amplitude. This paper represents the comparison of the natural frequency of linearized and nonlinear system. The relative error has been estimated of the natural frequency calculation, which is caused by linearization. It is shown that the ratio of the natural frequency of the linearized system to the natural frequency of the nonlinear system does not depend on the mass and radius. This conclusion made it possible to generalize the results of particular computational solutions and to obtain a formula which takes into account the amplitude influence on the natural vibrations frequency and helps to determine the natural frequency for the initial angles to ninety degrees.
On the oscillations of spatial vibration-isolating system of mining machines under the action of impact loads
Authors: Lysytsia Mykola
Published: July 2019

Theoretical and experimental results concerning interaction between lumpy loads and loading sections of a belt conveyer have been represented. The rational parameters of the loading section of the conveyor belt are determined from the point of view of reducing the amplitude of oscillations after the interaction. The regularities of oscillation amplitude of a loading section after interaction with a single lump have been identified.
On the effect of the direction of external load application upon the change in stiffening behavior of rubber vibration isolators
Authors: Lysytsia Mykola , Ahaltsov Hennadii , Lysytsia Natalia , Novikova Alina
Published: July 2019

The paper represents experimental results concerning determination of stiffening behavior of rubber vibration isolators depending upon the direction of external load application as well as fastening conditions. Paying attention to the fastening technique makes it possible not only to widen the area of application for vibration isolators, but to reduce the range of the ones being manufactured.
Effect of water medium upon the process of ore disintegration in wet self-grinding mills
Authors: Monastyrskyi Vitalii , Monastyrskyi Serhii , Mostovyi Borys
Published: July 2019

This article presents the results of theoretical and experimental studies on the processes of destruction ore in wet self-grinding mills under the influence of the aquatic environment on it. The equivalent circuit for determining the stress-strain state of a large piece (ball) exposed to the load at an angle of repose of the material in motion are justified. A uniformly distributed pressure acts on the body of arbitrary shape, depending on the hydrostatic pressure of the pulp inside the drum and the force of hydrodynamic resistance). It is assumed that a large piece has the shape of a sphere with a uniform structure, but in some of its parts there are cavities filled with an incompressible fluid. Under the action of these forces inside the cavity wedging effects of water occur, the effect of which on the strength ores depends on the expansion force and the angle of the micro crack. The experimental researches are done under laboratory and industrial conditions. It was established that the disintegration of kimberlitic ore in MMC is significantly influenced by the characteristics of the aquatic environment pH and Eh, the values of which vary from 3.2 to 7.0 and from -500 to +1020 mV.
Influence rocks mass and explosives properties on dissipative energy losses during blasting
Authors: Nykyforova Valentyna , Yefremov Ernest , Kratkovskyi Ihor , Kurinnyi Volodymyr
Published: July 2019

The factors affecting the energy explosion loss on rock crushing on con-tact with explosives have been established. This makes it possible to substantiate ways to increase low explosion efficiency. Theoretical estimates of the explosion energy losses during the rocks destruction have been carried out taking into account the explosives properties and heterogeneities in the rocks structure. It has been established that homogeneities in the form of mineral grains of various strengths determine the mechanism of their destruction and crushing during blusting. A thermodynamic loss has been estimated during the expansion of gaseous detonation products, on which the maximum explosion work depends. These losses characterize the theoretical possibility of the transfer of energy stored in an explosive into mechanical work. The explosion losses associated with the origination of shock waves in rocks are also have been determined.
Energy efficiency of cogeneration utilization of residual heat of flue gases during the drying of coal concentrate in pipe-dryers
Authors: Oksen Yurii , Radiuk Maksym , Komissarov Yurii , Kirsanov Mykhailo
Published: July 2019

The possibility of increasing the efficiency of drying coal concentrate unit on the basis of pipe-dryers has been investigated by converting the heat of flue gases outlet into electrical energy and the heat potential of hot water supply system with a heat power generation unit operating on low-boiling working fluids. A method and an algorithm for calculating the thermal mode of the unit under the conditions of specified limitations on temperature pressures in heat exchangers have been developed. On the basis of mathematical modeling of thermal conditions, it has been found that under the conditions of PD-11 pipe-dryers, when the heat power generation unit operates with butane-pentane mixture, 204 kW of electricity can be generated with the condensation cycle, and 1780 kW of heat and 65 kW of electric energy can be generated with the heating cycle.
Determining integral permeability of undermined coal rock mass in closed mines
Authors: Prykhodchenko Oleksii , Prykhodchenko Svitlana , Tokar Larysa
Published: July 2019

Effect of mining on pressure variation in coal rock mass has been analyzed. Methods to determine integral permeability as well as fluid pressure variations within undermined coal rock mass have been proposed. A technique to identify zones of “fast” gas and “slow” gas within undermined formation has been considered.
Geological factors of gassing of the east inclined longwall # 3 of m3 bed at O.F. Zasiadko mine
Authors: Pymonenko Liudmyla , Karhapolov Andrii , Kuznetsova Liubov , Prykhodchenko Oleksii , Hunia Dmytro
Published: July 2019

The paper deals with the fact that gassing of the East inclined longwall (EIL) # 3 of the m3 bed at the «O.F. Zasiadko mine» are caused by a combination of mining-geological conditions. The main geological factor is the presence of a synclinal fold, characterized by increased fracturing. The map construction of local structures, the use of gravity data and seismological observations allow to effectively isolate gas-saturated zones and, therefore, correct degassing projects and parameters of ways to prepare workings.
Successive approximation method applying to obtain the transient elastic medium deformations
Authors: Sapehin Volodymyr
Published: July 2019

Therein used the well-known method of successive approximation of functions for solving the problem of transient deformation of an elastic medium under the influence of variable internal pressure in wells in paper. The desired function – the maximum tensile stresses – is represented as a product of power functions, each of which depends on only one parameter. The regularity of changes in the maximum tensile stresses and the main factors influencing this process, which is fully confirmed by the independent theory of dimensions, are established.
Defectoscope for monitoring of a concrete timbering of underground constructions
Authors: Serhiienko Viktor
Published: July 2019

The purpose of work is development of a defectoscope for nondestructive identification of spaces in rock mass on border with a concrete timbering. The principle of operation of the device consists in the analysis of parameters of vibration of a timbering after drawing blow to it. The difference from the known developments consists in contactless reception of an acoustic signal with use of the microphone. Parameters of vibration of a timbering are determined under various conditions of its contact with rock mass. Initial requirements for development of a defectoscope are experimentally defined. Its block diagram is submitted and principal specifications are given. Data on approbation of the equipment in hydraulic engineering constructions are given.
Justification of the basic algorithms of the mine safety information system
Authors: Shevchenko Volodymyr , Slashchov Anton
Published: July 2019

This article is devoted to substantiation of basic algorithms for the information system which could provide prompt making of decisions on ensuring safety of underground mining jobs, which are of great importance for the job safety at the mining enterprises. The information safety system architecture and some basic algorithms was developed. The system differs by its methods for prompt predicting and assessing of different scenarios of geomechanical process development, and which includes the following subsystems: a basic client-server subsystem with functions of interaction between the personnel and management of the enterprise; a reference and information subsystem, which supports a decision making process, accumulates data and analyzes technical documentation; a subsystem for analyzing the job safety by geomechanical factors and for assessing of the “support-rocks” system state basing on the risk criteria and mathematical fuzzy logics. Two integral indicators of safety are formed. The first indicator is used to control entering of the control object to the emergency mode and to determine a factor, which requires urgent interruption, and the second indicator is used for the total assessment of the object current state.
Specific solution of problem of water filtering in the rocks by the finite element method
Authors: Slashchova Olena , Slashchov Ihor , Sapunova Iryna
Published: July 2019

The article is devoted to development of methods for geofiltration calculations with taking into account peculiarities of changes of the rock physical and mechanical properties at water saturation. Methods: mathematical modeling of geomechanical and filtration processes with the help of finite element method and laboratory and underground studies. A mathematical model was formulated for solving a problem of elasticity theory by the finite element method, which took into account peculiarities of water-saturated rocks. Pattern of stress-strain state changing in the fractured water-saturated rocks under the action of critical loads, which occurred around the preparatory roadways during their operation, were established. In order to solve the filtration problems, a bank of collected initial data on physical and mechanical properties of water-saturated rocks was processed with the help of variation coefficients, which were taken into account by the method, which assumed calculation of the model loading with critical parameters.
Estimation of fracture systems parameters in rock massif by the finite element method
Authors: Slashchov Ihor
Published: July 2019

Results of analytical, laboratory and mine studies of parameters of disintegration zones in structurally-heterogeneous rocks and fracture systems around of the deep mine roadways are presented. A mathematical model is proposed, which is realized with the help of the procedures of simulation modeling by finite element method. Based on the calculation of possible directions of the rock shearing (the “rock shear sites”) and breakage of bonds between the elements, the model allows determining orientation of dominant master fracture system development with taking into account natural structural defects in the rock massif. A new algorithm was created for determining master cracks and boundaries of disintegration zones with the layered rock, which differs by determining directions of rock shear sites in the elastoplastic problem considering residual strength and main structural defects of the structurally-heterogeneous rock massif. Regularities of organization of unidirectional rock shear sites and their distribution under the influence of mining operations in zones with inelastic deformations were established.
Belt conveyers rollers average term of service
Authors: Smirnov Andrii , Beihul Vsevolod
Published: July 2019

The paper is proved to one of the important conveyer transport system task – to roller’s term of service (TS) determination. The task solving permit to evaluate the different designs belt conveyers reliable. The article represent the tasks of belt conveyers roller’s average TS determination were set and solved for the different types of roller supports. Dynamic efforts arised with the loading motion and caused with belt bend are principal factor for the calculation of TS rollers. The graph of dependence roller’s average TS from belt velocity for different roller’s types were obtained. Obtain analyses results permit to set: average roller TS decrease under velocity increases for all types of roller’s, TS for dumping overhead roller supports and damping roller supports is substantially greater, then for hard and overhead roller supports. In addition, at some values of the belt velocity TS service can sharply decrease for all types of roller supports. It takes place in resonances related to vibrations of belt at motion of large pieces of load. Achieved results may be applied in mining, metallurgical and building industry.
A thermomechanical technology of borehole wall isolation using a thermoplastic composite material
Authors: Sudakov Andrii , Dreus Andrii , Kuzin Yurii , Sudakova Diana , Ratov Boranbay , Khomenko Oleh
Published: July 2019

Loss of drilling fluid in wells is one of the most important drilling challenges. To prevent this problem an insulation of borehole wall is requiring. The results of study of an innovative technology of isolation of borehole using a new thermomechanical plugging material are presented herein. The material considered is solid composite consisting secondary polyethylene terephthalate and gravel. Theoretically and experimentally shown the possibility to use this material to borehole isolation. The technology of manufacturing and isolation of absorbing horizons by thermomechanical material has been developed. Dependence of the regime parameters of thethermomechanical process melting of material on the thermophysical properties and technical characteristics was established. Dependence of the penetrating ability of material melt on the fractures was established. The results of work can be used to recommend technology parameters providing the efficient melting rate.
Determination of porous structure parameters of coal particles to describe thermal conversion processes
Authors: Topal Oleksandr , Holenko Iryna , Diakun Inna
Published: July 2019

The results of determination of parameters of porous structure of coal and char particles are presented. They were determined using gas adsorption method and thermal decomposition of particles in air oxygen. The porous structure parameters allow predicting char reactivity change at different temperatures as well as during conversion in accordance with Random Pore Model (RPM-model).
Investigation of the fluids influence on change of sandstones collectors mechanical properties during saturation and degassing
Authors: Tynyna Serhii , Babenko Vasyl
Published: July 2019

The article discusses the effect of fluids on the properties of rocks. It is known that surface active environments, including gas, can significantly change the mechanical characteristics of solids. To establish the dependence of the effect of methane on the strength characteristics of rocks, the results of full-scale and laboratory studies are considered. The experiments were carried out on samples of outburst sandstone formation m3, taken at a depth of 915 m. Analysis of research results allowed to establish the effect of changes in gas saturation of rocks on their mechanical properties before and after degassing and partial discharge of experimental areas after they have been worked by lavas along m3 formation. It has been established that the reason for the increase in drillability and strength of sandstones was their degassing, and not a change in the stress state of the environment. This led to a change in the deformation properties of rocks in gas-saturated and degassed states.
Mathematical model of the cracking process in the coal-rock massif under hydrodynamic impact
Authors: Vlasenko Vasyl , Dudlia Kateryna , Kyrychenko Maryna
Published: July 2019

The physics of hydrodynamic impact (HDI) is in the softening of the coal seam due to the generation of alternation stress in it. Stress is carried out due to injection and discharge of fluid into the coal seam in the filtration mode. The mathematical model of the processes occurring in the coal massif under HDI was developed. The model allows to determine the nature of the coal destruction in forward and inverse filtering of fluid in the massif. Cracking in the process of fluid filtration is achieved while simultaneously fulfilling two criteria: power and energy.
Response of oscillatory system “liquid layer-rod” to driving disturbances
Authors: Yelisieiev Volodymyr , Lutsenko Vasyl , Shevchenko Serhii , Shevchenko Anatolii , Tolstopyat Oleksandr , Fleer Leonid
Published: July 2019

This article deals with main characteristics of the oscillating system “central body – liquid” by means of its well-known representation in the form of a pendulum mathematical model. It makes possible to evaluate spread of specified disturbances at the general physical level and to determine the most dangerous frequencies that lead to increased amplitudes of fluid oscillations. We propose equations for single-frequency pendulums, which influence each other by means of resistance forces and added mass. Several examples with different natural frequencies of the body are considered. The calculation results showed that besides natural frequencies of the components, system has two more natural frequencies. So, system actually responds only to disturbances which frequencies are close to the natural frequency of the liquid layer. In this case, amplitudes of liquid and the body sharply increase. This fact indicates that in real technological processes frequency of dominant disturbance should be as far from the first resonant frequency of the liquid as possible. The further experimental and theoretical studies that take into account the influence of the following modes on the dynamic picture of the process are also of interest.
Evaluation of the cavitation generator efficiency in the hydro impulsive loosening of a coal-bed
Authors: Zberovskyi Vasyl , Zhulai Yurii , Mirnyi Serhii
Published: July 2019

The paper presents the results of mining and experimental work, bench tests and theoretical studies of the energy characteristics of the stationary and pulsating fluid flow, which allow to estimate the efficiency of the cavitation generator in the hydro impulsive loosening of an outburst-prone coal-bed. The active stage of the hydro impulsive loosening and the effective range of the amplitude-frequency (AF) spectrum of the generator operation acoustic signal have been established by the AF spectrum of the sound accompaniment of the hydro impulse impact and the backup pressure of the liquid in the well. By calculation for this range the energy characteristics of the static and dynamic components of the pulsating fluid flow were determined. This made it possible to determine that the efficiency of the cavitation generator, all other conditions of the coal-bed hydro loosening being equal, is 4.8–1.2 times higher than the efficiency of the static impact.
Application of the method of observing the natural impulse electromagnetic field of the Earth to trace watered faults on the example of Yeristovo quarry
Authors: Zmiievska Kristina , Tubaltsev Oleksandr , Zmiievskyi Artur
Published: July 2019

The article presents the results of applying the express method of observing the natural impulse electromagnetic field of the Earth to isolate flooded faults in areas adjacent to the Yeristovo quarry. The features of the geological and tectonic structure of the territory of the Yeristovo field are considered. According to the results of the field studies, for the first time, maps of the density of the natural impulse electromagnetic field of the Earth flux were constructed for this area, which made it possible to isolate and trace the positions of watering faults. In addition, to visualize the most difficult fragments of the structure of the plots, three-dimensional models were built. On the basis of the conducted research, it is possible to recommend the use of water catching wells using a reasonably economical and reliable method of observing the natural impulse electromagnetic field of the Earth. It is advisable to lay them in the zones of minimum values of the natural impulse electromagnetic field of the Earth, within the southern parts of the research sites. The use of advanced observations will avoid unproductive costs when drilling water-reducing wells.
Préservation osseuse et temporisation prothétique par mini-vis dans les cas d’agénésies des incisives latérales
Authors: Onghena Tom , Breton Olivier , Leclercq Pierre
Published: July 2019

En cas de réouverture d’espace dans les situations d’agénésie(s) d’incisive(s) latérale(s), les solutions de temporisation prothétique à la suite du traitement orthodontique ont été maintes fois publiées : l’évolution actuelle tend à faire du bridge collé cantilever le gold standard. Il faut toutefois noter que ce moyen thérapeutique ne permet pas une stimulation de la crête osseuse édentée, et que cette dernière se résorbe inéluctablement, compromettant ainsi la prise en charge implantaire ultérieure et/ou le résultat esthétique à moyen et long terme. Nous allons décrire ici une technique originale de temporisation, permettant de stimuler la crête osseuse tout en assurant le maintien de l’espace de façon esthétique.
Aktivitäten im anterioren Hippocampus als Biomarker für affekt-basierte Therapien bei Posttraumatischer Belastungsstörung und Panikstörung?
Authors: Zimmermann Tanja
Published: July 2019

Posttraumatische Belastungsstörungen (PTBS) und Panikstörung (PS) sind häufige psychische Störungen mit überlappenden Symptomen wie Panikattacken, hohem Angstniveau, Emotionsregulationsdefiziten sowie Vermeidung von aversiven Stimuli. Erfolgreiche Behandlungen sind Expositionstherapien sowie affekt-fokussierte Behandlungen. Der Hippocampus spielt eine bedeutende Rolle bei der Psychopathologie und dem Behandlungserfolg. Diese Studie untersucht die Zusammenhänge zwischen der Aktivität einzelner Hippocampusregionen und dem Behandlungserfolg bei PTBS und PS.
Mikrobiota und Reizdarmsyndrom – eine kritische Bestandsaufnahme
Authors: Enck Paul , Mazurak Nazar
Published: July 2019

Dieses narrative Review beleuchtet kritisch die Rolle der Darmmikrobiota bei funktionellen Störungen vom Typ Reizdarmsyndrom. Ausgehend von Veränderungen der Zusammensetzung und Vielfalt der Mikrobiota, wie sie oft in korrelativen Studien gefunden wurden, stellt es kritische Fragen nach Ursache/Wirkung, nach Spezifität und Sensitivität der Befunde im Vergleich zu anderen Erkrankungen und nach den klinisch-wissenschaftlichen Möglichkeiten, die Mikrobiota zu verändern. Dabei werden Prä-, Pro- und Antibiotika ebenso diskutiert wie der Einfluss von Ernährung und der Austausch durch fäkalen Mikrobiom-Transfer (FMT). Für das Reizdarmsyndrom haben sich bislang die wenigsten Strategien als erfolgreiche Therapieansätze erwiesen. Dies kann zum einen an der Heterogenität des Krankheitsbildes selbst liegen, zum anderen an nach wie vor unklaren Konzepten der mikrobiellen Forschung, z. B. dem Begriff der Dysbiose, oder an methodischen Differenzen der molekulargenetischen Forschung, die in den publizierten Arbeiten nicht sichtbar werden. Künftige Studien sollten sich auf die Identifizierung der Faktoren konzentrieren, die das Ansprechen auf solche Behandlungsarten erklären und vorhersagen können.
Aktuelle Aspekte zur Fotodokumentation in der Plastischen Chirurgie und deren Veröffentlichung
Authors: Motamedi Melodi , Hegemann Jan , Allert Sixtus
Published: July 2019

Bei der Erstellung von Patientenaufnahmen und deren Verbreitung bzw. Veröffentlichungen sind vielfältige Rechte betroffen, die beachtet werden sollten. Es ist unerlässlich zu wissen, wann tatsächlich eine schriftliche Einwilligung des Patienten vorliegen sollte und wann nicht. Entscheidend ist auch, dass trotz einer vorliegenden schriftlichen Einwilligung des Patienten, Gesetze im deutschen Rechtsystem existieren, die darüber hinaus eine Veröffentlichung reglementieren. Dies ist ein schwierig zu durchschauendes juristisches Thema, welches viele ärztliche Kollegen verunsichert. In der folgenden Übersichtsarbeit haben wir versucht die von dieser Thematik betroffenen wichtigsten Gesetze verständlich in einem nachvollziehbaren Zusammenhang zu bringen.
Clinical Outcomes of Posterolateral Complex Reconstruction Performed with a Single Femoral Tunnel
Authors: Helito Camilo Partezani , Sobrado Marcel Faraco , Giglio Pedro Nogueira , Bonadio Marcelo Batista , Pécora José Ricardo , Gobbi Riccardo Gomes , Camanho Gilberto Luis , Angelini Fabio Janson
Published: July 2019

The objective of this study is to report the functional outcomes, complications, and reconstruction failure rate of patients undergoing posterolateral complex reconstruction with a single femoral tunnel technique. Patients with posterolateral complex injuries associated with injury of the anterior cruciate ligament (ACL), posterior cruciate ligament (PCL), or both undergoing surgical treatment with the single femoral tunnel technique were included in the study. The International Knee Documentation Committee (IKDC) and Lysholm's scales were evaluated, in addition to age, gender, time between trauma and surgery, trauma type, range of motion (ROM) restrictions, peroneal nerve injury, and reconstruction failure. Sixty-six patients were included. Eighteen underwent ACL and posterolateral complex (PLC) reconstruction (group 1), 24 underwent ACL, PCL, and PLC reconstruction (group 2), and 24 underwent PCL and PLC reconstruction (group 3). The mean follow-up was 63 months. The subjective IKDC was 83.7 ± 14.6 for group 1, 74.3 ± 12.6 for group 2, and 66.3 ± 16.0 for group 3 (p < 0.001). The Lysholm's score was 87.1 ± 12.8 for group 1, 79.5 ± 15.0 for group 2, and 77.7 ± 15.2 for group 3 (p = 0.042). There were six reconstruction failures among the patients (9.1%) with no differences among the groups (p = 0.368). Female gender and reconstruction failure were associated with worse outcomes. Patients undergoing reconstruction of PLC structures with the single femoral tunnel technique achieved good functional outcomes and a failure rate similar to literature. Patients undergoing only combined ACL reconstruction showed better outcomes than patients undergoing combined PCL reconstruction. Female gender was associated with a worse functional outcome irrespective of the injury type.
Midterm Comparison of Tibial Fixation between Posterior Cruciate-Retaining and Substituting Porous Tantalum Total Knee Arthroplasty: Three-Dimensional Computed Tomography Analysis
Authors: Kaneko Takao , Kono Norihiko , Mochizuki Yuta , Hada Masaru , Toyoda Shinya , Ikegami Hiroyasu , Musha Yoshiro
Published: July 2019

Porous tantalum tibial component is durable with excellent bone ingrowth, higher knee scores, and long-term survivorship. However, to our knowledge, the effect of posterior cruciate-retaining (CR) and posterior cruciate-substituting (PS) porous tantalum tibial component has not been reported. The aim of the current study was to investigate the prosthetic bone quality between CR porous tantalum tibial component and PS using three-dimensional multi-detector-row computed tomography (3D-MDCT). Porous twenty-two (22) CR total knee arthroplasties and 22 PS received 3D-MDCT at every 6 months up to 5.5 years postoperatively to assess prosthetic bone quality (bone marrow contents/tissue volumes [BMC/TV, mg/cm3]) underneath the pegs of porous tantalum modular tibial component. Clinical outcomes (Knee Society score [KSS], Western Ontario and McMaster Universities (WOMAC), FJS-12, Patella score) were evaluated at a minimum follow-up period of 5.5 years. No statistically significant differences were found in age, gender, body mass index, KSS, and BMC/TV volumes in the proximal tibia between the two groups before total knee arthroplasty (TKA). There were also no significant differences between the CR and PS groups with regard to BMC/TV at every 6 months up to 5.5 years after TKA. At 5.5 years postoperatively, there was no significant difference between the two groups in terms of the KSS, WOMAC, forgotten joint score (FJS-12), and Patella score. The present study revealed that the prosthetic bone quality of the CR porous tantalum tibial component and PS were equivalent at every 6 months up to 5.5 years after TKA. This study reflects level II evidence.
The validity of high pressure IR for detecting the interactions between β-cyclodextrin and imidazolium based ionic liquids
Authors: Wang Teng-Hui , Hong Siang-Yun , Chang Hai-Chou
Published: July 2019

The effects of alkyl side-chain length on the interactions between imidazolium ionic liquids (ILs) and β-cyclodextrin (β-CD) were studied at ambient pressure and up to 2.5GPa. No noticeable changes in the C-H band frequencies of 1-methyl-3-propylimidazolium hexafluorophosphate ([MPIM][PF6]) were observed upon β-CD addition under ambient pressure. Nevertheless, β-CD addition inhibited the formation of the [MPIM][PF6] aggregated structure under pressures of ≤0.7 GPa. As the pressure was raised to 1.1–2.5 GPa, [MPIM][PF6] aggregated and formed self-associated configurations. This pressure-induced dissociation was not detected in the 1-butyl-3-methylimidazolium hexafluorophosphate and β-CD mixture ([BMIM][PF6]-β-CD) due to the long side chain in the [BMIM] cation. This indicates that the alkyl side-chain length of the imidazolium ILs plays a non-negligible role in controlling the order and strength of IL-β-CD interactions. It is well known that the validity of infrared spectroscopy for detecting the inclusion complexation is questionable in the literature. However, this study demonstrates that the combination of high pressure and IR spectroscopy may provide a suitable way to monitor the IL-β-CD interactions.
Assessing micrometastases as a target for nanoparticles using 3D microscopy and machine learning
Authors: Kingston Benjamin R. , Syed Abdullah Muhammad , Ngai Jessica , Sindhwani Shrey , Chan Warren C. W.
Published: July 2019

Metastasis of solid tumors is a key determinant of cancer patient survival. Targeting micrometastases using nanoparticles could offer a way to stop metastatic tumor growth before it causes excessive patient morbidity. However, nanoparticle delivery to micrometastases is difficult to investigate because micrometastases are small in size and lie deep within tissues. Here, we developed an imaging and image analysis workflow to analyze nanoparticle–cell interactions in metastatic tumors. This technique combines tissue clearing and 3D microscopy with machine learning-based image analysis to assess the physiology of micrometastases with single-cell resolution and quantify the delivery of nanoparticles within them. We show that nanoparticles access a higher proportion of cells in micrometastases (50% nanoparticle-positive cells) compared with primary tumors (17% nanoparticle-positive cells) because they reside close to blood vessels and require a small diffusion distance to reach all tumor cells. Furthermore, the high-throughput nature of our image analysis workflow allowed us to profile the physiology and nanoparticle delivery of 1,301 micrometastases. This enabled us to use machine learning-based modeling to predict nanoparticle delivery to individual micrometastases based on their physiology. Our imaging method allows researchers to measure nanoparticle delivery to micrometastases and highlights an opportunity to target micrometastases with nanoparticles. The development of models to predict nanoparticle delivery based on micrometastasis physiology could enable personalized treatments based on the specific physiology of a patient’s micrometastases.
Telecom wavelength single photon sources
Authors: Cao Xin , Zopf Michael , Ding Fei
Published: July 2019

Single photon sources are key components for quantum technologies such as quantum communication, computing and metrology. A key challenge towards the realization of global quantum networks are transmission losses in optical fibers. Therefore, single photon sources are required to emit at the low-loss telecom wavelength bands. However, an ideal telecom wavelength single photon source has yet to be discovered. Here, we review the recent progress in realizing such sources. We start with single photon emission based on atomic ensembles and spontaneous parametric down conversion, and then focus on solid-state emitters including semiconductor quantum dots, defects in silicon carbide and carbon nanotubes. In conclusion, some state-of-the-art applications are highlighted.
Preparation and properties of silane-treated banana fiber/poly(lactic acid) biocomposites
Authors: Insung T , Chaiyut N , Ksapabutr B , Panapoy M
Published: July 2019

Poly(lactic acid) (PLA) reinforced with silane-treated banana fiber (BFSi) at various fiber contents was studied. Banana fiber surfaces were firstly treated by sodium hydroxide and subsequently by 3-aminopropyl triethoxysilane. The biocomposites were then prepared by melt blending method in a twin-screw extruder. The effect of BFSi fiber contents on the mechanical and thermal properties of the biocomposites were investigated. Scanning electron microscope (SEM) was used to reveal the cryo-fractured surfaces of the composites. Mechanical properties, thermal characteristics and thermal stability were carried out by universal testing machine, differential scanning calorimeter (DSC) and thermogravimetric analyzer (TGA), respectively. Interfacial adhesion between PLA matrix and BFSi fibers was significantly improved even fiber content up to 40% by weight. There were few fiber pull-outs or voids appeared. With increasing fiber contents, tensile modulus and strength increased while elongation at break decreased. Moreover, glass transition temperature (Tg) and cold crystallization temperature (Tcc) decreased, whereas, crystallinity (Xc) significantly increased, however, melting temperature (Tm) was almost intact when fiber contents increased. The composites with higher amount of fibers exhibited faster thermal decomposition and higher residue contents at 550°C.
Mechanical properties of SiC fibers irradiated by swift heavy ions
Authors: Zhang L Q , Zhang C H , Huang Q , Yan T X , Ding Z N , Zhang X L , Chen Y G , Ma B S , Li J Y
Published: July 2019

Mechanical properties and surface features of SiC fibers irradiated with 246.8-MeV Ar ions at different fluences (1.5x1014, 9.0x1014, 1.8x1015, and 2.7x1015 ions/cm2) were investigated using a specific single filament tensile test and a field emission scanning electron microscopy (FE-SEM). Results reveal that carbon concentration on the fiber surface decreases while silicon concentration increases, with increasing ion fluence, accompanied by an adsorption of oxygen. Meanwhile, the diameter of fibers first reduces and then increases, with increasing ion fluence. Moreover, at 2.7x1015 Ar ions/cm2 irradiation, some fibers were fractured. As a result, the mean tensile strength and the average elastic modulus of fibers decrease generally with respect to the ion fluence. The degradation mechanisms of mechanical properties of SiC fibers under irradiation were discussed in detail.