bluuebunny/crossref_metadata_2025 huggingface dataset:
Application of wavelet analysis of X-Ray computed tomography histogram for phase segmentation
Authors: Kadyrov R , Starovoytov A , Utemov E
Published: June 2020

With the development of unconventional resources, the standard task of evaluation the porosity and oil saturation needs a new approach. Heavy oil and bitumen can act as the cement in many sand reservoirs, which excludes the use of standard measuring techniques. A method for phase segmentation and estimating the porosity and oil saturation of heavy oil reservoirs, based on wavelet analysis of X-ray computed tomography histogram was proposed. Its advantages are reducing human influence on phase thresholding and the ability to work with loose sand reservoirs, for which it is not possible to use standard assessment methods. The main problem found for this method is the need for high detailing of segmentation objects since a large amount of noise and transition voxels adversely affect class recognition and quantitative interpretation. The application of wavelet analysis approach for naturally heavy oil saturated samples requires high-resolution microCT (less than 5 µm) and high oil saturation of the samples.
Comparative mineralogy and petrography of the basalts of Vesuvius and Batur volcanoes
Authors: Kadyrov R , Minibaeva E
Published: June 2020

In areas of active volcanic activity, sedimentary rocks can form both directly during eruptions and the destruction of effusive rocks. Therefore, the study of effusive parent rocks such as basalts is very important. This work provides information about the history of formation and geological structure of Vesuvius and Batur volcanoes, which are located at different ends of the Mediterranean-Alpine-Himalayan folded belt and have a similar layer-cone structure and they are represented by alkaline (subalkaline) type of magmas. Based on the research and literature data, it is found that modern basaltic samples from these volcanoes are mineralogically close. The basalt of Mount Batur was formed from lavas with higher aluminium content in the melt, higher viscosity, with strong degassing and rapid cooling. The formation of effusive rocks of Vesuvius, on the contrary, is associated with a lower viscosity of lava, a lower content of aluminium and its slower cooling. They underwent more significant secondary changes.
Paleogeographic causes of the formation of mineral deposits on the east of the East European platform in the Permian period
Authors: Khasanov R , Balabanov Yu
Published: June 2020

There took place cardinal paleo- and zoogeographic changes in the second half of the Permian period and the beginning of the Triassic on the east of the East European Platform. These changes have been reflected in the geochemical features and magnetic properties of the rocks, the isotopic composition of chemical elements, the characteristics of the fauna, as well as the nature of the sediments. Permian sediments complete have an extremely complex geological structure, are characterized by a diversity of lithologic-facies composition and occurring of specific minerals, which are considered indicators of various types of lithogenesis (sulfate-carbonate rocks, coals, copper sandstones, schists, etc.). Based on lithological and paleomagnetic studies, paleogeographic reconstructions were performed. They showed that one of the factors of Perm sedimentation and related processes of the formation of ore and nonmetallic minerals are global climatic changes caused by Carboniferous-Permian glaciation.
Dispersed organic matter in the rocks of fluid seals according to magnetic radiospectroscopy
Authors: Khasanova N M , Izotov V G , Sitdikova L M , Zakharchenko A L , Sidorova E U , Khasanov R A , Nizamutdinov N M
Published: June 2020

The purpose of this work is to use methods of magnetic radiospectroscopy – electron paramagnetic resonance (EPR) and low-field nuclear magnetic resonance (NMR LF) to determine the quality of the rocks of fluid seals of “lingul clays” (depth 82-102 m) of the Ashalchinskoye field, combining traditional methods of studying the properties of the material composition of rocks and dispersed organic matter in them. The heterogeneity of the mineral composition by the distribution of the EPR signal intensity of the ion Mn2+ has been established; it is mostly dense carbonate in the upper part, below it passes into the magnesian calcareous and ends with the clay part. Mineral heterogeneity is consistent with an increase in pore space in the middle and lower parts of the section. The EPR spectra of impurity ions in the structure of carbonate minerals, impurity ions Fe3+ in the structure of silicon compounds and the E’-center line in quartz control the state of the rock mineral matrix. The EPR signal of free radicals Corg characterizes the presence of organic matter. The presence of an insoluble part of organic matter, or the ability to generate hydrocarbons, is recorded by the newly formed radical C350 after

isothermal annealing of the rock at a temperature of 350°C.
Geochemical variations in the Upper Kazanian (Middle Permian) stratotype section, Russia
Authors: Nurgalieva NG , Gareev BI , Batalin GA
Published: June 2020

The present paper shows elemental and carbon and strontium isotope composition of the Upper Kazanian (Middle Permian) stratotype section Pechishchi, Russia. A new version of Noinsky’s cycles scheme has been obtained for Martinet and Sougy’s Diagram types of carbonates, with the geochemical indices values changing within marine, evaporate and clastic beds. The δ13Ccarb values vary within interval 0 − +10‰ V-PDB with a mean value 6.2 ‰ V-PDB. The negative excursions of δ13Ccarb values (with amplitudes 2-8 ‰) are assigned as significant land-derived sedimentary inputs. The values of 87Sr/86Sr ratio in the data set of 17 samples change from 0.707267 to 0.707417 (mean value 0. 70734). On standard 87Sr/86Sr curve these values correspond to the interval 273 – 268 Ma.
Geochemical features of pyrite pseudomorphs according to plant residues from the Upper Jurassic deposits of the Middle Volga river area (Russian Federation)
Authors: Shilovsky O , Khasanov R
Published: June 2020

The study of the mineralogy and geochemistry of biomorphic ore formations has great importance for studying the processes of transformation of plant tissues during the formation of the sedimentary rocks, including ore mineralization. Forms of biogenic mineralization in sedimentary rocks are represented by various processes. The pyritization of organic residues is one of the most common forms. The purpose of this work was to conduct a detailed mineralogical and geochemical study of biomorphic ore formations collected from Mesozoic (Upper Jurassic) deposits of the right bank of the Volga river. The initial conditions for the fossilization of the objects of study were the same. Therefore, the structural and morphological features of the pyrite aggregate developing on them can be caused not only by geochemical conditions but also by the structure of the residues themselves. Samples were examined by optical microscopy, X-ray phase analysis, gamma-ray spectrometric analysis, X-ray computed tomography and X-ray fluorescence analysis. As a result of research, the stages of mineralization of wood were established, which reflect the features of sedimentation.
Microstructure and geochemical features of hard dental tissues of Deltavjatia vjatkensis and Suminia getmanovi Permian tetrapods (Kotelnich site, Kirov region, Russia)
Authors: Shilovsky O , Kiseleva D
Published: June 2020

The Kotelnich pareiasaur site, one of the richest of the Permian period, is characterized by the unique integrity of fossil vertebrate assemblages and the preservation of bones’ internal structure (including fossil cellular structures) due to their burial features. Pareiasaur and suminia are two most widespread and most frequently encountered representatives of fossil fauna at the Kotelnich site, belonging to the herbivorous form of trophic affiliation. In the present work, a high degree of the structural preservation of the hard dental tissues of pareiasaur and suminia is demonstrated using scanning electron microscopy and energy dispersive X-ray spectroscopy. Fluorapatite composition of tooth tissues is indicated with trace rare earth elements and uranium incorporated from the host rock as a result of diagenetic alteration during fossilization. No secondary mineralization has been found in the pulp chamber uncovered by a cleavage. The features of its primary internal structure are observed such as pseudomorphs of iron-containing minerals over the fibrils of collagen fibers connecting odontoblastic processes with the walls of dentin tubules, as well as spherical pseudomorphs over blood-like cells.
New data on the composition of organic matter of deep-seated rocks of Bashkortostan by NMR in a low magnetic field
Authors: Sitdikova L M , Khasanova N M , Korepanov E S , Sakharov B V , Volkov V Ya , Lozin E V
Published: June 2020

The study of the organic matter of Riphean-Vendian deposits, the features of its distribution are the subject of research by many authors. The problem of hydrocarbon of these deposits remains relevant. We have conducted studies of deep-seated rocks of the Lower Riphean of the kaltasinskaya suite of the Eastern-Askinskaya area, with an increased content of organic matter in individual intervals. In addition to standard research methods, the method of nuclear magnetic relaxation in a low magnetic field was used. This method allows determining the phase state of organic matter in the original rock without any impact and after isothermal heating of the rock at 350°C. The free induction signal and the type of solid-phase signal, which corresponds to the waveform for the asphaltene component of the oil, were analyzed. The predominant part of the liquid-phase signal - about 35%, is characterized by a transverse relaxation time of 540 ¼s, corresponding to the resinous component of organic matter. The quantitative ratio of asphaltenes before and after heat treatment was also analyzed. A significant decrease in its amount was recorded. During thermal exposure, more than 55% of light, more mobile hydrocarbon molecules are formed in the liquid-phase part of organic matter.
Phase state of an organic matter for NMR relaxation in low fields of rocks of the Bazhenov suite (Western Siberia)
Authors: Sitdikova L M , Khasanova N M , Bondarev E V , Sakharov B V , Volkov V Ya , Sidorova E U
Published: June 2020

The work of many researchers is devoted to studying the problem of the features of the formation of the Bazhenov suite and organic matter. Various methods are used to study the type and state of organic matter, despite this, the problem associated with the phase state and type of organic matter in these deposits, the methods for studying those remains relevant. One of these methods is the NMR relaxation method in low fields. For the analysis of heavy oils, the method of simultaneous measurement of the free induction decay (FID) together with the decay of the echo signal in the Carr-Purcell-Meiboom-Gill (CPMG) pulse program was used. We studied the decay form of relaxation curves and their approximation by a mathematical model adequate for solid, liquid, and gaseous states of matter, which contains information on the geochemical and petrophysical properties of organic matter, as part of a single reservoir, including both the mineral part and the fluid part.
Aquathermolysis of heavy oil in the presence of iron tallate and mineral components of reservoir rock
Authors: Khashan G , Sitnov S , Ziganshina M , Dolgikh S , Slavkina O , Shchekoldin K
Published: June 2020

This study is devoted to conversion of heavy oil in sandstone, taken from the Ashalchinskoye field in Tatarstan, Russian Federation, in the presence of an oil-soluble catalyst precursor based on a transition metal of iron in water vapor. The mass content of a portion of the catalyst, in a hydrogen donor based solution totals 2.0 wt % of the oil extract in the rock sample. It was found that according to the results of the chemical composition study, the introduction of the catalyst ensures the conversion of resins (by 24 wt %) at 250°C and a significant conversion of asphaltenes at 300°C, the content of which decreases practically to “trace” amounts at this temperature. The intensification of the destructive processes of breaking heteroatom bonds in the molecules of resins and asphaltenes contributes to the generation of light liquid hydrocarbons.
Conversion of heavy crude oil with carbonate rock in the medium of water superheated steam
Authors: Nasyrova Z , Aliev A , Affane B , Popkov A , Proshchekalnikov D , Bashkirtseva N
Published: June 2020

A series of experiments with heavy crude oil were carried out by modeling hydrothermal effects involving mineral compounds of carbonate rocks. Depending on the thermodynamic parameters of exposure, various mechanisms of chemical transformations of heavy crude hydrocarbons predominate, affecting its composition and properties. In this paper, samples of crude and converted oil were analyzed by various instrumental methods. The work on the aquathermolysis of oil was carried out in a laboratory batch unit under isothermal conditions at of 290-375°C and pressures of 1-13.5 MPa. In this work, component composition, chromatographic analysis, rheology, X-ray analysis of heavy crude and converted oil were carried out. In converted crude oil the content of light fractions boiling up to 200°C increased with increasing in the specific surface of mineral compounds under hydrothermal influence. The results of X-ray structural analysis showed the presence of chemisorption processes on the surface of mineral particles as a result of hydrothermal influence on crude oil.
Influence of metal oxides and their precursors on the composition of final products of aquathermolysis crude oil
Authors: Ivanova I , Kutlizamaev R , Safin B , Grishko A , Sitnov S , Slavkina O , Shchekoldin K
Published: June 2020

Experiments were conducted simulating the hydrothermal effect on heavy oil in the presence of carbonate, kaolin, Al2O3, Ni+2 and Cu+2, NiO mixed with poly-α-olefins, C6H8O7, C2H4O2 at temperatures of 290-375°C and pressures from 1,0 to 13.5 MPa. As a result of the research, a decrease in the viscosity of the organic end products of hydrothermal exposure due to the redistribution of n-alkanes in the direction of the formation of low-molecular homologs was established. This led to an increase in the content of saturated hydrocarbons and light fractions in the final products of the conducted studies. Under hydrothermal conditions of heavy oil conversion, products of the reactions of destruction of the results of the research can be applied in the development of new innovative technologies for the development of unconventional hydrocarbon resources.
Mixed oxide Zn-Fe with magnetic properties as a catalytic system for the aquathermolysis of heavy oil
Authors: Lakhova A , Zakieva R , Valieva A , Vasiliev Ed , Bashkirtseva N , Petrov S
Published: June 2020

This article investigates the catalytic and magnetic abilities of mixed Zn-Fe oxides during aquathermolysis of heavy highly viscous oil. These systems influenced both the composition of the oil transformed during aquermolysis and its viscosity, moreover, the oil transformed using a Zn-Fe-MO sample (1:1) has a more flatter viscosity-temperature dependence. During magnetic manipulations, it was proved that a mixed Zn-Fe oxide with a ratio of Zn2+/Fe3+ = 2 cations in the synthesis of layered double hydroxide precursors shows better magnetization (the degree of extraction from the reaction was 91 wt %) and it can be removed from the reaction mixture.
Refining super-viscous oil in supercritical aqueous fluid
Authors: Zakieva R , Petrov S , Lakhova A , Bashkirtseva N
Published: June 2020

A comparative analysis of products of hydrothermal transformation of super-viscous oil above the critical point of water at elevated temperatures of 375-385°C and pressures of 22-23 MPa in the presence of coal and oxides of iron, aluminum, copper and nickel was carried out. The regularities of changes in the structural-group and component composition, as well as the physicochemical properties of aquathermolysis products of super-viscous oil of B2 type of Ashalchinskoye field, were established. It was shown that destruction of high molecular weight components of super-viscous oil under conditions of its watermolysis in the presence of manganese and iron oxides lead to the formation of low-boiling hydrocarbon fractions. The predominant course of the destruction of resinous components, aliphatic substituents of asphaltenes and branched aliphatic structures with the redistribution of alkanes of normal structure towards their low molecular weight homologs has been established.
Structure of nanostructured layered double hydroxides according to x-ray diffraction analysis data
Authors: Popkov A , Gabdrakhimova E , Sharafieva Z , Isakov D
Published: June 2020

Nowadays, in many areas of industry, in particular, the petrochemical industry, the problem of multifunctional, efficient and environmentally friendly materials use is of great importance. One such material is double layered hydroxides (LDHs) used in various synthesis reactions, catalytic and adsorption processes. This paper presents studies on the effect of the elemental composition of LDH on their structure. Under experimental conditions, 4 samples of LDHs based on Mg and Al, Mg and Fe, Zn and Al (2 samples with different cation ratios) were synthesized by co-precipitation of a base solution with a mixture of M(II) and M(III) salts solution. The phase composition of the obtained LDHs were analyzed by powder x-ray diffraction method. During the experiment, the characteristics of the Zn-Al LDH samples turned out to be lower than MgFe and MgAl LDHs due to the presence of a phase of zinc oxides in their composition, as well as the structure of the obtained products. Similarly, the size of ZnAl crystallites of LDH at a trivalent cations share of 0.33 compared to 0.4 was larger by about 3.5 times.
The influence of the ARPD composition on the heat of dissolution in hydrocarbon solvents
Authors: Ibragimova D , Sharafieva Z , Sharifullin A , Chinedu U , Isakov D , Kamara M
Published: June 2020

In this paper, we studied two samples of asphlatene-resin-paraffin deposits of different composition, precipitated during the extraction of hard-to-recover oil and characterized by different melting points. The samples were studied by the thermal analysis method on the MOM (Hungary) Q-1500D derivatograph. The compositions of samples were studied by SARA-analysis by taking into account the methodical recommendations of ASTM D4124-09 and GOST 32269-201. The process of asphlatene-resin-paraffin deposits dissolving in straight-run fractions was studied. Straight-run fractions 80-180°C and 180-350°C were used for heat dissolution experiments. The heat of dissolution of asphlatene-resin-paraffin deposits in fractions was measured on a calorimeter. The graphs that indicate the dependence of the heat of dissolution of asphlatene-resin-paraffin deposits on its concentration in fractions were plotted. The efficiency of the dissolution process was determined.
The separation of heavy crude oil by spray evaporation
Authors: Petrov S , Lakhova A , Safiulina A , Fakhrutdinov R , Bashkirtseva N
Published: June 2020

Studies have shown a significant intensification of the process of flash evaporation by spraying heavy oil through a nozzle. By changing the temperature in the apparatus and the pressure gradient, the carryover of the liquid phase by the distillate was set within the required limits. Results on flash evaporation of heavy crude oil at 200, 250, 300 and 350°C without spraying and with spraying through nozzles showed a significant intensification of the process with an increase in the yield of the distillate product from 22 to 67 wt %. Upon reaching a moderate degree of entrainment of 6 wt % with an increase in the yield of distillate to 43 wt % at 300°C, the viscosity of the distillate at 20°C does not exceed 15 sSt, density 0.8199 g/cm3, sulfur content no more than 2 wt %. Intensive flash evaporation process can be successfully used for the primary refinement of heavy high-viscosity oils. As a result of the process, two products from heavy oil are produced: high-quality light distillate, enriched in fuel fractions, and the residue, which can serve as raw material for the bitumen production.
Production of Liquid Bio-Fertilizer from Old Coconut Water and Molasses using Consortium Microbes
Authors: Darmawan R , Dewi V G P , Rizaldi M A , Juliastuti S R , Gunawan S , Aparamarta H W , Wiguno A
Published: June 2020

Increasing issue of returning to nature, the presence of organic fertilizer is one of the things required in agriculture sector. The presence of the liquid organic fertilizer, it is expected to have a positive impact on plants and soil. Moreover, in the manufacturing process, it was utilizing wastes. The liquid fertilizer was made by mixing waste from micro-businesses that produce a porridge (old coconut water) and side product of the sugar factory (molasses). Seven litter solutions from the liquid were mixed using a bioreactor equipped with impeller for 8 incubation days. The isolated microbes were inserted with initial number of 1012 using counting chamber method. As a phosphate source, the phosphate rock was implemented into reactor. Every 4 days, the samples were taken and analysed for knowing the concentration of NPK and C components. Three consortium microbe variables were carried out for making the fertilizer where the source of microorganisms from enrichment cultures + old coconut water + molasses (EOM); soil + old coconut water + molasses (SOM); and only old coconut water + molasses (OM). The highest (%) of N, P, K and C components was detected at 0.09; 0.04; 10.5 and 1.74, respectively achieved by the EOM after 8 day of incubation period. The bio-fertilizer was applied into the paddy test plants with a hydroponic system.
Effect of operating conditions on the efficiency of adsorption of Manganese (Mn) metals using Nano Zeolite adsorbents
Authors: Syamsuddin Y , Zulfikar  , Meirisa F , Muchtar S , Ambarita A , Mulyati S , Suraiya  , Rosnelly C M , Arahman N
Published: June 2020

Manganese (Mn) is one of the most abundant metal in the soil. The presence of this metal is essentially needed by living things for the formation of cartilage and bone as well as driving various enzymes. However, in excessive amounts, the metal can cause disruption of the central nervous system. In this study, the removal of Mn was carried out by the adsorption process using zeolite adsorbent. Effects of contact time, pH of sample (2, 3, 4, 5, 6, 7, 8, and 9) and dosage of adsorbent (1; 1,5; 2; 2,5; 3; 3,5; 4; 4,5 and 5 g) were evaluated. The optimal conditions were obtained under operating conditions of 100 minutes contact time, 7 and 9 pH of the sample, and 5 g dosage of adsorbent. The adsorption process was able to reduce Mn metal up to 79.52%. The initial concentration of Mn sample was 5 g/L and the concentration of effluent after the adsorption process reduced to 1,024 g/L. The adsorption process resulted in a significant reduction of Mn level. However, the final result of the process shows the level of Mn that still exceeds the limit permitted by KEPMENKES No. 907/MENKES/SK/VII/2002 of 0.1 mg/L.
Waste Peel of Durian as Solid Cataysts for Biodiesel Production
Authors: Fitriani F , Husin H , Marwan M , Nasution F , Zuhra Z , Asnawi T M , Hisbullah H
Published: June 2020

In this study, peel durian ash was used as a solid catalyst to convert rubber seed oil into biodiesel production via transesterification reaction. The catalyst was fabricated by simple burning and calcined at 600°C for 8 h. The morphology of particles was confirmed by Scanning Electron Microscopy (SEM). The Energy-dispersive X-ray Analysis (EDX) was used to obtain the atomic composition and percentage of the catalyst. The reaction was carried out at 65°C for 1 h. Whereas, the catalyst loading were varied of 1.0%, 2.5%, 5.0%, 10% and 15% wt.%. From EDX data was confirmed that the ash catalyst composes of the potassium oxide (K2O) as the dominant compound. The performance of the catalyst was evaluated from a transesterification reaction for biodiesel production. The highest biodiesel yield of 96.5% was obtained in the reaction using a catalyst of 10 wt.%. The density obtained was 0.865 gr/cm3confirming the produced biodiesel complies with the SNI standard.
The effect of pH on Synthesis of ZnO-Natural Zeolite Nanocomposite by Co-Precipitation Method
Authors: Agustina T E , Prajawita A U , Sinaga S A S
Published: June 2020

Currently, the method being developed to overcome environmental pollution generated by synthetic dyes produced from the textile industry wastewater is by photocatalysis using photocatalyst materials. Photocatalysis is a relatively inexpensive and easy method to implement. Photocatalysts that have received major attention and widely studied are metal oxide semiconductors such as ZnO. Photocatalyst activity can be increased through the development of supporting materials such as zeolites. This study aims to synthesize ZnO-natural zeolite photocatalysts nanocomposite by co-precipitation method in order to take advantage of the adsorbent and catalyst properties in the natural zeolites and the photocatalyst properties in the ZnO. To study the effect of pH, ZnO-natural zeolite nanocomposites are synthesized with different pH under alkaline conditions (pH of 8-11). Nanocomposite materials obtained then tested its photocatalyst activity in degrading of 50 ppm procion red synthetic dyes. The ZnO-natural zeolite nanocomposites produced were characterized by using XRD, SEM, and BET. The synthesized ZnO-natural zeolite nanocomposite showed the best results at pH of 10, with the ZnO crystallite size of 20.99 nm, the surface area of 134.35 m2/g, and the Zn contained of 10.05%. Procion red degradation of 75.54% was attained by using ZnO-natural zeolite nanocomposite photocatalyst after 120 minutes of UV irradiation.
Optimization of series-parallel connection of PV array to mitigate negative influence of partial shading conditions
Authors: Kurmanbay A , Baktybekov K , Sakhanov K , Syzdykov A , Mukhamediyev A
Published: June 2020

Rapid development in the photovoltaic systems demanding more and more efficient solutions, not only in micro-fabrication techniques but in energy extraction methods as well. In recent decades large number of Maximum Power Point Tracking algorithms with different complexity accompanied by the capability to efficiently locate global maximum under partial shading were developed. However, a deeper look at the problem reveals that to further enhance the performance of the PV system under non-uniform irradiance there is a need for hardware intervention to the interconnect, or in other words adjustments to the panel configuration. In this paper, we propose a simple technique for optimizing the electrical scheme of the solar panel (connection of individual cells) by using a simple algorithm which disperses shadow across all structure. The method allows to mitigate partial shading effect on solar panels of any size and shape, therefore rise efficiency of energy extraction. Thus static optimization of the PV panel configuration disperses partial shading across all structure and ensures more synchronous functioning of the PV cells. The resulting structure not only capable of extracting more available power but, straighten ups power curve to loosen requirements for MPPT computations.
A method of joint high-precision estimation of range and velocity in a radar using ultra-wideband frequency coded waveforms
Authors: Sapronov D , Kamenskiy I , Kirdyashkin V
Published: June 2020

The article describes a method of joint high-precision estimation of range and velocity in ultra-wideband short-range radar systems. The peculiarity of the method is the two dimensional range-velocity compression function based on ambiguity function of ultra-wideband discrete frequency coded waveforms. Expressions of ambiguity function and compression function such as a block diagram of the radar transceiver for the proposed method are presented. Experimental data confirm the efficiency of the method.
Architecture of air conditioning system with electric-motor-driven blowers
Authors: Gubernatorov K , Kiselev M , Moroshkin Y , Chekin A
Published: June 2020

Architectures for air conditioning systems based on electrically driven air pumps for perspective commercial aircraft with a high level of electrification are very diverse. To select the optimal structure of such air conditioning systems for a specific aircraft and to create a scientific and technical groundwork for systems of this type for a wide class of commercial aviation aircraft this article proposes a combinatorial-logic method for design architecture of air conditioning system with electric blowers. The method is based on an oriented graph of combinations of subsystems and units with an assessment the quality of each variant in terms of aircraft fuel efficiency. The method allows to design a concept of on-board equipment in order to create an aircraft with a high level of electrification and to form a knowledge base on air conditioning systems with electric blowers, as well as a hybrid air conditioning systems where electric blowers are combined with other sources of fresh air to supply the aircraft’s pressurized cabin.
Influence of the discharge circuit inductance on the ablative pulsed plasma thruster performance
Authors: Diakonov G A , Lyubinskaya N V , Semenikhin S A
Published: June 2020

The most promising option for motion control of small spacecrafts with weight less than 50 kg is a pulsed plasma thruster with an energy of less than 20 J (micro-PPT), which has such advantages as low weight, structure simplicity, precise pulse control, sufficiently long life time, constant operational readiness and low inertia. It was believed that PPT with low discharge energy (less than 20 J) needed reduction of the initial inductance, despite the fact that the low capacity of the capacitor bank would not allow to achieve the optimal C/Lo ratio. However, the results of calculations and experiments show that a slight increase in the initial inductance of the discharge circuit, contrary to the assumptions, has a positive effect on the micro-PPT characteristics, reducing the propellant consumption and mainly increasing the specific impulse without significant reduction of the thrust impulse (unit impulse). This feature of the discharge circuit of the PPT with a low discharge energy allows us to discover new solutions in micro-PPT designing and improve the thruster specific characteristics.
Comparative analysis of calibration variants for inertial measurement unit based on microelectromechanical system
Authors: Krylov A A , Veremeenko K K
Published: June 2020

This paper is about comparison of two methods of calibration – calibration method for inertial measurement unit with gyroscope and accelerometer direct information outputs and calibration method for strapdown inertial navigation system with coordinate, velocity and orientation outputs. Two mathematical methods - Least Squares and Kalman Filter methods are applied respectively. Both methods assume the same mathematical error model. This model includes zero drift, nonlinearity coefficients, nonorthogonal projections and also noises of these parameters The research compare these methods and make attempt to give approximate numerical results. The results reveal features of each case, e.g. optimal calibration time for Kalman Filter and opportunity to find unknown noise parameters in inertial measurement unit variant. These features can help a researcher to choose a suitable variant, all else being equal it is recommended to use the inertial measurement unit variant.
Consideration of aeroservoelasticity requirements in the development of highly maneuverable unmanned aerial vehicle
Authors: Parafes’ S , Turkin I
Published: June 2020

An approach to the joint design construction and stabilization system of the highly maneuverable unmanned aerial vehicle account with requirements of aeroservoelacticity, the most important of which is to prevent self-oscillations in the unmanned aerial vehicle stabilization loop. The approach includes three stages. The first stage is the preliminary choice of structure and basic parameters of the unmanned aerial vehicle stabilization loop account with aeroservoelacticity requirements. The second stage is the separate design of subsystems (airframe, stabilization system) by traditional methods in compliance with the requirements formulated at the first stage. The goals to be achieved at this stage are to obtain a rational (from the standpoint of mass and technological perfection) design of the unmanned aerial vehicle airframe, and a stabilization system that provides the required dynamics and the accuracy of execution of commands, as well as the minimum cost, dimensions and weight. The third stage is the coordination of the selected structure and design parameters of the airframe and stabilization system, aimed at meeting the aeroservoelasticity requirements (the authors use the model of the unmanned aerial vehicle stabilization loop stability study, reflecting the specifics of the classes of highly maneuverable aircraft). An example of the process of developing the highly maneuverable unmanned aerial vehicle account with aeroservoelacticity requirements is given.
A parametric analysis of the output voltage of all-vanadium redox-flow battery system
Authors: Al-Yasiri M A
Published: June 2020

Vanadium redox flow battery (VRFB) becomes a global technology used in stationary applications like grid storage. The characteristics of output voltage during the charge-discharge cycles and the resulted power of VRFB are strongly based on solving a multidisciplinary problem. In this paper, a 2 D steady state numerical model for the operation of a single VRFB has been formulated, validated with good agreement, and tested. The output voltage response of VRFB at different state of charges (SOCs) has been investigated under range of volumetric flow rates and current densities. Next, a comprehensive parametric analysis, sensitivity study, for the major electrode and electrolyte material properties is conducted which can improve confidence in model predictions. The results showed that increasing flow rate can help to minimize concentration polarization, however, pumping power would be dominated. A low flow rate can cause some poor covered regions, but would reduce pumping power. Based on the sensitivity results, only cathode reaction rate, specific surface area, conductivity of porous electrode and electrolyte, and carbon felt porosity are input parameters that dominate the simulation results. It is expected that this proposed model would be applicable to most flow batteries architectures and can be extended to stack flow batteries.
Identifying the nutritional composition of fish waste, bones, scales, and fins
Authors: Maktoof Afrah A. , Elherarlla Roaa Jafar , Ethaib Saleem
Published: June 2020

Extraction valuable products from fish waste such as protein, lipid has gained more research attention around the worldwide. In this study, a fish waste was subjected to approximate analysis to determine the nutritional composition includes protein, lipid, and carbohydrates as well as moisture and ash content. The fish waste included scales, fins, and bones isolated from Cyprinus carpi fish samples. The fish samples were divided into three samples groups and named G1, G2, and G3.The results showed high protein content in fish waste and the highest value 27.3 % found in bones (G3). The highest value of lipid content also was recorded in bones 7%. The higher moisture content was detected in scales parts 73% accompanied with a significant difference (P-value <0.05) in the scales moisture contents among the three fish waste groups. In addition the results revealed that the protein and lipid content increased with increasing weight and size of fish. In general, this study presents a high nutritional value of fish waste, providing another a viable source for sustainable food industry.
Photocatalytic removal of eosin dye from aqueous solution over titanium dioxide
Authors: Al-Gubury Hazim Y , Saad Suad T , Alrazzak Nour Abd , Naif Ruqaia M
Published: June 2020

A Various concentrations of Eosin dye were irradiated using titanium dioxide as a catalyst. The irradiation was carried out using the catalyst (0.1gm/100ml), mercury lamp 125 Watts from external source and at Rt. The effect of TiO2on the photocatalytic degradation of Eosin was studied in various conditions such as, studying the effect of loaded mass of titanium dioxide, effect of eosin dye concentration and effect of inorganic anions.
“Impact of culvature and magnetic force on waveform transition of Pseudo plastic fluid in flexible channel”
Authors: Alshareef T Sh
Published: June 2020

Waveform transport of Pseudo plastic fluid in complaint symmetric channel with culvature properties has designed. The efforts of magnetic force, which has applied by radiate direction in the analysis, is considered by using the influence of Hartmann number. Walls properties with slip conditions on velocity distribution as well as stream function are used. The analysis of" heat and mass transfer" has taken into account. More popularized factual constraints known by the convective conditions are applied. The partial differential equations of motion, temperature and concentration is reduced under the simulation of low quantity of wave number and Reynolds number and then transformed to ordinary differential equation of independent variable of radial coordinate (η). The result equations are solved by using homotopy analysis. Impacts of sundry variables on the axial velocity, trapped bolus, temperature and concentration has examined. It is found that velocity is a decrescent function for Hartmann number (Ha) and it‘s curve is not symmetric for small values of culvature and the case is opposite for large values of it. Also we found that the temperature is an growing function of Brinkman number while the concentration is a decreasing function of soret and Schmidt numbers. Influences of most variables are supported by graphs. The numerical and figures are obtained by using the software of Mathematica program.
On Bayesian Estimation of System Reliability in Stress – Strength Model Based on Generalized Inverse Rayleigh Distribution
Authors: Jebur Iman Ghaji , Kalaf Bayda Atiya , Salman Abbas N.
Published: June 2020

The parameter and system reliability in stress-strength model are estimated in this paper when the system contains several parallel components that have strengths subjects to common stress in case when the stress and strengths follow Generalized Inverse Rayleigh distribution by using different Bayesian estimation methods. Monte Carlo simulation introduced to compare among the proposal methods based on the Mean squared Error criteria.
Pu-visible Submodule with their most prominent characteristics
Authors: Al-Quraishi Abass D. , Shihab Buthyna N.
Published: June 2020

In this article, the concept of pu-visible submodules of an S-module Y is introduced which is a generalization of the concept of visible submodule. Some charactrizations and properties are proven. Also the results of pu-visible submodule by a module Y will by presented by giving many results and properties that explain and discuss that concept, one of the most important of them show that the submodule of Y is pu-visible when the residual of it is pu-visible ideal of S and the opposite is achieved. In addition to many results that have been presented.
Growth and Bounded Solution of Second-Order of Complex Differential Equations Through of Coefficient Function
Authors: Saleh Haneen Abbas , Alhily Shatha S.
Published: June 2020

The purpose of this research paper, is to present the second- order homogeneous complex differential equation f" + H(z)f = 0, which defined on the disk D = {z ∈ ℂ : |z − i| ≤ 1} ⊆ ℂ, where H(z) = e

p(z), to show it an invariant by applying Liouville and self-adjoint transformation with an examine the convexity property of its coefficient H(z) = e

p(z), in order to study the growing and bounded solution of consider equation.
Disruption and Compensation of Sulcation-based Covariance Networks in Neonatal Brain Growth after Perinatal Injury
Authors: Kim Sharon Y , Liu Mengting , Hong Seok-Jun , Toga Arthur W , Barkovich A James , Xu Duan , Kim Hosung
Published: June 2020

Perinatal brain injuries in preterm neonates are associated with alterations in structural neurodevelopment, leading to impaired cognition, motor coordination, and behavior. However, it remains unknown how such injuries affect postnatal cortical folding and structural covariance networks, which indicate functional parcellation and reciprocal brain connectivity. Studying 229 magnetic resonance scans from 158 preterm neonates (n = 158, mean age = 28.2), we found that severe injuries including intraventricular hemorrhage, periventricular leukomalacia, and ventriculomegaly lead to significantly reduced cortical folding and increased covariance (hyper-covariance) in only the early (<31 weeks) but not middle (31–35 weeks) or late stage (>35 weeks) of the third trimester. The aberrant hyper-covariance may drive acceleration of cortical folding as a compensatory mechanism to “catch-up” with normal development. By 40 weeks, preterm neonates with/without severe brain injuries exhibited no difference in cortical folding and covariance compared with healthy term neonates. However, graph theory-based analysis showed that even after recovery, severely injured brains exhibit a more segregated, less integrated, and overall inefficient network system with reduced integration strength in the dorsal attention, frontoparietal, limbic, and visual network systems. Ultimately, severe perinatal injuries cause network-level deviations that persist until the late stage of the third trimester and may contribute to neurofunctional impairment.
Chatbots
Authors: Lee Jang Ho , Yang Hyejin , Shin Dongkwang , Kim Heyoung
Published: June 2020

In this series, we explore technology-related themes and topics. This series aims to discuss and demystify what may be new areas for some readers and to consider their relevance for English language teachers.
P473Safety and efficacy of direct oral anticoagulants compared to vitamin K antagonists in patients with atrial fibrillation undergoing percutaneous coronary interventions: A meta-analysis
Authors: Agasthi P , Lee J Z , Pujari S H , Tseng A S , Shipman J , Almader-Douglas D , Ashraf H , Mookadam F , Fortuin F D , Beohar N , Arsanjani R , Mulpuru S K
Published: June 2020

Background

 Coronary artery disease (CAD) and atrial fibrillation (AF) are commonly associated. Co-treatment with multiple anti-thrombotic agents can increase the risk of bleeding.

Purpose

We sought to evaluate patient-centered outcomes in patients with AF on double therapy with direct oral anticoagulants (DOACs) compared to patients with standard triple therapy, [a vitamin K antagonist (VKA) plus dual antiplatelet therapy].

Methods

We performed an extensive systematic review of the literature and meta-analysis of randomized controlled trials reporting outcomes of patients receiving double therapy with DOACs compared to triple therapy with VKAs in patients with AF undergoing percutaneous coronary intervention (PCI). Patient-centered outcomes were the International Society of Thrombosis and Hemostasis (ISTH) major or clinically relevant non-major bleeding (CRNB), all-cause mortality, major adverse cardiovascular events (MACE), myocardial infarction, stent thrombosis, and stroke.

Results

Four randomized controlled trials (9602 patients) met our inclusion criteria. Compared to VKAs, DOACs were associated with significantly lower ISTH major bleeding/ CRNB (RR - 0.75, 95% CI: 0.67-0.82, p < 0.00001, I2 = 11%). There were no statistically significant differences in the efficacy outcomes, including myocardial infarction (RR- 0.99, 95% CI :0.79-1.25, p = 0.96, I2 = 0%), stent thrombosis (RR - 0.97, 95% CI: 0.6-1.55, p = 0.89, I2 = 0%), ischemic stroke (RR - 0.76, 95% CI: 0.5-1.15, p = 0.19, I2 = 0%), all-cause mortality (RR - 1.06, 95% CI: 0.85-1.31, p = 0.61, I2 = 0%) and MACE (RR - 1.06, 95% CI: 0.91-1.22, p = 0.97, I2 = 0%).

Conclusion

Compared with triple therapy with VKAS, double therapy with DOACs is associated with a reduced risk of bleeding and is as effective in patients with AF undergoing PCI.

Abstract Figure.
1260Transvenous lead extraction: efficacy and safety of the procedure in octogenarian patients
Authors: Giannotti Santoro M , Segreti L , Zucchelli G , Barletta V , Fiorentini F , Di Cori A , Della Tommasina V , De Lucia R , Bongiorni M G
Published: June 2020

Introduction

the management of patients with infection or malfunction of a cardiac implantable electronic device (CIED) may be challenging.

Purpose

The aim of the study is to evaluate the safety and efficacy of transvenous lead extraction (TLE) in elderly patients.

Methods

a retrospective analysis of patients who underwent to TLE in our center was performed. Patients were divided in two groups: 1) patients 80 years of age or older, 2) patients younger than 80 years. All patients were treated with manual traction or mechanical dilatation.

Results

our analysis included 1316 patients, with a total of 2513 leads extracted. Group 1 (≥80 years) counted 202 patients and group 2 (<80 years) 1114 patients. The group of elderly patients presented more comorbidities, as hypertension, chronic kidney disease, atrial fibrillation and pulmonary disease. Patients 80 years of age or older had more pacemakers than ICDs, whereas the dwelling time of the oldest lead, the number of leads and the presence of abandoned leads was similar despite patients age. In group 1 the rate of radiological success for lead was higher than in group 2 (99.0% vs 95.9%; P < 0.001). The clinical success was obtained in 1273 patients (96.7%), without significative differences between groups (98.0% vs 96.4%; P = 0.36). Major complications occurred in 10 patients (0.7%), without significative differences (1.5% vs 0.6%; P = 0.24) (figure 1).

Conclusion

TLE in elderly patients is a safe and effective procedure. In patients older than 80 years there are not more major complications than in younger patients, and the efficacy of the procedure seems to be superior.

Abstract Figure 1