bluuebunny/crossref_metadata_2025 huggingface dataset:
Microfluidic chips for real-time PCR
Authors: Zubik A N , Rudnitskaya G E , Bulyanitsa A L , Lukashenko T A , Evstrapov A A
Published: December 2021

The results of real-time PCR in single-chamber microfluidic chips made of silicon-glass materials and optically transparent polymethyl methacrylate are presented. Conditions for efficient thermal cycling in microchip devices with several reaction chambers are discussed. A simplified theoretical estimation of the duration of heating a liquid in a polymer microchip is proposed, the results of which correlate with experimental data.
Encapsulation of Recrystallized Inorganic Perovskite Quantum Dots in Nonwoven Fluoropolymer Fibers
Authors: Baeva M , Neplokh V , Markina D I , Pavlov A M , Kirilenko D A , Mukhin I S , Pushkarev A P , Makarov S V , Serdobintsev A A
Published: December 2021

Since emerging Metal Halide Perovskites were attracting elevated attention from scientific and industrial communities. Although, we still yet to see commercial products based on perovskite materials a significant body of work has been already done. Here we present our own method of Metal Halide Perovskites integration into possible industrial applications. Our way of Perovskite Quantum Dots encapsulation in polymer fibers provides exceptional water and ambient stability as well as optimal photoluminescence.
On necessity for analytical solution of the Bloch equations for nuclear magnetic resonance signals at condition express control of liquid medium
Authors: Davydov M N , Davydov V V , Rud V Yu
Published: December 2021

The necessity of using express analysis methods to control medium condition is substantiated. It has been shown that the method of express control based on the phenomenon of nuclear magnetic resonance is one of the most preferable. It was found that to increase the information about the medium condition state obtained from the recorded NMR signal, it is necessary to use a mathematical model (based on analytical solutions of the Bloch equations). Two approaches are considered that are used to describe the NMR signal in a liquid medium. It is determined that in the classical approach in the system of Bloch equations it is possible to take into account the peculiarities of using radiotechnical methods of signal registration. The direction of the analytical solution of the Bloch equation is proposed. The experimental data are compared with the numerical solution.
Fiber-optic sensor for remote monitoring the γ-radiation of various powers
Authors: Dmitrieva D S , Davydov V V , Rud V Y
Published: December 2021

The necessity of improving the metrological characteristics and functional capabilities of the fiber-optic sensor for measurements at the large distances (more than 10 km) is substantiated. The new method for constructing a communication line with the fiber-optic sensor for controlling exposure dose in a large range of its variation (several orders of magnitude) in a remote mode is proposed. The functional capabilities of the sensor are determined; its connection setup and measurement limits are developed. The experimental results are presented.
Structure and spectral properties of Fe:ZnAl2O4 transparent glass-ceramics and ceramic
Authors: Eremeev K , Basyrova L , Dymshits O , Balabanov S , Belyaev A , Alekseeva I , Khubetsov A , Tsenter M , Volokitina A , Zhilin A , Popkov V , Loiko P
Published: December 2021

Transparent glass-ceramics based on iron-doped ZnAl2O4 (gahnite) nanocrystals were prepared by melt-quenching (at 1580 °C) with subsequent heat-treatments (at 720 – 1050 °C). Polycrystalline transparent Fe:ZnAl2O4 ceramic was synthesized by hot pressing of powders (at 1600 °C, 50 MPa) using the sintering additive, ZnF2. A comparative study of the structure, Raman spectra and absorption properties of these materials was performed.
On the possibility of using the optical method for express quality control of fruits
Authors: Gryaznova E M , Davydov V V , Rud V Y
Published: December 2021

The necessity of express control of fruit quality in various situations has been substantiated. Various methods for the implementation of express control of fruit quality in express mode are considered. A method for express control of fruit quality using laser radiation has been developed. The change in the degree of spatial coherence in the recorded reflected laser radiation from defects on the surfaces of fruits was investigated. Experimental results of the study of various defects on fruits, as well as their hardness and degree of ripening, are presented using the method developed by us.
Features of the construction of photonic integrated circuits for communication systems
Authors: Popovskiy N I , Davydov V V , Rud V Yu
Published: December 2021

The article discusses the main methods of signal processing in a coherent optical transport network based on a photonic integrated circuit to increase the speed and the onset of the terabit era in optical transport networks, cloud and high-performance computing systems. The properties and operational characteristics of the main material platforms of photonic integrated circuits and their future technological units are considered.
Thermo-optical properties of silicon nitride Mach-Zehnder interferometer for the on-chip quantum random number generator
Authors: Prokhodtsov A , Kovalyuk V , An P , Golikov A , Konyshev Y , Shakhovoy R , Sharoglazova V , Udaltsov A , Kurochkin Y , Goltsman G
Published: December 2021

Here we study the thermo-optical properties of an on-chip silicon nitride Mach-Zehnder interferometer (MZI). The spectral shift of the MZI is associated with a change in the chip temperature. This can be explained by a change in the splitting ratio of the directional couplers, as well as a significant change in phase difference between waveguide arms. We experimentally found a phase shift of 2π when heated by 1.67 °C and changes in resonant wavelength at different temperatures (dλ/dT) equal 12.0 pm/°C, theoretically obtained a formula for an arbitrary splitting ratio of the directional couplers in an MZI, and determined the temperature stability required to the device operation inside a quantum cryptography system.
Discrete optical Zeno effect for polarization of light
Authors: Sedykh K O , Sych D V
Published: December 2021

Quantum Zeno effect concerns deterministic dynamics of a quantum system induced by a series of projective quantum measurements. Applying this effect in optics, one can achieve an arbitrary lossless transformation of linear polarization of light with help of linear polarizers. However, to demonstrate this effect in practice, we have to take into account unavoidable losses in each polarizer that limits probability of successful transformations. In this work, we theoretically study a realistic quantum Zeno effect with an optimal discrete set of polarizers and find the maximum success probability
Simple representation of the quantum entanglement of coupled harmonic oscillators in terms of the reflection coefficient
Authors: Tsykareva Yu V , Makarov D N
Published: December 2021

Quantum entanglement of coupled harmonic oscillators is frequently applied in quantum and non-linear physics, molecular chemistry and biophysics, which is why its study is of a great interest for modern physics. In this work a quantum entanglement of a coupled harmonic oscillator in a simple form was found. This simple form is presented as a single parameter – reflection coefficient R. All parameters of the studied system are included in the R coefficient. It is shown that the derivation of the expression can have applications in quantum optics, in particular in quantum metrology.
Identification of pigments of Russian icons by means of X-ray fluorescence spectroscopy
Authors: Vasilieva A V , Parfenov V A
Published: December 2021

In this work the analysis of paint layers of Russian icons of the 16th-19th centuries was carried out by means of X-ray fluorescence spectroscopy. The data obtained on the elemental composition of pigments made it possible to identify them. Main problems of identification were described in this paper. The results of the research will be used to create a database of XRF-spectra of pigments, which were used by Russian icon painters of certain schools and time periods.
Performance of microheaters for tunable on-chip interferometer
Authors: Venediktov I O , Elezov M S , Prokhodtsov A I , Kovalyuk V V , An P P , Golikov A D , Shcherbatenko M L , Sych D V , Goltsman G N
Published: December 2021

Mach-Zehnder interferometer (MZI) is a valuable practical tool in many optical science areas. In particular, high-contrast MZI are required for experimental realization of displacement-based quantum receivers that can discriminate weak coherent states of light with the minimum error rate. In this work we study phase modulators of tunable on-chip interferometer on silicon nitride (Si3N4) platform for telecom wavelength (1550 nm) consisting of several MZI. Phase modulators on one of the arms of MZI consists of microheaters and waveguide. Microheaters heat waveguides changing its refractive index due to thermo-optical effect providing a phase shift. We measure the bandwidth of phase modulators and study their operation in pulse mode.
Photoionization of polarized doublet states of Xenon atom
Authors: Viktorov E A , Pastor A A , Serdobintsev P Yu , Miculis K , Bezuglov N N
Published: December 2021

We studied experimentally and theoretically the ionization of a two-photon excited superposition of 4f states of Xe atom by probe femtosecond pulse laser in a supersonic beam. The revealed oscillation structure in the observed photoionization signals is associated with the interference of the coherently populated components of Xe doublet states. Our results demonstrate the high efficiency of proposed experimental scheme for registering quantum beats in the photoelectron current.
Polarized spectroscopy of electric and magnetic dipole transitions of Europium (III) ions in C2 sites
Authors: Volokitina A , Loiko P , Dunina E , Kornienko A , Serres J M , Aguiló M , Díaz F , Pavlyuk A , Mateos X
Published: December 2021

Polarization anisotropy of luminescent properties of europium (III) ions in low-symmetry C2 sites is studied using monoclinic (sp. gr. C2/c) tungstate crystal KY(WO4)2. The 5D0 → 7FJ (where J = 0…6) transitions are characterized for the principal light polarizations. Polarization selection rules for the magnetic dipole 5D0 → 7F1 transition are presented. The stimulated-emission cross-sections for Eu3+ ions relevant for laser operation are determined.
Lithium aluminosilicate glass-ceramics for low-temperature anodic sealing of MEMS sensors
Authors: Kleimanov R , Komarevtsev I , Enns Y , Akulshin Y , Korshunov A , Shashkin A , Arefiev D , Kazakin A
Published: December 2021

The results of a study of the anodic bonding parameters of transparent glass-ceramics based on lithium aluminosilicates which are promising as structural materials of MEMS and MOEMS sensors are presented. A comparison of the optical transmittance of these materials and classical for MEMS industry glasses has been carried out. The glass-ceramics electrical conductivity in a wide temperature range has been measured. The procedure of hermetic sealing of glass-ceramics by the anodic bonding at temperatures of 150 – 250 °C has been worked out. A prototype of glass-ceramic atomic cell has been fabricated.
Influence of laser processing conditions on the depth and microhardness of layers formed on titanium
Authors: Koshuro V , Osipova L , Markelova O , Fomina M , Fomin A
Published: December 2021

In this work, we studied the depth and microhardness of the layers formed on titanium during laser processing in a graphite environment. The energy and duration of the laser pulse varied from 0.76 to 10.17 J and from 0.5 to 3 ms, respectively. As a result of processing, the formation of layers characterized by a depth of 8.3-800 μm and a microhardness of 9.68-28.01 GPa took place. Regression models are constructed that describe the effect of laser processing conditions on the indicated characteristics of the layers. It was found that the pulse energy had the greatest effect on the depth and microhardness of hardened titanium.
Features of Electrophoretic Formation of Local Heat Sources Based on Nanosized Powder Al
Authors: Leonenko E S , Sorokina L I , Ryazanov R M , Lebedev E A
Published: December 2021

In this study, the features of electrophoretic deposition (EPD) method to form nano-Al based energetic layers were investigated. The influence of solvents and additive components on the EPD process was analyzed, and the optimal composition of the suspension for the best deposition of layers based on nanoscale Al particles was acquired. The obtained layers can be used as an initiator of secondary reactions for on-chip energetic systems and a local heat source for joining surfaces by reactive bonding.
Analysis of frequency response sensor of MEMS gyroscope in vacuum chamber
Authors: Lysenko I E , Naumenko D V , Ezhova O A
Published: December 2021

This article presents a study of the frequency response of a MEMS gyroscope in a vacuum chamber. On the basis of experimental studies by the method of laser Doppler vibrometry, the dependences of the amplitude of oscillations of the inertial mass in the vertical plane at various pressures are obtained. The bandwidth of the MEMS sensor was also measured.As a result of the experiments, the damping factors were determined to compose a more complete mathematical model and for more accurate finite element modeling in ANSYS, and refined parameters of the electrostatic drive and the amplitude of oscillations along the axis of the drive were obtained. These studies will be useful for determining the residual degree of vacuum in the case for further frequency tuning of the device.
Research of FIB local milling processes for creation of nanosized field emission structures
Authors: Panchenko I V , Shandyba N A , Kolomiytsev A S
Published: December 2021

The paper presents the results of experimental studies of the influence of the main parameters of a focused ion beam (FIB) during surface profiling on the accuracy of transfer of a pattern to a silicon substrate to create nanoscale field emission structures. In this work, the optimal FIB currents are determined, introducing a minimum amount of distortions during the formation of structures of various sizes. The possibilities of the method of local ion-beam etching of structures in a wide range from 0.1 to 2 μm are shown. The prospects of using this technology for the creation of field emission structures have been demonstrated. It is determived the current-voltage characteristic of the fabricated field-emission cells with a threshold voltage of the onset of emission of ∼ 2.5 V and a maximum current of 300 nA at 30 V.
Properties of plasma enhanced atomic layer deposited ruthenium thin films from Ru(EtCp)2
Authors: Smirnova E A , Miakonkikh A V , Rogozhin A E , Rudenko K V
Published: December 2021

Ruthenium thin films were deposited by plasma enhanced atomic layer deposition using bis(ethylcyclopentadienyl)ruthenium(II) or Ru(EtCp)2 and oxygen plasma. The growth characteristics have been studied on a silicon substrate with different interfaces in a wide temperature range. On Si and SiO2, a nucleation delay period has been observed, which can be substantially reduced by the use of a tantalum nitride underlayer of ∼ 0.3 nm. The surface analysis shows that the substrate’s temperature strongly affects the composition of the film from ruthenium oxide at low temperatures to pure ruthenium film at higher temperatures.
Initial Characterization of Bio-Slurry as Liquid Fertilizer
Authors: Kusuma M , Afrianisa R
Published: December 2021

The demand for organic fertilizers in Indonesia is currently in a critical state. In 2015, it was noticed that the demand of Indonesia for NPK fertilizers reached over 6.5 million tons per year. Given the current state of demand for organic fertilizers in Indonesia, it is imperative to have alternative organic fertilizers that are environmentally friendly and readily available raw materials. One alternative is to use biogas waste that contains essential plant-based nutrients such as NPK (nitrogen, phosphorus, potassium) and additional nutrients such as magnesium (Mg), calcium (Ca) and sulfur (S). The composition of Bio-Slurry after fermentation consists of 25% ± 5 dry matter and 75% ± 5 water. If the dry substance is decomposed, it contains 18- 27% organic matter. The production of liquid organic fertilizers from BioSlurry requires some anaerobic fermentation process lasting 20 days. During the fermentation process it is necessary to additional raw materials such as cow urine, banana stalk and banana peel to add the N, P and K values to BioSlurry. In the initial characterization test, BioSlurry liquid (after pressing) showed an NPK value of <1% and a C-Organic value of 0.04.
Characteristics of Separation and Induced Drag in the Use of Swept-back Wing Unmanned Aerial Vehicle
Authors: Setyo Hariyadi S P , Sutardi  , Sukahir  , Jamaludin
Published: December 2021

The swept-back wing has been used in almost all aircraft wings. This is necessary to reduce the pressure drag from the wings so that there is an increase in aerodynamic performance. The aerodynamic performance is the ratio between the total drag coefficient and the lift coefficient. This research attempts to explain the swept-back wing phenomenon in unmanned aerial vehicles (UAV) on Eppler 562 airfoil. The numerical simulation uses the k-ε turbulent model at Reynolds number (Re) = 2.34 x 104. Variation of backward swept angle Λ = 0°, 15°, and 30°. The separation growth Λ = 0° occurred more on the wing root, while Λ = 15° and Λ = 30° occurred more on the wingtip. At Λ = 15°, as the angle of attack increases, the area of the separation increases, and the area of the transition towards the separation decreases. The reattach area also has an increase in the area of the trailing edge. At Λ = 30°, with an increase in the angle of attack, there is a shift from the wingtip area to the mid-span. The area of separation and transition to separation has increased significantly. The re-attach area at α = 8o has not been seen, so at α = 12o it has been seen significantly. The vorticity on the x-axis shows Λ = 15°, and Λ = 30° has a wider area while on the z-axis, Λ = 15°, and Λ = 30° have stronger vortex strength. However, in the mid-span, Λ = 0° has a stronger result.
The Geologic Process of The Saka River area: Related to the History Woyla Elevated Ocean in The South Sumatra Island Region, Republic of Indonesia
Authors: Idarwati  , Purwanto H S , Sutriyono E , Prasetyadi C
Published: December 2021

The lithological and earth structures which compose the geologic process space are terribly fascinating to study. elaborated investigation of pre-tertiary rock subduction at the Woyla web site is rarely carried out. the variability of rocks derived from the Woyla oceanic plate, that folded on the West Sumatra continental plate within the Age of Reptiles era, illustrates the magnitude of the subduction impact mirrored in the structures that are still reflected in the abandoned rocks. The ways want to discover this subduction event are elaborated field observations, skinny section, XRD, and earth science structure measurements, supported by drones and satellite imagery. The lithology of basalt, flint, serpentine, marble, and arenaceous rock is vital to the presence of the Intraoceanic Arch of Woyla within the Saka phase. elaborated structural calculation show that the Saka segment went through several tectonic stages from the Mesozoic to Recent, that is mirrored in the Saka fault and therefore the Penanggungan fault.
Analysis of Ammonia in Kali Lamong River Estuary Surabaya during Pandemic Covid-19
Authors: Ni’am A C , Prasetya K D , Utami R P
Published: December 2021

Water quality monitoring is an important instrument in the management of freshwater resources because they offer essential information about the physical, chemical, and biological water resources status, determining patterns and changes over time, and identifying emerging water quality issues especially in a specific situation. This study investigates the ammonia concentration in Kali Lamong river estuaries Surabaya to comprehensive the level of pollution that occurs during pandemic Covid-19. This research was conducted in the river downstream of Kali Lamong in the dry season. Sampling has occurred in 3 stations. Each station has 3 sampling sites that were ¼ of the left side, ½ from the side of the left, and ¼ of the right side. The measurement ammonia in water was measured by SNI 06-6989.30-2005 method. The laboratory result depicted the highest of ammonia concentration (0.765 mg/L) at B1 site. The ammonia concentration in water was <0.02 to 0.13 mg/L in another site. The water sampling result was classified based on PP number 22 of 2021 implementation of protection and management of environment in sixth appendix about national water quality standard with third-class purpose.
Design and Control Motorized Circuit Breaker in Electrical Distribution Panel
Authors: Sudjoko R I , Hartono  , Suhanto  , Kustori  , Hariyadi S , Faizah F
Published: December 2021

A circuit breaker is the main part of the distribution panel that needs to control for safe operation. It is important for protection and switching in the power system. Automatic control of circuit breakers using motorized can be realized by the microcontroller scheme. In this paper, a microcontroller equipped with wifi and an internet connection is used to control and monitoring the circuit breaker. The design of the circuit is proposed and experiment result is obtained. The response time is about 1 second to complete the process to control the circuit breaker. Error in monitoring application is about 3% for voltage measurement and 3.5% for current measurement. The proposed circuit system showed good and reliable control and monitoring of circuit breakers in every condition include of closing, opening, and monitoring.
Parameter Variation of Microwave Torrefaction Time of Blotong and Bagasse Briquettes
Authors: Mirzayanti Y. W. , Bhismoko B. , Fathurrahman M. Q. , Ningsih E.
Published: December 2021

Briquettes are one way to increase the economic value of biomass. Blotong and bagasse are two biomass wastes that can pollute the environment if stored for an extended period of time. This study aimed to determine the effect of torrefaction time on the heating value of briquettes, moisture content, and the number of organic carbons. Blotong and bagasse microwave torrefaction uses 1000 watts of power and time intervals of 20, 30, 40, 50, and 60 minutes. When the best take for torrefaction between blotong and bagasse with molasses is compared, the result is 1:1:4. Based on the analysis results, the best briquettes produced have a water content of 2.1 percent, a calorific value of 5475.8 cal/gram, and an organic carbon content of 64.75 percent at a time variable of 60 minutes. These results indicate that variations in the torrefaction process time can affect the characteristics of the resulting briquettes. Based on the results obtained, the longer the torrefaction time, the lower the water content in the briquettes. Likewise, the calorific value and carbon content are also getting higher.
Study of the Effect of Time Variations on the Leaching Process of Ferronickel Products from Mini Blast Furnace to Yield Elements of Fe, Ni, and Co for NiSO4.6H2O Synthesis
Authors: Pintowantoro S , Waluyo FP , Setiyorini Y , Setyowati VA , Kawigraha A , Abdul F
Published: December 2021

Indonesia, as one of the biggest contributor to air pollution, has a solution to replace petroleum-powered motorized vehicles with battery-powered electric vehicles (EVs). Indonesia has nickel reserves that can be used as one of the cathodes of a Li-ion battery called NMC. In this research, the author uses ferronickel ore from the smelting process of laterite nickel ore. Then ferronickel is leached to produce nickel sulfate. This research was conducted to determine the effect of variations in leaching time (2 hours, 4 hours, 6 hours, 8 hours, 10 hours) on the extraction rate, extraction percentage, chemical composition, yield, and the resulting compounds. The results of this study were that the highest content of nickel extract was produced in a 10-hour variation of 11530 mg/L with an extraction percentage of 94.16%, the most iron in a 10-hour variation of 4128 mg/L with 100% extraction percentage, and the most cobalt in a 2-hour variation. as much as 47.3 mg/L with 100% extraction percentage. The highest nickel yield was produced at a 10-hour concentration variation of 87.37%. The compounds produced from the crystallization products were NiSO4.6H2O, Na2SO4, CoSO4, and FeSO4.
Chemical and Physical Activation Using a Microwave to Increase the Ability of Activated Carbon to Adsorb Dye Waste
Authors: Udyani K , Purwaningsih D Y
Published: December 2021

This study aims to develop an android-based application to calculate the amount of fuel adjusted to the distance and speed of the ship based on the trajectory (way point). The calculation of distance in this application uses the concept of a spherical triangle which is used in voyage navigation. This development adopts the Waterfall model with the stages of Requirement Engineering, Design and implementation, Testing, Release and Maintenance. At the product review stage, it involves software experts (to provide criticism and suggestions for improvement), then testing is carried out by comparing the results of calculations using applications with manual calculations and ECDIS (electronic Chart Display Information System). The test results show that there is no significant difference between the results of calculations using the application with manual calculations and ECDIS. Thus, this application can be used to calculate the amount of fuel needed according to the distance traveled and the speed of the ship based on the selected trajectory.
Optimization of Paddle Wheel Aeration, a preliminary study of Integrated Smart Aquaculture System
Authors: Nugroho P N A , Mustaghfirin M A , Pambudi D S A , Imron A , Aminudin M R , Wulandari D A
Published: December 2021

The paddlewheel aerator is one of the supporting facilities in the intensive aquaculture pond system. Assuming all the land uses an intensive cultivation system, more than two million paddlewheels worth more than 10 trillion will be needed by 2024. Currently, all paddlewheels are produced abroad or imported. This is very unfortunate considering the vast market potential. This paper discussed a preliminary study of developing paddlewheel aeration for shrimp ponds using an integrated intelligent aquaculture system to support intensification. Two paddlewheel aerators with modifications in the gearbox have been successfully installed. Based on the observation and user’s testimony, the newly installed paddlewheel was quite good, the sound of the motor was smooth, then the flow range was longer, the coverage area was more expansive than the existing waterwheel. This research would be a foundation for intelligent paddlewheel aeration design that can be developed domestically to support local industry in Indonesia.
TNT equivalent of the shock wave energy generated during the supersonic flight of an aircraft
Authors: Drobzheva Ya V , Zikunkova D V , Krasnov V M
Published: December 2021

To assess the impact on human health of the sonic boom that occurs when an aircraft is flying at supersonic speed, and, accordingly, to solve the problem of noise reduction by optimizing the aircraft design, it is proposed to evaluate the shock wave energy using the TNT equivalent of a cylindrical explosion. An example of calculating the shock wave energy during flights of F4 and F18 aircraft at different altitudes is considered. To calculate the evolution of an acoustic pulse during its propagation from the boundary of the shock wave transition to the acoustic one, the wave equation and its solution are used, taking into account the inhomogenei-ty of the atmosphere, nonlinear effects, absorption and expansion of the wave front, as well as the results of ground-based measurements of acoustic pulses. The results of calculations of the dependence of the explosion energy on the flight altitude, as well as on the type of aircraft are explained on the basis of the formula for the atmospheric resistance force.
Influence of thermoactivation on properties of mineral additives in dry mixtures
Authors: Loganina V I , Laskov N N , Boldyrev G G
Published: December 2021

Information on the effect of thermal activation of silicate and aluminosilicate rocks used as a filler in dry building mixtures on their reactivity of interaction with lime binder is presented. The change in the distribution of acidic Bronsted and Lewis centers on the filler surface as a result of thermal activation is shown. It was found that the number of Bronsted and Lewis acid centers on the surface of fired clays exceeds the number of the same centers on the surface of unbaked clays. The number of adsorption centers at pKa from 0 to 7 and pKa> 13 on the surface of fired diatomite is 2.435 * 10-5 mol/g, and on the surface of unbaked diatomite -1.678 * 10−5 mol/g. The heat treatment of diatomite at low temperatures (2000C and 3000C) does not significantly affect the values of the compressive strength of the mortar. An increase in the firing temperature to 7000C leads to an increase in strength characteristics up to R = 4.38 MPa. However, the greatest effect is achieved when diatomite is fired at a temperature of t = 9000C. The value of the ultimate strength in compression was R = 5.1 MPa.
On the reduction of hydraulic resistance based on the hydrophobization of functional surfaces
Authors: Dasaev M R , Trushin E S , Kalakutskaya O V , Voloshenko A P
Published: December 2021

Analysis of various studies has shown that one of the most promising ways to reduce hydraulic resistance in pipelines during transportation of liquid fluid is a method based on changing the wettability of functional surfaces, i.e. hydrophobization. This paper presents the results of experimental studies of the effect of hydrophobization of pipe surfaces on hydraulic losses. For this purpose, experimental tube samples of steel (20Kh13) were made, on the surface of which a spiral relief was formed using laser equipment, resulting in a hydrophobic state, and the value of the contact angle was 160.7°. From the analysis of the results of experimental studies, the dependence of hydraulic resistance on Reynolds number was obtained, from which it follows that the use of hydrophobic surfaces during water transportation helps to reduce the hydraulic resistance to 9.7%.
The use of plant materials for the synthesis of superplasticizer
Authors: Poluektova V A , Cherkashina N I , Starchenko S A
Published: December 2021

The paper presents data on the synthesis of phloroglucinol-furfural modifier (1,3,5-trihydroxybenzene-2-furaldehyde oligomer) based on 2-furaldehyde (furfural) and 1,3,5-trihydroxybenzene (phloroglucinol). The synthesis of a modifier with different molar ratios of phloroglucinol/furfural was carried out. It was found that an increase in the molar ratio leads to an increase in the plasticizing ability of the modifier. The optimal concentration of the catalyst was determined to be equal to 50% by weight of phloroglucinol. Two chemical forms of the modifier were obtained: H-form and Na-form. The structure of various forms of the modifier has been studied by scanning electron microscopy. It was found that the oligomers used in the work for the synthesis of the modifier, in addition to 2-furyl methyl alcohol, do not have plasticizing properties. Purified 2-furyl methyl alcohol has weak plasticizing properties. It is shown that to achieve the best plasticizing effect, it is necessary to gradually introduce a condensing agent into the reaction mixture. With gradual introduction, a complete condensation reaction occurs between the monomers, which affects the improvement of the plasticizing properties of the resulting product. The spread of the cement mixture when using 0.3% of the additive based on the mass of cement in terms of dry matter is 19 cm.
Synthesis of Different Nanoparticles for Biological Application
Authors: Deng Zhaoren , Gong Ming , Li Yue
Published: December 2021

Compared with traditional materials, the application of nanomaterials in biomedical fields will bring many excellent performances. This review summarizes some new developments and applications of nanoparticles in recent years from the perspective of biology and medicine, including magnetic resonance imaging, treatment for Alzheimer’s disease, diabetes and plant infection disease, oxygen-releasing scaffolds, engineered water nanostructures (EWNS) based sanitizer, drug loading system and cancer treatment. This article summarized and discussed the synthesis methods, characterization, advantages, and applications based on these aspects. Introducing nanoparticles into biomedical fields can provide useful ideas for applying nanoparticles in biology and pharmacy in the future.
Study on the Ablation Properties of Nano-graphite Modified EPDM Insulators
Authors: Wang Wentao , Zhou Lisheng , Li Yang , Li Peng , Chen Guohui , Yang Shishan
Published: December 2021

To improve the anti-ablative property of EPDM-based composites, nano-graphite powder as anti-ablation filler was introduced to optimize the EPDM insulation material formulas. Characterization of anti-ablation performance showed that the composite at the nano-graphite content of 10phr exhibited the best anti-ablation and mechanical performances, such as: a linear ablation rate of 0.062 mm/s, a mass ablation rate of 0.048 g/s, tensile strength of 5.69 MPa and Elongation at break of 391.2%. The nano-graphite was proven to be an effective material which is beneficial to improve the anti-ablation of the EPDM composites.
Effect of Si Content on the Properties of A356 Aluminum Alloy
Authors: Wu Lei , He Bing , Li Weidong , Qin Ming
Published: December 2021

The effects of different Si contents on the microstructure and mechanical properties of A356 aluminum alloy were studied by metallographic microscope analysis and tensile property test. The results show that when the silicon content is between 7% and 11 %, with the increase of silicon content, the eutectic silicon in the matrix increases, and the tensile strength and elongation decrease. When the silicon content increased to 13%, the primary silicon structure appeared in A356 aluminum alloy, and its mechanical properties increased.
Treatment for gap and step nonconformity of slat on tail-hang civil aircraft
Authors: Zhu Weibin , Wang Suxiao , Lan Jian
Published: December 2021

Slat aerodynamic contour nonconformity often occurs during the manufacture of civil aircraft, which can cause appearance influence, drag increase and even manoeuvrability & stability problem. This article introduces 4 types of gaps and 3 types of step nonconformity and reason for them. Then the article studies treatment principle for wing slat contour nonconformity. In the end, the article figures out acceptable criteria and 5 types of standard repair methods for slat gap and step nonconformity.
Analysis of Tooth Surface Contact Stress of Involute Spur Gear
Authors: Zhai Yusheng , Mu Jie , Yun Ruiguang , Jia Siran , En Jianfeng , Gao Zhenbang , Quan Baochao , Yang Guicheng
Published: December 2021

Through the establishment of a pair of spur gear contact models, based on Hertz contact theory, the tooth surface contact stress is calculated; then the Ansys finite element analysis software is used to simulate and analyse the stress distribution. Through the analysis and comparison of the two results, it is proved that the contact stress calculated by Hertz theory is relatively small, which is close to the results of the finite element simulation analysis. Theoretical calculation can verify the accuracy of the finite element simulation analysis model, and the finite element simulation analysis provides an effective way to accurately calculate the contact stress of the tooth surface.
Geodiversity and Geoconservation in Yuanmou Basin, Yunnan Province, China
Authors: Cheng Xianfeng , Qi Wufu , He Ping , Zhang Shitao , Shi Liang
Published: December 2021

Geodiversity is considered as abiotic diversity, and it is the foundation of geopark, geotourism and geoconservation. Yunnan Province is the typical area abundant in geodiversity in China. Geodiversity of Yuanmou Basin, which is located in North Yunnan, possesses scientific, cultural, aesthetical, ecological values. Howerver, there are some problems, such as underexploitation, inadequate protection, even destruction in the area. Research of geodiversity will provide a new idea for sustainable development in Yuanmou Basin.
Ore Features and Gold Occurrence of the Manlonggou Gold Deposit, Southeast Yunnan Province, China
Authors: Qi Wufu , Cheng Xianfeng , Huang Qianrui , Liu Yu , Ran Shirong , Zhang Yanqiang
Published: December 2021

The Yunnan-Guizhou-Guangxi “Golden Triangle” is one of the famous Carlin-type gold deposits in China and even in the world. Manlonggou gold deposit is a newly discovered gold deposit in this area. The host rocks are mainly lithic quartz sandstone, siltstone and silty mudstone above Caledonian unconformity. The main minerals in ores are natural gold, limonite, hematite, pyrite and so on. The occurrence state of gold is fine exposed and semi-exposed natural gold, as well as gold encased by limonite, carbonate, quartz and silicate minerals. The deposit can be a fine grain hydrothermal altered gold deposit with the origin of tectonic-medium-low temperature hydrothermal percolation.
Improving Characteristic Parameters of Memristor Based on HfO2 Active Layer
Authors: Kushitashvili Z. , Bibilashvili A.
Published: December 2021

The improvement of the characteristic parameters of the memristor depends on the factors such as thickness and surface area of the active layer. These parameters define leakage currents, which is the main disatvantige of the memory storage device and to improve the electrical features the leakage currents must be dropped to the zero in ideal case. In the presented work is described the electrical isolation of the active layer from the substrate by the thin layer of photoresist, which is an electrical insulator. For reducing area was used the new fotomask, which is able to reduce area 100 times. The memristor structures are designed in the form of “crossbars”, which allows us to individually investigate each memristor and create a database with the possibility of incorporating it into the microchip in the future. In this work is presented also research outcomes regarding to selection memristor’s contacts and active layers. As contacts are overviewed tungsten (W), titanium nitride (TiN) and aluminum (Al). Is considered metal and transition metal oxides as active layers WOx, HfO2, WOx +HfO2, HfO2 + HfOx. The oxide electrical and structural properties is defined from I-V, C-V, XRD and XPS characteristics.
Possibility of Monitoring of Movement on Cracks for Solid Rocks
Authors: Neuman David , Yang Shuran , Sombathy Erik
Published: December 2021

The main goal of this article is to analyze the possibility of measuring on cracks. For measuring the distance between points, e.g. crackmeters are used. When measuring cracks in rock masses, very precise instruments are used, which are referred to as dilatometers. These dilatometers are based on a mechanical or electrical principle and measure directly inside the fracture, as opposed to a crackmeter where we measure on both outer sides of the fracture. Measuring on cracks is one of the methods of evaluating the development of slope deformation on the surface. If cracks appear on the slope, we can use the crackmeter to start more frequent and accurate control of the slump movement by measuring the relative changes in position using appropriately selected stabilized points on opposite sides of the crack. If we know the direction of movement, we can use only two points to check debonding cracks. If we are measuring marginal cracks, a three-point system is appropriate. Two points are placed outside the landslide and one is placed directly on the landslide. The principle of the measurement consists in evaluating the change in distance of two points (short anchors) firmly connected to the surrounding environment and located in the simplest case on opposite sides of the crack. Crackmeters are also used to measure movements across open tension cracks and scarps delimiting the boundary of the potential slide mass.
Stability of the bedrock of castle building for geotourism purposes
Authors: Duraj Miloš , Niemiec Dominik , Mendes Estevao , Sombathy Erik
Published: December 2021

The geological structure of the Slovak Republic is very complex and varied. This fact in the course of centuries has had an impact on the castle buildings built here. The subsoil of these structures has different petrographic composition, tectonic disturbances and other geological complexities that threaten the stability of these structures and endanger the objects in their surroundings. In recent years, these structures have begun to receive deserved attention. In the past, the problems of severely disturbed blocks in the subsoil were mainly addressed and had to be rehabilitated for these reasons. These were mainly buildings whose subsoil is built with carbonate rocks. A perfect example of a long-term solution to these complex problems is also the Strecno Castle. A lot of effort and money has already been devoted to solving the stability of the bedrock, which also adversely affects the stability of the castle. However, the extensive set of works that have been carried out here over a long period of time have not brought a complete solution to the problems that occur here. For this reason, continuous work is being carried out here under the guidance of experts to eliminate the effects of erosion of the bedrock in particular. In the present work, the activities and measures that have been implemented here in stages up to the present are briefly described chronologically.
Geotourism interesting locality with Remediation of the bedrock and restoration of Spiš Castle - UNESCO heritage site
Authors: Montero Orlando Arencibia , Duraj Miloš
Published: December 2021

Understanding the structure of the geological subsoil should be the first stage in the construction of any major building. Therefore, if the problem of rescue and restoration of various historical buildings is currently being addressed, it is necessary to study their subsoil in detail. Among the important historical buildings that have been preserved in Slovakia are numerous castles and chateaux. Nowadays, many of these buildings need to be extensively restored to prevent their gradual devastation. The issue of rehabilitation of some buildings has been addressed for several decades. The reasons for the rehabilitation of these buildings have varied. In the case of the ruins of Strečnian Castle and its subsoil, it was primarily the safety of traffic on the adjacent important road. In the case of Spiš Castle, it is a monument of world importance. It is one of the largest castle complexes in Europe. The beginnings of the construction of this complex date back to the 11th century. Its current state is due, among other factors, to the instability of its geological subsoil. For this reason, the stabilisation of the travertine body, which has been severely damaged, particularly by tectonics and karst processes, has already been addressed in the past. The solution of this problem in the past has already produced positive results, but due to exogenous processes and, hypothetically and certainly, seismicity, the bedrock may move again in the future. For this reason it is necessary to pay attention to continuous monitoring of the movement of its rock blocks. As far as the castle itself is concerned, its current state is mainly due to the fire at the end of the 18th century, followed by its rapid devastation. In view of the world importance of the castle, the restoration of the site may therefore also take other directions. One possibility is, for example, its reconstruction according to contemporary records, which would bring its final appearance even closer to its original grandeur.
The Visualization Representation of Space-Time-Path in The Space-Time-Cube
Authors: Song Bingbing , Wang Yanlin , Li Fang
Published: December 2021

Map is a traditional visualization tool to represent distribution and interaction of spatial objects or spatial phenomenon. However, with the continuous development of acquisition and processing technologies for spatio-temporal data, traditional map can hardly meet the visualization requirement for this type of data. In other words, the dynamic information about spatial object or phenomenon cannot be expressed fully by traditional map. The Space-Time-Cube (STC), as a three-dimensional visualization environment, whose base represents the two-dimensional geographical space and whose height represents the temporal dimension, can simultaneously represent the spatial distribution as well as the temporal changes of spatio-temporal data. For some spatial object or phenomenon, its moving trajectory can be visualized in STC as a Space-Time-Path (STP), by which the speed and state of motion can be clearly reflected. Noticeably, the problem of visual clutter about STP is inevitably due to the complexity of three-dimensional visualization. In order to reduce the impact of visual clutter, this paper discusses different aspects about visualization representation of STP in the STC. The multiple scales representation and the multiple views display can promote interactive experience of users, and the application of different visual variables can help to represent different kinds of attribute information of STP. With the visualization of STP, spatio-temporal changes and attributive characters of spatial object or phenomenon can be represented and analysed.