bluuebunny/crossref_metadata_2025 huggingface dataset:
Intermolecular Interactions Studies of ZnO-Tryptophan Suspension
Authors: Alameen A S , Yaseen S A , Saif F A , Undre S B , Undre P B
Published: October 2020

The physicochemical properties (PCPs) have been studied to demonstrate the intermolecular interactions of ZnO nanoparticles (NPs) suspension. Tryptophan (Tryp) was dissolved in water and used as dilute solution to study the dispersion of ZnO NPs in different concentrations (25 to 150 uM) with 25 step. Density p, apparent molar volume V®, refractive index (RI) nD and speed of light c have been reported. Man Singh equations were used to calculate the viscosity tj, surface tension y and friccohesity a, activation energy Ay*2
was calculated using Arrhenius equation on the basis of pendant drop number (PDN) and viscous flow time (VFT) which counted by Borosil ManSingh Survismeter (BMS) instrument for solutions at room temperature. The physicochemical properties revealed the effect of ZnO NPs concentration on intermolecular interactions in dispersion systems. The results depicted the strong role of Tryptophan on ZnO NPs dispersion process in the term of solute-solvent and solute-solute interactions and free chemical reaction suspension.
Rotational Temperature of AlO Molecule from Fourier Transform Spectrum of the 0-1 band of B2∑+ - X2∑+ System
Authors: Londhe C. T. , Undre P. B.
Published: October 2020

Rotational structure of (0-1) bands of the B2∑+ - X2∑+ system of AlO molecule was recorded on Fourier Transform Spectrometer. Intensity distribution among the well-resolved rotational lines of R1 and R2 for each band was recorded and average rotational temperature calculated from these lines which is 1813 K.
Integrating environmental understanding into freshwater floatovoltaic deployment using an effects hierarchy and decision trees
Authors: Armstrong Alona , Page Trevor , Thackeray Stephen J , Hernandez Rebecca R , Jones Ian D
Published: October 2020

In an era of looming land scarcity and environmental degradation, the development of low carbon energy systems without adverse impacts on land and land-based resources is a global challenge. ‘Floatovoltaic’ energy systems—comprising floating photovoltaic (PV) panels over water—are an appealing source of low carbon energy as they spare land for other uses and attain greater electricity outputs compared to land-based systems. However, to date little is understood of the impacts of floatovoltaics on the hosting water body. Anticipating changes to water body processes, properties and services owing to floatovoltaic deployment represents a critical knowledge gap that may result in poor societal choices and water body governance. Here, we developed a theoretically-derived hierarchical effects framework for the assessment of floatovoltaic impacts on freshwater water bodies, emphasising ecological interactions. We describe how the presence of floatovoltaic systems may dramatically alter the air-water interface, with subsequent implications for surface meteorology, air-water fluxes and physical, chemical and biological properties of the recipient water body. We apply knowledge from this framework to delineate three response typologies—‘magnitude’, those for which the direction and magnitude of effect can be predicted; ‘direction’, those for which only the direction of effect can be predicted; and ‘uncertain’, those for which the response cannot be predicted—characterised by the relative importance of levels in the effects hierarchy. Illustrative decision trees are developed for an example water body response within each typology, specifically, evaporative water loss, cyanobacterial biomass, and phosphorus release from bed sediments, and implications for ecosystem services, including climate regulation, are discussed. Finally, the potential to use the new understanding of likely ecosystem perturbations to direct floatovoltaic design innovations and identify future research priorities is outlined, showcasing how inter-sectoral collaboration and environmental science can inform and optimise this low carbon, land-sparing renewable energy for ecosystem gains.
Diversity of Medicinal Plants in Yard in Several Villages in Indonesia
Authors: Rahayu M , Ibo L K , Arimukti S D , Susiarti S
Published: October 2020

In Indonesia, yard or home garden as one of the processed land has not received full attention. One of the roles of the yard is as a “living pharmacy”. Research and inventory of plants grown in the yard of 11 villages in Indonesia recorded no less than 120 plant species were used as medicinal herbs. Some were also used as traditional cosmetics and spices. Zingiberaceae family are the most commonly used and cultivated plants. Information on the results of this ethnobotany research is expected to provide input to improve yard development.
Effect of fermented feed supplementation in circulated aquaponic system with catfish (Clarias sp.) on growth of lettuce (Lactuca sativa L.)
Authors: Handayani R , Dinoto A
Published: October 2020

Aquaponic systems of aquatic animal-plant are a model for conversion of waste into plant substrates and its efficacy is estimated depending on the type of feed given. This study aims to investigate the effect of fermented feed in the circulating aquaponics system with catfish (Clarias sp.) on the growth of lettuce (Lactuca sativa L.). The study was carried out in a circulated serial aquaculture tanks containing catfish. Various inputs of fermented fish feed was applied including low concentration (6% of fish weight) and high concentration (9% of fish weight). The growth of lettuce, water quality, and total microorganisms were measured. As results, maximum length and width of lettuce were higher in supplementation of higher feed concentrations (9%), as well as tendency height and weight of plant clumps plant.
Isolation of An Erythromycin-Resistant (Putative) Gene From Bacillus Halodurans CM1
Authors: Widamayanti  , Haniyya  , Helianti I , Abinawanto
Published: October 2020

Bacillus halodurans CM1 is one of the bacterial strains from BPPT Culture Collection which had been isolated from sediments in the Cimanggu hot spring, West Java, previously. The whole genomic DNA of this strain has not yet been deeply studied despite its potential as host to produce several kinds of useful enzymes, such as xylanase, lipase, and protease. Besides the industrial enzymes, potential genes in B. halodurans CM1, for example antibiotic-resistant genes, could be engineered later for further purposes. Earlier experiments showed that CM1 strain has the ability to survive in the media with erythromycin, suggesting there might be genes responsible for this erythromycin resistance. This study aimed to isolate erythromycin-resistant gene from B. halodurans CM1 using a PCR approach. The primers used for PCR were designed based on the GenBank database of whole genome Bacillus halodurans C-125. The PCR product was then ligated into a pGEM-T easy cloning vector, and the recombinant vector then transformed into Escherichia coli DH5a. The DNA fragment with the size of 864 bp was obtained and it encoded 288 deduced amino acids. DNA sequence analysis showed that the gene had 99% similarity with gene encoding erythromycin resistance from B. halodurans C-125 (GenBank No access: BA000004.3, ErmK). There are 3 nucleotides in the ErmK sequence of B. halodurans CM1 that are different from that of another well-known strain B. halodurans C-125. This dissimilar pattern of sequence encodes Leu instead of Ser in 155th orders of CM1 amino acid sequence.
Comprehensive test of rhizobacteria as biostimulant, vesicular arbuscular mycorhizza (VAM) and graded dose of NPK fertilizer on the growth of bok choy (Brassica rapa L.)
Authors: Widawati S , Suliasih
Published: October 2020

Collaboration test of rhizobacteria as biostimulant, vesicular arbuscular mycorhizza (VAM) and graded dose of NPK fertilizer was a preliminary experiment to re-fertilize marginal soils. The objective of this experiment was to obtain the suitable collaboration of rhizobacteria as biostimulant, VAM and NPK dose that effectively supports the productivity of the growth media (zeolite) and the growth of bok choy plants. The experiments design was RCD factorial with 2 treatments which were NPK dose (0 %, 25 %, 50 %, 75 %, and 100 %) and microbial biostimulant. Rhizobacteria acting as biostimulant used were nitrogen fixing bacteria (NFB) (Azospirillum sp., Azotobacter sp., Rhizobium radiobacter InaCCB835), phosphate solubilization bacteria (PSB) (Serratia sp., Klebsiella variicola InaCC B827, Mangrovibacter plantisponsor InaCC B841, Tolumonas osonensis InaCCB831) and VAM. Each treatment, including control, was repeated 3 times. Bok choy seeds from each treatment were planted individually on zeolite media and grown in a greenhouse for 40 days. The results showed that the treatment of MIXN1 (NFB + PSB + VAM + NPK 25%) and MIXN2 (NFB + PSB + VAM + NPK 50%) were effective collaborations of biostimulating rhizobacteria, VAM and NPK dose on supporting the fertility of growth media with the number of rhizobacteria of 107 cfu g-1 zeolite and supporting optimization of bok choy plant growth and the percentage of bok choy root colonization by VAM with a very high level of infection.
WRF Sensitivity to Simulate EMP in the Diurnal Cycle of Precipitation over the North Coast of West Java
Authors: Yulihastin E , Fauziah I R , Hadi T W
Published: October 2020

The Early Morning Precipitation (EMP) over coastal region is an uncommon pattern in the diurnal cycle due to land-see breeze regular mechanism. This phase shift of diurnal cycle could hinder a numerical weather prediction to capture precipitation. This study aims to investigate sensitivity of WRF model on simulating EMP over north coast of West Java. Some cases (26 January 2006, 4 February 2008) representing heavy precipitation have been simulated in capturing EMP over the north coast of West Java to examine model sensitivity on convection scheme and domain size. The results showed the Betts-Miller-Janjic (BMJ) scheme could simulate EMP quite well on phase, whereas the Kain-Fritsch (KF) scheme capture out of phase on diurnal cycle. For model sensitivity on domain size, the larger domain displayed more realistically in phase to simulate EMP. For synoptic condition during heavy precipitation, it appeared that Cross Equatorial Northerly Surge (CENS) which is enhanced by South China Sea-Cold Tongue (SCS-CT) played main role to develop EMP.
Flood Inundation Mapping Using Synthetic Aperture Radar Data Single Polarization: A Case Study of Flood in Lake Tempe, South Sulawesi-Indonesia
Authors: Febrianti N , Yulianto F , Arda M , Haryani N
Published: October 2020

Remote sensing data can be used to help disaster management and environmental management because this data has advantages in terms of speed, is more efficient, can reach large and remote areas. Aside from that, it has consistency in measurement, can make repeated measurements, and has measurable accuracy. Floods in Lake Tempe occur almost every year due to overflowing of Lake Tempe. This research will detect flood inundation from Sentinel-1 data with single-polarization of flooding in Lake Tempe, South Sulawesi. The data used were Sentinel-1 data before flooding (2 May 2018) and after flooding (26 May 2018). The Single polarization of the Sentinel-1 can be used very well to identify floods event. The difference of input band uses the threshold of -6, and enables smoothing of 10. Utilization of tidal junction between Lake Tempe and Lake Sidenreng for agriculture and settlement has caused flooding due to lake water overflowing in the rainy season. This single polarization method can already be used in flooded areas, although in some locations it is still overestimates.
Evaluation of planetary boundary layer schemes on weather research forecasting by using intensive observation at kototabang
Authors: Fathrio I , Lasmono F , Risyanto  , Juaeni I
Published: October 2020

This study examined Weather Research and Forecasting (WRF) simulation with different closure type of Planetary Boundary Layer (PBL) in six PBL schemes. This study aimed to evaluate the performance of PBL scheme in representing the vertical profile of the atmosphere over Kototabang. Intensive observation during boreal spring in 2002 using radiosonde and Automatic Weather Station (AWS) provided were used to verify the results of WRF. Our finding showed that most of PBL scheme successfully simulated diurnal variations of PBL, temperature and relative humidity. However, the bias in magnitude were found during the daytime. This study shows that ACM2, applying mixed local and non-local closure type, performed more realistic temperature and relative humidity profile with minimum bias compared to other schemes.
Variability and sensitivity of stability indices at Kototabang (West Sumatera, Indonesia)
Authors: Juaeni I , Risyanto  , Fathrio I , Harjana T , Trismidianto
Published: October 2020

Stability index data obtained from the Radiosonde launch at the Space and Atmospheric Observation Station Agam District (West Sumatera-Indonesia) in 30 August to 2 September 2016 (three times launches a day), 5 March to 9 March 2018 (twice launches a day) and 29 April to 2 May 2019 (once launch a day) used Vaisala RS41-SG. The purpose of this study was to investigate the stability indices variations and finding the best indicators for convective disturbances at Kototabang in the tropical region. The stability indices studied were CINH, CAPE, K-index, Ko-index, S-index, SI, LI, TT-index, and the values of temperature, pressure, and height of the stability layers (LCL, LFC, CCL, and EL). K-index, S-index, and TT-index indicated that atmospheric conditions were always unstable. The indices fluctuated slightly as well as temperatures and pressures at stability level. While CAPE, Ko-Index, LI, SI, CINH, temperature and pressure of EL, and the elevations of LCL, LFC, CCL, El were very fluctuating and showed clearly the stable and unstable conditions. Three different observation periods produced three sets of characters for each index. Based on variability analysis and two assessment derived CAPE, CINH, SI and EL-Z can be used as the rainfall predictors.
Application of Time-Series Sentinel-1A for Land Deformation in Central Aceh, Indonesia
Authors: Jefriza  , Yusoff Izham Mohamad , Abir Ismail Ahmad , Syahreza Saumi , Rusdi Muhammad , Razi Pakhrul , Lateh Habibah
Published: October 2020

Several decorrelation phenomena of Interferometric Synthetic Aperture Radar (InSAR) have led researchers to develop various multitemporal InSAR (MT-InSAR) techniques with the application of time series/stack of images. In this study, we present the land surface movement monitoring using MT-InSAR techniques in the Central of Aceh-Indonesia, and focus on the temporal and spatial pattern of uplift and subsidence by using multi InSAR methods such as Quasi-Persistent Scatterer (Q-PS) and Small Baseline Subset (SBAS). A total of 18 scenes of Sentinel-1A(S-1A) and 14 scenes of ALOS PALSAR-1(PALSAR-1) images were acquired between 2018 and 2019, as well as 2007 and 2010, where then the multitemporal methods and techniques were applied sequentially to a set of those data. The results showed that the either the S-1A and PALSAR-1 velocity subsidence at Nunang and Musara Alun villages were range from 2.4 to 5.7 and 0.6 to 2.3 mm/year, respectively which corresponded to the results obtained by other research publication. The deformation in Central Aceh needs continuous monitoring using InSAR as the place is a landslide prone area because of the nature of the terrain.
Kinetics of soursop leaves antioxidant extraction using microwave-assisted extraction
Authors: Megawati  , Fardhyanti D S , Widjanarko D , Hanifah  , Bungsu G M , Rizky M H F
Published: October 2020

The purpose of this research is to study the kinetics of soursop leaves antioxidant extraction using microwave-assisted extraction. The kinetics was approached by a homogeneous mechanism using the first and second-order rate law. The extraction was conducted with ethanol as the solvent (1:13 v/v) using a modified microwave oven operated at various powers (300, 450, and 600 W) for 2-10 minutes. The soursop leaves extraction with ethanol using microwave-assisted extraction obtained a maximum yield of 33.98% (with total phenol of 24.10 mgGAE/g extract) at 600 W and 8 minutes. The kinetics of soursop leaves antioxidant extraction can be quantitatively described by the homogeneous rate law, where the second-order model is better than the first one. The extraction capacity and constant rate increase as the microwave power does. At 300, 450, and 600 W, respectively, the extraction capacities were about 500, 588, and 667 mg/l and the constant rates were 8.5 × 10-4, 9 × 10-4, and 1.18 × 10-3 l/mg/min.
Properties of polyvinyl alcohol composite filled Ampel bamboo (Bambusa vulgaris) microfibrils fibrillated by mechanical treatment
Authors: Prasetiyo K W , Fakhruzy  , Kusumaningrum W B
Published: October 2020

Composite for food packaging is mostly made from petroleum-based synthetic polymers that require a long period to be degraded naturally. This condition encourages the study of the use of cellulose microfibrils or organic materials as fillers and reinforcement for food packaging composites to reduce the dominance of synthetic polymers. The purpose of this study was to determine the characteristics of polyvinyl alcohol composites with fibrillated cellulose microfibrils from Ampel bamboo pulp (Bambusa vulgaris), both bleached and un-bleached. Pulp from Ampel bamboo produced by the soda process was fibrillated using a disc refiner in 10, 20, and 30 times repetition variations. Microfibril concentration of 0.1 wt% dry based on the weight of the polyvinyl alcohol (PVA) matrix. Composite preparation was carried out by dissolving polyvinyl alcohol using a hot plate stirrer at 80 °C, 300 rpm for 30 minutes. The composite solution is poured in a mold measuring 20 × 16 × 0.1 cm. Morphology characteristics from microfibrils were evaluated by scanning electron microscopy (SEM). The mechanical characteristics tested with UTM Shimadzu 1 kN in accordance to ASTM D 882-75b standard. PVA composites filled with cellulose microfibrils from bleached Ampel bamboo pulp have better mechanical characteristics than composites with unbleached pulp. Mechanical treatment in various replications in the disc refiner machine can increase tensile strength, tensile modulus, and composite elongation.
Rural Livelihood Strategies in Sumatra After the Implementation of ‘ASEAN 2020 Haze Free Policy’ (Case Study: Lebung Gajah Community, Ogan Komering Ilir, South Sumatera)
Authors: Zulfah AA , Howitzerni RC , Afryansyah  , Abdurrahim AY , Ramli M , Rahiem MDH
Published: October 2020

A series of regulations to realize ‘the ASEAN Haze Free Policy in 2020’ have been made, starting from the international level to the local level, including the ban on the use of fire for traditional agricultural land clearing (sonor) that was commonly used by rural communities in Sumatra. This study analyzes the livelihood strategies of rural communities after the issuance of the policy. The data used are primary and secondary. Primary data were collected through interviews, FGDs, and field observations in June-August 2019 at the district level (Ogan Komering Ilir District), community and member of the community (household) in Lebung Gajah Village, Tulung Selapan Sub-District. On the other hand, the secondary data were conducted during January-September 2019. Analysis conducted using the Scoones’ Sustainable Livelihood Approach found that to ensure the sustainability of their livelihoods, various households in the rural community carried out strategies: (1) agriculture intensification (‘Kebun Pangan Mandiri Program’), (2) livelihood diversification (raising livestock, catching fish, building swallow houses, & becoming construction worker), and (3) activating women’s groups (household financial and business management). In implementing their strategies, they exchange their access to livelihood assets that are owned and available through social institutions and formal organizations in the village.
Simulation of Transient Liquid Phase Bonding Process and the Influence of Interlayer Thickness
Authors: Benita B. , Samuvel Prem Kumar D.S. , Pravin R. , Hynes N.Samuel Dinesh , Sujana J.Angela Jennifa
Published: October 2020

Ceramic/metal joints are possible with silid state joining techniques. Transient liquid phase bonding is a solid state joining process which is choice process. In this paper, numerical simulation of TLP bonding of ceramic/metal is done by Finite Element simulation. The finite element analysis of the TLP process provides the temperature and residual stress distribution during the bonding. Aluminium sheet as interlayer having high wettability is used. Transient thermal analysis is performed and discussed.
Study of Cutting Forces and Prediction of Surface Quality Analysis Using Neural Network Model, Support Vector Regression Model by Various Textured Tool Condition for Ti-6Al-4V Alloy
Authors: Arulkirubakaran D. , Prince R. MalkiyaRasaline , kumar R. Monish , Aravinthkumar S. , Joshva C. Andrew
Published: October 2020

To evaluate the performance of the textured tool on surface quality with three different types of the textured pattern using Wire-Cut Electrical Discharge Machining (W-EDM) on tungsten carbide cutting tools with two different groove depth dimensions 100 μm& 200μm respectively and the tools are coated with both TiN and TiAlN using Physical Vapour Deposition (PVD) technique. Surface roughness is predicted using the Support Vector Regression, multilayer Artificial Neural Network model (ANN) model. ANN training is carried out with a pure line transfer function and backpropagation algorithm. Easy off machining and good surface finish are achieved through TiAlN coated tool with linear texture along the perpendicular to chip flow direction than the tools considered for experimental and predicted conditions.
Tribological and thermogravimetric analysis of pineapple fibre reinforced epoxy composite
Authors: Mercy J Lilly , Parmar Daniel Samuel , Srivastava Shlok
Published: October 2020

Natural fibre composites are preferred for various static and dynamic applications owing to its biodegradable capacity and strength. Pineapple fibres obtained by the retting process from pineapple leaf were successfully reinforced with epoxy resin with different fibre volume percentage. The wear rate and the thermogravimetric analysis of the polymer composite were studied. It was discovered that 30% reinforcement of pineapple fibre resulted in better wear and higher glass transition temperature due to the optimal fibre volume fraction and enough wetting of the resin on the fibre.
Effect of Load and Sliding Distance on Tribological Properties of Aisi 1040 Steel by Magnetron Sputtered Ti-6Al-4V Coating
Authors: Prince R. Malkiya Rasalin , Arulkirubakaran D. , Naveen V. , Paulraj J. Allan , Raja S. Arokkia Julius
Published: October 2020

In the present study, Ti-6Al-4V-2B4C coatings are deposited using a DC magnetron sputtering system on AISI 1040 steel substrates. The composition and elemental confirmation of the coating was explored by SEM, XRD and EDS. Wear and friction tests were trained to study the influence of sliding distance and load on tribological behaviour of Ti-6Al-4V-2B4C coated AISI 1040 steel for machine elements. Wear tests were performed on coated AISI 1040 steel substrates counter to E-52100 steel balls by using a ball-on-disc wear testing apparatus under 2N and 3N normal loads at room temperature. The different sliding distances (63, 78, 94 and 110 m) has taken for wear test under room temperature and low coefficient of friction obtained for higher sliding distance and load. Ti-6Al-4V-2B4C coated AISI 1040 steel reduces the frictional coefficient from 0.65 to 0.23 and improves the wear resistance. Specific wear rate of the coating reaches the maximum value with higher sliding distance. On the outset, it is clearly showing that the formation of oxide layers of Ti-6Al-4V-2B4C coatings mainly affects its tribological characteristics.
An experimental study of drilling parameters and determination of ovality during the drilling of grade 5 titanium alloy with TiN coated carbide drill tools
Authors: Joy Nivin , Prakash S. , Harsha Guggilapu Sri , Krishnamoorthy A.
Published: October 2020

Titanium is particularly a hard to cut element. Alloys of Titanium are also regarded as hard-to-machine materials. Out of many machining operations on Titanium, drilling is treated as very important operation as it is crucial in many applications. Drilling is normally considered among the final steps of fabrication of parts and has critical economic importance. Hence it is desirable to develop an economical and feasible drilling process for Titanium alloy and improve the effectiveness of current methods since even a small mistake in the drilling operation can lead to throwing away the entire part and having to replace the entire part. On account of above facts, an experimental trial has been made to study the machining aspects during drilling of the Ti-6Al-4V alloy. The primary aim of this research paper is to study various issues in drilling holes on grade 5 Titanium alloy with Titanium Nitride (TiN) coated carbide tool. Drill bits are selected in varying diameters and drilling procedure is carried out under different feed rates and speed. The output responses measured are temperature, thrust force and torque which are analyzed and studied. Also, the hole quality is studied by measuring the Hole Ovality on a profile projector. FESEM of drill bits is carried out to analyze the pattern of wear occurred on drill bits while drilling.
Tribological Behaviour of Aluminum Metal Matrix Composites – A Review
Authors: Ashok Kumar R , Karthick K , Jayasuriya R , Aswin Kumar J , Balaji Karthik V
Published: October 2020

An examination of Aluminum Metal Matrix Composites (AMMCs) dry sliding wear activities reinforced with reinforcements along with carbides, oxides, and nitrides. However, from the analysis, the method adopted for the composite processing plays a crucial role in achieving a uniform homogeneous composition. Preparation of base metal and reinforcement powders plays a vital role in the process of powder metallurgy, improving wettability between reinforcement particles and molten base metal in liquid metallurgy is a difficult task. AMMCs wear activity is based on different test parameters. As mechanical and tribochemical are the process involved in substance removal during dry sliding wear is subdivided into groups. The loss of reinforcement from the AMMCs through sliding wear decreases the wear rate due to abrasion by three parts. The use of solid lubricant decreases wear severity through the formation of a tribolayer between the rubbing surface. Optimizing the wear intensity is through the use of suitable replacements with optimal lubricants.
Experimental and Numerical Studies of Thermal Energy Storage using Paraffin Wax Phase Change Materials
Authors: Thirumaniraj R.R. , Muninathan K. , Kumar V. Ashok , Paul B. Jerickson , Rajendran Rahul R
Published: October 2020

The main idea of this work is to design and analyze efficient storage of thermal energy using phase change material. Solar energy is a readily available and renewable source of energy. It is also a clean energy as it does not emit carbon dioxide. However maximum utilization of solar energy is not possible without the use of thermal energy storage (TES). This thermal storage system can form an integral part of solar heating system. In this work a TES tank is designed and fabricated. Paraffin wax is the phase change material used. It is encased in stainless steel balls. The high specific heat capacity of PCM is used to store latent heat which can be used any time. Temperature measurements are taken using T-type thermocouple along with indicator. Numerical analysis is done using the CFD software Ansys Fluent.

This work mainly focuses to find the solution for the mismatch of abundant solar energy available during daytime and non-availability of energy during night-time. This project work also forms a part of a wider study to explore the possibility of PCMs to store the energy during off-peak load and releases the same during peak load. In several countries, during the daytime the load will be at peak level which leads to high cost for production. Therefore, cost saving can be achieved if heat pumps can be operated during the off-peak periods to store heat for use during the peak periods.
Analysis of the non-isothermal resin impregnation process of carbon fibre reinforced composite wing spar structure
Authors: Maung Pyi Phyo , Malysheva G V , Htet Tun Lin , Drobyshev G V
Published: October 2020

This paper presents non-isothermal resin impregnation process of high-performance light weight composite wing spar structure for trainer aircrafts. The manufacturing process of the spar is simulated in PAM-RTM software. In this research developed a reliable model of resin impregnation process simulation to determine the exact infusion time and optimize the resin inlet ports for large scale aircraft structure without using the expensive trial and error experimental approches. The work reported the use of different heating temperature processes to manufacture wing spar from carbon fibre-reinforced epoxy resin matrix composite laminates by using VARI. The influence of heating temperature during the infusion stage on the resin viscosity and impregnation time was analyzed. These results indicate that a proper heating temperature during the infusion process is necessary for quality control and manufacturing time reduction. The error between theoretical simulation and experimental studies is no more than 10%.
Composites Based on Carbon Tapes with a Copper coating Based on Organic and Inorganic Matrices
Authors: Nelyub V A
Published: October 2020

The results of experimental investigations into the impregnating kinetics when using the carbon tape with copper coating according to the magnetron sputtering technology are presented. The epoxy and aluminum-boron phosphate materials are used as binders. The composites based on these binders are evaluated by characteristics of porosity, matrix content, and thermal stability. It is established that metallization insignificantly affects the thermal stability but does not make it possible to increase the impregnation rate and leads to lowering the composite porosity.
Numerical simulation of the stability of three-dimensional elastic composite structures based on the finite element method
Authors: Dimitrienko Yu I , Bogdanov I O
Published: October 2020

A numerical method for solving the problem of the stability theory of linearly elastic bodies with small deformations in a general three-dimensional formulation is considered. The problems of this class are poorly studied in contrast to the two-dimensional problems of stability theory. At the same time, classical approaches do not allow one to take into account the effect on the structural stability of various three-dimensional effects: areas of compounds, zones of defects, etc. The study formulates a variation formulation of the problem of the three-dimensional stability theory. Based on the finite element method, a numerical statement is obtained in the form of a generalized eigenvalue problem with symmetric global stiffness matrix. The application of the proposed method is demonstrated by the example of calculating the stability of a composite plate under longitudinal compression. The simulation was carried out using the SMCM software package developed at the Department of Calculus Mathematics and Mathematical Physics of Bauman Moscow State Technical University.
Universal models of the constitutive relations for transversely isotropic compressible composites with finite strains
Authors: Dimitrienko Yu I , Gubareva E A , Karimov S B , Kolzhanova D Yu
Published: October 2020

A model of a transversely isotropic compressible elastic medium with finite strains is proposed. The model belongs to the class of the so-called universal models, which are formulated in terms of energy (conjugated) pairs of stress and strain tensors - simultaneously for several types of pairs. An algorithm is proposed for calculating the constants included in the constitutive relations of this model, based on a comparative analysis of the results of calculating deformation diagrams under uniaxial loading according to this model and using the asymptotic averaging method. An example of numerical modeling for a layered composite is given.
Thermal Regulation of Space Platform Panels by Using Electric Heaters
Authors: Gorodetsky M A , Mikhaylovsky K V , Reznik S V
Published: October 2020

In orbital flight, the temperature state of spacecraft and their constituent space platforms complexly changes in time and space. The inhomogeneous temperature field of the space platform can cause shape distortion, which negatively affects the performance of targets. To equalize the temperature field of the space platform, it is proposed to use electric heaters with differentiated power distributions. The formulation of the boundary inverse heat conduction problem is presented and the specific power of the heaters necessary for uniform distribution of the temperature field of a panel of composite material is determined.
A study of physical and mechanical characteristics of polymer composite materials by ultrasonic technique
Authors: Chulkov D I , Terekhin A B , Dumansky A M
Published: October 2020

This work is concerned with the determining of physical and mechanical characteristics (dynamic elastic modulus along the direction of reinforcement, porosity, density, percentage of binder, strength) of fiberglass plastics by ultrasonic technique. The techniques, which are currently used for evaluation of the above-mentioned parameters of polymeric composite materials, are presented. The ultrasonic technique of physical and mechanical characteristics determining of glass fiber reinforced plastics for radio engineering purpose on the base of quarzitic, glass and siliceous fillers is proposed.
Comparison of low cost lasers for graphene oxide thin films reduction
Authors: Komarov I A , Struchkov N S , Polikarpova I A , Peretiyagin V G , Buyanov A D , Danilova E A , Denisenko E I , Onoprienko E A
Published: October 2020

In this work we made reduction of graphene oxide films with different low-cost lasers (near IR (1060 nm) and blue (445 nm) to investigate possibility of such films usage for flexible electronic and nanoelectronic applications. We successfully showed possibility of graphene oxide reduction with both types of laser but blue laser showed better uniformity of reduced graphene oxide film parameters including film morphology, resistance and Raman intensity ratios. We showed that reduction with near IR laser spills out into large nonuniformity of resistance with relatively high values. Thus the usability of commercially available laser facility for graphene oxide modification without adjusting control settings (on hardware and software levels) is poor. On the other hand, relatively laboratory device based on low-power blue laser showed much better usability an it’s perspective to future market of low-cost modification facilities for thin carbon-based films.
Estimation of the durability of polymer composites on a fabric basis, taking into account the influence of non-force factors
Authors: Kayumov R A , Suleymanov A M , Muhamedova I Z
Published: October 2020

We considered the problem of evaluating the durability of film-fabric material (FFCM). The models of phase deformation of a film-fabric composite material was developed which took into account nonlinear viscoelasticity, temperature changes, material aging, microdamage accumulation processes and photodestruction. We presented the composration as an inhomogeneous body. When choosing the structure of the defining relations, we used the experimental data obtained by the authors for the phases of FFCM. Based oite under considen the modification of the second Fick’s law, the kinetic law of propagation of the photodestruction parameter deep into the representative cell of FFCM was constructed. To conduct a qualitative analysis of the behavior of the composite material under study, we formulated the problem with some model constitutive relations and numerical experiments were performed.
High-speed induction heating during tensile strength testing of a composite material based on an inorganic binder at temperatures up to 1500 ° C
Authors: Klemazov K V , Yakushkin P Yu , Zabezhailov M O , Stepanov P A
Published: October 2020

High-speed induction heating was used during strength tests in an oxidizing atmosphere of a composite material based on an aluminum-chromophosphate binder. Induction heating allows heating modes close to those of aircraft operating modes, which avoids the appearance of crystalline phases such as Al(PO3)3, Cr2O3, which arise under conditions of slow heating under classical methods of strength testing at elevated temperatures.
Research of thermal control system for nanosatellite with carbon fiber reinforced plastic body
Authors: Yu Wang , Soe-Moe Zarni , Denisov O V , Denisova L V
Published: October 2020

One of the key problems in the design of nanosatellites is to provide a specified temperature range for the operation of electronic equipment. In structures of modern nanosatellites mainly used the elemental base of smartphones. To process a large amount of information, more advanced processors with high thermal power are required. The specified thermal mode of the on-board computer can be achieved using a remote heat removal system or by direct contact of the processor cover with the carbon fiber reinforced plastics (CFRP) body of the nanosatellite. Using a model of nanosatellite as an example, a thermal control system with miniature loop heat pipes and highly heat-conducting refrigerators-emitters is designed. The influence of the thermal conductivity coefficient in the reinforcement plane of the nanosatellite CFRP body on its temperature state in low Earth orbit is studied.
Optimization of the power structure of carbon-ceramic composite materials
Authors: Yu Taraskin N , Grigorieva V L
Published: October 2020

In this paper analyze of structures and materials for the heat shields of the descent vehicles is considered. In addition, the structure, manufacturing technology and characteristics of carbon-ceramic composite materials are analyzed. A basic finite-element model of a heat-shielding coating is based, and topological optimization is performed. Based on the results of optimization, the power structures of the heat-shielding coating are developed and their strength characteristics are evaluated. The general structure of the heat shield is developed including account the heat-shielding coating.
Biharmonic Problems and their Application in Engineering and Medicine
Authors: Matevossian H A , Nordo G , Sako T
Published: October 2020

In the present paper we study some properties of solutions of the Steklov and Neumann boundary value problems for the biharmonic equation. For solving these biharmonic problems with application in engineering and medicine, we need to solve boundary value problems Dirichlet and Cauchy for the Poisson equation using the scattering model. In order to select suitable solutions, we solve the Poisson equation with the corresponding boundary conditions Dirichlet and Cauchy, that is, some criterion function is minimized in the Sobolev norms. Under appropriate smoothness assumptions, these problems may be reformulated as boundary value problems for the biharmonic equation.

MSC: 35J15; 35J35; 35J40; 58J50; 58J90.
Environmental effectiveness assessment of the technology for molding products made of polymer composite materials using a reusable flexible punch
Authors: Novikov A D , Stoyanova M V , Borodulin A S
Published: October 2020

The use of composite materials in all industries has a negative impact on the environment in general and man in particular. Polymeric binders include hazardous substances, and the auxiliary components used in production are made of non-processed materials. It is possible to reduce the negative impact on the environment by using a new technology using reusable flexible punches.
Numerical simulation of the heat transfer process in the antiicing heating system for Arctic marine applications
Authors: Dimitrienko Yu I , Chibisov V Yu , Koryakov M N
Published: October 2020

In the Arctic, there is a serious problem of icing of structures, which can cause a catastrophic disruption of the functioning of the equipment necessary to maintain the life support of sea vessels and ground structures. For marine vessels, this problem is especially relevant in view of the limitations on heating systems and the mass of permissible heating equipment. The article is a continuation of work on the research and development of an electrical heating system for the air intake grilles of marine vessels. A numerical simulation of the heat transfer conditions for the design of the air intake grille with a built-in electric heating system was carried out. Some variant calculations of the numerical simulation of heat transfer processes in the system are presented — air, a streamlined structure — an air intake grill case — a heating system. A technique has been developed for selecting the optimal parameters of the electric heating system for various operating conditions of air intake grilles.
The use of fuzzy logic for the clean-up systems control for bunkers, containing bulk solids
Authors: Abramov A M , Yu Klyukin V , Kozhikin V V , Kochneva O V
Published: October 2020

The issues of eliminating the bulk solids overhanging in bunkers using pneumatic pulse devices are considered in the following article. An algorithm for automatic control of pneumatic collapse systems based on the use of fuzzy logic methods is proposed. A constructive solution for this algorithm is given, based on the assessment of the level of bulk material on the conveyor installed at the exit of the hopper. The Mamdani algorithm is used as a fuzzy inference algorithm. The fuzzy Logic Toolbox package of the MATLAB computing environment was used for modeling fuzzy systems. The use of mid-maximum and center-of-gravity methods as a defuzzification method is considered. It is demonstrated that the use of fuzzy logic makes it possible to significantly simplify the development of the control system algorithm.
Simulation of operation of a sequential hybrid drive of a haul truck with a traction battery and a bilateral DC-to-DC converter
Authors: Buzunov N V , Pirozhkov R D , Kartashov A B , Dubinkin D M , Efremenkov A B
Published: October 2020

In this article we consider one of the possible options for organizing the traction drive of a haul truck. The used scheme of the drive organization is given, and its performance is estimated by means of the drive simulation. The consideration is given to DC-to-DC converters in drives of hybrid traction systems. The conclusion is made about their influence on the efficiency of the hybrid traction drive.
Hybrid technology for the synthesis of ultrafine carbon powder material in an amorphous state
Authors: Chaika V A , Savin V V , Zherebcov I S , Boiko M E , Boiko A M
Published: October 2020

The results of using a hybrid technology for the synthesis of ultrafine carbon powder material in an amorphous state are considered. Different modes of hybrid technology are proposed, including mechanochemical synthesis in a ball mill and the process of self-propagating sustainable combustion in a natural atmosphere to produce carbon powder materials (CPM) in an amorphous state. Using X-ray diffraction methods: diffractometric, radiographic, and small-angle X-ray scattering, heterogeneities of the CPM structure were studied. Areas of structural heterogeneity having a flat shape and containing up to 10 graphene-like layers are revealed.
Stability evaluation of cutting edges in operation of composite materials for instrumental purposes based on a metal matrix
Authors: Fedotov A A , Safonova M N , Syromyatnikova A S
Published: October 2020

The authors analyzed the existing methods for assessing the stability of cutting grains in the article. The most optimal method for assessing the performance of abrasive grains was selected based on the results of the analysis. This method was used to calculate the concentration of diamond grains on the working surfaces of samples of a composite material made on the basis of bronze. The results of the studies showed that when testing the samples for friction and wear, the number of active abrasive grains and the relative solids content of natural diamond grinding powders show the stability of the cutting edges.
Processing of steel galvanizing waste using the method of melt immersion
Authors: Gel V I , Sapozhkov S B
Published: October 2020

The article describes the methods of steel galvanizing waste processing by immersion in a zinc melt, furnaces and devices for processing hard zink and drosses into usable products for zink pots, the methods for zinc extraction from waste and their use in industry. It is demonstrated that the hot-dip galvanizing wastes is a serious resource in reducing the consumption of primary zinc, what is more their use does not entail deterioration in the quality of the hot-dip zinc coating. However, not all technologies and types of equipment for processing zinc-containing waste are equally effective. It is appropriate to use vibro-deburring closed machines for processing dross (liming), and furnace with a “roof” heated for processing hard zinc, and in the latter case, according to the technology of fractional loading of reagent – aluminum scrap – processing floating aluminum-iron intermetallic compounds carnallite-cryolite fluxing agent.
Improving the design of a disintegrator for deep utilization of enrichment tailings
Authors: Golik V I , Razoryonov Y I , Efremenkov A B
Published: October 2020

The article discusses the directions of improving the design of disintegrators for activating materials and leaching metals when disposing of solid mineral raw materials using mechanochemical technology. The results of experimental extraction of metals from non-ferrous and ferrous ores, as well as coal are presented. Disintegrator designs differing in the use of physicochemical methods of increasing activity are recommended.
Development of intelligent algorithms for the continuous diagnostics and condition monitoring subsystem of the equipment as part of the process control system of a stainless steel pipe production enterprise
Authors: Grishin E S
Published: October 2020

This article describes the process of development and implementation of an integrated APCS and continuous diagnostics and equipment condition monitoring subsystems using intelligent machine-learning-based algorithms for a stainless steel pipe manufacturing enterprise with combining local automatic control systems into a single information technology the system. Briefly, the author describes the technological equipment and the production cycle, its features, as well as its change as a result of the implementation of APCS. The software tools and their structure, the interaction of elements in the system, the main tasks solved with APCS and their impact on the quality of finished products are described. A feasibility study and justification of the application of PCS for this production are carried out.
Method for predicting the composition of the protective coating in MMA
Authors: Il’yaschenko D P , Zernin E A , Sapozhkov S B , Loskutov L G
Published: October 2020

This article presents the results of experimental studies to determine the optimal coating composition for MMA. The optimization is based on the idea of multi-factor planning, which allows us to disseminate the obtained results not only on welding processes, but also related technologies.
Theoretical study of the plant residue movement along the needle of a rotating working organ
Authors: Kem A A , Shevchenko A P , Begunov M A , Koval V S , Algazin D N
Published: October 2020

The article is devoted to the identification of dependences to determine the main rational constructive and technological parameters of the proposed rotating working organ.