bluuebunny/crossref_metadata_2025_split huggingface dataset:
Development of a thermal-radiation single-drum roll dryer for concentrated food stuff
Authors: Cherevko Oleksander , Mikhaylov Valeriy , Zahorulko Andrii , Zagorulko Aleksey , Gordienko Irina 
Published: March 2021

The design of a thermal-radiation single-drum roll dryer with a combined method of heat supply, application and cutting of the dried layer of raw materials was developed. The dryer allows obtaining a powder fraction of a semi-finished product with a solids content of 3...5 %. Such a design solution will make it possible to obtain a high-quality semi-finished product due to low-temperature drying.
The effective viscosity of the studied pastes produced by blending apple, sea buckthorn, black chokeberry, beet and pumpkin purees was determined. Adding different percentages of raw materials to apple paste increases the effective viscosity by 9...18 %. According to the results of the organoleptic evaluation, the sample with the following composition turned out to be the best: apple – 30 %, sea buckthorn – 20 %, black chokeberry – 15 %, beet – 15 % and pumpkin – 20 %. The drying time of the blended paste with a solids content of 45 % at a temperature of 65 °C and different layer thicknesses of application to the working surface (8, 6 and 4 mm) is 75, 60 and 56 min, respectively.
All the samples of pastes have a reddish-purple color with a wavelength of 610.5...614.5 nm and a tone purity of 66.5...78.8 %. The wavelength of the dried fraction is 495...615.3 nm with a tone purity of 34.3...34.8 %, from bluish-red to bluish-purple. The brightness of the samples after drying decreases within 3...4 %. The obtained color change values and drying time of the samples confirm the possibility of using the improved dryer to obtain high-quality vegetable semi-finished products of the dried fraction. The experimental data will be useful in design calculations and testing of the developed dryer in order to obtain its maximum efficiency
Establishing regularities in the propagation of phase transformation front during timber thermal modification
Authors: Tsapko Yuriy , Horbachova Oleksandra , Tsapko Аleksii , Mazurchuk Serhii , Zavialov Denys , Buiskykh Nataliia 
Published: March 2021

The creation of environmentally friendly protective materials for building structures made of wood could make it possible to influence the processes of stability and the physical-chemical properties at the thermal modification of hornbeam wood over a certain time. That necessitates studying the conditions for investigating phase transformations when the timber is exposed to high temperature, as well as establishing the mechanism of hornbeam wood thermal modification. Given this, a mathematical model of the phase transformation process during the transfer of heat flux to a sample was built. Based on the derived dependences, it was established that when hornbeam wood is exposed to temperature treatment, it undergoes endothermic phase transformations characterized by the heat absorption and change in the color of hornbeam wood. In particular, at a temperature of 200 °C, the temperature in the wood decreases by 5 % due to the chemical changes in the structure of cell wall components (lignin, cellulose, and hemicellulose). It was found that the process of thermal modification is accompanied by the decomposition of hemicellulose and the amorphous part of cellulose, a decrease in moisture absorption, as well as a decrease in the volume of substances that are a medium for the development of fungi. In addition, lignin and the resulting pseudo lignin undergo a process of polymerization and redistribution throughout the cell volume. At the same time, they give the cell walls higher density, hardness, increase hydrophobicity (water repellency), thereby reducing the ability to absorb moisture and swell. It was established that the most effective parameter of phase transformations is the temperature and aging duration. The results of moisture absorption have been given; it has been found that over 6 hours of modified timber exposure, its moisture absorption decreases by more than 10 times, which allows its application at facilities with high humidity
Effect of target-substrate distance on thickness and hardness of carbon thin films on SKD11 steel using target material from battery carbon rods
Authors: Purkuncoro Aladin Eko , Soenoko Rudy , Santjojo Dionysius Joseph Djoko Herry , Irawan Yudy Surya 
Published: March 2021

Carbon thin films on SKD11 steel were deposited by 40 kHz frequency plasma sputtering technique using a waste of battery carbon rods in argon plasma, and their mechanical properties were investigated by various target-substrate distances (1 cm, 1.7 cm, 2 cm, and 2.4 cm). The power used is 340 watts, the vacuum time is 90 minutes, and the gas flow rate is 80 ml/minute. The deposition time of carbon in plasma sputtering is 120 minutes with the initial temperature (temperature during vacuum) of 28 oC and the final temperature (the temperature after plasma sputtering) is 300 oC. The hardness value of SKD11 steel deposited with carbon thin films on SKD11 with target-substrate distance was tested using the Vickers microhardness test. Testing the thickness of the carbon thin films on the SKD11 steel substrate was carried out using a Nikon type 59520 optical microscope. Qualitative analysis of the thickness of the carbon thin films on the SKD11 steel substrate at a scale of 20 μm is shown by an optical microscope. Qualitatively, the thin film at a distance of 1.7 cm looks the brightest and thickest than other distance variations. Based on the Vickers microhardness test and Nikon type 59520 optical microscope, at the distance of 1 cm to 1.7 cm, the average thickness and hardness increased from 10,724 μm (286.6 HV) to 13,332 μm (335.9 HV). Furthermore, at the variation of the distance from 1.7 cm to 2.4 cm, the average thickness and hardness continued to decrease from 13.332 μm (335.9 HV) to 7.257 μm (257.3 HV). The possibility of interrupting atoms colliding with argon atoms in inert conditions increases at a long distance, thus causing the deposition flux on the SKD11 steel substrate to decrease
Identification of patterns of crystal-chemical transformations in historical artifacts made of metals
Authors: Indutnyi Volodymyr , Merezhko Nina , Pirkovich Kateryna , Andreiev Oleksii 
Published: March 2021

The theoretical substantiation of the process of elimination of individual chemical elements from crystal lattices of metals in the process of the crystal-chemical transformations taking place during the long history of artifact existence was given. To confirm the theoretical conclusions, five ancient gold items from different historical periods (from the IV century B.C. to the XVIII century A.D.) with approximately the same contents of gold, silver, copper, and iron in the alloy body were studied. The conducted studies will promote more exact attribution of historical artifacts made of metals and revealing the signs of forgery or restoration.
The chemical composition of items was determined immediately under patina and in the alloy body using a scanning electron microscope equipped with an energy dispersion spectrometer. The results have shown a much lower gold content inside the alloy than in the item surface. At the same time, the undamaged surface cleansed of mineral crusts contained significantly fewer impurities than the polished surface which did not have contact with the environment. Therefore, the study of the chemical composition of gold artifacts cannot be conducted solely based on surface studies.
The studies have resulted in establishing a dependence of the concentration of the main component (gold) of the alloy in the artifact surface on the item age in thousands of years. Equations for predicting the age of the items that are chemically belonging to the described item group were also presented.
Studies of peculiarities of crystal-chemical processes are very important in practice to prove the historical artifact authenticity, adjust artifact dating, identify signs of forgery or profound changes caused by restoration
Performance of perovskite solar cell coated with graphene oxide as hole transport layer
Authors: Hatib Rustan , Soeparman Sudjito , Widhiyanuriyawan Denny , Hamidi Nurkholis 
Published: March 2021

Organic metal halide perovskite has recently shown great potential for applications, as it has the advantages of low cost, excellent photoelectric properties, and high power conversion efficiency. The Hole Transport Material (HTM) is one of the most critical components in Perovskite Solar Cells (PSC). It has the function of optimizing the interface, adjusting the energy compatibility, and obtaining higher PCE. The inorganic p-type semiconductor is an alternative HTM due to its chemical stability, higher mobility, increased transparency in the visible region, and general valence band energy level (VB). Here we report the use of the Graphene Oxide (GO) layer as a Hole Transport Layer (HTL) to improve the perovskite solar cells' performance. The crystal structure and thickness of GO significantly affect the increase in solar cell efficiency. This perovskite film must show a high degree of crystallinity. The configuration of the perovskite material is FTO/NiO/GO/CH3NH3PbI3/ZnO/Ag. GO as a Hole Transport Layer can increase positively charged electrons' mobility to improve current and voltage. As a blocking layer that can prevent recombination. The GO can make the perovskite interface layer with smoother holes, and molecular uniformity occurs to reduce recombination. The method used in this study is by using spin coating. In the spin-coating process, the GO layer is coated on top of NiO with variations in the rotation of 700 rpm, 800 rpm, 900 rpm, 1,000 rpm, and 1,500 rpm. The procedure formed different thicknesses from 332.5 nm, 314.7 nm, 256.4 nm, 227.4 to 204.5 nm. The results obtained at a thickness of 227.4 nm reached the optimum efficiency, namely 15,3 %. Thus, the GO material as a Hole Transport Layer can support solar cell performance improvement by not being too thick and thin
Development of Fe-5Al-1C alloys for grinding ball
Authors: Kartikasari Ratna , Subardi Adi , Wijaya Andy Erwin 
Published: March 2021

Our object of research is to combine the properties of Mn and the advantages of Fe-Al-C to improve the performance of grinding ball materials. Three Fe-5Al-1C alloys with compositions of 15 wt% Mn (FAM15), 20 wt% Mn (FAM20), and 25 wt% Mn (FAM25) were investigated. Argon gas was used to assist the removal of dissolved oxygen and to control the formation of metal oxides during Fe-Al-Mn-C (FAMC) fabrication. Microstructure analysis was conducted using scanning electron microscopy, and the Vickers microhardness tester was used to evaluate hardness. To guarantee the Fe-5Al-1C-Mn alloy phase, X-ray diffraction (XRD) test was performed. The EDS test was carried out to show the composition at different points and to observe the presence of several phases in the FAMC alloy system. A pin-on-disc method was employed for a dry sliding wear test, and corrosion testing was performed using the three-electrode cell polarization method. With the addition of Mn, the Vickers hardness of the FAMC alloy raised from 194.4 VHN at 15 wt% to 265 VHN at 25 wt%. The tensile strength and fracture elongation values were 424.69 MPa, 27.16 % EI; 434.72 MPa, 33.6 % EI; and 485.71 MPa, 38.48 % EI for FAM15, FAM20, and FAM25, respectively. A crucial factor for increasing the performance of grinding ball is the wear mechanism. The wear rate results for FAM25 show a decline of more than 57 % compared to FAM15 due to an increase in the hard intermetallic area. The addition of Mn elements increased the corrosion resistance of the FAMC alloys; the lowest corrosion rate occurred at 25 wt% Mn content at up to 0.036 mm/yr. According to the experimental results, the FAM25 alloys have the highest mechanical and corrosion resistance of the three types of alloys. The FAMC alloy is a promising candidate for application as a material for grinding balls by optimizing the Mn content
The use of liquid chromatography method for quantitative determination of active substances in Enalapril-H tablets
Authors: Bevz Nataliia , Myhal Artem , Ivanauskas Liudas , Gorokhova Olga , Grynenko Vasyl , Zhuravel Iryna 
Published: March 2021

The aim. Combination therapy is used to treat hypertension. Strengthening the action of the ACE inhibitor enalapril is carried out in combination with the thiazide diuretic hydrochlorothiazide. On the pharmaceutical market, such combined preparations are presented by different manufacturers in various concentrations of the active ingredients of enalapril maleate and hydrochlorothiazide. Development of methods for the quantitative determination of active substances in combined drugs by liquid chromatography is topical.
Materials and methods. Shimadzu Nexera X2 LC-30AD liquid chromatograph equipped with DAD SPD-M20A diode array detector, SIL-30AC autosampler and CTO-20AC column thermostat; analytical balance - UniBloc AUW120D; pH meter - Knick type 911pH; chromatographic column ACE C18, size 250 mm × 4.6 mm, packed with octadecylsilyl silica gel for chromatography with a particle size of 5 μm.
Results. Based on the results of the work, a method for the quantitative determination of enalapril and hydrochlorothiazide in the presence of HPLC was proposed. The obtained validation characteristics indicate that the method for the quantitative determination of hydrochlorothiazide in Enalapril-H tablets corresponds to the following parameters: correctness, precision, linearity ( =0.70 ≤ max =1.60, d=0.22 ≤ maxd = 0.51, a=0.71 max a=2.60, r = 0.9997 min r=0.9981). In the quantitative determination of enalapril maleate in combined tablets, it was found that correctness, precision, linearity are performed ( =1.21 ≤ max =1.60, d=0.24 ≤ max d=0.51, a=1.35 max a=2.60, r = 0.9991 min r= 0.9981).
Conclusions. The method of quantitative chromatographic determination of enalapril maleate and hydrochlorothiazide in an antihypertensive combination drug has been improved. The proposed parameters of the chromatographic separation of the mixture in comparison with the initial ones contribute to a decrease in the costs of monitoring, a decrease in the volume of harmful emissions and cause an extension of the life of the chromatographic column
Students’ Critical Thinking Skills in Innovating Problem Solving in the Physics Entrepreneurship Course
Authors: Budi Gunarjo S , Farcis Fenno 
Published: March 2021

The 21st century physics educators are expected to have 21st century skills, one of which is having life and career skills. One of the life skills assets is professional entrepreneurship. This study aimed to 1) determine the profile of students' critical thinking skills in innovating problem-solving during physics entrepreneurship course and 2) determine students’ responses about critical thinking skills in innovating problem solving. This research conducted using preliminary research methods with data collection techniques in the form of description test instrument that filled out by students, and student questionnaires instrument. The data obtained were analyzed descriptively qualitatively. The study was conducted on 30 students of department of physics education at a university in the city of Palangkaraya. The results showed that all aspects of critical thinking skills (Facione's version) that were measured, namely the ability to interpret, analyze, evaluate, inference, explain, and self-regulation were on average in the low category (56.9%). Students gave agreed (A) to very agreed (VA) responses to the implementation of learning that applied critical thinking skills in innovating to solve problems. These results can be concluded that the students have very limited critical thinking skills in solving entrepreneurial problems, so that efforts are needed to improve students' critical thinking skills in solving entrepreneurial problems, one of which is by developing a learning model that can be applied to physics entrepreneurship course which hopefully can improve critical thinking skills of physics education students.
SIFAT TURUNAN PADA ALJABAR LIE AFFINE BERDIMENSI 6
Authors: Kurniadi Edi 
Published: March 2021

In this paper we study that any derivation of affine Lie algebra of dimension 6, denoted by , is inner. We give another approach to prove it by direct computations of transformation matrix of derivation of . We show that transformation matrix for the derivation of any element in equals to transformation matrix of adjoint representation of its element. Furthermore, we give an alternative to prove that is Frobenius Lie algebra. Keywords :Affine Lie algebra, Derivation of a Lie algebra, Frobenius Lie algebra
Validitas E-Module IPA Terintegrasi Nilai-Nilai Agama Islam pada Pokok Bahasan Energi di SMP Kelas VII
Authors: Aulianingsih Ita , Vitrianingsih Devi , Yuliani Hadma , Mardaya Mardaya 
Published: March 2021

Bahan ajar berupa e-module perlu untuk dikembangkan oleh guru dan dilakukan proses validasi. Penelitian ini bertujuan untuk mengetahui kelayakan e-module IPA terintegrasi islam pada pokok bahasan energi. Kelayakan dilihat dari hasil validasi ahli materi yang meliputi kelayakan materi, bahasa, dan penyajian materi, kelayakan dari hasil validasi ahli media memiliki indikator kelayakan huruf, desain, konsistensi, gambar, dan pengoperasian e-module. Penelitian ini berbantukan aplikasi eXe-Learning dalam penyusunannya. Penelitian ini merupakan penelitian pengembangan atau biasa dikenal dengan istilah Research and Development (R&D) dengan menggunakan model penelitian 3D (define, design,develop). Instrumen yang digunakan dalam pengumpulan informasi dan data adalah dengan menggunakan angket lembar validasi oleh ahli materi dan ahli media. Pada penelitian ini analisis yang digunakan adalah analisis deskriptif kualitatif. Validator kelayakan e-module terdiri dari dua orang ahli materi dan dua orang ahli media. Hasil penelitian menunjukan uji validasi kelayakan oleh ahli media dari pengemangan e-module IPA terintegrasi islam ini mendapat persentase sebesar 93% dengan kategori nilai validitas sangat layak, dan hasil validasi ahli materi dari pengembangan e-module IPA terintegrasi islam mendapat persentase sebesar 70% dengan kategori nilai validitas layak. implementasi dari validasi e-module ini yaitu dapat digunakan di sekolah-sekolah yang masih kurang dalam ketersediaan bahan ajar.Teaching materials in the form of e-modules need to be developed by the teacher, and a validation process is carried out. The research aims to know the feasibility of an Islamic integrated science module on energy subjects. Worthiness is seen from the validation of materials that include material worthiness, language, and material presentation, the worthiness of the validation of media experts, has the feasibility of letters, designs, consistency, images, and operation of the e-module. The study proclaims an exe-learning application during its compilation. This study is a development or commonly known research and development (R&D) study using 3D research models (define, design, develop). The instrument used in information and data collection uses a validation sheet by materials expert and media expert. In the study, the analysis used is qualitative descriptive analysis. The validator of the feasibility of the e-module consisted of two materials experts and two media specialists. Research shows the feasibility validation test by media experts on the application of the Islamic IPA e-module gets a percentage of 93% with its validating value category well deserved, and the results of the mathematicians from the development of the Islamic integrated science e-module get a percentage of 70% with the validity value category feasible. The implementation of the validation of the e-module could be used in schools that are still less available for teaching.
Analisis Kebutuhan Pengembangan Media E- Learning Berbasis Telegram Pada Pokok Bahasan Hukum Newton di SMP
Authors: Al-Furqansyah Yuan Akhmad , Yuliani Hadma , Syar N I 
Published: March 2021

Penelitian ini bertujuan untuk 1) mengetahui kendala yang dialami siswa dalam memahami materi fisika pada saat pandemi Covid-19; 2) mengidentifikasi media pembelajaran yang digunakan guru dalam proses pembelajaran di kelas; 3) menganalisis media pembelajaran yang perlu dikembangkan dalam proses pembelajaran fisika; 4) mendeskripsikan analisis kebutuhan pengembangan media e-learning berbasis telegram materi hukum Newton di SMP. Jenis penelitian ini adalah penelitian dan pengembangan (R&D) dengan menggunakan 3D dibatasi pada tahap define. Metode pengumpulan informasi dan data yang digunakan yaitu memberikan angket online kepada siswa kelas VIII dan IX di SMPN 11 Palangka raya. Teknik analisis yang digunakan adalah deskriptif kualitatif. Hasil penelitian menunjukkan bahwa 1) terdapat kendala yang dialami siswa dalam memahami materi akibat sistem pembelajaran online yang dilakukan pada saat pandemi Covid-19; 2) media pembelajaran yang digunakan dalam proses pembelajaran meliputi:LMS google classroom dan PDF; 3) Software e-learning perlu dikembangkan dalam pembelajaran fisika khususnya pada materi hukum Newton untuk membantu dalam memahami materi; dan 4) Sebanyak 63,8% siswa yang menggunakan media e-learning menjadikan pembelajaran lebih menyenangkan dan 80,9% siswa menyatakan e-learning berbasis Telegram membantu memahami materi fisik This study aims to 1) find out the obstacles experienced by students in understanding physics material during the Covid-19 pandemic; 2) identifying the learning media used by the teacher in the learning process in the classroom; 3) analyzing the learning media that need to be developed in the physics learning process; 4) describe the analysis of the needs for the development of media e-learning based on telegrams, Newton's law material in junior high school. This type of research is research and development (R&D) using 3D limited to the stage define. The method of collecting information and data was giving online questionnaires to students in grades VIII and IX at SMPN 11 Palangka Raya. The analysis technique used is descriptive qualitative. The results showed that 1) students experienced obstacles in understanding the material due to the online learning system during the Covid-19 pandemic. 2) the learning media used in the learning process include LMS, google classroom and PDF. 3)software E-learning needs to be developed in physics learning, especially in Newton's law material, to understand the material. 4) As many as 63.8% of students who use media e-learning make learning more fun, and 80.9% of students state that -e-learning Telegrambasedhelps them understand physics material.