Advances in Science and Technology-Research Journal最新文献

{"title":"Investigation of a Shock Freezing Concept with Additional Electromagnetic Field Exposure","authors":"Viktors Mironovs, Vadims Sokolovs, Vjačeslavs Zemchenkovs, Jekaterina Kuzmina, Viktorija Stankevica, Vjaceslavs Lapkovskis","doi":"10.4028/p-dlyu4l","DOIUrl":"https://doi.org/10.4028/p-dlyu4l","url":null,"abstract":"Widely used to preserve foods for long-term preservation, freezing is a standard method of preserving food goods. This technique is highly energy-intensive and time-consuming. Utilising shock freezing techniques helps to accelerate the process. The current paper analyses information regarding the technology and application of shock-freezing technologies, including those utilising electromagnetic and electric fields. The results of experiments conducted using a refrigerator equipped with an electromagnetic system are reported. In order to achieve the research objectives, coils were installed in the refrigerator to induce an alternating electromagnetic field with an electromagnetic induction value of up to 0.6 mT. Preliminary experiments were carried out using sodium chloride solutions with various concentrations found in perspective frozen food products.","PeriodicalId":46357,"journal":{"name":"Advances in Science and Technology-Research Journal","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2023-11-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135136548","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Utilization of Levoglucosan Production By-Products","authors":"Kalvis Liepins, Aivars Zhurinsh, Galina Dobele","doi":"10.4028/p-fcpqb9","DOIUrl":"https://doi.org/10.4028/p-fcpqb9","url":null,"abstract":"Biorecycling of wood includes many different processes aimed at the complete utilization of the main and by-products. The complete isolation of C5 and C6 sugars from wood and their further use is currently attracting attention worldwide. The C5 sugars can be catalytically converted directly into furfural or into monosaccharides’ aqueous solution for further hydrolytic treatment. The resulting lignocellulose can be used in thermochemical pyrolysis (350-400°C) for the synthesis of levoglucosan. The biochar formed during pyrolysis and the liquid residue after the isolation of levoglucosan are by-products and can be used as precursors to obtain valuable products – activated carbon composites for supercapacitor electrodes and catalysts in fuel cells.","PeriodicalId":46357,"journal":{"name":"Advances in Science and Technology-Research Journal","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2023-11-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135136805","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Literature Review of Applicable Ballistic Materials for Temporary Wooden Building Envelopes","authors":"Elina Barone, Baiba Gaujena, Martins Vilnitis","doi":"10.4028/p-9j2ire","DOIUrl":"https://doi.org/10.4028/p-9j2ire","url":null,"abstract":"Human security remains a topical issue, especially on the country borders where temporary houses are often used. Optimally, people should be provided with ordinary, habitable, easy-to-build, possibly portable buildings and ballistically protected. However, there is a lack of studies addressing ballistic building materials for the walls. In the scope of this study, ten ballistic materials: sand walls, concrete, steel plates, ceramic, glass fibreboards, wood (plywood, cross-laminated timber), ultra-high molecular weight polyethylene (UHMWPE) boards, aramid boards, carbon fibre boards, and gypsum plasterboard are reviewed, and their wall constructions are compared. This paper aimed to analyse bulletproof materials and to nominate the best bulletproof walls according to three required aspects - price, thermal transmittance, and weight. This is a review article that could help stakeholders to choose the appropriate ballistic material for high-risk applications.","PeriodicalId":46357,"journal":{"name":"Advances in Science and Technology-Research Journal","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2023-11-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135136549","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Manufacturing of Bioactive Biodegradable Scaffolds by Stereolithography","authors":"Viktorya Rstakyan, Liana Mkhitaryan, Mikayel Torosyan, Zaruhi Karabekian, Gohar Sevoyan, Marina Aghayan, Miguel A. Rodríguez","doi":"10.4028/p-ily5jt","DOIUrl":"https://doi.org/10.4028/p-ily5jt","url":null,"abstract":"In this study, we used Stereolithography to develop tricalcium phosphate-based scaffolds. The feedstock for the process consisted of a UV-curable resin, synthetic tricalcium phosphate, and silicon oxide. The viscosity and curability of the resins are carefully controlled to enable the fabrication of complex-shaped scaffolds. Following stereolithography, the ceramic-resin scaffolds were heat treated. The first step was debinding process followed by a sintering step. The resulting sintered samples underwent microstructure, chemical, and mechanical analysis to assess their properties. The optimized samples were then subjected to biodegradability and cytotoxicity tests to evaluate their suitability for use as tissue engineering scaffolds.","PeriodicalId":46357,"journal":{"name":"Advances in Science and Technology-Research Journal","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2023-11-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135136965","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Development of a Performance-Based Specification Model of Combat Clothing for the Procurement Process in Estonia","authors":"Ada Traumann, Merje Beilmann, Teele Peets, Allan Keefe, Piret Saartok","doi":"10.4028/p-cbrg1j","DOIUrl":"https://doi.org/10.4028/p-cbrg1j","url":null,"abstract":"The topic of the research article is the development of an evaluation method of an ergonomic-based test battery to evaluate the ease of use, cutting solution and materials of the combat clothing uniform of defence forces, which can be added to the procurement sample evaluation system. Evaluation of the ergonomics of the new combat clothing uniform was performed using military recruits who completed a Military Pentathlon test battery in outdoor conditions with eight different obstacles. The comfort and fit of the tested clothes were evaluated using observation and questionnaire. This process was carried out using 47 military personnel of the Estonia Defence Force battalions. Each soldier was measured manually with a tape measure to clarify clothing size and to characterize the test population. From the measurement results, test persons 14, whose measurements corresponded to the size number and height of the two sample combat clothing, were selected. With selected 14 test persons was performed testing of combat clothing outside, which were carried out on the test battery of ergonomic. Their performance evaluated by two external observers with relevant education. After completing the test battery, both, test subjects and observers individually filled the closed-ended questionnaire with a 3-point attitude scale with emoticons about the ergonomic aspects of the combat clothing. The analysis of the answers to the questionnaire showed that the opinions of both the subjects and the observers agreed. Among the 14 subjects, 11 were conscripts. This shows that if a corresponding test track has been prepared for testing the ergonomics of clothing, then giving an assessment to the clothing is understandable to the respondent. The method also facilitates the verification of clothing criteria as performance-based procurement assessment. Not a separate test battery was prepared during this study. This helps to save costs, as it does not require the construction of a specific test battery and is available to many military recruits.","PeriodicalId":46357,"journal":{"name":"Advances in Science and Technology-Research Journal","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2023-11-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135136958","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Analysis of Pine Resin Properties as a Way to Understand and Prevent Exudation from Wood Material","authors":"Errj Sansonetti, Dace Cirule, Edgars Kuka, Kristine Meile","doi":"10.4028/p-l0uodz","DOIUrl":"https://doi.org/10.4028/p-l0uodz","url":null,"abstract":"A major function of resin is to provide defense against external attacks by releasing the resin flow on the attacked or damaged area. Nonetheless, the leakage of the resin on the surface can have a negative aesthetic and economic impact on wood material. The aim of this study is to investigate which treatments affect the chemo-physical properties of the resin in order to hinder the exudation on wood surface during service. To achieve a thickening of the resin, it is necessary to remove the volatile turpentine, and several studies have been carried out in this direction, providing useful information about this process. The heat treatment at different temperatures, 60°C, 100°C and 150°C, respectively, gives different mass losses, thus confirming that the turpentine can remain for long time in the resin, and the changes in structural, morphological, and chemical properties are affected by the temperature. FTIR spectroscopy, before and after thermal treatment, does not show major changes in chemical structures. However, from the samples analyzed with UHPLC-DAD-MS significant differences of the ratios of 20 compounds were observed, which characterize possible chemical reactions, such as decomposition, dehydrogenation, oxidation and isomerization. After heat treatment, the glass transition temperature of resin increased. Color changes are evident: resin becomes darker with increasing the temperature of treatment, apart from the resin heated at 100°C. The chemical changes in the composition of the resin caused by heat treatment need further investigation.","PeriodicalId":46357,"journal":{"name":"Advances in Science and Technology-Research Journal","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2023-11-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135138361","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"A Promising Approach to Solid-State Hydrogen Storage: Mechanical Nanostructuring Synthesis of Magnesium by High Pressure Torsion Extrusion","authors":"Babak Omranpour Shahreza, Fjodor Sergejev, Julia Ivanisenko, Jacques Huot","doi":"10.4028/p-4ccboq","DOIUrl":"https://doi.org/10.4028/p-4ccboq","url":null,"abstract":"This article presents an investigation into the impact of High Pressure Torsion Extrusion (HPTE) on the microstructural features, hardness and hydrogen storage, focusing on pure magnesium. HPTE is a modern mechanical nanostructuring technique that can refine the microstructural properties and subsequently affects the mechanical and functional properties of the materials. Two HPTE regimes were used in this study: (1) Direct Extrusion without rotation (DE), and (2) an extrusion speed of 6 mm/min along with a rotational speed of 1.8 rpm (v6w1.8). One sample in as-received conditions was also tested as a reference. Results showed increased hardness in the material after HPTE processing, with the DE sample reaching 60 HRB and the v6w1.8 sample exhibiting a gradient distribution of hardness from 71 to 83 HRB. X-ray diffraction analysis revealed significant microstructural refinement in the v6w1.8 sample. Results of hydrogenation kinetics showed that the DE sample absorbed up to 1.2 wt.% of hydrogen, while the v6w1.8 sample displayed 7.2 wt.% of hydrogen absorption, approaching the theoretical hydrogen storage capacity for magnesium (7.6 wt.%). These findings highlight the positive effects of HPTE on microstructural refinement and hydrogen storage, showcasing its potential for advancements in materials science and hydrogen-based energy technologies.","PeriodicalId":46357,"journal":{"name":"Advances in Science and Technology-Research Journal","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2023-11-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135138368","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Results of Mathematical Modeling of Evaporation Process the Drops of Sulfuric Acid in the Gas Flow","authors":"Uliana Khimka, Andriy Helesh, Roksoliana Bukliv, Mariusz Śniadkowski","doi":"10.12913/22998624/170995","DOIUrl":"https://doi.org/10.12913/22998624/170995","url":null,"abstract":"The processes of concentration of dilute solutions of sulfuric acid (H 2 SO 4 ), in particular hydrolytic sulfuric acid for the production of pigment titanium (IV) oxide, were analyzed. It is proposed to concentrate solutions of Н 2 SO 4 by evaporation in direct contact of acid droplets with hot industrial exhaust gases. The mathematical model of the evap-oration of Н 2 SO 4 drops in a hot gas stream, which used for the calculations, makes it possible to calculate the mass, temperature, velocity, and coordinates of the drop at any time with sufficient accuracy. However, the calculations are difficult, cumbersome and require multiple processing of large data sets. Therefore, the aim of the article was to approximate the calculated technological parameters of sulfuric acid droplet evaporation by obtaining simple mathematical dependencies. The mathematical dependences of the mass transfer coefficient and the distance traveled by a drop of Н 2 SO 4 during evaporation on air temperature and drop diameter were obtained. It has been established that technologically expedient evaporation of Н 2 SO 4 drops with a diameter of ≤ 0.5·10 -3 m in traditional devices leads to significant droplet loss, increased corrosion of equipment, etc. So, in order to practically implement the technol - ogy of evaporation of HSA solutions with industrial exhaust gases, it is necessary to change the technological mode of operation of the evaporator and the design of the main device. It is proposed to use the obtained results to study the methods of intensification of the evaporation process, selecting a modern mass transfer apparatus, developing a technology for utilizing hydrolytic sulfuric acid and producing pigment titanium (IV) oxide.","PeriodicalId":46357,"journal":{"name":"Advances in Science and Technology-Research Journal","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2023-10-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135618918","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Microstructure and Mechanical Properties of AISI 1106 /AISI 1045 Steels Drawn Arc Stud Welded Joints","authors":"Samer Jasim Mahmood Algodi, Abdulhakeem Amer Salman, Ali H. Al-helli","doi":"10.12913/22998624/171020","DOIUrl":"https://doi.org/10.12913/22998624/171020","url":null,"abstract":"","PeriodicalId":46357,"journal":{"name":"Advances in Science and Technology-Research Journal","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2023-10-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135619356","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"A New Effective Algorithm for Mechanical Assembly Sequence Planning","authors":"Michał Sąsiadek, Maciej Niedziela, Waldemar Woźniak, Tomasz Jachowicz, Nikoleta Mikušová","doi":"10.12913/22998624/171271","DOIUrl":"https://doi.org/10.12913/22998624/171271","url":null,"abstract":"This paper presents a new approach for searching the most favourable mechanical assembly sequence. The proposed method is described and its basic modules are presented. The concept is based on the assumption that the method should help the engineer in specifying the best assembly sequence with the short possible time calculation, taking into account the principles of design for assembly at an early stage of development of the product design. The algorithm for generating an accurate assembly sequence was described in detail and its application on real-life example was presented.","PeriodicalId":46357,"journal":{"name":"Advances in Science and Technology-Research Journal","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2023-10-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135619158","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}