Advances in Science and Technology-Research Journal最新文献

{"title":"Comparative Investigation of Yield and Quality of Carbon Nanotubes by Catalytic Conversion of Recycled Polypropylene and Polyethylene Plastics over Fe-Co-Mo/CaCO<sub>3</sub> Based on Chemical Vapour Deposition","authors":"Matthew Adah Onu, Olusola Olaitan Ayeleru, Bilainu Oboirien, Peter Apata Olubambi","doi":"10.12913/22998624/169133","DOIUrl":"https://doi.org/10.12913/22998624/169133","url":null,"abstract":"Polypropylene (PP) and polyethylene (PE) plastic waste is accumulating in the environment and the oceans at an alarming rate. The current management methods, mostly landfilling and incineration, are becoming unsustainable. In this study, thermal catalytic conversion of waste PP and PE polymers into carbon nanotubes (CNTs) using a trimetallic catalyst prepared from the nitrate salts of iron, cobalt, and molybdenum supported with calcium carbonate was reported. The yield and quality of multi-walled carbon nanotubes (MWCNTs) produced were investigated. The findings showed a high graphitic value for the CNTs obtained from PP and PE, as corroborated by the d-spacing of XRD. The I D /I G ratio of CNTs synthesized from PP and PE as carbon sources were 0.6724 and 0.9028, respectively, which showed that CNT produced from PP has more ordered graphite. The functional groups present in the produced CNTs were determined via FITR analysis. The BET and Langmuir surface areas were found to be (6.834 and 70.468 m 2 /g) and (6.733 and 70.347 m 2 /g) for CNTs obtained from PP and PE respectively. The d-spacing was computed as 0.3425 nm and 0.3442 nm for CNTs made from PP and PE. These fall within the graphite’s d-spacing at 0.335 nm. The TGA showed high percentage purity of 94.71 and 94.40% for the products obtained from PP and PE, respectively. The findings showed that recycled PP and PE could be good alternative carbon sources for CNT production.","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":"135619165","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":"Estimating the Size of a Crater after an Underwater Explosion","authors":"Radosław Kiciński","doi":"10.12913/22998624/171503","DOIUrl":"https://doi.org/10.12913/22998624/171503","url":null,"abstract":"There have been terrorist attacks in the Baltic region that used explosives to destroy underwater infrastructure, including the Nord Stream 1 and 2 gas pipelines. Data from the Danish National Seismic Network indicate that two explosions occurred on 26 Sept 2022, causing gas leaks from pipelines. While examining the data from 26 Sept, two disturbing events were observed in the Baltic Sea, which caused tremors of magnitude 2.3 and 2.1 on the Richter scale. Both events had high wave energy, indicating an explosion, not an earthquake. Based on the above data, it was decided to analyze the potential effects of underwater explosions in the area of the Nord Stream gas pipelines. From the point of view of ecology, the volume of material torn up from the bottom is essential. For this purpose, empirical formulas for explosions on land were used, and then the crater’s size was estimated per the physics of the underwater explosion phenomenon. Calculations indicate that the explosion of 750 kg of TNT will raise about 20 m 3 of the bottom volume into the water column. Because of the explosion, a gas bubble will form directly at the bottom, and it will suck the sand and the impurities contained in it and particles of dead organisms, bringing them to the surface and dispersing them in the water column. These attacks pose a severe environmental and safety risk as gas leaks from pipelines can cause harmful effects on marine ecosystems and people. It also violates international law and international agreements, including the United Nations Convention on the Law of the Sea and the Convention on the Protection of the Marine Environment in the Baltic Sea Region.","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":"135619169","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":"Impact of TIG Welding Parameters on the Mechanical Properties of 6061-T6 Aluminum Alloy Joints","authors":"Salah Sabeeh Abed Al Kareem, Basma Luay Mahdi, Hiba K. Hussein","doi":"10.12913/22998624/171489","DOIUrl":"https://doi.org/10.12913/22998624/171489","url":null,"abstract":"The most common gas-shielded arc welding method is tungsten inert gas welding, which uses shielding gas to isolate the welded area. Such technique is mostly used in the industrial domain, including steel framework fabrication and installation, plumbing systems, and other building jobs. The welding method and the implementation of a suitable welding joint based on some factors that contribute to the fusion process were studied in the present research. The research investigated the specifications and efficiency of the area to be welded in terms of the thermal effect on the welding joint shape and some significant mechanical property-related factors which that were deter - mined during the welding process. In this paper, aluminum alloy sheets, AA 6061-T6, with a thickness of 3 mm, were used with a 60mm width and 80mm length. These sheets were prepared to be welded using welding currents of 90A, 95A, and 100A, welding speeds of 60mm/min, 80 mm/min, and100 mm/min, and gas flow rates of 8 l/ min, 9 l/min, and 10 l/min. The experiments were designed at three distinct levels. These levels were selected to create the L9 orthogonal array. Regression analysis, signal-to-noise ratio evaluation, and analysis of variance were carried out. The created model has enhanced accuracy by predicting the reinforced hardness found in the weld specimens, according to the regression study, which showed R2= 90.09%. In addition, it was discovered that the ideal welding parameters for a welded specimen were 100 A for welding current, 80 mm/min for welding speed, and 9 l/min for gas flow. The present research examined the shape of the thermal distribution of welded parts us - ing the engineering computer program ANSYS. The experimental results clarified the proposed approach, as they showed that the welding current is the most influential factor in the hardness of the weld using the fusion process of 90.95%, followed by the welding speed of 7.48%, while the gas flow rate of 1.52% has the least effect. The authors recommend using qualified welders to ensure optimal performance. It is anticipated that these findings will serve as a foundation for analysis to optimize welding processes and reduce welding defects.","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":"135618914","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":"Compressor Heat Pump Model Based on Refrigerant Enthalpy and Flow Rate","authors":"Paweł Marcin Obstawski, Tomasz Bakoń, Jacek Gajkowski","doi":"10.12913/22998624/170971","DOIUrl":"https://doi.org/10.12913/22998624/170971","url":null,"abstract":"This paper introduces a compressor heat pump model using flow rate and enthalpy values for the calculation of heat pump control parameters. The aim of in this article presented research work was to develop an universal model of a compressor heat pump which will enable simulation tests for compressors of any volumetric efficiency with variable operating parameters (e.g. temperature of the lower source and condensation temperature) worked with any refrigerant. An additional assumption was the possibility of conducting simulation tests continuously. The model was developed on the basis of equations describing the thermodynamic transformations taking place in the refrigeration system. The data needed for the model are the input signals of saturation and condensation tem - peratures and the refrigerant mass flow rate entered as a time series. The output signals are heating capacity, cooling capacity, power consumed by the compressor, and the temperature at the second point of the thermodynamic cycle of the refrigerant. The paper presents equations for examples of the frequently used refrigerants R410a and R290 and practical verification of the presented algorithm in the laboratory made for refrigerant R410a. A description of the laboratory stand is also included. Comparison of the capacity provided by the condenser and the coefficient of performance with the values simulated using the proposed model confirms the correctness of the applied model and its practicality. The results obtained by simulation and measurements show very good convergence. The developed model makes it possible to calculate the operational parameters of the device, e.g. such as COP and SCOP for given boundary conditions, which then enables to estimate the coverage degree of the heat load of the building by the heat pump due to central heating and to estimate momentary and seasonal operating costs of the heat pump.","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":"135619150","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":"Industrial Application of Surface Crack Detection in Sheet Metal Stamping Using Shift-and-Add Speckle Imaging","authors":"Sławomir Świłło, Robert Cacko","doi":"10.12913/22998624/171811","DOIUrl":"https://doi.org/10.12913/22998624/171811","url":null,"abstract":"The sheet metal surface crack detection during manufacturing is an essential issue because of both the product quality and process productivity. Development of solutions to eliminate defective products during the metal forming process is crucial for the smooth production and for developing an appropriate tool geometry in the initial phase of the process. Currently, the methods of surface crack detection used in the industry are mostly related to visual inspection. These are methods that require operators of industrial facilities considerable attention and effort to capture emerging discontinuities on the sheet metal surface. Also, this situation results increase in the duration of the specific operations of stamping and significantly reduces productivity. Therefore, an industrial application of a non-contact laser technique that simultaneously provides the results of the speckle imaging is presented. The authors demonstrate a specially designed machine vision system along with experimental tools for the stamping operation. Proposed solution uses the phenomenon of speckle pattern that appears in the image of the investigated sheet surface produced by the laser beam emission. In this method, coherent laser light is emitted to the surface, where a speckle pattern is generated due to scatter reflection from the sheet metal surface and then, shift-and-add technique and image processing is applied. The proposed measurement technique consists, initially, of making a sequence of images of the tested object for the moving surface of the sheet. Secondly, the object’s displacement quantity in each image is determined, and the position is corrected. The test object in each image is moved to the starting position, and all images are superimposed. It allows to obtain a high-quality image with visible surface defects. Finally, the dynamically changing speckle pattern intensity is evaluated using Gaussian-of-Laplacian edge detection to investigate a surface crack location due to the surface discontinues and light scattering. This process is recommended for machine vision imaging of distant objects, which works well in industrial conditions as well as online analysis. Also, from the speckle size measurement, an experimental procedure is employed to verify the best condition for vision system resolution.","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":"135619170","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":"Numerical Analysis of Lamb Wave Propagation in Composite Plate with Different Fiber Orientation Angles – Acoustic Emission Approach","authors":"Jakub Rzeczkowski","doi":"10.12913/22998624/171452","DOIUrl":"https://doi.org/10.12913/22998624/171452","url":null,"abstract":"This paper aims at numerical finite element (FEM) research of guided Lamb waves propagation in multidirectional composite plates. All simulations were conducted in the Abaqus/CAE software by using the dynamic/explicit solver. The material considered in this work was carbon/epoxy composite laminate with [90⁰/ θ / θ / θ /- θ /- θ /- θ /90⁰] stacking sequence where θ set was equal 0⁰, 30⁰, 45⁰, 60⁰ and 90⁰. The main goal of the analysis was to evaluate the influence of fiber orientation angles θ on propagation behavior of the separate symmetric S 0 and asymmetric A 0 Lamb wave modes. Numerical model was created by using the C3D8R brick element. The Lamb waves were generated by using concentrated force with 200 kHz frequency. The acoustic signal generated by travelling wave was registered at two nodes that representthe acoustic emission sensors. Obtained results were presented in tabular form where separate mode velocities were collected and on the normalized displacement versus time plots depicted registered wave sig - nals. In addition, the contour diagrams and through-thickness deformations plots were created to present behavior of the extensional and the flexural modes. The greatest value of the S 0 mode velocity was obtained for unidirectional laminates whereas the lowest for composite plate with 45⁰ fiber orientation angle. The asymmetric mode found to generate slightly greater deformation of plate in XZ plane than the symmetric. Recognition of the Lamb wave behav - ior in multidirectional laminates will allow to better planning the experimental acoustic emission tests.","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":"135618920","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 the Potential for Reducing the Energy Consumption of a Vegetable Sprouts Production Using Flownex Simulation Software","authors":"Klaudia Słomczyńska, Paweł Mirek, Marcin Panowski","doi":"10.12913/22998624/170944","DOIUrl":"https://doi.org/10.12913/22998624/170944","url":null,"abstract":"Using the waste energy generated in any production process is the one of possible ways of increasing energy effi - ciency. In the industrial cultivation of vegetable sprouts for food purposes, significant amounts of low-temperature waste heat are released, the source of which is the metabolic processes taking place inside the seeds. In typical installations, this energy is lost to the environment, while it could be utilised, for example, to heating the water used to irrigate the plants. This paper presents a concept of utilizing waste heat generated during the germination process of seeds using plate heat exchangers and the analysis of the potential for reducing the energy consumption of installations for vegetable sprout production. For this purpose, transient simulations were conducted using a developed simulation model of the technological line in Flownex Simulation Environment. In order to formulate a reliable simulation model, relevant device parameters and process data were collected. After building the model and calibrating it appropriately, an analysis of the variability of the values of all process parameters was performed, and the potential for recovering waste heat was determined. The results obtained from numerical modelling were verified against the results obtained from the production line and shows, that the amount of recoverable waste heat in the entire production cycle was about 5 GJ.","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":"135619153","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":"The Influence of Conditioning on Dynamic Behaviour of Polymer Composites","authors":"Marek Borowiec, Robert Szczepaniak, José Machado","doi":"10.12913/22998624/171492","DOIUrl":"https://doi.org/10.12913/22998624/171492","url":null,"abstract":"The aim of this study is to determine the effect of environmental factors in the form of UV radiation and temperature on the amplitude-frequency behaviour of polymer composites (prepregs) based on a frame - work of thermosetting epoxy resin reinforced with high-strength R-glass fibres. Two series of composites with different fibre arrangements were prepared. The series had fibres arranged at angles of 30°, 45°, and 60°, at symmetric and asymmetric orientations in relation to the central layer. The composites were subjected to conditioning which simulated a six-month period of use in the spring and summer in the temperate warm transitional climate of Central and Eastern Europe. An UV QUV/SPRAY/RP accelerated aging chamber manufactured by Q-Lab Corporation was used for this purpose, and UV-A 340 lamps were used to simulate daylight. In addition, varying loads caused by sudden temperature changes were simu - lated using the Thermal Shock Chamber T/60/V2 Weisstechnik. Conditioned samples were tested using a TIRAvib 50101 electromagnetic exciter in combination with an LMS Scadias III controller and Test. Lab software. The results of the tests, in the form of amplitude-frequency diagrams in resonance regions, indicated that certain changes occurred as a result of the conditioning, which is a new development in the area of material tests. The results shed light on the effects of environmental conditions on the stiffness characteristics of composites, causing dynamic nonlinearities when operating at resonant frequencies.","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":"135619162","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":"Experimental Determination of Material Boundary Conditions for Computer Simulation of Sheet Metal Deep Drawing Processes","authors":"Tomasz Miłek","doi":"10.12913/22998624/172364","DOIUrl":"https://doi.org/10.12913/22998624/172364","url":null,"abstract":"In solving technological problems related to sheet metal deep drawing with the use of computer tools, the key issue is still the correct determination and entering of boundary conditions to FEM-based software. The procedure for preparing input data for modelling such processes includes geometric data (drawing of tools and material), technological parameters along with the contact conditions between the workpiece and the tools (friction model and type of lubricant) and material properties, in which work-hardening curves are of particular importance. In typical material databases of FEM-based software and designed for computer modelling of deep drawing processes, the properties of only a small number of material grades are available, and commercial software producers charge additional fees for each additional quantity. Those properties that are already in the database are usually devoid of basic information, e.g. related to the state of the material (material after recrystallization, annealing, cold working has different properties). In paper, experimental tests were carried out to determine flow curves based on cold tensile curves for flat samples made of EN-AW 1050A aluminium, Cu-ETP copper, CuZn37 brass and S235JRG2 steel. The investigation used a universal testing machine with a 20 kN pressing force, equipped with specialized Test & Motion software for measuring forces and displacements. It was calibrated and satisfies the metrological requirements for class 0.5. A comparative analysis of the curves determined by the analytical method was carried out. The material models obtained in the experimental tests were used in the computer simulation of the deep drawing processes of cylindrical drawpieces in the ABAQUS software. The results were experimentally verified in terms of comparing the changes in the pressing forces as a function of the displacement of the punch. The re-sults obtained in the research can be used in industrial practice for computer-aided design of cold-deep drawing processes for drawpieces of various shapes from the discussed materials.","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":"135619354","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":"Improve Single Point Incremental Forming Process Performance Using Primary Stretching Forming Process","authors":"Aqeel Sabree Bedan, Alaa Hassan Shabeeb, Emad Ali Hussein","doi":"10.12913/22998624/172907","DOIUrl":"https://doi.org/10.12913/22998624/172907","url":null,"abstract":"Incremental forming (IF) is one of the sheet metals forming technique where is a sheet formed into a final work - piece using a series of small incremental sheet deformations. In Incremental sheet metal forming process, one of the important steps is to produce the forming part with acceptable performance such as product accurate and uniform thickness distribution with a homogenous grain distribution that consider as the main challenge of incremental sheet metal forming process. This work is carried out to find the best method to control the product performance of the final parts using a new method of applying a primary stretching forming process with a hemispherical forming tool followed by single point forming SPIF. Different primary forming depth (10, 20, 30 and 40 mm) were applied to find their effect on the forming behavior of the final product and compare them to the single point forming prod - uct without using a primary forming process. The experimental results showed the improvement in microstructure by applying SPIF process after primary stretching, with grain size of 36 µm at 40 mm forming depth as compared to 52 µm when using pure SPIF, a twining effects presence in both cases. A high improvement with a minimum di - mension deviation of (6%) with respect to the forming process in single point incremental forming process without a primary forming process that result forming deviation equal to (11.6%) with respect to the desired design. The thickness distribution of the final product also improved by applying the primary stretching forming process before the SPIF process reaches to (6.9%, 9.1%, 14.9% and 21.5%) at forming depth (10, 20, 30 and 40) mm, respectively.","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":"135618913","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}