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PMMA Lens Arrays for Micro Concentrator Solar Cells Produced by Hot Embossing 热压成型微聚光太阳能电池用PMMA透镜阵列
U.Porto Journal of Engineering Pub Date : 2022-11-28 DOI: 10.24840/2183-6493_008.006_0012
Bruno M. C. Oliveira, Marcionilo Júnior, R. F. Santos, E. Sequeiros
{"title":"PMMA Lens Arrays for Micro Concentrator Solar Cells Produced by Hot Embossing","authors":"Bruno M. C. Oliveira, Marcionilo Júnior, R. F. Santos, E. Sequeiros","doi":"10.24840/2183-6493_008.006_0012","DOIUrl":"https://doi.org/10.24840/2183-6493_008.006_0012","url":null,"abstract":"The rising energetical needs of modern society have been increasingly pushing for the improvement in energy efficiency. Thin-film solar cell technology encompasses several types of devices whose purpose is to gather energy emitted from a luminous source and convert it into usable electrical energy for a variety of applications, particularly low-powered devices. Micro concentrator solar cells are promising devices to solve the materials availability problem and address the power conversion efficiency simultaneously. Since the energy conversion efficiency for this type of solar cell is not particularly high, it stands out to benefit greatly from using an optical concentrator element to increase the light intensity reaching the active surface. The micro-concentrator element is comprised of a micro-lens array, which can be manufactured by different technologies, such as polymer injection moulding, extrusion, or hot embossing. In this work, we explore how hot embossing can be used to inexpensively produce spherical lenses with Ø 1 mm in an array according to micro concentrator solar cell requirements. A simple compression system coupled with an infrared lamp heat chamber was used to emboss PMMA disks. Different mould insert manufacturing technologies were used and different hot embossing parameters were assessed. The process replicability of the micro-lens cavities was determined by infinite focus microscopy and optical microscopy. The most promising lens array was achieved with a mould insert produced by μ-EDM (with Ra and Rz values of 0.6 μm and 4.58 μm, respectively).","PeriodicalId":36339,"journal":{"name":"U.Porto Journal of Engineering","volume":"167 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2022-11-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"83532182","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}
引用次数: 0
Modelling and Validation of the Axial Strain Distribution in WS2 Flakes at WS2/Epoxy/PMMA Nanocomposite under Axial Load 轴向载荷作用下WS2/环氧树脂/PMMA纳米复合材料中WS2薄片轴向应变分布的建模与验证
U.Porto Journal of Engineering Pub Date : 2022-11-28 DOI: 10.24840/2183-6493_008.006_0011
T. Petrova, E. Kirilova, Rayka Vladova, B. Boyadjiev, W. Becker, P. Dineva-Vladikova
{"title":"Modelling and Validation of the Axial Strain Distribution in WS2 Flakes at WS2/Epoxy/PMMA Nanocomposite under Axial Load","authors":"T. Petrova, E. Kirilova, Rayka Vladova, B. Boyadjiev, W. Becker, P. Dineva-Vladikova","doi":"10.24840/2183-6493_008.006_0011","DOIUrl":"https://doi.org/10.24840/2183-6493_008.006_0011","url":null,"abstract":"In the present study, a two-dimensional stress-function method is applied to model the axial strain distribution in the tungsten disulfide (WS2) flake embedded in an epoxy/polymethyl methacrylate nanocomposite structure subjected to an axial tension load. The analytical model strain distribution along the flake is calculated and compared with experimental and shear-lag model literature data for monolayer flake at an external strain of 0.35% and 0.55%, as well as with results for few-layer flakes at an external strain of 0.55%. The comparison shows good agreement and confirms the applicability of our model method for describing strains in nanocomposite layered structures in the elastic region of applied loads. The presented method is not appropriate for few layers flake at an external strain of 0.55% because of the appearance of relaxation zone and the formation of wrinkles in the flake.","PeriodicalId":36339,"journal":{"name":"U.Porto Journal of Engineering","volume":"65 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2022-11-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"91369991","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}
引用次数: 0
Infrared Lock-in Thermography Tests with Optical Feedback 光学反馈红外锁定热成像测试
U.Porto Journal of Engineering Pub Date : 2022-11-28 DOI: 10.24840/2183-6493_008.006_0001
António Ramos Silva, M. Vaz, Sofia Leite, J. Mendes
{"title":"Infrared Lock-in Thermography Tests with Optical Feedback","authors":"António Ramos Silva, M. Vaz, Sofia Leite, J. Mendes","doi":"10.24840/2183-6493_008.006_0001","DOIUrl":"https://doi.org/10.24840/2183-6493_008.006_0001","url":null,"abstract":"Thermography using a period light stimulation. However, the results are highly dependent on the accuracy of the stimulation source and its dynamic response. This work aimed to evaluate the quality of a light source as a thermal stimulation and its influence on the quality of the lock-in tests performed in PMMA samples. For this purpose, it was developed an enhanced technique, feedback lock-in thermal testing (FLTT), which uses a light sensor to measure the real light stimulation. With this solution, it was possible to improve the signal-to-noise ratio of the amplitude and phase images by approximately 2.5 times. Although only one commercial stimulation source has been tested, others may present similar behavior. Thus, this technique may be considered for lock-in systems using light stimulation, as the increment of the cost is rather small.","PeriodicalId":36339,"journal":{"name":"U.Porto Journal of Engineering","volume":"46 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2022-11-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"86699976","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}
引用次数: 1
HaliTeddies
U.Porto Journal of Engineering Pub Date : 2022-09-27 DOI: 10.24840/2183-6493_008.005_0003
Alice Bessa, Anita Barbosa, J. Costa, Julia Matysik, M. Alves, Mariana Marques, Y. Manrique
{"title":"HaliTeddies","authors":"Alice Bessa, Anita Barbosa, J. Costa, Julia Matysik, M. Alves, Mariana Marques, Y. Manrique","doi":"10.24840/2183-6493_008.005_0003","DOIUrl":"https://doi.org/10.24840/2183-6493_008.005_0003","url":null,"abstract":"HaliTeddies are made of carnosic acid present in rosemary and aim to inhibit the action of halitosis causing bacteria. A need for this product was identified due to the mandatory use of facial masks because of COVID-19, which has had a negative outcome when it comes to breathe malodour. A vegan gummy bear product was selected as the best idea to satisfy this need since it is an appealing approach for a younger audience of 15- to 49-year-olds. The strategy for production includes rosemary being bought from a national producer, whereas extraction of the active principle, production, and packaging is done at the production facilities. Lastly, an economic analysis has shown that this project requires an investment of 7 M€. The product would be sold at pharmacies at a retail price of 11.99 €. This analysis has shown that HaliTeddies may be considered to be a profitable and viable business.","PeriodicalId":36339,"journal":{"name":"U.Porto Journal of Engineering","volume":"12 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2022-09-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"75010493","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}
引用次数: 0
Xylitol 木糖醇
U.Porto Journal of Engineering Pub Date : 2022-09-27 DOI: 10.1108/eb059460
Filipa Carvalho, Francisca Duarte, Laura Pedreiras, Vanessa Posada, Margarida Brito
{"title":"Xylitol","authors":"Filipa Carvalho, Francisca Duarte, Laura Pedreiras, Vanessa Posada, Margarida Brito","doi":"10.1108/eb059460","DOIUrl":"https://doi.org/10.1108/eb059460","url":null,"abstract":"The main purpose of this project was the eco-valorisation of the tomato plant residues. The chemical product design method was used to select the best idea based on 4 steps: needs, ideas, selection, and manufacturing.Liquid xylitol is here proposed for the valorisation of tomato plant residues, which is an alternative sweetener with a lower glycemic index that can be produced from the hemicellulose found in leaves and stems. Its production would require an alkaline extraction with sodium hydroxide, enzymatic hydrolyses using endo-1,4-β-xylanase, and yeast fermentation with Candida tropicalis.Liquid sweetener with 72% xylitol and other components (D-glucose, D-mannose, D-galactose, L-arabinose, and lignin), commercialised as NITS - Natural Incredible Tomato Sweetener, could be sold for 2.25 €·L-1 for companies and the same price per bottle of 500 mL for individual consumption.","PeriodicalId":36339,"journal":{"name":"U.Porto Journal of Engineering","volume":"16 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2022-09-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"82714351","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}
引用次数: 1
EcoSmile EcoSmile
U.Porto Journal of Engineering Pub Date : 2022-09-27 DOI: 10.24840/2183-6493_008.005_0009
Ana Ferreira, Daniela Oliveira, L. Barroca, Margarida Peixoto, I. Martins
{"title":"EcoSmile","authors":"Ana Ferreira, Daniela Oliveira, L. Barroca, Margarida Peixoto, I. Martins","doi":"10.24840/2183-6493_008.005_0009","DOIUrl":"https://doi.org/10.24840/2183-6493_008.005_0009","url":null,"abstract":"EcoSmile is an innovative Portuguese product of quercitrin, an antioxidant extracted from kiwi branches residues with the objective of promoting circular economy. Since periodontal disease currently affects 20 to 50% of the world's population, there is a need for an efficient product to treat this condition. This antioxidant can be used as an active ingredient of this mouthwash as it has anti-inflammatory characteristics and repairs gingival tissues.The extraction and manufacturing processes were studied and scaled to an industrial level. The plant would be installed in Felgueiras, and a team of 14 workers was considered. An economic assessment was made, finding that an investment of €2,550,000 would be necessary. The project is economically viable and capable of generating a financial surplus.","PeriodicalId":36339,"journal":{"name":"U.Porto Journal of Engineering","volume":"2 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2022-09-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"88939183","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}
引用次数: 0
Anti-photoaging Cream using a Quercus Suber Extract 使用栎树提取物的抗光老化霜
U.Porto Journal of Engineering Pub Date : 2022-09-27 DOI: 10.24840/2183-6493_008.005_0004
Adriana Oliveira, A. Silva, Catarina Neves, Francisca Leal, I. Pinho, Maria Ana Silva, Y. Manrique
{"title":"Anti-photoaging Cream using a Quercus Suber Extract","authors":"Adriana Oliveira, A. Silva, Catarina Neves, Francisca Leal, I. Pinho, Maria Ana Silva, Y. Manrique","doi":"10.24840/2183-6493_008.005_0004","DOIUrl":"https://doi.org/10.24840/2183-6493_008.005_0004","url":null,"abstract":"This work aims at developing a new chemical product, which involves all the product design stages, starting from the evaluation of market needs, generation of ideas, selection of the selected idea and finally, the decision of the manufacturing process.During this analysis, it was decided to use the ellagic acid extracted from cork powder, a cork industry waste, to create our final product: an anti-photoaging cream free of parabens and fragrances. This decision results from the protective role of ellagic acid against UV-B-induced oxidative stress, reducing wrinkles and sun inflammation consequences. A rough economic feasibility analysis was carried out based on an industrial showcase, in which it was calculated the Net Present Value of 1.6 M€, so the project was considered viable. It was also determined the Internal Return Rate - value of 85 %, and the Payback Time was set at 3.3 years.","PeriodicalId":36339,"journal":{"name":"U.Porto Journal of Engineering","volume":"1 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2022-09-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"80777392","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}
引用次数: 0
Valorization of Ellagic Acid from Chestnut Shell as a Natural Anti-anxiety Food Supplement 栗壳鞣花酸作为天然抗焦虑食品补充剂的价值评价
U.Porto Journal of Engineering Pub Date : 2022-09-27 DOI: 10.24840/2183-6493_008.005_0002
Joana Vasconcelos Neto, Carla Batista, Beatriz Moreira Franco, Susana Dinis, Joana Teixeira, Y. Manrique
{"title":"Valorization of Ellagic Acid from Chestnut Shell as a Natural Anti-anxiety Food Supplement","authors":"Joana Vasconcelos Neto, Carla Batista, Beatriz Moreira Franco, Susana Dinis, Joana Teixeira, Y. Manrique","doi":"10.24840/2183-6493_008.005_0002","DOIUrl":"https://doi.org/10.24840/2183-6493_008.005_0002","url":null,"abstract":"Mental health is on the agenda, especially in times of pandemic due to the COVID-19 virus. Nowadays, psychological problems, such as anxiety and depression, have been more discussed and have become even more critical during confinement. This paper proposes the development process of an innovative product whose active ingredient - ellagic acid, extracted from the chestnut shell - has anxiolytic properties and can be potentially used in consumers' daily lives, preventing this type of illness. The product presented, Do Nut Stress – Acid ellagic enriched pancakes for anxiety control, consists of a pancake powder, considered a healthy and nutritious meal.","PeriodicalId":36339,"journal":{"name":"U.Porto Journal of Engineering","volume":"6 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2022-09-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"85621635","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}
引用次数: 1
Antibacterial Finishing of Cotton Bed Sheets using Olive Leaves Extract 橄榄叶提取物对棉质床单的抗菌整理
U.Porto Journal of Engineering Pub Date : 2022-09-27 DOI: 10.24840/2183-6493_008.005_0005
A. Baptista, Beata Shymon, Beatriz Silva, C. Lopes, Marta Pereira, Sofia Brandão, Y. Manrique
{"title":"Antibacterial Finishing of Cotton Bed Sheets using Olive Leaves Extract","authors":"A. Baptista, Beata Shymon, Beatriz Silva, C. Lopes, Marta Pereira, Sofia Brandão, Y. Manrique","doi":"10.24840/2183-6493_008.005_0005","DOIUrl":"https://doi.org/10.24840/2183-6493_008.005_0005","url":null,"abstract":"The main goal of this project consisted of the conceptualization and development of a product related to the olive tree chemical features to monetize the wastes of the olive fruit exploitation. The most abundant by-product of the olive fruit harvest is the olive leaves, used as the raw material in this project. By following the steps of Chemical Product Design, it was decided to pursue the idea of creating antibacterial cotton bed sheets impregnated with olive leaves extract, mainly composed of oleuropein. The production process includes a pre-treatment of the olive leaves, oleuropein extraction, and supercritical impregnation. The estimated amount of leaves required is 39 g/m2 of cotton, considering a cotton fabric with 115 GSM.","PeriodicalId":36339,"journal":{"name":"U.Porto Journal of Engineering","volume":"2012 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2022-09-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"86396787","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}
引用次数: 0
Jellyapic
U.Porto Journal of Engineering Pub Date : 2022-09-27 DOI: 10.24840/2183-6493_008.005_0013
David Aguillar, Juliana Magalhães, Marta Sousa, Marta Rêgo, Vasco Ribeiro, A. F. Freitas
{"title":"Jellyapic","authors":"David Aguillar, Juliana Magalhães, Marta Sousa, Marta Rêgo, Vasco Ribeiro, A. F. Freitas","doi":"10.24840/2183-6493_008.005_0013","DOIUrl":"https://doi.org/10.24840/2183-6493_008.005_0013","url":null,"abstract":"This work consists of developing a strawberry plant-based product, an anti-glycemic gelatin. The selected product is a vegan origin gelatin containing sinapic acid, extracted from the strawberry leaves. A Chemical Product Design (CPD) approach was used to satisfy the customers' needs with a new product. The main purpose of this gelatin is to value the strawberry leaves' wide variety of health properties, mainly its anti-glycemic property. After the definition of the production process, it was concluded that using the total amount of about 133 tons of dry strawberry leaves available per year in Portugal, it was possible to produce up to 26 million gelatin packets yearly. Finally, an economic analysis was performed to evaluate the product viability, resulting in profits from product sales from the third year forward. The net present value (NPV) and the internal rate of return (IRR) were also calculated, resulting in about 15 million euros and 30 %, respectively.","PeriodicalId":36339,"journal":{"name":"U.Porto Journal of Engineering","volume":"27 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2022-09-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"72830190","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}
引用次数: 0
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