Global Challenges最新文献_第10页

Sustainable Production Insight Through LCA and LCC Analysis of Injection Overmolded Structural Electronics Manufactured through Roll-to-Roll Processes 通过LCA和LCC分析通过卷对卷工艺制造的注塑覆模结构电子产品的可持续生产洞察

IF 4.9 4区综合性期刊

Global Challenges Pub Date : 2023-10-25 DOI: 10.1002/gch2.202300015

Minna Räikkönen, Laura Sokka, Lotta Hepo-oja, Sirpa Nordman, Thomas M. Kraft

{"title":"Sustainable Production Insight Through LCA and LCC Analysis of Injection Overmolded Structural Electronics Manufactured through Roll-to-Roll Processes","authors":"Minna Räikkönen, Laura Sokka, Lotta Hepo-oja, Sirpa Nordman, Thomas M. Kraft","doi":"10.1002/gch2.202300015","DOIUrl":"10.1002/gch2.202300015","url":null,"abstract":"Printed electronics (PE) have provided new material and application opportunities for devices and systems as well as new manufacturing routes that all need to be considered for commercialization. This paper introduces a case study with universally relevant manufacturing processes and applications in the PE area, focusing on the Life Cycle Assessment (LCA) and Life Cycle Costing (LCC) of the Personal Activity Monitor (PAM) device. In the study, the PAM device's most important costs and environmental impacts during the prototype pilot production and device use phases are identified and assessed. Additionally, the potential environmental impacts of post-consumption scenarios are considered. The LCA results indicate that the roll-to-roll (R2R) assembly of electronics and the R2R injection over-molding are generally the most prominent production process steps affecting the results. From the LCC perspective, the capitial expenditure (CAPEX) contributor is the R2R assembly pilot line, due to its high investment cost and long operating time compare to other production assets. The traditional electronic components are the major operating expenditures (OPEX), especially the microcontroller units (MCUs) and accelerometers, in contrast to the low impact from the printed electronics. There are several advantages to applying LCA and LCC since they provide explanations of the relationships between cost, environmental, design, and manufacturing characteristics.","PeriodicalId":12646,"journal":{"name":"Global Challenges","volume":"7 11","pages":""},"PeriodicalIF":4.9,"publicationDate":"2023-10-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC10632665/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"134648835","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"综合性期刊","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Neo-Antigen-Reactive T Cells Immunotherapy for Colorectal Cancer: A More Personalized Cancer Therapy Approach 结直肠癌的新抗原反应性T细胞免疫治疗:一种更加个性化的癌症治疗方法

IF 4.9 4区综合性期刊

Global Challenges Pub Date : 2023-10-17 DOI: 10.1002/gch2.202200186

Guan-Liang Chen, De-Xia Kong, Yan Lin

引用次数: 0

Maisotsenko Cycle for Heat Recovery in Gas Turbines: A Fundamental Thermodynamic Assessment 燃气轮机热回收的Maisotsenko循环:基本热力学评估

IF 4.9 4区综合性期刊

Global Challenges Pub Date : 2023-10-15 DOI: 10.1002/gch2.202300178

Rasikh Tariq, Hakan Caliskan, Nadeem Ahmed Sheikh

{"title":"Maisotsenko Cycle for Heat Recovery in Gas Turbines: A Fundamental Thermodynamic Assessment","authors":"Rasikh Tariq, Hakan Caliskan, Nadeem Ahmed Sheikh","doi":"10.1002/gch2.202300178","DOIUrl":"10.1002/gch2.202300178","url":null,"abstract":"This paper reports the Maisotsenko's cycle-based waste heat recovery system with enhanced humidification to exploit the maximum waste heat recovery potential of the gas turbine. This research uses an integrated methodology coupling thermodynamic balances with heat transfer model of air saturator. The performance of the system is deduced which are assisted with sensitivity analysis indicating the optimal mass flow rate ratio (0.7–0.8) and pressure ratio (4.5–5.0) between the topping and bottoming cycles, and the air saturator split (extraction) ratio (0.5). The net-work output, energy, and exergy efficiencies of the system are found to be ≈58.39 MW, ≈55.85%, and ≈52.79%, respectively. The maximum exergy destruction ratios are found as 68.2% for the combustion chamber, 16.0% for the topping turbine, 5.7% for topping compressor, 4.9% air saturator. The integration of Maisotsenko's cycle-based waste heat recovery system with a comprehensive thermodynamic model, as demonstrated in this research, offers valuable insights into enhancing the efficiency, cost-effectiveness, and environmental impact of gas turbines. By presenting fundamental equations related to thermodynamic balances, this work serves as an invaluable educational resource, equipping future researchers and students with the knowledge and skills needed to advance the study of thermodynamics and sustainable energy solutions.","PeriodicalId":12646,"journal":{"name":"Global Challenges","volume":"7 11","pages":""},"PeriodicalIF":4.9,"publicationDate":"2023-10-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC10632667/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"134648833","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"综合性期刊","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Masthead: (Global Challenges 10/2023) 刊头：（2023年10月全球挑战）

IF 4.9 4区综合性期刊

Global Challenges Pub Date : 2023-10-11 DOI: 10.1002/gch2.202370070

引用次数: 0

(Global Challenges 10/2023) （2023年10月全球挑战）

IF 4.9 4区综合性期刊

Global Challenges Pub Date : 2023-10-11 DOI: 10.1002/gch2.202370069

引用次数: 0

The Effects of Bromine Additives on the Recyclability of Injection Molded Electronic Waste Polymers 溴添加剂对注塑电子废聚合物可回收性的影响

IF 4.9 4区综合性期刊

Global Challenges Pub Date : 2023-10-10 DOI: 10.1002/gch2.202300157

Ville Lahtela, Katriina Mielonen, Prashant Parkar, Timo Kärki

{"title":"The Effects of Bromine Additives on the Recyclability of Injection Molded Electronic Waste Polymers","authors":"Ville Lahtela, Katriina Mielonen, Prashant Parkar, Timo Kärki","doi":"10.1002/gch2.202300157","DOIUrl":"10.1002/gch2.202300157","url":null,"abstract":"Excessive waste amounts, such as waste electrical and electronic equipment (WEEE) and plastic waste, have increased simultaneously with the development of society. Despite the increased material amounts, the recycling rates are too low and those have a great potential to contribute actions toward a circular economy. A certain restricted factor for recycling is the heterogenous nature of materials, such as WEEE-included additives. This study investigates the effects of a WEEE polymer including bromine on recycling ability, analyzing its physical and mechanical features. The study demonstrates that polymer sorting is profitable for WEEE polymers from the material qualitative perspective, because various processability and material features are achieved in the study between material categories, and especially unidentified polymers have the weakest features in the studied tests. The separation of bromine concentration is also recommended because bromine-free materials have more advanced features that can be confirmed by statistical analyses. The achieved results support the idea that novel circular economy actions have the potential for effective, efficient WEEE polymer recycling processes with technological innovations, especially when all variables (e.g., recycling cycles and process parameters) are observed and it enables an option to reduce the need for virgin plastic.","PeriodicalId":12646,"journal":{"name":"Global Challenges","volume":"7 11","pages":""},"PeriodicalIF":4.9,"publicationDate":"2023-10-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC10632664/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"134648836","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"综合性期刊","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Influence of Coal Gangue Powder on the Macroscopic Mechanical Properties and Microstructure of Recycled Aggregate Concrete 煤矸石粉对再生骨料混凝土宏观力学性能和微观结构的影响。

IF 4.9 4区综合性期刊

Global Challenges Pub Date : 2023-10-03 DOI: 10.1002/gch2.202300189

Zhi Zhenli, Zhile Shu, Qihong Wu, Jiaxin Li, Haikuang Wu, Wenlong Chen, Xinhang Zeng

{"title":"Influence of Coal Gangue Powder on the Macroscopic Mechanical Properties and Microstructure of Recycled Aggregate Concrete","authors":"Zhi Zhenli, Zhile Shu, Qihong Wu, Jiaxin Li, Haikuang Wu, Wenlong Chen, Xinhang Zeng","doi":"10.1002/gch2.202300189","DOIUrl":"10.1002/gch2.202300189","url":null,"abstract":"The construction and coal industries generate substantial industrial waste, including coal gangue and construction and demolition (C&D) waste, leading to environmental pollution and high disposal costs. Integrating recycled aggregates (RAs) and coal gangue powder (CGP) into concrete is an effective approach for waste management. However, CGP can affect the performance of traditional recycled concrete. This study primarily aims to optimize the utilization of RAs and CGP while maintaining concrete performance. They utilized orthogonal experimental designs and microscopic characterization techniques, including scanning electron microscopy (SEM), energy-dispersive X-ray spectroscopy (EDS), and X-ray diffraction (XRD). Orthogonal experimental analysis indicated that with a water-cement ratio (WCR) of 0.5 and replacement rates of 10% for CGP and 60% for RA, compressive and splitting tensile strengths reached 73.6% and 77.4% of ordinary C30 concrete, respectively. This mix proportion minimizes strength decline in coal gangue powder-recycled aggregate concrete (CGP-RAC) while maximizing recycled material replacement. Microscopic analysis revealed that CGP increased the Ca/Si ratio in cement paste, impeding hydration reactions, resulting in a looser internal structure and reduced concrete strength. These findings are anticipated to provide fresh theoretical insights for solid waste recycling and utilization.","PeriodicalId":12646,"journal":{"name":"Global Challenges","volume":"7 10","pages":""},"PeriodicalIF":4.9,"publicationDate":"2023-10-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1002/gch2.202300189","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"41198779","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"综合性期刊","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Sustainable Engineering Design in Education: A Pilot Study of Teaching Right-to-Repair Principles through Project-Based Learning 教育中的可持续工程设计：通过项目学习教学修复权原则的试点研究。

IF 4.9 4区综合性期刊

Global Challenges Pub Date : 2023-10-03 DOI: 10.1002/gch2.202300158

Sam Fishlock, Matthew Thompson, Anoop Grewal

{"title":"Sustainable Engineering Design in Education: A Pilot Study of Teaching Right-to-Repair Principles through Project-Based Learning","authors":"Sam Fishlock, Matthew Thompson, Anoop Grewal","doi":"10.1002/gch2.202300158","DOIUrl":"10.1002/gch2.202300158","url":null,"abstract":"Over 60 million tons of E‐waste is expected to be generated in 2023, with associated significant impacts on health and the environment. To reduce the number of products sent to landfills, “Right to Repair” (RtR) movements are gaining momentum in many countries, including the UK, USA, and EU member states. While Universities are seen as important stakeholders to drive forward sustainable design practices, there is currently little work looking at training undergraduate design engineers in the principles of designing household products in support of RtR. In particular, the project‐based learning (PBL) pedagogy shows promise in engaging and training students with the skills and knowledge required to successfully design products for RtR. In this paper, a pilot‐study of teaching engineers is presented to design products compatible with RtR principles, alongside many technical skills, in a first‐year PBL course. The key outputs of this paper are the design of the module, which can be used to help inform first‐year engineering education, the high engagement of students, with 100% of respondents agreeing that they intend to try to implement sustainable design practices in future, and some of the innovative features that students implement in their projects.","PeriodicalId":12646,"journal":{"name":"Global Challenges","volume":"7 10","pages":""},"PeriodicalIF":4.9,"publicationDate":"2023-10-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1002/gch2.202300158","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"41198783","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"综合性期刊","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

(Global Challenges 9/2023) （全球挑战9/2023）

IF 4.9 4区综合性期刊

Global Challenges Pub Date : 2023-09-23 DOI: 10.1002/gch2.202370067

引用次数: 0

Masthead: (Global Challenges 9/2023) 刊头：（全球挑战9/2023）

IF 4.9 4区综合性期刊

Global Challenges Pub Date : 2023-09-23 DOI: 10.1002/gch2.202370068

引用次数: 0