Sustainable Technology eJournal最新文献_第2页

Development of Technologies for Hot Pressing of Rods Made From 7075 Aluminum Alloy on a Radialshear Mill of a New Design – Numerical Modeling 7075铝合金棒材在新型径向剪切轧机上热压工艺的发展——数值模拟

Sustainable Technology eJournal Pub Date : 2020-10-30 DOI: 10.15587/1729-4061.2020.214919

S. Mashekov, Yerik Nugman, A. Mashekova, Aimangul Sekerbek, N. Sembayev, S. Akparova

{"title":"Development of Technologies for Hot Pressing of Rods Made From 7075 Aluminum Alloy on a Radialshear Mill of a New Design – Numerical Modeling","authors":"S. Mashekov, Yerik Nugman, A. Mashekova, Aimangul Sekerbek, N. Sembayev, S. Akparova","doi":"10.15587/1729-4061.2020.214919","DOIUrl":"https://doi.org/10.15587/1729-4061.2020.214919","url":null,"abstract":"The paper proposes a radial shear mill (RSM) of a new design, which allows manufacturing metal rods of small diameters or wires with a fine-grained structure. The paper presents the results of modeling the evolution of the structure during hot rolling-pressing of aluminum alloy 7075 on the RSM. Mathematical modeling of the technological process was carried out using the MSC. SuperForge, and the empirical Johnson-Mehl-Avrami-Kolmogorov equation was used to predict the passage of softening processes. Due to the absence of the coefficients of the Avrami equation, a series of experiments on physical modeling of the rolling-pressing technological process were conducted on an STD 812 torsion rheometer. The experiments were conducted at the temperature range of 250–450 ℃ and a strain rate of 1.0–20 s-1. By using physical modeling, it was proved that during processing on the RSM, it is necessary to develop a torsional deformation over the entire section of the workpiece, which leads to effective refinement of the structure. The derived formulas and simulation modeling of the obtained values of the stress-strain state (SSS) were used to simulate the technology of the combined process. Moreover, rational temperature-rate conditions were determined to deform the workpiece on the RSM. It was proved by mathematical modeling that shear deformations develop along the entire section of the workpiece during processing on the RSM, which leads to effective refinement of the structure and the formation of a fine-grained structure in the rods, i. e. products of the required quality are manufactured.","PeriodicalId":136014,"journal":{"name":"Sustainable Technology eJournal","volume":"14 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2020-10-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126847757","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

Cryogenically Applied Support and Damping Structures for Chatter Suppression in the Machining of Thin-Walled Components 薄壁零件加工中低温支撑和阻尼结构的颤振抑制

Sustainable Technology eJournal Pub Date : 2020-10-30 DOI: 10.2139/ssrn.3722034

Eva Jaeger, J. Baumann, D. Biermann

{"title":"Cryogenically Applied Support and Damping Structures for Chatter Suppression in the Machining of Thin-Walled Components","authors":"Eva Jaeger, J. Baumann, D. Biermann","doi":"10.2139/ssrn.3722034","DOIUrl":"https://doi.org/10.2139/ssrn.3722034","url":null,"abstract":"Lightweight components with low wall thickness continue to gain technological and economic importance in aerospace and other industries. Thereby, the low wall thickness and thus high compliance of such workpieces may cause the occurrence of undesired vibrations under the characteristic load of machining operations. The suppression of dynamic effects such as regenerative chatter represents a central requirement for milling operations with regard to the achievable component qualities and process efficiency. Certain approaches base on the application of support structures or damping elements, which are attached to the workpiece. After processing the thin-walled components, however, the added structures have to be removed in elaborate processes. In this paper, a new approach is presented which is focusing on an optimised process stabilisation method using cryogenic solidified coolant. By injecting coolant emulsion into the CO2 snow jet and applying it specifically to thin-walled workpieces, stiffening support structures were generated and damping elements attached. The ice layer melts off after machining and returns into the lubricant circuit with no need for conditioning or additional filtering. Modal tests and machining experiments demonstrated the applicability of the presented approach and a significant decrease of the dynamic compliance and deflection of the workpiece during milling operations.","PeriodicalId":136014,"journal":{"name":"Sustainable Technology eJournal","volume":"32 2 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2020-10-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131881509","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

Emerging Technologies in Biodiversity Governance: Gaps and Opportunities for Action 生物多样性治理中的新兴技术:差距和行动机会

Sustainable Technology eJournal Pub Date : 2020-07-16 DOI: 10.2139/ssrn.3653021

F. Rabitz, Jesse L. Reynolds, E. Tsioumani

引用次数: 2

Development of a Powerful Low-voltage DC Converter for Systems of Electric Power Accumulation 大功率低压直流蓄能变换器的研制

Sustainable Technology eJournal Pub Date : 2020-04-30 DOI: 10.15587/1729-4061.2020.198950

A. Panchenko, D. Karlov, Yuriy Kusakin, Maksim Kuravskiy, O. Drol

{"title":"Development of a Powerful Low-voltage DC Converter for Systems of Electric Power Accumulation","authors":"A. Panchenko, D. Karlov, Yuriy Kusakin, Maksim Kuravskiy, O. Drol","doi":"10.15587/1729-4061.2020.198950","DOIUrl":"https://doi.org/10.15587/1729-4061.2020.198950","url":null,"abstract":"The study offers a solution to the problem associated with the use of batteries in autonomous solar and wind power plants, power installations, and electric vehicles. It is known that one battery element can produce 1.2–4 V, which is not enough for subsequent transformations. There is a need to complete the battery, in series-parallel connection, with several elements to several thousand elements. During its operation, slight deviations of the voltage of the elements occur, which subsequently accumulate and lead to the battery failure. To prevent such phenomena, diagnostics with an accuracy of 0.1–0.001 V per element is necessary. This complicates the control system and forces the entire battery to be rejected in case of failure of a certain number of elements. The load on the surrounding space for the disposal of lead, lithium, and cadmium is increasing. It has been established that effective converters of direct current to direct current at the indicated voltages and capacities do not exist. Voltage converters from level 3 use an intermediate link to convert the magnetic field. This type of low voltage converter is used only at low power. It was proved that a significant number of battery elements connected in a series in parallel can be replaced with one equivalent in energy. The conducted tests have established that it is advisable to produce a subsequent increase in voltage with ionistors by charging them in parallel followed by a discharge in the series. A mathematical description of the operation of the converter was developed, starting from the moment of switching on and reaching the steady state with subsequent response to a change in the load. Since the operation of the converter involves significant currents, the components of the internal resistances of all elements are taken into account. This approach helps study possible technical implementations, identify patterns when varying its parameters, and optimize conditions, depending on the type of chemical elements and consumer power","PeriodicalId":136014,"journal":{"name":"Sustainable Technology eJournal","volume":"14 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2020-04-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125260263","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

Development of a High Sensitive Inductive Movement Sensor 高灵敏度感应式运动传感器的研制

Sustainable Technology eJournal Pub Date : 2020-04-30 DOI: 10.15587/1729-4061.2020.201859

A. Perederko

{"title":"Development of a High Sensitive Inductive Movement Sensor","authors":"A. Perederko","doi":"10.15587/1729-4061.2020.201859","DOIUrl":"https://doi.org/10.15587/1729-4061.2020.201859","url":null,"abstract":"Research on a contact induction displacement sensor over short distances is presented. A ferrite core with a winding and a movable armature is used as a sensor. There is an air gap between the core and the armature. To solve the problem of improving the accuracy of measurement, the sensor is included in the bridge measuring circuit, which is powered by high-frequency alternating current. To increase the sensitivity of the indicated sensor to movement, a differential circuit for its inclusion is proposed. Also, in order to increase sensitivity, the resonant mode of operation of the bridge measurement circuit is used. To maintain a constant voltage of the power generator, a phase-locked loop is used. As a result of the study of the induction displacement sensor, practical results were obtained with a maximum displacement of ±0.6 mm. The sensor has not been studied for large displacements, since with an increase in the indicated displacement, the nonlinearity of the displacement-current transformation appears. The maximum sensitivity of the differential sensor in the indicated range of movement 2.44 μA/μm is obtained without the use of a phase-locked loop. The use of a phase-locked-loop frequency adjustment system increased the sensitivity to 3.48 μA/μm. During the study, the dependence of the sensitivity of the sensor on the frequency of the power generator was determined, which allows to determine the optimal power frequency of the measuring bridge circuit. Studies have shown that the use of contact inductive meters have the prospect of application and reserves for improvement. And the use of differential inclusion of the sensor and the resonant mode of operation gives a significant increase in the sensitivity of the primary transducer at small displacements. An inexpensive sensor has been developed that will be useful for many applications where it is necessary to measure displacements and linear dimensions by contact methods","PeriodicalId":136014,"journal":{"name":"Sustainable Technology eJournal","volume":"8 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2020-04-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121008317","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: 2

Semiconducting Single Wall Carbon Nanotubes as Artificial Pili for Enhanced CO 2 Clostridium ljungdahlii Biofilms 半导体单壁碳纳米管作为增强型永格氏梭菌生物膜的人工菌毛

Sustainable Technology eJournal Pub Date : 2020-04-22 DOI: 10.2139/ssrn.3575133

Zhaodong Li, Wei Xiong, Bertrand J. Tremolet de Villers, Chao Wu, Bennett Addison, D. Svedružić, J. Blackburn

{"title":"Semiconducting Single Wall Carbon Nanotubes as Artificial Pili for Enhanced CO 2 Clostridium ljungdahlii Biofilms","authors":"Zhaodong Li, Wei Xiong, Bertrand J. Tremolet de Villers, Chao Wu, Bennett Addison, D. Svedružić, J. Blackburn","doi":"10.2139/ssrn.3575133","DOIUrl":"https://doi.org/10.2139/ssrn.3575133","url":null,"abstract":"Bio-electrochemical systems have been applied successfully for electroreduction of waste carbon dioxide to chemicals. Despite the recent advances in biocathode design and performance, a fundamental understanding of how support electrode materials affect growth, organization and electroactivity of biofilms, and electron transfer across the electrode/bacterium interface is still lacking. Our study demonstrates that surface nanostructuring with semiconducting single-walled carbon nanotubes (SWCNTs) is beneficial for interfacial charge transfer and CO2 reducing activities of Clostridium ljungdahlii biofilms by mimicking the biological functions of conductive bio-wires, not by the commonly suggested mechanism of simply increasing biofilm coverage. We also show that applying a negative potential during biofilm growth is essential for production of electroactive biofilms. 13C isotope labeling experiments conclusively demonstrate that biocathodes can simultaneously utilize ethanol while reducing CO2. Deuterium isotope labeling experiments confirmed that the availability of electrochemically produced H2 as a redox mediator does not limit the efficiency of extracellular electron transfer (EET) and CO2 electro-reduction. These results provide important mechanistic information about EET across the bacterium/material interface in a model biohybrid system.","PeriodicalId":136014,"journal":{"name":"Sustainable Technology eJournal","volume":"189 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2020-04-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121287929","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

Does Geography Matter? A Study of Technological Learning and Innovation in the Solar Photovoltaic Balance-of-Systems Industry 地理因素重要吗?太阳能光伏平衡系统产业的技术学习与创新研究

Sustainable Technology eJournal Pub Date : 2020-04-21 DOI: 10.2139/ssrn.3581755

Xue Gao, V. Rai

{"title":"Does Geography Matter? A Study of Technological Learning and Innovation in the Solar Photovoltaic Balance-of-Systems Industry","authors":"Xue Gao, V. Rai","doi":"10.2139/ssrn.3581755","DOIUrl":"https://doi.org/10.2139/ssrn.3581755","url":null,"abstract":"Technologies whose future development trajectory depends significantly on local factors (e.g., administrative codes, user preferences, etc.) exhibit interactive feedback between geographical factors and technological learning. However, in such a context it is unclear which factors influence the degree of localized learning and the extent to which and at which geographic level localized learning is important for innovation. To empirically investigate firms’ learning and innovation processes in relation to geography, in this paper we use patent citation analysis on a unique database of PV balance-of-system (BOS) patents in the U.S. issued between 2000 to 2014. The PV BOS industry offers an excellent empirical opportunity to examine the linkages between geography and learning in the context of technologies in the deployment process, wherein features of such technologies are associated with the locations in which they are applied and deployed. We find that localized learning is more important for technologies that are more associated with the local context. We also find that extra-local knowledge significantly contributes to the quality of patents. Overall, our findings suggest that for technological learning and innovation in PV BOS technologies, neither local learning nor extra-local learning is uniformly superior in its importance. Thus policies to support deployment technologies should pay explicit attention to the local vs. extra-local knowledge needs of local firms. For example, local demand-pull policies may be more helpful in earlier phases of market development, while helping firms build bridges to extra-local knowledge networks may be more helpful later on.","PeriodicalId":136014,"journal":{"name":"Sustainable Technology eJournal","volume":"6 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2020-04-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129486882","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

Automated Irrigation and Crop Prediction 自动化灌溉和作物预测

Sustainable Technology eJournal Pub Date : 2020-04-08 DOI: 10.2139/ssrn.3564633

Komal Menger, Sowmya Iyer, Srushti Jamsandekar, Rohit Barve

引用次数: 1

Detection of Micro-Cracks in Electroluminescence Images of Photovoltaic Modules 光伏组件电致发光图像中微裂纹的检测

Sustainable Technology eJournal Pub Date : 2020-04-08 DOI: 10.2139/ssrn.3563821

Natasha Mathias, F. Shaikh, Chirayu Thakur, Sweekrithi Shetty, Pratibha R. Dumane, Dr. Satishkumar Chavan

引用次数: 10

Exploring Urban High-Tech Landscapes to Overcome Standard Industrial Classification: A Cross-Industry Network Analysis in Paris and Toronto 探索城市高科技景观以克服标准产业分类:巴黎和多伦多的跨行业网络分析

Sustainable Technology eJournal Pub Date : 2020-03-25 DOI: 10.2139/ssrn.3560763

Paola Antonelli, M. Cucculelli

{"title":"Exploring Urban High-Tech Landscapes to Overcome Standard Industrial Classification: A Cross-Industry Network Analysis in Paris and Toronto","authors":"Paola Antonelli, M. Cucculelli","doi":"10.2139/ssrn.3560763","DOIUrl":"https://doi.org/10.2139/ssrn.3560763","url":null,"abstract":"Despite periodic updating, conventional administrative datasets and industry codes often fail to provide classifications for services and the emerging industries of the twenty-first century. For researchers, these data challenges present particular barriers to understanding the nature of business activities. For policymakers, these information gaps feed through into policy gaps, which can limit the ability to design effective interventions to encourage local entrepreneurship and innovation in high-technology sectors. The present paper worked with non-traditional data sources to avoid current classification systems. Using metadata about high-tech firms from CrunchBase, this paper studied the structure of cross-industry landscape, individual network characteristics, and major technological complementarities of high-tech industry networks. We investigate two of the most promising high-tech hubs, Paris and Toronto, to explore the potential of such approach. Results shed light on the complex networks of cross-sectoral horizontal and vertical linkages that characterize the two hubs and help policy makers and venture capitalists to deeply understand the business landscape of high-tech local companies.","PeriodicalId":136014,"journal":{"name":"Sustainable Technology eJournal","volume":"50 4 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2020-03-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127171328","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