Advances in Science and Technology Research Journal最新文献

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Investigation of Cutting Tool Wear in the Milling Process of the Inconel 718 Alloy 铬镍铁合金 718 铣削过程中的切削刀具磨损研究
Advances in Science and Technology Research Journal Pub Date : 2024-04-01 DOI: 10.12913/22998624/182944
Paweł Piórkowski, Wojciech Borkowski, M. Bartoszuk, E. Miko
{"title":"Investigation of Cutting Tool Wear in the Milling Process of the Inconel 718 Alloy","authors":"Paweł Piórkowski, Wojciech Borkowski, M. Bartoszuk, E. Miko","doi":"10.12913/22998624/182944","DOIUrl":"https://doi.org/10.12913/22998624/182944","url":null,"abstract":"The article presents the results of research on the wear of the cutting tool in the process of high feed milling and plunge milling of the Inconel 718 alloy. A specially designed milling head was used in the study, allowing both of the previously mentioned milling methods to be implemented with a single tool. Ceramic inserts CNGN120712 in versions CS300 and CW100 were used for the research. During the experiment, the values of cutting depth a p [mm], cutting width a e [mm] and feed per edge f z [mm/edge] were changed. The study was conducted under the conditions of accelerated wear. The results show the tool life in individual tests using the parameter of the material volume predicted to be removed in the tool life cycle G max [cm 3 ], obtained by third degree polynomial approximation. For milling with high feeds, the volume of material expected to be removed over the tool life cycle G max ranged from 54 to 106 cm 3 , whereas for plunge milling it ranged from 33 to 73 cm 3 .","PeriodicalId":517116,"journal":{"name":"Advances in Science and Technology Research Journal","volume":"57 2","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140357219","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
Damages of the Section Insulator Guide Caused by Electric Arc 电弧对分段绝缘子导轨造成的损坏
Advances in Science and Technology Research Journal Pub Date : 2024-04-01 DOI: 10.12913/22998624/184091
Jarosław Konieczny, Krzysztof Labisz
{"title":"Damages of the Section Insulator Guide Caused by Electric Arc","authors":"Jarosław Konieczny, Krzysztof Labisz","doi":"10.12913/22998624/184091","DOIUrl":"https://doi.org/10.12913/22998624/184091","url":null,"abstract":"This article presents research on the influence of an electric arc on the properties and structure of a traction section guide made of ETP (electrolytic tough pitch) copper in a segment insulator of a railway section. An electrical discharge occurring during use, which may accompany the passage of the pantograph current collector between adjacent guides, may cause many physical phenomena. In addition to existing guide wear mechanisms, such as friction, corrosion, and/or oxidation, the action of an electric arc also has a devastating effect on the guide in use, causing its complete destruction in extreme cases. The aim of the investigation was to determine what type of damage to the sectional guide in real operation conditions was caused by the impact of an electric arc that is induced when the pantograph passes from one guide to the adjacent one. The paper presents the results of tests on an operational guide made of hard electrolytic copper Cu-ETP, in particular the results of microscopic observations, the results of microscopic tests obtained using the ZEISS SUPRA 25 scanning electron microscope, as well as the analysis of the chemical composition in micro-areas (EDS - Energy-dispersive X-ray spectroscopy). On the basis of the tests carried out, it was found that the dominant destructive mechanism of the guide is the electric arc, the presence of elements from the external environment was also determined, and the degree of damage was analysed depending on the conditions and operating times.","PeriodicalId":517116,"journal":{"name":"Advances in Science and Technology Research Journal","volume":"49 16","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140357348","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
The Effect of HVOF Spray Distance on Solid Particle Erosion Resistance of WC-based Cermets Bonded by Co, Co-Cr and Ni Deposited on Mg-alloy Substrate HVOF 喷射距离对镁合金基底上沉积的钴、钴铬和镍结合的 WC 基金属陶瓷的固体颗粒抗侵蚀性的影响
Advances in Science and Technology Research Journal Pub Date : 2024-04-01 DOI: 10.12913/22998624/184025
Ewa Jonda, L. Łatka, Aleksandra Lont, K. Gołombek, M. Szala
{"title":"The Effect of HVOF Spray Distance on Solid Particle Erosion Resistance of WC-based Cermets Bonded by Co, Co-Cr and Ni Deposited on Mg-alloy Substrate","authors":"Ewa Jonda, L. Łatka, Aleksandra Lont, K. Gołombek, M. Szala","doi":"10.12913/22998624/184025","DOIUrl":"https://doi.org/10.12913/22998624/184025","url":null,"abstract":"Magnesium alloys are very interesting engineering materials because of their high strength-to-density ratio. On the other hand, they are characterized by low hardness as well as low erosion resistance. Because of these reasons, their applications in the industry are very limited. The article presents the results of the high velocity oxy-fuel (HVOF) spraying of the hard cermet coatings onto AZ31 magnesium alloy substrate. Three feedstock powders were used in the process with composition (wt.%): WC-12Co, WC-10Co-4Cr and WC-20Cr 3 C 2 Ni. The spray distance (SD) was selected as a variable parameter with values equal to 320 and 400 mm. Observations carried out under a scanning electron microscope (SEM) revealed a typical HVOF-sprayed microstructure with a compact structure and low po - rosity (below 3 vol.%). The hardness of the manufactured coatings, ranging from 912 HV0.2 to 1328 HV0.2, what was significantly higher than the substrate. The solid particle erosion tests were carried out according to the ASTM G76-04 standard. Erosive experiments were done for 30°, 60° and 90° inclination angles of the nozzle using Al 2 O 3 abrasive. Erosion tests confirm that cermets exhibit substantial erosion resistance better than the substrate. The highest erosion resistance was noted for WC-10Co-4Cr coatings. The erosion rate for cermet coatings was mostly below 0.9 mg/min, whereas for the AZ31 it was more than 1.5 mg/min. In the case of the average erosion value, it was between 12 and 22 times lower than for the substrate. Results analysis reveal that shorter spray distance decreases porosity, increases hardness, and finally supports erosion resistance of the cermets.","PeriodicalId":517116,"journal":{"name":"Advances in Science and Technology Research Journal","volume":"3 3","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140353337","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
Strength Analysis Aspects of Psyllium/Thermoplastic Starch Films under Impact Loading Conditions 冲击载荷条件下车前子/热塑性淀粉薄膜的强度分析问题
Advances in Science and Technology Research Journal Pub Date : 2024-04-01 DOI: 10.12913/22998624/185393
K. Beer-Lech, Paweł Kołodziej, A. Skic, Ricardo Branco
{"title":"Strength Analysis Aspects of Psyllium/Thermoplastic Starch Films under Impact Loading Conditions","authors":"K. Beer-Lech, Paweł Kołodziej, A. Skic, Ricardo Branco","doi":"10.12913/22998624/185393","DOIUrl":"https://doi.org/10.12913/22998624/185393","url":null,"abstract":"Tensile test under quasi-static loads conditions is usually used to determine the mechanical strength of thermo-plastic starch films. This kind of test does not fully illustrate the load conditions for packaging films, which, under the conditions of use, are succumb to dynamic loads. Thus, the aim of the study was to present the possibilities of using a patented soft tissues measurement testing station to analyze the mechanical strength of thermoplastic starch (TPS) films under impact loading conditions. Two groups of film specimens containing the addition of psyllium husks (TPS/PH) and psyllium flour (TPS/PF) were used for the measurements. The casting method was applied, and glycerol was used as a plasticizer. Microstructure of the specimen surface was analyzed by stereoscopic microscopy. Specimens with the addition of psyllium flour had a more uniform microstructure. The maximum break - ing forces obtained during impact tests for these films were 5 times higher than specimens containing psyllium seed husk. The same behaviour was found with respect to stresses with average values of 48.6 MPa for TPS/PF and 20.2 MPa for TPS/PH. Moreover, research confirms usefulness of patented soft tissues measurement testing station to analyse the mechanical strength of thermoplastic starch films.","PeriodicalId":517116,"journal":{"name":"Advances in Science and Technology Research Journal","volume":"2 7","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140353372","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
Computational Fluid Dynamics Studies of a Vertical Axis Wind Turbine with a Variable Swept Area 具有可变扫掠面积的垂直轴风力涡轮机的计算流体动力学研究
Advances in Science and Technology Research Journal Pub Date : 2024-04-01 DOI: 10.12913/22998624/185255
Idzi Pędzisz, P. Magryta, K. Pietrykowski
{"title":"Computational Fluid Dynamics Studies of a Vertical Axis Wind Turbine with a Variable Swept Area","authors":"Idzi Pędzisz, P. Magryta, K. Pietrykowski","doi":"10.12913/22998624/185255","DOIUrl":"https://doi.org/10.12913/22998624/185255","url":null,"abstract":"The article presents the results of the Computational Fluid Dynamics (CFD) research on a vertical axis wind turbine with a variable swept area. The tested turbine has four sets of blades, each of which consists of two moving parts. By changing the angle between these parts, it is possible to change the swept area of the turbine wheel to adjust the characteristics of the turbine to the current wind speed. In the case of strong wind, it is possible to fold blades to protect the rotor against damage. The 3D-CFD model was tested using the ANSYS Fluent software. The four rotors differing in the blade angle were analyzed. The tests were carried out for different wind speeds. The results are presented as pressure and velocity distributions as well as streamlines around the rotor. In addition, the waveforms of the torque acting on a single blade and on the entire rotor are shown. The average rotor torque was also calculated. These findings enabled us to create the characteristics of the power factor for different rotational speeds of the rotor. The results show that the adjustment of the swept area makes the z-turbine have a flexible operating range.","PeriodicalId":517116,"journal":{"name":"Advances in Science and Technology Research Journal","volume":"2 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140354082","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
Numerical Simulation of Erosion on Aluminium Plate with a Cylindrical Hole 带圆柱孔的铝板上的侵蚀数值模拟
Advances in Science and Technology Research Journal Pub Date : 2024-04-01 DOI: 10.12913/22998624/183623
Halima Hadžiahmetović, E. Džaferović, Sanda Midžić Kurtagić, Rejhana Blažević
{"title":"Numerical Simulation of Erosion on Aluminium Plate with a Cylindrical Hole","authors":"Halima Hadžiahmetović, E. Džaferović, Sanda Midžić Kurtagić, Rejhana Blažević","doi":"10.12913/22998624/183623","DOIUrl":"https://doi.org/10.12913/22998624/183623","url":null,"abstract":"The purpose of the present study is to simulate erosion on the aluminium plate with a cylindrical hole caused by solid particles after passing through 90° elbow, using the Computational Fluid Dynamics (CFD), the Discrete Phase Model (DPM), and erosion equations. Discrete trajectories of solid particles are calculated using the Lagrangian approach, while the simulation of the fluid was obtained by solving the fluid motion equation using the Eulerian approach. Supplementary sub-models are incorporated into the software to enhance the accuracy of particle trajectory calculations within the simulated geometry. These sub-models include collisions of solid particles with walls (stochastic model) and erosion model. The numerical simulation results obtained in this paper were compared with the existing experimental results from the group of authors, demonstrating a good match. The paper provides the main characteristics of the mathematical model, along with the interpretation of results and a discussion, with the key findings highlighted in the conclusion. The findings indicate that erosion process is significantly influenced by both the particle impact velocity and impact angle, which are key parameters in many erosion equa - tions. Furthermore, it is observed that the velocity of the particles is consistently lower than the mean velocity of the air. Additionally, the angle at which the particles impact the aluminium plate is not always exactly 90° due to multiple collisions with the wall, signifying that the particles do not move exclusively vertically.","PeriodicalId":517116,"journal":{"name":"Advances in Science and Technology Research Journal","volume":"5 11","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140354625","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
A Study on the Channel and Gap Flow Simulation For Electrical Discharge Micro-Drilling of Inconel 718 Superalloy Inconel 718 超耐热合金放电微钻孔的通道和间隙流动模拟研究
Advances in Science and Technology Research Journal Pub Date : 2024-04-01 DOI: 10.12913/22998624/183998
M. Machno, M. Trajer, Adrian Czeszkiewicz, Paulina Żurawka
{"title":"A Study on the Channel and Gap Flow Simulation For Electrical Discharge Micro-Drilling of Inconel 718 Superalloy","authors":"M. Machno, M. Trajer, Adrian Czeszkiewicz, Paulina Żurawka","doi":"10.12913/22998624/183998","DOIUrl":"https://doi.org/10.12913/22998624/183998","url":null,"abstract":"The process of electrical discharge micro-drilling (micro-EDD) of micro holes is used in the aviation, automotive and biomedical industries. In this process, an important issue affecting the stability and efficiency of the process is the flow of the working fluid through the tool electrode channel and the front and side gap areas. Because tool electrodes have diameters below 1 mm. Many factors present in the EDM-drillig process occurring on a micro scale mean that a full explanation of the phenomena affecting the process is limited. The solution is to analyze the phenomena in the process based on the results of numerical simulations, which are based on real measurements. The aim of this work is to analyze the flow of de-ionized water through a brass single-channel electrode with a channel diameter of 0.11 mm and a front and side gap. The liquid flow was analyzed for various variants (with and without cavitation, with added rotation of the tool electrode, with and without surface roughness with material particles). In simulation, it is impor - tant to gradually increase the complexity of the model, starting with the simplest model and gradually adding further phenomena. Analysis of the simulation results showed a significant impact on the liquid flow of cavitation, as well as the presence of vortex gaps in some areas, which have a significant impact on the process of drilling micro holes.","PeriodicalId":517116,"journal":{"name":"Advances in Science and Technology Research Journal","volume":"3 7","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140354521","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
Screw Extrusion as a Scalable Technology for Manufacturing Polylactide Composite with Graphene Filler 螺杆挤压是制造含石墨烯填料的聚乳酸复合材料的可扩展技术
Advances in Science and Technology Research Journal Pub Date : 2024-04-01 DOI: 10.12913/22998624/184152
D. Kaczor, Krzysztof Bajer, A. Raszkowska-Kaczor, Oksana Krasinska, Grzegorz Domek, P. Szroeder
{"title":"Screw Extrusion as a Scalable Technology for Manufacturing Polylactide Composite with Graphene Filler","authors":"D. Kaczor, Krzysztof Bajer, A. Raszkowska-Kaczor, Oksana Krasinska, Grzegorz Domek, P. Szroeder","doi":"10.12913/22998624/184152","DOIUrl":"https://doi.org/10.12913/22998624/184152","url":null,"abstract":"The use of carbon nanomaterials as fillers in the process of obtaining polymer composites by extrusion poses many problems. The high agglomeration ability and low bulk density of carbon nanomaterials do not allow to easy production of composites characterized by very good dispersion of the filler in the polymer matrix, which is required to obtain a high-quality product. The advantage of this type of fillers is that the improvement of the composite properties can be achieved even at a low degree of filling. In this article, we describe a method for obtaining poly - lactide composites with a nanofiller in the form of graphene nanoplatelets. To overcome the difficulties associated with the use of graphene, we divided the process of obtaining composites into two stages. In the first stage, we made a masterbatch containing 25 wt.% graphene, from which, in the second stage, we obtained target composites containing from 0.1 to 2 wt.% graphene. A twin-screw extruder was used in both stages. The tested filling levels had no significant impact on the recorded processing parameters. The composites obtained by the described meth - od are characterized by good dispersion of graphene. However the graphene agglomerates can be observed in the polymer matrix. Composites were tested by SEM, FTIR, DSC and MFR methods. Mechanical tests such as static tension, three-point bending, impact strength showed that the addition of 0.5 wt.% of graphene improves tensile strength by 10%, Young’s modulus by 19% and both flexural strength and flexural modulus by 15%. The carbon filler has an impact on crystallization process of the polymer matrix by acting as a nucleating agent.","PeriodicalId":517116,"journal":{"name":"Advances in Science and Technology Research Journal","volume":"54 32","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140357286","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
Modifications of the Formal Risk Analysis and Assessment for the Information System Security 对信息系统安全正式风险分析和评估的修改
Advances in Science and Technology Research Journal Pub Date : 2024-04-01 DOI: 10.12913/22998624/185162
Imed El Fray, Artur Wiliński
{"title":"Modifications of the Formal Risk Analysis and Assessment for the Information System Security","authors":"Imed El Fray, Artur Wiliński","doi":"10.12913/22998624/185162","DOIUrl":"https://doi.org/10.12913/22998624/185162","url":null,"abstract":"In the article, a modification of formal model of risk analysis (FoMRA) was proposed. The modified FoMRA1 method takes into account the guidelines of ISO/IEC 27001 and ISO/IEC 27005 standards. The applied modifica - tion and abstraction by resources and security controls (also called countermeasures) significantly shortened the time of risk weight calculation in comparison with the MEHARI method. An attempt was also made to further reduce the time of risk analysis using agents collecting information and data from various network nodes, from operating systems and devices, and additional agents containing information on reports on security procedures, security services, security management and organizational activities related to the information systems (mainte - nance, insurance, outsourcing contracts, etc.) and transfer it to the local FoMRA1 database. The obtained results indicate that the proposed method together with agents installed in various nodes enable a quick reaction to the system threats and prevention of their impacts (quasi-real-time security monitoring system).","PeriodicalId":517116,"journal":{"name":"Advances in Science and Technology Research Journal","volume":"2 3","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140353349","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
Influence of Selected Weather Conditions on the Photovoltaic System Efficiency in Central Poland – Case Study 波兰中部特定天气条件对光伏系统效率的影响 - 案例研究
Advances in Science and Technology Research Journal Pub Date : 2024-04-01 DOI: 10.12913/22998624/184104
M. Sarniak
{"title":"Influence of Selected Weather Conditions on the Photovoltaic System Efficiency in Central Poland – Case Study","authors":"M. Sarniak","doi":"10.12913/22998624/184104","DOIUrl":"https://doi.org/10.12913/22998624/184104","url":null,"abstract":"The article details the data obtained from monitoring the photovoltaic (PV) system in 2021–2023, equipped with a module for measuring basic weather parameters. The PV system under consideration, with a peak output of 3.2 kW p , is connected to the electricity grid and is mounted on the flat roof of the building. The annual relative yields of the generated energy were about 10% less than estimated, and their monthly distributions were asymmetric. In the “sum - mer” months (i.e., from April to September), the PV system generated, on average, about 75% of the whole year’s energy. The histograms of the PV system’s active power output showed that, on average, about 40% of the time, the PV inverter operated in underloaded mode. For selected weather conditions measured on site, a regression analysis was conducted with the active output power of the PV system. The main objective of the work was to develop a com - prehensive method for analysing PV plant monitoring data and the impact of weather conditions on its performance. The proposed method was realized as a case study for central Poland but can be implemented anywhere.","PeriodicalId":517116,"journal":{"name":"Advances in Science and Technology Research Journal","volume":"69 16","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140355886","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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