Pub Date : 2024-07-01DOI: 10.1088/1361-6552/ad589c
Jorge Pinochet
This year marks half a century since Stephen Hawking made his greatest scientific discovery by theoretically proving that 'black holes ain't so black', as they behave like hot bodies with an absolute temperature that depends inversely on their mass. This discovery is expressed by a simple and elegant equation known as the Hawking temperature. The best way to commemorate this great scientific event is by bringing it to a wide audience. The simplest and most transparent and intuitive tool to achieve this goal is dimensional analysis. The objective of this work is to use this tool to derive the Hawking equation, reveal its meaning, and explore its main physical consequences.
{"title":"Hawking for everyone: commemorating half a century of an unfinished scientific revolution","authors":"Jorge Pinochet","doi":"10.1088/1361-6552/ad589c","DOIUrl":"https://doi.org/10.1088/1361-6552/ad589c","url":null,"abstract":"This year marks half a century since Stephen Hawking made his greatest scientific discovery by theoretically proving that 'black holes ain't so black', as they behave like hot bodies with an absolute temperature that depends inversely on their mass. This discovery is expressed by a simple and elegant equation known as the Hawking temperature. The best way to commemorate this great scientific event is by bringing it to a wide audience. The simplest and most transparent and intuitive tool to achieve this goal is dimensional analysis. The objective of this work is to use this tool to derive the Hawking equation, reveal its meaning, and explore its main physical consequences.","PeriodicalId":39773,"journal":{"name":"Physics Education","volume":"13 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141519214","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}
Pub Date : 2024-07-01DOI: 10.1088/1361-6552/ad5780
Edy Wibowo, Naily Ulya, Putut Marwoto, Suwandi and Suproyogi
Lato Lato is a toy that consists of two identical solid balls that are secured together with a rope and can be used as a learning tool in physics. In this study, we examined why the Lato Lato toy uses two balls with the same mass rather than balls with different masses. The collision of the two Lato Lato balls can be considered an elastic collision. The two balls move symmetrically at the same velocity and form a semi-circular route with opposing motion directions when we use Lato Lato with the same ball mass ( ). The angular momentum of the two balls is also the same but in opposite directions, so they cancel each other out. Hence, the two balls travel steadily when Lato Lato is performed. This condition leads to a balanced movement of the Lato Lato system and prevents it from collapsing. On the other hand, because of their disparate masses ( ), the two balls of Lato Lato move in an imbalanced manner. A lighter ball travels farther because it moves more quickly than a heavier ball. The angular momentum of the two balls is in opposite directions but not of the same magnitude, so they do not cancel each other out. This results in unstable movement of the two balls when Lato Lato is played. Therefore, the two balls no longer collide centrally, like in Lato Lato, with the same mass, but the collision is glancing. Then, the motion of the two balls facilitates collapse easily. This work can enrich students' understanding of collisions beyond the collisions of two objects commonly discussed in textbooks.
{"title":"The dynamics of Lato Lato ball collisions","authors":"Edy Wibowo, Naily Ulya, Putut Marwoto, Suwandi and Suproyogi","doi":"10.1088/1361-6552/ad5780","DOIUrl":"https://doi.org/10.1088/1361-6552/ad5780","url":null,"abstract":"Lato Lato is a toy that consists of two identical solid balls that are secured together with a rope and can be used as a learning tool in physics. In this study, we examined why the Lato Lato toy uses two balls with the same mass rather than balls with different masses. The collision of the two Lato Lato balls can be considered an elastic collision. The two balls move symmetrically at the same velocity and form a semi-circular route with opposing motion directions when we use Lato Lato with the same ball mass ( ). The angular momentum of the two balls is also the same but in opposite directions, so they cancel each other out. Hence, the two balls travel steadily when Lato Lato is performed. This condition leads to a balanced movement of the Lato Lato system and prevents it from collapsing. On the other hand, because of their disparate masses ( ), the two balls of Lato Lato move in an imbalanced manner. A lighter ball travels farther because it moves more quickly than a heavier ball. The angular momentum of the two balls is in opposite directions but not of the same magnitude, so they do not cancel each other out. This results in unstable movement of the two balls when Lato Lato is played. Therefore, the two balls no longer collide centrally, like in Lato Lato, with the same mass, but the collision is glancing. Then, the motion of the two balls facilitates collapse easily. This work can enrich students' understanding of collisions beyond the collisions of two objects commonly discussed in textbooks.","PeriodicalId":39773,"journal":{"name":"Physics Education","volume":"38 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141503015","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}
Pub Date : 2024-06-23DOI: 10.1088/1361-6552/ad559e
Hollis Williams
There exist many magnetic levitation toys, most of which use spin-stabilised levitation. A more recent demonstration features a levitating lightbulb which is made to float in the air and light up by magnetic forces. We study the workings of the lightbulb and explain how it operates via a different type of levitation known as electrodynamic suspension. We also examine the stability of the device, showing that levitation can be maintained even if the bulb is prevented from rotating.
{"title":"How to levitate a lightbulb","authors":"Hollis Williams","doi":"10.1088/1361-6552/ad559e","DOIUrl":"https://doi.org/10.1088/1361-6552/ad559e","url":null,"abstract":"There exist many magnetic levitation toys, most of which use spin-stabilised levitation. A more recent demonstration features a levitating lightbulb which is made to float in the air and light up by magnetic forces. We study the workings of the lightbulb and explain how it operates via a different type of levitation known as electrodynamic suspension. We also examine the stability of the device, showing that levitation can be maintained even if the bulb is prevented from rotating.","PeriodicalId":39773,"journal":{"name":"Physics Education","volume":"46 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-06-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141503016","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}
Pub Date : 2024-06-23DOI: 10.1088/1361-6552/ad4f3e
Juan Sabí‘n
Abstract thinking and scientific argumentation are two of the more important high-order cognitive skills that students at secondary level need to develop in the learning of physics. In this paper a new methodology based on constructivism’s view of education is presented by using counterintuitive experiments under a POE strategy (Predict, Explain, Observe). The experiments consist in a race of two soda can, one of them previously shaken, over an inclined plane; and the movement of a double cone object, built by two joined funnels, over two convergent inclined rails. The unexpected outcome of both experiments challenges the prior ideas of the students and provokes a higher engagement in their learning process. The results of a pilot experience applying this methodology suggest that using counterintuitive experiments under PEO strategy is an effective methodology to introduce the teaching of abstract concepts as moment of inertia and centre of mass. It also helps identifying students’ prior knowledge, promoting the use of scientific reasoning, and training students in the activation of their abstraction skills.
{"title":"Promoting abstract thinking and scientific argumentation in the teaching of physics","authors":"Juan Sabí‘n","doi":"10.1088/1361-6552/ad4f3e","DOIUrl":"https://doi.org/10.1088/1361-6552/ad4f3e","url":null,"abstract":"Abstract thinking and scientific argumentation are two of the more important high-order cognitive skills that students at secondary level need to develop in the learning of physics. In this paper a new methodology based on constructivism’s view of education is presented by using counterintuitive experiments under a POE strategy (Predict, Explain, Observe). The experiments consist in a race of two soda can, one of them previously shaken, over an inclined plane; and the movement of a double cone object, built by two joined funnels, over two convergent inclined rails. The unexpected outcome of both experiments challenges the prior ideas of the students and provokes a higher engagement in their learning process. The results of a pilot experience applying this methodology suggest that using counterintuitive experiments under PEO strategy is an effective methodology to introduce the teaching of abstract concepts as moment of inertia and centre of mass. It also helps identifying students’ prior knowledge, promoting the use of scientific reasoning, and training students in the activation of their abstraction skills.","PeriodicalId":39773,"journal":{"name":"Physics Education","volume":"8 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-06-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141503023","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}
Pub Date : 2024-06-23DOI: 10.1088/1361-6552/ad559f
Weisong Yi and Haiyou Deng
Using smartphones to explore the physical laws of musical instruments is not only scientifically intriguing but also practically feasible. Here an experimental scheme based on a smartphone and mobile application (Phyphox) is devised to investigate the vibration law of guitar strings. By quantitatively measuring the length, diameter and vibration frequency of guitar strings, the experimental results convincingly demonstrate the validity of the vibration law of guitar strings. The research embodies the concept of ‘from life to physics, from physics to society’, and is beneficial for students to comprehend the physical laws of guitar string vibration as well as the principle behind guitar sounds. The smartphone-based physics experiments can be performed outside the classic physics laboratory, which expands the methods and space of teaching physics experiments, and relates reality to physics laws.
{"title":"Smartphone-based experiments exploring the physical laws of guitar string vibrations","authors":"Weisong Yi and Haiyou Deng","doi":"10.1088/1361-6552/ad559f","DOIUrl":"https://doi.org/10.1088/1361-6552/ad559f","url":null,"abstract":"Using smartphones to explore the physical laws of musical instruments is not only scientifically intriguing but also practically feasible. Here an experimental scheme based on a smartphone and mobile application (Phyphox) is devised to investigate the vibration law of guitar strings. By quantitatively measuring the length, diameter and vibration frequency of guitar strings, the experimental results convincingly demonstrate the validity of the vibration law of guitar strings. The research embodies the concept of ‘from life to physics, from physics to society’, and is beneficial for students to comprehend the physical laws of guitar string vibration as well as the principle behind guitar sounds. The smartphone-based physics experiments can be performed outside the classic physics laboratory, which expands the methods and space of teaching physics experiments, and relates reality to physics laws.","PeriodicalId":39773,"journal":{"name":"Physics Education","volume":"21 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-06-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141503017","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}
Pub Date : 2024-06-14DOI: 10.1088/1361-6552/ad4f40
Sherwin J Marte, M. A. A. C. Bug-os, U. Pili
Classroom experiments using modern experimental tools like smartphones are in growing popularity. Hence, this study conducted a comparative experiment to determine the acceleration values due to gravitational force in free fall and projectile motions using simple materials and the sound sensor. In this experiment, the relationship between the height and the time squared of the fall in both free fall and projectile motions is represented in regression model. Notably, experimental values for g for free fall and projectile motions are close to the accepted acceleration value due to gravitational force.
使用智能手机等现代实验工具进行课堂实验越来越受欢迎。因此，本研究进行了一项对比实验，利用简单的材料和声音传感器来确定自由落体和抛射体运动中重力引起的加速度值。在该实验中，自由落体和抛射体运动的高度与下落时间平方之间的关系用回归模型来表示。值得注意的是，自由落体和抛射体运动中 g 的实验值接近公认的重力加速度值。
{"title":"Comparative experiment using free fall and projectile motions in determining the acceleration due to gravitational force","authors":"Sherwin J Marte, M. A. A. C. Bug-os, U. Pili","doi":"10.1088/1361-6552/ad4f40","DOIUrl":"https://doi.org/10.1088/1361-6552/ad4f40","url":null,"abstract":"Classroom experiments using modern experimental tools like smartphones are in growing popularity. Hence, this study conducted a comparative experiment to determine the acceleration values due to gravitational force in free fall and projectile motions using simple materials and the sound sensor. In this experiment, the relationship between the height and the time squared of the fall in both free fall and projectile motions is represented in regression model. Notably, experimental values for g for free fall and projectile motions are close to the accepted acceleration value due to gravitational force.","PeriodicalId":39773,"journal":{"name":"Physics Education","volume":"47 48","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-06-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141339492","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}
Pub Date : 2024-06-14DOI: 10.1088/1361-6552/ad4fd6
Alessandro Salmoiraghi, L. Gratton, M. Di Mauro, P. Onorato
We present a quantitative optical low-cost experiment aimed at introducing students to wave-particle duality from a phenomenological point of view. The experiment, focused on light diffraction, clearly shows the intermediate crossover regime which characterize the transition from geometric optics (in which light behaves like a stream of particles) to the Fraunhofer diffraction regime (where the wave aspects are most evident). It can also be considered for introducing students to the uncertainty relations through diffraction of light waves. The experiments do not require expensive materials or specific laboratory instruments and employ the sensors and camera of common mobile devices. The experiments were tested with master students in mathematics and physics, who aim at becoming high school teachers.
{"title":"Introducing wave-particle duality with low-cost quantitative experiments on light diffraction","authors":"Alessandro Salmoiraghi, L. Gratton, M. Di Mauro, P. Onorato","doi":"10.1088/1361-6552/ad4fd6","DOIUrl":"https://doi.org/10.1088/1361-6552/ad4fd6","url":null,"abstract":"We present a quantitative optical low-cost experiment aimed at introducing students to wave-particle duality from a phenomenological point of view. The experiment, focused on light diffraction, clearly shows the intermediate crossover regime which characterize the transition from geometric optics (in which light behaves like a stream of particles) to the Fraunhofer diffraction regime (where the wave aspects are most evident). It can also be considered for introducing students to the uncertainty relations through diffraction of light waves. The experiments do not require expensive materials or specific laboratory instruments and employ the sensors and camera of common mobile devices. The experiments were tested with master students in mathematics and physics, who aim at becoming high school teachers.","PeriodicalId":39773,"journal":{"name":"Physics Education","volume":"48 32","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-06-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141339353","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}
Pub Date : 2024-06-14DOI: 10.1088/1361-6552/ad4f3f
N. A. Machado, M. Hahn, F. Cruz, P. S. Carvalho
This study addresses the challenges faced by students with colour blindness during the exploration of light spectra, emphasizing the crucial adaptation of educational materials for effective learning. The proposed solution, characterized by its low-cost and straightforward implementation, involves the use of smartphone apps, notably the ‘ColorADD,’ to assist students who cannot perceive colours in understanding spectral phenomena. This topic is integrated into the curricula of both high school and undergraduate physics courses in Portugal and Brazil. This approach represents a tangible opportunity to promote inclusive scientific education, fostering active participation and ensuring equal opportunities for colour-blind students without compromising their overall visual perception.
{"title":"Identifying colours in the absorption spectrum with an app","authors":"N. A. Machado, M. Hahn, F. Cruz, P. S. Carvalho","doi":"10.1088/1361-6552/ad4f3f","DOIUrl":"https://doi.org/10.1088/1361-6552/ad4f3f","url":null,"abstract":"This study addresses the challenges faced by students with colour blindness during the exploration of light spectra, emphasizing the crucial adaptation of educational materials for effective learning. The proposed solution, characterized by its low-cost and straightforward implementation, involves the use of smartphone apps, notably the ‘ColorADD,’ to assist students who cannot perceive colours in understanding spectral phenomena. This topic is integrated into the curricula of both high school and undergraduate physics courses in Portugal and Brazil. This approach represents a tangible opportunity to promote inclusive scientific education, fostering active participation and ensuring equal opportunities for colour-blind students without compromising their overall visual perception.","PeriodicalId":39773,"journal":{"name":"Physics Education","volume":"67 5","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-06-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141342430","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}
Pub Date : 2024-06-14DOI: 10.1088/1361-6552/ad5130
Vítor Oliveira, Gustavo Brazil, Paulo Rodrigues, Pedro L. Almeida
We present a low-cost experimental apparatus designed for studying the rotational dynamics of a meter stick. This apparatus uses everyday laboratory supplies, 3D printed parts, and an Arduino board for data acquisition. It consists of a common bearing fixed to a vertical axle, connected to the meter stick through a 3D printed spindle adapter. A thread attached to a hanging weight and winded around the spindle applies a constant external torque to the stick. The moment of inertia of the apparatus may be changed by incorporating weights into the apparatus through 3D printed adapters. An Arduino board records the time interval between consecutive half turns of the stick, allowing the calculation of the angular displacement over time. The data collected from experiments is compared with theoretical models. Among others, the effect of the applied torque, air resistance and moment of inertia of the stick is studied. This experimental apparatus is particularly suitable for undergraduate students enrolled in a classical mechanics course, offering them a practical, hand-on experience while remaining cost-effective.
我们介绍一种低成本的实验装置，用于研究米杆的旋转动力学。该装置使用日常实验室用品、3D 打印部件和 Arduino 板进行数据采集。它由一个固定在垂直轴上的普通轴承组成，通过一个 3D 打印的主轴适配器与米杆相连。一根连接到悬挂砝码上的线缠绕在主轴上，对测量杆施加恒定的外部扭矩。通过 3D 打印适配器将砝码放入仪器中，可改变仪器的惯性矩。Arduino 电路板可记录棍子连续转半圈之间的时间间隔，从而计算出随时间变化的角位移。实验收集的数据与理论模型进行了比较。其中，研究了施加扭矩、空气阻力和棍子惯性矩的影响。该实验装置特别适合修读经典力学课程的本科生，既能为他们提供实际操作经验，又能保证成本效益。
{"title":"Studying the rotational dynamics of a meter stick using the Arduino board and 3D printed parts","authors":"Vítor Oliveira, Gustavo Brazil, Paulo Rodrigues, Pedro L. Almeida","doi":"10.1088/1361-6552/ad5130","DOIUrl":"https://doi.org/10.1088/1361-6552/ad5130","url":null,"abstract":"We present a low-cost experimental apparatus designed for studying the rotational dynamics of a meter stick. This apparatus uses everyday laboratory supplies, 3D printed parts, and an Arduino board for data acquisition. It consists of a common bearing fixed to a vertical axle, connected to the meter stick through a 3D printed spindle adapter. A thread attached to a hanging weight and winded around the spindle applies a constant external torque to the stick. The moment of inertia of the apparatus may be changed by incorporating weights into the apparatus through 3D printed adapters. An Arduino board records the time interval between consecutive half turns of the stick, allowing the calculation of the angular displacement over time. The data collected from experiments is compared with theoretical models. Among others, the effect of the applied torque, air resistance and moment of inertia of the stick is studied. This experimental apparatus is particularly suitable for undergraduate students enrolled in a classical mechanics course, offering them a practical, hand-on experience while remaining cost-effective.","PeriodicalId":39773,"journal":{"name":"Physics Education","volume":"30 50","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-06-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141340407","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}
Pub Date : 2024-06-14DOI: 10.1088/1361-6552/ad52e1
M. Ziese
Discharging a capacitor is a standard experiment in physics education. Here it is described in a form that challenges students’ preconceptions, since the voltage across the capacitor is observed to oscillate after switching off the power supply. The aim is to demonstrate the importance and relevance of experiments and measurements, even if these are in contradiction with expectations and textbooks. Students have the opportunity to develop a quantitative model for the observations and explore the transition from oscillatory to overdamped behaviour—with the latter being the standard in textbook presentations—in further measurements. The experiment can also be used in schools, since the concept of tuning the damping by resistance variation is rather intuitive and insightful even without a formal mathematical background.
{"title":"Discharging a capacitor","authors":"M. Ziese","doi":"10.1088/1361-6552/ad52e1","DOIUrl":"https://doi.org/10.1088/1361-6552/ad52e1","url":null,"abstract":"Discharging a capacitor is a standard experiment in physics education. Here it is described in a form that challenges students’ preconceptions, since the voltage across the capacitor is observed to oscillate after switching off the power supply. The aim is to demonstrate the importance and relevance of experiments and measurements, even if these are in contradiction with expectations and textbooks. Students have the opportunity to develop a quantitative model for the observations and explore the transition from oscillatory to overdamped behaviour—with the latter being the standard in textbook presentations—in further measurements. The experiment can also be used in schools, since the concept of tuning the damping by resistance variation is rather intuitive and insightful even without a formal mathematical background.","PeriodicalId":39773,"journal":{"name":"Physics Education","volume":"53 29","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-06-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141345313","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}
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