In order to break through the limitation of traditional experiment teaching,virtual reality technology method was integrated into the physical experiment teaching,and a virtual simulation operation platform of“Preparation of Liquid Crystal Cell and Measurement of Electro-Optic Effect”was constructed.The operation steps and methods of virtual experiment were introduced.At the same time,the experimental principle was analyzed and explained by the numerical simulation method,and the experimental contents were expanded and designed.The teaching practices showed that the experimental design was helpful to improve students’practical operation skills and stimulate their interest in learning and innovative thinking.

Helmholtz Coils are widely used in scientific research and industrial fields,and studying its magnetic field distribution is an important part of university physics experiments.The article uses the smartphone’s built- in magnetometer and physics experiment application (phyphox)to quantitatively measure the current-carrying Helmholtz coils’central axiscentral radial and three-dimensional magnetic field distribution.Comparison of experimental measurement results with theoretical calculations, which is consistent and the measurement accuracy is within the acceptable range,which confirms the feasibility of the method.The introduction of smar phones as sensors in traditional university physics experiments can not only reduce the cost of experiments,but also stimulate interest in learning and enhance students’desire to explore.

Newton’s law of cooling has some limitations.The applicability of Newton cooling law at different temperatures is discussed.The results show that the applicability of Newton’s cooling law decreases with the increase of temperature difference,and the relative error is calculated.The Newton’s cooling law is modified under different temperature differences,and the application range of Newton’s cooling law is given.

It studies magnetie induction intensity distribution characteristics on the central axis of the magneticrod . When different numbers of steel balls ( non-magnetic ) are arranged on the axis and the steel balls armagnetized , it studies the corresponding magnetie induction intensity distribution characteristies , laws of changeand fitting formulas on thean deepen people ' s in-depth understanding of the distribution of magnetic.

Different from the traditional confirmatory physics experiment, it introduces a DIY wireless power transmission via coupled magnetic resonance experiment that can fully exercise students hands-on ability, deeply enhance students "participation and experience in the course. It specifically introduces the experimental methods for studying the two major factors that affeet the effect of wireless power transmission, and how to arrange the experimental content of the self-made simple wireless power transmission system led by students, then gives suggestions for assessment and class time allocation

Optical encryption technology is the focus of information optics course to expand the application of theoretical knowledge , but the traditional teaching way is given priority to with the mathematical model of this technology on more , lack of experimental apparatus of visual presentation , students are the process and application of optical encryption effect . Therefore , it designs a set of hybrid optical transform information encryption experimental platform , the platform using the simulation software of independent writing.The realization of image encryption and decryption simulation and key role exploration ; Use of scaffolding to decrypt optical path devices simulation realization of optical path . The service of information optics teaching platform , high degree of visualization interactive easy to operate , will instantiate the theory model , and combined with the simulation and the optical path , helps the student to the optical encryption technology systematic comprehensive understanding , improve the students ' innovation ability and information technology application

The formation mechanism of HCS was studied at 6-311+G(d,p) base level by density functional B3LYP method,and a reasonable ice phase synthesis reaction channel was obtained.The obtained information is helpful to further study the formation of molecules containing sulfur atoms in the interstellar medium.

According to the characteristies of electric field distribution between conductors of infinitely long hyperbolic cylinder.The distribution function of electric potential and electric field intensity between conductors of infinitely long hyperbolic cylinder is derived by using the properties of analytic function, and the equation of equipotential line and electric field line is obtained.Using mathematical software Matlab drawing equipotentia line and electric transmission line.

AlCl molecules play an important role in the fields of astrophysics,chemistry and laser cooling.It uses the high-precision multi-reference configuration interaction method (MRCI+Q)to study the low-lying excited states of AlCl molecules.Based on the obtained potential energy curves(PECs), the spectroscopic constants of the fitted electronic states are in good agreement with the experimental values.The dipole moments (DMs) of electronic states and the curves of spin-orbit (SO) matrix elements varying with the internuclear distance are calculated.At the same time,the transition properties of AlCl molecules were calculated ,including transition dipole moments(TDMs)Franck-Condon factors(FCFs)and radiation lifetime.The FCFs of the AlCl molecule 1'II-1'∑*are highly diagonal and have the potential to be used as a laser cooling light evele The calculated results have certain reference value for the subsequent experimental research on the electronic structure properties of AlCl molecules.

The dynamic viscosity of fluid is an important parameter to describe the viscosity movement of fluid There are many methods to measure the fluid dynamic viscosity in experiment, such as rotating cylinder method,falling ball method,capillary method and so on.In this paper,based on the simple pendulum movement of a common magnetic ball,using the Hall element measuring magnetic field in different time, and the location of the different time is obtained by analysis of variation of the magnetic field,the location of the magnetic ball is obtained by fitting oscillation amplitude over time,finally the value of the dynamic viscosity of air will be obtained through data analysis.

In order to solve the problem that traditional microscopy systems cannot achieve high-resolution and large-field imaging at the same time due to the fixed resolution-field product, lensless imaging technology emerged at the historic moment.However,the existing lensless imaging devices are low in automation and intelligence,and unable to achieve adaptive imaging.In response to the above problems,a lensless intelligent microscopie imaging device was designed,which includes a lensless imaging module,an adaptive displacement stage and a computer-side host computer.lt can not only achieve higher resolution imaging under a large field of view,but also can achieve adaptive adjustment of the imaging field of view with an adaptive stage.lt has a simple structure. no aberration interference, and high degree of automation, which can meet the needs of teaching demonstrations and demonstration experiments.

The tensile method is generally used to measure the young’s modulus of metal wire in college physics experiment courses,but the function of the experimental device is not perfect enough to support the experimenter to debug strictly according to the theoretical optical path,the measurement results are inaccurate, and it is not conducive to cultivating students’rigorous academic attitude.In view of the above problems, a new young’s modulus experimental instrument is developed,and the angle detection device is introduced to realize the real-time measurement, display and debugging of the inclination of the optical lever plane mirror and ruler. and a new experimental scheme is compiled.The prototype is built and experimental verification is carried out The data error and experimental process are significantly improved.

The collection of atmospheric particulate matter samples is the basis of air pollution research such as comnonent analysis souree analysis.and toxicological ana ysis The traditional filter membrane samoling methoo has many shortcomings.Based on the theory of the droplet capturing fine particles, a set of wet trapping devices with three main structures including an atomization cavity,a mixing cavity and a water curtain cavity are built The device is used to conduct on-site sampling experiments on atmospheric particulates, perform microscopic imaging ana ysis on the colected solution sampes.and measure the seattered ignt intensity of the sampie solution to characterize the concentration change of the sample The experimental results show that the buil device can achieve effective collection of atmospherie particulate matter samples.

Using the falling-sphere method to measure the liquid viscosity coefficient is a basic experiment in college physics, which has attracted many attentions.The uncertainty of some measurement data in the experiment always exists,such as whether the initial velocity of the ball is zero, whether the measurement of the falling time is accurate, how to ensure the falling collimation,etc.,leading to some errors of the experimental results.Based on the possible error analysis in the experiment and the existing laser technology, we have made some improvements to the experimental instrument for measuring the liquid viscosity coefficient by the falling. sphere method, which greatly reduces the operation difficulty of the experiment.The results show that the improved experimental instrument can effectively reduce the experimental error and provide a feasible scheme for the accurate measurement of the liquid viscosity coefficient by the falling-sphere method.

A device for measuring the thermal expansion coefficient of solid by means of lever amplification is designed.The metal rod is heated to push the lever,and the ultrasonic displacement sensor is fixed at the other end of the lever.Based on the principle that the lever can significantly amplify the small elongation of the metal rod ,the small elongation of the metal rod is amplified to measure the small elongation of the metal rod.The data collection is programmed by Arduino to display the temperature and the amplified displacement in real time. Based on this instrument,the thermal expansion properties of solids can be studied and the thermal expansion coefficient of solids can be measured.The results show that the experimental phenomenon is obvious and the measurement results are accurate.The application of the instrument in physics experiment teaching can deepen students’understanding of the properties of solid thermal expansion and cultivate students ’ ability of innovative practice research.

Based on the image recognition technique, the nonlinear dynamic behavior of spring pendulum under two different control parameters is studied experimentaly.Power spectrum and maximum Lyapunov index are used to analyze and characterize the dynamic behavior quantitatively.The results show that under the experimental parameters,the transverse motion exhibits periodic vibration, while the radial motion exhibits quasi-periodic or even weak chaotic motion.It provides a good example for digital experiment of college physics.

Based on LabVIEW platform, a virtual instrument which can simulate process of Franck-Hertz experiment is developed.The virtual Franck-Hertz experiment instrument can simulate all the operation of the real instrument ,set parameters, give the 1-V value,and on the other hand recording data and drawing at the same time.We use the Monte Carlo method for the physical process of the experiment.The Franck-Hertz tube is divided into segments according to the flat free path of electron collision with argon atom, and the motion process of electron is simulated.Thus,the I-Vcharacteristics of Franck-Hertz tube are given.Because of the great amount of numerical simulation,real-time simulation of Monte Carlo algorithm based on the Labview is too time consuming to achieve.we save severa sets of real franck-Hertz experiment data. then mix them according to the parameters to simulate a Franck-Hertz experiment of measurement process,the result is well agreed with the real process.

Based on the interference principle of Newton’s rings, a simulation experiment software for measuring refractive index of liquid was designed and developed using Python programing language. The simulation software has a graphic user interface and functional modules including the introduction of experiment instrument and principle.the simulation of Newton’s rings patterns under different experimental parameters. the measurement of refractive index of common liquids,and data processing.It can also calculate and analyze the data of both virtual and real experiments.The simulation experiment software can be used to assist teaching. improve the quality of pre-class preview and the effect of teaching.

Quadrupole mass spectrometer is one of the important instruments for physics experiment teaching in colleges.A numerical simulation code based on the Python language was developed to simulate the trajectories of ions in quadrupole mass spectrometers.The code could simulate the trajectories of ions in quadrupole mass spectrometer under various kinds of conditions e.g.with different DC voltage U,radio frequency voltage Ve radio frequency voltage frequency w,and the ion’s charge-to-mass ratio m/z.The obtained ions’trajectories could be presented in form of images or animations to help students understanding the principle of quadrupole mass spectrometry better and enhancing the students’interest during the teaching process. In addition, this work lays the foundation for the implementation of teaching simulation experiments on the quadrupole mass spectrometry.

The experiment of measuring the coefficient of thermal expansion by Michelson interferometer is optimized based on the microcontroller technology.Firstly, the automatic recognition of Michelson’s interference fringe is realized by using the fringe recognition system ,then the automatic temperature measurement is realized by using the temperature detector,and finally the data calculation of the coefficient of thermal expansion is realized by computer programming.By introducing the microcontroller and computer programming technologies into the university physics experiment,the visualization of the experimental data and the intelligent calculation are realized, which makes the measurement and calculation of the coefficient of thermal expansion more convenient and faster.At the same time,the application of Michelson interferometer is expanded by applying the large object experimental equipment to the actual experiment.

Based on the physical principles of Hall effect and torque action, this proiect designs a set of laboratory safety intelligent management system by using steering gear,infrared sensor,Hall sensor,stepping motor,screw nut, rain sensing module,flame sensing module,buzzer and other equipment, single chip microcomputer control and bluetooth remote control.The device includes four systems;automatic door closing, automatic window closing remote lamp closing and flame detection. which can realize the functions of unmanned automatic door closing. detecting whether the doors and windows are closed.remote control dool closing rain detection. automatic window closing remote lamp closing flame alarm. etc The device has the advantages of simple operation, high automation ,stable system and wide application range.Through the test. the device can be widely used in various laboratories, has good adaptability to the environment, and is worth popularizing.

It is analyzed for the uncertainty of the measurement of small elongation based on traditional optical lever method.The results showed that the main cause of low measuring precision is the low accuracy of the scale and the intricacy for the operation.It designs a new experiment device based on optical power meter to monitor,which can simplify the operation and improves the accuracy of measurement.The experimental results have shown that the relative uncertainty of young’s modulus measurement up to 3.21%.

The main factors affecting the accuracy of Wheatstone bridge are the sensitivity of Wheatstone bridge and the error of resistance box.In order to simplify the problem and obtain semi qualitative, semi quantitative and approximate theoretical results,an approximate model of resistance error is established. Combined with the existing theoretical formula of bridge sensitivity, the theoretical values of bridge arm resistance Rand R, when the measurement accuracy is the largest (extreme) are derived by calculating the error minimum.In addition,some practical problems are analyzed and discussed in detail.Although the results obtained are approximate. the research ideas. methods and concusions may not only provide theoretica guidance for Wheatstone bridge experiment,but also provide some clues and references for relevant theoretical research.

For the experiment of free vibration ,the relationship between the amplitude θ of balance wheel and the natural period To can be expressed as θ＝ 10429－6525Ｔ0 according to the linear fitting function of Origin software,which can provide a clear reference for the analysis of subsequent experimental images. The experimental data of damping vibration and amplitude-frequency characteristic were processed by using the successive differential method and the graphic method respectively,and the obtained damping coefficients β are 0.0594 s-1 and 0.0610s-1.As for the forced vibration. the fitting results of amplitude-and phase-freouencr characteristic curves show that the resonance occurs when the motor frequency w is equal to the intrinsic frequency wn of balance wheel. the amplitude θr reaches 144°.and the phase difference (φ) between the balance wheel and the external force is just m/2.which well confirms the relevant rules of physical experiments.The resonant circular frequency can be calculated as w = 3.985 9 s by analyzing the characteristic parameters at resonance,and the relative error between w, and w(3.986 8 s)is only 0.023%, indicating that the graphical method is very successful in the quantitative analysis and calculation of the experimental data of forced vibration.

Based on the principle of damped vibration,the acceleration of spring vibrator is measured by smartphone.The damping coefficient and viscosity coefficient of liquid are calculated by the general solution of dynamic equation of damped vibration.The measured value of viscosity coefficient is compared with the theoretical value ,the relative error is 0.39 percent.The feasibility of this experimental scheme is demonstrated Compared with the traditional scheme,the method based on smartphone is easy to operate and interesting. Meanwhile,it reduces the instrument cost of traditional experimental methods,which has a certain reference significance for online teaching of physical experiments.

According to the optical refraction characteristic of transparent solid,the key problem encountered in the measurement of solid refractive index by laser speckle method is analyzed and discussed,and three kinds of optical measurement systems including near-field speckle,far-field speckle and image plane speckle are buil for measurement.Firstly,two speckle patterns before and after solid refraction are recorded,and then the small in-plane displacement before and after refraction can be obtained.Finally,the refractive index of solid is calculated according to the theoretical formula.Using the existing and improved methods, a comparative experimental study on the refractive index of 3 mm thick solid glass has been carried out through traditional holography and digital holography respectively.

Practical teaching is an indispensable educational content in science and engineering colleges.As an important basic experimental course, college physics experiment involves rich physical phenomena in mechanics, thermology,optics,electricity and magnetism and the measurement of relevant physical quantities. which“naturally”meets the needs of students to “learn in a wider range of professional intersection and integration”.In recent years,based on the platform of physics experiment teaching center,we have carried out reform and exploration on physics experiment in practical education from the aspects of practical teaching content and mode reconstruction, combination of science and innovation, promoting learning through competition,integration of industry, university and research, and achieved some teaching results and accumulated some experience.

According to the survey on the current situation of data processing teaching in physics experiment course,most students’data processing abilities are at a low level,which fails to meet the expectations.The problems are analyzed and the cognition change is deemed to be the first point to solve the problem.Based on the learning strategies and cognitive strategies , knowledge points about data processing are sorted out and well- organized to form a hierarchical and highly generalized knowledge framework.Experimental resources are also optimized.The teaching practice was carried out among certain students.The practical data shows that the students have made obvious improvements in the analysis of error causes,data processing methods and the formation of effective conclusions, which proves that the new teaching scheme helps to establish a good cognitive structure and improve their data processing ability.

With the advent of the“Internet +”era,hybrid teaching,as a new mode of teaching with the deep integration of information technology and educational teaching, has become a hot research topic in the reform of physics curriculum teaching in universities.The construction of a mixed teaching model of university physics courses will help to cultivate students’thinking style and hands-on ability,and thus become the high-quality talents needed for social development.lt expounds the necessity of the development of the university physics hybrid teaching model,analyzes the existing problems in the university physies teaching,and discusses the strategy of constructing the university physics hybrid teaching model.

In response to the national call for promoting the modernization of education mode in colleges and universities,and level of a new era of rapid development in science and technology in order to strengthen the management pattern of informatization, highly effective, Northeastern University physics experiment teaching center makes full use of modem information,on the basis of Internet technology,not only set up the experiment center of information management system.Moreover,through the network of course resources and the diversified teaching methods such as live broadcasting and virtual simulation, an efficient integrated management mode has been formed.It provides a good platform for the comprehensive talent training and comprehensive curriculum construetion of the school.

College physics experiment is an important part of basic teaching in higher education.Introducing physics history in college physics experiments is not only helpful for understanding the principles and laws of physics experiments,but also helpful for patriotism education.We show that introducing physics history and carrying out patriotism education are necessary in college physies experiment teaching.Further, we investigate the methods of patriotism edueation in college physics experiment teaching combined with physies history, as well as the problems that should be avoided.Patriotism education should be carried out timely, appropriately and moderately in college physics experiment teaching,and college physies experiment course should be built into the forefront of patriotism education.

With the development of Internet technology in China,online teaching mode has emerged,and the hybrid teaching mode combining online and offline gradually appears.In order to improve the teaching quality of liberal arts physics experiment course,this paper uses the Superstar platform , 0Q and wechat etc., combined with offline classroom teaching to explore the mixed online and offline teaching mode of liberal arts physics experiment.The practice shows that the mixed teaching enriches the teaching means, improves the teaching elfect and learning efficiency and provides an effective way for the reform of liberal arts physics experiment

teaching.