Thermal radiation is an important aspect of experimental physics research.A spectrally selectivethermal radiation souree was fabricated based on metal-dielectrie-metal “ sandwich "metamaterial. "hemanufactured metamaterial source exhibited desirable thermal radiation feature according to experimental results , which revealed that thermal radiation energy has been foeused within a narrowband around the designedwavelength of 9.03 um with peak emissivity up to 98.09 and bandwidth of 1.58 μm.

The laser interference diagnosis system is built independently ,and the phase difference of two laserchannels is cealeulated by analyzing the interferenee image , and then the eleetron density is obtained from thephase difference.The rule of electron density variation with voltage at different positions and the distribution olaxial electron density at different voltages in eylindrical plasma discharge are studied by this diagnostic system.The experimental results show that the eleetron density inereases with the inerease of voltage at differentlocations ,and there is a plateau region of electron density in the increasing process , in which the electrondensity increases slowly with the increase of voltage.There is a density peak in the middle of the dischargetube.When the voltage exceeds a certain threshold,the number of density peaks changes from one to two , andthe electrons accumulate in the area near the anode to a certain extent.

ln the infrared communication characteristic experiments, the optical constants of materials can beobtained by measuring the relleetivity and transmissivity. However, the existing approximate solution methodshave errors ,and therefore the experiment can only measure materials with small or large attenuation.To solvethis problem ,the analytical solution is obtained by solving the equations,The extinction coeficient , attenuationcoelicient and relractive index of the material can be direelly ealculated from the analytieal solution. Theimproved calculation method has greater universality.

Several faults in the crystal electro-optic modulation experiment are analyzed and solved to deepenthe understanding and application of polarized light and nonlinear optics.Firstly,the problems of output signalcan be mostly attributed to the light path which is not turned to optimization.A preliminary judgment should bemade by observing the interferenee pattern, and then the light path can be adjusted by the rule of “two paralleland one orthogonal".Secondly ,the output voltage inerement AV is proportionate to the intensity of the ineidenlight / ,but inversely proportional to the modulation signal amplitude.Accordingly,the increment of the outputvoltage can be elfectively controlled within a reasonable range."Thirdly, when the polarizer and deteetor areparallel, the output voltage will not increase with the increasing bias voltage but decrease.

Regarding the issue of insufficient study on both theoretical and experimental teaching of lightbirefringenee phenomenon in our university ,the phenomena of linear polarized light ,elliptically polarized lightand cireular polarized light passing through the iceland crystal were studied to effectively integratebirefringenee experiments with polarization experiments of light, based on the experiment of polarization ollight,The study on light birelringence experiment not only helps to lear difficult knowledge, but also helps toexpand knowledge and cultivate ,improve the abilities of observation ,thinking and operation.

Funetional polymer materials are usually made of thin films, and the conduetivity measurement ofthin-film funetional polymer materials requires DC, three-electrode , Wheatstone bridge and DC four-probemethods, but these methods have certain requirements on the size and thickness of the sample.The fowdirection and distribution of DC current under different thicknesses are not controllable , which will seriouslyaffeet the test aecuraey. Moreover , the four-probe method is eomplicated to measure thin film materials,and it isnecessary to prepare square film first and fix it flat on the horizontal glass plate.Based on the above methods .anoriginal measuring device is proposed , and a set of measuring device for measuring the electrical conduetivity olfunetional Eeollex thin film materials is construeted by using the contaet separation 'TENG.The average relativeerror is 9.27296 , which fills the gap in the measurement of electrical conductivity of Ecollex materials, The innovation of the Ecollex film material conductivity measurement device lies in the contact separation TENGmeasurement funetion 'The advantages of Eeollex film conductivity are that the displacement current based AClest has no strict requirements on the geometry of the sample, and no specific shape is required, easy tooperate ,and can be in-situ detection.In addition, we provide a plantar energy harvesting scheme that can beused for the conversion of mechanical energy to electrical energy.

Based on the relationship between the volume of metal valence electrons occupying k space and thevolume of the Brillouin zone , the radius of the Fermi sphere was calculated, and the formula for calculatingelectron mean free path was derived, Taking Ag and Cu as examples, the electron mean free path wascalculated, which was consistent with the results obtained by other methods.When the geometric scale of metalmaterials was equivalent to the electron mean firee path , the physical properties related to it would undergo significant changes, From this perspective ,the critical values of Ag and Cu nano size were estimated using theaverage free path seale of electrons to be 52 nm and 39 nm , respectively.This caleulation approach was alsoapplicable to other metal nanomaterials.

To eultivate innovative talents who have innovation awareness and practical ability, college physiesexperimental projeets require a combination of basie experiments , comprehensive experiments, and innovative experiments. These experiments respectively improve practical abilities and thinking ability , enhance creativityand seientifie literacy , and strengthen innovation awareness and a comprehensive quality.The experiment olequal thickness interference of light is taken as an example, combined with the Lambert-Beer law,lt exploresthe relationship between the absorbanee and refractive index of funetional materials.This composite experiment transforms the results of scientilfie research projeets into undergraduate experimental teaching content.It canenhance the comprehensiveness and frontiers of university physics experiments. Moreover, it can stimulatestudents’interest in seienee and enhanee their enthusiasm for participating in seientiie research projects.Furthermore , the students' ability and quality are improved through basie physies experiments.

Using the ATp9100 ground object spectral radiometer to measure typical materials , obtain theispectral rellectance images , and perform uncertainty calculations and comparative analysis,The average relativeuneertainty of various materials is caeulated to be below 6%; The phenomenon of “ homochromaticmetamerism” was verified through test data, and the results showed that objects with the same color. Theispectral rellectance may also vary.lt leads to the latest progress and development trend of hyperspectral stealthteehnology,integrating scientifie research content into teaching work.

Aiming at the problems such as low measurement aceuraey of the existing Hall Angle sensors ,basedon the exploration of the of Hall elfect prineiple and the relation between Hall voltage and magnetie fielddirection,an Angle sensor based on Hall elfect is designed. We have self.made a small Helmholtz coil toprovide a stable magnetie field, fixed the Hall probe on a support frame, and achieved high-precisionmeasurement of the angle by measuring the Hall voltage after the Hall probe rotates at different angles.Themaximum measurement error is 0. l° when the rotation angle is not more than 75°.The sensor is applied toexplore the compound pendulum motion , obtaining the image of the relation between angular displacement andtime , achieving aecurate measurement of the motion state of the compound pendulum.The error between themeasured swing period and the theoretical value is only 2.0%6 , proving that the device can achieve high-precision angle measurement with fast response.

In order to make the measurement of the p-V curve and the overall process of calculating theefliciency of the heat engine from the curve an easy to operate part of university physics experiments , the autholfirst built the PASCO 'Tracker experimental system,Then , under two high temperature heat source temperaturesthe measurement of the p-t and V-t relationship curves in the operation of the heat engine was praeticed usingthis system , and based on this, the p-Y curve was obtained. After fitting the p-V relationship function , Therelationship between the efficieney of the thermal engine and the temperature of the high-temperature healsource ,as well as the mass of the steel wire loaded into the cylinder, was obtained through the caleulation of theprineiple formula.'The measurement results indicate that the period of pressure and volume both deerease withthe inerease of steel wire mass , while the ellicieney inereases with the inerease of steel wire mass.The two havea non-linear relationship.The elficieney of the thermal engine inereases with the inerease of the temperature ofthe high-temperature heat source.This experimental system can be used to demonstrate real-time monitoring olhe working process of a heat engine and to measure and calculate the eliciency of the heat engine.

Sodium benzoate in soy sauce was detected using surface-enhanced Raman spectroscopy ( SERS )and silver sol as the reinforcement substrate.In the first step,silver sols prepared with different concentrationsof sodium citrate were used to test the elfeet of their dose on SERS signal; In the second step, the Ramancharacteristic peaks of sodium benzoate at 848 cm~' ,1 012 em"' and 1 603 em"' were determined by comparingthe SERS spectra of the sodium benzoate standard and its solution and sample solution.In the last step, theSERS speetra of sodium benzoate samples in 12 different mass concentrations of soy sauce were collected ,andthe model established by univariate linear regression was analyzed.The results showed that SERS technologyusing silver colloidal as the substrate could be used for rapid quantitative detection of sodium benzoate eontent1n Soy SauCe.

Seientifie research achievements are integrated into the teaching of experiment, and a researchexperiment “ synthesis and characterization of upeonversion luminescent nanomaterials” is developed for theundergraduate students. Y,O, : Ybs* , Hos* upconversion luminescent nanomaterials are prepared using ahomogeneous precipitation method. The strueture , morphology , and luminescent properties of the materials arecharacterized by X-ray diflraction , transmission electron microscopy , and upeonversion emission spectroscopy.The influenee of particle size on the luminescent color is analyzed.The experiment includes research hotspotssuch as the preparation of nanomaterials and the study of upeonversion luminescence properties , involving theinter disciplinary fusion of the knowledge in physics, chemistry and materials.This experiment helps to stimulatestudents’ interest in the research of lumineseent materials and nanomaterials, deepen their understanding inmaterial synthesis methods and luminescent processes, not only expand their horizons and thinking, but alsostrengthen their comprehensive experimental skills.

In the Young's modulus experiment by classical tensile method,a position sensitive device is used toconvert the tiny elongation of the metal wire to the change of voltage signal.The voltage signal is amplifed bythe amplifier circuit ,and sent to the computer for real-time data acquisition with the data acquisition card , thenthe digital measurement of Young's modulus is realized.The new devices and technologies of modem seientiieand technological measurement are used,and the hardware and software in traditional physics experiments areintegratedl, and representative least square linear fitting and suecessive difference method for experimental dataprocessing are designed in this experiment,The measurement results are reliable and the experiment can beused as a typical comprehensive physics experiment for teaching promotion.

The precise electronic structure of the ground state of C,N, molecular system is studied by high-precision quantum mechanical calculation method, its isomerization potential energy surface is constructed, andits reaction mechanism is analyzed.The obtained results are helpful to the interstellar exploration and laboratorypreparation of C,N,and its related molecules in the future.

A sound velocity measurement method based on distributed fiber optic acoustic sensing is proposedby using the sensitive property of ultra-weak fiber grating to vibration.The speed of sound is calculated bymeasuring the time dillerence of sound signals received by different ultra-weak fiber grating sensors during thesound speed transmission process.T'he method can measure the speed of sound at different temperatures with anerror of less than 0,59 between the measured and theoretieal values.lt provides a new method for soundvelocity measurement.

A device for reeording parabolie trajectories using the magnetie adsorption principle is designed bymethods such as multi-sereen method, technical contradietion, and the ideal final result in the theory olinventive problem solving, ( TRIZ ) .It is suitable for teaching or home autonomous learning and does not requireeleetric drive.lt is a parabolic trajectory recorder that causes the target ball to move on a vertical plane throughspheres collisions at different angles , and the magnetic force of the target ball adsorbs iron powder particlesattached to the frosted coordinate plane to form a continuous parabolie trajectory.It has the characteristics oleombination ,portability , and versatility.

A vertical oseillation model of a single oscillating buoy wave energy converter was established basedon the potential flow theory.The numerical solutions of the motion equations were obtained using the RungeKutta algorithm in MATLAB.By means of numerical integration ,the average electrical power generation of thedevice was studied under different wave frequencies and damper damping coelficients,The results indicate thatunder the action of regular linear small-amplitude waves, the buoy and pendulum undergo small-amplitudeperiodie reeiprocating motions.'The relative motion of buoy and pendulum can drive the damper to performwork , thus realizing energy conversion and output funetions. Additionally, this study found that both wavefrequency and damper damping coefficient significantly affect the electrical power generation of the device.When the wave amplitude is l m and the frequeney ranges from 1.4 s~' to 2.2 s~' ,the average output power ofthe single oscillating buoy wave energy converter varies between 20 W and 300 W, These findings of thissimulation study provide important guidance for the performance optimization and regulation of wave energyconverters.

The teaching reform concept of“student -centered"(SC )involves three aspects : studentdevelopment centered, student leaning centered ,and learning elect centered.lt took the superposition of wavesin Physics Optics as an example to design a personalized virtual simulation experiment project to stimulatestudents' curiosity ,encourage students to cooperate and actively learn ,and guide students from the comfort zoneto the development zone through thinking and exploration.With the deepening and completion of the project , thestudents learned in praetice , gained experience in project activities ,and changed their brains with experienee .so as to achieve the improvement of the ability and self-development. After the completion of the project, theieedback results of the questionnaire survey also showed that the innovative personalized simulation projeelstimulated the leaming enthusiasm of the students and got a high evaluation from the students , which providedbasis and support for the continuous improvement of teaching in the future.

As the virtual simulation experiment teaching enters the 2.0 stage, higher requirements are putforward for the development of the virtual simulation experiment platorm,The photoelectrie effect experimenthas the characteristics of strong speciality , knowledge learning and scientifie research exploration , which is ofgreat significance to the cultivation of innovative talents.Unity3D software is used to complete the developmentof the virtual simulation experiment of photoelectrie elfeet,The writing and driving of C #f seripting language arecompleted in Visual $tudio development tools. The distribution law of experimental data is characterized byvisual learning analysis ,presenting a clear and intuitive physical quantity correlation,furthermore , it has alsorealized the development of pan-platform pan-terminal photoelectric effect virtual simulation experimentplatform, deepened the integration of physical space and virtual space , and promoted the transformation ofinnovative talent training from information to digitization,

lt constructs an experimental device for measuring Liquid concentration based on total rellectionprineiple. With the help of self-developed digital image processing technology,the angle is measured collectedby the high-definition camera, the refractive index of transparent liquid is obtained, The concentration iscalculated according to the Monotonie funetion relationship between the fiting liquid coneentration and itsrefractive index. The experimental prineiple is simple, the experimental deviee is easy to operate, and the aecuracy is high.The innovation ability of students has been cultivated in college physics study.

Based on matrix optics , the principles behind the formation of the hidden region in the near-axislight of a lens system were investigated.The inluenee of different lens parameters on the optical hidden regionwas explored. Through orthogonal experimental design , numerical simulations using MATLAB and COMSOLwere conducted to compare and visualize the factors affecting the hidden region.The research revealed that thefoeal length and radius of the lens have an impaet on the hidden region. When the diameter of the lens remainsconstant,the sum of the volumes of hidden regions t, and t, is minimized when the lens has a focal length of fAs the foeal length of the lens deereases below f,it is found that the focal length and the extent of the hiddenregion are negatively correlated. Conversely, when the focal length exceeds f, there is a positive correlationbetween the focal length and the extent of the hidden region. When the focal length ofthe lens remainsconstant ,there is a positive correlation between the diameter of the lens and the extent of the hidden region.Theorder of influence of various lens parameters on the volume of the hidden region is as follows: focal length f'>diameter h, > diameter h,> focal length f.These research findings are of great significanee in gaining

lmproving the power generation efficiency of photovoltaic batteries has always been the focus ofscholars' researeh.The MPPT technology guarantees that the photovoltaie power generation system continues towork near the maximum power point , thereby improving the efficiency of power generation. Ffaced with themulti-peak phenomenon of the P-U curve under uneven light ,it is diffieult for the traditional MPPT algorithmto find the maximum power point GMPP , which is easy to fall into the local peak point LMPp.In response tothe above problems , the simulation model of Simulink software is used to study the output characteristies of thephotovoltaic array under uneven light.It is hoped that the study will help and inspire the MPPT algorithm andthe arrangement of the photovoltaie array.

We selects the Hall effeet experiment course which is olfered by most colleges and universities inChina as an example,The combination of the two talent training eriteria of “teaching” and “educating people”in colleges and universities is taken as the guiding ideology.lt discusses the integration of curriculum thoughtand politics into the daily college physies experiment teaching,in order to produce "resonanee synergisticelfeet" with the ideological and political courses of other courses,'Through the effective integration of curriculumthinking and polities in the process of college physies experiment teaching,we can not only cultivate students'rigorous seientific attitude and the ability to solve practieal problems, but alo cultivate students' spirit ofdedication to seienee and patriotism. Finally achieve the goal of training undergraduate talents with innovativeprofessional physies knowledge application ability for the society.

Most textbooks on Semiconductor Physies laek an introduction to the application of basie theories inproduction practice and research frontiers, lf teachers strictly follow the content of the textbook, it is notconducive to cultivating students' ability to analyze and solve practical problems.In view of this ,it takes erystalsilicon solar cells as an example to explain how to intersperse the application of basie theories in productionpraetice and research frontiers in the teaching process of “Semiconductor Physics" , in order to stimulate students’interest in learning, improve their enthusiasm and initiative, and thus improve the teachingeffectiveness of the corse.

In order to overeome the mismatching dilemma between the hierarchieal teaching requirement in thelatest edition of the Basic Requirements for the 'Teaching of College Physics Experiment Courses in Science andEngineering Majors and current short suppling of teaching instruments, we explored a low-input and highefficieney autonomous hierarehical experimental teaching approach,Taking the autonomous and hierarchicaleaching pracice of Hall elect experiment as an example, it explores how to carry out C-level research experiment and D-level design experiment on the existing B-level experimental instruments.In the Hall elfeelresearch experiment , we evaluate the orders of all the effects and measure the additional potential caused by theside elfects.In the design experiment of Angle sensor, we have completed the experimental design of Anglesensor based on Hall elfect, and developed a set of two-parameter least square error processing method. Independent hierarchical experimental teaching is helplul to carry out experimental teaching reform accordingto its local conditions and improve the quality of experimental teaching.