In the literature on solar cells , the relationship curve of output current versus output voltage and therelationship curve of output power versus output voltage are generally given. However, it is rare to see therelationship curve of output voltage versus load resistance ,the relationship curve of output current versus loadresistance , and the relationship curve of output power versus load resistanee. These curves are studiedexperimentally and theoretically here.The results of experimental tests and theoretical calculations are quiteeonsistent.Both of them show that , for a determined solar cell circuit, with the increase of load resistanee , theoutput voltage monotonically inereases and the output current monotonically decreases. However, the outputpower does not change monotonically ,there is an optimal power value.'This optimal power value corresponds toan optimal load resistanee value.In addition , we have also studied the impact of incident light intensity on theoutput voltage ,output current and output power of solar cells, and found that all these outputs increase with theinerease of light intensity.The results of this work are of great significance in the design and application of solarcell circuits.

The characteristic experiment of silicon solar cells is the study of the volt-ampere properties ofsilicon solar cell by means of circuit experiments.Conventional experiments do not fully take into account theelfect of the connection of the measurement apparatus on the measurement results , leading to anomalous datacurves and low elfieiency in practical operational experiments.We present three circuit connection methods forsilicon solar cell load testing and analyze the impact of different meter connection methods on the measurementresults.Students can understand the main points of photovoltaic measurement through the data processinganalysis and discussion of the experimental results. This experiment has cultivated the students ' ability toanalyze and solve problems.

Thermal radiation is a crucial topic in university physics education.It employs the dual-bandcolorimetry of thermal radiation and computer vision technology to successfully design and construct anexperimental apparatus for building a flame temperature field distribution model. The apparatus utilizes acomputer vision system to collect and match flame thermal radiation data in different spectral bands.Based onthe theory of dual-band colorimetry, the experimental data is processed to obtain the flame temperature fielddistribution model. Additionally ,an automated data acquisition and calculation program is developed using thePython language. 'Through this apparatus, the study delves into the impact of various factors on flametemperature and temperature field distribution. "he measured experimental data is employed to successfullyvalidate Planck's blackbody radiation law.lt is noteworthy that this apparatus received the first prize in the 9thNational College Student Physics Experiment Competition( Innovation )".

The UV radiation is both beneficial and harmful for human health ,but it not visible for human eyeso it needs to be detected. Among various types of UV detectors , photochemical type UV detectors have attractedmuch attention for their simple fabricated process , fast response speed ,low cost and self-powered and so on.lrthis work , commercial P25 nanospheres were scraped on FTO conductive glass substrate and assembledsandwich structure photochemical type UV detectors, Under the irradiation of 365 nm with 35 mW . cm^-2 , theopen circuit voltage of the deviee is 0.576 V, the short cireuit current density reaches 1.045 mA * cm^-2, theresponse rise time is 0.010 s and the recovery time is 0.01 s.Under the periodic ultraviolet irradiation , thedevice also shows a stable and reproducible switching performance.In addition ,the device still shows excellenvisible light blindness characteristics and linear input and output characteristics.

By utilizing the same polarity repulsion between permanent magnets, a magnetic potential well wasconstructed to design and manufacture an unfallable pole device with adjustable height and anti-slip bottomThe device exhibits strong anti-interference ability , good stability, simple structure, and clever design. Themagnetic constraint between permanent magnets does not require external power supply, and has advantagessuch as contactless control,energy conservation ,and low cost.

A broadband antirelective Si0, coating with high transmittance and good hydrophobicity in thevisible range was successfully prepared by template-free sol-gel method.The refractive indices of the bottomlayer and top layer of the coating are 1.34 and 1.15 , respectively. The bottom layer was prepared by mixing Si0sols catalyzed by acid and base, and the sol of the top layer was prepared by using hexamethyldisilazane( HMDS) as modifier, which is composed of trimethylsilanized Si0, nanoparticles. According to the design requirements of the optimized film system, suitable technological parameters were selected to prepare thedouble-layer coating. The test results show that the average transmittance of the Si0, double-layer coating in thevisible light region is 98.64%,and the static water contact angle can reach 134°.

We have designed an experimental method for three-dimensional sound souree localization using theattenuation law of sound intensity. Sound localization is mainly achieved by measuring the distance , directionand height of the sound source relative to the exploration center. Using the principle of logarithmic attenuationof sound intensity ratio , the relationship between the attenuation law of sound intensity in air and the distancefrom the sound source was derived ; A angular displacement method was designed to measure the direction olsound sources , and the relationship between the magnitude of angular displacement and the time when thesound intensity ratio reaches its peak was given ; The height of the sound source to the horizontal plane of thereference platform was measured using an electronie control lifting platform. And a three-dimensional soundsource positioning experimental device was made within a range of 1 cubic meter,The experimental resultsshowed that the maximum relative error of the sound source distanee measurement in the two-dimensional planewas 2.3% , and the maximum error of the azimuth measurement was l.6°; In three-dimensional space , themaximum relative error of sound source distance measurement is 2.9%, the maximum relative error of height measurement is 4.9%, and the maximum error of azimuth measurement is 0.8°.lt has been proven througlexperiments that the positioning effect of this experimental system is good.

Due to excellent physical and chemical properties , graphite materials have become a researchhotspot in the field of sensors in recent years.A probe device based on rectangular cantilever beam , temperaturecontrol box and hygrometer are designed.The performance of strain and temperature sensor based on graphitesheet is tested.The linearity and sensitivity coeficients of strain measurement are 0.978 and 0.001 96 /u8.respectively.The linearity and sensitivity coefficients of temperature measurement are 0.945 and 0. 052 67 Ω/℃ , respectively.At the same time , the influence of humidity on the performance of graphite sheet sensor isalso studied and it is found that there is a sharp threshold elfect of humidity on the conductivity of graph itesheet.When different strains are applied, the critical humidity value of electrical conductivity mutation is about7096.The results of this study show that if graphite sheets was utilized for strain measurements ,it is necessaryto setteled in an environment with humidity below 70%.

With the deepening of the research of vortex light , higher requirements are put forward for thetransmission control of vortex light in various media.The on-off control of vortex optical transmissioncompleted in the three-level heat source subsystem by using the optical pump effect. The transmissior transmittance of signal light is regulated by controlling the degree of detuning of signal light ,the optical poweof pump light and the temperature of rubidium atom gas pool, so as to realize the on-off control of vortex opticatransmission.lt combines theory with experiment , so that students can fully understand theoretical knowledgthrough experiment , and cultivate and improve students' practical ability and innovation conseiousness

A set of visual measurement platform for the elastic modulus of gold wire is designed. A set olinterferenee facula measure device is designed base on that principle of measuring the optical path differenceby using the interference method , and the micro deformation of the metal material in the stretching proces isaccurately measured.The machine vision method is introduced to realize the visual measurement of the sectionalarea of metal materials.The built transmission structure can continuously and stably apply the pulling force. The graphical operation interface developed for the platform makes the measurement process visualized, and thetensile change is verified by observing the displacement of material surface topography characteristics. Theplatform improves the experimental measurement accuracy , and the relative error of measurement results is 3.3%.The measurement platform can be used as a comprehensive experimental instrument in college physicsexperiment teaching.

Single-photon counting is the most sensitive weak light measurement technique , with widespreadapplications in biomedicine , basie physies researeh , making it an important experimental subjeet for the trainingof undergraduates in nuclear physies, nuclear technology, ete, ln practical applications, to reduce noiseinterference and extract time-correlated information, the coincidence method has been widely used in photoncounting technology .However , there is no coincidence-based photon counting teaching experiment equipment atpresent.In particular, the traditional photon counting teaching experiment equipment needs to be matched with a discriminator and coincidenee module , which inereases the cost and complexity of the experimental teaching.[herefore , in order to strengthen the understanding of photon counting measurement and coincidence principlea coincidence-based photon counter was developed based on Field-Programmable Gate Array ( FPGA ).Thecoincidence-pased photoncounterinstrument ,based on the traditional photon counting instrument, hasadded the function of dual-channelphoton coincidence measurement(countingandtmeinterva) and improved the light souree to a pulsed light souree modulated by transistor-transistor logie(TTL) signal through afilter,This makes the instrument not only meet the needs of traditional teaching experiment instruments , but alsoallows various expandable experiments to be designed based on the instrument.

Angular momentum and the law of angular momentum are key and diffieult points in college physicsteaching. lt introduces a self-made portable angular momentum demonstration instrument that integratesqualitative demonstration of the vectorization of angular momentum , qualitative demonstration and quantitativeverilication of the law of angular momentum conservation, and explores its application in classroom teachingThis teaching aid mainly consists of rotating dises ,ball piercing dises ,electric motors , variable speed controllersand other parts. The overall structure of teaching aids is compact, easy to carry and operate, and thephenomenon is very obvious.lt can visualize the vectorization of angular momentum and the law of angulalmomentum conservation , which is conducive to breaking through the teaching difficulties of concepts and lawsrelated to angular momentum and achieving efficient classroom generation.

Using the simplification of the experimental steps as a starting point, the photoelectric ellectlaboratory instrument is used to measure the refraetive index and conductivity of liquids.Combined with therelationship between different physical properties of liquids, the magnitude of photocurrent in differentconcentrations of the same liquid is measured. With the help of Origin software ,the equations of the calibrationcurves of photocurrent and liquid refractive index and conductivity were fitted. The refractive index andconductivity of the liquid can be calculated by substituting the magnitude of the measured photocurrent.

Aiming at the problems of low aeeuraey caused by uneven heat dissipalion and diferenees in heatdissipation coelficient between upper and lower surfaees of copper disk in the measurement deviee for them maleon duetivity of bad conduclors, an important comprehensive thermal experiment in universities , self-made watereireulation device with the help ofwater cooling exchanger. The deviee was improved by installing two 40 * 80 *10(mm) and five 40 * 40 * 10( mm ) cooling guide blocks at the boltom of the cooling dise to achieve uniommheat dissipation and colleet and process data.The results show that the first improved method is belter ,and theexperimental aecuracy has inereased by 9. 15 times. On this basis, based on the Seebeck effect ofsemieonduetors,the waste heat of heating disk and cooling disk was used to suecessfully change the latter fromload to power supply , and a green and environmentally friendly power generation mode - temperalure dilfereneepower generation deviee is designed, with the “light” of LED and the “ sound" of jasmine musie and the" futtering in the wind" of DC motor driven by fan blades blowing. And the volt ampere characteristie curves olthree types of load terminal voltages and temperature differenees , as well as linear and nonlinear components were analyzed.

Eddy currents oecur when the AC current flows through the RLC resonant cireuit, and the coiresistance will rise sharply as the AC frequency increases. Because the mechanism of skin and proximity effectsbetween single-core coils and multi-core coils is different ,the AC resistance of the two coils is diflerent with theinerease of AC frequeney.T'he relationship between resistance and AC frequency in single-core and multi-corewires was measured by the resonance method, and the eddy current losses of single-core and multi-core coilsunder difflerent AC frequencies were simulated and calculated , which showed that in the case of high-requency AC , the eddy current elfect of multi-core coils was higher than that of single-core coils,Experimental tests are inagreement with the calculated results.

In order to address the issue of data transmission errors in integrated cireuits caused by stronginterferenee in industrial environments and to achieve reliable communication in such conditions,an improvedand innovative intereaving and coding/decoding method is proposed based on the principle that errolcorreetion codes can enhance the integrity of essential data signal transmission. This method optimizes the UART protocol for high-reliability transmission , and utilizes CRC checksums and reliable encoding modules todetect and correct transmission errors in the data, thereby enabling integrated systems to better adapt tocomplex and dynamic industrial environments.Perormance testing of the improved interleaving and decodingalgorithm is conducted using Al signal aequisition as an example , demonstrating the algorithm's significanterror detection and correction capabilities for data transmission in strongly interlered environments.

In order to realize the positioning and precise detection of small objects such as electronic chips , twokinds of low distortion optical lens which can be used in machine vision are designed with Zemax software.Thefocal length is 28.5 mm,and the objeet field of view is 10 mm. A traditional refractive lens, with all sphericalsurfaces , consisting of six lenses with a total length of 90 mm is obtained through optimization design. At thespatial frequeney of 100lps/mm, the MTF of all fields of view is higher than 0.5 ,and the maximum distortion is -0.078%. 0n the basis , a refractive diffractive hybrid lens , consisting of four lenses, is further optimized.The total length is 75 mm, MTF is above 0.55 at the same spatial frequency ,and the maximum distortion of 0.071%Considering the influence of diflraetion efficiency of the diffraetive surface on MTF , the aetual MTF of themixed system is still higher than 0.52. Through simulation design, students can not only understand the designcharacteristics of machine vision lens .but also exercise their innovative ability.

Based on the Jones matrix analysis and through the objeet-oriented design of optical devices,virtual simulation experiment of polarized light with immersive experimental experienee, scientificallquantitative analysis , and dynamic display of polarization state patterns was created. The projeet can be used toassist physies experiment teaching or direetly carry out virtual simulation experiment teaching, which helps topromote experimental teaching reform and improve experimental teaching elfectiveness. The project proves thavirtual simulation experiments are an effective means of educational informatization.

The nonlinear dynamics of a simple pendulum is solved using lagrange equation,and the numericalsimulation is carried out with Python software. The influence of damping factor and torque drive on the motionof simple pendulum is investigated. The simulation results present the variation of the pendulum angle andangular velocity with time, the evolution of the phase trajeetory, and the chaotie phenomenon under strongdriving foree.

In the teaching of rigid body rotation, we first explain the moment of inertia of regular rigid bodyand then guide students to deduce the moment of inertia of cuboid rigid body. Then we propose how to measurethe moment of inertia of smart phones. We guide students to measure the moment of inertia of mobile phones byusing gyroscope sensor and phyphox software of smart phones , and get good results. 0n the one hand ,there is noneed for complex and huge demonstration instruments.Teachers and students can directly operate and measurein class. and students can also make measurement and calculation as homework alter class.0n the other handthis demonstration experiment integrates several knowledge points of rigid body motion,such as the calculationof moment of inertia of regular cuboid, the law of parallel axis and the rotation of rigid body. The above workprovides a beneficial attempt for the integration of smart phones into college physics demonstration teaching.

Based on the Kelvin bridge resistance measurement circuit, the digital measurement is realizedcombing coaxial resistance , PASCO system, micro signal amplifier and other instruments. While avoiding thecomplicated adjustment steps , the measurement error caused by the temperature change due to long-timepowered resistance to be measured is reduced. Compared with the standard value , the measurement error of theresistivity and temperature coefficient of resistivity of copper is small, which indicates that the method isfeasible to reduce the error caused by temperature change in the measurement process.

By analyzing the signiicanee and current situation of integrating the " eraftsmanship spirit” into theinnovation and entrepreneurship quality education of normal university students ( referred to as " the integrationof craftsman ’s spirit and innovation education " ), four elfeetive integration paths are explored, namelyexpanding the platform carriers of“the integration of craftsman’s spirit and innovation edueationconsolidating the teaching staff of“the integration of cratsman’s spirit and innovation educationstrengthening the value guidance of “ the integration of craftsman’s spirit and innovation education" , andcreating a good atmosphere of “ the integration of craftsman'’s spirit and innovation education".Research hasshown that only by promoting, inheriting, and practicing the spirit of craftsmanship in innovation andentrepreneurship practice can we elfectively cultivate innovation and entrepreneurship abilities , improvethequality of teacher education, raise the professional literacy of normal university students , and enhance theeffectiveness of innovation and entrepreneurship education.

The construction and development for elective courses of new engineering disciplines is discussed inthis paper,based on the general education thinking, and with “ Nano Materials and Devices” as an example. The course construction goals should be enriched and clarified, according to the academic and industrialdevelopment.The course knowledge systems should be reasonably derived. The course content should beorganized logically , distinctively and with an overall consideration. Intellectual education should be wellcombined with moral education by a multi-dimensional ideological and political teaching strategy ,for elevatingthe course education level. Furthermore, the course should be continuously improved to minimize the gapbetween “ teaching" and “learing” gradually, and better support student development.

College Physics Experiments is an important public basic course in science and engineering. Atpresent,the exploration of Problem Based Leaming( PBL) in this course is not sulicient ,and it is necessary todesign and practice it to further improve the teaching elfectiveness of university physics experiments. Byanalyzing the current teaching situation and the problems that need to be solved, the first step is to start withthe construction of the teaching staff, and solve the problems of teachers "ideological preparation andcollaborative cooperation. Then, taking the experiment “ Adjustment and Use of Speetrometer" as an example ,discuss the structure of course problems and the integrated design during all teaching stages before , in , andafter class. 'he results of the questionnaire survey indicate that the implementation of PBl, can enhaneestudents’ interest in learning and enhance teaching effectiveness. lt provides reference for the application ofPBL teaching mode in College Physics Experiments teaching.

In order to cultivate students’ critical and innovative abilities, and further enhance the “ genderequality" of physics experimental courses, based on the course opening and laboratory conditions , and referringto home experiments and experimental competition models, it studies the establishment of autonomouscomprehensive design experiment projects and content, further puts forward the establishment norms andprocedures,'Through research, optimizing the course content system can enhance the student team and

innovation ability.

Under the “new development" concept of adhering to the concept of cultivating virtue and talents.with the primary goal of cultivating innovative and outstanding talents, the physies experimental teachingplatform has been comprehensively restructured, and the goal of ideological and political construction has beenclarified in the physics experimental curriculum.The core of this refactoring is to divide the experimentalproject into five modules , each corresponding to a key capability requirement.The construction of these modules focuses on five aspects, namely“ moral cultivation ", “ global concern ", “ Zhejiang University spirit* patriotism" , and “ today's attention" .Finally , the details and measures of integrating ideological and politicalelements from five aspects were explained in detail through experiments with the Michelson interferometer.Theintegration of these elements not only helps students master experimental skills , but also greatly enriches theexperimental content, making the“ gender equality" of the course more prominent. More importantly , it cultivates outstanding talents with moral character, global perspective , Zhejiang University spirit , nationalsentiment ,and social responsibility.