新升本科院校大学物理实验教学中心建设探索——以西安航空学院大学物理实验教学中心为例

大学物理实验教学中心是承担本科院校理工类专业基础教学的重要实验教学单位,新升本科院校通过高效的大学物理实验教学中心建设和高质量的大学物理实验课程实践教学的环节,培养适应地方经济建设发展需要的应用技术型人才。在理论及实验教学探索的基础上,通过西安航空学院大学物理实验教学中心的建设探索过程,提出了新升本科院校大学物理实验中心建设的思路途径,对新升本科院校大学物理实验教学中心建设具有一定的参考意义。     

开展学生“自拟方案的实验”的情况和体会

1、为什么要开展一些学生自拟方案的实验?从电工实验室投入使用以来,这两年的实验课都是学生依照老师编印好的实验指导书和配套好的仪器进行实验的.每个实验都是这样,没有例外.事实证明,这种方法对提高学生的实验能力、巩固理论教学的确能起到一定作用.特别是对初学者来说,这种实验教学方式可以说是不可缺少的.不过,我们组的老师在教学实践中逐渐感到只是单纯地采用这一种方式,还不能满足提高实验教学质量的要求.这是因为:     

《公差配合与技术测量》课实验改革的体会

实验教学是培养学生的动手能力,开发智力的重要途径之一,同时又是理论联系实际的重要手段。加强实践性教学环节、加强实验技能训练、培养学生独立工作能力和动手能力,是国家教委对我校套办专科学校的重点要求之一。 几年来,我们通过《公差配合与技术测量》实验课教学改革,取得了一些进展,对提高教学质量,加强学生的动手能力起了一定的促进作用,现就该实验课的改革与探索谈一些体会。     

工科高等学校实践教学质量的探索与实践

高等学校实践教学在整个教学过程中占有较大的比重,实践教学的质量将在很大程度上影响高校的教学质量和人才培养质量.因此,提高对实践教学重视程度,加大对实践教学环节投人力度,深化对实践教学环节改革,是提高实践教学质量的关键.     

刚体转动惯量的测量及数据处理

本文采用一元线性回归法进行刚体转动惯量实验的数据处理,对通常在测量中运用的简化条件作了分析,从而提高了实验课的教学水平,并使该实验具有实用价值。     

提高位式仪表控温精度的新方法——脉冲调宽式PID调节

位式控温系统结构简单,造价低廉,使用方便,控制功率大。大多数热处理炉都采用这种控温系统。但是,位式控温波动大,控温精底低。在位式调节仪表上加入校正环节可提高控温精度。钢铁研究院热工室马竹悟把他对这方面的研完成果发表在1959年第2期《仪器与实验技术》上。他采用两个时间常数不同的、与电炉同时加热的、正反串热电偶作为校正环节,来校正控温系统的惯性滞后而减小炉温波动(图1)。     

对《大学物理》课程教学改革的思考

简要论述了物理学教育的重要意义和当前《大学物理》教学改革的必要性,提出了《大学物理》课程教学改革的思路、设想和实践目标。教学改革的关键任务,是要提高学生的创新意识和综合应用能力。应以教学方法和手段的改革为课程改革的先导。对课程的内容体系框架的改革提出了建设性的设想,强调指出要加强近代物理教学,同时应调整和更新经典物理的教学内容;强调教学手段的改革是极为重要的,也是迫切需要解决的任务。还介绍了中国民航学院的《大学物理》课程正在着手实施的教学改革实践。     

《仓储管理》实践教学环节设计——以西安航专经管系物流管理专业实践教学为例

为提高高职高专院校物流管理专业实践教学环节的教学质量,结合我校的教学实际,分析在《仓储管理》实践教学环节中存在的问题。提出通过使用试用版商业软件、学生分组操作仓储设备和分析学校图书馆的仓储实践等方法来开展实践教学,提高物流业务操作能力,对实践教学具有一定的现实意义。     

试论高等数学教学与 CAI

阐述了ＣＡＩ在数学教学中的重要作用，以实例说明了在ＣＡＩ实验课教学中应注意的几个方面，并对目前数学ＣＡＩ教学所面临的问题进行了探讨     

电子仪器的维护及正确使用

电子仪器是泛指一切利用电子学原理测量的仪表、仪器、装置、系统和辅助设备。其中常用的有万用表、晶体管电压表、电子示波器、数字频率计、信号发生器和稳压电源等。电子仪器是由电阻、电容、电感、晶体管、集成块等各种电子元器件连接装配而成,特点是电路复杂,结构紧凑,定量准确度要求高,但受温度、湿度、电磁场等环境条件的影响较大。因此,对电子仪器的维护以及正确使用显得尤为重要。几年来从我们修理的仪器中常能见到这样的现象:有些仪器因长期不用或保养不善,使仪器发生漏电、击穿、甚至腐蚀断线等。还有的是因为使用不当,造成人为故障。比如,在修理中,发现大部分万用表都是因为测量时档位选择不对,造成测量事故。所以,认真做好电子仪器的日常维护及学会正确使用对延长仪器的正常使用寿命,减少仪器故障,保证安全生产和实验、教学工作的顺利开展都具有十分重要的意义。下面结合我们修理中发现的问题分别予以论述。     

Galileo Ultraviolet Spectrometer experiment

The Galileo ultraviolet spectrometer experiment uses data obtained by the Ultraviolet Spectrometer (UVS) mounted on the pointed orbiter scan platform and from the Extreme Ultraviolet Spectrometer (EUVS) mounted on the spinning part of the orbiter with the field of view perpendicular to the spin axis. The UVS is a Ebert-Fastie design that covers the range 113–432 nm with a wavelength resolution of 0.7 nm below 190 and 1.3 nm at longer wavelengths. The UVS spatial resolution is 0.4 deg × 0.1 deg for illuminated disc observations and 1 deg × 0.1 deg for limb geometries. The EUVS is a Voyager design objective grating spectrometer, modified to cover the wavelength range from 54 to 128 nm with wavelength resolution 3.5 nm for extended sources and 1.5 nm for point sources and spatial resolution of 0.87 deg × 0.17 deg. The EUVS instrument will follow up on the many Voyager UVS discoveries, particularly the sulfur and oxygen ion emissions in the Io torus and molecular and atomic hydrogen auroral and airglow emissions from Jupiter. The UVS will obtain spectra of emission, absorption, and scattering features in the unexplored, by spacecraft, 170–432 nm wavelength region. The UVS and EUVS instruments will provide a powerful instrument complement to investigate volatile escape and surface composition of the Galilean satellites, the Io plasma torus, micro- and macro-properties of the Jupiter clouds, and the composition structure and evolution of the Jupiter upper atmosphere.     

关于本科《机械制图测绘》教学方法的思考

测绘对提高学生的绘图能力、读图能力、查阅资料能力以及培养学生的工程意识和专业素质至关重要。机械制图测绘是《机械制图》课程非常重要的教学环节。针对我院刚刚由专科升为本科,教学理念、教学思路、教学方法都正在进行适当调整和改进这一实际情况,就我院工科类专业的机械制图测绘的教学思路和教学手段进行了思考,分析了制图测绘中存在的问题,提出了改进建议。     

The X-ray/Gamma-ray Spectrometer on the Near Earth Asteroid Rendezvous Mission

An X-ray/gamma-ray spectrometer has been developed as part of a rendezvous mission with the near-Earth asteroid, 433 Eros, in an effort to answer fundamental questions about the nature and origin of asteroids and comets. During about 10 months of orbital operations commencing in early 1999, the X-ray/Gamma-ray Spectrometer will develop global maps of the elemental composition of the surface of Eros. The instrument remotely senses characteristic X-ray and gamma-ray emissions to determine composition. Solar excited X-ray fluorescence in the 1 to 10 keV range will be used to measure the surface abundances of Mg, Al, Si, Ca, Ti, and Fe with spatial resolutions down to 2 km. Gamma-ray emissions in the 0.1 to 10 MeV range will be used to measure cosmic-ray excited elements O, Si, Fe, H and naturally radioactive elements K, Th, U to surface depths on the order of 10 cm. The X-ray spectrometer consists of three gas-filled proportional counters with a collimated field of view of 5° and an energy resolution of 850 eV @ 5.9 keV. Two sunward looking X-ray detectors monitor the incident solar flux, one of which is the first flight of a new, miniature solid-state detector which achieves 600 eV resolution @ 5.9 keV. The gamma-ray spectrometer consists of a NaI(Tl) scintillator situated within a Bismuth Germanate (BGO) cup, which provides both active and passive shielding to confine the field of view and eliminate the need for a massive and costly boom. New coincidence techniques enable recovery of single and double escape events in the central detector. The NaI(Tl) and BGO detectors achieve energy resolutions of 8.7% and 14%, respectively @ 0.662 MeV. A data processing unit based on an RTX2010 microprocessor provides the spacecraft interface and produces 256-channel spectra for X-ray detectors and 1024-channel spectra for the raw, coincident, and anti-coincident gamma-ray modes. This paper presents a detailed overview of the X-ray/Gamma-ray Spectrometer and describes the science objectives, measurement objectives, instrument design, and shows some results from early in-flight data.     

MIRO: Microwave Instrument for Rosetta Orbiter

The European Space Agency Rosetta Spacecraft, launched on March 2, 2004 toward Comet 67P/Churyumov-Gerasimenko, carries a relatively small and lightweight millimeter-submillimeter spectrometer instrument, the first of its kind launched into deep space. The instrument will be used to study the evolution of outgassing water and other molecules from the target comet as a function of heliocentric distance. During flybys of the asteroids (2867) Steins and (21) Lutetia in 2008 and 2010 respectively, the instrument will measure thermal emission and search for water vapor in the vicinity of these asteroids. The instrument, named MIRO (Microwave Instrument for the Rosetta Orbiter), consists of a 30-cm diameter, offset parabolic reflector telescope followed by two heterodyne receivers. Center-band operating frequencies of the receivers are near 190 GHz (1.6 mm) and 562 GHz (0.5 mm). Broadband continuum channels are implemented in both frequency bands for the measurement of near surface temperatures and temperature gradients in Comet 67P/Churyumov-Gerasimenko and the asteroids (2867) Steins and (21) Lutetia. A 4096 channel CTS (Chirp Transform Spectrometer) spectrometer having 180 MHz total bandwidth and 44 kHz resolution is, in addition to the continuum channel, connected to the submillimeter receiver. The submillimeter radiometer/spectrometer is fixed tuned to measure four volatile species – CO, CH₃OH, NH₃ and three, oxygen-related isotopologues of water, H₂ ¹⁶O, H₂ ¹⁷O and H₂ ¹⁸O. The basic quantities measured with the MIRO instrument are surface temperature, gas production rates and relative abundances, and velocity and excitation temperature of each species, along with their spatial and temporal variability. This paper provides a short discussion of the scientific objectives of the investigation, and a detailed discussion of the MIRO instrument system.     

The VIR Spectrometer

The Dawn spectrometer (VIR) is a hyperspectral spectrometer with imaging capability. The design fully accomplishes Dawn’s scientific and measurement objectives. Determination of the mineral composition of surface materials in their geologic context is a primary Dawn objective. The nature of the solid compounds of the asteroid (silicates, oxides, salts, organics and ices) can be identified by visual and infrared spectroscopy using high spatial resolution imaging to map the heterogeneity of asteroid surfaces and high spectral resolution spectroscopy to determine the composition unambiguously. The VIR Spectrometer—covering the range from the near UV (0.25 μm) to the near IR (5.0 μm) and having moderate to high spectral resolution and imaging capabilities—is the appropriate instrument for the determination of the asteroid global and local properties. VIR combines two data channels in one compact instrument. The visible channel covers 0.25–1.05 μm and the infrared channel covers 1–5.0 μm. VIR is inherited from the VIRTIS mapping spectrometer (Coradini et al. in Planet. Space Sci. 46:1291–1304, 1998; Reininger et al. in Proc. SPIE 2819:66–77, 1996) on board the ESA Rosetta mission. It will be operated for more than 2 years and spend more than 10 years in space.     

The Analyzer of Space Plasmas and Energetic Atoms (ASPERA-3) for the Mars Express Mission

The general scientific objective of the ASPERA-3 experiment is to study the solar wind – atmosphere interaction and to characterize the plasma and neutral gas environment with within the space near Mars through the use of energetic neutral atom (ENA) imaging and measuring local ion and electron plasma. The ASPERA-3 instrument comprises four sensors: two ENA sensors, one electron spectrometer, and one ion spectrometer. The Neutral Particle Imager (NPI) provides measurements of the integral ENA flux (0.1–60 keV) with no mass and energy resolution, but high angular resolution. The measurement principle is based on registering products (secondary ions, sputtered neutrals, reflected neutrals) of the ENA interaction with a graphite-coated surface. The Neutral Particle Detector (NPD) provides measurements of the ENA flux, resolving velocity (the hydrogen energy range is 0.1–10 keV) and mass (H and O) with a coarse angular resolution. The measurement principle is based on the surface reflection technique. The Electron Spectrometer (ELS) is a standard top-hat electrostatic analyzer in a very compact design which covers the energy range 0.01–20 keV. These three sensors are located on a scanning platform which provides scanning through 180^∘ of rotation. The instrument also contains an ion mass analyzer (IMA). Mechanically IMA is a separate unit connected by a cable to the ASPERA-3 main unit. IMA provides ion measurements in the energy range 0.01–36 keV/charge for the main ion components H⁺, He⁺⁺, He⁺, O⁺, and the group of molecular ions 20–80 amu/q. ASPERA-3 also includes its own DC/DC converters and digital processing unit (DPU).     

ATS-6 Synchronousi Orbit Trapped Radiation Studies with an Electron-Proton Spectrometer

The University of Minnesota Electron-Proton Spectrometer Experiment consists of two nearly identical detector assemblies. One of these assemblies was mounted in a position fixed on the satellite in the Environmental Measurements Experiments (EME) east direction and the other was rotated so that the spectrometer scanned a range of spatial directions covering 1800 from EME north to EME south through west. Each of the detector assemblies is a magnetic spectrometer containing four gold-silicon surface barrier detectors. This instrument provides a very clean separation between protons and electrons by the combination of pulse height analysis and magnetic deflection. Each detector assembly measures protons in three nominal energy ranges (30-50 keV), (50-160 keV), and (120-514 keV). Electrons also are measured in three energy intervals (30-50 keV), (150-214 keV), and (more than 500 keV). Data are transmitted from the experiment at rates as high as 8 measurements/s. Decreases in the flux of the energetic electrons and protons followed by very rapid increases are frequently observed on the nightside during periods of geomagnetic activity. Separation of temporal and spatial effects is possible using proton gradient information obtained when the detector systems are oppositely directed. Using this technique, the decreases have been interpreted as motion of the trapping region equatorward and Earthward of the satellite. The boundary motion associated with the particle recovery shows a marked local time dependence. Particle increases observed in the evening sector have been interpreted as motion from Earthward and equatorward of Applications Technology Satellite-6 (ATS-6).     

Ultraviolet spectrometer experiment for the Voyager mission

The Voyager Ultraviolet Spectrometer (UVS) is an objective grating spectrometer covering the wavelength range of 500–1700 Å with 10 Å resolution. Its primary goal is the determination of the composition and structure of the atmospheres of Jupiter, Saturn, Uranus and several of their satellites. The capability for two very different observational modes have been combined in a single instrument. Observations in the airglow mode measure radiation from the atmosphere due to resonant scattering of the solar flux or energetic particle bombardment, and the occultation mode provides measurements of the atmospheric extinction of solar or stellar radiation as the spacecraft enters the shadow zone behind the target. In addition to the primary goal of the solar system atmospheric measurements, the UVS is expected to make valuable contributions to stellar astronomy at wavelengths below 1000 Å.     

Regolith X-Ray Imaging Spectrometer (REXIS) Aboard the OSIRIS-REx Asteroid Sample Return Mission

The Regolith X-ray Imaging Spectrometer (REXIS) is the student collaboration experiment proposed and built by an MIT-Harvard team, launched aboard NASA’s OSIRIS-REx asteroid sample return mission. REXIS complements the scientific investigations of other OSIRIS-REx instruments by determining the relative abundances of key elements present on the asteroid’s surface by measuring the X-ray fluorescence spectrum (stimulated by the natural solar X-ray flux) over the range of energies 0.5 to 7 keV. REXIS consists of two components: a main imaging spectrometer with a coded aperture mask and a separate solar X-ray monitor to account for the Sun’s variability. In addition to element abundance ratios (relative to Si) pinpointing the asteroid’s most likely meteorite association, REXIS also maps elemental abundance variability across the asteroid’s surface using the asteroid’s rotation as well as the spacecraft’s orbital motion. Image reconstruction at the highest resolution is facilitated by the coded aperture mask. Through this operation, REXIS will be the first application of X-ray coded aperture imaging to planetary surface mapping, making this student-built instrument a pathfinder toward future planetary exploration. To date, 60 students at the undergraduate and graduate levels have been involved with the REXIS project, with the hands-on experience translating to a dozen Master’s and Ph.D. theses and other student publications.     

MESSENGER and the Chemistry of Mercury’s Surface

The instrument suite on the MErcury Surface, Space ENvironment, GEochemistry, and Ranging (MESSENGER) spacecraft is well suited to address several of Mercury’s outstanding geochemical problems. A combination of data from the Gamma-Ray and Neutron Spectrometer (GRNS) and X-Ray Spectrometer (XRS) instruments will yield the surface abundances of both volatile (K) and refractory (Al, Ca, and Th) elements, which will test the three competing hypotheses for the origin of Mercury’s high bulk metal fraction: aerodynamic drag in the early solar nebula, preferential vaporization of silicates, or giant impact. These same elements, with the addition of Mg, Si, and Fe, will put significant constraints on geochemical processes that have formed the crust and produced any later volcanism. The Neutron Spectrometer sensor on the GRNS instrument will yield estimates of the amount of H in surface materials and may ascertain if the permanently shadowed polar craters have a significant excess of H due to water ice. A comparison of the FeO content of olivine and pyroxene determined by the Mercury Atmospheric and Surface Composition Spectrometer (MASCS) instrument with the total Fe determined through both GRNS and XRS will permit an estimate of the amount of Fe present in other forms, including metal and sulfides.