初中信息技术教学思考

信息技术教师不应该做教材的忠实传递者，而应该做课程的“设计者”和“开发者”.相较于其它传统学科教材，信息技术教材给了我们教师大得多的处理和发挥空间.通过不断的实践与充实，可以做出一些对学生发展有利的电子教材.教学中应以课程目标为最根本的出发点，选用合适的技术，应避免在使用传统教学手段能够取得良好效果的时候，生硬地使用信息技术.引用台湾学者徐新逸教授的一段话：“信息技术可以是一个工具、一位助手，却不能取代教师的地位而成为教学的全部，只要教师能抓住课程内容的重点，以最适当最有效的方式传达出来.     

灾害护理能力及其评价工具研究进展

世界范围内灾害频发,给人类带来难以预计的重创和损失。明确护士灾害护理能力、完善相关评价工具对于提升护士能力,提高灾害救援效果具有重大意义。现综述灾害护理能力相关概念、国内外灾害护理能力及相关评价工具研究进展。     

NONLINEAR DYNAMICAL BIFURCATION AND CHAOTIC MOTION OF SHALLOW CONICAL LATTICE SHELL

The nonlinear dynamical equations of axle symmetry are established by the method of quasi-shells for three-dimensional shallow conical single-layer lattice shells. The compatible equations are given in geometrical nonlinear range. A nonlinear differential equation containing the second and the third order nonlinear items is derived under the boundary conditions of fixed and clamped edges by the method of Galerkin. The problem of bifurcation is discussed by solving the Floquet exponent. In order to study chaotic motion, the equations of free oscillation of a kind of nonlinear dynamics system are solved. Then an exact solution to nonlinear free oscillation of the shallow conical single-layer lattice shell is found as well. The critical conditions of chaotic motion are obtained by solving Melnikov functions, some phase planes are drawn by using digital simulation proving the existence of chaotic motion.     

Measurements of charge transfer ef f iciency in a proton-irradiated swept charge device

Charged Coupled Devices(CCDs) have been successfully used in several low energy X-ray astronomical satellites over the past two decades. Their high energy resolution and high spatial resolution make them a perfect tool for low energy astronomy, such as observing the formation of galaxy clusters and the environment around black holes. The Low Energy X-ray Telescope(LE) group is developing a Swept Charge Device(SCD) for the Hard Xray Modulation Telescope(HXMT) satellite. A SCD is a special low energy X-ray CCD, which can be read out a thousand times faster than traditional CCDs, simultaneously keeping excellent energy resolution. A test method for measuring the charge transfer efficiency(CTE) of a prototype SCD has been set up. Studies of the charge transfer inefficiency(CTI) with a proton-irradiated SCD have been performed at a range of operating temperatures. The SCD is irradiated by 3×108cm-210 MeV protons.     

Direct Observation of High-Temperature Superconductivity in One-Unit-Cell FeSe Films

We prepared one-unit-ceil （1-UC） thick FeSe films on insulating SrTiOa substrates with non-superconducting FeTe protection layers by molecular beam epitaxy for ex situ studies. By direct transport and magnetic measurements, we provide definitive evidence for high temperature superconductivity in the 1-UC FeSe films with an onset Tc above 40 K and an extremely large critical current density fie Jc-1.7× 106 A/cm2 at 2K, which are much higher than Tc-8K and Jc-104 A/cm^2 for bulk FeSe, respectively. Our work may pave the way to enhancing and tailoring superconductivity by interface engineering.     

双光程光纤陀螺偏振误差模型与仿真

光路系统的偏振误差极大地制约着双光程光纤陀螺精度的提高。为了提高新型双光程光纤陀螺的精度,利用相干矩阵和琼斯矩阵对光路中光学器件和熔接点的光学参数进行描述,通过分析顺时针光波与逆时针光波中耦合次波列与主波列间的相干叠加机理,建立了相应的偏振误差模型。利用Matlab以接近于工程实际的参数设置,对光路系统中熔接点、各光学器件缺陷对偏振误差的影响进行了仿真分析,并在此基础上提出了一种可有效抑制双光程光纤陀螺偏振误差的尾纤匹配法。仿真结果表明,通过适当的尾纤长度匹配,双光程光纤陀螺的偏振误差由0.145°/h减小为0.017°/h,其随温度变化的峰谷值也由0.25°/h减小至3×10-4°/h,双光程光纤陀螺的偏振误差得到有效抑制。     

BEPCⅡ激光丝系统探测器模拟研究(英文)

BEPCⅡ上正在进行激光丝系统的研究。基于GEANT4对激光丝系统探测器进行了模拟。首先模拟了康普顿散射信号在探测器材料中电磁簇射的分布,确定了探测器初始尺寸。之后模拟了不同尺寸下探测器的输出,根据模拟结果确定了探测器的最终尺寸,使得探测器在所确定的尺寸有较大的信号输出。还进行了不同康普顿散射位置时探测器的响应模拟,结果表明束流管道的影响是不可忽略的,是探测器响应非线性的主要原因,预计该结果对束流截面测量有重要意义。最后简要介绍了BEPCⅡ几种可能的束流能量时,探测器信号输出和能量泄漏的模拟结果。     

重建彩色数字全息图时不同色光物光场的准确重叠研究

将数字全息检测物体表面视为散射面,球面波为参考波,使用角谱重建算法对不同波长照明情况下物平面光波场重建位置进行研究.结果表明,不考虑图像的物理意义时,衍射的一次傅里叶变换重建像中心与物光场频谱的中心相对应,以一次傅里叶变换重建像为参考,可以较好地确定物光场频谱位置,按照可变放大率的角谱重建算法实现不同色光重建场的准确重叠.     

关于空间型中的正螺面

将正螺面引入到一般的空间型中,在Beltrami-Klein坐标系下统一加以表示,并一致地详尽考察其度量、法向、第二基本形式及主曲率,推出正螺面是极小曲面.     

N-甲基哌嗪与乙酸乙酯、乙酸丁酯二元混合体系在298.15～313.15K的体积及黏度性质

测定了N-甲基哌嗪+乙酸乙酯和N-甲基哌嗪+乙酸丁酯2个二元混合体系在298.15,303.15,308.15和313.15 K的密度和黏度数据,并计算了N-甲基哌嗪+酯二元混合体系的超额摩尔体积(VEm)和黏度偏差(Δη),用Redlich-Kister多项式关联了二元体系的超额摩尔体积与组成的关系,用4个半经验公式关联黏度数据并关联了二元体系的黏滞性活化参数.结果表明,N-甲基哌嗪+乙酸乙酯和N-甲基哌嗪+乙酸丁酯二元体系在所测温度范围内的超额摩尔体积为正值,黏度偏差为负值,且二元混合体系在混合过程中焓驱动居于主导地位.