MathCAD软件在高等数学教学中的应用

本文介绍了 Math CAD的直观灵活的操作特点 ,通过实践和实例说明了它在高等数学课堂CAI教学中较之其它数学软件所特有的优势 .     

新型TBM刀圈材料微观组织及耐磨性能研究

TBM刀圈材料是一种对强韧性、耐磨性要求很高的合金钢材料. 目前常用的H13、DC53型TBM刀圈材料综合性能有待提高. 通过优化合金元素配比,制备出一种强韧型综合性能较好的新型TBM刀圈材料DB1,利用光学显微镜和扫描电子显微镜对DB1、H13和DC53的微观组织及断口形貌进行了观察分析,研究了不同载荷和不同硬度岩石条件下DB1与H13、DC53的磨损性能的差异,并对其磨损表面形貌进行扫描电子显微镜观察分析. 结果表明:一次碳化物的平均尺寸和含量对TBM刀圈材料的硬度、韧性及耐磨性有重要影响;适量的一次碳化物有助于提高材料的硬度及耐磨性;过多的一次碳化物会导致材料韧性急剧下降. 岩石抗压强度与刀圈具有匹配性,新型TBM刀圈材料DB1钢用于中等抗压强度的岩石时具有较好的耐磨性.      

Control of dispersion in fiber coupled resonator-induced transparency structure

Induced transparency phenomena and strong dispersion can be produced in a coupled resonator induced transparency(CRIT) structure.In this paper,we investigate the influences of structure parameters,such as amplitude reflection coefficient and loss,on transmission spectrum and dispersion of CRIT structure,and further study the control of dispersion in the structure.The results show that in the CRIT structure,adjusting the loss of resonators is an effective method of controlling dispersion and producing simultaneous normal and abnormal dispersion.When we choose approximate amplitude reflection coefficients of the two couplers,the decrease of transmittance due to loss could be effectively made up.In the experiment,we achieve the control of dispersion and simultaneous strong normal and abnormal dispersion in the CRIT structure comprised of fiber.The results indicate the CRIT structure has potential applications in optical signal processing and optical communication.     

A One-dimensional Coordination Polymer of Copper(Ⅱ) and Bis(4,6-dimethyl-2-pyrimidinethiolato)methane

Reaction of bis(4,6-dimethyl-2-pyrimidinethiolato)methane(bpytm) with CuCl2·4H2O in a mixed methanol/dichloromethane solution gave a one-dimensional coordina-tion polymer [CuCl2(μ-bpytm)]n which was characterized by single-crystal X-ray diffraction.It crystallizes in monoclinic,space group P21/c with a=16.9433(5),b=13.6986(4),c=7.8434(2),β=100.371(2)°,V=1790.71(9)3,Z=4,Mr=426.86,Dc=1.583 g/cm3,μ(MoKα)=1.751mm-1,F(000)=868,S=1.025,the final R=0.0399 and wR=0.0924 for 2538 observed reflections with Ⅰ2σ(Ⅰ) and 206 variables.The neutral coordination polymer is constructed by the bidentate thioether ligands to link adjacent copper atoms.Each copper atom is bridged by two adjacent nitrogen atoms of bpytm ligands and terminally bonded by two chloride atoms to form a squareplanar coordination geometry.The average Cu-N and Cu-Cl bond lengths are 2.025(2) and 2.234(1),respectively.     

角度调谐的多普勒激光雷达硬目标转速测量

利用角度调谐方法确定直接探测多普勒测风激光雷达的初始工作点,角度调节精度可达10 μrad.在此工作点处使用频率稳定性为10-7,单纵模出现概率大于98%的Nd:YAG激光器,通过偏振分光光路测得参考信号与回波信号.配合目标准确放置到准直镜的焦距上,分别测量了配合目标静止,正转和反转时的参考信号与回波信号.利用配合目标静止时测得参考信号与回波信号的关系可得参考信号的角度矫正因子为1.1949,使用该矫正因子测得硬目标在正转和反转时转速与真实转速之间的误差小于0.5 m/s.     

高等数学电子教案制作中软件的合理选用

本文概述了PowerPoint、MathCAD、MATLAB和3DSMAX软件的各自特点及它们在高等教学电子教案制作中的分工协作方法。     

基于有源Fabry-Perot腔的激光脉冲延时自外差研究

对注入有源Fabry-Perot腔内的单纵模脉冲进行了延时理论分析, 计算了Fabry-Perot腔内增益, 并对脉冲输出进行了数值模拟, 结果表明当脉冲能量衰减到一定值时, 新增抽运粒子数提供的增益可以补偿腔内损耗, 延时脉冲的输出可以达到稳态. 然后利用激光二极管侧面抽运Nd: YAG激光器做为Fabry-Perot腔, 对外部入射的单纵模脉冲光进行了延时, 得到了延时时间2 μups、脉冲数量140个的实验结果. 最后利用有源Fabry-Perot腔对参考光进行延时, 声光移频器对信号光产生频移, 进行了外差实验, 实验结果与移频器的设置值相符, 误差在4%以内.     

用MATLAB解决高等数学中的图形问题

本文通过实例将 MATLAB与 Mathematica的图形功能做了比较 ,指出了 MATLAB在解决高等数学图形问题时的优势 .     

刺老苞根皮干预大鼠骨折模型矿物元素含量变化

为探讨土家族药刺老苞根皮对大鼠骨折模型胫骨矿物元素的影响,将250只SD大鼠(雌雄各半)随机分成对照组、模型组和刺老苞根皮黄酮高、中、低(30、20、10 mg·kg-1)剂量组,每组10只,分别灌胃相应药物,每日1次,连续4周,用电感耦合等离子体质谱法(ICP - MS)测定了给药第4天、第7天、第14天、第21天和...