两个电磁学演示实验的再设计

利用简易装置对高中教材中的退磁和自感演示实验进行了再设计，介绍了演示方法，并对实验现象给出了解释。     

Na离子和Cl离子引起He原子直接多重电离过程的研究

利用2～8 MeV的Naq+、Clq+(q=2,3,4,5)轰击氦原子,对碰撞的直接多重电离过程进行研究.实验采用反冲离子-散射离子飞行时间符合技术,通过反冲离子飞行时间谱区分不同价态反冲离子;利用静电偏转和位置灵敏探测技术区分不同电荷态散射离子;结合CAMAC-PC多参数获取系统得到一定价态散射离子所对应的反冲离子电荷态分布谱;经分析该谱得到直接多重电离截面与直接单电离截面之比R21.讨论了R21随入射离子速度和电荷态的变化关系.     

[二苯并-18-冠(醚)-6]KC60奇异特性的核磁共振研究

报道了用［二苯并-18-冠（醚）-6］修饰的碱金属富勒烯作核磁共振测试的一些结果．这类碱金属富勒烯呈现的奇特物理特性，反映了材料在低于200K温度下的磁有序性及电子磁矩与核磁矩的强相互作用，使共振信号增强，亦反映了超分子化学能调控碱金属富勒烯的物理性能 关键词：     

闹羊花毒素Ⅲ400MHz二维 ~1H NMR的谱研究

闹羊花毒素Ⅲ的结构较为复杂,采用一维1~H NMR 技术难以对谱做明确的指定。本文通过结合使用400 MHz 1~H-1~H 偶合相关、远程增强型的 1~H-1~H 偶合相关和二维 NOE 技术,对标题化合物的1~H NMR 信号的归属问题作了研究,解决了除前人已明确指定的个别信号外的所有其余信号的鉴别和指定。并且,根据二维 NOE 的实验结果,对其相对构型作了证实。这些结果有助于此类化合物的结构和构型的测定。     

Multiple-State Storage Capability of Stacked Chalcogenide Films （Si16Sb33Te51/Si4Sb45Te51/Si11Sb39Te50） for Phase Change Memory

The multiple-state storage capability of phase change memory （PCM） is confirmed by using stacked chalcogenide films as the storage medium. The current-voltage characteristics and the resistance-current characteristics of the PCM clearly indicate that four states can be stored in this stacked film structure. Qualitative analysis indicates that the multiple-state storage capability of this stacked film structure is due to successive crystallizations in different Si-Sb-Te layers triggered by different amplitude currents.     

纳米级氧化铁的合成及其对六价铬的吸附性能研究

采用溶胶-凝胶法合成了纳米氧化铁,研究了合成条件,并采用TEM对产品进行了表征,测得产品的平均粒径为20-30nm.研究了纳米级氧化铁对Cr（Ⅵ）的吸附.在pH=3.0,吸附比为3.5×10-6:1×10-2（g/g）时,平均吸附效率为95.98％,最大吸附量为398.3μg Cr（Ⅵ）/g.采用2mol/LNaOH可完全洗脱纳米氧化铁所吸附的Cr（Ⅵ）,测定了回收后的纳米氧化铁对Cr（Ⅵ）的吸附效率,结果表明纳米级氧化铁可循环使用,这将为环境污水中Cr（Ⅵ）的治理及研究纳米材料的吸附行为提供参考.     

Chaos Synchronization Criterion and Its Optimizations for a Nonlinear Transducer System via Linear State Error Feedback Control

Global chaos synchronization of two identical nonlinear transducer systems is investigated via linear state error feedback control. The sufficient criterion for global chaos synchronization is derived firstly by the Gerschgorin disc theorem and the stability theory of linear time-varied systems. Then this sufficient criterion is further optimized in the sense of reducing the lower bounds of the coupling coefficients with two methods, one based on Gerschgorin disc theorem itself and the other based on Lyapunov direct method. Finally, two optimized criteria are compared theoretically.     

波罗的海运价指数与样本航线期租的协整关系研究

波罗的海运价指数BD I是综合反应干散货航运市场运价总水平的指标,在众多的运价指数中占有公认的主导地位。本文以BD I运价指数为研究对象,通过协整研究,证明了BD I运价指数与BC I4条样本航线期租价格之间稳定的联动关系,并且给出了它们的误差修正模型。     

A MEMS-Based Piezoelectric Power Generator for Low Frequency Vibration Energy Harvesting

A novel power generator has been achieved to convert vibration to electrical energy via the piezoelectric effect. The generator obtained by micro fabrication process mainly consists of silicon based frame and composite cantilever. The prototype tested at resonant vibration generates 1.15μW of effective power to a 20.4-kΩ resistance load. The potential of this work is to offer miniaturization solutions for power generators, and with the proposed method the ambient ubiquitous vibration can be harvested effectively as endless energy source to form an integrated self-powering system.     

a-Si:H掺杂机理的研究

本文利用CNDO/2量子化学理论方法,对P和B原子在四面体配位的Si₄₆和Sl₄₆H₆₀H₄^*原子集团中置换Si原子前后的原子集团能量和能态分布变化进行了计算.计算结果表明:1)在Si₄₆H₆₀H₄^*原子集团中用P(或B)置换引Si原子后在能隙中明显地出现施主(或受主)态子带,同样在Si_{46相似文献}