一种电感值和Q峰值可相互独立调谐的高线性有源电感

设计了一种电感值和Q峰值可相互独立调谐的高线性有源电感。该电感主要由跨导增强模块、互补共源级模块以及单端负阻模块构成。其中,跨导增强模块不仅可以作为正跨导器,并且可实现对电感值的大范围调谐；互补共源级模块不仅可以作为负跨导器,并且可改善有源电感的线性度；单端负阻模块不仅提高了Q值,并且补偿由电感值的调谐导致的Q峰值的变化。最终,通过以上模块的相互配合及其外部端口电压的协同调控,改善了有源电感的线性度,而且实现了在同一频率下Q峰值相对于电感值可大范围独立调谐以及在不同频率下电感值相对于Q峰值可大范围独立调谐的优秀性能。验证结果表明,该有源电感电感值的-1 dB压缩点为-7 dBm；在2.07 GHz的频率下,Q峰值可从240调节到1573,而电感值从11.89 nH仅变化到12.11 nH；在0.989 GHz、2.070 GHz和3.058 GHz的不同频率下,取得了493.7、501.2和508.4的高Q峰值,变化率仅为3%,而相应频率下的电感值分别为16.1 nH、13.4 nH和6.8 nH,变化率为136.7%。     

基于PDIUSBD12芯片的USB 接口实现方案

通用串行总线(USB)以其传输速度快、可靠性高、使用灵活等优点被广泛应用在PC外设和便携式系统中。PDIUSBD12是一种USB接口芯片。文章对PDIUSBD12的功能作了简要介绍，给出了一个由80C51和PDIUSBD12构成的USB接口电路的设计实例，重点介绍了其硬件电路和接口芯片的固件设计方法。     

Propriétés spectrales d’un laser semiconducteur soumis à une rétroaction optique externe

The rate equations of a semiconductor laser with external optical feedback are solved numerically. The method is applied to the case of simple optical feedback and to that of a high finesse external resonator. The spectral linewidth reduction, the damping of the relaxation oscillations and the influence of the resonant frequencies of the external resonator are discussed and compared for these two configurations.     

垂面排列液晶盒中不同电场表述的比较

从液晶连续体理论和动力学理论出发，分析了液晶盒中均匀场近似和非均匀场近似作用下的一般垂直和手性扭曲垂直液晶盒的动态响应特性。计算结果表明：在两种不同的近似情况下，液晶盒的响应速度是不相同的。使用均匀电场近似计算模拟比较简单、方便．计算速度快，可用作定性分析．但不能得到较准确的结果；使用非均匀电场近似更符合液晶盒内电场的真实分布，因此其对动态响应的计算结果更接近实际液晶盒的测试结果。     

Microwave-assisted one-pot synthesis of 3-substituted-3,4-dihydrocoumarins via tendem Konevenagel and Hantzsch reactions

A convenient route for the synthesis of 3,4-dihydrocoumarin derivates from salicylaldehyde derivates and 1,3-dicarbonyl compounds under solvent-free microwave irradiation conditions was described. In this way, a range of compounds was obtained in moderate to good yields in a short reaction time.     

用Zn/F离子先后注入和热退火法实现ZnO量子点的可控生长

将Zn/F离子先后注入到非晶二氧化硅中并分别在400,600,700 ℃下进行了退火.用光学吸收谱、透射电子显微镜(TEM)、高分辨透射电子显微镜(HRTEM)对退火的样品进行分析,发现在600 ℃退火后ZnO量子点已经形成.二次离子质谱仪(SIMS)测试发现在溅射时间为2 s时Si,Zn元素同时出现,说明没有在衬底的表面形成ZnO薄膜.从原子力显微镜(AFM)图像看到有少量的颗粒被蒸发到衬底的表面,说明在衬底的内部形成了ZnO量子点.F离子注入的作用为在衬底的内部形成ZnO量子点提供了O2分子.     

一种单片智能开关电源的设计

用FAIRCHILD公司开发的一种SPS智能 (或灵巧 )功率开关设计的一种 38V、3A的单端反激式开关电源 ,小型、轻便、廉价、高效与高可靠     

Hierarchical simultaneous entanglement swapping for multi-hop quantum communication based on multi-particle entangled states

Entanglement swapping is a key technology for multi-hop communication based on entanglement in quantum networks. However, the end-to-end delay of the traditional sequential entanglement swapping (SEQES) grows rapidly withthe increase of network scale. To solve this problem, we first propose a low-delay multi-particle simultaneous entanglementswapping (SES) scheme to establish the remote four-particle Greenberger–Horne–Zeilinger (GHZ) channel states for thebidirectional teleportation of three-particle GHZ states, in which the intermediate nodes perform Bell state measurements,send the measurement results and the Bell state type to the user node Bob (or Alice) through classical channel simultaneously. Bob (or Alice) only needs to carry out a proper unitary operation according to the information he (or she) hasreceived. Further, we put forward a hierarchical simultaneous entanglement swapping (HSES) scheme to reduce the classical information transmission cost, which is composed of level-1 SES and level-2 SES (schemes). The former is an innersegment SES, and the latter is an inter segments SES. Theoretical analysis and simulation results show the HSES can obtainthe optimal performance tradeoff between end-to-end delay and classical cost.