Broadband mode converter and multiplexer based on dielectric-loaded plasmonic waveguides

We theoretically demonstrate a broadband mode converter and multiplexer based on plasmonic waveguides loaded with structured dielectrics. The proposed device can realize conversions between a fundamental TM₀ mode and a first order TM₁ mode, as well as (de)multiplex them with another TM₀ mode. Our design exhibits as wide as 400 nm bandwidth and as short as 6~7 μm coupling length. This work has potential application in high density photonic integrated devices for both computing and communication applications.     

Curvature investigation in tapered fibers and its application to sensing and mode conversion

Non-adiabatic tapered fibers are basic photonic components used in a wide range of applications. Here we investigate a way to increase their utility through the controllable bending of one of their tapered sections. The experiments carried out explain, for the first time, the mechanics of this approach showing how these tapers can be used to build more sensitive sensors. Their use as highly efficient mode converters is also discussed.     

Synthesis and biological evaluation of 5,6,7-trimethoxy- 1- benzylidene-3,4-dihydro-naphthalen-2-one as tubulinpolymerization inhibitors

A series of new combretastatin-A4 analogs were synthesized, in which a six-membered ring connects the linking bridge and A ring, and their tumor cell growth and tubulin-polymerization inhibitory activity were evaluated. These compounds appear to be potential tubulin-polymerization inhibitors. Compounds 1b with amino substituted on position 3 of B ring conferred optimal bioactivity, higher than that of the lead compound 22b and equivalent to that of CA-4. The binding modes of these compounds to tubulin were obtained by molecular docking, which can explain the structure-activity relationship. The studies presented here provide a new structural type for the development of novel antitumor agents.     

A numerical bifurcation study of friction effects in a slip-controlled torque converter clutch

Friction plays a key role in the efficiency and stability of the slip-controlled torque converter clutches. The effects of friction on the dynamics and stability of a slip-controlled torque converter clutch system using a bifurcation-analysis-based approach is presented in this paper. A three degree-of-freedom nonlinear driveline model with integral feedback action to control the clutch slip speed has been utilized for this study. The clutch interface friction is dependent on the slip speed and is a function of the static friction constant, μ ₀, the low velocity friction constant μ ₁, and the low velocity exponential rate, γ. Using one-parameter numerical continuation, local Hopf bifurcations of the subcritical type are observed as the friction parameters μ ₁ and γ were varied at low slip speeds. The continuation results are verified using simulations of the full nonlinear model. Stick-slip and undesirable oscillations of the model inertia elements are observed for certain parameter values. As the slip speed is increased, the bifurcation instability occurs at an increasingly higher value of μ ₁ signifying an improved tolerance of negative friction gradient at higher slip speeds. Smaller exponential rates γ are tolerated at higher slip speeds before the bifurcation instability occurs. For the range of parameter values considered, no bifurcations occur for a slip speeds higher than 3.4 and 4.5 rad/s with μ ₁ and γ as the continuation parameters, respectively. These values of slip speeds are much lower than the system’s first mode of torsional vibration of 16 Hz (≈100 rad/s).     

DL－32／16型多路时间间隔测量仪及其应用

基于模拟内插原理，研制了一种精密多路时间间隔测量仪。该仪器有一个公共起始通道和３２或１６路停止通道，测时范围５０ｎｓ～８２０ｍｓ，分辨力１ｎｓ，精度优于±５ｎｓ。由于采用了内部微处理器，仪器具有内部自检、通道识别、差错指示和测量数据自动显示，打印、处理及掉电保护等功能，并能给出多次测量的平均值、最大值和最小值。实验测量了Ｔ／Γ炸药的爆速和钨合金中的冲击波速度，得到满意的结果。     

基于轴角转换器的一种高精度动态测角系统

设计了一种基于轴角转换器AD2S80的高精度感应同步器动态测角系统，分析了测角误差产生原因，提出了误差调整和补偿措施。通过实例数据表明：用谐波分析的方法对测角误差进行了调整与补偿，从而可大幅度提高测角精度。     

基于智能数据采集器的研究与实现

针对目前各行业数字化、智能化产品应用日趋广泛，数据的获取、传输、分析、应用尤为重要，如何避免采集设备接口单一、功能固定、实用性差等缺点，提出采用ARM嵌入式工控模块M9080-N20为基础，采用VK3266串口芯片扩展UART串行接口，提出基于73K222AU调制解调器、HR219307变压器实现采集器二线模拟通信，并支持以太网、CAN总线和UART串行通信，可以有效解决数据远程采集、传输和控制，适用于特殊环境设备故障检测、诊断和抢修。实验结果证明，智能数据采集器不仅具有多种型号设备故障诊断功能；还能实现野外快速通信组网，不同类型设备数据远程采集、传输、分析和控制功能，在军民融合产品上具有广阔的应用前景和实用价值。     

An efficient synthesis of highly functionalized dinucleotide cap analogs

An efficient synthesis of new cap analogs containing aminoallyl linkers such as m⁷G[5′]pppp[5′]U-aminoallyl and m₂^7,3′OG[5′]pppp[5′]U-aminoallyl is reported. The final cap analog has been isolated with high purity (>99.8%) after ion-exchange column purification.