长江江豚基因组大小测定

本研究采用流式细胞术,以公鸡(Gallusdomesticus)红血细胞DNA含量为标准,测定了23头长江江豚(Neophocaenaphocaenoidesasiaeorientali)的基因组大小(或称C值)。实验过程中采用了保存在3中不同条件下的长江江豚的全血样品,用3种不同的方法提取白细胞。为了获得本实验所用的公鸡红血细胞DNA含量的准确值,首先以人(Homosapiens)的C值为标准,对其进行了校正。然后其C值(2C=2.35pg)用于长江江豚的基因组大小测定。结果发现:长江江豚的单倍体DNA

圆形碘孢虫完整孢子ELISA的建立

探索建立鱼类寄生圆形碘孢虫(MyxobolusrotundusNemezek,1911,Myxosporea,Bivalvulida)完整孢子酶联免疫吸附试验(Enzyme linkedimmunosorbentassay,ELISA)检测的可行性,对丙酮、戊二醛、甲醛、多聚甲醛、乙醇等几种常用固定剂应用于此方法的效果进行评价,初步建立了针对鱼类黏孢子虫的完整孢子ELISA检测模式。结果显示,同比其他几种固定剂,2%的多聚甲醛、0 25%的戊二醛对圆形碘孢虫完整孢子ELISA有较好的效果,经二者固定后,最

Determination of the rheological parameters of self-compacting concrete matrix using slump flow test

The classification of a concrete mixture as self-compacting (SCC) is performed by a series of empirical characterization tests that have been designed to assess not only the flowability of the mixture but also its segregation resistance and filling ability. The objective of the present work is to correlate the rheological parameters of SCC matrix, yield stress and plastic viscosity, to slump flow measurements. The focus of the slump flow test investigation was centered on the fully yielded flow regime and an empirical model relating the yield stress to material and flow parameters is proposed. Our experimental data revealed that the time for a spread of 500 mm which is used in engineering practice as reference for measurement parameters, is an arbitrary choice. Our findings indicate that the non-dimensional final spread is linearly related to the non-dimensional yield-stress. Finally, there are strong indications that the non-dimensional viscosity of the mixture is associated with the non-dimensional final spread as well as the stopping time of the slump flow; this experimental data set suggests an exponential decay of the final spread and stopping time with viscosity. © Appl. Rheol.

Ultracompact triplexer by coupling and decoupling of multiple photonic crystal waveguides

We investigate numerically the self-imaging effect in a system of multiple coupled photonic crystal waveguides (M-CPCWs) with asymmetric coupling. Then two couplers of 2-CPCWs and 3-CPCWs are cascaded to form an ultracompact triplexer by employing coupling and decoupling of M-CPCWs. The wavelength of 1310 nm propagates along the input direction because the M-CPCWs are decoupled at the same decoupling frequency. The other two wavelengths (1490 and 1550 nm) are separated by combining multimode interference and the dual mode coupling effect. Only by introducing a single defect near the crossing point between two output photonic crystal waveguides (PCWs) are the high extinction ratios for the three wavelengths achieved simultaneously.

Proposal of an Ultracompact Triplexer Using Photonic Crystal Waveguide with an Air Holes Array

We propose an ultracompact triplexer based on a shift of the cutoff frequency of the fundamental mode in a planar photonic crystal waveguide (PCW) with a triangular lattice of air holes. The shift is realized by modifying the radii of the border holes adjacent to the PCW core. Some defect holes are introduced to control the beam propagation. The numerical results obtained by the finite-difference time-domain method show that the presented triplexer can separate three specific wavelengths, i.e. 1310, 1490 and 1550 nm with the extinction ratios higher than - 18 dB. The designed device with a size as compact as 12 mu m x 6.5 mu m is feasible for the practical application, and can be utilized in the system of fiber to the home.

Fabrication of triplexers based on flattop SOI AWG

A triplexer is fabricated based on SOI arrayed waveguide gratings (AWGs). Three wavelengths of the triplexer operate at different diffraction orders of an arrayed waveguide grating. The signals of 1490 nm and 1550 nm, which are input from central input waveguide of an AWG, are demultiplexed and the signal of 1310 nm, which is input from central output waveguide of an AWG, is uploaded. The tested results show that the downloaded and uploaded signals have flat-top response. The insertion loss is 9 dB on chip, the nonadjacent crosstalk is less than -30 dB for 1490 nm and 1301 nm, and is less than -25 dB for 1550 nm, the 3 dB bandwidth equates that of the input light source.

Novel triplexing-filter design using silica-based direction coupler and an arrayed waveguide grating

A new triplexing filter based on a silica direction coupler and an arrayed waveguide grating is presented. Using a combination of a direction coupler and an arrayed waveguide grating, a 1310-nm channel is multiplexed and 1490- and 1550-nm channels are demultiplexed for fiber-to-the-home. The direction coupler is used to coarsely separate the 1310-nm channel from the 1490- and 1550-nm channels. Subsequently, an arrayed waveguide grating is used to demultiplex the 1490- from 1550-nm channel. The simulated spectra show the 1-dB bandwidth of 110 nm for the 1310-nm channel and 20 and 20.5 nm for the 1490- and 1550-nm channels. The insertion loss is only 0.15 dB for 1310 nm and 5 dB for 1490 and 1550 nm. The crosstalk between the 1490- and 1550-nm channels was less than -35 dB. (C) 2009 Society of Photo-Optical Instrumentation Engineers. [DOI 10.1117/1.3065508]

Investigation of mode coupling in a microdisk resonator for realizing directional emission

Mode coupling between the whispering-gallery modes (WGMs) is numerically investigated for a two-dimensional microdisk resonator with an output waveguide. The equilateral-polygonal shaped mode patterns can be constructed by mode coupling in the microdisk, and the coupled modes can still keep high quality factors (Q factors). For a microdisk with a diameter of 4.5 mu m and a refractive index of 3.2 connected to a 0.6-mu m-wide output waveguide, the coupled mode at the wavelength of 1490 nm has a Q factor in the order of 10(4), which is ten times larger than those of the uncoupled WGMs, and the output efficiency defined as the ratio of the energy flux confined in the output waveguide to the total radiation energy flux is about 0.65. The mode coupling can be used to realize high efficiency directional-emission microdisk lasers. (C) 2009 Optical Society of America

A DSWN-based specific-purpose neural computing system

The Double Synapse Weighted Neuron (DSWN) is a kind of general-purpose neuron model, which with the ability of configuring Hyper-sausage neuron (HSN). After introducing the design method of hardware DSWN synapse, this paper proposed a DSWN-based specific purpose neural computing device-CASSANN-IIspr. As its application, a rigid body recognition system was developed on CASSANN-IIspr, which achieved better performance than RIBF-SVMs system.

Fabrication of a novel silica PLC hybrid integrated triplexer

A new-style silica planar lightwave circuit (PLC) hybrid integrated triplexer, which can demultiplex 1490-nm download data and 1550-nm download analog signals, as well as transmit 1310-nm upload data, is presented. It combines SiO2 arrayed waveguide gratings (AWGs) with integrated photodetectors (PDs) and a high performance laser diode (LD). The SiO2 AWGs realize the three-wavelength coarse wavelength-division multiplexing (CWDM). The crosstalk is less than 40 dB between the 1490- and 1550-nm channels, and less than 45 dB between 1310- and 1490- or 1550-nm channels. For the static performances of the integrated triplexer, its upload output power is 0.4 mW, and the download output photo-generated current is 76 A. In the small-signal measurement, the upstream 3-dB bandwidth of the triplexer is 4 GHz, while the downstream 3-dB bandwidths of both the analog and digital sections reach 1.9 GHz.

签密方案在分布式协议中的应用

该文基于可验证秘密共享思想和对Zheng的签密方案的必要修改，首次构造了一种不需要可信中心的门限签密方案．它能同时达到门限签名和加密的双重目的，实现代价仅和门限签名相当，并具有非否认性质．该文对当前一些分布式密钥分配协议做了分析，并基于Naor的基本思想，重点利用签密方案设计了协议SC—DKDS．与其它协议相比，该协议在减低实现成本等方面更为有效，因为它不需要认证信道、秘密信道及复杂的零知识证明等．该文还在RO（Random Oracle，随机预言）模型中给出了以上协议的安全性证明．