Synthesis of artificial neural networks by transconductors only

Hardware implementation of artificial neural networks has been attracting great attention recently. In this work, the analog VLSI implementation of artificial neural networks by using only transconductors is presented. The signal flow graph approach is used in synthesis. The neural flow graph is defined. Synthesis of various neural network configurations by means of neural flow graph is described. The approach presented in this work is technology independent. This approach can be applied to new neural network topologies to be proposed or used with transconductors designed in future technologies.     

水下成像的现状和发展动向

本文以下水成像在军事，海洋开发工程应用为基础，论述了水下观测和成像中采用微光电视摄像机和激光器件及其系统的技术现状和发展动向。     

锁相电子散斑系统

电子散斑干涉计量在变形量检测¹、无损探伤、振动分析^(2,3)等领域具有广泛的应用前景,目前它之所以未能实用化,最重要的原因就是该系统对环境的要求过高,特别是物体的振动和空气的扰动对测量结果影响很大,甚至会导致测量失败,因而国内外学者在不断寻找解决此问题的锁相技术。本文提出了一种简易的切实可行的锁相方法-光学锁相法,消除了物体的振动和空气扰动对电子散斑测量的影响。     

铁(Ⅲ)-邻菲罗啉溶液体系的光化学还原 Ⅱ.气相色谱法研究光化反应机理

关于Fe(Ⅲ)-邻菲罗啉(phen)溶液的光化学还原现象的记载可追溯到十九世纪末。     

有机/无机异质结薄膜发光二极管

聚合物发光二极管（LED）自从Burrou吵es等于1990年首次报导PPV的电致发光［‘］以来，由于聚合物半导体具有热和化学性能的稳定，克眼了有机小分子材料容易晶化的优点，在平板显示领域必将占有一席之地，从而吸引了许多科学家投身到这一领域来．众所周知，要想实现LED的实用化     

A Two-dimensional Lanthanide Coordination Framework with a New Amide-type Tripodal Ligand, 2,2′,2＂-Nitrilotris{[（2′- benzylaminoformyl）phenoxy]ethyl}amine

The La(III) complex with a new amide‐type tripodal ligand,2,2′.2″‐nitrilotris{[(2′‐benzylaminofomyl)‐phenoxylethyl)amine (L), was synthesized and characterized by X‐ray crystallographic analysis. Crystal data: C₄₈H_55.50LaN₇O_18.75, M_r=1169.40, monoclinic. space group, P2₁/n, a= 1.0644(3) nm. b=2.3889(5) nm, c= 2.1917(5) nm, β=90.65°, V=5.573(2) nm³, Z=1, D_c=1.394 g°cm^?3, R₁=0.0487, wR [1>2s?(I)]=0.1266. The results reveal that each La(III) ion binds to 9 oxygen atoms, three of which belong to carbonyl groups from three tripodal ligands and six to three bidentate nitrate groups and a two‐dimensional sheet of 4.8² networks is assembled by metal‐ligand coordination interaction. L, a heptadentate compound, merely acts as a tridentate bridging spacer due to its steric hindrance and links the La(III) ions as three‐connected nodes.     

Use of Two-Dimensional Liquid Chromatography Combined with Diode-Array and Mass Spectrometric Detection for Analysis of Compounds in Flos Lonicera

Comprehensive two-dimensional liquid chromatographic separation by means of a combination of ion-exchange chromatography (IEC) and reversed-phase liquid chromatography (RPLC) has been realized and applied to the analysis of components of a traditional Chinese medicine Flos Lonicera. In the first dimension the components of a Flos Lonicera extract is separated on strong anion-exchange (SAX) column according to the charge-exchange properties of the components. In the second dimension the components are further fractionated by reversed-phase liquid chromatography (on ODS) on the basis of their hydrophobicity. The RPLC effluent is desalted and split and the components are identified on-line by use of both diode-array detection and mass spectrometry with atmospheric pressure chemical ionization (APCI–MS). In this way, the extract of Flos Lonicera can be rapidly separated, desalted, and analyzed, with determination of molecular weight. More than 58 components of an extract of Flos Lonicera were well resolved and six were tentatively identified from their UV and mass spectra.     

Studies on synthesis and infrared and fluorescence spectra of new europium and terbium complexes with an amide-based open-chain crown ether

An amide-based open-chain crown ether ligand and its complexes with europium and terbium were synthesized. The complexes were characterized by elemental analysis, infrared spectra and conductivity. The europium and terbium ions were found to coordinate to the C=O oxygen atoms and pyridine nitrogen atoms. The fluorescence properties of these complexes in DMF and CH3OH/CHCl3 were studied. Under the excitation of UV light, these complexes exhibit characteristic fluorescence of europium and terbium ions. The solvent factors influencing the fluorescent intensity are discussed.     

吡啶—2,6—二羧酸体系导数荧光法同时测定铀,钐,铕,铽,镝

本研究了吡啶－２，６－二羧酸（ＤＰＡ）体系导数荧光法同时测定铀，钐，铕，铽，镝的最佳条件。在ｐＨ５．５，４．８×１０＾－＾５ｍｏｌ／ＬＤＰＡ，激发波长２７２ｎｍ的条件下，可分别在５１８，６３９，６２１，５３９和６６ｎｍ处测定铀，钐，铕，铽和镝，检测限分别达到７，０．４，０．００４，０．０２６和０．２５ｎｇ／ｍＬ。应用本法测定了混合成试液中上术五种离子含量，回收率为９２．３－１０８．１％。