石墨烯纳米片磁有序和自旋逻辑器件第一原理研究

尺寸效应和拓扑阻挫能够在有限石墨烯纳米片段中形成磁有序,本文对能够产生大自旋或电子自旋反铁磁耦合的石墨烯有限片段进行合理分类,提出几种能够作为基本逻辑门的特殊结构并对其进行第一原理电子结构计算,为设计高密度超快自旋器件提供了有效方案和理论依据.计算结果证明：基于有限石墨烯片段的逻辑门结构能够在室温下进行错误率较低的可纠错运算.     

高频电容器充电电源绝缘栅双极晶体管吸收电路

 高频化是提升电源功率密度的有效方法。为了保护高频电容器充电电源中的开关器件,以串联谐振式电容器充电电源为基础,研究了绝缘栅双极晶体管(IGBT)尖峰电压的产生机理及影响因素。介绍了几种抑制尖峰电压的方法,着重分析了IGBT吸收电路的基本原理,并进行了参数设计。结合仿真软件,对吸收电路的参数进行了优化,将仿真结果和40 kW,50 kHz电容器充电电源样机的实验结果进行对比,验证了提出方案的可行性。     

Mechanism of single-event transient pulse quenching between dummy gate isolated logic nodes

As integrated circuits scale down in size,a single high-energy ion strike often affects multiple adjacent logic nodes.The so-called single-event transient(SET)pulse quenching induced by single-event charge sharing collection has been widely studied.In this paper,SET pulse quenching enhancement is found in dummy gate isolated adjacent logic nodes compared with that isolated by the common shallow trench isolation(STI).The physical mechanism is studied in depth and this isolation technique is explored for SET mitigation in combinational standard cells.Three-dimensional(3D)technology computer-aided design simulation(TCAD)results show that this technique can achieve efficient SET mitigation.     

An Elaborate Supramolecular Assembly for a Smart Nanodevice for Ratiometric Molecular Recognition and Logic Gates

Ingenious approaches to supramolecular assembly for fabricating smart nanodevices is one of the more significant topics in nanomaterials research. Herein, by using surface quaternized cationic carbon dots (CDots) as the assembly and fluorescence platform, anionic sulfonatocalix[4]arene with modifiable lower and upper rims as a connector, as well as in situ coordination of Tb³⁺ ions, we propose an elaborate supramolecular assembly strategy for the facile fabrication of a multifunctional nanodevice. The dynamic equilibrium characteristics of the supramolecular interaction can eventually endow this nanodevice with functions of fluorescent ratiometric molecular recognition and as a nano‐logic gate with two output channels.     

Cross polarization effect of donor–acceptor group on a potential single‐molecule transistor

Theoretical investigation of the polarization effect on a potential single‐molecule transistor has been studied with density functional theory. 4,4′‐(2‐Amino‐5‐nitro‐1,4‐phenylene)bis(ethyne‐2,1‐diyl) dibenzenethiol (AN‐OPE), containing a donor and an acceptor (D–A) crossed to its oligo(p‐phenylene‐ethynylene) (OPE) backbone, was used as a prototype for this study. Simulation results indicate that AN‐OPE has a higher on/off ratio on conductance than OPE because of the larger polarization along the D–A direction. This high on/off ratio was proved by the 20 times variation in molecular charge, 15 times variation in bond lengths, 49 times variation in polarizability, 9 times variation in the rotation angles, and 13 times variation in the highest occupied molecular orbital–lowest unoccupied molecular orbital gaps under the same gate using B3LYP/6‐31G (d, p). And results imply that conjugated molecules with a cross D–A structure could be a good direction for constructing a better single‐molecule field‐effect transistor. Copyright © 2014 John Wiley & Sons, Ltd.     

Anion Sensors as Logic Gates: A Close Encounter?

Computers have become smarter, smaller, and more efficient due to the downscaling of silicon‐based components. Top‐down miniaturisation of silicon‐based computer components is fast reaching its limitations because of physical constraints and economical non‐feasibility. Therefore, the possibility of a bottom‐up approach that uses molecules to build nano‐sized devices has been initiated. As a result, molecular logic gates based on chemical inputs and measurable optical outputs have captured significant attention very recently. In addition, it would be interesting if such molecular logic gates could be developed by making use of ion sensors, which can give significantly sensitive output information. This review provides a brief introduction to anion receptors, molecular logic gates, a comprehensive review on describing recent advances and progress on development of ion receptors for molecular logic gates, and a brief idea about the application of molecular logic gates.     

Functional monadic Heyting algebras

We show every monadic Heyting algebra is isomorphic to a functional monadic Heyting algebra. This solves a 1957 problem of Monteiro and Varsavsky [9]. Received May 18, 2001; accepted in final form October 18, 2001.     

模糊Hopfield网络及其模糊聚类功能研究

本文提出了一种能进行模糊逻辑计算的Ｈｏｐｆｉｌｅｄ型人工神经元网络，ＦｕｚｚｙＨＮ的神经元对应模式集合中的元素，模式间的模糊相似关系作为联结神经元的权值矩阵被存储在ＦｕｚｚｙＨＮ中。本文对ＦｕｚｚｙＨＮ的稳定性及模糊聚类功能进行研究，获得了良好的理论分析结果和实验研究结果。     

One-operation image algebra for optical processing

A binary image algebra with one operation of a logic operation followed by a dilation and its modification with three additional operations for threshold processing of grey level images are developed in this paper. All the binary image processing functions and various grey level image processing functions related to morphological operations can be represented by the algebraic structure. The algebra is particularly suitable for parallel processing by optics in a cellular logic image processor architecture.