摘要:

We investigated the EL characteristics of a series of dialkyl substituted polysilanes to clarify the fundamental electroluminescent (EL) properties of [sgrave]-conjugated one dimensional Si polymers. The EL properties of these polysilanes were found to be strongly influenced by branch-like defects in the Si backbone from EL spectrum measurements and the energetics of carrier injection into the polysilanes. We also demonstrated the influence of a change in conformation on the EL spectrum of dialkyl polysilane-based light emitting diodes.

ISSN:1058-725X    

DOI:10.1080/10587259808044333

出版商:Taylor & Francis Group    

年代:1998

数据来源: Taylor

摘要:

We constructed high-quality monolayer Langmuir-Blodgett (LB) films using a novel molecule C37H50N4O4synthesized by us. This molecule is the long-chain alkyl derivative which has dinitrobenzene moiety (acceptor unit) and dihydrophenazine one (donor unit) bridged by methylene group with constant distance and bond angle to behave as unimolecular photoelectric device with the control of the potential between donor and acceptor subunits. We transferred the monolayer film onto a mica plate and succeeded in getting molecular images by atomic force micoscopy.

ISSN:1058-725X    

DOI:10.1080/10587259808044334

出版商:Taylor & Francis Group    

年代:1998

数据来源: Taylor

摘要:

A new type of concentration dependence,i.e., intersite-distance (ρ) dependence, of the activation energy for the hole drift mobility of the 9-ethylcarbazole-3-carbaldehyde diphenylhydrazone (ECH) and 9-ethylcarbazole-3-carbaldehyde methylphenylhydrazone (ECMH) dispersed in polycarbonate (PC) is reported. The activation energy for charge transport in the ECH or ECMH-doped PC systems gradually decreases with decreasing ρ for large values of ρ, becoming nearly constant for small values of ρ. This behavior contrasts with that for the 4-diphenylaminobenzaldehyde diphenylhydrazone (DPH)-doped PC system. Specific intermolecular interactions between ECH or ECMH molecules having a planar carbazole moiety at relatively high concentrations are suggested to be responsible for this concentration dependence of the activation energy.

ISSN:1058-725X    

DOI:10.1080/10587259808044335

出版商:Taylor & Francis Group    

年代:1998

数据来源: Taylor

摘要:

Stereophotolithography (SPL) allows to manufacture 3D polymer parts directly from Computer Aided Design data files. Its principle is the space resolved polymerization of a resin by a laser. We first discuss the possibilities to make parts with a very high resolution. A first approach was to push the classical SPL process to its limits to get a resolution of about 30 micrometres. A second really innovating one was to modulate the light flux by a liquid crystal display and we obtained a resolution of 5 micrometres. Since the use of these parts is limited by the nature of photopolymers, we also developed a new process to make complex polymer/metal parts directly. It consists in making the part layer by layer by using three techniques: SPL, electrodeposit of copper and laser silver plating.

ISSN:1058-725X    

DOI:10.1080/10587259808044336

出版商:Taylor & Francis Group    

年代:1998

数据来源: Taylor

摘要:

A practical model of a quantum logic gate is proposed, which consists of two photo-induced, charge-separating molecular systems. Basic concept of quantum computing and recent studies in ultrafast photophysical processes in highly organized molecular assemblies are reviewed.

ISSN:1058-725X    

DOI:10.1080/10587259808044337

出版商:Taylor & Francis Group    

年代:1998

数据来源: Taylor

摘要:

Recent progress of the graded-index polymer optical fiber (GI POP) is reviewed. The low-loss perfluorinated (PF) polymer base GI POF experimentally achieved gigabit transmission for more than 200 m in the range of visible to near infrared region. In addition, improvement of the thermal and long-term stability of the bandwidth of the GI POF with using a new dopant material is described.

ISSN:1058-725X    

DOI:10.1080/10587259808044338

出版商:Taylor & Francis Group    

年代:1998

数据来源: Taylor

摘要:

Unconventional optical responses have been revealed for the perovskite manganese oxide, Pr1-xCaxMnO3, which is known to undergo the insulatormetal (I-M) transition relevant to the magnetic field induced melting of the charge-ordered (CO) state. Optical conductivity spectrum is drastically modified over 0–1 eV from a gap-like feature into a metallic band with application of magnetic field of 7 T. It was found that such an I-M transition can be caused by photo-excitation as well. The electrical conductivity and magnetization increase abruptly with irradiation of visible/IR laser, indicating the photo-melting of the CO state and the photo-generation of ferromagnetic metallic domains.

ISSN:1058-725X    

DOI:10.1080/10587259808044339

出版商:Taylor & Francis Group    

年代:1998

数据来源: Taylor

摘要:

Transient properties of mechanoluminescence (ML) from europium complex in powder and in polymer-dispersed film were investigated. In polymer-dispersed film, its decay curve was found to be composed of two components corresponding to the emission from ambient nitrogen molecules and europium ion. On the other hand, the decay curve of powder was composed of a single component corresponding to the emission from europium ion. From these results and supplemental experiments, the difference in ML excitation mechanism between polymer-dispersed film and powder is discussed.

ISSN:1058-725X    

DOI:10.1080/10587259808044340

出版商:Taylor & Francis Group    

年代:1998

数据来源: Taylor

摘要:

This is a scanned image of the original Editorial Board page(s) for this issue.

ISSN:1058-725X    

DOI:10.1080/10587259808044302

出版商:Taylor & Francis Group    

年代:1998

数据来源: Taylor