bluuebunny/crossref_metadata_2025_split huggingface dataset:
Review of Polymer Physics 1992
Authors: Ewen Bernd 
Published: May 2005

Advances in polymer physics are discussed, including the latest insights into the morphology of polymeric systems, small‐angle X‐ray studies of liquid‐crystalline polymers, and the influence of chain branching on the thermodynamic and hydrodynamic properties of polymer solutions and melts. Among the newly developed or adapted methods, NMR imaging can be used to calculate the stress distribution in a test strip of polymer, as shown in the Figure. magnified image
Optical second‐harmonic effect of sol–gel inorganic–organic nanocomposites
Authors: Kador Lothar , Fischer Reiner , Haarer Dietrich , Kasemann Reiner , Brück Stefan , Schmidt Helmut , Dürr Heinz 
Published: May 2005

Second‐order nonlinear optically (NLO) active materials have promising technical applications in optoelectronic devices. A general problem in NLO‐active polymeric systems is the decay of orientational order with time. Results are presented which show that using inorganic–organic composite materials produced by the sol–gel process as a rigid matrix for oriented χ(2) chromophores (Figure) may provide a means of overcoming this problem. magnified image
Electroluminescent devices based on poly(methylphenylsilane)
Authors: Suzuki Hiroyuki , Meyer Harald , Simmerer Jürgen , Yang Jiping , Haarer Dietrich 
Published: May 2005

The fabrication of high‐efficiency light‐emitting diodes (LEDs) based on sublimed molecular films has attracted much attention in the search for materials for application in large‐area flat‐panel displays. Here, multilayered LEDs based on poly(methylphenylsilane), PMPS, as the hole transporting material are reported (see Figure). In contrast to polyphenylenevinylene, PMPS films exhibit a high effective mobility of holes, making the material suitable for fast switching applications. magnified image
Nonplanar tetrathiafulvalene vinylogues
Authors: Kato Hiroshi , Kobayashi Tomoshige 
Published: May 2005

Planarity of the components of conducting charge‐transfer (CT) complexes has been thought to be necessary in order to maximize overlap. Recently, a number of distorted, nonplanar tetrathiafulvalene (TTF) analogues (e.g. see Figure) have been prepared and found to be viable compounds for the formation of CT complexes. Recent progress is discussed. magnified image
Electronic origin of scanning tunneling microscopy images and carbon skeleton orientations of normal alkanes adsorbed on graphite
Authors: Liang Weigen , Whangbo Myung‐Hwan , Wawkuschewski Aleksander , Cantow Hans‐Joachim , Magonov Sergei N. 
Published: May 2005

STM images of organic insulating molecules adsorbed on conducting substrates can only be understood if their electronic origin is known. Images of normal alkanes on graphite (n‐C36H74) is shown in the Figure are interpreted here on the basis of their partial electron density plots ρ(r0,ef), demonstrating that the linear alkanes can “tumble” and change their orientation with respect to the graphite surface. magnified image
The deformability of the thiophene ring: A key to the understanding of the conformational properties of oligo‐ and polythiophenes
Authors: Barbarella Giovanna , Zambianchi Massimo , Bongini Alessandro , Antolini Luciano 
Published: May 2005

Oligothiophenes in solution and in the solid state have different conformational properties, as can be concluded from the spectroscopic and theoretical data and X‐ray structure of three di‐ and tetramethyl α‐conjugated quaterthiophenes (see Figure) reported here. magnified image
Molecular recognition of alkali‐ions by crown‐ether‐functionalized poly(alkylthiophenes)
Authors: Bäuerle Peter , Scheib Stefan 
Published: May 2005

New crown‐ether‐functionalized alkyl(oligothiophene)s (see Figure) have been synthesized and electropolymerized to alkali metal ion sensitive poly(alkylthiophene)s. It is shown for the first time that the redox chemistry of a conducting polymer is strongly influenced by the specific host‐guest interaction, although the crown ether units are not π‐conjugated to the conducting backbone but separated by an insulating oxa‐alkyl chain. magnified image
Fullerene polymers
Authors: Hirsch Andreas 
Published: May 2005

Polymeric fullerene materials come in tree main types: “pendant”, where C60 is attached to the side chain of a polymer (see Figure) or to the surface of a solid, “dendritic”, and “in‐chain”, where the fullerene forms part of the main chain. The synthesis of the various types is discussed and their expected unique properties described. magnified image
Sensor materials for solvent vapor detection—donor–acceptor and host–guest interactions
Authors: Dickert Franz L. , Haunschild Alexander 
Published: May 2005

Sensors for a huge variety of detection tasks can be made by combining chemically sensitive materials with microstructured physical devices. How individual analyte species can be recognized using host–guest binding schemes (the Figure shows a paracyclophane host molecule) and how categories of compounds can be identified using sensors that respond to different functionalities are reviewed. magnified image
Phenyl groups as molecular fasteners: Phenyltelluro‐substituted tetrathiafulvalenes
Authors: Khodorkovsky Vladimir Y. , Wang Changsheng , Becker James Y. , Ellern Arkady , Shapiro Lev , Bernstein Joel 
Published: May 2005

Phenyltelluro–tetrathiafulvalene (TTF) derivatives, for example those shown in the Figure, are reported to exhibit one‐component two‐dimensional networks of shortened molecular interactions and electrical conductivities that are unsually high for neutral organic molecules. Evidence for stacking of TTF groups—despite the bulky phenyl groups—is presented. magnified image
Immobilization of functionalized lipids in a random poly(methacrylate) copolymer monolayer
Authors: Lowack Klaus , Helm Christiane A. 
Published: May 2005

Model membranes, based on thin organic films containing an even, random distribution of functionalized amphiphilic lipid molecules, are reported. The monolayers are stabilized by polymerization and can be transferred to solid substrates using he Langmuir–lodgett technique, allowing structures such as that shown in the Figure to be produced. magnified image
Layered ceramics
Authors: Moya José S. 
Published: May 2005

Layered ceramic‐ceramic composites exhibit improved mechancial performance over monolithic composites, design flexibility for the solution of complex technological problems such as with functionally gradient materials (e.g. Al2O3/Y‐TZP, see Figure), and provide a model for the sudy of interfacial reactions between two incompatible particulate systems. magnified image
Polymeric drug delivery systems
Authors: Román Julio San , Gallardo Alberto , Levenfeld Belén 
Published: May 2005

Controlled drug release‐ and targeted drug delivery systems based on polymers are reviewed. The design of polymer‐drug systems, for example the one shown in the Figure, which contains a solubilizer, the drug linked to the backbone through a spacer, and a targeting moiety for guiding the drug to the desired site, and the factors which influence their effectiveness are discussed. magnified image
Substituted Rigid Rod‐Like Polymers—Building Blocks for Photonic Devices**
Authors: Neher Dieter 
Published: May 2005

Substituted rigid rod‐like polymers (RRPs) can be exploited to control the microscopic order in, and the fabrication of, devices with potential uses in photonics. The supermolecular structures formed by these interesting materials (e.g. see Figure) are considered, attention being focused on the correlation between structural properties and macroscopic properties such as nonlinear susceptibilities magnified image.
Synthesis of novel polymers containing cyclobutadiene thiophene and alkyne units: polymeric organometallic mesogens**
Authors: Altmann Markus , Enkelmann Volker , Lieser Günther , Bunz Uwe H. F. 
Published: May 2005

A new class of organometallic liquid‐crystalline rigid‐rod polymers containing thiophene (see Figure) are reported and it is shown how their phase behavior can be tuned through variation of the side groups. The crystallization of the compound shown in the Figure proceeds through a transient lyotropic smectic state, a state hitherto unknown in polymeric organometallic systems magnified image.
Noble metal loaded block lonomers: micelle organization, adsorption of free chains and formation of thin films**
Authors: Spatz Joachim P. , Roescher Arno , Sheiko Sergei , Krausch Georg , Möller Martin 
Published: May 2005

Monitoring the formation of ultrathin films by scanning force microscopy provides information, for example, on the concentration dependence of the film structure (the Figure shows micelle agglomeration from high concentration solutions to form a layer with holes) and insight into the process from micelle formation to structural transformation in the films magnified image.
Change in the shape of copper nanoparticles in ordered phases
Authors: Tanori Judith , Paule Pileni Marie 
Published: May 2005

The shape of copper metal particles (see Figure) is demonstrated to depend on the structure of the mesophase (cylindrical reverse micelles, interconnected networks of surface aggregates or lamellar phases) i the surfactant system used as a microreactor for their synthesis. An understanding of this correlation is of great importance for magnetic recording technology magnified image.
The preparation of novel silica gel hollow tubes**
Authors: Nakamura Hidenori , Matsui Yasushi 
Published: May 2005

Work‐like silica gel hollow tubes have been prepared using a sol‐gel method. The tubes (see Figure), wich are porous, mostly have one end closed, although occasionally tubes with both ends closed are produced. The preparation method, which involves the hdyrolysis of tetraethylorothosilicate in a mixture of ethanol, ammonia, water and citric acid monohydrate, is described magnified image.
Ultraviolet electroluminescence from an organic light emitting diode
Authors: Berggren Magnus , Granströim Magnus , Inganas Olle , Andersson Mats 
Published: May 2005

The extension of the emission region or organic LEDs into the ultraviolet region is reported. Emission at 394 nm is achieved by modifying the geometry of a device based on poly(octylphenyl)bithiophene (PTOPT) and poly(octylphenyl)oxadiazole (PBD) which had previously been shown to emit white light. Through changing the geometry the red and green emission peaks have been suppressed and the UV band (from the PBD) enhanced magnified image.
Doped and heteroatom‐containing fullerene‐like structures and nanotubes
Authors: Tenne Reshef 
Published: May 2005

AbstractA review of the current knowledge on carbon fullerenes doped with foreign atoms and heteroatom‐containing fullerene‐like structures and nanotubes is provided. Strong covalent bonds lend high specificity and stabilize the hollow‐cage and symmetric structure of these moieties. These structures are distinct from noble‐gas and metallic clusters, where either weak van der Waals forces or stronger metallic bonds, which are not very specific, hold the cluster atoms together. In the latter kind of clusters, atoms gain stability through close packing and large coordination numbers and consequently they cannot afford a hollow core. Nonetheless some intermetallic nanoparticles exhibit truncated icosahedral symmetry. The field is divided, somewhat artificially, into two separate categories. One family consists of fullerene‐like clusters assembled from different atoms which do not have a bulk counterpart of similar chemical formula. The other group is that of fullerene‐like nanostructures which are obtained mainly from ubiquitous 2‐D layered compounds; various elements and compounds with 3‐D character and also from certain metallic alloys. It is shown that nanoparticles of 2‐D compounds are unstable in the planar form and they reconstruct into hollow‐cage nanoparticles, spontaneously. Nanosolids of this kind may reveal vastly different properties from their bulk predecessors. Numerous applications for the doped and heteroatom fullerene‐like materials in the fields of catalysis, lubrication, electronic and photonic devices, alternative energy sources, etc. are expected upon further study and development.
Chromophore‐zeotype composites: Direct synthesis of an array of strictly aligned metal‐organic complex chromophores in a crystalline silica matrix
Authors: Behrens Peter , van de Goor Gianpietro , Marlow Frank , Hoffmann Katrin , Kallus Stefan , Schüth Ferdi 
Published: May 2005

Chromophores embedded in zeolite‐type hosts have potential applications in optical devices. However, the conventional preparation results in an inhomogeneous distribution of the chromophores. It is demonstrated that direct synthesis can result in chromophore‐zeolite composites with well‐defined stoichiometry and uniform chromophore distribution, as illustrated for [CocpF⊕]‐NON in the figure. magnified image
Organic two‐dimensional templates for the fabrication of inorganic nanostructures: Organic/inorganic superlattices
Authors: Kimizuka Nobuo , Kunitake Toyoki 
Published: May 2005

The self‐organization of inorganic precursors in predetermined patterns is the first step towards the ability to synthesize mesoscopic inorganic materials. Several techniques are described, including the immobilization of inorganic precursors by coordination with bilayer ligands (see figure), which led, for example, to a novel Cd4Br12S cluster. Finally, the formation of organic/inorganic superlattices is outlined. magnified image
Alignment of single‐crystal zeolites by means of microstructured surfaces
Authors: Scandella Loris , Binder Gunnar , Gobrecht Jens , Jansen Jacobus C. 
Published: May 2005

Nanoscale devices based on zeolites require either thin films of single‐crystalline zeolites or ordered arrangements of zeolite crystals. A novel technique—with potentially wide applications—is reported here that enables thousands of zeolite crystals to be ordered using a microstructured silicon surface. The figure shows zeolites oriented in two positions (marked A and B) in silicon grooves. magnified image
Continuous yttria‐stabilized zirconia fibers
Authors: Clauss Bernd , Grüb Andrea , Oppermann Wilhelm 
Published: May 2005

Polycrystalline oxide fibers have not yet been exploited to their full potential, perhaps because of difficulties with processability. In the successful new route for the production of continuous yttria‐stabilized zirconia fibers detailed here, ZrO2 particles sols are used as oxide‐forming components. The fine‐grained compact ceramic fibers of tetragonal zirconia polycrystals obtained 2 mol‐% Y2O3 are shown in the figure. magnified image
A single source approach to the synthesis of CdSe nanocrystallites
Authors: Trindade Tito , O'Brien Paul 
Published: May 2005

Synthetic routes to semiconductor nanocrystallites have become of particular interest since nanoparticle devices have been constructed. The route reported here for CdSe uses a single source in tri‐n‐octylphosphine oxide instead of the hazardous metal alkyls conventionally employed. The characterization of the nanocrystallites (see figure) shows that they are crystalline, approximately spherical, and close to monodispersed. magnified image
Structure‐property relationships in nonlinear optical tetraethynylethenes
Authors: Bosshard Christian , Spreiter Rolf , Günter Peter , Trkwinski Rik R. , Schreiber Martin , Diederich François 
Published: May 2005

The third‐order nonlinear optical properties of donor‐acceptor substituted tetraethynylethenes (see figure and also the preceding contribution) are presented with special emphasis on the structure‐property relationships and the effect of conjugation paths on the optical nonlinearity. In one single class of materials the influence of donor‐acceptor substitution as well as of full two‐dimensional conjugation on the third‐order nonlinearity is clearly shown. magnified image
Electroluminescent diodes from a single component emitting layer of dendritic macromolecules
Authors: Wang Pei‐Wei , Liu Yu‐Ju , Devadoss Chelladurai , Bharathi P. , Moore Jeffrey S. 
Published: May 2005

Organic LEDs based on dendrimer materials are reported (see the figure for an example; a dot represents phenylene). Single‐organic‐layer devices have been produced using structurally welldefined dendritic modules. Although the efficiency of the devices is still low, this work provides a basis for a systematic strategy for tuning the properties of the active layers of organic LEDs. magnified image
Two‐ and three‐dimensional crystallization of polymeric microspheres by micromolding in capillaries
Authors: Kim Enoch , Xia Younan , Whitesides George M. 
Published: May 2005

Micromolding in capillaries (MIMIC) is a novel, simple and convenient procedure for crystallizing microspheres from latex suspensions onto a support, and for delivering microspheres to and assembling them in geometrically confined regions on the surface of substrate (see figure). The principle of the method is outlined, examples are given, and possibilities for applications—e.g., in optical devices and microelectronics—are sketched. magnified image
Biodegradable Polymeric Materials
Authors: Chiellini Emo , Solaro Roberto 
Published: May 2005

What can stop the mountain of discarded plastic packaging from growing? One solution to be considered is the development and use of biodegradable polymers. The advantages and drawbacks of various biodegradable plastics, water‐soluble polymers, and natural and semisynthetic polymers are outlined in tis review. The Figure shows a fork made of ECO‐PLA, which is based on poly(lactic acid), after 33 days of degradation. magnified image
Angle‐Scanned Photoelectron Diffraction: Probing crystalline ultrathin films
Authors: Granozzi Gaetano , Sambi Mauro 
Published: May 2005

AbstractElectrons emitted from the core levels of a photon‐irradiated crystalline sample undergo scattering by atoms in the vicinity of the emitting species. Subsequent interference phenomena between the electron wave portions propagating to the detector produce intensity modulations as a function of the direction of detection. This process constitutes the physical basis of the angle‐scanned X‐ray photoelectron diffraction (XPD) technique. The resulting modulations, properly interpreted, are rich in structural information concerning the near‐surface atomic layers. In this review, after an introduction to the principles of XPD, some selected results in the field of ultrathin epitaxial films will be reported in order to outline the merits of the technique. Qualitative structural information (e. g., growth modes and lattice distortions) is directly obtained from the experimental raw data without the need for theoretical simulation. On the other hand, quantitative structural parameters, as well as the presence of stacking faults and other structural defects, may be deduced by using a trial‐and‐error fitting procedure based on simple scattering models.
Functionalization of sexithiophene with electron‐donating methylsulphanyl groups
Authors: Barbarella Giovanna , Zambianchi Massimo , Di Toro Rossanna , Colonna Martino , Antolini Luciano , Bongini Alessandro 
Published: May 2005

Novel soluble sexithiophenes (6Ts) β‐functionalized with electron‐donating methylsulphanyl groups are reported. The resulting processable sexithiophenes, two examples of which are shown in the Figure, have optical gaps that can be finely tuned around the value for unsubstituted α‐6T. The observed liquid‐crystal behavior described here indicates a high degree of molecular organization in the solid in at least one case. magnified image
NLO responses of organic materials: The vibrational approach
Authors: Zerbi Giuseppe , Del Zoppo Mirella , Castiglioni Chiara , Zuliani Paola 
Published: May 2005

How the hyperpolarizabilities of organic polyconjugated materials can be obtained using vibrational spectroscopy is described. This recent work by a group in Milan opens up a completely new field of vibrational spectroscopy relevant o photonics. Results for the molecule shown in the Figure (among others) are presented as an illustration of the reliability of this method. magnified image
Cascading of Second‐Order Nonlinearities in Polar Materials
Authors: Bosshard Christian 
Published: May 2005

The combination of two second‐order nonlinear optical (NLO) processes, termed cascading, can induce third‐order nonlinearities, which are of major interest for all‐optical signal processing. The concept of cascading and the basic ideas behind it are explained and some of the molecules of greatest potential in this area (e.g., DANPH, see Figure) introduced. Methods for determining cascaded nonlinearities, effects based on cascaded processes, and materials considerations are also reviewed. magnified image
A mesogen‐functionized carbosilane dendrimer: A dendritic liquid crystalline polymer
Authors: Lorenz Klaus , Hölter Dirk , Stühn Bernd , Mülhaupt Rolf , Frey Holger 
Published: May 2005

The first dendritic liquid crystalline polymer (DLCP), consisting of a flexible, second‐generation dendritic carbosilane scaffold substituted with 36 rid cyanobiphenyl groups (see Figure), has been prepared. The synthesis and characterization of the mesophase are reported as an initial approach to determining how the formation of liquid crystal phases is related to the mesogen density and the spacer length in DLCPs. magnified image
Nanoparticular intermetallics and alloys via inorganic grignard reagents
Authors: Aleandri Lorraine E. , Bogdanović Borislav , Dürr Christine , Jones Deborah J. , Rozière Jacques , Wilczok Ursula 
Published: May 2005

Novel inorganic Grinard complexes (e.g., that in the Figure) used as reagents enable nanoparticulate bimetallic systems, i.e., intermetallics or alloys, to be prepared in a controlled two‐stage process. The preparation and characterization of inorganic Grignard reagents and, in particular, the synthesis of nanoparticulate intermetallics and alloys via such reagents are briefly reviewed. magnified image
Novel PPV derivatives emitting light over a broad wavelength range
Authors: Jin Jung ‐H , Chung Sung‐Jae , Kim Kong‐Kyum 
Published: May 2005

Organic films for display applications have usually been developed with the aim of individual emission of red, blue, and green light. Another approach, presented here, is to design organic light‐emitting devices that emit over a broad spectral range, i.e., essentially white light. The preparation of two new polymer (see Figure) films is described, together with the results of absorption, photoluminescence, and electroluminescence measurements. magnified image
Novel κ‐type organic metal based on a bis‐fused tetrathiafulvalene derivative
Authors: Misaki Yohji , Miura Takeshi , Taniguchi Masateru , Fujiwara Hideki , Yamabe Tokio , Mori Takehiko , Mori Hatsumi , Tanaka Shoji 
Published: May 2005

A novel k‐type organic metal based on 4,5,‐cyclohexeno‐TTP (where TTP is bis‐fused tetrathiafulvalene, TTF), see Figure, is reported. The synthesis, structure, and electrical properties are described. It is suggested that, following this demonstration of a TTF‐based organic metal without a chalcogeno‐based substituent, further CH‐TTP salts should be investigated for conductivity and superconductivity.magnified image
Rapid microbiology: Applications of bioluminescence in the food industry a review
Authors: Stannard C. J. , Gibbs P. A. 
Published: May 2005

AbstractThe bioluminescent assay of ATP is rapid and simple and may be used as an estimate of microbial numbers. It therefore shows great potential as a technique to provied information on the microbiological quality of a food within a few minutes, in comparison with conventional techniques, which provide results retrospectively. Howver, despite the advantages of speed and senstitivity, no food microbiologists are using the technique for routine quality control and hygiene monitoring. This review seeks to highlight the reasons for this, and to offer some ideas for future research to increase the acceptance of ATP assays within the food industry.