bluuebunny/crossref_metadata_2025 huggingface dataset:
Naming very familiar people: When retrieving names is faster than retrieving semantic biographical information
Authors: Brédart Serge , Brennen Tim , Delchambre Marie , McNeill Allan , Burton A. Mike
Published: May 2005

One of the most reliable findings in the literature on person indentification is that semantic categorization of a face occurs more quickly than naming a face. Here we present two experiments in which participants are shown the faces of their colleagues, i.e., personally familiar people, encountered with high frequency. In each experiment, naming was faster than making a semantic classification, despite the fact that the semantic classifications were highly salient to the participants (Experiment 1: highest degree obtained; Experiment 2: nationality). The finding is consistent with models that allow or parallel access from faces to semantic information and to names, and demonstrates the need for the frequency of exposure to names to be taken into account in models of proper name processing e.g. Burke, Mackay, Worthley and Wade (1991).
Childhood IQ and all‐cause mortality before and after age 65: Prospective observational study linking the Scottish Mental Survey 1932 and the Midspan studies
Authors: Hart C. L. , Taylor M. D. , Smith G. , Whalley L. J. Davey , Starr J. M. , Hole D. J. , Wilson V. , Deary I. J.
Published: May 2005

Objectives.The objective was to investigate how childhood IQ related to all‐cause mortality before and after age 65.

Design.The Midspan prospective cohort studies, followed‐up for mortality for 25 years, were linked to individuals' childhood IQ from the Scottish Mental Survey 1932.

Methods.The Midspan studies collected data on risk factors for cardiorespiratory disease from a questionnaire and at a screening examination, and were conducted on adults in Scotland in the 1970s. An age 11 IQ from the Scottish Mental Survey 1932, a cognitive ability test conducted on 1921‐born children attending schools in Scotland, was found for 938 Midspan participants. The relationship between childhood IQ and mortality risk, adjusting for adulthood socio‐economic confounders, was analysed. The effect of adjustment for childhood IQ on the relationship between established risk factors (blood pressure, smoking, height and respiratory function) and mortality was also investigated.

Results.For deaths occurring up to age 65, there was a 36% increased risk per standard deviation decrease (15 points) in childhood IQ which was reduced to 29% after adjusting for social class and deprivation category. There was no statistically significant relationship between childhood IQ and deaths occurring after the age of 65. Adjustment for childhood IQ attenuated the risk factor—mortality relationship in deaths occurring up to age 65, but had no effect in deaths occurring after age 65.

Conclusions.Childhood IQ was significantly related to deaths occurring up to age 65, but not to deaths occurring after age 65.
Substance use among pregnant women in the context of previous reproductive loss and desire for current pregnancy
Authors: Coleman Priscilla K. , Reardon David C. , Cougle Jesse R.
Published: May 2005

Objective. The primary objectives of this study were to explore maternal history of perinatal loss and pregnancy wantedness as correlates of substance use during pregnancy.

Method. The research design involved interviewing women who gave birth in Washington DC hospitals during 1992. Interview data included pregnancy history (prior births, induced abortions, miscarriages, and stillbirths), desire for the pregnancy (wanted, not wanted, mistimed), socio‐demographic information, timing of onset of prenatal care, and substance use (cigarettes, alcohol, and drugs) during pregnancy.

Results. A history of induced abortion was associated with elevated risk for maternal substance use of various forms; whereas other forms of perinatal loss (miscarriage and stillbirth) were not related to substance use. Unwanted pregnancy was associated with cigarette smoking during pregnancy, but not with any other forms of substance use.

Conclusions. Reproductive history information may offer insight to professionals pertaining to the likelihood of women using substances in a later pregnancy.
Causal beliefs and behaviour change post‐myocardial infarction: How are they related?
Authors: French David P. , James Delyth , Horne Rob , Weinman John
Published: May 2005

Introduction.Weinman, Petrie, Sharpe, and Walker (2000)showed that the causal attributions of a sample of first‐time myocardial infarction (MI) patients and their spouses from Auckland, New Zealand, were associated with changes in health‐related behaviour over the first 6 months post‐MI. However, their analyses did not control for pre‐MI health‐related behaviour.

Method.This paper reports a re‐analyses of the Auckland data, and a replication study conducted with 155 first‐time MI patients in Brighton, United Kingdom (UK), to investigate whether baseline attributions for MI were related to health‐related behaviour change at 6 months (N=132). Spouses (N=85) also completed the attribution questionnaire at baseline.

Results.There was no consistent relationship between the causal attributions of patients and subsequent behaviour change in Auckland and Brighton. For both samples, causal attributions were associated with pre‐MI behaviour.

Conclusions.The data from both samples suggest that the causal attributions of MI patients and their spouses may be realistic, but not predictive of subsequent changes in behaviour.
The DAS24: A short form of the Derriford Appearance Scale DAS59 to measure individual responses to living with problems of appearance
Authors: Carr Tony , Moss Timothy , Harris David
Published: May 2005

Objectives. To develop a psychometrically robust and widely applicable short form of the Derriford Appearance Scale, (DAS59), which (1) will reliably and validly assess the distress and difficulties experienced in living with problems of appearance, (2) is acceptable to clinical and non‐clinical populations, and (3) facilitates research and clinical decision‐making through good standardization and sensitivity.

Design. Cross‐sectional survey designs using clinical (out‐patient and in‐patient) and general population samples.

Method. Twenty‐five items were selected initially from the 59 items of the original DAS59. These were refined to 24 through item analyses and the scale was standardized on 535 patients with a range of problems of appearance and on a representative general population sample (N =1,107).

Results. All 24 items contributed well to the total score and internal consistency was high (α=.92). Test—retest reliability (6 months) was good (0.82), and criterion validity, with the DAS59, was excellent (0.88). Good construct validity was demonstrated in differences between (1) patient and general population samples, (2) members of the general population concerned and not concerned about their appearance, and (3) in patterns of convergent and divergent correlations with a range of established scales. The general population data revealed widespread concerns about appearance.

Conclusion. The DAS24 provides a widely applicable and acceptable short form of the original DAS59. It is psychometrically robust and discriminates well between patient groups, between clinical and non‐clinical populations, and within the general population between those concerned, and those not concerned, about their appearance.
Border Wars: Literature, Politics, and the Public
Authors: Connolly Joy
Published: May 2005

Approaching Latin along the border line dividing the academic humanities from public discourse, this essay explores the possibility of articulating a publicly responsible practice of Latin literary studies. I suggest that the current eclecticism in literary studies well serves the project of democratic criticism at a time when the traditional raison d'Ãªtre of the university as the preserver of Euro-American culture is in decline. Next I draw on my current work on the republican tradition in literature and political thought, focusing on translations of Vergil by the 17th-century theorist James Harrington. The study of reception is a crucial part of renewing Latin studies for the new world, I suggest, because it reveals the role of Latin literature in shaping modern conceptions of the political, the aesthetic, and the relation between the two. Concluding, I turn briefly to Cicero, whose blurring of the political and the aesthetic calls into question our habits of thinking about the transition from Republic and Empire.
Persians as Centaurs in Xenophon's Cyropaedia
Authors: Johnson David M
Published: May 2005

Cyrus depends on the traditional virtues of the Persians, but must introduce a new understanding of virtue to make them an imperial people, coupling Median luxury with Persian restraint. The collapse of this unstable combination immediately following Cyrus' death is therefore natural enough. The Cyropaedia is thus a guide both to how to found an empire and to why not to found an empire.
Towards a DIAMEX process using high active concentrate. Production of genuine solutions
Authors: Serrano-Purroy Daniel , Christiansen Birgit , Glatz J.-P. , Malmbeck R. , Modolo G.
Published: May 2005

The efficiency of Minor Actinides (MA) recovery in the DIAMEX process has already been demonstrated using High Active Raffinate (HAR). The next step aims at the demonstration of reprocessing from High Active Concentrate (HAC) as feed, in view of an industrial application. The volume reduction would reduce the size of the installation to be used and thereby the costs of the process. The first step towards the demonstration of a DIAMEX process using HAC is the production of the genuine solutions. In the hot cell facility of ITU (Institute for Transuranium Elements), a HAR solution has been prepared, from small scale PUREX reprocessing of MOX fuel, and successfully subjected to a concentration/denitration process to obtain HAC. A final concentration factor (CF) of about 10 and an acidity of 4 M were reached. In the experiment a precipitate mainly composed of Sr, Zr, Mo, Sn and Ba was formed. MA precipitation was not significant (< 0.001%).
Einmodige Quantenkaskadenlaser für Anwendungen in der Spurengasanalytik (Single-Mode Quantum Cascade Lasers for Applications in Trace-Gas Sensing)
Authors: Mann Christian , Yang Q. , Fuchs F. , Bronner W. , Köhler K. , Wagner Joachim
Published: May 2005

Die vorliegende Arbeit befasst sich mit dem Entwurf, der Herstellung sowie der Charakterisierung von einmodigen DFB-Quantenkaskadenlasern für Anwendungen in der Spurengasanalytik. Die Laser eignen sich zur Detektion der fundamentalen Rotations-Schwingungs-Übergänge von Stickstoffmonoxid im Wellenlängenbereich um 5,35 μm (1870 cm−1) und von Kohlenmonoxid um 4,67 μm (2140 cm−1) mittels hochauflösender Absorptionsspektroskopie. Im Pulsbetrieb ist die Seitenmodenunterdrückung >27dB und die maximale Betriebstemperatur > 400K (127 °C). Typische Linienbreiten liegen bei etwa 100MHz.
Power Relations in Minoan Palatial Towns
Authors: Adams Ellen
Published: May 2005

The palatial towns of Knossos and Malia offer good comparable evidence for an investigation into how we can reconstruct prehistoric urban power relations. The author builds upon recent work on heterarchies and factional competition, but argues that, in the case of Neopalatial Crete, it is better to retain the term ‘hierarchy’ and introduce a more sophisticated approach to power relations than that offered by the traditional hierarchical model. This approach emphasises the need to contextualise the palaces in their urban setting in order to understand the interdependent relationship between various elites and non-elites. Furthermore, it undertakes multi-data analyses, since the correlations among formal distribution patterns inform us more about social strategies than any individual distribution pattern alone. The article concludes that not only were there different kinds of tiers and urban groups at each site, but also that the relationships between these groups were dissimilar.
Liquid Crystalline Elastomers
Authors: Zentel Rudolf
Published: May 2005

Today, material science is directed towards the development of multifunctional and oriented structures. One example of such supramolecular systems are liquid crystalline (LC) elastomers which combine the properties of LC phases (the combination of order and mobility) with rubber elasticity, one of the most typical polymer properties. Their most outstanding characteristic is their mechanical orientability; strains as small as 20% are enough to obtain a perfectly oriented LC monodomain. This orientability, if LC elastomers with chiral phases are used, leads, for example, to elastomers with chiral smectic C* phases which are likely to show piezo‐electric behavior.
Polymer optical fibers and nonlinear optical device principles
Authors: Groh W. , Lupo D. , Sixl H.
Published: May 2005

Basic principles of the present optoelectronic research activities at Hoechst AG are presented in this contribution. Within the diversified broad band spectrum of optoelectronic materials and applications our interest is focused on new types of polymer optical fibers and nonlinear optical device principles using organic Langmuir–Blodgett films and electrically poled polymers. The basic principles and the limits of the present research and development activities which, have a high market potential are outlined.
Monolayers and Langmuir–Blodgett multilayers of discotic liquid crystals?
Authors: Laschewsky André
Published: May 2005

The field of monolayer and multilayer films of discotic LCs is at its very beginning. The scope and limitations of this preparation method have not yet been explored, and little is known about the structures obtainable. However, the potential access to extraordinary, ordered thin films is fascinating, and will stimulate research in the future.
Low temperature deposition of a CaF2 insulator layer on GaAs
Authors: Vere A. W. , Mackey K. J. , Rodway D. C. , Smith P. C. , Frigo D. M. , Bradley D. C.
Published: May 2005

Multilayer semiconductor‐insulator structures composed of epitaxially grown layers of, for example, GaAs and CaF, have been the subject of widespread interest in recent years. The methods used to overcome lattice mismatch problems in order to obtain high quality insulator thin films are discussed along with photochemical decomposition methods for their production at low temperatures.
The synthesis and spectroscopic properties of organometallic cyanine analogues
Authors: Spotts James M. , Scaefer Willams P. , Marder Seth R.
Published: May 2005

Organometallic compounds with large transition dipole moments and small energy gaps are of potential interest as second‐ and third‐order nonlinear optical materials. Organometallic anaologues of cyanines with electropositive metal centers as the end groups, in which the electronic coupling between the transition metal and the organic fragment is strong, should lead to improved exinction coefficients and great potential in nonlinear optics applications.
JESSI—european microelectronics on its way
Authors: Grünewald Michael
Published: May 2005

The Joint European Submicron Silicon (JESSI) project provides Europes with an opportunity to become and remain competetive with the North American and Japanese performance in microelectronics development. Several of Europe's largest electronics companies are involved in the program which has an overall budget for 1992 or over 400 million ECU. The structure, achievements, and aims of the program which has just finished its start‐up phase, are presented.
Hydrogen in Semiconductors: Crystal growth and device processing
Authors: Pearton Stephen , Stavola Michael , Corbett James W.
Published: May 2005

The effects of unintentional hydrogen incorporation into both Si and III‐V materials during processing is likely to become more important as device dimensions are scaled down and even tighter control is required on the doping densities within the active and contact regions. Since hydrogen is a constituent of virtually every chemical reagent or gas that is used in semiconductor processing it is almost impossible to avoid near‐surface dopant passivation occurring during some of the processing steps. However, relatively low‐temperature heat treatments are effective in reactivating these dopants.
Direct writing of pure rhodium lines by laser induced chemical vapor deposition
Authors: Messelhäuser Johannes , Flint Edward B. , Suhr Harald
Published: May 2005

The deposition of thin rhodium lines of use in the electronics industry, for example as chip interconnections, is demonstrated using laser‐induced CVD and the rhodium precursor Rh(CO)2hfa (see figure). The deposited line exhibit a conductivity close to that of the bulk metal, and the precursor has a high vapor pressure leading to an attractively low deposition temperature.

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Magnetic interaction in an amide containing two separate nitroxyl radicals
Authors: Dulog Lothar , Wang Wei
Published: May 2005

Organic molecular magnets have been the target of synthetic chemists for sometime. Most nitroxyl radicals are paramagnetic compounds at high temperatures but magnetic susceptibility measurements indicate that a few such radicals exhibit frerromagnetism or ferromagnetic coupling. This paper deals with one such radical, a dinitroxylamide, which contains two unpaired electrons.
Fractals in conducting polymers
Authors: Aldissi Mahmoud
Published: May 2005

Talking point Do fractal concepts apply to conducting polymers? The strength of fractal analysis stems from its ability to characterize complex objects such as polymers in terms of fractal dimensionality and the fractal concepts encountered in irregular comlex systems are present in conducting polymers due to random growth and aggregation. A point of view is presented.
E‐MRS network coordinating national programs on advanced materials
Authors: Battistoni Claudio
Published: May 2005

An E‐MRS Network where the participants are those responsible for the national programs in advanced materials of various European countries, aimed at coordinating research efforts and presenting a unified front to the EEC is currently under Italian presidency. The President outlines the structure of the Network and presents its membership, its methods and aims.
CHEMFET Devices for biomedical and environmental applications
Authors: Barbaro Aurelio , Colapicchioni Claudio , Davini Enrico , Mazzamurro Giuseppina , Piotto Andrea , Porcelli Filippo
Published: May 2005

Chemically‐sensitive field effect transistors (CHEMFETS), modified with, for example, an ionophore embedde in an organic membrane, or with a biological receptor, are reviewed. The sensitivity and selectivity of the devices open up many applications in the biomedical field, for example an investigating the pH, glucose level, and sodium concentration in blood, and also in environmental monitoring where low concentrations of copper, cadmium and silver in water can be detected.
Superconductor thin films : In situ X‐ray study on the reaction of hydrogen with epitaxial YBa2Cu3O7 Layers
Authors: Schöllhorn Robert , Paulus Werner , Börner Ralph , Schubert Jürgen , Zander Wilhelm , Erxmaier Jeffrey , Weidinger Alois
Published: May 2005

The critical temperatures (Tcs) of superconducting oxocuprates are known to be correlated with the hole concentration. This can be in turn influenced by isomorphic substitution of cationic lattice constituents, the variation of the oxygen stoichiometry via thermal processes, or, as reported here, by reaction with hydrogen as the insertation of H should be equivalent to the extinction of a corresponding amount of holes. The reaction with hydrogen has been examined using in situ X‐ray diffraction.
Morphology of pentadecanoic acid monolayers at the air/water interface studied by BAM
Authors: Honig Dirk , Overbeck Gernot A. , Mobius Dietmar
Published: May 2005

Brewster angle microscopy (BAM) provides the opportunity to visualize birefringence and long‐range orientational order in floating monolayers with the advantage over fluorescence microscopy that no probe molecules are required. The Figure shows the hexagonal domains formed during the compression of pentadecanoic acid monolayers. The method and its potential are discussed.

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Conducting polymers as membranes with variable permeabilities for neutral compounds: Polypyrrole and polyaniline in aqueous electrolytes
Authors: Schmidt Volkmar M. , Tegtmeyer Dietrich , Heitbaum Joachim
Published: May 2005

A combination of mass spectrometry and cyclic voltammetry has proved a powerful tool for the simultaneous study of the structure changes and membrane properties of conducting polymers. The oxidized state of polypyrrole and the emeraldine structure of polyaniline, the two materials used in the study, are shown in the Figure.

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Diamond from fullerenes
Authors: Regueiro Manuelnúñez
Published: May 2005

Buckminsterfullerene has been enjoying intense attention from physicists and chemists alike in an attempt to modify and examine it in every possible way. Realistic applications for this form of carbon are, however, few and far between. Recently a group based in Grenoble have shown that it is possible to convert C60 (see Figure) into diamoned. The process and its consequences are discussed.

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European action on organic superconductors
Authors: Jérome Denis , Bechgaard Klaus
Published: May 2005

Organized, coordinated research efforts into organic superconductors, centered around the groups in Orsay (France) and Copenhagen (Denmark) have resulted in considerable progress in the field. The European Commission (DC XIII) set up a consortium in 1989 involving Denmark's Portugal and France to further exploit cooperative links. The consortium is known as MOL‐COM, from MOLecular COmponents for Microelectronics and its activities and achievements are described by two of its leading participants.
Ab‐Initio computer modeling of semiconductor surfaces
Authors: Srivastava Gyaneshwar P. , Jones Bob
Published: May 2005

The equilibrium atomic structure of semiconductor surfaces, their electronics states and vibrational properties can be calculated using ab‐initio theoretical methods. The difference in the surface as opposed to the bulk properties of semiconductors is one of the reasons for their usefulness in, for example, infrared detectors or very large scale integrated (VLSI) circuits. The applications of the theoretical methods are discussed and their agreement with experiment assessed.
Tetraphenylporphyrins as coupling reagents and corrosion inhibitors
Authors: Meyer‐Roscher Bernd , Siemens Thomas , Brockmann Hans
Published: May 2005

The irreversible protection of iron surfaces with metalloporphyrins through electrolysis is reported. Tetraphenyl porphyrins (see figure) are also shown to exhibit a corrosion‐inhibiting effect when iron samples coated with the various porphyrin derivatives are treated with 5% sulfuric acid.

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Disordered stripe domain phases in two dimensions: “Labyrinths” and “stripe liquids” in magnetic and organic thin films
Authors: Seul Michael
Published: May 2005

Amphilic “Langmuir” monolayers, thin layers of type‐I superconductors ferromagnetic colloids (ferrofluids), and ferroelectrics are just some of the materials in which domains patterns, such as the labyrinthine stripe domain in a ferrimagnetic garnet film (see figure), and their evolution in response to changing experimental parameters are discussed.

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Atomistic modeling of materials properties by Monte Carlo Simulation
Authors: Binder Kurt
Published: May 2005

In order to optimize materials properties, in many cases a deeper understanding of the relationship between the chemical‐atomistic structure and the physical properties of the solid and fluid phases of the material is necessary. Monte Carlo simulation is a tool that allows the reliable calculation of thermodynamic properties of strongly interacting many‐body condensed matter systems. Given a model of effective interatomic or intermolecular interactions (drawn either from quantum‐chemical‐type interactions or from analysis of suitable experimental data), macroscopic bulk properties of a material can be simulated, as well as interfacial phenomena and certain kinds of slow dynamic processes (of relaxational or diffusive type). After a brief review of the foundations of this approach in statistical mechanics, the wide potential of this method is illustrated with examples taken from magnetism, metallurgy and amorphous polymeric materials. Strengths and limitations of this atomistic approach towards modeling materials properties are discussed and directions of future research are spelled out.
Spin–spin coupling between the two unpaired electrons in bis(tetrathiafulvalenyl)ketone dications
Authors: Sugimoto Toyonari , Yamaga Seiji , Nakai Makoto , Nakatsuji Hiroshi , Yamauchi Jun , Fujita Hideo , Fukutome Hideo , Ikawa Atsushi , Mizouchi Hideo , Kai Yasushi , Kanehisa Nobuko
Published: May 2005

In the search for stable organic ferromagnets, well‐characterized one‐ and two‐dimensional high‐spin organic oligomers and polymers are of great interest. Here, the synthesis of the title compounds (see Figure) is reported and the nature of the dication ground state is discussed based on theoretical and experimental studies.

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Conductive polymer/high‐temperature superconductor composite structures
Authors: Haupt Steven G. , Riley David R. , McDevitt John T.
Published: May 2005

High‐Tc superconductors and conducting polymers can be used to form composite structures that exhibit interesting properties (the Figure shows polypyrrole grown on YBa2Cu3O7‐δ). The polymers can be used to control the electrical properties of the thin film superconductor structure.

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Fabrication of organic nanocrystals for electronics and photonics
Authors: Nalwa Hari Singh , Kakuta Atsushi , Mukoh Akio , Kasai Hitoshi , Okada Shuji , Oikawa Hidetoshi , Nakanishi Hachiro , Matsuda Hiro
Published: May 2005

We have presented a simple technique for the fabrication of nanocrystals of organic molecules and polymers and have shown that it is possible, using the liquid‐phase technique, to fabricate organic nanocrystals ranging in size from 10 nm to 1 μm by manipulating the preparative conditions. In particular, nanocrystals of poly(4‐BCMU) ranging from 20 nm to 350 nm were prepared by controlling the preparation conditions. The main advantages of the liquid‐phase technique are the practicality and suitability of the technique for a wide range of materials. The fabrication of organic nanocrystals, though at a very early stage, seems a promising approach for producing low‐dimensional organic materials and, like inorganic nanocrystals, another important objective for future study would be to incorporate organic nanocrystals into a variety of inorganic and organic media. It is hoped that extensive work will be done on organic nanocrystals to evaluate their potential for electronics and photonics.
Microwave syntheses of inorganic materials
Authors: Mingos D. Michael P.
Published: May 2005

Microwave processing is a relatively new technique for chemical syntheses, and it is proving to be more widely applicable than could have been imagined even just five years ago. After a brief introduction to the theory, this article presents the advantages of microwave dielectric heating and discusses applications to solid‐state oxides, superconductors, fine metal powders, and semiconductors. The speed of the reaction is often impressive, and the phenomenon of “thermal runaway”, despite its name, can be helpful rather than a nuisance.
Magnetic properties of polyoxovanadates: Magnetic confirmation of the valence state of the vanadium centers in Na6[H6 V12O30F2] · 22H2O
Authors: Müller Achim , Rohlfing Ralf , Barra Anne‐Laure , Gatteschi Dante
Published: May 2005

Oxovanadium clusters are intersting both as moels of bulk magnets and in their own right. Results are presented suggesting that in Na6[H6V12O30F2]·22H2O (see Figure) it is meaningful to decide which particular vanadium centers should be considered at 5⊕ and which as 4⊕. It is shown that in principle ist is possible to tune and design the topology, and thus the magnetic properties, of polyoxovanadates(IV/V) by means of the template effect.

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Kinetics of the intercalation of cations into MnPS3 using real time in situ x‐ray diffraction
Authors: Evans John S. O. , O'hare Dermot
Published: May 2005

Intercalation in transition metal hexathiohypodiphosphates (MPS3), which proceeds by a unique ion‐exchange route, is not well understood because it is difficult to follow the process in real time. Using a recently developed technique that allows the X‐ray diffraction pattern of a suspension of an inorganic host lattice in a solution of guest molecules to be recorded in as little as 10 s, the intercalation of cationic species into MnPS3 has been investigated. The analysis of the kinetics at various temperatures is presented.
An open‐framework zinc phosphate with ZnOZn linkages
Authors: Song Tianyou , Hursthouse Michael B. , Chen Jiesheng , Xu Jianing , Malik K. M. Abdul , Jones Richard H. , Xu Ruren , Thomas John Meurig
Published: May 2005

Open framework crystalline solids have great potential as catalysts and absorbers and for many other applications in materials science. The synthesis and structural characterization of a new zinc phosphate prepared from a predominantly non‐aqueous system are described. The unique features of the compound, which has the empirical formula Zn4(PO4)3(H2O)(C2H5NH3), such as three‐coordinated oxygen atoms and a ratio of Zn to P greater than 1, are discussed.
Mechanical properties of Ultrahigh Boron Steels
Authors: Jiménez José A. , González‐Doncel Gaspar , Ruano Oscar A.
Published: May 2005

A fine and stable grain size in steelresults in greatly improved mechanical properties. In analogy to the addition of larger quantities of carbon to form ultra‐high carbon steels, the formation of borides in steel through rapid solidification and powder metallurgical techniques leads to the required grain size (see Figure) The materials processing, microstructure control, and properties of the materials are reviewed.

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Synthesis of regioregular poly(methyl pyridinium vinylene): An isoelectronic analogue to poly(phenylene vinylene)
Authors: Marsella Michael J. , Fu Dian‐Kui , Swager Timothy M.
Published: May 2005

Poly(phenylene vinylene), PPV, and its derivatives have generated much interest due to their high conductivity and electroluminescent properties which allow for LED applications. Highly electron‐deficient PPV analogues are desirable as they would allow the use of environmentally stable metals as the electrodes in the LEDs. The title compound (see Figure) is just such as material.

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Extraction of aqueous gold sols with styrene/2‐vinylpyridine block copolymers in toluene
Authors: Roescher G. Arno , Möller Martin
Published: May 2005

Polymers containing small noble‐metal particles are of interest for catalysis and in the generation of optically tunable composites. The currently used process results in materials which are often difficult to process. A method is presented here for the direct transfer of small gold particles from an aqueous sol into a non‐aqueous polymer solution (e.g. a block copolymer, see Figure) facilitating the formation of films.

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Optical properties of Pr3⊕ ions in fluoride glasses
Authors: Alcalá Rafael , Cases Rafael
Published: May 2005

Materials for near‐infrared optical fiber amplifiers are currently receiving considerable attention, and the spectroscopic properties of rare‐earth ions in heavy metal fluoride glasses make them prime candidates for amplifiers in the second transmission window of silica fibers (at 1300 nm). The background to this technology is presented and requirements for future improvements discussed.
Advanced multiphase magnetic systems
Authors: Vázquez Manuel , Hernando Antonio
Published: May 2005

The co‐existence of different magnetic phases, (i.e. ferromagnetic, antiferromagnetic, paramagnetic) mixed on a nanostructure scale has a profound influence on the soft/hard magnetic behavior of the materials. The effects of thermal treatment of these multiphase systems has been examined and a strong interdependence found between the nanosructure and the exchange correlatio length.
Ferromagnetic interactions in organic/molecular materials
Authors: Veciana Jaume , Cirujeda Joan , Rovira Concepció , Vidal‐Gancedo José
Published: May 2005

Hydrogen bonding has been used as a crystalline design element in the synthesis of new organic molecular‐based magnets. The H bonding controls not only the crystal packing of the organic open‐shell molecualr solids ut also generates ferromagnetic interactions and propagates them along predetermined spatial directions. The background of molecular magnetism and the details of this new strategy are discussed.
The national science foundation advanced materials and processing program
Authors: Lapporte Seymour J.
Published: May 2005

The national science foundation (NSF) has been providing support for materials science research since 1972. The interacting components making up NSF's Advanced Materials and Processing Program, which began initially as a federal initiative in 1993, are described. The goals, levels and modes of support are briefly discussed, whereby the importance of partnerships, particularly between university, industrial and government laboratories, is emphasized. The article concludes with a look into the future.
Surface acoustic wave chemical microsensors based on covalently bound self‐assembled host monolayers**
Authors: Moore Louie W. , Sprjnger Kendall N. , Shi Jing‐Xuan , Yang Xiaoguang , Swanson Basil I. , Li Dequan
Published: May 2005

Novel asymmetric cyclodextrin derivatives have been synthesized. The materials form self‐assembled host monolayer thin films under the action of silane coupling reagents. Ultrasensitive (low‐ppm) sensors for volatile organic compounds have been developed based on these and related materials, and it is suggested that pattern recognition with an array of such sensors could be a feasible approach to the identification of a particular organic material.
Mesomorphous polyelectrolyte‐surfactant complexes
Authors: Antonietti Markus , Burger Christian , Effing Jochem
Published: May 2005

Polyelectrolyte–surfactant complexation allows the design and synthesis of a variety of highly ordered materials (sch as that modeled in the Figure). The variation of the polyelectrolyte and surfactant properties enables the tuning of the mechanical, electrical, and optical properties of the materials. The highly ordered media produced could be combined with a number of functional componentn (e.g., NLO dyes, conducting subunits, or gas selective groups)

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Electrochemically polymerizable self‐assembled monolayers
Authors: Willicut Robert J. , McCarley Robin L.
Published: May 2005

Surface‐confined monomer‐containing monolayers based on pyrroles on an electrode offer the possibility for a high level of control over the electrochemical polymerization of the monomers within the monolayer. This is of importance for the development of molecular‐scale electronic devices. The materials and the technique of surface‐confined polymerization are presented.
Glass‐encapsulated molecular wires: A polypyrrole/porous glass composite*
Authors: Maia Daltamir J. , De Paoli Marco‐A , Zarbin Aldo Jose G. , Alves Oswaldo L.
Published: May 2005

The production of molecularly isolaed polymers as molecular wires is a method of controlling the factors, such as microstructure, morphology, counter‐ion, etc., which influence the properties of the material. Here, porous Vycor glass is used as the host material, Cu2⊕ ions which have been previously introduced into the 20–200 Å pores promoting the polymerization of pyrrole by reduction. The synthesis and properties of the new material are presented.
LEDs based on poly(p‐phenylenevinylene) and polyimide LB films
Authors: Wu Aiping , Kakimato Masa‐aki
Published: May 2005

Highly ordered organic thin films with well defined film thicknesses produced using the Langmuir‐Blodgett technique can employed in the fabrication of ultra‐thin heterostructure devices. Heterostructure LEDs have been shown to exhibit superior performance characteristics. Recent progress is reviewed.
Optically Polarized 129Xe in NMR Spectroscopy*
Authors: Pietraiß Tanja , Gaede Holly C.
Published: May 2005

129 Xe has found widespread applications in NMR spectroscopy, but its use is often restricted by its low sensitivity and long relaxation times. Optical pumping of rubidium followed by spin exchange with xenon provides a well understood technique to enhance the 129 XePolarization by several orders of magnitude. The exploitation of this highly spin‐polarized xenon as a surface probe in NMR studies of various meterials is discussed. Applications of this technique make use not only of 129Xe NMR detection, but also of the‐high spin polarization as a magnetization reservoir for selective cross‐polarization experiments to surface nuclei. A diverse variety of materials has been studied, ranging from mesoscopic structures such as semiconductor nanocrystals and porous silicon to high surface area polymers.
Enhanced efficiency of polymer light emitting diodes utilizing oxadiazole polymers
Authors: Karg Siegfried , Rieß Walter , Schwoerer Markus , Buchwald Elke , Meier Martin , Pösch Peter , Rieß Walter , Schmidt Hans‐Werner , Strohriegl Peter , Schwoerer Markus
Published: May 2005

New oxadiazole polymers for use in LEDs are reported that have high thermal stability and excellent film‐forming properties. The characteristics of the polymers themselves and of heterolayer LEDs based on poly(phenylenevinylene) that incorporate the polymers as efficient elecron transport and injection layers are discussed. The stability, operating time and quantum efficiency are shown to be improved compared to monolayer devices.
Self‐assembled crystalline monolayers and multilayers of n‐alkanes on the water surface*
Authors: Weinbach Susan P. , Weissbuch Isabelle , Lahav Meir , Leiserowitz Leslie , Kjaer Kristian , Bouwman Wim G. , Als Nielsen Jens
Published: May 2005

The induced formation of multilayer crystallites at liquid interfaces provides a direct means of monitoring the dynamics of crystal nucleation and of elucidating the effect of molecular inhibitors on polymorphism and crystal growth. The spontaneous formation of crystalline multilayers of n‐alkanes spread from solution onto the water interface are described and X‐ray structural investigations discussed which indicate that the full crystal symmetry is present even in layers that are only a few unit cells thick.
Liquid crystalline oligomeric and polymeric phthalocyanines
Authors: Cook Michael J.
Published: May 2005

The many interesting properties of phthalocyanines (nonlinear optical behavior, redox properties, semiconductivity) have been extended to include liquid crystalline (LC) behavior since these compounds atracted the attention of syntehtic chemists. Approaches to the synthesis of polymeric LC phthalocyanines are described and their LC behavior briefly reviewed. Evidence is presented that the polymers develop columnar stacks that mimic those of simpler mesogens.
Third‐order nonlinear optical properties of thin films of organogermane homopolymers and organogermane‐organosilane copolymers*
Authors: Kodaira Takuo , Watanabe Akira , Ito Osamu , Matsuda Minoru , Tokura Satoshi , Kira Mitsuo , Nagano Shuh‐Saku , Mochida Kunio
Published: May 2005

σ‐conjugated polysilanes and polygermanes are known to possess interesting linear optical properties as well as unique physical and chemical properties. Unlike π‐conjugated carbon‐based polymers these materials are transparent in the visible and strongly absorbing in the near ultraviolet region. Here, the nonlinear optical properties, in particular those for third harmonic generation, for several polygermane homopolymers and a polygermane‐polysilane copolymer are presented.
Flexible arrays of submicrometer‐sized polymeric light emitting diodes
Authors: Granström Magnus , Inganas Olle
Published: May 2005

Arrays of small polymer‐based LEDs have been produced using a technique based on polymer self‐organization. The active component, a polybithiophene, is shown to form small (50–200 nm) islands in a PMMA matrix when the two materials are mixed in an appropriate ratio. These islands become light emitters when electron‐ and hole‐injecting contacts are applied. The generation of the arrays is described and the use of polymer‐based hole‐injecting contacts, which provide mechanical flexibility, is discussed.
Bis(ethylenethio)tetrathiafulvalene (BET‐TTF), an organic donor with high electrical conductivity
Authors: Rovira Concepciö , Tarrés Judit , Veciana Jaume , Rovira M. Carme , Novoa Juan J. , Yang Syaulan , Cowan Dwain O. , Canadell Enric
Published: May 2005

Molecular charge transfer salts based on the highly conducting organic donor BET–TTF and small inorganic anions are presented. How the conductivity of the donor is related to its crystal structure has been investigated and the properties of the organic metal CT salts are discussed.
Spontaneous magnetization in a 2:3 complex formed by 3,4′,5‐tris(N‐oxy‐tert‐butylamino)biphenyl and manganese(II)bis(hexafluoroacetylacetonate)
Authors: Iwamura Hiizu , Inoue Katsuya
Published: May 2005

The basic problem in the design of molecular magnets is how to assemble unpaired electrons and align their spins on the macroscopic scale. One line of investigation involves heterospin systems consisting of transition metal ions and organic free radicals as ligands. Results are reported for such a system (see figure) in which the heterospin system forms a 2‐D network, which increases Tc compared to a 1‐D network.

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Boron‐doped molybdenum silicides
Authors: Meyer Mitchell , Kramer Matthew , Akinc Mufit
Published: May 2005

Replacement materials for the superalloys currently used in gas turbine engines are needed if the operating temperature—and thus efficiency—is to be increased. Candidates include ceramics (which have problems with low fracture toughness) and intermetallics. The materials discussed here consist of a Mo5Si3 matrix combined with one or two other phases to increase the ductility and oxidation resistance. The oxidation behavior and creep behavior are examined, in particular upon the addition of boron.
Dye composite layers by physical vapor deposition
Authors: Jäger Steffen , Böttcher Horst
Published: May 2005

The embedding of dyes in metal halides, metal sulfides and metal oxides has become possible with the introduction of multi‐source physical vapor deposition (MSPVD). This in turn has led to potential applications such as colored layers, spectral sensitization of semiconductors and systems for controlled release of drugs. The technique of MSPVD is briefly described and the optical properties of the dye composite films are discussed.
Chirality in regioregular and soluble polythiophene: An internal probe of conformational changes induced by minute solvation variation
Authors: Bidan Gérard , Guillerez Stéphane , Sorokin Victor
Published: May 2005

Chirality has been used as an internal probe of structural changes accompanying micro‐aggregation of a soluble regioregular poly(alkylthiophene). First, the synthesis of new polythiophenes having long alkyl chains is described. The UV/vis and circular dichroic spectroscopy are shown to indicate that the transformation of a disordered species in solution into an ordered one in a micro‐aggregated state is a two‐step process. Tentative proposals are made about the nature of the intermediate state, which, however, remains unclear.
Unified crystal chemical model of high‐Tc superconductors: Complete chemical formulation and mechanism of generation of cooper pairs for K3C60 and La2 − xBaxCuO4 − δ
Authors: María José M.
Published: May 2005

A reliable quantitative physical theory of high‐Tc super‐conductivity is not yet available, partly because a suitable model of the chemical composition, structure, and bonding high‐Tc superconductors (HTSCs) does not exist. Here the basic premise required for such a model is presented: that in the normal state of HTSCs there are electrons trapped in metal – metal bonds. Detailed chemical formulae (i.e., including metal‐metal bonding electron) are obtained for the superconducting systems K3C60 and La2−xBaxCuO4 − δ and interpreted in terms of donor–acceptor electron charge transfer.
Mapping the elemental distribution in sol‐gel derived ceramics
Authors: Houk Carol S. , Page Catherine J.
Published: May 2005

Elemental dispersive x‐ray (EDX) composition distribution mapping using a scanning electron microscope (SEM) provides information about samples that is complementary to that obtained from X‐ray diffraction. Examples are given (e.g., Ba and Cu maps of YBa2Cu3O7 − δ, see figure) to demonstrate the usefulness of this technique in evaluating the homogeneity of sol‐gel products and in elucidating elemental zoning (see also cover picture).

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Centrosymmetric molecules for second harmonic generation
Authors: Ashwell G. J.
Published: May 2005

The requirement of a non‐centrosymmetric structure for second harmonic generation (SHG) was until recently assumed necessarily to apply to te smallest building block, the molecule. However, non‐centrosymmetric aggregates of centrosymmetric molecules can exist, and their SHG properties are considered here. Derivatives of squaraines are taken as examples. Finally, the role of intermolecular charge transfer in Langmuir–Blodgett film‐forming materials for SHG—both within the monolayers and across the boundary—is discussed.
The electronic structure of solid α‐sexithiophene
Authors: Taliani Carlo , Blinov Lev M.
Published: May 2005

The properties of α‐sexithiophene (α‐T6), e.g., the pronounced one‐dimensionality of the molecule (see Figure), the layered crystal packing, and the low exciton binding energy, make it a very interesting material for electronic and optoelectronic applications. Investigations into the origin of its optical gap and conclusions drawn from them are reported.

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Five‐membered heteroaromatic hydrazone derivatives for second‐order nonlinear optics
Authors: Wong Man Shing , Meier Urs , Pan Feng , Gramlich Volker , Bosshard Christian , Günter Peter
Published: May 2005

Highly efficient frequency conversion in crystalline organic molecules for opto‐electronic applications is the aim of the investigation reported here into how various heteroatomic rings affect molecular nonlinearity. The optical properties of hydrazone derivatives with the furan or thiophene moiety as part of the conjugated core are described, and 5‐(methylthio)thiophenecarboxaldehyde‐4‐nitrophenyl‐hydrazone (MTTNPH) is demonstrated to have the properties required.
The exciton binding energy in luminescent conjugated polymers
Authors: Brédas Jean‐Luc , Cornil Jérôme , Heeger Alan J.
Published: May 2005

Luminescence in organic conjugated polymers is considered in this article, which tries to clarify some of the issues related to the nature of the emitting species. A comparison of recent experimental and theoretical data on the exciton binding energy in luminescent poly(arylenevinylene)s, polyarylenes, and their derivatives (e.g., see Figure) leads to he conclusion that they sustain rather weakly bound polaronexitons.

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European consortium on nanomaterials
Authors: Dutta Joydeep , Hofmann Heinrich , Schmid Günter
Published: May 2005

The European Consortium on Nanomaterials, which was founded earlier this year, brings together research groups from academia and industry from ten European countries with the aim of promoting the development of nanonstructured materials. The main objectives of the consortium and its working groups are outlined, the common features of nanomaterials are discussed, and the factors that need to be controlled in order to be able to tailor the properties of the materials are sketched. See the following Essay for details of another activity connected with nanomaterials.