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New Phase (new + phase)
Selected AbstractsChemInform Abstract: Explorations of New Phases in the GaIII/InIII,CuII,Se IV,O System.CHEMINFORM, Issue 39 2009Fang Kong Abstract ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a "Full Text" option. The original article is trackable via the "References" option. [source] Three New Phases in the K/Cu/Th/S System: KCuThS3, K2Cu2ThS4, and K3Cu3Th2S7.CHEMINFORM, Issue 47 2005Hugh D. Selby Abstract For Abstract see ChemInform Abstract in Full Text. [source] New Phases in the Lithiumnitridovanadate System , The Solid Solution Li7-2xMgx[VN4] with 0 , x , 1.CHEMINFORM, Issue 19 2004Rainer Niewa Abstract For Abstract see ChemInform Abstract in Full Text. [source] New phases of thermal SYM and LST from Kaluza-Klein black holesFORTSCHRITTE DER PHYSIK/PROGRESS OF PHYSICS, Issue 7-8 2005T. Harmark Abstract We review the recently found map that takes any static and neutral Kaluza-Klein black hole, i.e. any static and neutral black hole on Minkowski-space times a circle ,d × S1, and maps it to a corresponding solution for a non- and near-extremal brane on a circle. This gives a precise connection between phases of Kaluza-Klein black holes and the thermodynamic behavior of the non-gravitational theories dual to near-extremal branes on a circle. In particular, for the thermodynamics of strongly-coupled supersymmetric Yang-Mills theories on a circle we predict the existence of a new non-uniform phase and find new information about the localized phase. We also find evidence for the existence of a new stable phase of (2,0) Little String Theory in the canonical ensemble for temperatures above its Hagedorn temperature. [source] Theoretical Prediction of Post-Spinel Phases of Silicon NitrideJOURNAL OF THE AMERICAN CERAMIC SOCIETY, Issue 1 2002Kazuyoshi Tatsumi New phases of Si3N4 that may be stable at higher pressure than spinel have been searched using a first-principles plane-wave pseudopotential method. The CaTi2O4 -type phase is found to be the prime candidate for the post-spinel phase among six phases selected on the analogy to high-pressure oxides. The phase transformation from the spinel is predicted to occur at 210 GPa. All silicon atoms of the new phase are coordinated by six anions, similar to the case of the high-pressure forms of SiO2 and SiC. Because of its high energy at zero pressure, this new phase may be difficult to quench. The bandgap increases with an increase of pressure when compared in the same polymorph. However, the bandgap and the net charge decrease in the order of ,, spinel, and CaTi2O4 -type phases at zero pressure. The theoretical bulk modulus of the CaTi2O4 -type phase is comparable with that of spinel. [source] Effect of micro mass transfer through phase interface on numerical simulation of solidification processHEAT TRANSFER - ASIAN RESEARCH (FORMERLY HEAT TRANSFER-JAPANESE RESEARCH), Issue 6 2004Yanhui Feng Abstract Existing models for the solute redistribution during solidification have been reviewed. Some typical models are applied for the numerical simulation of heat and mass transfer with phase change under experimental condition of inverse casting. The results show that the effect of micro mass transfer models on the formation of the new phase cannot be omitted. © 2004 Wiley Periodicals, Inc. Heat Trans Asian Res, 33(6): 393,401, 2004; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/htj.20024 [source] The Third World Water Forum: to translate visions into concrete actions and commitmentsHYDROLOGICAL PROCESSES, Issue 11 2002Hideaki Oda Abstract Water is vital for the life and health of people and ecosystems and a basic requirement for the development of countries, but many people lack access to adequate and safe water to meet their most basic needs. Water resources, and the related ecosystems, are now under threat from pollution, unsustainable use, climate change, and many other forces. The World Water Forum series has been likened to a series of stepping stones towards the solution of the world's pressing water problems. Each step constitutes a new phase. The third World Water Forum takes up the World Water Vision created at the second World Water Forum in The Hague in 2000, and sets out to see that vision realized in concrete actions. Copyright © 2002 John Wiley & Sons, Ltd. [source] The politics of Europe 2002: flexibility and adjustmentINDUSTRIAL RELATIONS JOURNAL, Issue 5 2003Erik Jones The European Union entered a new phase of integration in 2002. The single currency, the European Convention, and enlargement signalled progress. The conflict over the Stability and Growth Pact, the tensions between the member states, and the political turmoil in a number of core countries suggested retreat. This paper examines the resulting pattern of integration. It argues that the European Union is becoming more legalistic than leader-oriented, and that it rests on common principles rather than accepting the imposition of some grand design. Such a European Union cannot challenge the United States for global leadership. But it is likely to prove stable nonetheless. [source] Direct Synthesis of New Zircon-Type ZrGeO4 and Zr(Ge,Si)O4 Solid SolutionsJOURNAL OF THE AMERICAN CERAMIC SOCIETY, Issue 8 2002Masanori Hirano A new phase of ZrGeO4 was hydrothermally synthesized from a mixture of ZrOCl2 solution and GeO2 powder at 240°C. X-ray diffractometry patterns of synthesized ZrGeO4 particles, which had better crystallinity than ZrSiO4 particles prepared by the same process from ZrOCl2 and tetraethoxysilane, could be indexed for a zircon-type tetragonal structure, having a0= 0.6694(0) and c0= 0.6265(7) nm. The c/a ratio of synthesized ZrGeO4 (0.9360) was larger than that of ZrSiO4 (0.9054). Solid solutions with zircon-type structure over the whole composition range in the ZrGeO4 -ZiSiO4 system were also directly synthesized through the same solution route. The secondary particle size of zircon-type Zr(Ge,Si)O4 solid solutions decreased, and its morphology gradually changed from octahedron-like to blood-red cell-like with decreased GeO2 content. [source] Theoretical Prediction of Post-Spinel Phases of Silicon NitrideJOURNAL OF THE AMERICAN CERAMIC SOCIETY, Issue 1 2002Kazuyoshi Tatsumi New phases of Si3N4 that may be stable at higher pressure than spinel have been searched using a first-principles plane-wave pseudopotential method. The CaTi2O4 -type phase is found to be the prime candidate for the post-spinel phase among six phases selected on the analogy to high-pressure oxides. The phase transformation from the spinel is predicted to occur at 210 GPa. All silicon atoms of the new phase are coordinated by six anions, similar to the case of the high-pressure forms of SiO2 and SiC. Because of its high energy at zero pressure, this new phase may be difficult to quench. The bandgap increases with an increase of pressure when compared in the same polymorph. However, the bandgap and the net charge decrease in the order of ,, spinel, and CaTi2O4 -type phases at zero pressure. The theoretical bulk modulus of the CaTi2O4 -type phase is comparable with that of spinel. [source] Behavior of Silver and Palladium Mixtures during HeatingJOURNAL OF THE AMERICAN CERAMIC SOCIETY, Issue 11 2000Terry Garino The behavior of mixtures of silver and palladium during heating in both air and an inert atmosphere was studied using X-ray diffractometry (XRD), thermogravimetric analysis (TGA), differential scanning calorimetry (DSC), dilatometry, and scanning electron microscopy (SEM). In situ high-temperature XRD studies on a commercial 20% palladium material with submicrometer-sized particles indicated that an intermetallic phase, most likely Ag3Pd, formed in air between 300° and 400°C, the same temperature range where a 13% linear expansion was measured by dilatometry. The DSC data indicated an exothermic peak at 340°C, a temperature where the TGA results indicated that the material had picked up only 0.2% oxygen, compared with the maximum of 1.4% at 525°C. No PdO was detected by XRD at 400°C, which suggests that oxygen was being incorporated in the intermetallic. Microstructural examination using SEM indicated that larger particles, with internal pores, had formed after heating in air to 375°C. When the material was heated in argon for 1 h at 400°C, no intermetallic phase or alloy formed, and minimal expansion occurred. When mixtures of larger silver particles (5,30 ,m) with palladium particles (1,3 ,m) were heated in air, the maximum amount of expansion that occurred increased from 0% for pure palladium up to a maximum of 18% at 75% silver. This result supports the conclusion that expansion is a result of formation of this new phase, in the presence of oxygen, not of the oxidation of the palladium. [source] A phenomenon of waiting time in phase change problems driven by radiative heat transferMATHEMATICAL METHODS IN THE APPLIED SCIENCES, Issue 9 2009A. Fasano Abstract In the paper (J. Food Process Eng. 2008; in press) we emphasized that during a phase change process in which the heat input is driven by a radiation transfer mechanism, a peculiar phenomenon may occur, characterized by a temporary stop of the increase of the boundary temperature due to a sudden change of the heat transfer coefficient upon phase transition. This time interval is needed to allow the thermal properties of the surface to evolve toward a state that is compatible with the heat intake rate corresponding to the new phase. The occurrence of the waiting time is motivated and studied for a general one-dimensional Stefan problem. Then an application is presented to the much complicated problem considered in (J. Food Process Eng. 2008; in press), namely, the model for frying process. Copyright © 2008 John Wiley & Sons, Ltd. [source] Practicing Anthropology in a Time of Crisis: 2009 Year in ReviewAMERICAN ANTHROPOLOGIST, Issue 2 2010Keri Vacanti Brondo ABSTRACT, The breadth and reach of practicing anthropologists in 2009 suggests that anthropology has entered a new phase of advanced engagement at local, national, and international levels. In this article, I review thematic areas in which practicing anthropologists made significant contributions in 2009, including fiscal crisis and business anthropology; U.S. race relations, civil rights, and policy reforms; human rights, environmental change, and displacement; global health and human rights; and war and peace. New areas of expansion are also discussed in the arenas of public archaeology, museums and heritage, and engaged scholarship. Innovations in anthropological research and communicating ethnographic findings with the broader public are reviewed. [source] Changes in the life of PDS,The start of a new phasePHARMACOEPIDEMIOLOGY AND DRUG SAFETY, Issue 8 2010Brian L. Strom Editor-in-Chief First page of article [source] Observation of developmental processes in loosely attached diatom (Bacillariophyceae) communitiesPHYCOLOGICAL RESEARCH, Issue 2 2000Akihiro Tuji SUMMARY The succession of attached algal communities was studied in Lake Biwa and the Omiya River. After the ,climax' which was characterized by large numbers of Cymbella turgidula Grunow and Gomphoneis quadripunctatum (Østrup) P. Dawson, the community was dominated by species attached directly to stalks or tangled among stalks. Stalks produced by species of the previous phase are important as secondary substrata. The dominant species of the new phase were ,loosely attached species', as defined by Hudon and Bourget (1983). I propose a new model consisting of phase 1, characterized by the first colonizers, including large rosette-type species and motile type species; phase 2, characterized by the stalk-producing species; and phase 3, characterized by the growth of loosely attached species. [source] Power law specific heat divergence in Sr3Ru2O7PHYSICA STATUS SOLIDI (B) BASIC SOLID STATE PHYSICS, Issue 3 2010A. W. Rost Abstract We present measurement and analysis of field-dependent specific heat measurements on Sr3Ru2O7, showing that, at low temperatures, an incipient divergence is cut off by the formation of a new phase previously identified to show the transport properties of an electronic nematic. We discuss how to interpret a specific heat divergence in a system with van Hove singularities, and caution against a simple-minded comparison of experimentally determined power laws with the predictions of quantum critical theories. [source] Phase transitions in Sm1,xSrxMnO3 single crystals (0 , x , 0.8)PHYSICA STATUS SOLIDI (B) BASIC SOLID STATE PHYSICS, Issue 2 2003V. Yu. Abstract Magnetic and electrical properties of Sm1,xSrxMnO3 (0 , x , 0.8) single crystals have been studied and the T , x phase diagram has been revised. The compensation points of spontaneous weak ferromagnetic moment have been observed for pure SmMnO3 and for low doped compositions (0 , x < 0.05). For 0.4 , x , 0.475 the ferromagnetic ordering occurs as a first-order phase transition. It is shown that in a magnetic field the temperature of this transition increases and the transition becomes broader, which results in the appearance of a critical point (Tcr , 193 K, Hcr , 68 kOe for x = 0.45). Another transition, accompanied by a reduction of magnetization and noticeable anisotropy of magnetization curves, has been observed at low temperature Ts , 40 K. Below the Neel temperature, a pure antiferromagnetic state without spontaneous magnetization has been observed for 0.5 , x , 0.575, while for 0.6 , x , 0.675 an additional low-temperature transition to a new phase with a non-zero weak-ferromagnetic moment has been found. [source] Spirit possession, power, and the absent presence of Islam: re-viewing Les maîtres fous,THE JOURNAL OF THE ROYAL ANTHROPOLOGICAL INSTITUTE, Issue 4 2006Paul Henley In the history of ethnographic documentary, the late Jean Rouch's film Les maîtres fous is widely regarded as initiating a new phase in the development of the genre. It concerns the hauka spirit-possession cult of Songhay-Zerma migrants from the middle Niger river who had come to work in Accra, then the capital of the British colony of the Gold Coast, West Africa. When released in 1955, the film was both banned by the colonial authorities and simultaneously denounced by African intellectuals and leading French anthropologists. Since then it has gone through a progressive rehabilitation and today, some fifty years on, it is hailed in many sources as a remarkable counter-hegemonic representation of European colonialism in Africa. This article proposes a re-interpretation of Les maîtres fous, arguing that in order to defend the film against criticism, its counter-hegemonic features have been over-emphasized, thereby obscuring its continuity with other forms of Songhay-Zerma religious belief and practice. The article concludes with some brief reflections on the place of film in anthropology. [source] EuI2, a low-temperature europium(II) iodide phaseACTA CRYSTALLOGRAPHICA SECTION C, Issue 10 2009Michael Krings Light-yellow europium(II) diiodide, prepared by the low-temperature reaction of europium and ammonium iodide in liquid ammonia at 200,K and characterized by high-resolution X-ray powder diffraction, represents a new phase for EuI2 that adopts an orthorhombic Pnma structure with all three atoms lying on 4c positions (.m.). It is isotypic with SrI2(IV). Temperature-dependent X-ray measurements performed to investigate the thermal stability of the new phase show that it decomposes irreversibly to amorphous material around 673,K. Total-energy density-functional calculations using the generalized gradient approximation suggest this to be the ground-state structure of EuI2. [source] Metagenomic studies reveal the critical and wide-ranging ecological importance of uncultivated archaea: the role of ammonia oxidizersBIOESSAYS, Issue 1 2007Ricardo Cavicchioli Microbial genome sequencing has entered a new phase, where DNA sequence information is gathered from entire microbial communities (metagenomics or environmental genomics) rather than from individual microorganisms. By providing access to the genetic material of vast numbers of organisms, most of which are organisms that have never been isolated or cultivated, a new level of insight is being gained into the diversity and extent of the microbial processes that are presently occuring in environmental communities. By extending metagenomic-based approaches to the study of very complex and methodologically recalcitrant soil environments, a recent study has found that ammonia-oxidizing archaea are more abundant in many soils than bacteria.1 These findings not only highlight the undoubtedly critical yet unknown roles that archaea play in global nutrient cycles but illustrate the importance of genomic studies for informing us about the functional capacity of life on Earth. BioEssays 29: 11,14, 2007. © 2006 Wiley Periodicals, Inc. [source] Viral technology enters a new phaseBIOTECHNOLOGY & BIOENGINEERING, Issue 2 2007Article first published online: 23 APR 200 No abstract is available for this article. [source] Leveraging mobile technology for sustainable seamless learning: a research agendaBRITISH JOURNAL OF EDUCATIONAL TECHNOLOGY, Issue 2 2010Chee-Kit Looi Over the next 10 years, we anticipate that personal, portable, wirelessly networked technologies will become ubiquitous in the lives of learners,indeed, in many countries, this is already a reality. We see that ready-to-hand access creates the potential for a new phase in the evolution of technology-enhanced learning, characterised by ,seamless learning spaces' and marked by continuity of the learning experience across different scenarios or contexts, and emerging from the availability of one device or more per student. The challenge is to enable learners to learn whenever they are curious and seamlessly switch between different contexts, such as between formal and informal contexts and between individual and social learning, and by extending the social spaces in which learners interact with each other. In this paper, we review the potential of mobile learning research for designing seamless learning environments that can bridge both formal and informal learning, present a research agenda and discuss important methodological issues that concern research into formal and informal learning. [source] Developing the role of schools as research organisations: the Sunfield experienceBRITISH JOURNAL OF SPECIAL EDUCATION, Issue 2 2007Barry Carpenter We are entering a new phase in learning about childhood disabilities. While we have found out much of what we need to know about their causes and aetiology, solutions to many of the challenges we will face in the future will come from the evidence base held by practitioners. Practitioners are ideally placed to carry out ,real world' research but they often need support in carrying out setting-based enquiry. In this article, Barry Carpenter, Chief Executive and Director of Research at Sunfield, discusses the relationship between academic and practitioner research and the role of practitioners as researchers. He goes on to explore the development of a research culture in special schools, focusing on Sunfield, a residential special school for children with severe and complex learning disabilities. Barry Carpenter shows how research projects at Sunfield have generated evidence which has guided the school's development. The inter-disciplinary approach adopted in this setting has encouraged involvement in research from many staff in diverse professions throughout the school. [source] Police Reform and the Peace Process in Guatemala: the Fifth Promotion of the National Civilian PoliceBULLETIN OF LATIN AMERICAN RESEARCH, Issue 4 2001Marie-Louise Glebbeek After 36 years of mostly authoritarian rule and often bitter civil conflict in Guatemala, the December 1996 Peace Accords prepared the ground for a new phase of reconstruction, democratisation and social and institutional reform. Prior to the Peace Accords, policing in Guatemala had been often violent, repressive and subordinated to the counterinsurgency logic of the military. Security sector reform intentions included the abolition of existing police forces and the creation of a new National Civil Police (PNC). The PNC was meant to give substance to a new way of policing in tune with the building of democratic governance and effective law enforcement. This paper examines the general background of the reforms, discusses the limitations of the results so far, and takes a particular and critical look at one of the key components of the police reform: the recruitment and training of PNC aspirants, using the case of the 1999 Fifth Promotion that entered the Academy of the PNC. [source] Hetero-Seeding and Solid Mixture to Obtain New Crystalline FormsCHEMISTRY - A EUROPEAN JOURNAL, Issue 6 2009Dario Braga Prof. Abstract Para -methyl benzyl alcohol (p -MeBA,II) and para -chloro benzyl alcohol (p -ClBA) are quasi-isostructural and share the same hydrogen-bond patterns, but their crystals are not isomorphous. No new polymorphs could be obtained by conventional polymorph screening based on different solvents and different crystallization conditions. Formation of a new polymorph of p -MeBA named p -MeBA,I, isomorphous with the crystal of p -ClBA, was induced by hetero-seeding with a small quantity of powdered p -ClBA added to a supersaturated solution of p -MeBA in hexane, while seeding of p -ClBA with p -MeBA,II failed to give a new phase of p -ClBA isomorphous with known crystalline p -MeBA,II. Mixed crystals of p -MeBA and p -ClBA were also prepared with different p -MeBA/p -ClBA ratios to understand the role of the different functional groups in the crystal structure. Crystal phases were characterized by combined use of single-crystal and powder X-ray diffraction, differential scanning calorimetry, and solid-state NMR spectroscopy. [source] Metastability of Corundum-Type In2O3CHEMISTRY - A EUROPEAN JOURNAL, Issue 11 2008Aleksander Gurlo Dr. Abstract The description of structural relations between bixbyite- and corundum-type structures is of particular interest because of the common occurrence of both structures. One of the representative examples of the bixbyite to corundum transition is the high-pressure high-temperature synthesis of the corundum-type indium oxide. The wet chemistry synthesis and stabilisation of the corundum-type In2O3 under ambient pressure conditions calls for a re-interpretation of the InO phase diagram as well as for the clarification of the phase transitions in In2O3. One of the questions to be clarified is the stability of the corundum-type In2O3. In the present work we studied the stability of the corundum-type In2O3 both theoretically (by density-functional calculations) and experimentally. The synthesis of the corundum-type In2O3 was performed by the modified non-alkoxide sol,gel method based on the ammonia-induced hydrolysis of indium nitrate in methanol. The corundum-type In2O3 was subjected to thermal analysis (STA) as well as to structural studies, that is, it was examined using X-ray powder diffraction (XRPD) including in situ XRPD characterisation upon thermal treatment. For the first time we have undoubtedly demonstrated, both theoretically and experimentally, the metastability of the corundum-type In2O3 polymorph. The In2O3 polymorph appears to be metastable throughout the entire enthalpy,pressure phase diagram. Upon heating, corundum-type In2O3 transforms irreversibly into cubic bixbyite-type In2O3 as shown by STA as well as in situ heating XRPD experiments. Computations indicate the existence of another high-pressure modification of In2O3 with orthorhombic structure, iso-typic to Rh2O3 -II. We predict this new phase to form at pressures exceeding 15,GPa from both the cubic bixbyite-type and the corundum-type modification of In2O3. [source] Investigation of Mechanical and Microstructural Characteristics of Al,Mg Compounds,ADVANCED ENGINEERING MATERIALS, Issue 7 2009Reimund Neugebauer The presented approach of generating composites offers new possibilities for the combination of two light metal alloys into one semifinished product of high specific strength and corrosion resistance. A test device based on the forming method of lateral extrusion was designed to manufacture metallic compounds. The created interface layer is characterized by the formation of new phases and affects the mechanical properties of the whole compound. [source] Study of the Dehydroxylation,Rehydroxylation of PyrophylliteJOURNAL OF THE AMERICAN CERAMIC SOCIETY, Issue 8 2010Jose L. Perez-Rodriguez Pyrophyllite is a raw material of significant interest due to its large number of applications. Most of these applications require a thermal transformation of pyrophyllite; this thermal transformation implies the release of structural OH groups and the formation of new phases. In this paper, we report on the dehydroxylation of pyrophyllite and the reversibility of the process. A value of 224±16 kJ/mol for the dehydroxylation of pyrophyllite was obtained. In addition, it was observed that the partially or totally dehydroxylated pyrophyllite suffered a partial reversible rehydroxylation when cooled to room temperature. This rehydroxylation was substantiated by thermogravimetric measurements, while infrared spectroscopic studies showed that, during the rehydroxylation, the intensity of the OH band at 3675 cm,1 increased as two new bands at 3690 and 3702 cm,1 appeared. This rehydroxylation process was heavily influenced by the particle size of the pyrophyllite. Thus, smaller particles (<1 ,m) showed a larger rehydroxylation percentage (about 12%), while the larger ones (20,40 ,m) showed a smaller percentage (about 1.6%). The extent of rehydroxylation also depended on the dehydroxylation temperature and reached a maximum value at 750°C. [source] Co-Crystallization and Characterization of Pharmaceutical IngredientsPARTICLE & PARTICLE SYSTEMS CHARACTERIZATION, Issue 3 2009Michael Herrmann Abstract Co-crystals may open the door to product tailoring of pharmaceutical products. Selected pharmaceutical ingredients were co-crystallized by mechanical and supercritical methods and the products were characterized by means of X-ray diffraction (XRD) using synchrotron radiation. The experiments revealed sub-micron and nano-structured composite particles, and three new phases, i.e., one cholesterol and two caffeine based. The phase separation and structure resolution of the new phases will form the aims of future investigations. [source] Pressure-induced phase transitions in l -alanine, revisitedACTA CRYSTALLOGRAPHICA SECTION B, Issue 4 2010N. A. Tumanov The effect of pressure on l -alanine has been studied by X-ray powder diffraction (up to 12.3,GPa), single-crystal X-ray diffraction, Raman spectroscopy and optical microscopy (up to ,,6,GPa). No structural phase transitions have been observed. At ,,2,GPa the cell parameters a and b become accidentally equal to each other, but without a change in space-group symmetry. Neither of two transitions reported by others (to a tetragonal phase at ,,2,GPa and to a monoclinic phase at ,,9,GPa) was observed. The changes in cell parameters were continuous up to the highest measured pressures and the cells remained orthorhombic. Some important changes in the intermolecular interactions occur, which also manifest themselves in the Raman spectra. Two new orthorhombic phases could be crystallized from a MeOH/EtOH/H2O pressure-transmitting mixture in the pressure range 0.8,4.7,GPa, but only if the sample was kept at these pressures for at least 1,2,d. The new phases converted back to l -alanine on decompression. Judging from the Raman spectra and cell parameters, the new phases are most probably not l -alanine but its solvates. [source] | |||||||||||||||||||||||||||||||