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Sample records for functional inorganic materials

  1. Crystallization and functionality of inorganic materials

    SciTech Connect

    Xue, Dongfeng; School of Chemical Engineering, Dalian University of Technology, Dalian 116024 ; Li, Keyan; Liu, Jun; Sun, Congting; Chen, Kunfeng; School of Chemical Engineering, Dalian University of Technology, Dalian 116024

    2012-10-15

    In this article, we briefly summarized our recent work on the studies of crystallization and functionality of inorganic materials. On the basis of the chemical bonding theory of single crystal growth, we can quantitatively simulate Cu{sub 2}O crystallization processes in solution system. We also kinetically controlled Cu{sub 2}O crystallization process in the reduction solution route. Lithium ion battery and supercapacitor performances of some oxides such as Co{sub 3}O{sub 4} and MnO{sub 2} were shown to elucidate the important effect of crystallization on functionality of inorganic materials. This work encourages us to create novel functionalities through the study of crystallization of inorganic materials, which warrants more chances in the field of functional materials.

  2. Computationally assisted identification of functional inorganic materials.

    PubMed

    Dyer, Matthew S; Collins, Christopher; Hodgeman, Darren; Chater, Philip A; Demont, Antoine; Romani, Simon; Sayers, Ruth; Thomas, Michael F; Claridge, John B; Darling, George R; Rosseinsky, Matthew J

    2013-05-17

    The design of complex inorganic materials is a challenge because of the diversity of their potential structures. We present a method for the computational identification of materials containing multiple atom types in multiple geometries by ranking candidate structures assembled from extended modules containing chemically realistic atomic environments. Many existing functional materials can be described in this way, and their properties are often determined by the chemistry and electronic structure of their constituent modules. To demonstrate the approach, we isolated the oxide Y(2.24)Ba(2.28)Ca(3.48)Fe(7.44)Cu(0.56)O21, with a largest unit cell dimension of over 60 angstroms and 148 atoms in the unit cell, by using a combination of this method and experimental work and show that it has the properties necessary to function as a solid oxide fuel-cell cathode. PMID:23579498

  3. Biomineralization-inspired synthesis of functional organic/inorganic hybrid materials: organic molecular control of self-organization of hybrids.

    PubMed

    Arakaki, Atsushi; Shimizu, Katsuhiko; Oda, Mayumi; Sakamoto, Takeshi; Nishimura, Tatsuya; Kato, Takashi

    2015-01-28

    Organisms produce various organic/inorganic hybrid materials, which are called biominerals. They form through the self-organization of organic molecules and inorganic elements under ambient conditions. Biominerals often have highly organized and hierarchical structures from nanometer to macroscopic length scales, resulting in their remarkable physical and chemical properties that cannot be obtained by simple accumulation of their organic and inorganic constituents. These observations motivate us to create novel functional materials exhibiting properties superior to conventional materials--both synthetic and natural. Herein, we introduce recent progress in understanding biomineralization processes at the molecular level and the development of organic/inorganic hybrid materials by these processes. We specifically outline fundamental molecular studies on silica, iron oxide, and calcium carbonate biomineralization and describe material synthesis based on these mechanisms. These approaches allow us to design a variety of advanced hybrid materials with desired morphologies, sizes, compositions, and structures through environmentally friendly synthetic routes using functions of organic molecules. PMID:25375353

  4. Geological and Inorganic Materials.

    ERIC Educational Resources Information Center

    Jackson, L. L.; And Others

    1989-01-01

    Presents a review focusing on techniques and their application to the analysis of geological and inorganic materials that offer significant changes to research and routine work. Covers geostandards, spectroscopy, plasmas, microbeam techniques, synchrotron X-ray methods, nuclear activation methods, chromatography, and electroanalytical methods.…

  5. Functionalization of linen/cotton pigment prints using inorganic nano structure materials.

    PubMed

    Ibahim, N A; Eid, B M; Abd El-Aziz, E; Abou Elmaaty, T M

    2013-09-12

    The present work opens up a novel strategy for the development of new multifunctional cellulosic pigment prints. The developed process aims at modifying the solvent-free pigment printing formulations via inclusion of certain inorganic nano materials namely silver (Ag-NPs), zinc oxide (ZnO-NPs), zirconium oxide (ZrO?-NPs) or titanium dioxide (TiO?-NPs) at 20 g/kg paste followed by screen printing and microwave fixation. The imparted functional properties together with the depth of the obtained prints are governed by the type of nano additives, type of binder and the pigment colorant. The imparted antibacterial and/or UV protection properties to the pigment prints were retained with an acceptable level (>70%) of durability even after 20 washing cycles. The presence of nano materials on the surface of the obtained pigment prints was confirmed using SEM images and EDX spectra. PMID:23911482

  6. Inorganic polymer engineering materials

    SciTech Connect

    Stone, M.L.

    1993-06-01

    Phosphazene-based, inorganic-polymer composites have been produced and evaluated as potential engineering materials. The thermal, chemical, and mechanical properties of several different composites made from one polymer formulation have been measured. Measured properties are very good, and the composites show excellent promise for structural applications in harsh environments. Chopped fiberglass, mineral, cellulose, and woodflour filled composites were tested. Chopped fiberglass filled composites showed the best overall properties. The phosphazene composites are very hard and rigid. They have low dielectric constants and typical linear thermal expansion coefficients for polymers. In most cases, the phosphazene materials performed as well or better than analogous, commercially available, filled phenolic composites. After 3 to 5 weeks of exposure, both the phosphazene and phenolics were degraded to aqueous bases and acids. The glass filled phosphazene samples were least affected.

  7. Bridged polysilsesquioxanes: Hybrid organic-inorganic materials as fuel cell polyelectrolyte membranes and functional nanoparticles

    NASA Astrophysics Data System (ADS)

    Khiterer, Mariya

    2007-05-01

    This dissertation describes the design, fabrication, and characterization of organic-inorganic hybrid materials. Several classes of bridged polysilsesquioxanes are presented. The first class is a membrane material suitable for fuel cell technology as a proton conducting polyelectrolyte. The second class includes hybrid nanoparticles for display device applications and chromatographic media. Chapter 1 is an introduction to hybrid organic-inorganic materials. Sol-gel chemistry is discussed, followed by a survey of prominent examples of silica hybrids. Examples of physical organic-silica blends and covalent organo-silicas, including ORMOCERSRTM, polyhedral oligomeric silsesquioxanes, and bridged polysilsesquioxanes are discussed. Bridged polysilsesquioxanes are described in great detail. Monomer synthesis, sol-gel chemistry, processing, characterization, and physical properties are included. Chapter 2 describes the design of polyelectrolyte bridged polysilsesquioxane membranes. The materials contain covalently bound sulfonic acid groups originating from the corresponding disulfides. These organic-inorganic hybrid materials integrate a network supporting component which is systematically changed to fine-tune their physical properties. The membranes are characterized as PEM fuel cell electrolytes, where proton conductivities of 4-6 mS cm-1 were measured. In Chapter 3 techniques for the preparation of bridged polysilsesquioxane nanoparticles are described. An inverse water-in-oil microemulsion polymerization method is developed to prepare cationic nanoparticles, including viologen-bridged materials with applications in electrochromic display devices. An aqueous ammonia system is used to prepare neutral nanoparticles containing hydrocarbon bridging groups, which have potential applications as chromatographic media. Chapter 4 describes electrochromic devices developed in collaboration with the Heflin group of Virginia Tech, which incorporate viologen bridged nanoparticles described in Chapter 3. The devices are prepared via the layer-by-layer deposition technique and characterized by voltammetry and transmission spectroscopy. Contrast ratios between yellow and violet states were 45-50% with switching times of 3-3.5 seconds. Finally, Appendix I describes the resolution of racemic 3,3.3',3'-Tetramethyl-1,1"-spirobisindane-5,5',6,6'-tetrol by diastereomeric complex formation with (8S,9R)-(-)-N-benzylcinchonidinium chloride. Enantiomerically pure bisspirocatechol is used to prepare a chiral polymer, which exhibits differences in solid state packing from polymer made with the racemic monomer. Preliminary results on the use of the chiral polymer in enantioselective membrane separations technology are described.

  8. Hybrid organic-inorganic materials based on poly(o-phenylenediamine) and polyoxometallate functionalized carbon nanotubes

    NASA Astrophysics Data System (ADS)

    Baibarac, M.; Baltog, I.; Smaranda, I.; Scocioreanu, M.; Lefrant, S.

    2011-01-01

    The chemical polymerization of o-phenylenediamine (OPD) on single-walled carbon nanotubes (SWCNTs) in the presence of phosphomolybdic acid (H 3PMo 12O 40xH 2O) has been studied by surface enhanced resonant Raman scattering (SERRS) spectroscopy. One demonstrates that an organic-inorganic hybrid composite of the type poly(o-phenylenediamine)/polyoxometallate-functionalized SWCNTs is produced by the chemical interaction between polyoxometallate-functionalized SWCNTs and poly(o-phenylenediamine) (POPD) doped with [H 2PMo 12O 40] - ions. According to TEM investigations, a result of the chemical interaction of SWCNT with H 3PMo 12O 40xH 2O is the formation into the composite mass of tube fragments of shorter length, which behave like closed shell fullerenes since Raman fingerprint is given by lines situated at 240-275 and 1450-1472 cm -1. The chemical polymerization of OPD on SWCNTs achieved in the absence of H 3PMo 12O 40xH 2O leads to a covalent functionalization of the wall side of the tubes, which is revealed in Raman spectra, recorded at the excitation wavelength of 514 nm, by an enhancement of the lines associated with the tangential vibrational modes of SWCNTs. Using FTIR spectroscopy, significant hindrance steric effects are evidenced in the POPD/polyoxometallate-functionalized SWCNT composite.

  9. Plasma chemistry for inorganic materials

    NASA Technical Reports Server (NTRS)

    Matsumoto, O.

    1980-01-01

    Practical application of plasma chemistry to the development of inorganic materials using both low temperature and warm plasmas are summarized. Topics cover: the surface nitrification and oxidation of metals; chemical vapor deposition; formation of minute oxide particles; the composition of oxides from chloride vapor; the composition of carbides and nitrides; freezing high temperature phases by plasma arc welding and plasma jet; use of plasma in the development of a substitute for petroleum; the production of silicon for use in solar cell batteries; and insulating the inner surface of nuclear fusion reactor walls.

  10. Very Facile Polarity Umpolung and Noncovalent Functionalization of Inorganic Nanoparticles: A Tool Kit for Supramolecular Materials Chemistry.

    PubMed

    Zeininger, Lukas; Petzi, Stefanie; Schönamsgruber, Jörg; Portilla, Luis; Halik, Marcus; Hirsch, Andreas

    2015-09-28

    The facile assembly of shell-by-shell (SbS)-coated nanoparticles [TiO2-PAC16]@shell?1-7 (PAC16 = hexadecylphosphonic acid), which are soluble in water and can be isolated as stable solids, is reported. In these functional architectures, an umpolung of dispersibility (organic apolar versus water) was accomplished by the noncovalent binding of ligands 1-7 to titania nanoparticles [TiO2-PAC16] containing a first covalent coating with PAC16. Ligands 1-7 are amphiphilic and form the outer second shell of [TiO2-PAC16]@shell?1-7. The tailor-designed dendritic building blocks 3-5 contain negative and positive charges in the same molecule, and ligands 6 and 7 contain a perylenetetracarboxylic acid dimide (PDI) core (6/7) as a photoactive reporter component. In the redox and photoactive system [TiO2-PAC16]@shell?7, electronic communication between the inorganic core to the PDI ligands was observed. PMID:26274348

  11. Combinatorial synthesis of inorganic or composite materials

    DOEpatents

    Goldwasser, Isy (Palo Alto, CA); Ross, Debra A. (Mountain Ranch, CA); Schultz, Peter G. (La Jolla, CA); Xiang, Xiao-Dong (Danville, CA); Briceno, Gabriel (Baldwin Park, CA); Sun, Xian-Dong (Fremont, CA); Wang, Kai-An (Cupertino, CA)

    2010-08-03

    Methods and apparatus for the preparation and use of a substrate having an array of diverse materials in predefined regions thereon. A substrate having an array of diverse materials thereon is generally prepared by delivering components of materials to predefined regions on a substrate, and simultaneously reacting the components to form at least two materials or, alternatively, allowing the components to interact to form at least two different materials. Materials which can be prepared using the methods and apparatus of the present invention include, for example, covalent network solids, ionic solids and molecular solids. More particularly, materials which can be prepared using the methods and apparatus of the present invention include, for example, inorganic materials, intermetallic materials, metal alloys, ceramic materials, organic materials, organometallic materials, nonbiological organic polymers, composite materials (e.g., inorganic composites, organic composites, or combinations thereof), etc. Once prepared, these materials can be screened for useful properties including, for example, electrical, thermal, mechanical, morphological, optical, magnetic, chemical, or other properties. Thus, the present invention provides methods for the parallel synthesis and analysis of novel materials having useful properties.

  12. Proceedings of chemical processes in inorganic materials

    SciTech Connect

    Persans, P.D. ); Bradely, J.S.; Chianelli, R.R. ); Schmid, G. )

    1992-01-01

    This book contains proceedings of the Symposium on Chemical Processes in Inorganic Materials: Metal and Semiconductor Clusters and Colloids. Topics covered include: chemical synthesis; particle stabilization; and optical, electronic and catalytic characterization; preparation of metal particles; preparation of semiconductor particles; characterization of metal particles; characterization of semiconductor particles; and stability of clusters and nanoparticles.

  13. Combinatorial screening of inorganic and organometallic materials

    DOEpatents

    Schultz, Peter G. (Oakland, CA); Xiang, Xiaodong (Alameda, CA); Goldwasser, Isy (Alameda, CA)

    2002-01-01

    Methods and apparatus for the preparation and use of a substrate having an array of diverse materials in predefined regions thereon. A substrate having an array of diverse materials thereon is generally prepared by delivering components of materials to predefined regions on a substrate, and simultaneously reacting the components to form at least two materials. Materials which can be prepared using the methods and apparatus of the present invention include, for example, covalent network solids, ionic solids and molecular solids. More particularly, materials which can be prepared using the methods and apparatus of the present invention include, for example, inorganic materials, intermetallic materials, metal alloys, ceramic materials, organic materials, organometallic materials, non-biological organic polymers, composite materials (e.g., inorganic composites, organic composites, or combinations thereof), etc. Once prepared, these materials can be screened for useful properties including, for example, electrical, thermal, mechanical, morphological, optical, magnetic, chemical, or other properties. Thus, the present invention provides methods for the parallel synthesis and analysis of novel materials having useful properties.

  14. Preparation and screening of crystalline inorganic materials

    DOEpatents

    Schultz, Peter G. (La Jolla, CA); Xiang, Xiaodong (Danville, CA); Goldwasser, Isy (Palo Alto, CA); Brice{hacek over (n)}o, Gabriel (Baldwin Park, CA); Sun, Xiao-Dong (Fremont, CA); Wang, Kai-An (Cupertino, CA)

    2008-10-28

    Methods and apparatus for the preparation and use of a substrate having an array of diverse materials in predefined regions thereon. A substrate having an array of diverse materials thereon is generally prepared by delivering components of materials to predefined regions on a substrate, and simultaneously reacting the components to form at least two materials. Materials which can be prepared using the methods and apparatus of the present invention include, for example, covalent network solids, ionic solids and molecular solids. More particularly, materials which can be prepared using the methods and apparatus of the present invention include, for example, inorganic materials, intermetallic materials, metal alloys, ceramic materials, organic materials, organometallic materials, non-biological organic polymers, composite materials (e.g., inorganic composites, organic composites, or combinations thereof), etc. Once prepared, these materials can be screened for useful properties including, for example, electrical, thermal, mechanical, morphological, optical, magnetic, chemical, or other properties. Thus, the present invention provides methods for the parallel synthesis and analysis of novel materials having useful properties.

  15. Studies of mesoporous inorganic materials

    NASA Astrophysics Data System (ADS)

    Khushalani, Deepa

    Studies in synthesis and characterization of mesoporous silica have been performed. In particular, four aspects have been studied. Primarily, a new synthetic route to enlarge the porosity of mesoporous silica materials has been developed. The synthetic strategy involves aging the syntheses mixture in the mother liquor and depending on the aging time, a gradual increase in pore sizes is observed from 40 to 65 A. The growth process involves restructuring of the mesopores under mild aqueous conditions without changing the length of the alkyl chain of the surfactant or addition of auxiliary hydrocarbon molecules. The pore-enlarged products retain the crystal morphology of the starting materials and appreciable solubilization of the structure is not observed during the aging process. Templating behavior of cetylpyridinium chloride in the synthesis of mesoporous silica has also been evaluated. Noticeable improvement in the quality of the resulting product is observed through PXRD, TEM, and adsorption analyses. Synthesis of mesoporous silica is also demonstrated using templating behavior of a mixture of two surfactants: cetylpyridinium chloride (CPCl) and cetyltrimethylammonium chloride (CTACl). As the CPCl :CTACl molar ratio is decreased, a gradual increase in the d100-spacing is observed starting at ca. 41 A and in sub-angstrom increments reaching to that of ca. 43 A. A model is presented that simultaneously accounts for the higher degree of structural order of the mesoporous silica templated with CPCl and the ability to fine tune d-spacings on a sub-angstrom length scale using CPCl/CTACl mixtures. In addition, a novel non-aqueous route to formation of lamellar and hexagonal phase of mesoporous silica has been developed. Ethylene glycol is employed as a solvent and as a chelating agent. The chelate effect results in stable glycosilicate(IV) complexes which are necessary for the syntheses and the framework thermal stability of the products has been found to increase via chemical vapor deposition of disilane. This synthetic route has been extended to the synthesis of a novel mesostructured titanium oxide and mixed mesostructured titanium/silicon oxides. The mesoporous mixed titanium/silicon oxides are envisaged to have diverse applications in catalysis, large molecule adsorption and separation science, and the synthetic route developed provides the potential for synthesis of other mesoporous mixed metal oxides over a wide range of compositions.

  16. Inorganic polymers and materials. Final report

    SciTech Connect

    Sneddon, Larry G.

    2001-01-01

    This DOE-sponsored project was focused on the design, synthesis, characterization, and applications of new types of boron and silicon polymers with a goal of attaining processable precursors to advanced ceramic materials of technological importance. This work demonstrated a viable design strategy for the systematic formation of polymeric precursors to ceramics based on the controlled functionalization of preformed polymers with pendant groups of suitable compositions and crosslinking properties. Both the new dipentylamine-polyborazylene and pinacolborane-hydridopolysilazane polymers, unlike the parent polyborazylene and other polyborosilazanes, are stable as melts and can be easily spun into polymer fibers. Subsequent pyrolyses of these polymer fibers then provide excellent routes to BN and SiNCB ceramic fibers. The ease of synthesis of both polymer systems suggests new hybrid polymers with a range of substituents appended to polyborazylene or polysilazane backbones, as well as other types of preceramic polymers, should now be readily achieved, thereby allowing even greater control over polymer and ceramic properties. This control should now enable the systematic tailoring of the polymers and derived ceramics for use in different technological applications. Other major recent achievements include the development of new types of metal-catalyzed methods needed for the polymerization and modification of inorganic monomers and polymers, and the modification studies of polyvinylsiloxane and related polymers with substituents that enable the formation of single source precursors to high-strength, sintered SiC ceramics.

  17. Utilization of specific and non-specific peptide interactions with inorganic nanomaterials on the surface of bacteriophage M13: Methodologies towards phage supported bi-functional materials

    NASA Astrophysics Data System (ADS)

    Avery, Kendra Nicole

    Many types of organisms create a variety of nano and micro scale materials from precursors available in their surrounding environments by a process called biomineralization. As scientists begin to understand how these organisms utilize specific and non-specific interactions with a variety of biopolymers such as chitin, peptides, proteins and nucleic acids with these precursors to create inorganic/organic composite materials, they have begun to wonder about the synthesis of other types of non-biologically templated synthetic techniques that might be possible. Bioengineered organisms and biopolymers have begun to be used for these types of studies. A variety of selection techniques exist for discovering biopolymers with an affinity for a target material, however, one of the most notable is a technique called peptide phage display. This is a technique that utilizes a commercially available randomized peptide library attached at the tip of the filamentous bacteriophage M13. In this dissertation capabilities of bacteriophage M13 are explored in regard to the creation of bi-functional nano materials by exploiting both specific peptide interactions as well as non-specific peptide interactions on the surface of the organism. Chapter 2 focuses on utilizing the specific peptide interactions of the randomized library at pIII in order to discover peptides with high binding affinity for a variety of nanomaterials. Selection studies called biopanning are performed on a variety of nanomaterials such as CaMoO4, allotropes of Ni, Fe2O3 and Fe3O4, and Rh and Pt with the fcc type crystal structure. Similarities and differences between peptides discovered for these materials are discussed. Chapter 3 focuses on utilizing the non-specific peptide interactions on the long axis of M13 called pVIII. The pVIII region consists of 2700 copies of the same 50 amino acid protein which as a negatively charged domain which is exposed to solution. The pVIII region therefore provides the surface of the phage with a negative charge on which nanomaterials can be supported. Metal salt precursors reduced in the presence of WT M13 are studied in this chapter. Metal salt precursors of Fe, Co, Ru, Rh and Pd seem to be the most effective at coating the surface of the phage based on the positively charged metal-aquo complexes formed in water, which are attracted to the negative pVIII region. Other types of reactions are explored with WT phage as a scaffold such as conversion chemistry in a polyol solvent to access several intermetallic phases as well as co-precipitation reactions to access ternary oxides. Chapter 4 focuses on combining research from chapter 2 and chapter 3 to create a bi-functional material that utilizes both specific and non-specific peptide interactions with inorganic materials on the surface of M13 to attach two different types of nanomaterials. The example provided here is a magnetically recoverable hydrogenation catalyst made up of a pVIII region coated with rhodium nanoparticles held in place by non-specific peptide interactions and a pIII region attached to iron oxide nanoparticles via specific peptide interactions. This is the first example in the literature of a commercially available pIII bioengineered M13 bacteriophage forming a bi-functional material. This research provides a methodology to design and build single and multi-component materials on the surface of bacteriophage M13 without the necessity for additional bioengineering and library characterization. The simplicity of use will make the technique available to a wider variety of researchers in the materials science community.

  18. Rational design of inorganic dielectric materials with expected permittivity

    PubMed Central

    Xie, Congwei; Oganov, Artem R.; Dong, Dong; Liu, Ning; Li, Duan; Debela, Tekalign Terfa

    2015-01-01

    Techniques for rapid design of dielectric materials with appropriate permittivity for many important technological applications are urgently needed. It is found that functional structure blocks (FSBs) are helpful in rational design of inorganic dielectrics with expected permittivity. To achieve this, coordination polyhedra are parameterized as FSBs and a simple empirical model to evaluate permittivity based on these FSB parameters is proposed. Using this model, a wide range of examples including ferroelectric, high/low permittivity materials are discussed, resulting in several candidate materials for experimental follow-up. PMID:26617342

  19. Organic materials as templates for the formation of mesoporous inorganic materials and ordered inorganic nanocomposites

    NASA Astrophysics Data System (ADS)

    Ziegler, Christopher R.

    Hierarchically structured inorganic materials are everywhere in nature. From unicellular aquatic algae such as diatoms to the bones and/or cartilage that comprise the skeletal systems of vertebrates. Complex mechanisms involving site-specific chemistries and precision kinetics are responsible for the formation of such structures. In the synthetic realm, reproduction of even the most basic hierarchical structure effortlessly produced in nature is difficult. However, through the utilization of self-assembling structures or "templates", such as polymers or amphiphilic surfactants, combined with some favorable interaction between a chosen inorganic, the potential exists to imprint an inorganic material with a morphology dictated via synthetic molecular self-assembly. In doing so, a very basic hierarchical structure is formed on the angstrom and nanometer scales. The work presented herein utilizes the self-assembly of either surfactants or block copolymers with the desired inorganic or inorganic precursor to form templated inorganic structures. Specifically, mesoporous silica spheres and copolymer directed calcium phosphate-polymer composites were formed through the co-assembly of an organic template and a precursor to form the desired mesostructured inorganic. For the case of the mesoporous silica spheres, a silica precursor was mixed with cetyltrimethylammonium bromide and cysteamine, a highly effective biomimetic catalyst for the conversion of alkoxysilanes to silica. Through charge-based interactions between anionic silica species and the micelle-forming cationic surfactant, ordered silica structures resulted. The incorporation of a novel, effective catalyst was found to form highly condensed silica spheres for potential application as catalyst supports or an encapsulation media. Ordered calcium phosphate-polymer composites were formed using two routes. Both routes take advantage of hydrogen bonding and ionic interactions between the calcium and phosphate precursors and the self-assembling copolymer template. Some evidence suggests that the copolymer morphology remained in the composite despite the known tendency for calcium phosphates to form highly elongated crystalline structures with time, as is commonly the case for synthetic hydroxyapatites. Such materials have obvious application as bone grafts and bone coatings due, in part, to the osteoconductive nature of calcium phosphate as well as to the mesoporosity generated through the cooperative assembly of the block copolymer and the inorganic. Future work, including potential experiments to determine osteoconductivity of as-prepared composites, is also presented herein.

  20. Strongly coupled inorganic/nanocarbon hybrid materials for advanced electrocatalysis.

    PubMed

    Liang, Yongye; Li, Yanguang; Wang, Hailiang; Dai, Hongjie

    2013-02-13

    Electrochemical systems, such as fuel cell and water splitting devices, represent some of the most efficient and environmentally friendly technologies for energy conversion and storage. Electrocatalysts play key roles in the chemical processes but often limit the performance of the entire systems due to insufficient activity, lifetime, or high cost. It has been a long-standing challenge to develop efficient and durable electrocatalysts at low cost. In this Perspective, we present our recent efforts in developing strongly coupled inorganic/nanocarbon hybrid materials to improve the electrocatalytic activities and stability of inorganic metal oxides, hydroxides, sulfides, and metal-nitrogen complexes. The hybrid materials are synthesized by direct nucleation, growth, and anchoring of inorganic nanomaterials on the functional groups of oxidized nanocarbon substrates including graphene and carbon nanotubes. This approach affords strong chemical attachment and electrical coupling between the electrocatalytic nanoparticles and nanocarbon, leading to nonprecious metal-based electrocatalysts with improved activity and durability for the oxygen reduction reaction for fuel cells and chlor-alkali catalysis, oxygen evolution reaction, and hydrogen evolution reaction. X-ray absorption near-edge structure and scanning transmission electron microscopy are employed to characterize the hybrids materials and reveal the coupling effects between inorganic nanomaterials and nanocarbon substrates. Z-contrast imaging and electron energy loss spectroscopy at single atom level are performed to investigate the nature of catalytic sites on ultrathin graphene sheets. Nanocarbon-based hybrid materials may present new opportunities for the development of electrocatalysts meeting the requirements of activity, durability, and cost for large-scale electrochemical applications. PMID:23339685

  1. Engineering the Interface Between Inorganic Materials and Cells

    SciTech Connect

    Schaffer, David

    2014-05-31

    To further optimize cell function in hybrid “living materials”, it would be advantageous to render mammalian cells responsive to novel “orthogonal” cues, i.e. signals they would not ordinarily respond to but that can be engineered to feed into defined intracellular signaling pathways. We recently developed an optogenetic method, based on A. thaliana Cry2, for rapid and reversible protein oligomerization in response to blue light. We also demonstrated the ability to use this method to channel the light input into several defined signaling pathways, work that will enhance communication between inorganic devices and living systems.

  2. Casting fine grained, fully dense, strong inorganic materials

    DOEpatents

    Brown, Sam W.; Spencer, Larry S.; Phillips, Michael R.

    2015-11-24

    Methods and apparatuses for casting inorganic materials are provided. The inorganic materials include metals, metal alloys, metal hydrides and other materials. Thermal control zones may be established to control the propagation of a freeze front through the casting. Agitation from a mechanical blade or ultrasonic energy may be used to reduce porosity and shrinkage in the casting. After solidification of the casting, the casting apparatus may be used to anneal the cast part.

  3. Strongly coupled inorganic-nano-carbon hybrid materials for energy storage.

    PubMed

    Wang, Hailiang; Dai, Hongjie

    2013-04-01

    The global shift of energy production from fossil fuels to renewable energy sources requires more efficient and reliable electrochemical energy storage devices. In particular, the development of electric or hydrogen powered vehicles calls for much-higher-performance batteries, supercapacitors and fuel cells than are currently available. In this review, we present an approach to synthesize electrochemical energy storage materials to form strongly coupled hybrids (SC-hybrids) of inorganic nanomaterials and novel graphitic nano-carbon materials such as carbon nanotubes and graphene, through nucleation and growth of nanoparticles at the functional groups of oxidized graphitic nano-carbon. We show that the inorganic-nano-carbon hybrid materials represent a new approach to synthesize electrode materials with higher electrochemical performance than traditional counterparts made by simple physical mixtures of electrochemically active inorganic particles and conducting carbon materials. The inorganic-nano-carbon hybrid materials are novel due to possible chemical bonding between inorganic nanoparticles and oxidized carbon, affording enhanced charge transport and increased rate capability of electrochemical materials without sacrificing specific capacity. Nano-carbon with various degrees of oxidation provides a novel substrate for nanoparticle nucleation and growth. The interactions between inorganic precursors and oxidized-carbon substrates provide a degree of control over the morphology, size and structure of the resulting inorganic nanoparticles. This paper reviews the recent development of inorganic-nano-carbon hybrid materials for electrochemical energy storage and conversion, including the preparation and functionalization of graphene sheets and carbon nanotubes to impart oxygen containing groups and defects, and methods of synthesis of nanoparticles of various morphologies on oxidized graphene and carbon nanotubes. We then review the applications of the SC-hybrid materials for high performance lithium ion batteries, rechargeable Li-S and Li-O2 batteries, supercapacitors and ultrafast Ni-Fe batteries, and new electrocatalysts for oxygen reduction, oxygen evolution and hydrogen evolution reactions. PMID:23361617

  4. Functionalization of inorganic nanoparticles for bioimaging applications.

    PubMed

    Erathodiyil, Nandanan; Ying, Jackie Y

    2011-10-18

    Modern biomedical imaging technologies have led to significant advances in diagnosis and therapy. Because most disease processes occur at the molecular and cellular levels, researchers continue to face challenges in viewing and understanding these processes precisely and in real time. The ideal imaging resolution would be in nanometers, because most biological processes take place on this length scale. Therefore, the functionalization of nanoparticles (NPs) and their use in therapeutic and diagnostic applications are of great interest. Molecular and cellular imaging agents made from inorganic NPs have been developed to probe such biological events noninvasively. The conjugation of tiny NPs with specific biomolecules allows researchers to target the desired location, reduce overall toxicity, and boost the efficiency of the imaging probes. In this Account, we review recent research on the functionalization of NPs for bioimaging applications. Several types of NPs have been employed for bioimaging applications, including metal (Au, Ag), metal oxide (Fe(3)O(4)), and semiconductor nanocrystals (e.g. quantum dots (QDs) and magnetic quantum dots (MQDs)). The preparation of NPs for bioimaging applications can include a variety of steps: synthesis, coating, surface functionalization, and bioconjugation. The most common strategies of engineering NP surfaces involve physical adsorption or chemisorption of the desired ligands onto the surface. Chemisorption or covalent linkages are preferred, and the coated NPs should possess high colloidal stability, biocompatibility, water solubility, and functional groups for further bioconjugation. Many of the functionalization techniques that have been reported in the literature suffer from limitations such as complex synthesis steps, poor biocompatibility, low stability, and hydrophobic products. Coating strategies based on chemisorption and ligand exchange often provide a better way to tailor the surface properties of NPs. After conjugation with the appropriate targeting ligands, antibodies, or proteins, the NPs may exhibit highly selective binding, making them useful for fluorescence imaging, magnetic resonance imaging (MRI), positron emission tomography (PET) imaging, and multimodal imaging. PMID:21648430

  5. Investigation of novel inorganic resist materials for EUV lithography

    NASA Astrophysics Data System (ADS)

    Krysak, Marie E.; Blackwell, James M.; Putna, Steve E.; Leeson, Michael J.; Younkin, Todd R.; Harlson, Shane; Frasure, Kent; Gstrein, Florian

    2014-04-01

    Recently, both PSI1 and ASML2 illustrated champion EUVL resolution using slow, non-chemically amplified inorganic resists. However, the requirements for EUVL manufacturing require simultaneous delivery of high resolution, good sensitivity, and low line edge/width roughness (LER/LWR) on commercial grade hardware. As a result, we believe that new classes of materials should be explored and understood. This paper focuses on our efforts to assess metal oxide based nanoparticles as novel EUV resists3. Various spectroscopic techniques were used to probe the patterning mechanism of these materials. EUV exposure data is presented to investigate the feasibility of employing inorganic materials as viable EUV resists.

  6. Nanoelectromechanics of Inorganic and Biological Systems: From Structural Imaging to Local Functionalities

    SciTech Connect

    Rodriguez, Brian; Kalinin, Sergei V; Jesse, Stephen; Thompson, G. L.; Vertegel, Alexey; Hohlbauch, Sophia; Proksch, Roger

    2008-01-01

    Coupling between electrical and mechanical phenomena is extremely common in inorganic materials, and nearly ubiquitous in biological systems, underpinning phenomena and devices ranging from SONAR to cardiac activity and hearing. This paper briefly summarizes the Scanning Probe Microscopy (SPM) approach, referred to as Piezoresponse Force Microscopy (PFM), for probing electromechanical coupling on the nanometer scales, and delineates some existing and emerging applications to probe local structure and functionality in inorganic ferroelectrics, calcified and connective tissues, and complex biosystems based on electromechanical detection.

  7. Oxide materials for electronics Inorganic Materials and Ceramics Research Group

    E-print Network

    ) · ~ 70 Ph.D. students · ~ 15 post doc./researchers · 4 "sections" at the DMSE: · Physical metallurgy · Process metallurgy · Electrochemistry · Inorganic chemistry · 15 PhD and ~60 MSc students graduating

  8. Inorganic Photovoltaics Materials and Devices: Past, Present, and Future

    NASA Technical Reports Server (NTRS)

    Hepp, Aloysius F.; Bailey, Sheila G.; Rafaelle, Ryne P.

    2005-01-01

    This report describes recent aspects of advanced inorganic materials for photovoltaics or solar cell applications. Specific materials examined will be high-efficiency silicon, gallium arsenide and related materials, and thin-film materials, particularly amorphous silicon and (polycrystalline) copper indium selenide. Some of the advanced concepts discussed include multi-junction III-V (and thin-film) devices, utilization of nanotechnology, specifically quantum dots, low-temperature chemical processing, polymer substrates for lightweight and low-cost solar arrays, concentrator cells, and integrated power devices. While many of these technologies will eventually be used for utility and consumer applications, their genesis can be traced back to challenging problems related to power generation for aerospace and defense. Because this overview of inorganic materials is included in a monogram focused on organic photovoltaics, fundamental issues and metrics common to all solar cell devices (and arrays) will be addressed.

  9. Thermal/chemical degradation of inorganic membrane materials

    SciTech Connect

    Krishnan, G.N.; Damle, A.S.; Sanjurjo, A.; Wood, B.J.; Lau, K.H.

    1995-12-01

    The objective of this program is to evaluate the long-term thermal and chemical degradation of inorganic membranes that are developed to separate gases produced by coal combustion and coal gasification. Membrane materials tested include alumina, vycor, platinum foil, and palladium foils. The porosity, permeability, and characterization of physical and chemical changes after exposure to hot gas streams is described.

  10. STABILITY AND TRANSPORT OF INORGANIC COLLOIDS THROUGH CONTAMINATED AQUIFER MATERIAL

    EPA Science Inventory

    Laboratory columns using contaminated natural aquifer material from Globe, Arizona, were used to investigate the transport of inorganic colloids under saturated flow conditions. e2O3 radio-labeled spherical colloids of various diameters were synthesized and introduced into the co...

  11. Screening combinatorial arrays of inorganic materials with spectroscopy or microscopy

    DOEpatents

    Schultz, Peter G.; Xiang, Xiaodong; Goldwasser, Isy

    2004-02-03

    Methods and apparatus for the preparation and use of a substrate having an array of diverse materials in predefined regions thereon. A substrate having an array of diverse materials thereon is generally prepared by delivering components of materials to predefined regions on a substrate, and simultaneously reacting the components to form at least two materials. Materials which can be prepared using the methods and apparatus of the present invention include, for example, covalent network solids, ionic solids and molecular solids. More particularly, materials which can be prepared using the methods and apparatus of the present invention include, for example, inorganic materials, intermetallic materials, metal alloys, ceramic materials, organic materials, organometallic materials, non-biological organic polymers, composite materials (e.g., inorganic composites, organic composites, or combinations thereof), etc. Once prepared, these materials can be screened for useful properties including, for example, electrical, thermal, mechanical, morphological, optical, magnetic, chemical, or other properties. Thus, the present invention provides methods for the parallel synthesis and analysis of novel materials having useful properties.

  12. Thermochromic materials and devices: Inorganic systems

    SciTech Connect

    Jorgenson, G.V.; Lee, J.C.

    1990-12-31

    This chapter discusses the technological application of a class of materials with a chameleon-like nature, that is, they exhibit the properties of metals under certain conditions of temperature and pressure, and semiconductor-to-dielectric properties under other conditions. Many materials exhibit this behavior, most notably the transition metal oxides and sulfides. Typically, the transition from one state to another in transition metal oxides is accompanied by a sharp change in electrical conductivity (as large as 10{sup 7} in some oxides of vanadium), as well as changes in other physical properties such as crystalline symmetry. The changes in electrical conductivity alter, in turn, IR transmittance, and some of these effects extend into the visible spectrum. A material such as this, whose transition occurs at the appropriate temperature, would be useful for solar energy control in buildings. For example, a coating of thermochromic (TC) material on glass would transmit solar energy at temperatures below its transition temperature (T{sub t}), and when the temperature rises above T{sub t}, the TC material would reflect the incident solar energy. Thus, solar influx would be high at low ambient temperature and low at high temperature. Though very few of these materials have T{sub t} in the range required for such an application, one can adjust T{sub t} by using dopants. Many models have been developed to explain the transition mechanism in TC materials, especially in the vanadium oxides, and the authors review some of these theories here. They also discuss thermochromism in stoichiometric compounds and in doped compounds and present the results of a program to dope VO{sub 2} for a solar control glazing applications. Tungsten-doped VO{sub 2} thin films with useful T{sub t} ({approx} 10 to 18 C) were routinely deposited on glass substrates. The chapter closes with a discussion of the performance of these films and their commercial applicability.

  13. Inorganic photochromic and cathodochromic recording materials.

    NASA Technical Reports Server (NTRS)

    Duncan, R. C., Jr.; Faughnan, B. W.; Phillips, W.

    1971-01-01

    Discussion of studies at RCA Laboratories of the properties of rare-earth-doped CaF2, transition-metal-doped SrTiO3 and iron- or sulfur-doped sodalite as photochromic materials which change color during light or electron beam exposures. Particular attention is given to their photochromic characteristics in single-crystal and powder forms and to their cathodochromic properties in powder form. Details are given on the photochromic mechanisms, spectra, optical density, thermal decay rates, and coloring and bleaching efficiency of their single crystals and on the diffuse reflectance spectra, saturated photochromic contrast ratio, switching and erase sensitivities, and cathodochromic excitation of their photochromic powders. The many attractive characteristics of these materials when used in display storage systems are indicated.

  14. Bioinspired, functional nanoscale materials

    NASA Astrophysics Data System (ADS)

    Jun, In-Kook

    Functional nanomaterials in nature exhibit many unique functions and optical and mechanical properties. Examples of this include the dry adhesion of a gecko's foot, the reduced drag on a shark's skin, the high strength and toughness of nacre, and the superhydrophobic self-cleaning of a lotus leaf. This dissertation is devoted to creating unique and enhanced properties by mimicking such functional materials. We have developed a novel self-pumping membrane, which does not require an applied voltage. The self-pumping membrane harvests chemical energy from a surrounding fluid and uses it for accelerated mass transport across the membrane. A device such as this has promising applications in implantable or remotely operating autonomous devices and membrane-based purification systems. Reproducible and highly active surface enhanced Raman scattering (SERS) substrates were developed using a bottom-up self-assembly technology. With their high sensitivity and good reproducibility, the developed nanostructures (gold nanoparticle and nanohole arrays) as SERS substrates are very promising for applications such as ultra-sensitive detectors for chemicals and reproducible sensors for chemical and biological molecules. Binary colloidal crystals were created using a simple, fast, and scalable spin-coating technology. Although further investigation of the procedure is needed to improve the ordering of particles in the individual layers, the developed assembly technology has a promising outlook in applications such as optical integrated circuits and high-speed optical computing. Inorganic-organic nanocomposites were realized by assembling synthesized gibbsite nanoplatelets using the electrophoretic deposition and infiltration of a monomer followed by polymerization. Via surface modifications of gibbsite nanoplatelets, nanocomposites were further reinforced with covalent linkages between the inorganic platelets and organic matrix.

  15. Combinatorial Screening Of Inorganic And Organometallic Materials

    SciTech Connect

    Li, Yi , Li, Jing , Britton, Ted W.

    2002-06-25

    A method for differentiating and enumerating nucleated red blood cells in a blood sample is described. The method includes the steps of lysing red blood cells of a blood sample with a lytic reagent, measuring nucleated blood cells by DC impedance measurement in a non-focused flow aperture, differentiating nucleated red blood cells from other cell types, and reporting nucleated red blood cells in the blood sample. The method further includes subtracting nucleated red blood cells and other interference materials from the count of remaining blood cells, and reporting a corrected white blood cell count of the blood sample. Additionally, the method further includes measuring spectrophotometric absorbance of the sample mixture at a predetermined wavelength of a hemoglobin chromogen formed upon lysing the blood sample, and reporting hemoglobin concentration of the blood sample.

  16. Reference Materials for Fluorescence Based on Inorganic Glass

    NASA Astrophysics Data System (ADS)

    Levin, A. D.; Pribytkov, V. A.; Nagaev, A. I.; Sadagov, A. Yu.

    Reference materials (RM) for relative spectral correction of emission spectra and day-to-day sensitivity monitoring of spectrofluorimeters were developed. The 2 kinds of inorganic glass were used as RM material - custom developed Cu+ -ion doped phosphate glass and colored optical glass SZS-17 (blue-green). RM can be either cuvette-shaped or in the form of flat plate and installed in sample compartment of the instrument. Flat plate geometry allows to minimize the dependency of RM fluorescence intensity from the characteristics of instrument's optical circuit due to inner filter effect.

  17. Interactions between lipid bilayers and inorganic material surfaces

    NASA Astrophysics Data System (ADS)

    Mager, Morgan Douglas

    Because of their unique biological and material properties, lipid bilayers have been extensively studied for use in biosensor and drug delivery applications. In the past, these systems have mostly taken the form of bulk solutions. More recently, researchers have integrated bilayers with chip-based architectures to take advantage of advanced optical, scanning probe and electronic characterization. These applications typically involve the creation of hybrid devices with inorganic and bilayer components, both of which affect the final device performance. In particular, the properties of supported lipid bilayers (SLBs) are known to depend on the substrate chemistry and topography as well as the lipid used. In spite of the large body of work involving these systems, there is still much that remains unknown about the formation and ultimate structure of the interface between these very different materials. One outstanding question in the study of SLBs is the role that the bilayer deposition method plays in determining the bilayer properties. In this work, we have developed a new method for forming and patterning lipid bilayers: bubble collapse deposition (BCD). This method is similar to an in situ version of Langmuir-Blodgett deposition, and offers unique possibilities for the fabrication of lipid-based devices. Briefly, a lipid monolayer is "inked" onto the surface of an air bubble. This bubble is then brought down on a solid support and the air is withdrawn. This withdrawal of air shrinks the bubble, which causes the monolayer to fold over on itself and redeposit on the surface as a bilayer. With BCD, we have demonstrated the first SLB formation on alumina using uncharged lipids. Using this system, we have measured a previously unobserved enhanced hydrodynamic coupling at the alumina surface. We have also used BCD to produce a hybrid lipid-gated chemical delivery device with potentially sub-cellular spatial resolution. Because of the unique material properties of the lipid seals in this system, these devices can retain a chemical of interest for weeks and yet rapidly release this load (within tens of ms) when triggered by a simple optical input. Finally, we have used BCD to directly transfer lipids from a cell membrane to a substrate surface. We present studies characterizing which membrane components are transferred, including lipids, proteins and the cytoskeleton. These studies offer both increased functionality of hybrid lipid systems and fundamental insights into the interactions between lipids and common semiconductor fabrication materials.

  18. Functionalized inorganic membranes for gas separation

    DOEpatents

    Ku, Anthony Yu-Chung (Rexford, NY); Ruud, James Anthony (Delmar, NY); Molaison, Jennifer Lynn (Marietta, GA); Schick, Louis Andrew ,(Delmar, NY); Ramaswamy, Vidya (Niskayuna, NY)

    2008-07-08

    A porous membrane for separation of carbon dioxide from a fluid stream at a temperature higher than about 200.degree. C. with selectivity higher than Knudsen diffusion selectivity. The porous membrane comprises a porous support layer comprising alumina, silica, zirconia or stabilized zirconia; a porous separation layer comprising alumina, silica, zirconia or stabilized zirconia, and a functional layer comprising a ceramic oxide contactable with the fluid stream to preferentially transport carbon dioxide. In particular, the functional layer may be MgO, CaO, SrO, BaO, La.sub.2O.sub.3, CeO.sub.2, ATiO.sub.3, AZrO.sub.3, AAl.sub.2O.sub.4, A.sup.1FeO.sub.3, A.sup.1MnO.sub.3, A.sup.1CoO.sub.3, A.sup.1NiO.sub.3, A.sup.2HfO.sub.3, A.sup.3CeO.sub.3, Li.sub.2ZrO.sub.3, Li.sub.2SiO.sub.3, Li.sub.2TiO.sub.3 or a mixture thereof; wherein A is Mg, Ca, Sr or Ba; A.sup.1 is La, Ca, Sr or Ba; A.sup.2 is Ca, Sr or Ba; and A.sup.3 is Sr or Ba.

  19. Novel inorganic materials for polymer electrolyte and alkaline fuel cells

    NASA Astrophysics Data System (ADS)

    Tadanaga, Kiyoharu

    2012-06-01

    Inorganic materials with high ionic conductivity must have big advantages for the thermal and long term stability when the materials are used as the electrolyte of fuel cells. In the present paper, novel ionic conductive inorganic materials for polymer electrolyte fuel cells (PEFCs) and all solid state alkaline fuel cells (AFCs) that have been developed by our group have been reviewed. PEFCs which can operate in temperature range from 100 to 200 °C are intensively studied because of some advantages such as reduction of CO poisoning of Pt catalyst and acceleration of electrode reactions. We showed that the fuel cells using the composite membranes prepared from phosphosilicate gel powder and polyimide precursor can operate in the temperature range from 30 to 180 °C. We also found that the inorganic-organic hybrid membranes with acid-base pairs from 3-aminopropyl triethoxy silane and H2SO4 or H3PO4 show high proton conductivity under dry atmosphere, and the membranes are thermally stable at intermediate temperatures. On the other hand, because the use of noble platinum is the serious problem for the commercialization of PEFCs and because oxidation reactions are usually faster than those of acid-type fuel cells, alkaline type fuel cells, in which a nonplatinum catalyst can be used, are attractive. Recently, we have proposed an alkaline-type direct ethanol fuel cell (DEFC) using a natural clay electrolyte with non-platinum catalysts. So-called hydrotalcite clay, Mg-Al layered double hydroxide intercalated with CO32- (Mg-Al CO32- LDH), has been proved to be a hydroxide ion conductor. An alkalinetype DEFC using Mg-Al CO32- LDH as the electrolyte and aqueous solution of ethanol and potassium hydroxide as a source of fuel exhibited excellent electrochemical performance.

  20. Inorganic polarization devices with optical functional layers fabricated by glancing angle deposition technique

    NASA Astrophysics Data System (ADS)

    Takada, Akio; Koike, Nobuyuki; Takahashi, Eiji

    2015-08-01

    The inorganic polarization devices for visible range, namely the absorptive gird polarizers and form birefringent wave plates, were developed. These devices are composed only of inorganic materials and glancing angle deposition technique was employed to fabricate their optical functional layers, which are the absorptive layer and columnar birefringent structure for the polarizers and wave plates, respectively. The optical performance and reliability of these devices were experimentally evaluated and showed them to be suitable for applications requiring high light resistance and thermal durability, such as liquid crystal display projectors.

  1. Attenuation contrast between biomolecular and inorganic materials at terahertz frequencies

    NASA Astrophysics Data System (ADS)

    Chan, T. L. J.; Bjarnason, J. E.; Lee, A. W. M.; Celis, M. A.; Brown, E. R.

    2004-09-01

    Wideband photomixing spectroscopy is used in the present work to contrast the transmission spectra of macromolecules commonly found in biomaterials such as potato starch, wheat flour and cornstarch, and proteins (Cytoplex™), and micromolecules such as sucrose, and inorganic materials such as sodium bicarbonate, and calcium sulfate. Powdered samples were measured at 0.1-0.5THz frequencies. A significant difference in attenuation is found between these samples. At 300GHz starch shows an absorption coefficient of ˜6cm-1 whereas Cytoplex shows 1-3cm-1, while inorganic micromolecules have ˜1cm-1. The absorption in starch increases rapidly with frequency tending to follow a power law ? =fn with n typically between 1.5 and 2.0. In contrast, protein materials display a slower dependence on frequency with n between 1.0 and 1.5, and simple molecules show the least n among all three categories. The difference between these ubiquitous macromolecular and micromolecular materials is explained in terms of water content and molecular structure.

  2. Universal dispersing agent for electrophoretic deposition of inorganic materials with improved adsorption, triggered by chelating monomers.

    PubMed

    Liu, Yangshuai; Luo, Dan; Ata, Mustafa S; Zhang, Tianshi; Wallar, Cameron J; Zhitomirsky, Igor

    2016-01-15

    Poly[1-[4-(3-carboxy-4-hydroxyphenylazo)benzenesulfonamido]-1,2-ethanediyl, sodium salt] (PAZO) is a polymeric functional material with a number of unique physical properties, which attracted significant interest of different scientific communities. Films of PAZO were deposited by anodic electrophoretic deposition (EPD) under constant current and constant voltage conditions. The deposition kinetics was analyzed under different conditions and the deposition mechanism was discussed. New strategy was developed for the EPD of different inorganic materials and composites using PAZO as a dispersing, charging, binding and film forming agent. It was found that PAZO exhibits remarkable adsorption on various inorganic materials due to the presence of chelating salicylate ligands in its molecular structure. The salicylate ligands of PAZO monomers provide multiple adsorption sites by complexation of metal atoms on particle surfaces and allow for efficient electrosteric stabilization of particle suspensions. The remarkable performance of PAZO in its application in EPD have been exemplified by deposition of a wide variety of inorganic materials including the single element oxides (NiO, ZnO, Fe2O3) the complex oxides (Al2TiO5, BaTiO3, ZrSiO4, CoFe2O4) different nitrides (TiN, Si3N4, BN) as well as pure Ni metal and hydrotalcite clay. The use of PAZO can avoid limitation of other dispersing agents in deposition and co-deposition of different materials. Composite films were obtained using PAZO as a co-dispersant for different inorganic materials. The deposit composition, microstructure and deposition yield can be varied. The EPD method offers the advantages of simplicity, high deposition rate, and ability to deposit thin or thick films. PMID:26433084

  3. Methods of capturing and immobilizing radioactive nuclei with metal fluorite-based inorganic materials

    DOEpatents

    Wang, Yifeng; Miller, Andy; Bryan, Charles R.; Kruichak, Jessica Nicole

    2015-11-17

    Methods of capturing and immobilizing radioactive nuclei with metal fluorite-based inorganic materials are described. For example, a method of capturing and immobilizing radioactive nuclei includes flowing a gas stream through an exhaust apparatus. The exhaust apparatus includes a metal fluorite-based inorganic material. The gas stream includes a radioactive species. The radioactive species is removed from the gas stream by adsorbing the radioactive species to the metal fluorite-based inorganic material of the exhaust apparatus.

  4. Methods of capturing and immobilizing radioactive nuclei with metal fluorite-based inorganic materials

    SciTech Connect

    Wang, Yifeng; Miller, Andy; Bryan, Charles R; Kruichar, Jessica Nicole

    2015-04-07

    Methods of capturing and immobilizing radioactive nuclei with metal fluorite-based inorganic materials are described. For example, a method of capturing and immobilizing radioactive nuclei includes flowing a gas stream through an exhaust apparatus. The exhaust apparatus includes a metal fluorite-based inorganic material. The gas stream includes a radioactive species. The radioactive species is removed from the gas stream by adsorbing the radioactive species to the metal fluorite-based inorganic material of the exhaust apparatus.

  5. Soil Inorganic Carbon Formation: Can Parent Material Overcome Climate?

    NASA Astrophysics Data System (ADS)

    Stanbery, C.; Will, R. M.; Seyfried, M. S.; Benner, S. G.; Flores, A. N.; Guilinger, J.; Lohse, K. A.; Good, A.; Black, C.; Pierce, J. L.

    2014-12-01

    Soil carbon is the third largest carbon reservoir and is composed of both organic and inorganic constituents. However, the storage and flux of soil carbon within the global carbon cycle are not fully understood. While organic carbon is often the focus of research, the factors controlling the formation and dissolution of soil inorganic carbon (SIC) are complex. Climate is largely accepted as the primary control on SIC, but the effects of soil parent material are less clear. We hypothesize that effects of parent material are significant and that SIC accumulation will be greater in soils formed from basalts than granites due to the finer textured soils and more abundant calcium and magnesium cations. This research is being conducted in the Reynolds Creek Experimental Watershed (RCEW) in southwestern Idaho. The watershed is an ideal location because it has a range of gradients in precipitation (250 mm to 1200 mm), ecology (sagebrush steppe to juniper), and parent materials (a wide array of igneous and sedimentary rock types) over a relatively small area. Approximately 20 soil profiles will be excavated throughout the watershed and will capture the effects of differing precipitation amounts and parent material on soil characteristics. Several samples at each site will be collected for analysis of SIC content and grain size distribution using a pressure calcimeter and hydrometers, respectively. Initial field data suggests that soils formed over basalts have a higher concentration of SIC than those on granitic material. If precipitation is the only control on SIC, we would expect to see comparable amounts in soils formed on both rock types within the same precipitation zone. However, field observations suggest that for all but the driest sites, soils formed over granite had no SIC detected while basalt soils with comparable precipitation had measurable amounts of SIC. Grain size distribution appears to be a large control on SIC as the sandier, granitic soils promote deeper percolation. This ongoing research will clarify the processes involved in SIC formation and identify the situations where it is an atmospheric source or sink.

  6. Inorganic Materials as Catalysts for Photochemical Splitting of Frank E. Osterloh*

    E-print Network

    Osterloh, Frank

    , light with >300 nm),13 and Cr/Rh-modified GaN/ZnO (QE ) 2.5%, pure water, visible light).14,15 So farReViews Inorganic Materials as Catalysts for Photochemical Splitting of Water Frank E. Osterloh materials have been discovered as catalysts for this reaction. This review discusses the known inorganic

  7. Release of inorganic material during coal devolatilization. Milestone report

    SciTech Connect

    Baxter, L.L.

    1995-07-01

    Experimental results presented in this paper indicate that coal devolatilization products convectively remove a fraction of the nonvolatile components of inorganic material atomically dispersed in the coal matrix. Results from three facilities burning six different coals illustrate this mechanism of ash transformation and release from coal particles. Titanium is chosen to illustrate this type of mass release from coal particles on the basis of its low volatility and mode of occurrence in the coal. During moderate rates of devolatilization (10{sup 4} K/s heating rate), no significant loss of titanium is noted. At more rapid rates of heating/devolatilization (10{sup 5} K/s) a consistent but minor (3-4 %) loss of titanium is noted. During rapid devolatilization (5xl0{sup 5} K/s and higher), significant (10-20 %) amounts of titanium leave the coal. The loss of titanium monitored in coals ranging in rank from subbituminous to high-volatile bituminous coals and under conditions typical of pulverized-coal combustion. The amount of titanium lost during devolatilization exhibits a complex rank dependence. These results imply that other atomically dispersed material (alkali and alkaline earth elements) may undergo similar mechanisms of transformation and release.

  8. Structural diversity in hybrid organic-inorganic lead iodide materials.

    PubMed

    Weber, Oliver J; Marshall, Kayleigh L; Dyson, Lewis M; Weller, Mark T

    2015-12-01

    The structural chemistry of hybrid organic-inorganic lead iodide materials has become of increasing significance for energy applications since the discovery and development of perovskite solar cells based on methylammonium lead iodide. Seven new hybrid lead iodide compounds have been synthesized and structurally characterized using single-crystal X-ray diffraction. The lead iodide units in materials templated with bipyridyl, 1,2-bis(4-pyridyl)ethane, 1,2-di(4-pyridyl)ethylene and imidazole adopt one-dimensional chain structures, while crystallization from solutions containing piperazinium cations generates a salt containing isolated [PbI6](4-) octahedral anions. Templating with 4-chlorobenzylammonium lead iodide adopts the well known two-dimensional layered perovskite structure with vertex shared sheets of composition [PbI4](2-) separated by double layers of organic cations. The relationships between the various structures determined, their compositions, stability and hydrogen bonding between the protonated amine and the iodide ions of the PbI6 octahedra are described. PMID:26634723

  9. Processing and optimization of functional ceramic coatings and inorganic nanomaterials

    NASA Astrophysics Data System (ADS)

    Nyutu, Edward Kennedy G.

    Processing of functional inorganic materials including zero (0-D) dimensional (e.g. nanoparticles), 1-D (nanorods, nanofibers), and 2-D (films/coating) structures is of fundamental and technological interest. This research will have two major sections. The first part of section one focuses on the deposition of silicon dioxide onto a pre-deposited molybdenum disilicide coating on molybdenum substrates for both high (>1000 °C) and moderate (500-600 °C) temperature oxidation protection. Chemical vapor deposition (CVD/MOCVD) techniques will be utilized to deposit the metal suicide and oxide coatings. The focus of this study will be to establish optimum deposition conditions and evaluate the metal oxide coating as oxidation - thermal barriers for Mo substrates under both isothermal (static) and cyclic oxidation conditions. The second part of this section will involve a systematic evaluation of a boron nitride (BN) interface coating prepared by chemical vapor deposition. Ceramic matrix composites (CMCs) are prospective candidates for high (>1000 °C) temperature applications and fiber- matrix interfaces are the dominant design parameters in ceramic matrix composites (CMCs). An important goal of the study is to determine a set of process parameters, which would define a boron nitride (BN) interface coating by a chemical vapor deposition (CVD) process with respect to coating. In the first part of the second section, we will investigate a new approach to synthesize ultrafine metal oxides that combines microwave heating and an in-situ ultrasonic mixing of two or more liquid precursors with a tubular flow reactor. Different metal oxides such as nickel ferrite and zinc aluminate spinels will be studied. The synthesis of metal oxides were investigated in order to study the effects of the nozzle and microwave (INM process) on the purity, composition, and particle size of the resulting powders. The second part of this research section involves a study of microwave frequency effects on the synthesis of nanocrystalline tetragonal barium titanate. The effects of microwave frequency (fixed and variable), microwave bandwidths sweep time, and aging time on the microstructure, particle sizes, phase purity, surface areas, and porosities of the as-prepared BaTiO3 were systematically investigated. The final part of the research involves a new rapid and facile synthetic route to prepare size-tunable, ultranarrow, high surface area OMS-2 nanomaterials via open-vessel microwave-assisted refluxing preparations without employing templates or surfactants. The particle size control is achieved by varying the concentration or type of non-aqueous co-solvent. The structural, textural, and catalytic application properties of the prepared nanomaterials are investigated.

  10. Inorganic arsenic impairs differentiation and functions of human dendritic cells

    SciTech Connect

    Macoch, Mélinda; Morzadec, Claudie; Fardel, Olivier; Pôle Biologie, Centre Hospitalier Universitaire Rennes, 2 rue Henri Le Guilloux, 35033 Rennes ; Vernhet, Laurent

    2013-01-15

    Experimental studies have demonstrated that the antileukemic trivalent inorganic arsenic prevents the development of severe pro-inflammatory diseases mediated by excessive Th1 and Th17 cell responses. Differentiation of Th1 and Th17 subsets is mainly regulated by interleukins (ILs) secreted from dendritic cells (DCs) and the ability of inorganic arsenic to impair interferon-? and IL-17 secretion by interfering with the physiology of DCs is unknown. In the present study, we demonstrate that high concentrations of sodium arsenite (As(III), 1–2 ?M) clinically achievable in plasma of arsenic-treated patients, block differentiation of human peripheral blood monocytes into immature DCs (iDCs) by inducing their necrosis. Differentiation of monocytes in the presence of non-cytotoxic concentrations of As(III) (0.1 to 0.5 ?M) only slightly impacts endocytotic activity of iDCs or expression of co-stimulatory molecules in cells activated with lipopolysaccharide. However, this differentiation in the presence of As(III) strongly represses secretion of IL-12p70 and IL-23, two major regulators of Th1 and Th17 activities, from iDCs stimulated with different toll-like receptor (TLR) agonists in metalloid-free medium. Such As(III)-exposed DCs also exhibit reduced mRNA levels of IL12A and/or IL12B genes when activated with TLR agonists. Finally, differentiation of monocytes with non-cytotoxic concentrations of As(III) subsequently reduces the ability of activated DCs to stimulate the release of interferon-? and IL-17 from Th cells. In conclusion, our results demonstrate that clinically relevant concentrations of inorganic arsenic markedly impair in vitro differentiation and functions of DCs, which may contribute to the putative beneficial effects of the metalloid towards inflammatory autoimmune diseases. Highlights: ? Inorganic arsenic impairs differentiation and functions of human dendritic cells (DCs) ? Arsenite (> 1 ?M) blocks differentiation of dendritic cells by inducing necrosis ? Arsenite (0.1 to 0.5 ?M) slightly reduces endocytotic activity of immature DCs ? Arsenite (0.1 to 0.5 ?M) represses expression of IL-12p70 and IL-23 in activated DCs ? Arsenite (0.1 to 0.5 ?M) reduces the ability of DCs to activate human T lymphocytes.

  11. Inorganic-organic electrolyte materials for energy applications

    NASA Astrophysics Data System (ADS)

    Fei, Shih-To

    This thesis research is devoted to the development of phosphazene-based electrolyte materials for use in various energy applications. Phosphazenes are inorganic-organic materials that provide unusal synthetic advantages and unique process features that make them useful in energy research. This particular thesis consists of six chapters and is focused on four specific aspects: lithium battery, solar cell, and fuel cell electrolytes, and artificial muscles. Chapter 1 is written as an introduction and review of phosphazene electrolytes used in energy applications. In this introduction the basic history and characteristics of the phosphazenes are discussed briefly, followed by examples of current and future applications of phosphazene electrolytes related to energy. Notes are included on how the rest of the chapters relate to previous work. Chapters 2 and 3 discuss the conductivity and fire safety of ethyleneoxy phosphazene gel electrolytes. The current highly flammable configurations for rechargeable lithium batteries generate serious safety concerns. Although commercial fire retardant additives have been investigated, they tend to decrease the overall efficiency of the battery. In these two chapters the discussion is focused on ionically conductive, non-halogenated lithium battery additives based on a methoxyethoxyethoxyphosphazene oligomer and the corresponding high polymer, both of which can increase the fire resistance of a battery while retaining a high energy efficiency. Conductivities in the range of 10 -4 Scm-1 have been obtained for self-extinguishing, ion-conductive methoxyethoxyethoxyphosphazene oligomers. The addition of 25 wt% high polymeric poly[bis(methoxyethoxyethoxy)phosphazene] to propylene carbonate electrolytes lowers the flammability by 90% while maintaining a good ionic conductivity of 2.5x10--3 Scm -1 Chapter 2 is focused more on the electrochemical properties of the electrolytes and how they compare to other similar materials, while Chapter 3 emphasizes the flammability studies. Chapter 4 expands the application of the ethyleneoxy phosphazene system to dye sensitized solar cell systems, and uses this material as a model for the study of electrode-electrolyte interfaces. We report here the results of our study on polymer electrolyte infiltration and its effect on dye-sensitized solar cells. In-depth studies have been made to compare the effects of different cell assembly procedures on the electrochemical properties as well as infiltration of electrolytes into various electrode designs. The first part of the study is based on the use of thermoplastic phosphazene electrolytes and how the overall fabrication procedure affects electrochemical performance, and the second is the use of cross-section microscopy to characterize the degree of electrolyte infiltration into various nanostructured titanium dioxide electrode surfaces. The results of this study should eventually improve the efficiency and longevity of thermally stable polymer dye solar cell systems. In Chapter 5 the effect of pendant polymer design on methanol fuel cell membrane performance was investigated. A synthetic method is described to produce a proton conductive polymer membrane with a polynorbornane backbone and inorganic-organic cyclic phosphazene pendent groups that bear sulfonic acid units. This hybrid polymer combines the inherent hydrophobicity and flexibility of the organic polymer with the tuning advantages of the cyclic phosphazene to produce a membrane with high proton conductivity and low methanol crossover at room temperature. The ion exchange capacity (IEC), the water swelling behavior of the polymer, and the effect of gamma radiation crosslinking were studied, together with the proton conductivity and methanol permeability of these materials. A typical membrane had an IEC of 0.329 mmolg-1 and had water swelling of 50 wt%. The maximum proton conductivity of 1.13x10 -4 Scm-1 at room temperature is less than values reported for some commercially available materials such as Nafion. However the average methanol permeability was aro

  12. Deposition of organic and inorganic materials in crude oil production and processing

    SciTech Connect

    Dickakian, G.

    1996-10-01

    Fouling is the phenomena of the deposition of undesired materials on a metal surface leading to operational problems affecting heat transfer, pressure, flow and production. Fouling of organic and inorganic materials was investigated using a Thermal Fouling Test Unit. Test results showed that the addition of asphaltenes, sea salt, clay, iron sulfide lead to increased fouling of crude oils. Fouling of crude oils is influenced by operating conditions, equipment design and crude oil chemical composition especially asphaltenes, aliphatics, aromatics and inorganic materials. Characterization of deposits from crude oil production and processing shows the presence of asphaltenes, coke and various inorganic materials.

  13. Interfacial and transport properties of nanoconstrained inorganic and organic materials

    NASA Astrophysics Data System (ADS)

    Kocherlakota, Lakshmi Suhasini

    Nanoscale constraints impact the material properties of both organic and inorganic systems. The systems specifically studied here are (i) nanoconstrained polymeric systems, poly(l-trimethylsilyl-1-propyne) (PTMSP) and poly(ethylene oxide) (PEO) relevant to gas separation membranes (ii) Zwitterionic polymers poly(sulfobetaine methacrylate)(pSBMA), poly(carboxybetaine acrylamide) (pCBAA), and poly(oligo(ethylene glycol) methyl methacrylate) (PEGMA) brushes critical for reducing bio-fouling (iii) Surface properties of N-layer graphene sheets. Interfacial constraints in ultrathin poly(l-trimethylsilyl-1-propyne) (PTMSP) membranes yielded gas permeabilities and CO2/helium selectivities that exceed bulk PTMSP membrane transport properties by up to three-fold for membranes of submicrometer thickness. Indicative of a free volume increase, a molecular energetic mobility analysis (involving intrinsic friction analysis) revealed enhanced methyl side group mobilities in thin PTMSP membranes with maximum permeation, compared to bulk films. Aging studies conducted over the timescales relevant to the conducted experiments signify that the free volume states in the thin film membranes are highly unstable in the presence of sorbing gases such as CO2. To maintain this high free volume configuration of polymer while improving the temporal stability an "inverse" architecture to conventional polymer nanocomposites was investigated, in which the polymer phase of PTMSP and PEO were interfacially and dimensionally constrained in nanoporous anodic aluminum oxide (AAO) membranes. While with this architecture the benefits of nanocomposite and ultrathin film membranes of PTMSP could be reproduced and improved upon, also the temporal stability could be enhanced substantially. The PEO-AAO nanocomposite membranes also revealed improved gas selectivity properties of CO2 over helium. In the thermal transition studies of zwitterionic pSBMA brushes a reversible critical transition temperature of 60 °C in 27 nm films was evidenced, indicating changes in molecular conformations with respect to the temperature. pCBAA and pEGMA brushes displayed no thermal transitions, suggesting that the molecular conformations of these systems were insensitive to temperature in the investigated regime. The surface energy of a dimensionally constrained inorganic system, graphene is studied via local Hamaker constant determination from a single graphene layer to bulk graphite. Intrinsic friction scattering analysis of dipolar fluctuations of the Van der Waals interactions between an atomic force microscopy tip and graphene layers revealed a four-fold reduction in the surface energy from bulk HOPG to graphene. A numerical analysis based on electron energy loss spectroscopy confirms quantitatively the results.

  14. Synthesis and applications of bioinspired inorganic nanostructured materials

    NASA Astrophysics Data System (ADS)

    Bassett, David C.

    2011-12-01

    Although the study of biominerals may be traced back many centuries, it is only recently that biological principles have been applied to synthetic systems in processes termed "biomimetic" and "bioinspired" to yield materials syntheses that are otherwise not possible and may also reduce the expenditure of energy and/or eliminate toxic byproducts. Many investigators have taken inspiration from interesting and unusual minerals formed by organisms, in a process termed biomineralisation, to tailor the nanostructure of inorganic materials not necessarily found biogenically. However, the fields of nanoparticle synthesis and biomineralisation remain largely separate, and this thesis is an attempt to apply new studies on biomineralisation to nanomaterials science. Principally among the proteins that influence biomineralisation is a group comprised largely of negatively charged aspartic acid residues present in serum. This study is an investigation determining the ability of these serum proteins and other anolagous biomolecules to stabilise biologically relevant amorphous minerals and influence the formation of a variety of materials at the nanoscale. Three different materials were chosen to demonstrate this effect; gold was templated into nanosized single crystals by the action of bioorganic molecules, and the utility of these nanoparticles as a biosensor was explored. The influence of bioorganic molecules on the phase selection and crystal size restriction of titanium dioxide, an important semiconductor with many applications, was explored. The use of bioorganically derived nanoparticles of titanium dioxide was then demonstrated as a highly efficient photocatalyst. Finally, calcium carbonate, a prevalent biomineral was shown to form highly ordered structures over a variety of length scales and different crystalline polymorphs under the influence of a templating protein. In addition, an alternative route to producing calcium phosphate nanoparticle dispersions by mechanical filtration was explored and use as a transfection vector was optimised in two cell lines. Several significant achievements are presented: (i) the assessment of the relative ability of serum, serum derived proteins and their analogues to stabilize the amorphous state, (ii) the formation of single crystalline gold templated by an antibody, (iii) the formation of highly photocatalytically active nanoparticulate anatase by a phosphorylated cyclic esther, (iv) the formation of conical structures at the air liquid interface by the templating ability of a protein and (v) the optimisation of calcium phosphate nanoparticle mediated transfection in two cell lines by mechanical filtration.

  15. In situ studies of a platform for metastable inorganic crystal growth and materials discovery

    PubMed Central

    Shoemaker, Daniel P.; Hu, Yung-Jin; Chung, Duck Young; Halder, Gregory J.; Chupas, Peter J.; Soderholm, L.; Mitchell, J. F.; Kanatzidis, Mercouri G.

    2014-01-01

    Rapid shifts in the energy, technological, and environmental demands of materials science call for focused and efficient expansion of the library of functional inorganic compounds. To achieve the requisite efficiency, we need a materials discovery and optimization paradigm that can rapidly reveal all possible compounds for a given reaction and composition space. Here we provide such a paradigm via in situ X-ray diffraction measurements spanning solid, liquid flux, and recrystallization processes. We identify four new ternary sulfides from reactive salt fluxes in a matter of hours, simultaneously revealing routes for ex situ synthesis and crystal growth. Changing the flux chemistry, here accomplished by increasing sulfur content, permits comparison of the allowable crystalline building blocks in each reaction space. The speed and structural information inherent to this method of in situ synthesis provide an experimental complement to computational efforts to predict new compounds and uncover routes to targeted materials by design. PMID:25024201

  16. In situ studies of a platform for metastable inorganic crystal growth and materials discovery.

    PubMed

    Shoemaker, Daniel P; Hu, Yung-Jin; Chung, Duck Young; Halder, Gregory J; Chupas, Peter J; Soderholm, L; Mitchell, J F; Kanatzidis, Mercouri G

    2014-07-29

    Rapid shifts in the energy, technological, and environmental demands of materials science call for focused and efficient expansion of the library of functional inorganic compounds. To achieve the requisite efficiency, we need a materials discovery and optimization paradigm that can rapidly reveal all possible compounds for a given reaction and composition space. Here we provide such a paradigm via in situ X-ray diffraction measurements spanning solid, liquid flux, and recrystallization processes. We identify four new ternary sulfides from reactive salt fluxes in a matter of hours, simultaneously revealing routes for ex situ synthesis and crystal growth. Changing the flux chemistry, here accomplished by increasing sulfur content, permits comparison of the allowable crystalline building blocks in each reaction space. The speed and structural information inherent to this method of in situ synthesis provide an experimental complement to computational efforts to predict new compounds and uncover routes to targeted materials by design. PMID:25024201

  17. IRIS Toxicological Review of Inorganic Arsenic (Preliminary Assessment Materials)

    EPA Science Inventory

    In April 2014, EPA released the draft literature searches and associated search strategies, evidence tables, and exposure response arrays for inorganic arsenic (iAs) to obtain input from stakeholders and the public prior to developing the draft IRIS assessment. Specifically, EPA ...

  18. Organic-inorganic materials containing nanoparticles of zirconium hydrophosphate for baromembrane separation

    NASA Astrophysics Data System (ADS)

    Dzyazko, Yuliya S.; Rozhdestvenskaya, Ludmila M.; Zmievskii, Yu G.; Vilenskii, Alexander I.; Myronchuk, Valerii G.; Kornienko, Ludmila V.; Vasilyuk, Sergey V.; Tsyba, Nikolay N.

    2015-02-01

    Organic-inorganic membranes were obtained by stepwise modification of poly(ethyleneterephthalate) track membrane with nanoparticles of zirconium hydrophosphate. The modifier was inserted inside pores of the polymer, a size of which is 0.33 ?m. Inner active layer was formed by this manner. Evolution of morphology and functional properties of the membranes were investigated using methods of porosimetry, potentiometry and electron microscopy. The nanoparticles (4 to 10 nm) were found to form aggregates, which block pores of the polymer. Pores between the aggregates (4 to 8 nm) as well as considerable surface charge density provide significant transport numbers of counter ions (up to 0.86 for Na+). The materials were applied to baromembrane separation of corn distillery. It was found that precipitate is formed mainly inside the pores of the pristine membrane. In the case of the organic-inorganic material, the deposition occurs onto the outer surface and can be removed by mechanical way. Location of the active layer inside membranes protects it against damage.

  19. Transition metal chalcogenides: ultrathin inorganic materials with tunable electronic properties.

    PubMed

    Heine, Thomas

    2015-01-20

    CONSPECTUS: After the discovery of graphene and the development of powerful exfoliation techniques, experimental preparation of two-dimensional (2D) crystals can be expected for any layered material that is known to chemistry. Besides graphene and hexagonal boron nitride (h-BN), transition metal chalcogenides (TMC) are among the most studied ultrathin materials. In particular, single-layer MoS2, a direct band gap semiconductor with ?1.9 eV energy gap, is popular in physics and nanoelectronics, because it nicely complements semimetallic graphene and insulating h-BN monolayer as a construction component for flexible 2D electronics and because it was already successfully applied in the laboratory as basis material for transistors and other electronic and optoelectronic devices. Two-dimensional crystals are subject to significant quantum confinement: compared with their parent layered 3D material, they show different structural, electronic, and optical properties, such as spontaneous rippling as free-standing monolayer, significant changes of the electronic band structure, giant spin-orbit splitting, and enhanced photoluminescence. Most of those properties are intrinsic for the monolayer and already absent for two-layer stacks of the same 2D crystal. For example, single-layer MoS2 is a direct band gap semiconductor with spin-orbit splitting of 150 meV in the valence band, while the bilayer of the same material is an indirect band gap semiconductor without observable spin-orbit splitting. All these properties have been observed experimentally and are in excellent agreement with calculations based on density-functional theory. This Account reports theoretical studies of a subgroup of transition metal dichalcogenides with the composition MX2, with M = Mo, or W and X = Se or S, also referred to as "MoWSeS materials". Results on the electronic structure, quantum confinement, spin-orbit coupling, spontaneous monolayer rippling, and change of electronic properties in the presence of an external electric field are reported. While all materials of the MoWSeS family share the same qualitative properties, their individual values can differ strongly, for example, the spin-orbit splitting in WSe2 reaches the value of 428 meV, nearly three times that of MoS2. Further, we discuss the effect of strain on the electronic properties (straintronics). While MoWSeS single layers are very robust against external electric fields, bilayers show a linear reduction of the band gap, even reaching a semiconductor-metal phase transition, and an increase of the spin-orbit splitting from zero to the monolayer value at rather small fields. Strain is yet another possibility to control the band gap in a linear way, and MoWSeS monolayers become metallic at strain values of ?10%. The density-functional based tight-binding model is a useful tool to investigate the electronic and structural properties, including electron conductance, of large MoS2 structures, which show spontaneous rippling in finite-temperature molecular dynamics simulations. Structural defects in MoS2 result in anisotropy of the electric conductivity. Finally, DFT predictions on the properties of noble metal dichalcogenides are presented. Most strikingly, 1T PdS2 is an indirect band gap semiconductor in its monolayer form but becomes metallic as a bilayer. PMID:25489917

  20. Lunar building materials: Some considerations on the use of inorganic polymers. [adhesives, coatings, and binders

    NASA Technical Reports Server (NTRS)

    Lee, S. M.

    1979-01-01

    The use of inorganic polymer systems synthesized from the available lunar chemical elements, viz., silicon, aluminum, and oxygen to make adhesives, binders, and sealants needed in the fabrication of lunar building materials and the assembly of structures is considered. Inorganic polymer systems, their background, status, and shortcomings, and the use of network polymers as a possible approach to synthesis are examined as well as glassy metals for unusual structural strength, and the use of cold-mold materials as well as foam-sintered lunar silicates for lightweight shielding and structural building materials.

  1. Replicated, high-aspect-ratio micro-optical components fabricated from inorganic solgel materials.

    PubMed

    Krause, Holger; Mönch, Wolfgang; Zappe, Hans

    2006-07-10

    A replication process for the fabrication of refractive microlenses from a purely inorganic solgel material based on tetraethoxysilane is presented. The geometrical dimensions and optical properties of the inorganic microlenses are characterized and compared with those of microlenses replicated in a hybrid xerogel containing organic additives. By a reduced solvent content in the sol composition, together with modifications in the replication process, it was possible to obtain inorganic xerogel lenses with exceptionally high sagittal height values of as much as 28 microm. Compared with the hybrid xerogel, the inorganic xerogel has the advantage of an absorption coefficient that is five times lower in the visible spectral range and exhibits optical transparency in the near-ultraviolet range for wavelengths down to 200 nm. PMID:16807590

  2. Nanoscale Structure of Self-Assembling Hybrid Materials of Inorganic and Electronically Active Organic Phases

    SciTech Connect

    Sofos, M.; Goswami, D.A. Stone D.K.; Okasinski, J.S.; Jin, H.; Bedzyk, M.J.; Stupp, S.I.

    2008-10-06

    Hybrid materials with nanoscale structure that incorporates inorganic and organic phases with electronic properties offer potential in an extensive functional space that includes photovoltaics, light emission, and sensing. This work describes the nanoscale structure of model hybrid materials with phases of silica and electronically active bola-amphiphile assemblies containing either oligo(p-phenylene vinylene) or oligo(thiophene) segments. The hybrid materials studied here were synthesized by evaporation-induced self-assembly and characterized by X-ray scattering techniques. Grazing-incidence X-ray scattering studies of these materials revealed the formation of two-dimensional hexagonally packed cylindrical micelles of the organic molecules with diameters between 3.1 and 3.6 nm and cylindrical axes parallel to the surface. During the self-assembly process at low pH, the cylindrical aggregates of conjugated molecules become surrounded by silica giving rise to a hybrid structure with long-range order. Specular X-ray reflectivity confirmed the long-range periodicity of the hybrid films within a specific range of molar ratios of tetraethyl orthosilicate to cationic amphiphile. We did not observe any long-range ordering in fully organic analogues unless quaternary ammonium groups were replaced by tertiary amines. These observations suggest that charge screening in these biscationic conjugated molecules by the mineral phase is a key factor in the evolution of long range order in the self-assembling hybrids.

  3. Tidal day organic and inorganic material flux of ponds in the Liberty Island freshwater tidal wetland.

    PubMed

    Lehman, Peggy W; Mayr, Shawn; Liu, Leji; Tang, Alison

    2015-01-01

    The loss of inorganic and organic material export and habitat produced by freshwater tidal wetlands is hypothesized to be an important contributing factor to the long-term decline in fishery production in San Francisco Estuary. However, due to the absence of freshwater tidal wetlands in the estuary, there is little information on the export of inorganic and organic carbon, nutrient or phytoplankton community biomass and the associated mechanisms. A single-day study was conducted to assess the potential contribution of two small vegetated ponds and one large open-water pond to the inorganic and organic material flux within the freshwater tidal wetland Liberty Island in San Francisco Estuary. The study consisted of an intensive tidal day (25.5 h) sampling program that measured the flux of inorganic and organic material at three ponds using continuous monitoring of flow, chlorophyll a, turbidity and salt combined with discrete measurements of phytoplankton community carbon, total and dissolved organic carbon and nutrient concentration at 1.5 h intervals. Vegetated ponds had greater material concentrations than the open water pond and, despite their small area, contributed up to 81% of the organic and 61% of the inorganic material flux of the wetland. Exchange between ponds was important to wetland flux. The small vegetated pond in the interior of the wetland contributed as much as 72-87% of the total organic carbon and chlorophyll a and 10% of the diatom flux of the wetland. Export of inorganic and organic material from the small vegetated ponds was facilitated by small-scale topography and tidal asymmetry that produced a 40% greater material export on ebb tide. The small vegetated ponds contrasted with the large open water pond, which imported 29-96% of the inorganic and 4-81% of the organic material into the wetland from the adjacent river. This study identified small vegetated ponds as an important source of inorganic and organic material to the wetland and the importance of small scale physical processes within ponds to material flux of the wetland. PMID:26090320

  4. Hybrid materials based on organic luminophores in inorganic glass matrix

    NASA Astrophysics Data System (ADS)

    Petrova, O. B.; Avetisov, R. I.; Avetisov, I. Kh.; Mushkalo, O. A.; Khomyakov, A. V.; Cherednichenko, A. G.

    2013-06-01

    Hybrid materials were synthesized based on borate glass matrix and the tris(8-hydroxyquinoline) aluminum (Alq3) organic luminophore, which is used as a green luminophore in OLED devices. The luminescent properties of hybrid materials with 0.02-0.1 wt % of Alq3 in glass were studied. The luminescence peak of the hybrid material is significantly shifted to shorter wavelengths (443 nm versus 518 nm in pure Alq3 powder).

  5. Engineered biomolecular interactions with inorganic materials : sequence, binding, and assembly

    E-print Network

    Peelle, Beau R

    2005-01-01

    Nanobiotechnology aims to exploit biomolecular recognition and self-assembly capabilities for integrating advanced materials into medicine and electronics. In particular, peptides have exhibited the ability to specifically ...

  6. Functioning of inorganic/organic battery separators in silver-zinc cells

    NASA Technical Reports Server (NTRS)

    Philipp, W. H.; May, C. E.

    1976-01-01

    The results of three experimental studies related to the inorganic/organic battery separator operating mechanism are described: saponification of the plasticizer, resistivity of the simulated separators, and zincate diffusion through the separators. The inorganic/organic separator appears to be a particular example of a general class of ionic conducting films composed of inorganic fillers and/or substrates bonded together by an organic polymer containing an incompatible plasticizer that may be leached by the electrolyte. The I/O separator functions as a microporous film of varying tortuosity with essentially no specific chemical inhibition to zincate diffusion.

  7. Synthesis and characterization of inorganic nanostructured materials for advanced energy storage

    NASA Astrophysics Data System (ADS)

    Xie, Jin

    The performance of advanced energy storage devices is intimately connected to the designs of electrodes. To enable significant developments in this research field, we need detailed information and knowledge about how the functions and performances of the electrodes depend on their chemical compositions, dimensions, morphologies, and surface properties. This thesis presents my successes in synthesizing and characterizing electrode materials for advanced electrochemical energy storage devices, with much attention given to understanding the operation and fading mechanism of battery electrodes, as well as methods to improve their performances and stabilities. This dissertation is presented within the framework of two energy storage technologies: lithium ion batteries and lithium oxygen batteries. The energy density of lithium ion batteries is determined by the density of electrode materials and their lithium storage capabilities. To improve the overall energy densities of lithium ion batteries, silicon has been proposed to replace lithium intercalation compounds in the battery anodes. However, with a ~400% volume expansion upon fully lithiation, silicon-based anodes face serious capacity degradation in battery operation. To overcome this challenge, heteronanostructure-based Si/TiSi2 were designed and synthesized as anode materials for lithium ion batteries with long cycling life. The performance and morphology relationship was also carefully studied through comparing one-dimensional and two-dimensional heteronanostructure-based silicon anodes. Lithium oxygen batteries, on the other hand, are devices based on lithium conversion chemistries and they offer higher energy densities compared to lithium ion batteries. However, existing carbon based electrodes in lithium oxygen batteries only allow for battery operation with limited capacity, poor stability and low round-trip efficiency. The degradation of electrolytes and carbon electrodes have been found to both contribute to the challenges. The understanding of the synergistic effect between electrolyte decomposition and electrode decomposition, nevertheless, is conspicuously lacking. To better understand the reaction chemistries in lithium oxygen batteries, I designed, synthesized, and studied heteronanostructure-based carbon-free inorganic electrodes, as well as carbon electrodes whose surfaces protected by metal oxide thin films. The new types of electrodes prove to be highly effective in minimizing parasitic reactions, reducing operation overpotentials and boosting battery lifetimes. The improved stability and well-defined electrode morphology also enabled detailed studies on the formation and decomposition of Li2O 2. To summarize, this dissertation presented the synthesis and characterization of inorganic nanostructured materials for advanced energy storage. On a practical level, the new types of materials allow for the immediate advancement of the energy storage technology. On a fundamental level, it helped to better understand reaction chemistries and fading mechanisms of battery electrodes.

  8. Graded porous inorganic materials derived from self-assembled block copolymer templates

    NASA Astrophysics Data System (ADS)

    Gu, Yibei; Werner, Jörg G.; Dorin, Rachel M.; Robbins, Spencer W.; Wiesner, Ulrich

    2015-03-01

    Graded porous inorganic materials directed by macromolecular self-assembly are expected to offer unique structural platforms relative to conventional porous inorganic materials. Their preparation to date remains a challenge, however, based on the sparsity of viable synthetic self-assembly pathways to control structural asymmetry. Here we demonstrate the fabrication of graded porous carbon, metal, and metal oxide film structures from self-assembled block copolymer templates by using various backfilling techniques in combination with thermal treatments for template removal and chemical transformations. The asymmetric inorganic structures display mesopores in the film top layers and a gradual pore size increase along the film normal in the macroporous sponge-like support structure. Substructure walls between macropores are themselves mesoporous, constituting a structural hierarchy in addition to the pore gradation. Final graded structures can be tailored by tuning casting conditions of self-assembled templates as well as the backfilling processes. We expect that these graded porous inorganic materials may find use in applications including separation, catalysis, biomedical implants, and energy conversion and storage.Graded porous inorganic materials directed by macromolecular self-assembly are expected to offer unique structural platforms relative to conventional porous inorganic materials. Their preparation to date remains a challenge, however, based on the sparsity of viable synthetic self-assembly pathways to control structural asymmetry. Here we demonstrate the fabrication of graded porous carbon, metal, and metal oxide film structures from self-assembled block copolymer templates by using various backfilling techniques in combination with thermal treatments for template removal and chemical transformations. The asymmetric inorganic structures display mesopores in the film top layers and a gradual pore size increase along the film normal in the macroporous sponge-like support structure. Substructure walls between macropores are themselves mesoporous, constituting a structural hierarchy in addition to the pore gradation. Final graded structures can be tailored by tuning casting conditions of self-assembled templates as well as the backfilling processes. We expect that these graded porous inorganic materials may find use in applications including separation, catalysis, biomedical implants, and energy conversion and storage. Electronic supplementary information (ESI) available: Additional SEM images, supporting experimental details, TGA analyses and XRD pattern. See DOI: 10.1039/c4nr07492k

  9. Novel hybrid organic-inorganic sol-gel materials based on highly efficient heterocyclic push-pull chromophores

    NASA Astrophysics Data System (ADS)

    Abbotto, Alessandro; Bozio, Renato; Brusatin, Giovanna; Facchetti, Antonio; Guglielmi, Massimo; Innocenzi, Plinio; Meneghetti, Moreno; Pagani, Giorgio A.; Signorini, Raffaella

    1999-10-01

    We report the synthesis of sol-gel materials based on highly efficient heterocycle-based push-pull chromophores showing second- and third-order nonlinear optical activity. We show the proper functionalization of the best performing chromophores and their incorporation into a hybrid organic- inorganic sol-gel matrix. Different types of functionalization of the active molecule have been considered, including hydroxyl and alkoxysilyl end-groups. The functionalization strategy responded to different criteria such as stability and synthetic availability of the final molecular precursors, their solubility, and the used synthetic approach to the sol-gel material. The synthesis of the sol-gel materials has been tuned in order to preserve molecular properties and control important factors such as final concentration of the active dye in the matrix. Both acid- and base-catalyzed sol-gel synthesis has been taken into account. 3-Glycidoxypropyltrimethoxysilane and 3- aminopropyltriethoxysilane have been used as the organically modified alkoxides to prepare the hybrid organic-inorganic matrix. Characterization of the spectroscopic properties of the sol-gel materials is presented.

  10. Surfactants as Promising Media for the Preparation of Crystalline Inorganic Materials.

    PubMed

    Xiong, Wei-Wei; Zhang, Qichun

    2015-09-28

    Given that surfactants can control the shape and size of micro-/nanoparticles, they should be able to direct the growth of bulk crystals. This Minireview summarizes recent developments in the application of surfactants for the preparation of new crystalline inorganic materials, including chalcogenides, metal-organic frameworks, and zeolite analogues. The roles of surfactants in different reaction systems are discussed. PMID:26266458

  11. IRIS Toxicological Review for Inorganic Arsenic (Scoping and Problem Formulation Materials)

    EPA Science Inventory

    In November 2012, EPA released scoping and problem formulation materials for the IRIS assessment of inorganic arsenic for public comment and discussion. The scoping information was based on input from EPA's program and regional offices and was provided for informational purposes....

  12. Inorganic chemical analysis of environmental materials—A lecture series

    USGS Publications Warehouse

    Crock, J.G.; Lamothe, P.J.

    2011-01-01

    At the request of the faculty of the Colorado School of Mines, Golden, Colorado, the authors prepared and presented a lecture series to the students of a graduate level advanced instrumental analysis class. The slides and text presented in this report are a compilation and condensation of this series of lectures. The purpose of this report is to present the slides and notes and to emphasize the thought processes that should be used by a scientist submitting samples for analyses in order to procure analytical data to answer a research question. First and foremost, the analytical data generated can be no better than the samples submitted. The questions to be answered must first be well defined and the appropriate samples collected from the population that will answer the question. The proper methods of analysis, including proper sample preparation and digestion techniques, must then be applied. Care must be taken to achieve the required limits of detection of the critical analytes to yield detectable analyte concentration (above "action" levels) for the majority of the study's samples and to address what portion of those analytes answer the research question-total or partial concentrations. To guarantee a robust analytical result that answers the research question(s), a well-defined quality assurance and quality control (QA/QC) plan must be employed. This QA/QC plan must include the collection and analysis of field and laboratory blanks, sample duplicates, and matrix-matched standard reference materials (SRMs). The proper SRMs may include in-house materials and/or a selection of widely available commercial materials. A discussion of the preparation and applicability of in-house reference materials is also presented. Only when all these analytical issues are sufficiently addressed can the research questions be answered with known certainty.

  13. Dark inorganic carbon fixation sustains the functioning of benthic deep-sea ecosystems

    NASA Astrophysics Data System (ADS)

    Molari, Massimiliano; Manini, Elena; Dell'Anno, Antonio

    2013-01-01

    studies have provided evidence that dark inorganic carbon fixation is an important process for the functioning of the ocean interior. However, its quantitative relevance and ecological significance in benthic deep-sea ecosystems remain unknown. We investigated the rates of inorganic carbon fixation together with prokaryotic abundance, biomass, assemblage composition, and heterotrophic carbon production in surface sediments of different benthic deep-sea systems along the Iberian margin (northeastern Atlantic Ocean) and in the Mediterranean Sea. Inorganic carbon fixation rates in these surface deep-sea sediments did not show clear depth-related patterns, and, on average, they accounted for 19% of the total heterotrophic biomass production. The incorporation rates of inorganic carbon were significantly related to the abundance of total Archaea (as determined by catalyzed reporter deposition fluorescence in situ hybridization) and completely inhibited using an inhibitor of archaeal metabolism, N1-guanyl-1,7-diaminoheptane. This suggests a major role of the archaeal assemblages in inorganic carbon fixation. We also show that benthic archaeal assemblages contribute approximately 25% of the total 3H-leucine incorporation. Inorganic carbon fixation in surface deep-sea sediments appears to be dependent not only upon chemosynthetic processes but also on heterotrophic/mixotrophic metabolism, as suggested by estimates of the chemolithotrophic energy requirements and the enhanced inorganic carbon fixation due to the increase in the availability of organic trophic resources. Overall, our data suggest that archaeal assemblages of surface deep-sea sediments are responsible for the high rates of inorganic carbon incorporation and thereby sustain the functioning of the food webs as well as influence the carbon cycling of benthic deep-sea ecosystems.

  14. Laboratory illustrations of the transformations and deposition of inorganic material in biomass boilers

    SciTech Connect

    Baxter, L.L.; Jenkins, B.M.

    1995-08-01

    Boilers fired with certain woody biomass fuels have proven to be a viable, reliable means of generating electrical power. The behavior of the inorganic material in the fuels is one of the greatest challenges to burning the large variety of fuels available to biomass combustors. Unmanageable ash deposits and interactions between ash and bed material cause loss in boiler availability and significant increase in maintenance costs. The problems related to the behavior of inorganic material now exceed all other combustion-related challenges in biomass-fired boilers. This paper reviews the mechanisms of ash deposit formation, the relationship between fuel properties and ash deposit properties, and a series of laboratory tests in Sandia`s Multifuel Combustor designed to illustrate how fuel type, boiler design, and boiler operating conditions impact ash deposit properties.

  15. Intrinsic mechanical properties and strengthening methods in inorganic crystalline materials

    NASA Astrophysics Data System (ADS)

    Mecking, H.; Hartig, Ch.; Seeger, J.

    1991-06-01

    The paper deals with strength and fracture in metals, ceramics and intermetallic compounds. The emphasis is on the interrelation between microstructure and macroscopic behavior and how the concepts for alloy design are mirroring this interrelationship. The three materials classes are distinguished by the physical nature of the atomic bonding forces. In metals metallic bonding predominates which causes high ductility but poor strength. Accordingly material development concentrates on production of microstructures which optimize the yield strength without unacceptable loss in ductility. In ceramics covalent bonding prevails which results in high hardness and high elastic stiffness but at the same time extreme brittleness. Contrary to the metal-ease material development aims at a kind of pseudo ductility in order to rise the fracture toughness to sufficiently high levels. In intermetallic phases the atomic bonds are a mixture of metallic and covalent bonding where depending on the alloying system the balance between the two contributions may be quite different. Accordingly the properties of intermetallics are in the range between metals and ceramics. By a variety of microstructural measures their properties can be changed in direction. either towards metallic or ceramic behavior. General rules for alloy design are not available, rather every system demands very specific experience since properties depend to a considerable part on intrinsic properties of lattice defects such as dislocations, antiphase boundaries, stacking faults and grain boundaries. Cet article traite de la résistance et de la fracture des métaux, des céramiques et des composés intermétalliques. L'accent est mis sur les correspondances entre la microstructure et le comportement macroscopique ainsi que sur la façon dont de tels concepts se reflètent dans la création de nouveaux alliages. C'est la nature des forces de liaisons qui distingue chaque type de matériaux. Dans les métaux, les liaisons métalliques dominent, ce qui entraîne une grande ductilité mais une médiocre résistance. En conséquence, dans le développement de nouveaux matériaux on cherche préférentiellement à produire des microstructures qui optimisent la résistance élastique sans perte inacceptable de ductilité. Dans les céramiques, les liaisons covalentes prédominent; ceci entraîne une dureté élevée, une grande rigidité, mais en même temps une extrême fragilité. Au contraire des métaux, le développement de ces matériaux vise à obtenir une pseudoductilité afin d'amener la tenacité à des niveaux suffisamment élevés. Dans les phases intermétalliques les liaisons atomiques correspondent à un mélange de liaisons métalliques et covalentes. La contribution de chacune d'entre elles varie en fonction du système allié. En conséquence, les propriétés des intermétalliques se situent entre celles des métaux et des céramiques. Par divers changements microstructuraux des propriétés peuvent être déplacées pour se rapprocher d'un comportement de type métallique ou de type céramique. Donner des règles générales pour la création de nouveaux alliages n'est pas possible car chaque système demande à être testé, les propriétés dépendent en effet, pour une part considérable, des propriétés intrinsèques des défauts de réseau comme les dislocations, les parois d'antiphase ou les joints de grains.

  16. Nanostructured inorganic materials: Synthesis and associated electrochemical properties

    NASA Astrophysics Data System (ADS)

    Yau, Shali Zhu

    Synthetic strategy for preparing potential battery materials at low temperature was developed. Magnetite (Fe3O4), silver hollandnite (AgxMn8O16), magnesium manganese oxide (MgxMnO 2?yH2O), and silver vanadium phosphorous oxide (Ag 2VO2PO4) were studied. Magnetite (Fe3O4) was prepared by coprecipitation induced by triethylamine from aqueous iron(II) and iron(III) chloride solutions of varying concentrations. Variation of the iron(II) and iron(III) concentrations results in crystallite size control of the Fe3O4 products. Materials characterization of the Fe3O4 samples is reported, including Brunauer-Emmitt-Teller (BET) surface area, x-ray powder diffraction (XRD), transmission electron microscopy (TEM), particle size, and saturation magnetization results. A strong correlation between discharge capacity and voltage recovery behavior versus crystallite size was observed when tested as an electrode material in lithium electrochemical cells. Silver hollandite (AgxMn8O16) was successfully synthesized through a low temperature reflux reaction. The crystallite size and silver content of AgxMn8O16 by varying the reactant ratio of silver permanganate (AgMnO4) and manganese sulfate monohydrate (MnSO4?H2O). Silver hollandite was characterized by Brunauer-Emmitt-Teller (BET) surface area, inductively coupled plasma-optical emission (ICP-OES) spectrometry, helium pycnometry, simultaneous thermogravimetric analysis/differential scanning calorimetry (TGA/DSC), and x-ray powder diffraction (XRD). The crystallite size showed a strong correlation with silver content, BET surface area, and particle sizes. The silver hollandite cathode showed good discharge capacity retention in 30 cycles of discharge-charge. There were a good relationship between crystallite size and rate capability and pulse ability. Magnesium manganese oxide (MgxMnO2?yH 2O) was made by redox reaction by mixing sodium hydroxide (NaOH), manganese sulfate monohydrate (MnSO4?HO2), and potassium persulfate (K2S2O8). The solid samples were characterized by inductively coupled plasma-optical emission (ICP-OES) spectrometry, scanning electron microscopy (SEM), simultaneous thermogravimetric analysis/differential scanning calorimetry (TGA/DSC), and X-ray powder diffraction (XRD). The solid had a plate-like morphology. The preliminary electrochemical results showed that MgxMnO2?yH2O had a very good cycliability and the capacity retention in 20 discharge-charge cycles. When the sample was dried at 100°C after collection, the discharge capacity would increase from 80 mAh/g to 155 mAh/g in the first discharge process in cycling test. Silver vanadium phosphorous oxide (SVPO, Ag2VO2PO 4) was prepared in various reaction temperatures. It was the first time that Ag2VO2PO4 was synthesized successfully at room temperature. The solid was characterized by Brunauer-Emmitt-Teller surface area (BET), inductively coupled plasma-optical emission (ICP-OES) spectroscopy, differential scanning calorimetry (DSC), magnetic susceptibility measurement, scanning electron microscope (SEM) and x-ray powder diffraction (XRD). Ag2VO2PO4 crystallite sizes showed a strong linear correlation with reaction temperature. The BET surface area was decreased as the crystallite size increased linearly. In addition, the acicular morphology started to develop at 50°C. The impact of silver deposition loading on the silver-polypyrrole composite electrode was studied using cyclic voltammetry. The minimum Ag loading of 0.08 mg/cm2 was determined to maximize the oxygen reduction activity for the Ag/Ppy composite catalyst. In addition, the Ag/Ppy coated carbon electrode showed higher oxygen reduction activities in both air and oxygen compared to the uncoated carbon electrode.

  17. PEGylated Inorganic Nanoparticles

    SciTech Connect

    Karakoti, Ajay S.; Das, Soumya; Thevuthasan, Suntharampillai; Seal, Sudipta

    2011-02-25

    Application of inorganic nanoparticles in diagnosis and therapy has become a critical component in targeted treatment of diseases. The surface modification of inorganic oxides is important for providing diversity in size, shape, solubility, long term stability and attachment of selective functional groups. PEGylation of surfaces is a key strategic approach for providing stealth characteristics to nanomaterials otherwise identified as foreign materials by human body. The current review describes the role of surface modification of oxides by polyethylene glycol (PEG) in providing versatile characteristics to inorganic oxide nanoparticles with a focus on their biomedical applications. The role of PEG as structure directing agent in synthesis of oxides is also captured in this short review.

  18. Comparison of the biological NH3 removal characteristics among four inorganic packing materials.

    PubMed

    Hirai, M; Kamamoto, M; Yani, M; Shoda, M

    2001-01-01

    Four inorganic packing materials were evaluated in terms of their availability as a packing material of a packed tower deodorization apparatus (biofilter) from the viewpoints of biological NH3 removal characteristics and some physical properties. Porous ceramics (A), calcinated cristobalite (B), calcinated and formed obsidian (C), granulated and calculated soil (D) were used. The superiority of these packing materials determined based on the values of non-biological removal per unit weight or unit volume of packing material, complete removal capacity of NH3 per unit weight of packing material per day or unit volume of packing material per day and pressure drop of the packed bed was in the order of A approximately = C > B > or = D. Packing materials A and C with high porosity, maximum water content, and suitable mean pore diameter showed excellent removal capacity. PMID:16233018

  19. All-Inorganic Colloidal Perovskite Quantum Dots: A New Class of Lasing Materials with Favorable Characteristics.

    PubMed

    Wang, Yue; Li, Xiaoming; Song, Jizhong; Xiao, Lian; Zeng, Haibo; Sun, Handong

    2015-11-01

    All-inorganic colloidal cesium lead halide perovskite quantum dots (CsPbX3 , X = Cl, Br, I) are revealed to be a new class of favorable optical-gain materials, which show -combined merits of both colloidal quantum dots and halide perovskites. Low-threshold and -ultrastable stimulated emission is -demonstrated under atmospheric conditions with wavelength tunability across the whole -visible spectrum via either size or composition control. PMID:26448638

  20. Supramolecularly self-organized nanomaterials: A voyage from inorganic particles to organic light-harvesting materials

    NASA Astrophysics Data System (ADS)

    Varotto, Alessandro

    In 2009 the U.S. National Science Foundation announced the realignment of the Chemistry Divisions introducing the new interdisciplinary program of "Macromolecular, Supramolecular and Nanochemistry." This statement officially recognizes a field of studies that has already seen the publication of many thousands of works in the past 20 years. Nanotechnology and supramolecular chemistry can be found in the most diverse disciplines, from biology to engineering, to physics. Furthermore, many technologies rely on nanoscale dimensions for more than one component. Nanomaterials and technologies are on the market with a range of applications from composite materials, to electronics, to medicine, to sensing and more. This thesis will introduce a variety of studies and applications of supramolecular chemistry to form nanoscale photonic materials from soft matter. We will first illustrate a method to synthesize metallic nanoparticles using plasmids DNA as a mold. The circular DNA functions as a sacrificial template to shape the particles into narrowly monodispersed nanodiscs. Secondly, we will describe the synthesis of a highly fluorinated porphyrin derivative and how the fluorines improve the formation of ultra thin films when the porphyrin is blended with fullerene C60. Finally, we will show how to increase the short-circuit current in a solar cell built with an internal parallel tandem light harvesting design. A blend of phthalocyanines, each with a decreasing optical band gap, is supramolecularly self-organized with pyridyl-C60 within thin films. The different band gaps of the single phthalocyanines capture a wider segment of the solar spectrum increasing the overall efficiency of the device. In conclusion, we have presented a number of studies for the preparation of inorganic and organic nanomaterials and their application in supramolecularly organized photonic devices.

  1. Comparison of the biological H2S removal characteristics among four inorganic packing materials.

    PubMed

    Hirai, M; Kamamoto, M; Yani, M; Shoda, M

    2001-01-01

    Four inorganic packing materials were evaluated in terms of their availability as packing materials of a packed tower deodorization apparatus (biofilter) from the viewpoints of biological H2S removal characteristics and some physical properties. Among porous ceramics (A), calcinated cristobalite (B), calcinated and formed obsidian (C), granulated and calcinated soil (D), the superiority of these packing materials determined based on the values of non-biological removal per unit weight or unit volume of packing material, complete removal capacity of H2S per unit weight of packing material per day or unit volume of packing material per day and pressure drop of the packed bed was in the order of A approximately equal to C > D approximately equal to B, which is correlated with the maximum water content, porosity, and mean pore diameter. PMID:16233011

  2. Use of reinforced inorganic cement materials for spark wire and drift chamber wire frames

    NASA Technical Reports Server (NTRS)

    1987-01-01

    The results of a survey, materials test, and analysis study directed toward the development of an inorganic glass-fiber reinforced cement material for use in the construction of space qualified spark wire frames and drift chamber frames are presented. The purpose for this research was to evaluate the feasibility of using glass fiber reinforced cement (GFRC) for large dimensioned structural frames for supporting a number of precisely located spark wires in multiple planes. A survey of the current state of the art in fiber reinforced cement materials was made; material sample mixes were made and tested to determine their laboratory performances. Tests conducted on sample materials showed that compressive and flexural strengths of this material could approach values which would enable fabrication of structural spark wire frames.

  3. Effect of electric pulse processing on physical and chemical properties of inorganic materials

    NASA Astrophysics Data System (ADS)

    Sakipova, S. E.; Nussupbekov, B. R.; Ospanova, D.; Khassenov, A.; Sakipova, Sh E.

    2015-04-01

    This article analyzes various aspects of the practical application of electric pulse technology of industrial raw materials processing as a result of a spark electric discharge in a liquid solution of the raw material under processing. The object of the study are samples of technogenic materials from a deposit in Central Kazakhstan, which are crushed and ground to particles with a preset degree of fragmentation. The electric pulse processing is performed by using different numbers of discharges. The effect of electric pulse processing with different electrical parameters is carried out on the basis of comparison of the properties and structure of metal-containing and industrial raw materials after machining and electric pulse processing. The X-ray spectral microanalysis was performed using a scanning microscope. The researchers obtained data on changes in the microstructure and elemental composition of inorganic material samples as a result of electric pulse processing. It was established that the technology of electric pulse crushing and grinding of inorganic materials makes it possible to obtain not only a final product with desired size of dispersed particles, but also to change their physical and chemical properties.

  4. Cryogenic Properties of Inorganic Insulation Materials for ITER Magnets: A Review

    SciTech Connect

    Simon, N.J.

    1994-12-01

    Results of a literature search on the cryogenic properties of candidate inorganic insulators for the ITER TF magnets are reported. The materials investigated include: Al{sub 2}O{sub 3}, AlN, MgO, porcelain, SiO{sub 2}, MgAl{sub 2}O{sub 4}, ZrO{sub 2}, and mica. A graphical presentation is given of mechanical, elastic, electrical, and thermal properties between 4 and 300 K. A companion report reviews the low temperature irradiation resistance of these materials.

  5. Design of Bioactive Organic-inorganic Hybrid Materials with Self-setting Ability

    NASA Astrophysics Data System (ADS)

    Miyazaki, T.; Machida, S.; Morita, Y.; Ishida, E.

    2011-10-01

    Paste-like materials with ability of self-setting are attractive for bone substitutes, since they can be injected from the small hole with minimized invasion to the patient. Although bone cements which set as apatite are clinically used, there is limitation on clinical applications due to their mechanical properties such as high brittleness and low fracture toughness. To overcome this problem, organic-inorganic hybrids based on a flexible polymer are attractive. We have obtained an idea for design of self-setting hybrids using polyion complex fabricated by ionic interaction of anionic and cationic polymers. We aimed at preparation of organic-inorganic hybrids exhibiting self-setting ability and bioactivity. The liquid component was prepared from cationic chitosan aqueous solution. The powder component was prepared by mixing various carrageenans with ?-tricalcium phosphate (?-TCP). The obtained cements set within 1 day. Compressive strength showed tendency to increase with increase in ?-TCP content in the powder component. The prepared cements formed the apatite in simulated body fluid within 3 days. Novel self-setting materials based on organic-inorganic hybrid can be designed utilizing ionic interaction of polysaccharide.

  6. High yield production of inorganic graphene-like materials (MoS?, WS?, BN) through liquid exfoliation testing key parameters

    E-print Network

    Pu, Fei, S.B. Massachusetts Institute of Technology

    2012-01-01

    Inorganic graphene-like materials such as molybdenum disulfide (MoS?), tungsten sulfide (WS?), and boron nitride (BN) are known to have electronic properties. When exfoliated into layers and casted onto carbon nanofilms, ...

  7. International Scientific Conference on "Radiation-Thermal Effects and Processes in Inorganic Materials"

    NASA Astrophysics Data System (ADS)

    2015-04-01

    The International Scientific Conference on "Radiation-Thermal Effects and Processes in Inorganic Materials" is a traditional representative forum devoted to the discussion of fundamental problems of radiation physics and its technical applications. The first nine conferences were held four times in Tomsk, then in Ulan-Ude (Russia), Bishkek (Kyrgyzstan), Tashkent (Uzbekistan), Sharm El Sheikh (Egypt), and the island of Cyprus. The tenth conference was held in Tomsk, Russia. The program of the Conference covers a wide range of technical areas and modern aspects of radiation physics, its applications and related matters. Topics of interest include, but are not limited to: • Physical and chemical phenomena in inorganic materials in radiation, electrical and thermal fields; • Research methods and equipment modification states and properties of materials; • Technologies and equipment for their implementation; • The use of radiation-thermal processes in nanotechnology; • Adjacent to the main theme of the conference issues The conference was attended by leading scientists from countries near and far abroad who work in the field of radiation physics of solid state and of radiation material science. The School-Conference of Young Scientists was held during the conference. The event was held with the financial support of the Russian Foundation for Basic Research, projects No. 14-38-10210 and No. 14-02-20376.

  8. JOURNAL OF MATERIALS SCIENCE LETTERS 21, 2002, 251 255 Organic-inorganic sol-gel coating for corrosion protection

    E-print Network

    Cao, Guozhong

    for corrosion protection of stainless steel T. P. CHOU Department of Materials Science and EngineeringJOURNAL OF MATERIALS SCIENCE LETTERS 21, 2002, 251­ 255 Organic-inorganic sol-gel coating, Redmond, WA, USA S. LIMMER, C. NGUYEN, G. Z. CAO Department of Materials Science and Engineering

  9. Self-aligned optical couplings by self-organized waveguides toward luminescent targets in organic/inorganic hybrid materials.

    PubMed

    Yoshimura, Tetsuzo; Iida, Makoto; Nawata, Hideyuki

    2014-06-15

    Self-organization of optical waveguides is observed between two opposed optical fibers placed in a photosensitive organic/inorganic hybrid material, Sunconnect. A luminescent target containing coumarin 481 was deposited onto the edge of one of the two fibers at the core. When a 448-nm write beam was introduced from the other fiber, the write beam and the luminescence from the photoexcited target increased the refractive index of Sunconnect to induce self-focusing. Traces of waveguides were seen to grow from the cores of both fibers and merged into a single self-aligned optical coupling between the fibers. This optical solder functionality enabled increases in both coupling efficiency and tolerance to lateral misalignment of the fibers. PMID:24978520

  10. Functional role of inorganic trace elements in angiogenesis-Part I: N, Fe, Se, P, Au, and Ca.

    PubMed

    Saghiri, Mohammad Ali; Asatourian, Armen; Orangi, Jafar; Sorenson, Christine M; Sheibani, Nader

    2015-10-01

    Many inorganic elements are recognized as being essential for the growth of all living organisms. Transfer of nutrients and waste material from cells and tissues in the biological systems are accomplished through a functional vasculature network. Maintenance of the vascular system is vital to the wellbeing of organisms, and its alterations contribute to pathogenesis of many diseases. This article is the first part of a review on the functional role of inorganic elements including nitrogen, iron, selenium, phosphorus, gold, and calcium in angiogenesis. The methods of exposure, structure, mechanisms, and potential activity of these elements are briefly summarized. An electronic search was performed on the role of these elements in angiogenesis from January 2005 to April 2014. The recent aspects of the relationship between different elements and their role in angiogenesis, and production of pro- and anti-angiogenic factors were assessed. Several studies emphasized the role of these elements on the different phases of angiogenesis process in vivo. These elements can either enhance or inhibit angiogenesis events. Nitrogen in combination with bisphosphonates has antiangiogenic effects, while nitric oxide promotes the production of angiogenic growth factors. Iron deficiency can stimulate angiogenesis, but its excess suppresses angiogenesis events. Gold nanoparticles and selenium agents have therapeutic effects due to their anti-angiogenic characteristics, while phosphorus and calcium ions are regarded as pro-angiogenic elements. Understanding how these elements impact angiogenesis may provide new strategies for treatment of many diseases with neovascular component. PMID:26088454

  11. Selective crystallization with preferred lithium-ion storage capability of inorganic materials

    PubMed Central

    2012-01-01

    Lithium-ion batteries are supposed to be a key method to make a more efficient use of energy. In the past decade, nanostructured electrode materials have been extensively studied and have presented the opportunity to achieve superior performance for the next-generation batteries which require higher energy and power densities and longer cycle life. In this article, we reviewed recent research activities on selective crystallization of inorganic materials into nanostructured electrodes for lithium-ion batteries and discuss how selective crystallization can improve the electrode performance of materials; for example, selective exposure of surfaces normal to the ionic diffusion paths can greatly enhance the ion conductivity of insertion-type materials; crystallization of alloying-type materials into nanowire arrays has proven to be a good solution to the electrode pulverization problem; and constructing conversion-type materials into hollow structures is an effective approach to buffer the volume variation during cycling. The major goal of this review is to demonstrate the importance of crystallization in energy storage applications. PMID:22353373

  12. Electrohydrodynamic Patterning of Functional Materials

    E-print Network

    Goldberg Oppenheimer, Pola

    2014-05-27

    to Advanced Functional Materials, 2011. 5. Carbon Nanotubes Alignment via Electrohydrodynamic Patterning of Nanocom- posites. Goldberg Oppenheimer, P., Eder, D. and Steiner, U. Advanced Func- tional Materials, 21(10): 1895-1901, 2011. 6. Rapid... .3.3 Current Monitoring of the Rapid EHL Process . . . . . . . . . . 58 4.3.4 Variation of the Instability Time Constant with the Viscosity . 60 4.4 Conclusions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 62 5 Alignment of Carbon Nanotubes...

  13. Theoretical prediction and experimental realization of new stable inorganic materials using the inverse design approach.

    PubMed

    Zakutayev, Andriy; Zhang, Xiuwen; Nagaraja, Arpun; Yu, Liping; Lany, Stephan; Mason, Thomas O; Ginley, David S; Zunger, Alex

    2013-07-10

    Discovery of new materials is important for all fields of chemistry. Yet, existing compilations of all known ternary inorganic solids still miss many possible combinations. Here, we present an example of accelerated discovery of the missing materials using the inverse design approach, which couples predictive first-principles theoretical calculations with combinatorial and traditional experimental synthesis and characterization. The compounds in focus belong to the equiatomic (1:1:1) ABX family of ternary materials with 18 valence electrons per formula unit. Of the 45 possible V-IX-IV compounds, 29 are missing. Theoretical screening of their thermodynamic stability revealed eight new stable 1:1:1 compounds, including TaCoSn. Experimental synthesis of TaCoSn, the first ternary in the Ta-Co-Sn system, confirmed its predicted zincblende-derived crystal structure. These results demonstrate how discovery of new materials can be accelerated by the combination of high-throughput theoretical and experimental methods. Despite being made of three metallic elements, TaCoSn is predicted and explained to be a semiconductor. The band gap of this material is difficult to measure experimentally, probably due to a high concentration of interstitial cobalt defects. PMID:23672376

  14. Inorganic compounds for passive solar energy storage: Solid-state dehydration materials and high specific heat materials

    NASA Astrophysics Data System (ADS)

    Struble, L. J.; Brown, P. W.

    1986-04-01

    Two classes of hydrated inorganic salts have been studied to assess their potential as materials for passive solar energy storage. The materials are part of the quaternary system CaO-Al2O3-SO3-H2O and related chemical systems, and the two classes are typified by ettringite, a trisubstituted salt, and Friedel's salt, a monosubstituted salt. The trisubstituted salts were studied for their possible application in latent heat storage, utilizing a low-temperature dehydration reaction, and both classes were studies for their application in sensible heat storage. In order to assess their potential for energy storage, the salts have been synthesized, characterized by several analytical techniques, and thermal properties measured. The dehydration data of that the trisubstituted salts vary somewhat with chemical composition, with the temperature of the onset of dehydration ranging from 6(0)C to 33(0)C, and enthalpy changes on dehydration ranging from 60 to 200 cal/g. Heat capacity is less variable with composition; values for the trisubstituted phases are 30 cal/g/(0)C and for the monosubstituted phases between 0.23 and 0.28 cal/g/(0)C. Preliminary experiments indicate that the dehydration is reversible, and suggest that the materials might have additional potential as solar desiccant materials. These thermal data demonstrate the trisubstituted salts have potential as latent heat storage materials, and that both classes of salts have potential as sensible heat storage materials.

  15. a Comparative Study of Laser Cleaning of Archaeological Inorganic Materials with Traditional Methods

    NASA Astrophysics Data System (ADS)

    Imam, Hisham; Elsayed, Khaled; Madkour, Fatma

    2011-06-01

    Ancient artifacts excavated from archaeological site were covered with different soil contaminates and stains which changed their chemical composition and aesthetic appearance. Ancient inorganic materials such as bronze, glass and pottery covered with different contaminates such as corrosion products, soil deposits, organic stains and gray white encrustations. Lasers are currently being tested for a wide range of conservation applications. Since they are highly controllable and can be selectively applied, lasers can be used to achieve more effective and safer cleaning of archaeological artifacts and protect their surface details. In the present work we investigated in a general way the laser cleaning of bronze corrosion products, glass, and pottery by Q-switched Nd:YAG Lasers. The results were compared with conventional methods. The artifact samples were examined by Light Optical Microscope (LOM) and showed no noticeable damage.

  16. Synthesis of organic-inorganic hybrid azobenzene materials for the preparation of nanofibers by electrospinning

    NASA Astrophysics Data System (ADS)

    Bu?ko, Aleksandra; Zieli?ska, Sonia; Ortyl, Ewelina; Larkowska, Maria; Barille, Regis

    2014-12-01

    The new photochromic hybrid materials containing different mole fractions of highly photoactive 4-[(E)-[4-[ethyl(2-hydroxyethyl)amino]phenyl]azo]-N-(4-methylpyrimidin-2-yl)benzenesulfonamide (SMERe) were prepared by a low temperature sol-gel process. The guest-host systems with triethoxyphenylsilane matrix were obtained. These materials were used to form thin transparent films by a spin-coating technique. Then the ability of thin hybrid films to reversible trans-cis photoisomerization under illumination was investigated using ellipsometry and UV-Vis spectroscopy. The reversible changes of refractive index of the films under illumination were in the range of 0.005-0.056. The maximum absorption of these materials was located at 462-486 nm. Moreover, the organic-inorganic azobenzene materials were used to form nanofibers by electrospinning using various parameters of the process. The microstructure of electrospun fibers depended on sols properties (e.g. concentration and viscosity of the sols) and process conditions (e.g. the applied voltage, temperature or type of the collector) at ambient conditions. The morphology of obtained nanofibers was analyzed by an optical microscopy and scanning electron microscopy. In most instances, the beadless fibers were obtained. The wettability of the surface of electrospun fibers deposited on glass substrates was investigated.

  17. Styrene degradation by Pseudomonas sp. SR-5 in biofilters with organic and inorganic packing materials.

    PubMed

    Jang, J H; Hirai, M; Shoda, M

    2004-08-01

    Pseudomonas sp. SR-5 was isolated as a styrene-degrading bacterium. In liquid culture containing 1% (v/v) styrene, more than 90% styrene was degraded in 53 h and the doubling time of SR-5 was 2 h. The removal of styrene gas was investigated in biofilters for 31 days using an organic packing material of peat and an inorganic packing material of ceramic inoculated with SR-5. The maximum-styrene-elimination capacities for peat and ceramic packing materials were 236 and 81 g m(-3) h(-1), respectively. The percentage of styrene converted to low molecular weight compounds including CO(2) in the peat and ceramic biofilters during a 10-day operation were estimated to be 90.4 and 36.7%, respectively. As the pressure drop in the peat bioflter at the end of experiment was significantly higher than that in ceramic biofilter, a biofilter using a mixture of peat and ceramic was tested. We determined that the maximum elimination capacity was 170 g m(-3) h(-1) and the production of low molecular weight compounds was 95% at a low pressure drop for this mixed packing material filter. PMID:15138732

  18. An intuitive thermal-induced surface zwitterionization for versatile, well-controlled haemocompatible organic and inorganic materials.

    PubMed

    Sin, Mei-Chan; Lou, Pei-Tzu; Cho, Chia-He; Chinnathambi, Arunachalam; Alharbi, Sulaiman Ali; Chang, Yung

    2015-03-01

    In this study, a facile and effective strategy is presented for the preparation of a series of zwitterionic poly(sulfobetaine methacrylate) (pSBMA)-grafted organic and inorganic biomaterials with well-controlled haemocompatibility via intuitive thermal-induced graft polymerization. The research focused on the effects of zwitterionic surface packing density on human blood compatibility by varying the SBMA monomer concentration on the silanized silicon wafer substrates. A 0.2 M SBMA monomer solution was found to not only produce Si wafer surfaces with ideal zwitterionic surface packing density and uniform, evenly distributed pSBMA grafting coverage but also yield optimal hydrophilicity and haemocompatibility. SBMA monomer concentrations lower and greater than 0.2 M yielded a zwitterionic surface with low grafting coverage. This study also demonstrated that the same, intuitive thermal-induced graft polymerization strategy could be applied to a variety of organic polymeric, inorganic ceramic and metal oxide biomaterials to improve haemocompatibility. Among the tested organic and inorganic materials, however, it was found that inorganic biomaterials demonstrated greater resistance to protein and platelet adhesions. It was hypothesized that the ozone treatment, which generated an abundance of hydroxide groups on inorganic substrate interfaces, might have given the inorganic biomaterials a more stable silanized layer yielding a preferable reaction state and resulted in sturdier and more durable pSBMA grafting. PMID:25638723

  19. Rapid Analysis of Inorganic Species in Herbaceous Materials Using Laser-Induced Breakdown Spectroscopy

    PubMed Central

    Emerson, Rachel M.

    2015-01-01

    Abstract Inorganic compounds in biomass, often referred to as ash, are known to be problematic in the thermochemical conversion of biomass to bio-oil or syngas and, ultimately, hydrocarbon fuels because they negatively influence reaction pathways, contribute to fouling and corrosion, poison catalysts, and impact waste streams. The most common ash-analysis methods, such as inductively coupled plasma-optical emission spectrometry/mass spectrometry (ICP-OES/MS), require considerable time and expensive reagents. Laser-induced breakdown spectroscopy (LIBS) is emerging as a technique for rapid analysis of the inorganic constituents in a wide range of biomass materials. This study compares analytical results using LIBS data to results obtained from three separate ICP-OES/MS methods for 12 samples, including six standard reference materials. Analyzed elements include aluminum, calcium, iron, magnesium, manganese, phosphorus, potassium, sodium, and silicon, and results show that concentrations can be measured with an uncertainty of approximately 100 parts per million using univariate calibration models and relatively few calibration samples. These results indicate that the accuracy of LIBS is comparable to that of ICP-OES methods and indicate that some acid-digestion methods for ICP-OES may not be reliable for Na and Al. These results also demonstrate that germanium can be used as an internal standard to improve the reliability and accuracy of measuring many elements of interest, and that LIBS can be used for rapid determination of total ash in biomass samples. Key benefits of LIBS include little sample preparation, no reagent consumption, and the generation of meaningful analytical data instantaneously.

  20. Structure and magnetic properties of SiO{sub 2}/PCL novel sol–gel organic–inorganic hybrid materials

    SciTech Connect

    Catauro, Michelina; Bollino, Flavia; Cristina Mozzati, Maria; Ferrara, Chiara; Mustarelli, Piercarlo

    2013-07-15

    Organic–inorganic nanocomposite materials have been synthesized via sol–gel. They consist of an inorganic SiO{sub 2} matrix, in which different percentages of poly(?-caprolactone) (PCL) have been incorporated. The formation of H-bonds among the carbonyl groups of the polymer chains and Si–OH group of the inorganic matrix has been proved by means of Fourier transform infrared spectroscopy (FT-IR) analysis and has been confirmed by solid-state nuclear magnetic resonance (NMR). X-Ray diffraction (XRD) analysis highlighted the amorphous nature of the synthesized materials. Scanning electron microscope (SEM) micrograph and atomic force microscope (AFM) topography showed their homogeneous morphology and nanostructure nature. Considering the opportunity to synthesize these hybrid materials under microgravity conditions by means of magnetic levitation, superconducting quantum interference device (SQUID) magnetometry has been used to quantify their magnetic susceptibility. This measure has shown that the SiO{sub 2}/PCL hybrid materials are diamagnetic and that their diamagnetic susceptibility is independent of temperature and increases with the PCL amount. - Graphical abstract: Characterization and magnetic properties of SiO{sub 2}/PCL organic–inorganic hybrid materials synthesized via sol–gel. FT-IR, Fourier transform infrared spectroscopy; solid-state NMR: solid-state nuclear magnetic resonance; SQUID: superconducting quantum interference device. - Highlights: • Sol–gel synthesis of SiO{sub 2}/PCL amorphous class I organic–inorganic hybrid materials. • FT-IR and NMR analyses show the hydrogen bonds formation between SiO{sub 2} and PCL. • AFM and SEM analyses confirm that the SiO{sub 2}/PCL are homogenous hybrid materials. • The SQUID measures show that the simples are diamagnetic. • Diamagnetic susceptibility of SiO{sub 2}/PCL materials increases with the PCL amount.

  1. Solution Phase Routes to Functional Nanostructured Materials for Energy Applications

    NASA Astrophysics Data System (ADS)

    Rauda, Iris Ester

    Solution-phase processing presents an attractive avenue for building unique architectures from a wide variety of materials that exhibit functional properties, making them ideal candidates for various energy applications. The most basic building block or precursor in solution-based syntheses is a soluble species that can either self-assemble, or coassemble with a structure directing agent or template, to create a unique architecture. Soluble inorganic-based building blocks ranging from atomic-scale charged molecular complexes to nanometer-scale preformed nanocrystals are utilized to construct functional inorganic materials. These nanostructured materials are excellent candidates for integrating into electronic and energy-storage devices, including photovoltaics and pseudocapacitors. The goal of this work is to create inorganic nanostructured materials from solution-based methods. This work is divided into two parts: the first involves the synthesis of inorganic semiconductor-based nanostructured materials; the second focuses on developing porous metal oxide-based pseudocapacitors. The first part describes three distinct synthetic approaches to nanostructured semiconductors: the synthesis of complex metal chalcogenide semiconductors produced from highly soluble hydrazinium-based precursors using a porous template; low-temperature melt processing of an organic-inorganic hybrid semiconductor into porous templates to produce vertically-aligned arrays with a concentric multilayered structure; and solution-phase assembly of semiconductor nanocrystals of CdSe into nanoporous architectures via polymer templating. These nanostructured semiconductors are electrically interconnected through intimate contact between the molecular or nanoscale precursors achieved during solution-phase synthesis, making them suitable for a range of applications. In the second part, porous metal-oxide based materials are constructed by the assembly of nanosized building blocks into 3D porous architectures via polymer templating. Two main approaches are described: first, a general route for templating both redox-active oxides (Mn3O4, MnFe2O4) and conducting indium tin oxide (ITO) nanocrystals is described; second, nanocrystal-based porous architectures of a ITO are coated with redox-active V2O5 via atomic layer deposition to produce nanoporous composites. The porous architectures exhibit high surface areas, providing ample redox active sites, and an interconnected open porosity, facilitating solvent/ion diffusion to those sites. In the ITO-V2O 5 composites, the electron-transfer reactions are facilitated by the increased conductivity leading to high pseudocapacitive contributions to charge storage that are accompanied by fast charging/discharging rates.

  2. An empirically derived inorganic sea spray source function incorporating sea surface temperature

    NASA Astrophysics Data System (ADS)

    Salter, M. E.; Zieger, P.; Acosta Navarro, J. C.; Grythe, H.; Kirkevåg, A.; Rosati, B.; Riipinen, I.; Nilsson, E. D.

    2015-10-01

    We have developed an inorganic sea spray source function that is based upon state-of-the-art measurements of sea spray aerosol production using a temperature-controlled plunging jet sea spray aerosol chamber. The size-resolved particle production was measured between 0.01 and 10 ?m dry diameter. Particle production decreased non-linearly with increasing seawater temperature (between -1 and 30 °C) similar to previous findings. In addition, we observed that the particle effective radius, as well as the particle surface, particle volume and particle mass, increased with increasing seawater temperature due to increased production of particles with dry diameters greater than 1 ?m. By combining these measurements with the volume of air entrained by the plunging jet we have determined the size-resolved particle flux as a function of air entrainment. Through the use of existing parameterisations of air entrainment as a function of wind speed, we were subsequently able to scale our laboratory measurements of particle production to wind speed. By scaling in this way we avoid some of the difficulties associated with defining the "white area" of the laboratory whitecap - a contentious issue when relating laboratory measurements of particle production to oceanic whitecaps using the more frequently applied whitecap method. The here-derived inorganic sea spray source function was implemented in a Lagrangian particle dispersion model (FLEXPART - FLEXible PARTicle dispersion model). An estimated annual global flux of inorganic sea spray aerosol of 5.9 ± 0.2 Pg yr-1 was derived that is close to the median of estimates from the same model using a wide range of existing sea spray source functions. When using the source function derived here, the model also showed good skill in predicting measurements of Na+ concentration at a number of field sites further underlining the validity of our source function. In a final step, the sensitivity of a large-scale model (NorESM - the Norwegian Earth System Model) to our new source function was tested. Compared to the previously implemented parameterisation, a clear decrease of sea spray aerosol number flux and increase in aerosol residence time was observed, especially over the Southern Ocean. At the same time an increase in aerosol optical depth due to an increase in the number of particles with optically relevant sizes was found. That there were noticeable regional differences may have important implications for aerosol optical properties and number concentrations, subsequently also affecting the indirect radiative forcing by non-sea spray anthropogenic aerosols.

  3. An ultrafast nickel-iron battery from strongly coupled inorganic nanoparticle/nanocarbon hybrid materials.

    PubMed

    Wang, Hailiang; Liang, Yongye; Gong, Ming; Li, Yanguang; Chang, Wesley; Mefford, Tyler; Zhou, Jigang; Wang, Jian; Regier, Tom; Wei, Fei; Dai, Hongjie

    2012-01-01

    Ultrafast rechargeable batteries made from low-cost and abundant electrode materials operating in safe aqueous electrolytes could be attractive for electrochemical energy storage. If both high specific power and energy are achieved, such batteries would be useful for power quality applications such as to assist propelling electric vehicles that require fast acceleration and intense braking. Here we develop a new type of Ni-Fe battery by employing novel inorganic nanoparticle/graphitic nanocarbon (carbon nanotubes and graphene) hybrid materials as electrode materials. We successfully increase the charging and discharging rates by nearly 1,000-fold over traditional Ni-Fe batteries while attaining high energy density. The ultrafast Ni-Fe battery can be charged in ~2 min and discharged within 30 s to deliver a specific energy of 120 Wh kg(-1) and a specific power of 15 kW kg(-1). These features suggest a new generation of Ni-Fe batteries as novel devices for electrochemical energy storage. PMID:22735445

  4. Effect of exposure test conditions on leaching behavior of inorganic contaminants from recycled materials for roadbeds

    SciTech Connect

    Sakanakura, Hirofumi Osako, Masahiro; Kida, Akiko

    2009-05-15

    Throughout the utilization of recycled materials, weathering factors such as humidity, gas composition and temperature have the potential to change the material properties and enhance the release of inorganic contaminants. In this research, the effects of weathering factors on recycled gravel materials for roadbeds were evaluated by applying three kinds of accelerating exposure tests: freezing-melting cycle test, carbonation test, and dry-humid cycle test. The effects of exposure tests were determined by X-ray diffraction (XRD) analysis and serial batch leaching test, making it possible to identify the change in release mechanisms. Sixteen elements, mainly metals, were investigated. Tested samples were molten slag from municipal solid waste, molten slag from automobile shredded residue, and crushed natural stone. After the exposure tests, the increase of cumulative release in the leaching test was generally less than 2.0 times that of the samples without the exposure test. Among the three test conditions, freezing-melting showed a slightly higher effect of enhancing the release of constituents. XRD analysis showed no change in chemical species. From these results, it was determined that the stony samples were stable enough so that their properties were not significantly changed by the exposure tests.

  5. Organic and inorganic hazardous waste stabilization utilizing fossil fuel combustion waste materials

    SciTech Connect

    Netzel, D.A.; Lane, D.C.; Brown, M.A.; Raska, K.A.; Clark, J.A.; Rovani, J.F.

    1993-09-01

    A laboratory study was conducted at the Western Research Institute to evaluate the ability of innovative clean coal technology (ICCT) waste to stabilize organic and inorganic constituents of hazardous wastes. The four ICCT wastes used in this study were: (1) the Tennessee Valley Authority (TVA) atmospheric fluidized bed combustor (AFBC) waste, (2) the TVA spray dryer waste, (3) the Laramie River Station spray dryer waste, and (4) the Colorado-Ute AFBC waste. Four types of hazardous waste stream materials were obtained and chemically characterized for use in evaluating the ability of the ICCT wastes to stabilize hazardous organic and inorganic wastes. The wastes included an API separator sludge, mixed metal oxide-hydroxide waste, metal-plating sludge, and creosote-contaminated soil. The API separator sludge and creosote-contaminated soil are US Environmental Protection Agency (EPA)-listed hazardous wastes and contain organic contaminants. The mixed metal oxide-hydroxide waste and metal-plating sludge (also an EPA-listed waste) contain high concentrations of heavy metals. The mixed metal oxide-hydroxide waste fails the Toxicity Characteristic Leaching Procedure (TCLP) for cadmium, and the metal-plating sludge fails the TCLP for chromium. To evaluate the ability of the ICCT wastes to stabilize the hazardous wastes, mixtures involving varying amounts of each of the ICCT wastes with each of the hazardous wastes were prepared, allowed to equilibrate, and then leached with deionized, distilled water. The leachates were analyzed for the hazardous constituent(s) of interest using the Toxicity Characteristic Leaching Procedure.

  6. Crystallization behavior of PA6/SiO{sub 2} organic-inorganic hybrid material

    SciTech Connect

    Wang Hualin; Shi Tiejun . E-mail: stjdean@hfut.edu.cn; Yang Shanzhong; Hang Guopei

    2006-02-02

    Poly 2-hydroxy propylmethacrylate-methyl methacrylate/SiO{sub 2} (PHPMA-MMA/SiO{sub 2}), an active composite was used to synthesize polyamide-6/SiO{sub 2} (PA6/SiO{sub 2}) organic-inorganic hybrid materials via blending method. X-ray diffraction analysis (XRD) results showed that the addition of PHPMA-MMA/SiO{sub 2} composite induced PA6 to transit from {alpha} to {gamma} crystal form. The nonisothermal crystallization kinetics of PA6 and PA6/SiO{sub 2} hybrid materials was investigated by differential scanning calorimetry (DSC). Jeziorny method derived from Avrami analysis and a method developed by Liu were employed to describe the nonisothermal crystallization process of PA6 and PA6/SiO{sub 2} hybrid materials. Based on our experimental data, if the relative degree of crystallinity was approximately 60% or more, the Jeziorny method was not valid to describe the nonisothermal crystallization process, while Liu method was successful to describe the whole nonisothermal crystallization process. When X(t) was below about 60%, the crystallization rates of PA6 and PA6/SiO{sub 2} hybrid materials were very approximate, but when X(t) was approximately 60% or more, the crystallization rate of PA6 was quicker than that of PA6/SiO{sub 2} hybrid materials. Moreover, the addition of PHPMA-MMA/SiO{sub 2} composite decreased the crystallization activation energy {delta}E calculated by Kissinger equation because of the {gamma} transition.

  7. Litter ammonia generation: moisture content and organic versus inorganic bedding materials.

    PubMed

    Miles, D M; Rowe, D E; Cathcart, T C

    2011-06-01

    Negative impacts on the environment, bird well-being, and farm worker health indicate the need for abatement strategies for poultry litter NH(3) generation. Type of bedding affects many parameters related to poultry production including NH(3) losses. In a randomized complete block design, 3 trials compared the cumulative NH(3) volatilization for laboratory-prepared litter (4 bedding types mixed with excreta) and commercial litter (sampled from a broiler house during the second flock on reused pine wood chips). Litters were assessed at the original moisture content and 2 higher moisture contents. Broiler excrement was mixed with pine wood shavings, rice hulls, sand, and vermiculite to create litter samples. Volumetrically uniform litter samples were placed in chambers receiving humidified air where the exhaust passed through H(3)BO(3) solution, trapping litter-emitted NH(3). At the original moisture content, sand and vermiculite litters generated the most NH(3) (5.3 and 9.1 mg of N, respectively) whereas wood shavings, commercial, and rice hull litters emitted the least NH(3) (0.9-2.6 mg of N). For reducing NH(3) emissions, the results support recommendations for using wood shavings and rice hulls, already popular bedding choices in the United States and worldwide. In this research, the organic bedding materials generated the least NH(3) at the original moisture content when compared with the inorganic materials. For each bedding type, incremental increases in litter moisture content increased NH(3) volatilization. However, the effects of bedding material on NH(3) volatilization at the increased moisture levels were not clearly differentiated across the treatments. Vermiculite generated the most NH(3) (26.3 mg of N) at the highest moisture content. Vermiculite was a novel bedding choice that has a high water absorption capacity, but because of high NH(3) generation, it is not recommended for further study as broiler bedding material. Controlling unnecessary moisture inputs to broiler litter is a key to controlling NH(3) emissions. PMID:21597054

  8. Surface energy induced patterning of organic and inorganic materials on heterogeneous Si surfaces

    E-print Network

    Hu, Wenchuang "Walter"

    to transfer the resist patterns to the functional materials either by an etching or lift-off process.11 and imprinting techniques have posed limitations for the fabrication of functional polymer nanostructures on metal thin films under laser radiation.23,24 In addi- tion, applied electric field or capillary forces

  9. Oxidation control of fluxes for mixed-valent inorganic oxide materials synthesis

    NASA Astrophysics Data System (ADS)

    Schrier, Marc David

    This dissertation is concerned with controlling the flux synthesis and ensuing physical properties of mixed-valence metal oxides. Molten alkali metal nitrates and hydroxides have been explored to determine and exploit their variable redox chemistries for the synthesis of mixed-valent oxide materials. Cationic and anionic additives have been utilized in these molten salts to control the relative concentrations of the redox-active species present to effectively tune and cap the electrochemical potential of the flux. Atoms like bismuth, copper, and manganese are capable of providing different numbers of electrons for bonding. With appropriate doping near the metal-insulator transition, many of these mixed-valent inorganic metal oxides exhibit extraordinary electronic and magnetic properties. Traditionally, these materials have been prepared by classical high temperature solid state routes where microscopic homogeneity is hard to attain. In these routes, the starting composition dictates the doping level, and in turn, the formal oxidation state achieved. Molten flux syntheses developed in this work have provided the potential for preparing single-phase, homogeneous, and crystalline materials. The redox-active fluxes provide a medium for enhanced doping and mixed-valency control in which the electrochemical potential adjusts the formal oxidation state, and the doping takes place to maintain charge neutrality. The two superconductor systems investigated are: (1) the potassium-doped barium bismuth oxides, and (2) the alkali metal- and alkaline earth metal-doped lanthanum copper oxides. Controlled oxidative doping has been achieved in both systems by two different approaches. The superconducting properties of these materials have been assessed, and the materials have been characterized by powder X-ray diffraction and e-beam microprobe elemental analyses. In the course of these studies, several other materials have been identified. Analysis of these materials, and the conditions necessary to prepare them, have further aided in developing a model for use in controlling the electrochemical potential of the flux. The alkali metal hydroxide fluxes have large electrochemical windows, and a variety of chemical reducers have been explored in the copper system. Control of the electrochemical potential has been developed through compositional control of the flux whereby the entire range of copper oxidation states, including the metal, has been achieved at a single temperature, in a single flux system. Environmentally-friendly copper ore mimics have been prepared for thermodynamic analysis to aid in mineral transport modeling. The hydrothermally-prepared homogeneous copper- and cobalt-doped birnessites have been structurally, compositionally, and physically analyzed.

  10. One-step DGC assembly and structural characterization of a hairy particle zeolite-like organic-inorganic hybrid as an efficient modifiable catalytic material.

    PubMed

    Zhou, Dan; Xu, Jun; Deng, Jiejie; Wei, Xianlong; Lu, Xinhuan; Chu, Xing; Deng, Feng; Xia, Qinghua

    2015-09-01

    Organic-inorganic hybrid microporous crystalline molecular sieves, extending the application of conventional zeolites in the fields of selective catalysis and adsorption, have aroused great interest in chemists. However, the complicated and difficult synthesis of organic-inorganic hybrid microporous molecular sieves by using a conventional hydrothermal method has hindered the rapid development of this field. The present work describes the recent progress in the synthesis of a hairy particle zeolite-like organic-inorganic hybrid with the high organic group content by one-step dry-gel conversion (DGC) assembly of organic Si, inorganic Si and other inorganic species without any organic template, which is proven to be efficient, economical, simple, and controllable. Thus-synthesized hybrid materials, as we know, with the highest organic group content reported in the literature, can be bestowed with modifiable catalytic activities by different treatments. This study will be applicable for the development of organic-inorganic hybrid catalytic materials. PMID:26218297

  11. Design of hybrid conjugated polymer materials: 1) Novel inorganic/organic hybrid semiconductors and 2) Surface modification via grafting approaches

    NASA Astrophysics Data System (ADS)

    Peterson, Joseph J.

    The research presented in this dissertation focuses on the design and synthesis of novel hybrid conjugated polymer materials using two different approaches: (1) inorganic/organic hybrid semiconductors through the incorporation of carboranes into the polymer structure and (2) the modification of surfaces with conjugated polymers via grafting approaches. Hybrid conjugated polymeric materials, which are materials or systems in which conjugated polymers are chemically integrated with non-traditional structures or surfaces, have the potential to harness useful properties from both components of the material to help overcome hurdles in their practical realization in polymer-based devices. This work is centered around the synthetic challenges of creating new hybrid conjugated systems and their potential for advancing the field of polymer-based electronics through both greater understanding of the behavior of hybrid systems, and access to improved performance and new applications. Chapter 1 highlights the potential applications and advantages for these hybrid systems, and provides some historical perspective, along with relevant background materials, to illustrate the rationale behind this work. Chapter 2 explores the synthesis of poly(fluorene)s with pendant carborane cages. The Ni(0) dehalogenative polymerization of a dibromofluorene with pendant carborane cages tethered to the bridging 9-position produced hybrid polymers produced polymers which combined the useful emissive characteristics of poly(fluorene) with the thermal and chemical stability of carborane cages. The materials were found to display increased glass transition temperatures and showed improved emission color stability after annealing at high temperatures relative to the non-hybrid polymer. The design and synthesis of a poly(fluorene)-based hybrid material with carborane cages in the backbone, rather than as pendant groups, begins in chapter 3. Poly(fluorene) with p-carborane in the backbone is synthesized and characterized, and the material is found to be a high MW, soluble blue emitter which shows a higher glass transition temperature and greater stability than a non-hybrid polymer. UV absorbance and fluorescence spectroscopy indicated some electronic interaction between the conjugated polymer and the cages, but they did not appear to be fully conjugated in the traditional sense. Chapter 4 describes the design, synthesis, and characterization of poly(fluorene) with o-carborane in the backbone. Profound changes in the behavior of the polymer, from its polymerization behavior to its emission characteristics, were observed and their origins are discussed. Experiments to explore the nature of the cage/polymer interactions were performed and possible applications which take advantage of the unique nature of the o-carborane hybrid polymer are explored and discussed. Hybrid conjugated polymer materials via grafting approaches to surfaces and surface modification are discussed starting in chapter 5. The synthesis of a dibromofluorene-based silane coupling agent for the surface functionalization of oxide surfaces is presented, and the surface directed Ni(0) dehalogenative polymerization of poly(dihexylfluorene) is explored. Chapter 6 focuses on the exploration of conjugated polymer/cellulose hybrid materials. Surface medication of cellulose materials with monomer-like anchor points is discussed. Grafting of the modified cellulose with conjugated polymers was explored and the grafting of three different repeat structures based on fluorene-, fluorenevinylene-, and fluoreneethynylene motifs were optimized to provide a general route to cellulose/conjugated polymer hybrid materials. Characterization and possible applications of such hybrid materials are discussed. Finally, chapter 7 is devoted to the simultaneous surface patterning and functionalization of poly(2-hydroxyethylmethacrylate) thin films using a silane infusion-based wrinkling technique. While not a conjugated polymer system, the spontaneous patterning and functionalization methods explored in this chapter prod

  12. Numerical and Experimental Analysis on Inorganic Phase Change Material Usage in Construction

    NASA Astrophysics Data System (ADS)

    Muthuvel, S.; Saravanasankar, S.; Sudhakarapandian, R.; Muthukannan, M.

    2014-12-01

    This work demonstrates the significance of Phase Change Material (PCM) in the construction of working sheds and product storage magazines in fireworks industries to maintain less temperature variation by passive cooling. The inorganic PCM, namely Calcium Chloride Hexahydrate (CCH) is selected in this study. First, the performance of two models with inbuilt CCH was analysed, using computational fluid dynamics. A significant change in the variation of inner wall temperature was observed, particularly during the working hours. This is mainly due to passive cooling, where the heat transfer from the surroundings to the room is partially used for the phase change from solid to liquid. The experiment was carried out by constructing two models, one with PCM packed in hollow brick walls and roof, and the other one as a conventional construction. The experimental results show that the temperature of the room got significantly reduced up to 7 °C. The experimental analysis results had good agreement with the numerical analysis results, and this reveals the advantage of the PCM in the fireworks industry construction.

  13. [Development and evaluation of fertilizers cemented and coated with organic-inorganic materials].

    PubMed

    Xiao, Qiang; Wang, Jia-Chen; Zuo, Qiang; Zhang, Lin; Liu, Bao-Cun; Zhao, Tong-Ke; Zou, Guo-Yuan; Xu, Qiu-Ming

    2010-01-01

    Four kinds of organic-inorganic cementing and coating materials were prepared by a coating method using water as the solvent, and the corresponding cemented and coated fertilizers (B2, PS, F2, and F2F) were produced by disc pelletizer. The tests on the properties of these fertilizers showed that the granulation rate, compression strength, and film-forming rate were B2 > PS > F2 > F2F. Soil column leaching experiment showed that the curve of accumulated nitrogen-dissolving rate was the gentlest for B2. In 48 days, the accumulated nitrogen-dissolving rate was in the order of B2, 54.65% < PS, 56.16% < F2, 59.47%, < F2F, 63.12%. Field experiment showed that compared with the same application amount of NPK, all the test fertilizers had better effects on corn yield, among which, B2 was the best, with the corn yield and fertilizer use efficiency increased by 19.72% and 20.30%, respectively. The yield-increasing effect of other test fertilizers was in the order of PS > F2 > F2F. PMID:20387432

  14. Nano-Structured Bio-Inorganic Hybrid Material for High Performing Oxygen Reduction Catalyst.

    PubMed

    Jiang, Rongzhong; Tran, Dat T; McClure, Joshua P; Chu, Deryn

    2015-08-26

    In this study, we demonstrate a non-Pt nanostructured bioinorganic hybrid (BIH) catalyst for catalytic oxygen reduction in alkaline media. This catalyst was synthesized through biomaterial hemin, nanostructured Ag-Co alloy, and graphene nano platelets (GNP) by heat-treatment and ultrasonically processing. This hybrid catalyst has the advantages of the combined features of these bio and inorganic materials. A 10-fold improvement in catalytic activity (at 0.8 V vs RHE) is achieved in comparison of pure Ag nanoparticles (20-40 nm). The hybrid catalyst reaches 80% activity (at 0.8 V vs RHE) of the state-of-the-art catalyst (containing 40% Pt and 60% active carbon). Comparable catalytic stability for the hybrid catalyst with the Pt catalyst is observed by chronoamperometric experiment. The hybrid catalyst catalyzes 4-electron oxygen reduction to produce water with fast kinetic rate. The rate constant obtained from the hybrid catalyst (at 0.6 V vs RHE) is 4 times higher than that of pure Ag/GNP catalyst. A catalytic model is proposed to explain the oxygen reduction reaction at the BIH catalyst. PMID:26280984

  15. A combined remote Raman and fluorescence spectrometer system for detecting inorganic and biological materials

    NASA Astrophysics Data System (ADS)

    Sharma, Shiv K.; Misra, Anupam K.; Lucey, Paul G.

    2006-12-01

    We have developed a combined remote telescopic Raman and laser-induced native fluorescence (LINF) spectrograph with 532 nm pulsed laser excitation and a gated CCD detector. With this system, we have measured time-resolved Raman and LINF spectral measurements at 9 m with 10-ns time resolution. A comparison of Raman spectra of calcite crystal and that of chicken eggshell show that the CaCO 3 in the chicken eggshell is arranged in a calcite structure. The strong LINF band in the spectrum of the calcite crystal has lifetime longer than 1 ?s, whereas the lifetime of LINF bands of the eggshell are in 10's of nano-sec (ns). The time-resolved Raman spectra of tomato and poinsettia (Euphorbia pulcherrimum) green leaves show resonance Raman features of carotenes. The time-resolved remote LINF spectrum of ruby crystals, and LINF spectra of tomato and poinsettia green leaves yield information that the LINF lifetime of ruby lines is much longer (in milliseconds (ms)) as compared with the fluorescence lifetime of the tomato and the poinsettia leaves (in 10s of ns). These results show that it will be possible to discriminate between inorganic and biogenic materials on the basis of LINF lifetimes even with 8 nano-sec laser pulses and gated detection.

  16. Novel solar energy harvesting options based on solution-processable inorganic/organic hybrid materials

    NASA Astrophysics Data System (ADS)

    Stingelin, Natalie

    2015-03-01

    The growing demand for energy and increasing concerns for the effect of the excessive abuse of fossil fuels on the environment force the scientific world to search for alternative, clean and safe energy sources. Finding ways to harvest solar energy is thereby one of the most appealing options. Here, we present a novel approach that exploits the versatile properties of recently developed, photoactive organic/inorganic hybrid fluids based on titanium oxide hydrates and polyalcohols for the production of versatile solar fuels. We will show that such systems can absorb light in the UV-near visible wave-length range. The sunlight's energy is then converted into chemical energy in the form of reduced titanium species, which can be re-oxidised by oxygen when required. Therefore, the absorbed energy is stored as long as oxygen is excluded by the hybrid system. We, furthermore, demonstrate that once discharged, the fluid can be activated again by exposing it to sunlight and recycled - a property that is important technologically. The same hybrids can also be exploited to produce structures that permit efficient management of light. We will illustrate the potential of this class of materials based on some of our recent approaches to fabricate light-scattering and light in-coupling structures, and discuss future opportunities they open up.

  17. Activation and splitting of carbon dioxide on the surface of an inorganic electride material

    PubMed Central

    Toda, Yoshitake; Hirayama, Hiroyuki; Kuganathan, Navaratnarajah; Torrisi, Antonio; Sushko, Peter V.; Hosono, Hideo

    2013-01-01

    Activation of carbon dioxide is the most important step in its conversion into valuable chemicals. Surfaces of stable oxide with a low work function may be promising for this purpose. Here we report that the surfaces of the inorganic electride [Ca24Al28O64]4+(e?)4 activate and split carbon dioxide at room temperature. This behaviour is attributed to a high concentration of localized electrons in the near-surface region and a corrugation of the surface that can trap oxygen atoms and strained carbon monoxide and carbon dioxide molecules. The [Ca24Al28O64]4+(e?)4 surface exposed to carbon dioxide is studied using temperature-programmed desorption, and spectroscopic methods. The results of these measurements, corroborated with ab initio simulations, show that both carbon monoxide and carbon dioxide adsorb on the [Ca24Al28O64]4+(e?)4 surface at RT and above and adopt unusual configurations that result in desorption of molecular carbon monoxide and atomic oxygen upon heating. PMID:23986101

  18. Removal of Radioactive Nuclides by Multi-Functional Microcapsules Enclosing Inorganic Ion-Exchangers and Organic Extractants

    SciTech Connect

    Mimura, H.; Akiba, K.; Onodera, Y.

    2002-02-26

    The microcapsules enclosing two kinds of functional materials, inorganic ion-exchangers and organic extractants, were prepared by taking advantage of the high immobilization ability of alginate gel polymer. The fine powders of inorganic ion-exchanger and oil drops of extractant were kneaded with sodium alginate (NaALG) solution and the kneaded sol readily gelled in a salt solution of CaCl2, BaCl2 or HCl to form spherical gel particles. The uptake properties of various nuclides, 137Cs, 85Sr, 60Co, 88Y, 152Eu and 241Am, for thirty-four specimens of microcapsules in the presence of 10-1-10-4 M HNO3 were evaluated by the batch method. The distribution coefficient (Kd) of Cs+ above 103 cm3/g was obtained for the microcapsules enclosing CuFC or AMP. The Kd of Sr2+ around 102 cm3/g was obtained for the microcapsules containing clinoptilolite, antimonic acid, zeolite A, zeolite X or titanic acid. The microcapsules enclosing DEHPA exhibited relatively large Kd values of trivalent metal ions above 103 cm3/g; for example, the Kd values of Cs+, Sr2+, Co2+, Y3+, Eu3+ and Am3+ for a favorable microcapsule (CuFC/clinoptilolite/DEHPA/CaALG) were 1.1x104, 7.5x10, 1.1x10, 1.0x104, 1.4x104, 3.4x103 cm3/g, respectively. The uptake rates of Cs+, Y3+, Eu3+ and Am3+ for this microcapsule were rather fast; the uptake percentage above 90% was obtained after 19 h-shaking and the uptake equilibrium was attained within 1 d. The AMP/CaALG exhibited high uptake ability for Cs+ even after irradiation of 188 kGy, and DEHPA/CaALG microcapsule had similar Kd values of Cs+, Sr2+, Co2+, Y3+, Eu3+ and Am3+ ions before and after irradiation. The microcapsules with various shapes such as spherical, columnar, fibrous and filmy forms were easily prepared by changing the way of dipping kneaded sol into gelling salt solution. The microcapsules enclosing inorganic ion-exchangers and extractants have a potential possibility for the simultaneous removal of various radioactive nuclides from waste solutions.

  19. Microbial mediated retention/transformation of organic and inorganic materials in freshwater and marine ecosystems

    EPA Science Inventory

    Aquatic ecosystems are globally connected by hydrological and biogeochemical cycles. Microorganisms inhabiting aquatic ecosystems form the basis of food webs, mediate essential element cycles, decompose natural organic matter, transform inorganic nutrients and metals, and degrad...

  20. The Features of Self-Assembling Organic Bilayers Important to the Formation of Anisotropic Inorganic Materials in Microgravity Conditions

    NASA Technical Reports Server (NTRS)

    Talham, Daniel R.; Adair, James H.

    1999-01-01

    There is a growing need for inorganic anisotropic particles in a variety of materials science applications. Structural, optical, and electrical properties can be greatly augmented by the fabrication of composite materials with anisotropic microstructures or with anisotropic particles uniformly dispersed in an isotropic matrix. Examples include structural composites, magnetic and optical recording media, photographic film, certain metal and ceramic alloys, and display technologies including flat panel displays. While considerable progress has been made toward developing an understanding of the synthesis of powders composed of monodispersed, spherical particles, these efforts have not been transferred to the synthesis of anisotropic nanoparticles. The major objective of the program is to develop a fundamental understanding of the growth of anisotropic particles at organic templates, with emphasis on the chemical and structural aspects of layered organic assemblies that contribute to the formation of anisotropic inorganic particles.

  1. Functional materials for rechargeable batteries.

    PubMed

    Cheng, Fangyi; Liang, Jing; Tao, Zhanliang; Chen, Jun

    2011-04-19

    There is an ever-growing demand for rechargeable batteries with reversible and efficient electrochemical energy storage and conversion. Rechargeable batteries cover applications in many fields, which include portable electronic consumer devices, electric vehicles, and large-scale electricity storage in smart or intelligent grids. The performance of rechargeable batteries depends essentially on the thermodynamics and kinetics of the electrochemical reactions involved in the components (i.e., the anode, cathode, electrolyte, and separator) of the cells. During the past decade, extensive efforts have been dedicated to developing advanced batteries with large capacity, high energy and power density, high safety, long cycle life, fast response, and low cost. Here, recent progress in functional materials applied in the currently prevailing rechargeable lithium-ion, nickel-metal hydride, lead acid, vanadium redox flow, and sodium-sulfur batteries is reviewed. The focus is on research activities toward the ionic, atomic, or molecular diffusion and transport; electron transfer; surface/interface structure optimization; the regulation of the electrochemical reactions; and the key materials and devices for rechargeable batteries. PMID:21394791

  2. Bridging Adhesion of a Protein onto an Inorganic Surface Using Self-Assembled Dual-Functionalized Spheres.

    PubMed

    Sato, Sota; Ikemi, Masatoshi; Kikuchi, Takashi; Matsumura, Sachiko; Shiba, Kiyotaka; Fujita, Makoto

    2015-10-14

    For the bridging adhesion of different classes of materials in their intact functional states, the adhesion of biomolecules onto inorganic surfaces is a necessity. A new molecular design strategy for bridging adhesion was demonstrated by the introduction of two independent recognition groups on the periphery of spherical complexes self-assembled from metal ions (M) and bidentate ligands (L). These dual-functionalized M12L24 spheres were quantitatively synthesized in one step from two ligands, bearing either a biotin for streptavidin recognition or a titania-binding aptamer, and Pd(II) ions. The selective recognition of titania surfaces was achieved by ligands with hexapeptide aptamers (Arg-Lys-Leu-Pro-Asp-Ala: minTBP-1), whose fixation ability was enhanced by the accumulation effect on the surface of the M12L24 spheres. These well-defined spherical structures can be specifically tailored to promote interactions with both titania and streptavidin simultaneously without detrimentally affecting either recognition motif. The irreversible immobilization of the spheres onto titania was revealed quantitatively by quartz crystal microbalance measurements, and the adhesion of streptavidin to the titania surface mediated by the biotin surrounding the spheres was visually demonstrated by lithographic patterning experiments. PMID:26190770

  3. Exponentially Modified Gaussian Function. An Empirical Equation for Description of the Band Emission of Inorganic Phosphors

    NASA Astrophysics Data System (ADS)

    Nötzold, D.

    1997-09-01

    The empirically found, exponentially modified Gaussian function is used for the description of the band emission of inorganic phosphors. The function includes the two parameters, the intensity of the maximum (I0) and its spectral position (-0), and besides two parameters for the slope of the flanks of the emission band (k1, k2) and two parameters for their deviation from the true Gaussian distribution (n1, n2). The equation is applied to the emission spectra of centre phosphors and crystal phosphors doped by different activator ions and moreover of non-activated phosphors. Correlation coefficients are in the order of magnitude of 0.9999. The function also succeeded in splitting up emission bands into two bands. Die empirisch gefundene Gleichung ist eine exponentiell modifizierte Gauss-Funktion. Sie dient zur Beschreibung der Emissionsspektren von anorganischen Leuchtstoffen mit bandenf<>oeh<>rmiger Emission. Die Funktion enthält neben den beiden Parametern Maximumsintensität (I0) und Maximumslage (-0) für jeden der beiden Kurven<>aeh<>ste jeweils einen Parameter für seine Neigung (k1, k2) und jeweils einen für seine Abweichung von der Gauss-Verteilung (n1, n2). Die Gleichung wird auf die Emissionsspektren von Zentren- und Kristallphosphoren mit unterschiedlichen Aktivatoren sowie von Reinstoffluminophoren angewendet. Die Korrelationskoeffizienten liegen im Bereich von 0,9999. Die Funktion wird auch bei Bandentrennungen mit Erfolg eingesetzt.

  4. Interactions between cocoa flavanols and inorganic nitrate: additive effects on endothelial function at achievable dietary amounts.

    PubMed

    Rodriguez-Mateos, Ana; Hezel, Michael; Aydin, Hilal; Kelm, Malte; Lundberg, Jon O; Weitzberg, Eddie; Spencer, Jeremy P E; Heiss, Christian

    2015-03-01

    Dietary intervention studies have shown that flavanols and inorganic nitrate can improve vascular function, suggesting that these two bioactives may be responsible for beneficial health effects of diets rich in fruits and vegetables. We aimed to study interactions between cocoa flavanols (CF) and nitrate, focusing on absorption, bioavailability, excretion, and efficacy to increase endothelial function. In a double-blind randomized, dose-response crossover study, flow-mediated dilation (FMD) was measured in 15 healthy subjects before and at 1, 2, 3, and 4 h after consumption of CF (1.4-10.9 mg/kg bw) or nitrate (0.1-10 mg/kg bw). To study flavanol-nitrate interactions, an additional intervention trial was performed with nitrate and CF taken in sequence at low and high amounts. FMD was measured before (0 h) and at 1h after ingestion of nitrate (3 or 8.5 mg/kg bw) or water. Then subjects received a CF drink (2.7 or 10.9 mg/kg bw) or a micro- and macronutrient-matched CF-free drink. FMD was measured at 1, 2, and 4 h thereafter. Blood and urine samples were collected and assessed for CF and nitric oxide (NO) metabolites with HPLC and gas-phase reductive chemiluminescence. Finally, intragastric formation of NO after CF and nitrate consumption was investigated. Both CF and nitrate induced similar intake-dependent increases in FMD. Maximal values were achieved at 1 h postingestion and gradually decreased to reach baseline values at 4 h. These effects were additive at low intake levels, whereas CF did not further increase FMD after high nitrate intake. Nitrate did not affect flavanol absorption, bioavailability, or excretion, but CF enhanced nitrate-related gastric NO formation and attenuated the increase in plasma nitrite after nitrate intake. Both flavanols and inorganic nitrate can improve endothelial function in healthy subjects at intake amounts that are achievable with a normal diet. Even low dietary intake of these bioactives may exert relevant effects on endothelial function when ingested together. PMID:25530151

  5. Novel organic polymer-inorganic hybrid material zinc poly(styrene-phenylvinylphosphonate)-phosphate prepared with a simple method

    SciTech Connect

    Huang Jing; Fu Xiangkai; Wang Gang; Miao Qiang

    2011-09-15

    A novel type of organic polymer-inorganic hybrid material layered crystalline zinc poly(styrene-phenylvinylphosphonate)-phosphate (ZnPS-PVPP) was synthesized under mild conditions in the absence of any template. And the ZnPS-PVPP were characterized by FT-IR, diffusion reflection UV-vis, AAS, N{sub 2} volumetric adsorption, SEM, TEM and TG. Notably, this method was entirely different from the traditional means used for preparing other zinc phosphonate. Moreover, it could be deduced that ZnPS-PVPP possessed the potential applications for catalyst supports. In the initial catalytic tests, the catalysts immobilized onto ZnPS-PVPP showed comparable or higher activity and enantioselectivity with that of catalysts reported by our group in the asymmetric epoxidation of unfunctional olefins. - Graphical Abstract: Zinc poly(styrene-phenylvinylphosphonate)-phosphate was a novel type of layered crystalline organic polymer-inorganic hybrid material prepared under mild conditions without addition of any template and could be used as heterogeneous catalyst supports. Highlights: > New types of layered crystalline inorganic-organic polymer hybrid materials zinc poly(styrene-phenylvinylphosphonate-phosphate(ZnPS-PVPP)). > ZnPS-PVPP prepared under mild condition without adding of any template. > Immobilized chiral salen Mn (III) catalysts on ZnPS-PVPP supports show comparative activity and enantioselectivity with that of on ZSPP or ZPS-PVPA.

  6. Blood Pressure, Left Ventricular Geometry, and Systolic Function in Children Exposed to Inorganic Arsenic

    PubMed Central

    Osorio-Yáñez, Citlalli; Ayllon-Vergara, Julio C.; Arreola-Mendoza, Laura; Aguilar-Madrid, Guadalupe; Hernández-Castellanos, Erika; Sánchez-Peña, Luz C.

    2015-01-01

    Background: Inorganic arsenic (iAs) is a ubiquitous element present in the groundwater worldwide. Cardiovascular effects related to iAs exposure have been studied extensively in adult populations. Few epidemiological studies have been focused on iAs exposure–related cardiovascular disease in children. Objective: In this study we investigated the association between iAs exposure, blood pressure (BP), and functional and anatomical echocardiographic parameters in children. Methods: A cross-sectional study of 161 children between 3 and 8 years was conducted in Central Mexico. The total concentration of arsenic (As) species in urine (U-tAs) was determined by hydride generation–cryotrapping–atomic absorption spectrometry and lifetime iAs exposure was estimated by multiplying As concentrations measured in drinking water by the duration of water consumption in years (LAsE). BP was measured by standard protocols, and M-mode echocardiographic parameters were determined by ultrasonography. Results: U-tAs concentration and LAsE were significantly associated with diastolic (DBP) and systolic blood pressure (SBP) in multivariable linear regression models: DBP and SBP were 0.013 (95% CI: 0.002, 0.024) and 0.021 (95% CI: 0.004, 0.037) mmHg higher in association with each 1-ng/mL increase in U-tAs (p < 0.025), respectively. Left ventricular mass (LVM) was significantly associated with LAsE [5.5 g higher (95% CI: 0.65, 10.26) in children with LAsE > 620 compared with < 382 ?g/L-year; p = 0.03] in an adjusted multivariable model. The systolic function parameters left ventricular ejection fraction (EF) and shortening fraction were 3.67% (95% CI: –7.14, –0.20) and 3.41% (95% CI: –6.44, –0.37) lower, respectively, in children with U-tAs > 70 ng/mL compared with < 35 ng/mL. Conclusion: Early-life exposure to iAs was significantly associated with higher BP and LVM and with lower EF in our study population of Mexican children. Citation: Osorio-Yáñez C, Ayllon-Vergara JC, Arreola-Mendoza L, Aguilar-Madrid G, Hernández-Castellanos E, Sánchez-Peña LC, Del Razo LM. 2015. Blood pressure, left ventricular geometry, and systolic function in children exposed to inorganic arsenic. Environ Health Perspect 123:629–635;?http://dx.doi.org/10.1289/ehp.1307327 PMID:25738397

  7. Density functional theory studies of inorganic metallocene multidecker Vn(P6)n+1 (n=1-4) sandwich clusters

    NASA Astrophysics Data System (ADS)

    Wang, Jinlan; Zhang, Xiuyun; Schleyer, Paul von Ragué; Chen, Zhongfang

    2008-03-01

    Motivated by the synthesis of the first entirely inorganic metallocene sandwich ion [?5-Ti-(P5)2]2- [E. Urnezius et al. Science 295, 832 (2002)], we have designed a new inorganic metallocene sandwich [?6-V-(P6)2] and multidecker sandwich clusters up to V4(P6)5 by employing an all electron gradient-corrected density functional theory. The binding energies of the Vn(P6)n+1 complexes increase rapidly from half sandwich to the smallest full sandwich and become gradually afterwards. The highest occupied and lowest unoccupied molecular orbital gap and the vertical ionization energy decrease with increasing cluster size. The Vn(P6)n+1 clusters are nonferromagnetic and prefer the lowest available spin states. The smallest sandwich cluster, V(P6)2, has the high stability and might serve as a building block for one-dimensional inorganic polymers with high stabilities.

  8. Assessment of renal function of workers exposed to inorganic lead, cadmium or mercury vapor

    SciTech Connect

    Buchet, J.P.; Roels, H.; Bernard, A.; Lauwerys, R.

    1980-11-01

    The renal function of workers occupationally exposed to cadmium (n = 148), to mercury vapor (n = 63) or to inorganic lead (n = 25) has been compared with that of workers with no occupational exposure to heavy metals (n = 88). A moderate exposure to lead (Pb-B < 62 ..mu..g/100 ml) does not seem to alter renal function. Excessive exposure to cadmium increases the urinary excretion of both low- and high-molecular-weight proteins and of tubular enzymes. These changes are mainly observed in workers excreting more than 10 ..mu..g Cd/g creatinine or with Cd-B above 1 ..mu..g Cd/100 ml whole blood. Occupational exposure to mercury vapor induces glomerular dysfunction as evidenced by an increased urinary excretion of high-molecular-weight proteins and a slightly increased prevalence of higher ..beta../sub 2/-microglobulin concentration in plasma without concomitant change in urinary ..beta../sub 2/-microglobulin concentration. ..beta..-galactosidase activity in blood and in urine is also increased. The likelihood of these findings is greater in workers with Hg-B and Hg-U exceeding 3 ..mu..g/100 ml whole blood and 50 ..mu..g/g creatinine, respectively. The hypothesis is put forward that the glomerular dysfunction induced by cadmium and mercury might result from an autoimmune mechanism.

  9. Expression activation and functional analysis of HLA3, a putative inorganic carbon transporter in Chlamydomonas reinhardtii.

    PubMed

    Gao, Han; Wang, Yingjun; Fei, Xiaowen; Wright, David A; Spalding, Martin H

    2015-04-01

    The CO2 concentrating mechanism (CCM) is a key component of the carbon assimilation strategy of aquatic microalgae. Induced by limiting CO2 and tightly regulated, the CCM enables these microalgae to respond rapidly to varying environmental CO2 supplies and to perform photosynthetic CO2 assimilation in a cost-effective way. A functional CCM in eukaryotic algae requires Rubisco sequestration, rapid interconversion between CO2 and HCO3(-) catalyzed by carbonic anhydrases (CAs), and active inorganic carbon (Ci) uptake. In the model microalga Chlamydomonas reinhardtii, a membrane protein HLA3 is proposed to be involved in active Ci uptake across the plasma membrane. In this study, we use an artificially designed transcription activator-like effector (dTALE) to activate the expression of HLA3. The successful activation of HLA3 expression demonstrates dTALE as a promising tool for gene-specific activation and investigation of gene function in Chlamydomonas. Activation of HLA3 expression in high CO2 acclimated cells, where HLA3 is not expressed, resulted in increased Ci accumulation and Ci-dependent photosynthetic O2 evolution specifically in very low CO2 concentrations, which confirms that HLA3 is indeed involved in Ci uptake, and suggests it is mainly associated with HCO3(-) transport in very low CO2 concentrations, conditions in which active CO2 uptake is highly limited. PMID:25660294

  10. A new method for synthesizing fluid inclusions in fused silica capillaries containing organic and inorganic material

    NASA Astrophysics Data System (ADS)

    Chou, I.-Ming; Song, Yucai; Burruss, R. C.

    2008-11-01

    Considerable advances in our understanding of physicochemical properties of geological fluids and their roles in many geological processes have been achieved by the use of synthetic fluid inclusions. We have developed a new method to synthesize fluid inclusions containing organic and inorganic material in fused silica capillary tubing. We have used both round (0.3 mm OD and 0.05 or 0.1 mm ID) and square cross-section tubing (0.3 × 0.3 mm with 0.05 × 0.05 mm or 0.1 × 0.1 mm cavities). For microthermometric measurements in a USGS-type heating-cooling stage, sample capsules must be less than 25 mm in length. The square-sectioned capsules have the advantage of providing images without optical distortion. However, the maximum internal pressure ( P; about 100 MPa at 22 °C) and temperature ( T; about 500 °C) maintained by the square-sectioned capsules are less than those held by the round-sectioned capsules (about 300 MPa at room T, and T up to 650 °C). The fused silica capsules can be applied to a wide range of problems of interest in fluid inclusion and hydrothermal research, such as creating standards for the calibration of thermocouples in heating-cooling stages and frequency shifts in Raman spectrometers. The fused silica capsules can also be used as containers for hydrothermal reactions, especially for organic samples, including individual hydrocarbons, crude oils, and gases, such as cracking of C 18H 38 between 350 and 400 °C, isotopic exchanges between C 18H 38 and D 2O and between C 19D 40 and H 2O at similar temperatures. Results of these types of studies provide information on the kinetics of oil cracking and the changes of oil composition under thermal stress. When compared with synthesis of fluid inclusions formed by healing fractures in quartz or other minerals or by overgrowth of quartz at elevated P- T conditions, the new fused-silica method has the following advantages: (1) it is simple; (2) fluid inclusions without the presence of water can be formed; (3) synthesized inclusions are large and uniform, and they are able to tolerate high internal P; (4) it is suitable for the study of organic material; and (5) redox control is possible due to high permeability of the fused silica to hydrogen.

  11. A new method for synthesizing fluid inclusions in fused silica capillaries containing organic and inorganic material

    USGS Publications Warehouse

    Chou, I.-Ming; Song, Y.; Burruss, R.C.

    2008-01-01

    Considerable advances in our understanding of physicochemical properties of geological fluids and their roles in many geological processes have been achieved by the use of synthetic fluid inclusions. We have developed a new method to synthesize fluid inclusions containing organic and inorganic material in fused silica capillary tubing. We have used both round (0.3 mm OD and 0.05 or 0.1 mm ID) and square cross-section tubing (0.3 ?? 0.3 mm with 0.05 ?? 0.05 mm or 0.1 ?? 0.1 mm cavities). For microthermometric measurements in a USGS-type heating-cooling stage, sample capsules must be less than 25 mm in length. The square-sectioned capsules have the advantage of providing images without optical distortion. However, the maximum internal pressure (P; about 100 MPa at 22 ??C) and temperature (T; about 500 ??C) maintained by the square-sectioned capsules are less than those held by the round-sectioned capsules (about 300 MPa at room T, and T up to 650 ??C). The fused silica capsules can be applied to a wide range of problems of interest in fluid inclusion and hydrothermal research, such as creating standards for the calibration of thermocouples in heating-cooling stages and frequency shifts in Raman spectrometers. The fused silica capsules can also be used as containers for hydrothermal reactions, especially for organic samples, including individual hydrocarbons, crude oils, and gases, such as cracking of C18H38 between 350 and 400 ??C, isotopic exchanges between C18H38 and D2O and between C19D40 and H2O at similar temperatures. Results of these types of studies provide information on the kinetics of oil cracking and the changes of oil composition under thermal stress. When compared with synthesis of fluid inclusions formed by healing fractures in quartz or other minerals or by overgrowth of quartz at elevated P-T conditions, the new fused-silica method has the following advantages: (1) it is simple; (2) fluid inclusions without the presence of water can be formed; (3) synthesized inclusions are large and uniform, and they are able to tolerate high internal P; (4) it is suitable for the study of organic material; and (5) redox control is possible due to high permeability of the fused silica to hydrogen.

  12. Ecosustainable Development of Novel Bio-inorganic Hybrid Materials as UV Protection Systems for Potential Cosmetic Applications.

    PubMed

    Villa, Carla; Lacapra, Chiara; Rosa, Roberto; Veronesi, Paolo; Leonelli, Cristina

    2015-01-01

    A new organoclay, bio-inorganic hybrid material, was successfully prepared following the "green chemistry" principles, exploiting microwave irradiation (as an alternative energetic source) in both the solvent-free synthesis of the organic filler (UVB filter) and in its hydrothermal intercalation in a sodium Bentonite clay (renewable natural inorganic source at low temperature). The organic filler is a benzylidene camphor derivative with the same cationic moiety as the well- known UV filter camphor benzalkonium methosulfate. The aim of the research was the ecosustainable development of a new UV protection model, suitable for use in cosmetic and pharmaceutical products, with potential advantages of stability, efficiency and safety compared to the commercially available UVB sunscreens. The organically modified clay was thoroughly investigated using X-ray diffraction (XRD), infrared spectroscopy (IR), thermo gravimetric analysis and differential thermal analysis (DTA). Results confirmed the complete intercalation of the organic filler in the interlayer region of the smectite clay, leading to a new bio-inorganic hybrid material with potential for cosmetic and pharmaceutical applications in the UV protection field, as confirmed by preliminary photochemical studies. This work represents the first example in the use of Na-Bentonite cationic clay (usually employed as rheological additive) as hosting agent of the synthesized quaternary UVB filter, as well as in the complete MW-assisted preparation of the organoclay, starting from the synthesis of the organic UV sunscreen to its hydrothermal intercalation. PMID:26412223

  13. SolidSolid Phase Transformations in Inorganic Materials Edited by J. M. Howe, D. E. Laughlin, J. K. Lee, U. Dahmen and W. A. Soffa,

    E-print Network

    Cambridge, University of

    SolidSolid Phase Transformations in Inorganic Materials Edited by J. M. Howe, D. E. Laughlin, J. K. Lee, U. Dahmen and W. A. Soffa, TMS (The Minerals, Metals & Materials Society), 2005, Volume 1, pages 469­484 HARD BAINITE H. K. D. H. Bhadeshia University of Cambridge, Materials Science and Metallurgy

  14. Continuous spray forming of functionally gradient materials

    SciTech Connect

    McKechnie, T.N.; Richardson, E.H.; Watson, R.D.

    1995-12-31

    Researchers at Plasma Processes Inc. have produced a Functional Gradient Material (FGM) through advanced vacuum plasma spray processing for high heat flux applications. Outlined in this paper are the manufacturing methods used to develop a four component functional gradient material of copper, tungsten, boron, and boron nitride. The FGM was formed with continuous gradients and integral cooling channels eliminating bondlines and providing direct heat transfer from the high temperature exposed surface to a cooling medium. Metallurgical and X-ray diffraction analyses of the materials formed through innovative VPS processing are also presented. Applications for this functional gradient structural material range from fusion reactor plasma facing components to missile nose cones to boilers.

  15. Ceramic transactions: Functionally gradient materials. Volume 34

    SciTech Connect

    Holt, J.B.; Koizumi, Mitsue; Hirai, Toshio; Munir, Z.A.

    1993-01-01

    A functionally gradient material (FGM) is a composite that smoothly transitions from one material at one surface to another material at the opposite surface. Metals and ceramics are usually the materials that are combined in a controlled manner to optimize a specific property. The First International Symposium on Functionally Gradient Materials was held in Sendai, Japan, in August 1990. Contained in the present volume are the Proceedings of the Second International Symposium on Functionally Gradient Materials, presented at the Third International Ceramic Science and Technology Congress, held in San Francisco, CA, November 1-4, 1992. The papers presented here are divided into eight sections: the concept of FGM; mathematical modeling; methods of fabrication; material evaluation; applications; joining processes in FGM; process characterization; and design considerations. Separate abstracts are provided for each of the 54 papers.

  16. Two inorganic-organic hybrid materials based on polyoxometalate anions and methylene blue: Preparations, crystal structures and properties

    SciTech Connect

    Nie Shanshan; Zhang Yaobin; Liu Bin; Li Zuoxi; Hu Huaiming; Xue Ganglin; Fu Feng; Wang Jiwu

    2010-12-15

    Two novel inorganic-organic hybrid materials based on an organic dye cation methylene blue (MB) and Lindqvist-type POM polyanions, [C{sub 22}H{sub 18}N{sub 3}S]{sub 2}Mo{sub 6}O{sub 19} 2DMF (1) and [C{sub 22}H{sub 18}N{sub 3}S]{sub 2}W{sub 6}O{sub 19} 2DMF (2) were synthesized under ambient conditions and characterized by CV, IR spectroscopy, solid diffuse reflectance spectrum, UV-vis spectra in DMF solution, luminescent spectrum and single crystal X-ray diffraction. Crystallographic data reveal that compounds 1 and 2 are isostructural and both crystallize in the triclinic space group P1-bar . Their crystal structures present that the layers of organic molecules and inorganic anions array alternatively, and there exist strong {pi}...{pi} stacking interactions between dimeric MB cations and near distance interactions among organic dye cations, Lindqvist-type POM polyanions and DMF molecules. The solid diffuse reflectance spectra and UV-vis spectra in DMF solution appear new absorption bands ascribed to the charge-transfer transition between the cationic MB donor and the POM acceptors. Studies of the photoluminescent properties show that the formation of 1 and 2 lead to the fluorescence quenching of starting materials. -- Graphical abstract: Their crystal structures present that the layers of organic molecules and inorganic anions array alternatively, and there exist strong {pi}...{pi} stacking interactions between dimeric MB cations. Display Omitted

  17. Integrative Chemistry: Advanced functional cellular materials bearing multiscale porosity

    NASA Astrophysics Data System (ADS)

    Depardieu, M.; Kinadjian, N.; Backov, R.

    2015-07-01

    With this mini review we show through the sol-gel and emulsion-based Integrative Chemistry how it is possible to trigger materials dimensionality and beyond their functionalities when reaching enhanced applications. In here we focus on 3D macrocellular monolithic foams bearing hierarchical porosities and applications thereof. We first depict the general background of emulsions focusing on concentrated ones, acting as soft templates for the design of PolyHIPE foams, HIPE being the acronym of High Internal Phase Emulsions while encompassing both sol-gel and polymer chemistry. Secondly we extend this approach toward the design of hybrid organic-inorganic foams, labeled Organo-Si(HIPE), where photonics and heterogeneous catalysis applications are addressed. In a third section we show how inorganic Si(HIPE) matrices can be employed as sacrificial hard templates for the generation carbonaceous foams, labeled Carbon(HIPE). These foams being conductive we show applications when employed as electrodes for Li-S battery and as hosts for Li(BH4)-based hydrogen storage.

  18. Study of sample thickness dependence in electron-beam irradiation of self-developing inorganic materials

    NASA Astrophysics Data System (ADS)

    Chen, G. S.; Humphreys, C. J.

    1999-01-01

    In this study we apply a series of focused and overfocused electron probes with current densities ranging from 105 to 109A m-2 to irradiate electron-gun deposited thin films of amorphous AlF3 (a-AlF3)and amorphous SiO2(a-SiO2). Statistical distributions of the time deemed necessary to produce a given amount of mass loss from the two beam-irradiated materials are measured as functions of beam current density and sample thickness. According to those results, a-AlF3 is damaged in parallel throughout the irradiated volume of the sample as indicated by no detectable thickness dependence, whereas a-SiO2 displays a distinct scaling of characteristic drilling times with thickness indicative of a combination of surface and volume mass loss processes.

  19. Distribution of inorganic mercury in Sacramento River water and suspended colloidal sediment material

    USGS Publications Warehouse

    Roth, D.A.; Taylor, H.E.; Domagalski, J.; Dileanis, P.; Peart, D.B.; Antweiler, R.C.; Alpers, C.N.

    2001-01-01

    The concentration and distribution of inorganic Hg was measured using cold-vapor atomic fluorescence spectrometry in samples collected at selected sites on the Sacramento River from below Shasta Dam to Freeport, CA, at six separate times between 1996 and 1997. Dissolved (ultrafiltered, 0.005 ??m equivalent pore size) Hg concentrations remained relatively constant throughout the system, ranging from the detection limit (< 0.4 ng/L) to 2.4 ng/L. Total Hg (dissolved plus colloidal suspended sediment) concentrations ranged from the detection limit at the site below Shasta Dam in September 1996 to 81 ng/L at the Colusa site in January 1997, demonstrating that colloidal sediment plays an important role in the downriver Hg transport. Sequential extractions of colloid concentrates indicate that the greatest amount of Hg associated with sediment Was found in the "residual" (mineral) phase with a significant quantity also occurring in the "oxidizable" phase. Only a minor amount of Hg was observed in the "reducible" phase. Dissolved Hg loads remained constant or increased slightly in the downstream direction through the study area, whereas the total inorganic Hg load increased significantly downstream especially in the reach of the fiver between Bend Bridge and Colusa. Analysis of temporal variations showed that Hg loading was positively correlated to discharge.

  20. Assembly of one dimensional inorganic nanostructures into functional 2D and 3D architectures. Synthesis, arrangement and functionality.

    PubMed

    Joshi, Ravi K; Schneider, Jörg J

    2012-08-01

    This review will focus on the synthesis, arrangement, structural assembly, for current and future applications, of 1D nanomaterials (tubes, wires, rods) in 2D and 3D ordered arrangements. The ability to synthesize and arrange one dimensional nanomaterials into ordered 2D or 3D micro or macro sized structures is of utmost importance in developing new devices and applications of these materials. Micro and macro sized architectures based on such 1D nanomaterials (e.g. tubes, wires, rods) provide a platform to integrate nanostructures at a larger and thus manageable scale into high performance electronic devices like field effect transistors, as chemo- and biosensors, catalysts, or in energy material applications. Carbon based, metal oxide and metal based 1D arranged materials as well as hybrid or composite 1D materials of the latter provide a broad materials platform, offering a perspective for new entries into fascinating structures and future applications of such assembled architectures. These architectures allow bridging the gap between 1D nanostructures and the micro and macro world and are the basis for an assembly of 1D materials into higher hierarchy domains. This critical review is intended to provide an interesting starting point to view the current state of the art and show perspectives for future developments in this field. The emphasis is on selected nanomaterials and the possibilities for building three dimensional arrays starting from one dimensional building blocks. Carbon nanotubes, metal oxide nanotubes and nanowires (e.g. ZnO, TiO(2), V(2)O(5), Cu(2)O, NiO, Fe(2)O(3)), silicon and germanium nanowires, and group III-V or II-VI based 1D semiconductor nanostructures like GaS and GaN, pure metals as well as 1D hybrid materials and their higher organized architectures (foremost in 3D) will be focussed. These materials have been the most intensively studied within the last 5-10 years with respect to nano-micro integration aspects and their functional and application oriented properties. The critical review should be interesting for a broader scientific community (chemists, physicists, material scientists) interested in synthetic and functional material aspects of 1D materials as well as their integration into next higher organized architectures. PMID:22722888

  1. Inorganic contents of peats

    SciTech Connect

    Raymond, R. Jr.; Bish, D.L.; Cohen, A.D.

    1988-02-01

    Peat, the precursor of coal, is composed primarily of plant components and secondarily of inorganic matter derived from a variety of sources. The elemental, mineralogic, and petrographic composition of a peat is controlled by a combination of both its botanical and depositional environment. Inorganic contents of peats can vary greatly between geographically separated peat bogs as well as vertially and horizontally within an individual bog. Predicting the form and distribution of inorganic matter in a coal deposit requires understanding the distribution and preservation of inorganic matter in peat-forming environments and diagenetic alterations affecting such material during late-stage peatification and coalification processes. 43 refs., 4 figs., 3 tabs.

  2. Photopolymerization of hybrid organic/inorganic materials based on nanostructured units for photonic applications

    NASA Astrophysics Data System (ADS)

    Fortunati, I.; Dainese, T.; Signorini, R.; Bozio, R.; Tagliazucca, V.; Dirè, S.; Lemercier, G.; Mulatier, J.-C.; Andraud, C.; Schiavuta, P.; Bottazzo, Y.; Della Giustina, G.; Brusatin, G.; Guglielmi, M.

    2007-09-01

    In this work we report on the study of the photopolymerization process in hybrid organic-inorganic films containing photopolymerizable acrylic and methacrylic groups and. The films are doped with a proper photo-initiator for radical polymerization of (meth)acrylic units and are prepared using the sol-gel technique. The photo-initiator is activated by using continuum (single-photon polymerization) or pulsed (two-photon polymerization) laser sources at different wavelengths. After the development of the unexposed regions with a suitable solvent, the photopolymerized structures are observed with microscopy techniques. The effects of the composition of the photopolymerizable mixture, the irradiation parameters (laser power and exposure time) and the external atmosphere in which the photopolymerization is performed are investigated. The fabrication of 3D microstructures using multiphoton absorption processes is a promising technique that involves low amount of incident exposure dose with potentially high spatial resolution.

  3. Towards rational design of peptides for selective interaction with inorganic materials

    E-print Network

    Krauland, Eric Mark

    2007-01-01

    Utilizing molecular recognition and self-assembly, material-specific biomolecules have shown great promise for engineering and ordering materials at the nanoscale. These molecules, inspired from natural biomineralization ...

  4. New organic-inorganic hybrid molecular systems and highly organized materials in catalysis

    NASA Astrophysics Data System (ADS)

    Kustov, L. M.

    2015-11-01

    Definitions of hybrid materials are suggested, and applications of these materials are considered. Particular attention is focused on the application of hybrid materials in hydrogenation, partial oxidation, plant biomass conversion, and natural gas reforming, primarily on the use of core-shell nanoparticles and decorated metal nanoparticles in these reactions. Application prospects of various hybrid materials, particularly those of metal-organic frameworks, are discussed.

  5. Functionally graded materials: Design, processing and applications

    SciTech Connect

    Miyamoto, Y.; Kaysser, W.A.; Rabin, B.H.; Kawasaki, A.; Ford, R.G.

    1999-09-01

    In a Functionally Graded Material (FGM), the composition and structure gradually change over volume, resulting in corresponding changes in the properties of the material. By applying the many possibilities inherent in the FGM concept, it is anticipated that materials will be improved and new functions for them created. A comprehensive description of design, modeling, processing, and evaluation of FGMs as well as their applications is covered in this book. The contents include: lessons from nature; graded microstructures; modeling and design; characterization of properties; processing and fabrication; applications; and summary and outlook.

  6. An Effective Way to Optimize the Functionality of Graphene-Based Nanocomposite: Use of the Colloidal Mixture of Graphene and Inorganic Nanosheets

    NASA Astrophysics Data System (ADS)

    Jin, Xiaoyan; Adpakpang, Kanyaporn; Young Kim, In; Mi Oh, Seung; Lee, Nam-Suk; Hwang, Seong-Ju

    2015-06-01

    The best electrode performance of metal oxide-graphene nanocomposite material for lithium secondary batteries can be achieved by using the colloidal mixture of layered CoO2 and graphene nanosheets as a precursor. The intervention of layered CoO2 nanosheets in-between graphene nanosheets is fairly effective in optimizing the pore and composite structures of the Co3O4-graphene nanocomposite and also in enhancing its electrochemical activity via the depression of interaction between graphene nanosheets. The resulting CoO2 nanosheet-incorporated nanocomposites show much greater discharge capacity of ~1750 mAhg-1 with better cyclability and rate characteristics than does CoO2-free Co3O4-graphene nanocomposite (~1100?mAhg-1). The huge discharge capacity of the present nanocomposite is the largest one among the reported data of cobalt oxide-graphene nanocomposite. Such a remarkable enhancement of electrode performance upon the addition of inorganic nanosheet is also observed for Mn3O4-graphene nanocomposite. The improvement of electrode performance upon the incorporation of inorganic nanosheet is attributable to an improved Li+ ion diffusion, an enhanced mixing between metal oxide and graphene, and the prevention of electrode agglomeration. The present experimental findings underscore an efficient and universal role of the colloidal mixture of graphene and redoxable metal oxide nanosheets as a precursor for improving the electrode functionality of graphene-based nanocomposites.

  7. Continuous spray forming of functionally gradient materials

    SciTech Connect

    McKechnie, T.N.; Richardson, E.H.

    1995-12-01

    Researchers at Plasma Processes Inc. have produced a Functional Gradient Material (FGM) through advanced vacuum plasma spray processing for high heat flux applications. Outlined in this paper are the manufacturing methods used to develop a four component functional gradient material of copper, tungsten, boron, and boron nitride. The FGM was formed with continuous gradients and integral cooling channels eliminating bondlines and providing direct heat transfer from the high temperature exposed surface to a cooling medium. Metallurgical and x-ray diffraction analyses of the materials formed through innovative VPS (vacuum plasma spray) processing are also presented. Applications for this functional gradient structural material range from fusion reactor plasma facing components to missile nose cones to boilers.

  8. Colloidal CuInS2 Quantum Dots as Inorganic Hole-Transporting Material in Perovskite Solar Cells.

    PubMed

    Lv, Mei; Zhu, Jun; Huang, Yang; Li, Yi; Shao, Zhipeng; Xu, Yafeng; Dai, Songyuan

    2015-08-12

    To develop novel hole-transporting materials (HTMs) is an important issue of perovskite solar cells (PSCs), especially favoring the stability improvement and the cost reduction. Herein, we use ternary quantum dots (QDs) as HTM in mesoporous TiO2/CH3NH3PbI3/HTM/Au solar cell, and modify the surface of CuInS2 QDs by cation exchange to improve the carrier transport. The device efficiency using CuInS2 QDs with a ZnS shell layer as HTM is 8.38% under AM 1.5, 100 mW cm(-2). The electrochemical impedance spectroscopy suggested that the significantly enhanced performance is mainly attributed to the reduced charge recombination between TiO2 and HTM. It paves a new pathway for the future development of cheap inorganic HTMs for the high efficiency PSCs. PMID:26186007

  9. Oxide nanomaterials Selbach, Inorganic

    E-print Network

    Oxide nanomaterials Selbach, Inorganic Materials and Ceramics Research Group · Ferroelectrics & mulAferroics · Thermoelectrics · Transparent conducAng oxide · Quantum dotsAvity within ceramic engineering, solid state chemistry, nanoparAcles, thin films

  10. TRANSPORT OF INORGANIC COLLOIDS THROUGH NATURAL AQUIFER MATERIAL: IMPLICATIONS FOR CONTAMINANT TRANSPORT

    EPA Science Inventory

    The stability and transport of radiolabeled Fe2O3 particles were studied using laboratory batch and column techniques. Core material collected from a shallow sand and gravel aquifer was used as the immobile column matrix material. Variables in the study incl...

  11. TRANSPORT OF INORGANIC COLLOIDS THROUGH NATURAL AQUIFER MATERIAL: IMPLICATIONS FOR CONTAMINANT TRANSPORT

    EPA Science Inventory

    The stability and transport of radiolabeled Fe2O3 particles were studied using laboratory batch and column techniques. ore material collected from a shallow sand and gravel aquifer was used as the immobile column matrix material. ariables in the study included flow rate, pH, ioni...

  12. LABORATORY STUDIES ON THE STABILITY AND TRANSPORT OF INORGANIC COLLOIDS THROUGH NATURAL AQUIFER MATERIAL

    EPA Science Inventory

    The stability and transport of radio-labeled Fe2O3 particles were studied using laboratory batch and column techniques. Core material collected from shallow sand and gravel aquifer was used as the immobile column matrix material. Variables in the study included flow rate, pH, i...

  13. Terahertz and infrared transmission of an organic/inorganic hybrid thermoelectric material

    SciTech Connect

    Heyman, J. N. Alebachew, B. A.; Kaminski, Z. S.; Nguyen, M. D.; Coates, N. E.; Urban, J. J.

    2014-04-07

    We report terahertz and infrared transmission measurements of a high-performance thermoelectric material containing tellurium nanowires in a conducting polymer poly(3,4-ethylenedioxythiophene):poly(styrenesulfonate) (PEDOT:PSS) matrix. The DC electrical conductivity of the hybrid material (41?S/cm) is approximately one hundred times that of pure PEDOT:PSS and more than 400 times that of a film of pure tellurium nanowires, while the terahertz-frequency (THz) conductivity of PEDOT:PSS and the hybrid material are comparable at f???2THz. A frequency-dependent conductivity model indicates that the increased DC conductivity of the hybrid material results from an increase in the DC charge mobility rather than in the free charge density. We suggest that the increased DC conductivity of the hybrid material results from an increase in linkage between PEDOT domains by the tellurium nanowires.

  14. Improved electronic coupling in hybrid organic-inorganic nanocomposites employing thiol-functionalized P3HT and bismuth sulfide nanocrystals

    NASA Astrophysics Data System (ADS)

    Martinez, L.; Higuchi, S.; MacLachlan, A. J.; Stavrinadis, A.; Miller, N. C.; Diedenhofen, S. L.; Bernechea, M.; Sweetnam, S.; Nelson, J.; Haque, S. A.; Tajima, K.; Konstantatos, G.

    2014-08-01

    In this study, we employ a thiol-functionalized polymer (P3HT-SH) as a leverage to tailor the nanomorphology and electronic coupling in polymer-nanocrystal composites for hybrid solar cells. The presence of the thiol functional group allows for a highly crystalline semiconducting polymer film at low thiol content and allows for improved nanomorphologies in hybrid organic-inorganic systems when employing non-toxic bismuth sulfide nanocrystals. The exciton dissociation efficiency and carrier dynamics at this hybrid heterojunction are investigated through photoluminescence quenching and transient absorption spectroscopy measurements, revealing a larger degree of polaron formation when P3HT-SH is employed, suggesting an increased electronic interaction between the metal chalcogenide nanocrystals and the thiol-functionalized P3HT. The fabricated photovoltaic devices show 15% higher power conversion efficiencies as a result of the improved nanomorphology and better charge transfer mechanism together with the higher open circuit voltages arising from the deeper energy levels of P3HT-SH.In this study, we employ a thiol-functionalized polymer (P3HT-SH) as a leverage to tailor the nanomorphology and electronic coupling in polymer-nanocrystal composites for hybrid solar cells. The presence of the thiol functional group allows for a highly crystalline semiconducting polymer film at low thiol content and allows for improved nanomorphologies in hybrid organic-inorganic systems when employing non-toxic bismuth sulfide nanocrystals. The exciton dissociation efficiency and carrier dynamics at this hybrid heterojunction are investigated through photoluminescence quenching and transient absorption spectroscopy measurements, revealing a larger degree of polaron formation when P3HT-SH is employed, suggesting an increased electronic interaction between the metal chalcogenide nanocrystals and the thiol-functionalized P3HT. The fabricated photovoltaic devices show 15% higher power conversion efficiencies as a result of the improved nanomorphology and better charge transfer mechanism together with the higher open circuit voltages arising from the deeper energy levels of P3HT-SH. Electronic supplementary information (ESI) available: 1H NMR images of P3HT-SH, transient absorption spectra measurements of P3HT and P3HT-SH, photoelectron spectroscopy and hole mobility studies of P3HT and P3HT-SH and optimization of the hybrid organic-inorganic solar cells. See DOI: 10.1039/c4nr01679c

  15. Fracture Analysis of Functionally Graded Materials

    SciTech Connect

    Zhang, Ch.; Gao, X. W.; Sladek, J.; Sladek, V.

    2010-05-21

    This paper reports our recent research works on crack analysis in continuously non-homogeneous and linear elastic functionally graded materials. A meshless boundary element method is developed for this purpose. Numerical examples are presented and discussed to demonstrate the efficiency and the accuracy of the present numerical method, and to show the effects of the material gradation on the crack-opening-displacements and the stress intensity factors.

  16. Development of Pillared M(IV) Phosphate Phosphonate Inorganic Organic Hybrid Ion Exchange Materials for Applications in Separations found in the Nuclear Fuel Cycle 

    E-print Network

    Burns, Jonathan

    2012-10-02

    is to implement a liquid-solid separation process to reduce waste and risk of contamination by the development of metal(IV) phosphate phosphonate inorganic organic hybrid ion exchange materials with the ideal formula of M(O6P2C6H4)0.5(O3POA) * nH2O, where M = Zr...

  17. Meeting Materials for the 4th NRC Meeting on the Guidance for and the Review of EPA's Toxicological Assessment of Inorganic Arsenic

    EPA Science Inventory

    On December 2-3, 2015, the National Research Council (NRC) hosted the 4th meeting of the committee formed to peer review the draft IRIS assessment of inorganic arsenic. EPA presented background and overview materials during the public session on December 2nd. This information co...

  18. Flagellar filament bio-templated inorganic oxide materials – towards an efficient lithium battery anode

    PubMed Central

    Beznosov, Sergei N.; Veluri, Pavan S.; Pyatibratov, Mikhail G.; Chatterjee, Abhijit; MacFarlane, Douglas R.; Fedorov, Oleg V.; Mitra, Sagar

    2015-01-01

    Designing a new generation of energy-intensive and sustainable electrode materials for batteries to power a variety of applications is an imperative task. The use of biomaterials as a nanosized structural template for these materials has the potential to produce hitherto unachievable structures. In this report, we have used genetically modified flagellar filaments of the extremely halophilic archaea species Halobacterium salinarum to synthesize nanostructured iron oxide composites for use as a lithium-ion battery anode. The electrode demonstrated a superior electrochemical performance compared to existing literature results, with good capacity retention of 1032?mAh g?1 after 50 cycles and with high rate capability, delivering 770?mAh g?1 at 5?A g?1 (~5 C) discharge rate. This unique flagellar filament based template has the potential to provide access to other highly structured advanced energy materials in the future. PMID:25583370

  19. Flagellar filament bio-templated inorganic oxide materials - towards an efficient lithium battery anode

    NASA Astrophysics Data System (ADS)

    Beznosov, Sergei N.; Veluri, Pavan S.; Pyatibratov, Mikhail G.; Chatterjee, Abhijit; Macfarlane, Douglas R.; Fedorov, Oleg V.; Mitra, Sagar

    2015-01-01

    Designing a new generation of energy-intensive and sustainable electrode materials for batteries to power a variety of applications is an imperative task. The use of biomaterials as a nanosized structural template for these materials has the potential to produce hitherto unachievable structures. In this report, we have used genetically modified flagellar filaments of the extremely halophilic archaea species Halobacterium salinarum to synthesize nanostructured iron oxide composites for use as a lithium-ion battery anode. The electrode demonstrated a superior electrochemical performance compared to existing literature results, with good capacity retention of 1032 mAh g-1 after 50 cycles and with high rate capability, delivering 770 mAh g-1 at 5 A g-1 (~5 C) discharge rate. This unique flagellar filament based template has the potential to provide access to other highly structured advanced energy materials in the future.

  20. Functional polarity of the tentacle of the sea anemone Anemonia viridis: role in inorganic carbon acquisition.

    PubMed

    Furla, P; Bénazet-Tambutté, S; Jaubert, J; Allemand, D

    1998-02-01

    The oral epithelial layers of anthozoans have a polarized morphology: photosynthetic endosymbionts live within endodermal cells facing the coelenteric cavity and are separated from the external seawater by the ectodermal layer and the mesoglea. To study if this morphology plays a role in the supply of inorganic carbon for symbiont photosynthesis, we measured the change in pH and the rate of OH- (H+) fluxes induced by each cell layer on a tentacle of the sea anemone Anemonia viridis. Light-induced pH increase of the medium bathing the endodermal layers led to the generation of a transepithelial pH gradient of approximately 0.8 pH units across the tentacle, whereas darkness induced acidification of this medium. The light-induced pH change was associated with an increase of total alkalinity. Only the endodermal layer was able to induce a net OH- secretion (H+ absorption). The light-induced OH- secretion by the endodermal cell layer was dependent on the presence of HCO3- in the compartment facing the ectoderm and was sensitive to several inhibitors of ion transport. [14C] HCO3- incorporation into photosynthates confirmed the ectodermal supply, the extent of which varied from 25 to > 90%, according to HCO3- availability. Our results suggest that the light-induced OH- secretion by the endodermal cell layer followed the polarized transport of HCO3- and its subsequent decarboxylation within the endodermal cell layer. This polarity may play a significant role both in inorganic carbon absorption and in the control of light-enhanced calcification in scleractinian corals. PMID:9486285

  1. Geochemical and mineralogical interpretation of the Viking inorganic chemical results. [for Martian surface materials

    NASA Technical Reports Server (NTRS)

    Toulmin, P., III; Rose, H. J., Jr.; Christian, R. P.; Baird, A. K.; Evans, P. H.; Clark, B. C.; Keil, K.; Kelliher, W. C.

    1977-01-01

    The current status of geochemical, mineralogical, petrological interpretation of refined Viking Lander data is reviewed, and inferences that can be drawn from data on the composition of Martian surface materials are presented. The materials are dominantly fine silicate particles admixed with, or including, iron oxide particles. Both major element and trace element abundances in all samples are indicative of mafic source rocks (rather than more highly differentiated salic materials). The surface fines are nearly identical in composition at the two widely separated Lander sites, except for some lithologic diversity at the 100-m scale. This implies that some agency (presumably aeolian processes) has thoroughly homogenized them on a planetary scale. The most plausible model for the mineralogical constitution of the fine-grained surface materials at the two Lander sites is a fine-grained mixture dominated by iron-rich smectites, or their degradation products, with ferric oxides, probably including maghemite and carbonates (such as calcite), but not such less stable phases as magnesite or siderite.

  2. Certified reference materials for inorganic and organic contaminants in environmental matrices.

    PubMed

    Ulberth, Franz

    2006-10-01

    Chemical measurements often constitute the basis for informed decision-making at different levels in society; sound decision-making is possible only if the quality of the data used is uncompromised. To guarantee the reliability and comparability of analytical data an intricate system of quality-assurance measures has to be put into effect in a laboratory. Reference materials and, in particular, certified reference materials (CRMs) are essential for achieving traceability and comparability of measurement results between laboratories and over time. As in any other domain of analytical chemistry, techniques used to monitor the levels and fate of contaminants in the environment must be calibrated using appropriate calibration materials, and the methods must be properly validated using fit-for-purpose matrix-matched CRMs, to ensure confidence in the data produced. A sufficiently large number of matrix CRMs are available for analysis of most elements, and the group of chemicals known as persistent organic pollutants, in environmental compartments and biota. The wide variety of analyte/level/matrix/matrix property combinations available from several suppliers enables analysts to select CRMs which sufficiently match the properties of the samples they analyse routinely. Materials value-assigned for the so-called emerging pollutants are scarce at the moment, though an objective of current development programmes of CRM suppliers is to overcome this problem. PMID:16953324

  3. Final Report: Photo-Directed Molecular Assembly of Multifunctional Inorganic Materials

    SciTech Connect

    B.G. Potter, Jr.

    2010-10-15

    This final report details results, conclusions, and opportunities for future effort derived from the study. The work involved combining the molecular engineering of photoactive Ti-alkoxide systems and the optical excitation of hydrolysis and condensation reactions to influence the development of the metal-oxygen-metal network at the onset of material formation. Selective excitation of the heteroleptic alkoxides, coupled with control of alkoxide local chemical environment, enabled network connectivity to be influenced and formed the basis for direct deposition and patterning of Ti-oxide-based materials. The research provided new insights into the intrinsic photoresponse and assembly of these complex, alkoxide molecules. Using a suite of electronic, vibrational, and nuclear spectroscopic probes, coupled with quantum chemical computation, the excitation wavelength and fluence dependence of molecular photoresponse and the nature of subsequent hydrolysis and condensation processes were probed in pyridine-carbinol-based Ti-alkoxides with varied counter ligand groups. Several methods for the patterning of oxide material formation were demonstrated, including the integration of this photoprocessing approach with conventional, dip-coating methodologies.

  4. Modeling Bamboo as a Functionally Graded Material

    SciTech Connect

    Silva, Emilio Carlos Nelli; Walters, Matthew C.; Paulino, Glaucio H.

    2008-02-15

    Natural fibers are promising for engineering applications due to their low cost. They are abundantly available in tropical and subtropical regions of the world, and they can be employed as construction materials. Among natural fibers, bamboo has been widely used for housing construction around the world. Bamboo is an optimized composite material which exploits the concept of Functionally Graded Material (FGM). Biological structures, such as bamboo, are composite materials that have complicated shapes and material distribution inside their domain, and thus the use of numerical methods such as the finite element method and multiscale methods such as homogenization, can help to further understanding of the mechanical behavior of these materials. The objective of this work is to explore techniques such as the finite element method and homogenization to investigate the structural behavior of bamboo. The finite element formulation uses graded finite elements to capture the varying material distribution through the bamboo wall. To observe bamboo behavior under applied loads, simulations are conducted considering a spatially-varying Young's modulus, an averaged Young's modulus, and orthotropic constitutive properties obtained from homogenization theory. The homogenization procedure uses effective, axisymmetric properties estimated from the spatially-varying bamboo composite. Three-dimensional models of bamboo cells were built and simulated under tension, torsion, and bending load cases.

  5. Organic-inorganic lead halide perovskite solar cell materials: A possible stability problem

    NASA Astrophysics Data System (ADS)

    Schoonman, J.

    2015-01-01

    The methyl ammonium lead halides are promising visible-light absorbers for application in solar cells. The most common synthetic routes use the solid binary halides as one of the starting compounds. These binary lead halides exhibit photodecomposition. In view of the perovskite crystal structure of the methyl ammonium lead halides, it is possible that also here the lead halide parts may exhibit photodecomposition. The mechanism of the photodecomposition of the binary lead halides is presented in detail. Based on this mechanism the trapping of photo-generated electrons on the lead ions in these perovskite materials should be studied in detail.

  6. Crystallization of Oxides as Functional Materials

    NASA Astrophysics Data System (ADS)

    Sun, Congting; Song, Shuyan; Xue, Dongfeng; Zhang, Hongjie

    2012-06-01

    Crystallization is essential to the manufacture of functional materials as varies as electronic devices, energy storage and conversion devices, and highly reactive catalysts. As an important part of functional materials, metal oxides possess wide applications and the crystallization of oxide materials has thus received considerable attention from both fundamental and technological perspectives. With particular emphasis on our recent laboratory results, this feature article gives a brief review in the field of crystallization of oxides. On the basis of chemical bonding theory of single crystal growth, we have simulated thermodynamic growth behaviors of various functional oxides such as ZnO, MgO, Cu2O, Nb2O5, V2O5, MnO2, SnO2, NiO, KDP/ADP, LiNbO3, and NaNbO3. Quantitatively analyzing bonding conditions of controllable crystallographic faces enables us to design proper synthesis strategies and optimize growth parameters, consequently obtaining functional oxides with desirable crystallization behaviors.

  7. Inorganic-organic solar cells based on quaternary sulfide as absorber materials.

    PubMed

    Hong, Tiantian; Liu, Zhifeng; Yan, Weiguo; Liu, Junqi; Zhang, Xueqi

    2015-11-18

    We report a novel promising quaternary sulfide (CuAgInS) to serve as a semiconductor sensitizer material in the photoelectrochemical field. In this study, CuAgInS (CAIS) sulfide sensitized ZnO nanorods were fabricated on ITO substrates through a facile and low-cost hydrothermal chemical method and applied on photoanodes for solar cells for the first time. The component and stoichiometry were key factors in determining the photoelectric performance of CAIS sulfide, which were controlled by modulating their reaction time. ZnO/Cu0.7Ag0.3InS2 nanoarrays exhibit an enhanced optical and photoelectric performance and the power conversion efficiency of ITO/ZnO/Cu0.7Ag0.3InS2/P3HT/Pt solid-state solar cell was up to 1.80%. The remarkable performance stems from improved electron transfer, a higher efficiency of light-harvesting and appropriate band gap alignment at the interface of the ZnO/Cu0.7Ag0.3InS2 NTs. The research indicates that CAIS as an absorbing material has enormous potential in solar cell systems. PMID:26553746

  8. A "single-sample concept" (SSC): a new approach to the combinatorial chemistry of inorganic materials.

    PubMed

    Hulliger, Jürg; Awan, Muhammad Aslam

    2004-10-01

    Combinatorial estimations show that, within an unreacted ceramic sample prepared by mixing N different starting materials MxOy with average particle size approximately 1 microm, there are about 10(12) grains per cubic centimeter, sufficient for local reactions to occur that may produce a larger number of product oxides than presently accessible by 2D plate techniques. The "single-sample concept" (SSC) is proposed for performing property-directed syntheses for the preparation of ferri-/ferromagnetic or superconducting compounds. Because of the magnetic properties of the products, libraries of product grains can be sorted by means of magnetic separation techniques. For materials with a large magnetization, the separation efficiency is so high that traces of products can be isolated. The SSC concept was tested experimentally to prepare Fe-based oxides (N=17, 24, 30). The large yields (<75 wt %, N=17) of product grains agree with the literature data, which indicate that 3d metal magnetic oxide phases (Tc>300 K) are most probably Fe oxides. In combination with magnetic separation techniques, SSC seems particularly adapted for exploring the solid-state chemistry of metallic lead elements that form ferri-/ferromagnetic or superconducting oxide phases difficult to detect systematically within the large phase space of theoretically existing compounds. PMID:15372658

  9. Thermal evaporation furnace with improved configuration for growing nanostructured inorganic materials

    NASA Astrophysics Data System (ADS)

    Joanni, E.; Savu, R.; Valadares, L.; Cilense, M.; Zaghete, M. A.

    2011-06-01

    A tubular furnace specifically designed for growing nanostructured materials is presented in this work. The configuration allows an accurate control of evaporation temperature, substrate temperature, total pressure, oxygen partial pressure, volumetric flow and source-substrate distance, with the possibility of performing both downstream and upstream depositions. In order to illustrate the versatility of the equipment, the furnace was used for growing semiconducting oxide nanostructures under different deposition conditions. Highly crystalline indium oxide nanowires with different morphologies were synthesized by evaporating mixtures of indium oxide and graphite powders with different mass ratios at temperatures between 900 °C and 1050 °C. The nanostructured layers were deposited onto oxidized silicon substrates with patterned gold catalyst in the temperature range from 600 °C to 900 °C. Gas sensors based on these nanowires exhibited enhanced sensitivity towards oxygen, with good response and recovery times.

  10. Thermal evaporation furnace with improved configuration for growing nanostructured inorganic materials.

    PubMed

    Joanni, E; Savu, R; Valadares, L; Cilense, M; Zaghete, M A

    2011-06-01

    A tubular furnace specifically designed for growing nanostructured materials is presented in this work. The configuration allows an accurate control of evaporation temperature, substrate temperature, total pressure, oxygen partial pressure, volumetric flow and source-substrate distance, with the possibility of performing both downstream and upstream depositions. In order to illustrate the versatility of the equipment, the furnace was used for growing semiconducting oxide nanostructures under different deposition conditions. Highly crystalline indium oxide nanowires with different morphologies were synthesized by evaporating mixtures of indium oxide and graphite powders with different mass ratios at temperatures between 900 °C and 1050 °C. The nanostructured layers were deposited onto oxidized silicon substrates with patterned gold catalyst in the temperature range from 600 °C to 900 °C. Gas sensors based on these nanowires exhibited enhanced sensitivity towards oxygen, with good response and recovery times. PMID:21721724

  11. Layered tungsten oxide-based organic/inorganic hybrid materials I: Infrared and Raman study

    E-print Network

    B. Ingham; S. V. Chong; J. L. Tallon

    2004-05-12

    Tungsten oxide-organic layered hybrid materials have been studied by infrared and Raman spectroscopy, and demonstrate a difference in bonding nature as the length of the interlayer organic `spacer' molecule is increased. Ethylenediamine-tungsten oxide clearly displays a lack of terminal -NH3+ ammonium groups which appear in hybrids with longer alkane molecules, thus indicating that the longer chains are bound by electrostatic interactions as well as or in place of the hydrogen bonding that must be present in the shorter chain ethylenediamine hybrids. The presence of organic molecules between the tungsten oxide layers, compared with the layered tungstic acid H2WO4, shows a decrease in the apical W=O bond strength, as might be expected from the aforementioned electrostatic interaction.

  12. Organic-inorganic hybrid materials towards passive and active architectures for the next generation of optical networks

    NASA Astrophysics Data System (ADS)

    Ferreira, R. A. S.; André, P. S.; Carlos, L. D.

    2010-09-01

    The advances in optoelectronics over the last three decades have been quite dramatic, namely the mass manufacturing of low cost integrated circuits, revolutionizing the speed and the capability of computing and communication. However, today's ever-increasing demand for high-bandwidth data is outgrowing the performance of electronics in many applications, such as in telecommunications where the traffic demand has been increasing steadily and, therefore, the transmission technology requires bandwidth that exceeds the one provided by actual copper based networks. In this context, the fabrication of low-cost integrated optics (IO) devices using sol-gel derived organic-inorganic hybrid (OIH) materials has received increasing attention in the last years. This review will focus on examples of OIHs that can be used in IO devices for the next generation of optical networks. Emphasis will be given to passive (planar and channel waveguides, couplers and multimode interference splitters) and active (lasers and optical amplifiers) optical architectures for long haul/metro and access/indoor networks.

  13. Design of a multifunctional nanohybrid system of the phytohormone gibberellic acid using an inorganic layered double-hydroxide material.

    PubMed

    Hafez, Inas H; Berber, Mohamed R; Minagawa, Keiji; Mori, Takeshi; Tanaka, Masami

    2010-09-22

    To offer a multifunctional and applicable system of the high-value biotechnological phytohormone gibberellic acid (GA), a nanohybrid system of GA using the inorganic Mg-Al layered double-hydroxide material (LDH) was formulated. The ion-exchange technique of LDH was applied to synthesize the GA-LDH hybrid. The hybrid structure of GA-LDH was confirmed by different spectroscopic techniques. The nanohybrid size was described by SEM to be ?0.1 ?m. The GA-LDH nanohybrid structure was the key parameter that controlled GA properties. The layered molecular structure of LDH limited the interaction of GA molecules in two-dimensional directions. Accordingly, GA molecules did not crystallize and were released in an amorphous form suitable for dissolution. At various simulated soil solutions, the nanohybrids showed a sustained release process following Higuchi kinetics. The biodegradation process of the intercalated GA showed an extended period of soil preservation as well as a slow rate of degradation. PMID:20722412

  14. Materials Suitable for preparing Inorganic Nanocasts of butterflies and other insects

    NASA Astrophysics Data System (ADS)

    Silver, J.; Fern, G. R.; Ireland, T. G.

    2015-06-01

    Replication of 3D-structures, in particular those that have a periodic modulation of a dielectric material at optical wavelengths and below have proven very difficult to fabricate. The majority of such replication techniques are complex or use moisture sensitive precursors requiring the use of for example a glove box. Here we demonstrate how an air stable supersaturated europium-doped yttrium nitrate phosphor precursor solution has the ability to easily impregnate a structure or produce a cast yielding faithful replicas composed of Y2O:Eu3+ after a final short annealing step. New replicas of Lepidoptera (moth) wing scales using field emission scanning electron microscopy, structures down to 10 nm have been imaged. Moreover as these replicas are made of phosphors, their luminescence in some cases may be modulated by the internal periodic modulation built into their structures. In this work we will discuss more recent results on the use of the phosphors for making nanocasts of moth wing scales and show a range of beautiful pictures to show what the method can achieve.

  15. Study of high resistance inorganic coatings on graphite fibers. [for graphite-epoxy composite materials

    NASA Technical Reports Server (NTRS)

    Galasso, F. S.; Veltri, R. D.; Scola, D. A.

    1979-01-01

    Coatings made of boron, silicon carbide, silica, and silica-like materials were studied to determine their ability to increase resistance of graphite fibers. The most promising results were attained by chemical vapor depositing silicon carbide on graphite fiber followed by oxidation, and drawing graphite fiber through ethyl silicate followed by appropriate heat treatments. In the silicon carbide coating studies, no degradation of the graphite fibers was observed and resistance values as high as three orders of magnitude higher than that of the uncoated fiber was attained. The strength of a composite fabricated from the coated fiber had a strength which compared favorably with those of composites prepared from uncoated fiber. For the silica-like coated fiber prepared by drawing the graphite fiber through an ethyl silicate solution followed by heating, coated fiber resistances about an order of magnitude greater than that of the uncoated fiber were attained. Composites prepared using these fibers had flexural strengths comparable with those prepared using uncoated fibers, but the shear strengths were lower.

  16. Chemo-mechanical microscale characterization of materials heterogeneity in oil/gas shales: linking organics and inorganics

    NASA Astrophysics Data System (ADS)

    Ferralis, N.; Abedi, S.; Grossman, J. C.; Ulm, F.

    2013-12-01

    From a materials perspective, the unconventional peculiarity of oil/gas shales resides in the intrinsic multi-scale heterogeneity in their chemical composition, organic maturity, mineralogy and microtexture. In contrast to common assumptions of maturity being driven only by the reservoir conditions (temperature and pressure), the presence of organic matter with different maturity within a few microns apart calls into question the role played by the organic and mineral heterogeneity into the chemo-mechanical properties of the material. Understanding how the upscaling of chemical diversity affects the fracturability and in general the mechanical strength of oil/gas shales is crucial. Compared to conventional oil and gas reservoirs, as well as coal, such heterogeneity requires novel and additional characterization tools from nano- to macro-scales to allow for a complete understanding of the role played by such heterogeneity in the chemo- mechanical properties of gas shales. Here we present a novel suite of chemical and mineralogical characterization tools that allow the in situ, non-destructive imaging of organic maturity and mineralogy from the microscale to the millimeter scale. This method is based on a combination of Raman, fluorescence and UV-Visible absorption spectroscopy. The upscaling is designed to provide a maturity population distribution from the nanoscale to the conventionally used macro-scale averaged parameters (such as vitrinite reflectance). Furthermore, in combination with registered micro/nano-mechanical indentation data a direct correlation of fracture mechanics and chemistry is made, allowing for the determination of high yield strain regions, relations between organic and inorganic anisotropy and interface mechanics. The underlying scientific insight at the nano and micro-scale of the potential origin of fractures in oil/gas shales, will potentially provide a connection bottom-up link to continuum fracture mechanics.

  17. Assembly of three organic-inorganic hybrid supramolecular materials based on reduced molybdenum(V) phosphates

    NASA Astrophysics Data System (ADS)

    Zhang, He; Yu, Kai; Lv, Jing-Hua; Wang, Chun-Mei; Wang, Chun-Xiao; Zhou, Bai-Bin

    2014-09-01

    Three supramolecular materials based on {P4Mo6} polyoxoanions, (Hbbi)2(H2bbi)[Cu3Mo12VO24(OH)6(H2O)6(HPO4)4(H2PO4)2(PO4)2]·3H2O (1), (Hbbi)2(H2bbi)[Ni3Mo12VO24(OH)6(H2O)2(HPO4)4(H2PO4)2(PO4)2]·9H2O (2), (Hbpy)(bpy)3[Ni2(H2O)10Na(PCA)2][NiMo12VO24(OH)6(H2PO4)6(PO4)2]·6H2O (3) (bbi=1,1?-(1,4-butanediyl)bis(imidazole), bpy=4,4?-bipyridine, PCA=pyridine-4-carboxylic acid), have been hydrothermally synthesized and structurally characterized by the elemental analysis, TG, IR, UV-vis, PXRD and the single-crystal X-ray diffraction. Compounds 1 and 2 exhibit covalent 1-D chains constructed from M[P4Mo6]2 dimeric cluster and {M(H2O)n} (M=Cu, n=3 for 1 and M=Ni, n=1 for 2) linker. Compound 3 possesses an unusual POMMOF supramolecular layers based on [Ni(P4Mo6)]2 dimeric units and 1-D metal-organic strings [Ni(H2O)5Na(PCA)]n, in which an in situ ligand of PCA from 1,3-bis(4-pyridyl)propane (bpp) precursor was observed. Furthermore, the electrochemical behavior of 1-3-CPE and magnetic properties of 1-3 have been investigated in detail.

  18. Inorganic separator technology program

    NASA Technical Reports Server (NTRS)

    Smatko, J. S.; Weaver, R. D.; Kalhammer, F. R.

    1973-01-01

    Testing and failure analyses of silver zinc cells with largely inorganic separators were performed. The results showed that the wet stand and cycle life objective of the silver-zinc cell development program were essentially accomplished and led to recommendations for cell composition, design, and operation that should yield further improvement in wet and cycle life. A series of advanced inorganic materials was successfully developed and formulated into rigid and semiflexible separator samples. Suitable screening tests for evaluation of largely inorganic separators were selected and modified for application to the separator materials. The results showed that many of these formulations are potentially superior to previously used materials and permitted selection of three promising materials for further evaluation in silver-zinc cells.

  19. Low work function thermionic emission materials

    SciTech Connect

    Zavadil, K.R.; King, D.B.; Ruffner, J.A.

    1999-11-01

    Thermionic energy conversion in a microminiature format shows potential as a viable, high efficiency, on-chip power source. Microminiature thermionic converters (MTC) with inter-electrode spacings on the order of microns are currently being prototyped and evaluated at Sandia. The remaining enabling technology is the development of low work function materials and processes than can be integrated into these converters. In this report, the authors demonstrate a method of incorporating thin film emitters into converters using rf sputtering. They find that the resultant films possess a minimum work function of 1.2 eV. Practical energy conversion is hindered by surface work function non-uniformity. They postulate the source of this heterogeneity to be a result of limited bulk and surface transport of barium. Several methods are proposed for maximizing transport, including increased film porosity and the use of metal terminating layers. They demonstrate a novel method for incorporating film porosity based on metal interlayer coalescence.

  20. Flexible hydrogel-based functional composite materials

    DOEpatents

    2013-10-08

    A composite having a flexible hydrogel polymer formed by mixing an organic phase with an inorganic composition, the organic phase selected from the group consisting of a hydrogel monomer, a crosslinker, a radical initiator, and/or a solvent. A polymerization mixture is formed and polymerized into a desired shape and size.

  1. Improved electronic coupling in hybrid organic-inorganic nanocomposites employing thiol-functionalized P3HT and bismuth sulfide nanocrystals.

    PubMed

    Martinez, L; Higuchi, S; MacLachlan, A J; Stavrinadis, A; Miller, N C; Diedenhofen, S L; Bernechea, M; Sweetnam, S; Nelson, J; Haque, S A; Tajima, K; Konstantatos, G

    2014-09-01

    In this study, we employ a thiol-functionalized polymer (P3HT-SH) as a leverage to tailor the nanomorphology and electronic coupling in polymer-nanocrystal composites for hybrid solar cells. The presence of the thiol functional group allows for a highly crystalline semiconducting polymer film at low thiol content and allows for improved nanomorphologies in hybrid organic-inorganic systems when employing non-toxic bismuth sulfide nanocrystals. The exciton dissociation efficiency and carrier dynamics at this hybrid heterojunction are investigated through photoluminescence quenching and transient absorption spectroscopy measurements, revealing a larger degree of polaron formation when P3HT-SH is employed, suggesting an increased electronic interaction between the metal chalcogenide nanocrystals and the thiol-functionalized P3HT. The fabricated photovoltaic devices show 15% higher power conversion efficiencies as a result of the improved nanomorphology and better charge transfer mechanism together with the higher open circuit voltages arising from the deeper energy levels of P3HT-SH. PMID:25029606

  2. Magnetic spectroscopy and microscopy of functional materials

    SciTech Connect

    Jenkins, C.A.

    2011-01-28

    Heusler intermetallics Mn{sub 2}Y Ga and X{sub 2}MnGa (X; Y =Fe, Co, Ni) undergo tetragonal magnetostructural transitions that can result in half metallicity, magnetic shape memory, or the magnetocaloric effect. Understanding the magnetism and magnetic behavior in functional materials is often the most direct route to being able to optimize current materials for todays applications and to design novel ones for tomorrow. Synchrotron soft x-ray magnetic spectromicroscopy techniques are well suited to explore the the competing effects from the magnetization and the lattice parameters in these materials as they provide detailed element-, valence-, and site-specifc information on the coupling of crystallographic ordering and electronic structure as well as external parameters like temperature and pressure on the bonding and exchange. Fundamental work preparing the model systems of spintronic, multiferroic, and energy-related compositions is presented for context. The methodology of synchrotron spectroscopy is presented and applied to not only magnetic characterization but also of developing a systematic screening method for future examples of materials exhibiting any of the above effects. The chapter progression is as follows: an introduction to the concepts and materials under consideration (Chapter 1); an overview of sample preparation techniques and results, and the kinds of characterization methods employed (Chapter 2); spectro- and microscopic explorations of X{sub 2}MnGa/Ge (Chapter 3); spectroscopic investigations of the composition series Mn{sub 2}Y Ga to the logical Mn{sub 3}Ga endpoint (Chapter 4); and a summary and overview of upcoming work (Chapter 5). Appendices include the results of a Think Tank for the Graduate School of Excellence MAINZ (Appendix A) and details of an imaging project now in progress on magnetic reversal and domain wall observation in the classical Heusler material Co{sub 2}FeSi (Appendix B).

  3. Influence of hybrid inorganic/organic mesoporous and nanostructured materials on the cephalosporins' efficacy on different bacterial strains.

    PubMed

    Carmen Chifiriuc, M; Mihaiescu, D; Ilinca, E; Marutescu, L; Mihaescu, G; Mihai Grumezescu, A

    2012-12-01

    The aim of this study was to investigate the effect of different hybrid inorganic-organic micro- and nanomaterials (Fe(3)O(4)/PEG(600), Fe(3)O(4)/C(12), ZSM-5) on the antibacterial activity of different cephalosporins against Gram-positive and Gram-negative bacterial strains. The synergic effect of the studied materials was demonstrated by the increase in the growth inhibition zones diameter. All tested hybrid micro- and nanomaterials increased the activity of cefotaxime against Staphylococcus aureus. ZSM-5 increased the activity of cefotaxime and ceftriaxone and Fe(3)O(4)/C(12) that of ceftriaxone against Pseudomonas aeruginosa and S. aureus. The anti-Pseudomonas, anti-Klebsiella pneumoniae and anti-Bacillus subtilis activity of cefoperazone was increased by Fe(3)O(4)/C(12) nanoparticles, while the ZSM-5 improved its anti-Escherichia coli, K. pneumoniae, S. aureus and B. subtilis activity, whereas Fe(3)O(4)/PEG(600) against K. pneumoniae. The anti-K. pneumoniae activity of cefepime was increased by all tested nanoparticles, whereas its anti-B. subtilis and anti-E. coli activity was improved by Fe(3)O(4)/C(12) and Fe(3)O(4)/PEG(600) nanoparticles. In conclusion, both magnetic Fe(3)O(4) nanoparticles, charged outside as extra-shell with the antibiotic as well as ZSM-5 microparticles carrying the antibiotic inside the pores, significantly and specifically improved cephalosporin efficacy. A probable explanation for the increase in the antibiotic efficiency is the better penetration through the cellular wall of the antibiotic charged nanoparticles. PMID:23101869

  4. High Speed SPM of Functional Materials

    SciTech Connect

    Huey, Bryan D.

    2015-08-14

    The development and optimization of applications comprising functional materials necessitates a thorough understanding of their static and dynamic properties and performance at the nanoscale. Leveraging High Speed SPM and concepts enabled by it, efficient measurements and maps with nanoscale and nanosecond temporal resolution are uniquely feasible. This includes recent enhancements for topographic, conductivity, ferroelectric, and piezoelectric properties as originally proposed, as well as newly developed methods or improvements to AFM-based mechanical, friction, thermal, and photoconductivity measurements. The results of this work reveal fundamental mechanisms of operation, and suggest new approaches for improving the ultimate speed and/or efficiency, of data storage systems, magnetic-electric sensors, and solar cells.

  5. Gen IV Materials Handbook Functionalities and Operation

    SciTech Connect

    Ren, Weiju

    2009-12-01

    This document is prepared for navigation and operation of the Gen IV Materials Handbook, with architecture description and new user access initiation instructions. Development rationale and history of the Handbook is summarized. The major development aspects, architecture, and design principles of the Handbook are briefly introduced to provide an overview of its past evolution and future prospects. Detailed instructions are given with examples for navigating the constructed Handbook components and using the main functionalities. Procedures are provided in a step-by-step fashion for Data Upload Managers to upload reports and data files, as well as for new users to initiate Handbook access.

  6. Research unit INTERNANO: Mobility, aging and functioning of engineered inorganic nanoparticles at the aquatic-terrestrial interface

    NASA Astrophysics Data System (ADS)

    Schaumann, Gabriele Ellen; Metreveli, George; Baumann, Thomas; Klitzke, Sondra; Lang, Friederike; Manz, Werner; Nießner, Reinhard; Schulz, Ralf; Vogel, Hans-Jörg

    2013-04-01

    Engineered inorganic nanoparticles (EINP) are expected to pass the wastewater-river-topsoil-groundwater pathway. Despite their increasing release, the processes governing the EINP aging and the changes in functionality in the environment are up to now largely unknown. The objective of the interdisciplinary research unit INTERNANO funded by the DFG is to identify the processes relevant for the fate of EINP and EINP-associated pollutants in the interfacial zone between aquatic and terrestrial ecosystems. The research unit consists of six subprojects and combines knowledge from aquatic and terrestrial sciences as well as from microbiology, ecotoxicology, physicochemistry, soil chemistry and soil physics. For the identification of key processes we will consider compartment specific flow conditions, physicochemistry and biological activity. Situations representative for a floodplain system are simulated using micromodels (?m scale) as well as incubation, soil column and joint laboratory stream microcosm experiments. These results will be transferred to a joint aquatic-terrestrial model system on EINP aging, transport and functioning across the aquatic-terrestrial transition zone. EINP isolation and characterization will be carried out via a combination of chromatographic, light scattering and microscopic methods including dynamic light scattering, elemental analysis, hydrodynamic radius chromatography, field flow fractionation as well as atomic force microscopy, Raman microscopy and electron microscopy. INTERNANO generates fundamental aquatic-terrestrial process knowledge, which will help to evaluate the environmental significance of the EINP at aquatic-terrestrial interfaces. Thus, INTERNANO provides a scientific basis to assess and predict the environmental impact of EINP release into the environment.

  7. Relationships between functional traits and inorganic nitrogen acquisition among eight contrasting European grass species

    PubMed Central

    Grassein, Fabrice; Lemauviel-Lavenant, Servane; Lavorel, Sandra; Bahn, Michael; Bardgett, Richard D.; Desclos-Theveniau, Marie; Laîné, Philippe

    2015-01-01

    Backgrounds and Aims Leaf functional traits have been used as a basis to categoize plants across a range of resource-use specialization, from those that conserve available resources to those that exploit them. However, the extent to which the leaf functional traits used to define the resource-use strategies are related to root traits and are good indicators of the ability of the roots to take up nitrogen (N) are poorly known. This is an important question because interspecific differences in N uptake have been proposed as one mechanism by which species’ coexistence may be determined. This study therefore investigated the relationships between functional traits and N uptake ability for grass species across a range of conservative to exploitative resource-use strategies. Methods Root uptake of NH4+ and NO3–, and leaf and root functional traits were measured for eight grass species sampled at three grassland sites across Europe, in France, Austria and the UK. Species were grown in hydroponics to determine functional traits and kinetic uptake parameters (Imax and Km) under standardized conditions. Key Results Species with high specific leaf area (SLA) and shoot N content, and low leaf and root dry matter content (LDMC and RDMC, respectively), which are traits associated with the exploitative syndrome, had higher uptake and affinity for both N forms. No trade-off was observed in uptake between the two forms of N, and all species expressed a higher preference for NH4+. Conclusions The results support the use of leaf traits, and especially SLA and LDMC, as indicators of the N uptake ability across a broad range of grass species. The difficulties associated with assessing root properties are also highlighted, as root traits were only weakly correlated with leaf traits, and only RDMC and, to a lesser extent, root N content were related to leaf traits. PMID:25471096

  8. Two-dimensional optimization of material composition of functionally graded materials using meshless analyses

    E-print Network

    Vel, Senthil

    Two-dimensional optimization of material composition of functionally graded materials using to optimize the material composition for two model problems. In the first problem, we minimize the peak reserved. Keywords: Heterogeneous solid; FGM; Inhomogeneous composite material; Local composition control

  9. Assessment of renal function of workers simultaneously exposed to inorganic lead and cadmium

    SciTech Connect

    Buchet, J.P.; Roels, H.; Bernard, A. Jr.; Lauwerys, R.

    1981-05-01

    The renal function of a group of workers (n = 62) exposed simultaneously to lead and to cadmium was examined. The results were compared with those obtained in an earlier study of three groups of workers - one exposed to lead only, one exposed to cadmium only, and one not exposed to either of these metals (control group). No interaction between lead and cadmium is evidenced. The signs of renal dysfunction found in the group exposed simultaneously to lead and to cadmium can be ascribed to cadmium only. The results of this study have confirmed the authors' previous observations, that is, a moderate exposure to lead (plumbemia < 62 ..mu..g/100 ml and average duration of exposure = 13.2 years) does not seem to influence renal function; in adult male workers the critical levels of cadmium in blood and in urine are 1 ..mu..g/100 ml whole blood and 10 ..mu..g/g creatinine respectivly; the renal dysfunction induced by cadmium is both glomerular and tubular.

  10. Keggin type inorganic-organic hybrid material containing Mn(II) monosubstituted phosphotungstate and S-(+)-sec-butyl amine: Synthesis and characterization

    SciTech Connect

    Patel, Ketan; Patel, Anjali

    2012-02-15

    Graphical abstract: A new organic-inorganic hybrid material containing Keggin type manganese substituted phosphotungstate and S-(+)-sec-butyl amine was synthesized and systematically characterized. Highlights: Black-Right-Pointing-Pointer New hybrid material comprising Mn substituted phosphotungstate (PW{sub 11}Mn) and S-(+)-sec-butyl amine (SBA) was synthesized. Black-Right-Pointing-Pointer The spectral studies reveal the attachment of SBA to the PW{sub 11}Mn without any distortion of structure. Black-Right-Pointing-Pointer The synthesized material comprises chirality. Black-Right-Pointing-Pointer The synthesized hybrid material can be used as a heterogeneous catalyst for carrying out asymmetric synthesis. -- Abstract: A new inorganic-organic POM-based hybrid material comprising Keggin type mono manganese substituted phosphotungstate and enantiopure S-(+)-sec-butyl amine was synthesized in an aqueous media by simple ligand substitution method. The synthesized hybrid material was systematically characterized in solid as well as solution by various physicochemical techniques such as elemental analysis, TGA, UV-vis, FT-IR, ESR and multinuclear solution NMR ({sup 31}P, {sup 1}H, {sup 13}C). The presence of chirality in the synthesized material was confirmed by CD spectroscopy and polarimeter. The above study reveals the attachment of S-(+)-sec-butyl amine to Keggin type mono manganese substituted phosphotungstate through N {yields} Mn bond. It also indicates the retainment of Keggin unit and presence of chirality in the synthesized material. An attempt was made to use the synthesized material as a heterogeneous catalyst for carrying out aerobic asymmetric oxidation of styrene using molecular oxygen. The catalyst shows the potential of being used as a stable recyclable catalytic material after simple regeneration without significant loss in conversion.

  11. Functional materials for energy-efficient buildings

    NASA Astrophysics Data System (ADS)

    Ebert, H.-P.

    2015-08-01

    The substantial improving of the energy efficiency is essential to meet the ambitious energy goals of the EU. About 40% of the European energy consumption belongs to the building sector. Therefore the reduction of the energy demand of the existing building stock is one of the key measures to deliver a substantial contribution to reduce CO2-emissions of our society. Buildings of the future have to be efficient in respect to energy consumption for construction and operation. Current research activities are focused on the development of functional materials with outstanding thermal and optical properties to provide, for example, slim thermally superinsulated facades, highly integrated heat storage systems or adaptive building components. In this context it is important to consider buildings as entities which fulfill energy and comfort claims as well as aesthetic aspects of a sustainable architecture.

  12. Synthesis and Characterization of a Layered Manganese Oxide: Materials Chemistry for the Inorganic or Instrumental Methods Lab

    ERIC Educational Resources Information Center

    Ching, Stanton; Neupane, Ram P.; Gray, Timothy P.

    2006-01-01

    A three-week laboratory project involving synthesis and characterization of a layered manganese oxide provides an excellent vehicle for teaching important concepts of inorganic chemistry and instrumental methods related to non-molecular systems. Na-birnessite is an easily prepared manganese oxide with a 7 A interlayer spacing and Na[superscript +]…

  13. Functional organic materials for electronics industries

    NASA Technical Reports Server (NTRS)

    Shibayama, K.; Ono, H.

    1982-01-01

    Topics closely related with organic, high molecular weight material synthesis are discussed. These are related to applications such as display, recording, sensors, semiconductors, and I.C. correlation. New materials are also discussed. General principles of individual application are not included. Materials discussed include color, electrochromic, thermal recording, organic photoconductors for electrophotography, and photochromic materials.

  14. Graphene-templated directional growth of an inorganic nanowire

    NASA Astrophysics Data System (ADS)

    Lee, Won Chul; Kim, Kwanpyo; Park, Jungwon; Koo, Jahyun; Jeong, Hu Young; Lee, Hoonkyung; Weitz, David A.; Zettl, Alex; Takeuchi, Shoji

    2015-05-01

    Assembling inorganic nanomaterials on graphene is of interest in the development of nanodevices and nanocomposite materials, and the ability to align such inorganic nanomaterials on the graphene surface is expected to lead to improved functionalities, as has previously been demonstrated with organic nanomaterials epitaxially aligned on graphitic surfaces. However, because graphene is chemically inert, it is difficult to precisely assemble inorganic nanomaterials on pristine graphene. Previous techniques based on dangling bonds of damaged graphene, intermediate seed materials and vapour-phase deposition at high temperature, have only formed randomly oriented or poorly aligned inorganic nanostructures. Here, we show that inorganic nanowires of gold(I) cyanide can grow directly on pristine graphene, aligning themselves with the zigzag lattice directions of the graphene. The nanowires are synthesized through a self-organized growth process in aqueous solution at room temperature, which indicates that the inorganic material spontaneously binds to the pristine graphene surface. First-principles calculations suggest that this assembly originates from lattice matching and ? interaction to gold atoms. Using the synthesized nanowires as templates, we also fabricate nanostructures with controlled crystal orientations such as graphene nanoribbons with zigzag-edged directions.

  15. Potential of hybrid functionalized meso-porous materials for the separation and immobilization of radionuclides

    SciTech Connect

    Luca, V.

    2013-07-01

    Functionalized meso-porous materials are a class of hybrid organic-inorganic material in which a meso-porous metal oxide framework is functionalized with multifunctional organic molecules. These molecules may contain one or more anchor groups that form strong bonds to the pore surfaces of the metal oxide framework and free functional groups that can impart and or modify the functionality of the material such as for binding metal ions in solution. Such materials have been extensively studied over the past decade and are of particular interest in absorption applications because of the tremendous versatility in choosing the composition and architecture of the metal oxide framework and the nature of the functional organic molecule as well as the efficient mass transfer that can occur through a well-designed hierarchically porous network. A sorbent for nuclear applications would have to be highly selective for particular radio nuclides, it would need to be hydrolytically and radiolytically stable, and it would have to possess reasonable capacity and fast kinetics. The sorbent would also have to be available in a form suitable for use in a column. Finally, it would also be desirable if once saturated with radio nuclides, the sorbent could be recycled or converted directly into a ceramic or glass waste form suitable for direct repository disposal or even converted directly into a material that could be used as a transmutation target. Such a cradle-to- grave strategy could have many benefits in so far as process efficiency and the generation of secondary wastes are concerned.This paper will provide an overview of work done on all of the above mentioned aspects of the development of functionalized meso-porous adsorbent materials for the selective separation of lanthanides and actinides and discuss the prospects for future implementation of a cradle-to-grave strategy with such materials. (author)

  16. Electrophoretic forming of functionally-graded materials

    SciTech Connect

    Sarkar, P.; Datta, S.; Nicholson, P.S.

    1997-12-31

    Electrophoretic deposition (EPD) is a colloidal forming process where electrically charged particles are deposited onto an oppositely-charged electrode from an electrostatically stabilized suspension by the application of a dc electric field. It is a cheap and facile technique to fabricate complicated ceramic shapes. EPD is very effective method to synthesize ceramic/ceramic and metal/ceramic composites, eg.; dispersed, laminar, fibre reinforced, and functionally graded materials (FGM) etc. By EPD it is possible to synthesize step FGMs and continuous profile FGMs. The compositional profile of the FGM can be controlled by deposition current density, second component flow rate, suspension concentration etc. Step and continuous profile Al{sub 2}O{sub 3}/YSZ and continuous profile Al{sub 2}O{sub 3}/MoSi{sub 2}, Al{sub 2}O{sub 3}/Ni and YSZ/Ni fabrication is reported herein. The microstructures of the FGMs produced were characterized by optical/electron microscopy and micro-indentation was used to quantify the Vicker`s hardness and fracture toughness variation across The FGM sections.

  17. Enhancing the value of commodity polymers: Part 1. Structure-property relationships in composite materials based on maleated polypropylene/inorganic phosphate glasses. Part 2. New value-added applications for polyesters

    NASA Astrophysics Data System (ADS)

    Gupta, Mohit

    The first part of the thesis (Chapters 2 & 3) describes a new class of organic polymer/inorganic glass composite materials with property improvements that are impossible to achieve with classical polymer blends or composites. These materials exhibit good processability, superior mechanical performance, good thermal stability, and have excellent gas barrier properties. Low glass transition temperature phosphate glasses (Pglass) are used as inorganic fillers and slightly maleated polypropylene is used as the organic polymer matrix. The Pglass, which was dispersed as spherical droplets in the unoriented composites can be elongated into high aspect ratio platelets during the biaxial stretching process. Biaxially oriented films exhibited a brick wall type microstructure with highly aligned inorganic platelets in a ductile organic matrix and the oxygen barrier properties are significantly improved due to presence of Pglass platelets as impermeable inclusions. Mechanical properties of the biaxially oriented films showed significant improvements compared to neat polymer due to uniform dispersion of the Pglass platelets. Properly dispersed and aligned platelets have proven to be very effective for increasing the composite modulus. These developed materials therefore show promise to help fulfill the ever increasing demand for new advanced materials for a wide variety of advanced packaging applications because of their gas barrier properties, flexibility, transparency, mechanical strength and performance under humid conditions. The second part of the thesis (Chapters 4 & 5) describes new value-added applications for polyesters. Chapter 4 reports a novel process for the decolorization of green and blue colored PET bottle flakes using hydrogen peroxide. The decolorized flakes were characterized for color, intrinsic viscosity values. Decolorized flakes exhibited color values similar to those of colorless recycled PET and even though IV values decreased, bleached flakes still exhibit useful molecular weight. The consumption of H2O2 during the bleaching process was quantified by titrating the residual peroxide using a standard solution of potassium permanganate. Chapter 5 reports synthesis of ductile amorphous polymers which change their color as a function of mechanical deformation. Cyano--OPV moieties were covalently incorporated into the backbone of amorphous polyester PETG. The materials exhibit a significant color change upon compression consistent with efficient breakup of the dye aggregates upon deformation and therefore can be useful for technological applications that require smart coatings with integrated scratch detectors.

  18. Arsenic, inorganic

    Integrated Risk Information System (IRIS)

    Arsenic , inorganic ; CASRN 7440 - 38 - 2 Human health assessment information on a chemical substance is included in the IRIS database only after a comprehensive review of toxicity data , as outlined in the IRIS assessment development process . Sections I ( Health Hazard Assessments for Noncarcinoge

  19. UCSB Materials Colloquium 4/16/2010 Compositional tuning of functional inorganic

    E-print Network

    Bigelow, Stephen

    Colloquium 4/16/2010 The Chanel Building in Osaka (Peter Marino Architect). LED lamps for indoor cultivation/16/2010 Garnet crystal structure: AlO4 tetrahedra and AlO6 octahedra, all completely corner- connected. Y

  20. Electrospinning of functional materials for biomedicine and tissue engineering

    NASA Astrophysics Data System (ADS)

    Inozemtseva, O. A.; Salkovskiy, Y. E.; Severyukhina, A. N.; Vidyasheva, I. V.; Petrova, N. V.; Metwally, H. A.; Stetciura, I. Y.; Gorin, D. A.

    2015-03-01

    Published data on nanostructured materials prepared by electrospinning are analyzed and generalized. Particular attention is devoted to the design and properties of nanocomposite fibrous materials and methods for modification and functionalization of fibre surface. The prospects for the application of non-woven materials for biotissue engineering and for the development of smart materials are considered. The bibliography includes 330 references.

  1. Determination of Organic and Inorganic Percentages and Mass of Suspended Material at Four Sites in the Illinois River in Northwestern Arkansas and Northeastern Oklahoma, 2005-07

    USGS Publications Warehouse

    Galloway, Joel M.

    2008-01-01

    The Illinois River located in northwestern Arkansas and northeastern Oklahoma is influenced by point and nonpoint sources of nutrient enrichment. This has led to increased algal growth within the stream, reducing water clarity. Also, sediment runoff from fields, pastures, construction sites, and other disturbed areas, in addition to frequent streambank failure, has increased sedimentation within the stream and decreased water clarity. A study was conducted by the U.S. Geological Survey in cooperation with the Arkansas Department of Environmental Quality and the U.S. Environmental Protection Agency to characterize the increased turbidity by determining the organic and inorganic composition and mass of suspended material in the Illinois River from August 2005 through July 2007. Water-quality samples were collected at four sites on the Illinois River (listed in downstream order): near Viney Grove, Arkansas; at Savoy, Arkansas; south of Siloam Springs, Arkansas; and near Tahlequah, Oklahoma. In general, turbidity, total suspended solids, suspended-sediment concentration, organic material concentration (measured as volatile suspended solids and ash-free dry mass), and chlorophyll a concentration were the greatest in samples collected from the Illinois River at Savoy and the least in samples from the most upstream Illinois River site (near Viney Grove) and the most downstream site (near Tahlequah) from August 2005 through July 2007. For example, the suspended-sediment concentration at the Illinois River at Savoy had a median of 15 milligrams per liter, and the total suspended solids had a median of 12 milligrams per liter. The Illinois River near Tahlequah had the least suspended-sediment concentration with a median of 10 milligrams per liter and the least total suspended solids with a median of 6 milligrams per liter. The turbidity, total suspended solids, suspended-sediment concentration, organic material concentration, and chlorophyll a concentration in samples collected during high-flow events were greater than in samples collected during base-flow conditions at the Illinois River at Savoy, south of Siloam Springs, and near Tahlequah. For example, the median turbidity for the Illinois River at Savoy was 3 nephelometric turbidity ratio units during base-flow conditions and 52 nephelometric turbidity ratio units during high-flow conditions. Organic material in the Illinois River generally composed between 13 and 47 percent of the total suspended material in samples collected from August 2005 through July 2007. Therefore, most of the suspended material in samples collected from the sites was inorganic material. Overall, the highest percentage of organic material was found at the Illinois River near Viney Grove and at the Illinois River near Tahlequah. The Illinois River south of Siloam Springs had the lowest percentage of organic material among the four sites. In general, the percentage of organic material was greater in samples collected during base-flow conditions compared to samples collected during high-flow conditions. The mean seasonal concentrations and percentages of organic material were the least in the fall (September through November) in samples collected from August 2005 to July 2007 from the four Illinois River sites, while the greatest concentrations and percentages of organic material occurred at various times of the year depending on the site. The greatest concentrations of organic material occurred in the summer (June through August) in samples from sites on the Illinois River near Viney Grove, at Savoy and south of Siloam Springs, but in the spring (March through May) in samples from the Illinois River near Tahlequah. The greatest percentages of organic material (least percentages of inorganic material) occurred in the summer in samples from the site near Viney Grove, the winter and summer at the site at Savoy, in the spring, fall, and winter (December through February) at the site south of Siloam Springs, an

  2. Biomineralized structural materials with functional optical properties

    E-print Network

    Li, Ling, Ph. D. Massachusetts Institute of Technology

    2014-01-01

    Many biological structural materials exhibit "mechanical property amplification" through their intricate hierarchical composite designs. In the past several decades, significant progress has been achieved in elucidating ...

  3. Nanocomposites of polymer and inorganic nanoparticles for optical and magnetic applications

    PubMed Central

    Li, Shanghua; Meng Lin, Meng; Toprak, Muhammet S.; Kim, Do Kyung; Muhammed, Mamoun

    2010-01-01

    This article provides an up-to-date review on nanocomposites composed of inorganic nanoparticles and the polymer matrix for optical and magnetic applications. Optical or magnetic characteristics can change upon the decrease of particle sizes to very small dimensions, which are, in general, of major interest in the area of nanocomposite materials. The use of inorganic nanoparticles into the polymer matrix can provide high-performance novel materials that find applications in many industrial fields. With this respect, frequently considered features are optical properties such as light absorption (UV and color), and the extent of light scattering or, in the case of metal particles, photoluminescence, dichroism, and so on, and magnetic properties such as superparamagnetism, electromagnetic wave absorption, and electromagnetic interference shielding. A general introduction, definition, and historical development of polymer–inorganic nanocomposites as well as a comprehensive review of synthetic techniques for polymer–inorganic nanocomposites will be given. Future possibilities for the development of nanocomposites for optical and magnetic applications are also introduced. It is expected that the use of new functional inorganic nano-fillers will lead to new polymer–inorganic nanocomposites with unique combinations of material properties. By careful selection of synthetic techniques and understanding/exploiting the unique physics of the polymeric nanocomposites in such materials, novel functional polymer–inorganic nanocomposites can be designed and fabricated for new interesting applications such as optoelectronic and magneto-optic applications. PMID:22110855

  4. Designing conjugated polymer-based functional materials via the incorporation of supramolecular complexities

    E-print Network

    Kwan, Phoebe Hoi-Ying, 1978-

    2005-01-01

    One of the major goals in molecule engineering is the creation of molecule- or polymer- based devices that mimic the integrated functions of their macroscopic (and often inorganic) counterparts. Because of their unique ...

  5. Density functional theory in materials science

    PubMed Central

    Neugebauer, Jörg; Hickel, Tilmann

    2013-01-01

    Materials science is a highly interdisciplinary field. It is devoted to the understanding of the relationship between (a) fundamental physical and chemical properties governing processes at the atomistic scale with (b) typically macroscopic properties required of materials in engineering applications. For many materials, this relationship is not only determined by chemical composition, but strongly governed by microstructure. The latter is a consequence of carefully selected process conditions (e.g., mechanical forming and annealing in metallurgy or epitaxial growth in semiconductor technology). A key task of computational materials science is to unravel the often hidden composition–structure–property relationships using computational techniques. The present paper does not aim to give a complete review of all aspects of materials science. Rather, we will present the key concepts underlying the computation of selected material properties and discuss the major classes of materials to which they are applied. Specifically, our focus will be on methods used to describe single or polycrystalline bulk materials of semiconductor, metal or ceramic form. PMID:24563665

  6. Investigations of inorganic and hybrid inorganic-organic nanostructures

    NASA Astrophysics Data System (ADS)

    Kam, Kinson Chihang

    This thesis focuses on the exploratory synthesis and characterization of inorganic and hybrid inorganic-organic nanomaterials. In particular, nanostructures of semiconducting nitrides and oxides, and hybrid systems of nanowire-polymer composites and framework materials, are investigated. These materials are characterized by a variety of techniques for structure, composition, morphology, surface area, optical properties, and electrical properties. In the study of inorganic nanomaterials, gallium nitride (GaN), indium oxide (In2O3), and vanadium dioxide (VO2) nanostructures were synthesized using different strategies and their physical properties were examined. GaN nanostructures were obtained from various synthetic routes. Solid-state ammonolysis of metastable gamma-Ga2O 3 nanoparticles was found to be particularly successful; they achieved high surface areas and photoluminescent study showed a blue shift in emission as a result of surface and size defects. Similarly, In2O3 nanostructures were obtained by carbon-assisted solid-state syntheses. The sub-oxidic species, which are generated via a self-catalyzed vapor-liquid-solid mechanism, resulted in 1D nanostructures including nanowires, nanotrees, and nanobouquets upon oxidation. On the other hand, hydrothermal methods were used to obtain VO2 nanorods. After post-thermal treatment, infrared spectroscopy demonstrated that these nanorods exhibit a thermochromic transition with temperature that is higher by ˜10°C compared to the parent material. The thermochromic behavior indicated a semiconductor-to-metal transition associated with a structural transformation from monoclinic to rutile. The hybrid systems, on the other hand, enabled their properties to be tunable. In nanowire-polymer composites, zinc oxide (ZnO) and silver (Ag) nanowires were synthesized and incorporated into polyaniline (PANI) and polypyrrole (PPy) via in-situ and ex-situ polymerization method. The electrical properties of these composites are significantly influenced by the nanowire-polymer ratios and chemical functionalization of the respective nanowires, up to an order of magnitude. In hybrid framework materials, nine novel phases of magnesium tartrate coordination polymers were synthesized by exploiting different analogs of tartaric acid, resulting in chiral and achiral frameworks. These phases exhibited a diverse range of structures as a result of connectivity, density, composition differences as a function of temperature. The chirality of some of these frameworks was also verified using circular dichroism.

  7. Mussel-inspired functionalization of graphene for synthesizing Ag-polydopamine-graphene nanosheets as antibacterial materials

    NASA Astrophysics Data System (ADS)

    Zhang, Zhe; Zhang, Jing; Zhang, Bailin; Tang, Jilin

    2012-12-01

    Mussels have been shown to attach to virtually all types of inorganic and organic surfaces via their adhesive proteins. The adhesive proteins secreted by mussels contain high concentrations of catechol and amine functional groups, which have similar functional groups with polydopamine (PDA). Inspired by mussels, a mild and environmentally friendly method was used to synthesize Ag nanoparticles (Ag NPs) on functionalized PDA-graphene nanosheets (PDA-GNS) with uniform and high dispersion. First, a uniform layer of PDA was coated on graphene oxide (GO) by polymerizing dopamine (DA) at room temperature. During the process GO was reduced by the DA. The PDA layer on the surface of GNS can be used as a nanoscale guide to form uniform Ag NPs on the surface of PDA-GNS. The obtained Ag-PDA-GNS hybrid materials are characterized by atomic force microscopy, transmission electron microscopy, UV-vis spectroscopy, Raman spectroscopy, X-ray photo-electron spectroscopy, X-ray diffraction, and thermal gravimetric analysis. The resultant Ag-PDA-GNS hybrid materials exhibited strong antibacterial properties to both Gram-negative and Gram-positive bacteria due to the synergistic effect of GNS and Ag NPs.Mussels have been shown to attach to virtually all types of inorganic and organic surfaces via their adhesive proteins. The adhesive proteins secreted by mussels contain high concentrations of catechol and amine functional groups, which have similar functional groups with polydopamine (PDA). Inspired by mussels, a mild and environmentally friendly method was used to synthesize Ag nanoparticles (Ag NPs) on functionalized PDA-graphene nanosheets (PDA-GNS) with uniform and high dispersion. First, a uniform layer of PDA was coated on graphene oxide (GO) by polymerizing dopamine (DA) at room temperature. During the process GO was reduced by the DA. The PDA layer on the surface of GNS can be used as a nanoscale guide to form uniform Ag NPs on the surface of PDA-GNS. The obtained Ag-PDA-GNS hybrid materials are characterized by atomic force microscopy, transmission electron microscopy, UV-vis spectroscopy, Raman spectroscopy, X-ray photo-electron spectroscopy, X-ray diffraction, and thermal gravimetric analysis. The resultant Ag-PDA-GNS hybrid materials exhibited strong antibacterial properties to both Gram-negative and Gram-positive bacteria due to the synergistic effect of GNS and Ag NPs. Electronic supplementary information (ESI) available. See DOI: 10.1039/c2nr32092d

  8. Synthesis and structural characterization of a new chiral porous hybrid organic–inorganic material based on ?-zirconium phosphates and L-(+)-phosphoserine

    SciTech Connect

    Alhendawi, Hussein M.H.

    2013-05-01

    In the present work, a chiral layered derivative of ?-zirconium phosphate (?-ZrP) containing L-(+)-phosphoserine (?-ZrP-PS*) covalently attached to inorganic layers has been prepared by means of topotactic exchange reaction. This organic–inorganic derivative is characterized by X-ray diffractometry, Solid {sup 13}C–NMR and FT-IR spectrophotometries and thermal analyses. A maximum level of topotactic replacement of 20% is achieved. Under both the acidic environment of the interlayer region of ?-ZrP and the acidic synthesis conditions, the hydrolysis of the ester bond of PS* is expected to take place to some extent. For this reason, it was impossible to exceed the recent percentage, which in turn reflects the relative moderate stability of the above mentioned bond under these conditions. In order to be more certain with regard to an expected further hydrolysis for this bond after separation, a sample of ?-ZrP-PS* was stored in a desiccator over a saturated solution of BaCl{sub 2} (90% relative humidity) for three months, and then the sample re-analyzed once again. Surprisingly, the results show that the sample still keeps almost the same level of exchange (i.e., 20%). Second, it is revealed that the sample almost gives the same spectroscopic and thermal behavior. This could be attributed to the less acidic character of the partially exchanged inorganic layers of the sample in comparison with that of the precursor ?-ZrP. Therefore, the PS* molecules persist and stay there into the interlayer gallery without further hydrolysis. - Graphical abstract: • Red: oxygen • White: zirconium • Cyan: carbon • Yellow: phosphorus • Blue: nitrogen. Highlights: • L-(+)-Phosphoserine (PS*) is exchanged with ?-ZrP by means of topotactic exchange. • The maximum exchange level is 20%. • ?-ZrP is functionalized with chiral amino acid group. • ?-ZrP-PS* has large chiral space for huge guest molecules to be intercalated.

  9. Förster resonant energy transfer from an inorganic quantum well to a molecular material: Unexplored aspects, losses, and implications to applications.

    PubMed

    Itskos, G; Othonos, A; Choulis, S A; Iliopoulos, E

    2015-12-01

    A systematic investigation of Förster resonant energy transfer (FRET) is reported within a hybrid prototype structure based on nitride single quantum well (SQW) donors and light emitting polymer acceptors. Self-consistent Schrödinger-Poisson modeling and steady-state and time-resolved photoluminescence experiments were initially employed to investigate the influence of a wide structural parameter space on the emission quantum yield of the nitride component. The optimized SQW heterostructures were processed into hybrid structures with spin-casted overlayers of polyfluorenes. The influence of important unexplored aspects of the inorganic heterostructure such as SQW confinement, content, and doping on the dipole-dipole coupling was probed. Competing mechanisms to the FRET process associated with interfacial recombination and charge transfer have been studied and their implications to device applications exploiting FRET across heterointerfaces have been discussed. PMID:26646883

  10. Ion-Conducting Organic/Inorganic Polymers

    NASA Technical Reports Server (NTRS)

    Kinder, James D.; Meador, Mary Ann B.

    2007-01-01

    Ion-conducting polymers that are hybrids of organic and inorganic moieties and that are suitable for forming into solid-electrolyte membranes have been invented in an effort to improve upon the polymeric materials that have been used previously for such membranes. Examples of the prior materials include perfluorosulfonic acid-based formulations, polybenzimidazoles, sulfonated polyetherketone, sulfonated naphthalenic polyimides, and polyethylene oxide (PEO)-based formulations. Relative to the prior materials, the polymers of the present invention offer greater dimensional stability, greater ease of formation into mechanically resilient films, and acceptably high ionic conductivities over wider temperature ranges. Devices in which films made of these ion-conducting organic/inorganic polymers could be used include fuel cells, lithium batteries, chemical sensors, electrochemical capacitors, electrochromic windows and display devices, and analog memory devices. The synthesis of a polymer of this type (see Figure 1) starts with a reaction between an epoxide-functionalized alkoxysilane and a diamine. The product of this reaction is polymerized by hydrolysis and condensation of the alkoxysilane group, producing a molecular network that contains both organic and inorganic (silica) links. The silica in the network contributes to the ionic conductivity and to the desired thermal and mechanical properties. Examples of other diamines that have been used in the reaction sequence of Figure 1 are shown in Figure 2. One can use any of these diamines or any combination of them in proportions chosen to impart desired properties to the finished product. Alternatively or in addition, one could similarly vary the functionality of the alkoxysilane to obtain desired properties. The variety of available alkoxysilanes and diamines thus affords flexibility to optimize the organic/inorganic polymer for a given application.

  11. Inorganic salts interact with oxalic acid in submicron particles to form material with low hygroscopicity and volatility

    NASA Astrophysics Data System (ADS)

    Drozd, G.; Woo, J.; Häkkinen, S. A. K.; Nenes, A.; McNeill, V. F.

    2014-05-01

    Volatility and hygroscopicity are two key properties of organic aerosol components, and both are strongly related to chemical identity. While the hygroscopicities of pure salts, di-carboxylic acids (DCA), and DCA salts are known, the hygroscopicity of internal mixtures of these components, as they are typically found in the atmosphere, has not been fully characterized. Here we show that inorganic-organic component interactions typically not considered in atmospheric models can lead to very strongly bound metal-organic complexes and greatly affect aerosol volatility and hygroscopicity; in particular, the bi-dentate binding of DCA to soluble inorganic ions. We have studied the volatility of pure, dry organic salt particles and the hygroscopicity of internal mixtures of oxalic acid (OxA, the dominant DCA in the atmosphere) and a number of salts, both mono- and di-valent. The formation of very low volatility organic salts was confirmed, with minimal evaporation of oxalate salt particles below 75 °C. Dramatic increases in the cloud condensation nuclei (CCN) activation diameter for particles with di-valent salts (e.g., CaCl2) and relatively small particle volume fractions of OxA indicate that standard volume additivity rules for hygroscopicity do not apply. Thus small organic compounds with high O : C ratios are capable of forming low-volatility and very low hygroscopicity particles. Given current knowledge of the formation mechanisms of OxA and M-Ox salts, surface enrichment of insoluble M-Ox salts is expected. The resulting formation of an insoluble coating of metal-oxalate salts can explain low-particle hygroscopicities. The formation of particles with a hard coating could offer an alternative explanation for observations of glass-like particles without the need for a phase transition.

  12. Measuring oxygen yields of a thermal conversion/elemental analyzer-isotope ratio mass spectrometer for organic and inorganic materials through injection of CO.

    PubMed

    Yin, Xijie; Chen, Zhigang

    2014-12-01

    The thermal conversion/elemental analyzer-isotope ratio mass spectrometer (TC/EA-IRMS) is widely used to measure the ?(18) O value of various substances. A premise for accurate ?(18) O measurement is that the oxygen in the sample can be converted into carbon monoxide (CO) quantitatively or at least proportionally. Therefore, a precise method to determine the oxygen yield of TC/EA-IRMS measurements is needed. Most studies have used the CO peak area obtained from a known amount of a solid reference material (for example, benzoic acid) to calibrate the oxygen yield of the sample. Although it was assumed that the oxygen yield of the solid reference material is 100%, no direct evidence has been provided. As CO is the analyte gas for ?(18) O measurement by IRMS, in this study, we use a six-port valve to inject CO gas into the TC/EA. The CO is carried to the IRMS by the He carrier gas and the CO peak area is measured by the IRMS. The CO peak area thus obtained from a known amount of the injected CO is used to calibrate the oxygen yield of the sample. The oxygen yields of commonly used organic and inorganic reference materials such as benzoic acid (C6 H5 COOH), silver phosphate (Ag3 PO4 ), calcium carbonate (CaCO3 ) and silicon dioxide (SiO2 ) are investigated at different reactor temperatures and sample sizes. We obtained excellent linear correlation between the peak area for the injected CO and its oxygen atom amount. C6 H5 COOH has the highest oxygen yield, followed by Ag3 PO4 , CaCO3 and SiO2 . The oxygen yields of TC/EA-IRMS are less than 100% for both organic and inorganic substances, but the yields are relatively stable at the specified reactor temperature and for a given quantity of sample. PMID:25476948

  13. Direct determination of methylmercury and inorganic mercury in biological materials by solid sampling-electrothermal vaporization-inductively coupled plasma-isotope dilution-mass spectrometry.

    PubMed

    Gelaude, I; Dams, R; Resano, M; Vanhaecke, F; Moens, L

    2002-08-01

    This paper reports on the use of solid sampling-electrothermal vaporization-inductively coupled plasma mass spectrometry (SS-EIV-ICPMS) for the direct and simultaneous determination of methylmercury and inorganic mercury in biological materials. The main advantage of this fast and sensitive method is that no sample preparation is required. In this way, the sample throughput can be considerably increased, problems of contamination and analyte losses are kept to a minimum and, even more important, the original chemical form of the different analyte species in the solid samples is preserved. To achieve this goal, a solid sample is inserted into a graphite furnace of the boat-in-tube type and is subsequently submitted to an appropriate temperature program, leading to the separate vaporization of methylmercury and inorganic mercury, which are transported into the ICP by means of an argon carrier gas. The separation was accomplished within 75 s. For the quantification of the two peaks, species-unspecific isotope dilution was used. For this purpose, a stable flow of argon loaded with gaseous Hg isotopically enriched in 200Hg was generated using a permeation tube that was constructed in-house. Its emission rate was determined by collecting the mercury released during a given time interval on a gold-coated silica absorber, after which the amount collected was released by heating of the absorber and determined by cold vapor atomic absorption spectrometry (CVAAS) and cold vapor atomic fluorescence spectrometry (CVAFS). A reference material from the Canadian National Research Council (NRC) (TORT-2) was used to assess the accuracy of the method. For the application of the method to samples with diverse mercury contents, the spike/sample ratio can be optimized by varying the emission rate of the permeation tube simply by adapting its temperature. To prove the feasibility of this approach, two reference materials (BCR 463 and DORM-2) with a methylmercury content more than 10 times higher than that of TORT-2 were also analyzed. The detection limits obtained for 1 mg of sample (2 ng g(-1) and 6 ng g(-1) for methylmercury and inorganic mercury, respectively) were found to be sufficiently low for this kind of application and are competitive when compared to other techniques. PMID:12175173

  14. FUNCTIONAL AND SMART MATERIALS -Structural evolution and structure analysis

    E-print Network

    Wang, Zhong L.

    of functioning of a Turning machine. A smart material is a physical structure having (i) a definite purpose, (ii are a new emerging materials system which combines contemporary materials science with information science and repetivity. A smart system/structure is defined to be a non-biological physical structure having

  15. One-dimensional magnetic inorganic-organic hybrid nanomaterials.

    PubMed

    Yuan, Jiayin; Xu, Youyong; Müller, Axel H E

    2011-02-01

    One-dimensional (1D) magnetic inorganic-organic hybrid nanomaterials bear both the intrinsic magnetic properties of the inorganic components and the functionality and responsiveness of their organic part. In this tutorial review, we first emphasize various synthetic strategies for this type of materials: (i) template-directed synthesis employs different preformed templates such as channels in solids, mesostructures self-assembled from block copolymers, cylindrical polymer brushes, 1D biological templates and other existing 1D templates; (ii) electrospinning, which provides a simple and efficient technique that can lead to a potential large-scale production; (iii) 1D conjugation of building blocks which combines the physical attraction of magnetic nanoparticles in a magnetic field with chemical crosslinking and stabilization. The properties, functions and the future trends of these materials are also briefly introduced. It is foreseeable that these hybrid materials will play more and more important roles in the ever-advancing miniaturization of functional devices. PMID:21206943

  16. Printing Functional Materials Jennifer A. Lewis

    E-print Network

    D Printer: Fused deposition modeling of molten ink filaments Z-Corp 3D Printer: Inkjet printing on powder bed Urbee car POPSCI 11.01.10 #12;Several advances needed for 3-D printing of high transformation from rapid prototyping to manufacturing of advanced materials #12;! ink

  17. The Materials genome : rapid materials screening for renewable energy using high-throughput density functional theory

    E-print Network

    Jain, Anubhav, Ph.D. Massachusetts Institute of Technology

    2011-01-01

    This thesis relates to the emerging field of high-throughput density functional theory (DFT) computation for materials design and optimization. Although highthroughput DFT is a promising new method for materials discovery, ...

  18. PREFACE: Annual Conference on Functional Materials and Nanotechnologies - FM&NT 2011

    NASA Astrophysics Data System (ADS)

    Sternberg, Andris; Muzikante, Inta; Zicans, Janis

    2011-06-01

    The International Conference Functional Materials and Nanotechnologies (FM&NT-2011) was held in Riga, 5-8 April 2011 in the Institute of Solid State Physics, University of Latvia (ISSP LU). The conference was organized in co-operation with projects ERANET 'MATERA' and National Research programme in Materials Science and Information Technologies. The purpose of the conference was to bring together scientists, engineers and students from universities, research institutes and related industrial companies active in the field of advanced material science and materials technologies trends and future activities. Scientific themes covered in the conference are: theoretical research and modelling of processes and materials; materials for energetics, renewable energy technologies and phtovoltaics; multifunctional inorganic, organic and hybrid materials for photonic, micro and nanoelectronic applications and innovative methods for research of nanostructures; advanced technologies for synthesis and research of nanostructured materials, nanoparticles, thin films and coatings; application of innovative materials in science and economics. The number of registered participants from 17 countries was nearly 300. During three days of the conference 22 invited, 69 oral reports and 163 posters were presented. 40 papers, based on these reports, are included in this volume of IOP Conference Series: Materials Science and Engineering. Additional information about FM&NT-2011 is available in its homepage http://www.fmnt.lu.lv. The Organizing Committee would like to thank all speakers, contributors, session chairs, referees and meeting staff for their efforts in making the FM&NT-2011 successful. The Organizing Committee sincerely hopes that that the conference gave all participants new insights into the widespread development of functional materials and nanotechnologies and would enhance the circulation of information released at the meeting. Andris Sternberg Inta Muzikante Janis Zicans Conference photograph ERAF logo International Organizing Committee Andris Sternberg (chairperson), Institute of Solid State Physics, University of Latvia, Latvia, MATERA Juras Banys, Vilnius University, Lithuania Gunnar Borstel, University of Osnabrück, Germany Niels E Christensen, University of Aarhus, Denmark Robert A Evarestov, St. Petersburg State University, Russia Claes-Goran Granqvist, Uppsala University, Sweden Dag Høvik, The Research Council of Norway, Norway, MATERA Marco Kirm, Institute of Physics, University of Tartu, Estonia Vladislav Lemanov, Ioffe Physical Technical Institute, Russia Witold Lojkowski, Institute of High Pressure Physics, Poland Ergo Nommiste, University of Tartu, Estonia Helmut Schober, Institut Laue-Langevin, France Sisko Sipilä, Finnish Funding Agency for Technology and Innovation, Finland, MATERA Ingólfur Torbjörnsson, Icelandic Centre for Research, Iceland, MATERA Marcel H Van de Voorde, University of Technology Delft, The Netherlands International Program Committee Inta Muzikante (chairperson), Institute of Solid State Physics, University of Latvia, Latvia, MATERA Liga Berzina-Cimdina, Institute of Biomaterials and Biomechanics, Riga Technical University, Latvia Janis Grabis, Institute of Inorganic Chemistry, Riga Technical University, Latvia Leonid V Maksimov, Vavilov State Optical Institute, Russia Linards Skuja, Institute of Solid State Physics, University of Latvia, Latvia Maris Springis, Institute of Solid State Physics, University of Latvia, Latvia Ilmars Zalite, Institute of Inorganic Chemistry, Riga Technical University, Latvia Janis Zicans, Institute of Polymers, Riga Technical University Local Committee: Liga Grinberga, Anatolijs Sarakovskis, Jurgis Grube, Raitis Siatkovskis, Maris Kundzins, Anna Muratova, Maris Springis, Aivars Vembris, Krisjanis Smits, Andris Fedotovs, Dmitrijs Bocarovs, Anastasija Jozepa, Andris Krumins.

  19. Design and Simulation of 2×2 MMI Coupler and Thermo-optic Switch Using Sol-Gel Derived Organic-Inorganic Hybrid Material

    NASA Astrophysics Data System (ADS)

    Samah, M. Firdaus A.; Nawabjan, Amirjan; Abdullah, Ahmad Sharmi; Ibrahim, Mohd Haniff; Kassim, Norazan Mohd; Mohamad, Abu Bakar

    2011-05-01

    A new design of Multimode Interference (MMI) thermo-optic switch with improved crosstalk figure is demonstrated in this paper. The device is designed and simulated using BeamProp 3D from Rsoft and 3D BPM CAD softwares. The devices are designed based on sol-gel derived organic-inorganic hybrid material, vinyltriethoxysilane (VTES), tetraethoxysilane (TEOS) and tetrabutoxytitanate (TTBu) or VTT with refractive index of 1.47 as a core and surrounded by silica with refractive index of 1.45 at 1550 nm wavelength. The switching power is 164mW and the simulation result show that the propagation loss of the MMI device is 1.8 dB and zero crosstalk.

  20. Sequential structural transitions with distinct dielectric responses in a layered perovskite organic-inorganic hybrid material: [C4H9N]2[PbBr4].

    PubMed

    Wang, Zhong-Xia; Liao, Wei-Qiang; Ye, Heng-Yun; Zhang, Yi

    2015-12-21

    A novel organic-inorganic hybrid layered perovskite-type compound of the general formula A2BX4, bis(IBA)tetrabromolead(ii) (1, IBA = isobutyl-ammonium cation), has been successfully synthesized and grown as flake-like crystals, and undergoes two reversible solid-state phase transitions at 315 K and 250 K, and has been systematically characterized using differential scanning calorimetry measurements, variable-temperature structural analyses, variable-temperature powder X-ray diffraction measurements and dielectric measurements. 1 exhibits a remarkable temperature-dependent dielectric behavior, which could be switched between high and low dielectric states above room temperature, and a broad peak exists below room temperature. The most striking dielectric property is the remarkable anisotropy along the various crystallographic axes. All of these demonstrate its potential application as a high temperature switchable molecular dielectric and low temperature phase transition material. PMID:26503162

  1. Advanced Functional Materials for Energy Related Applications

    NASA Astrophysics Data System (ADS)

    Sasan, Koroush

    The current global heavy dependency on fossil fuels gives rise to two critical problems: I) fossil fuels will be depleted in the near future; II) the release of green house gas CO2 generated by the combustion of fossil fuels contributes to global warming. To potentially address both problems, this dissertation documents three primary areas of investigation related to the development of alternative energy sources: electrocatalysts for fuel cells, photocatalysts for hydrogen generation, and photoreduction catalysts for converting CO2 to CH4. Fuel cells could be a promising source of alternative energy. Decreasing the cost and improving the durability and power density of Pt/C as a catalyst for reducing oxygen are major challenges for developing fuel cells. To address these concerns, we have synthesized a Nitrogen-Sulfur-Iron-doped porous carbon material. Our results indicate that the synthesized catalyst exhibits not only higher current density and stability but also higher tolerance to crossover chemicals than the commercial Pt/C catalyst. More importantly, the synthetic method is simple and inexpensive. Using photocatalysts and solar energy is another potential alternative solution for energy demand. We have synthesized a new biomimetic heterogeneous photocatalyst through the incorporation of homogeneous complex 1 [(i-SCH 2)2NC(O)C5H4N]-Fe2(CO) 6] into the highly robust zirconium-porphyrin based metal-organic framework (ZrPF). As photosensitizer ZrPF absorbs the visible light and produces photoexcited electrons that can be transferred through axial covalent bond to di-nuclear complex 1 for hydrogen generation. Additionally, we have studied the photoreduction of CO2 to CH4 using self-doped TiO2 (Ti+3@TiO 2) as photocatalytic materials. The incorporation of Ti3+ into TiO2 structures narrows the band gap, leading to significantly increased photocatalytic activity for the reduction of CO2 into renewable hydrocarbon fuel in the presence of water vapor under visible light. Finally, we demonstrate that open-framework chalcogenides can also be used as efficient photocatalysts for the reduction of CO2 to CH 4. These materials contain covalent superlattices of nanosized supertetrahedral clusters, which can be made with different metal cations to provide high electrical conductivity and current density as well as materials with different band gaps. The ability in incorporating different metal cations further enhances the material's photocatalytic activity, which could possibly provide alternative technologies for reducing CO2 in the atmosphere and simultaneously producing fuel.

  2. Institute for Functional Imaging of Materials

    E-print Network

    Weston, Ken

    imaging with theory via big data and data analytics Our scientific paradigm is shifting from the classical probing · Big data and predictive theories: biggest computation effort Now is the time to bridge physical Sci. Rep. 2013 #12;Big data: Atomic-Scale Structure and Functionality Phase 1 Phase 2 Identify Atoms

  3. New materials and functionality in spintronics devices

    NASA Astrophysics Data System (ADS)

    Shah, Lubna R.

    The next generation of electronics devices, known as spintronics, which incorporate the spin property of the carriers in combination with their charge degree of freedom is the focus of to-date research. Therefore, exciting new classes of materials have been emerging for the last few years for the development of spintronics devices. This study has been carried out to understand/control various properties of such materials at the fundamental level which is important for the spintronics devices applications. Materials studied here include magnetic semiconductors, magnetostrictive alloys and magnetic tunnel junctions (MTJ) based sensors. In the first part, a comparative study of the room temperature ferromagnetism of Co doped ZnO and CeO2 is presented with emphasis on the role of dopant, defects and host oxide. Systemic structural, magnetic, and transport analyses reveal that the nature of donor defects and host oxide plays a vital role in establishing ferromagnetism. This study provides an insight into the underlying mechanisms responsible for the ferromagnetism in Co-ZnO and Co-CeO 2. Moreover, the discussed exchange mechanisms are in good agreement with the electronic structure calculation of magnetic impurity ions and defects. Composite materials with strong magneto-electric (ME) coupling require magnetic thin films with large saturation magnetostriction constant at low magnetic fields. In the second part of this dissertation, we have studied FeGa alloys where changes in their microstructure with the incorporation of boron occur. These changes make this material a soft magnetic alloy (coercivity ˜ 2 Oe) which has a narrow ferromagnetic resonance (FMR) line width, large magnetostriction and high saturation magnetization. The anisotropy values have been extracted from study of the angular dependence of FMR. This work highlights the role of crystalline anisotropy and induced uniaxial anisotropy which determine the magnetic softness and enhanced magnetostriction at small magnetic fields. In addition, the effects of rapid thermal annealing on the structure and magnetic properties of the crystalline as well as amorphous FeGaB thin films have been studied. Additionally, new electrode materials within the magnetic tunneling junction (MTJ) have been developed using FeGaB which serve as the sensing magnetic layer. This provides a method to measure mechanical strain or stress with high sensitivity. It has been shown that TMR of greater than 12% at room temperature could be achieved in CoFeB/MgO/FeGaB based junctions. This suggests that FeGaB could be a new magnetic electrode for MTJs based pressure devices. The ability of magnetoresistive (MR) material to sense very weak magnetic fields at room temperature can be used for the magnetic sensor's design. In the third part, the Al2O3 based sensors have been studied where the shape anisotropy in the free magnetic electrode has been observed to results in a linear and hysteresis free magnetoresistance (MR) curve. Moreover, Al2O3 based sensor have 28 - 30% TMR and sensitivity up to 0.4 %/Oe over a magnetic field range of -40 Oe to 40 Oe whereas the MgO-based sensor with superparamagnetic free layer has about 90 % TMR and sensitivity of 1.1 %/Oe over the same field range.

  4. Functional Materials for Microsystems: Smart Self-Assembled Photochromic Films: Final Report

    SciTech Connect

    BURNS, ALAN R.; SASAKI, DARRYL Y.; CARPICK, R.W.; SHELNUTT, JOHN A.; BRINKER, C. JEFFREY

    2001-11-01

    This project set out to scientifically-tailor ''smart'' interfacial films and 3-D composite nanostructures to exhibit photochromic responses to specific, highly-localized chemical and/or mechanical stimuli, and to integrate them into optical microsystems. The project involved the design of functionalized chromophoric self-assembled materials that possessed intense and environmentally-sensitive optical properties (absorbance, fluorescence) enabling their use as detectors of specific stimuli and transducers when interfaced with optical probes. The conjugated polymer polydiacetylene (PDA) proved to be the most promising material in many respects, although it had some drawbacks concerning reversibility. Throughout his work we used multi-task scanning probes (AFM, NSOM), offering simultaneous optical and interfacial force capabilities, to actuate and characterize the PDA with localized and specific interactions for detailed characterization of physical mechanisms and parameters. In addition to forming high quality mono-, bi-, and tri-layers of PDA via Langmuir-Blodgett deposition, we were successful in using the diacetylene monomer precursor as a surfactant that directed the self-assembly of an ordered, mesostructured inorganic host matrix. Remarkably, the diacetylene was polymerized in the matrix, thus providing a PDA-silica composite. The inorganic matrix serves as a perm-selective barrier to chemical and biological agents and provides structural support for improved material durability in microsystems. Our original goal was to use the composite films as a direct interface with microscale devices as optical elements (e.g., intracavity mirrors, diffraction gratings), taking advantage of the very high sensitivity of device performance to real-time dielectric changes in the films. However, our optical physics colleagues (M. Crawford and S. Kemme) were unsuccessful in these efforts, mainly due to the poor optical quality of the composite films.

  5. A possibility as a new type of thermoelectric application on organic-inorganic hybrid perovsike ABI3 system: A density functional theory study

    NASA Astrophysics Data System (ADS)

    Lee, Changhoon; Hong, Jisook; Shim, Ji Hoon; Whangbo, Myung-Hwan; Postech Team

    2015-03-01

    The electronic structures of organic-inorganic hybrid systems ABI3 (A = CH3NH3, NH2CHNH2; B = Sn, Pb; X = I) in the distorted phase from their patent cubic phase are systematically studied using the first-principles calculations. Here, we examine thermoelectric properties for ABI3 compounds based on the DFT electronic structures of their optimized crystal structures. The ABI3 compounds should be considered for good thermoelectric application. We reveal that good thermoelectric performance of ABI3 systems originate from large seebeck coefficients and low thermal conductivities. As a consequence, we predict that ABI3 system is a promising material for new thermoelectric application compared to thermoelectric properties of well-known thermoelectric material Bi2Te3. This research was supported by Basic Science Research Program through the National Research Foundation of Korea(NRF) funded by the Ministry of Education (2013R1A1A2060341).

  6. Method of making nanopatterns and nanostructures and nanopatterned functional oxide materials

    DOEpatents

    Dravid, Vinayak P; Donthu, Suresh K; Pan, Zixiao

    2014-02-11

    Method for nanopatterning of inorganic materials, such as ceramic (e.g. metal oxide) materials, and organic materials, such as polymer materials, on a variety of substrates to form nanopatterns and/or nanostructures with control of dimensions and location, all without the need for etching the materials and without the need for re-alignment between multiple patterning steps in forming nanostructures, such as heterostructures comprising multiple materials. The method involves patterning a resist-coated substrate using electron beam lithography, removing a portion of the resist to provide a patterned resist-coated substrate, and spin coating the patterned resist-coated substrate with a liquid precursor, such as a sol precursor, of the inorganic or organic material. The remaining resist is removed and the spin coated substrate is heated at an elevated temperature to crystallize the deposited precursor material.

  7. Fatigue Crack Growth Analysis Models for Functionally Graded Materials

    SciTech Connect

    Dag, Serkan; Yildirim, Bora; Sabuncuoglu, Baris

    2008-02-15

    The objective of this study is to develop crack growth analysis methods for functionally graded materials (FGMs) subjected to mode I cyclic loading. The study presents finite elements based computational procedures for both two and three dimensional problems to examine fatigue crack growth in functionally graded materials. Developed methods allow the computation of crack length and generation of crack front profile for a graded medium subjected to fluctuating stresses. The results presented for an elliptical crack embedded in a functionally graded medium, illustrate the competing effects of ellipse aspect ratio and material property gradation on the fatigue crack growth behavior.

  8. [Functionalization of screen printed electrodes with organic-inorganic hybrid nano-composites for bio-sensing applications].

    PubMed

    Shumyantseva, V V; Bulko, T V; Kuzikov, A V; Khan, R; Archakov, A I

    2015-01-01

    New types of organic-inorganic hybrid nanocomposites based on nanosized Titanium (IV) oxide TiO2 (<100 nm particle size) and carbon nanotubes (CNT, outer diameter 10-15 nm, inner diamentre 2-6 nm, length 0.1-10 µm) and phosphatidilcholine were elaborated for improvement of analytical characteristics of screen printed electrodes. These nanomaterials were employed as an interface for the immobilization of skeletal myoglobin. Electrochemical behavior of myoglobin on such interfaces was characterized with cyclic voltammetry (CV) and square wave voltammetry (SWV). Direct unmediated electron transfer between myoglobin and electrodes modified with organic-inorganic hybrid nanocomposites was registered. TiO2 film and CNT film are biocompartible nanomaterials for myoglobin as was demonstrated with UV-Vis spectra. The midpoint potential of Fe3+/Fe2+ pair of myoglobin corresponded to ?1/2=-0,263 V for CNT film, and ?1/2=-0,468 V for TiO2 nanocomposite (vs. Ag/AgCl reference electrode). PMID:26350738

  9. Harvesting Vibrational Energy Using Material Work Functions

    PubMed Central

    Varpula, Aapo; Laakso, Sampo J.; Havia, Tahvo; Kyynäräinen, Jukka; Prunnila, Mika

    2014-01-01

    Vibration energy harvesters scavenge energy from mechanical vibrations to energise low power electronic devices. In this work, we report on vibration energy harvesting scheme based on the charging phenomenon occurring naturally between two bodies with different work functions. Such work function energy harvester (WFEH) is similar to electrostatic energy harvester with the fundamental distinction that neither external power supplies nor electrets are needed. A theoretical model and description of different operation modes of WFEHs are presented. The WFEH concept is tested with macroscopic experiments, which agree well with the model. The feasibility of miniaturizing WFEHs is shown by simulating a realistic MEMS device. The WFEH can be operated as a charge pump that pushes charge and energy into an energy storage element. We show that such an operation mode is highly desirable for applications and that it can be realised with either a charge shuttle or with switches. The WFEH is shown to give equal or better output power in comparison to traditional electrostatic harvesters. Our findings indicate that WFEH has great potential in energy harvesting applications. PMID:25348004

  10. A review of piezoelectric polymers as functional materials for electromechanical transducers

    NASA Astrophysics Data System (ADS)

    Ramadan, Khaled S.; Sameoto, D.; Evoy, S.

    2014-03-01

    Polymer based MEMS and microfluidic devices have the advantages of mechanical flexibility, lower fabrication cost and faster processing over silicon based ones. Also, many polymer materials are considered biocompatible and can be used in biological applications. A valuable class of polymers for microfabricated devices is piezoelectric functional polymers. In addition to the normal advantages of polymers, piezoelectric polymers can be directly used as an active material in different transduction applications. This paper gives an overview of piezoelectric polymers based on their operating principle. This includes three main categories: bulk piezoelectric polymers, piezocomposites and voided charged polymers. State-of-the-art piezopolymers of each category are presented with a focus on fabrication techniques and material properties. A comparison between the different piezoelectric polymers and common inorganic piezoelectric materials (PZT, ZnO, AlN and PMN-PT) is also provided in terms of piezoelectric properties. The use of piezopolymers in different electromechanical devices is also presented. This includes tactile sensors, energy harvesters, acoustic transducers and inertial sensors.

  11. Material selection for Multi-Function Waste Tank Facility tanks

    SciTech Connect

    Larrick, A.P.; Blackburn, L.D.; Brehm, W.F.; Carlos, W.C.; Hauptmann, J.P.; Danielson, M.J.; Westerman, R.E.; Divine, J.R.; Foster, G.M.

    1995-03-01

    This paper briefly summarizes the history of the materials selection for the US Department of Energy`s high-level waste carbon steel storage tanks. It also provides an evaluation of the materials for the construction of new tanks at the evaluation of the materials for the construction of new tanks at the Multi-Function Waste Tank Facility. The evaluation included a materials matrix that summarized the critical design, fabrication, construction, and corrosion resistance requirements: assessed. each requirement: and cataloged the advantages and disadvantages of each material. This evaluation is based on the mission of the Multi-Function Waste Tank Facility. On the basis of the compositions of the wastes stored in Hanford waste tanks, it is recommended that tanks for the Multi-Function Waste Tank Facility be constructed of ASME SA 515, Grade 70, carbon steel.

  12. High-throughput data mined prediction of inorganic compounds and computational discovery of new lithium-ion battery cathode materials

    E-print Network

    Hautier, Geoffroy (Geoffroy T. F.)

    2011-01-01

    The ability to computationally predict the properties of new materials, even prior to their synthesis, has been made possible due to the current accuracy of modern ab initio techniques. In some cases, high-throughput ...

  13. A parametric study of thermomechanical behavior of functionally gradient materials 

    E-print Network

    Chin, Che-Doong

    1996-01-01

    The dynamic thermoelastic response of functionally gradient cylinders and plates is studied. Thermomechanical coupling is significant in these materials when they are used in high temperature applications, and hence, the coupling is included...

  14. Comparison of inorganic ion exchange materials for removing cesium, strontium, and transuranic elements from K-basin water

    SciTech Connect

    Brown, G.N.; Bontha, J.R.; Carson, K.J.; Elovich, R.J.; DesChane, J.R.

    1997-10-01

    The work presented in this report was conducted by the Pacific Northwest National Laboratory (PNNL) under the Efficient Separations and Crosscutting Program (ESP), Office of Science and Technology, U.S. Department of Energy (DOE). The objective of this work was to investigate radionuclide uptake by several newly produced ion exchange materials under actual waste conditions, and to compare the performance of those materials with that of commercially available ion exchangers. The equilibrium uptake data presented in this report are useful for identifying potential materials that are capable of removing cesium and strontium from 105-KE Basin water. The data show the relative selectivities of the ion exchange materials under similar operating conditions. Additional flow studies are needed to predict material capacities and to develop complete ion exchange process flow sheets. The materials investigated in this study include commercially available ion exchangers such as IONSIV{reg_sign} IE-911 (manufactured by UOP), clinoptilolite (a naturally occurring zeolite), and materials produced on an experimental basis by AlliedSignal (biotites and nonatitanates), 3M (hexacyanoferrates), Selion Technologies, Inc. (hexacyanoferrates and titanates), and Texas A&M University (pharmacosiderites, biotites, and nonatitanates). In all, the performance of 14 ion exchange materials was evaluated at two solution-to-exchanger mass ratios (i.e., 10{sup 4} and 10{sup 5}) using actual 105-KE Basin water. Evaluation consisted of determining cesium and strontium batch distribution coefficients, loading, and decontamination factors. Actual 105-KE Basin water was obtained from a sample collected during the sludge dissolution work conducted by PNNL in FY 1996. This sample was taken from the bottom of the basin and contained significantly higher concentrations of the radioactive constituents than do samples taken from the top of the basin.

  15. Kesterite Cu2ZnSnS4 as a Low-Cost Inorganic Hole-Transporting Material for High-Efficiency Perovskite Solar Cells.

    PubMed

    Wu, Qiliang; Xue, Cong; Li, Yi; Zhou, Pengcheng; Liu, Weifeng; Zhu, Jun; Dai, Songyuan; Zhu, Changfei; Yang, Shangfeng

    2015-12-30

    Kesterite-structured quaternary semiconductor Cu2ZnSnS4 (CZTS) has been commonly used as light absorber in thin film solar cells on the basis of its optimal bandgap of 1.5 eV, high absorption coefficient, and earth-abundant elemental constituents. Herein we applied CZTS nanoparticles as a novel inorganic hole transporting material (HTM) for organo-lead halide perovskite solar cells (PSCs) for the first time, achieving a power conversion efficiency (PCE) of 12.75%, which is the highest PCE for PSCs with Cu-based inorganic HTMs reported up to now, and quite comparable to that obtained for PSCs based on commonly used organic HTM such as 2,2',7,7'-tetrakis(N,N-di-p-methoxyphenylamine)-9,9'-spirobifluorene (spiro-MeOTAD). The size of CZTS nanoparticles and its incorporation condition as HTM were optimized, and the effects of CZTS HTM on the optical absorption, crystallinity, morphology of the perovskite film and the interface between the perovskite layer and the Au electrode were investigated and compared with the case of spiro-MeOTAD HTM, revealing the role of CZTS in efficient hole transporting from the perovskite layer to the top Au electrode as confirmed by the prohibited charge recombination at the perovskite/Au electrode interface. On the basis of the effectiveness of CZTS as a low-cost HTM competitive to spiro-MeOTAD in PSCs, we demonstrate the new role of CZTS in photovoltaics as a hole conductor beyond the traditional light absorber. PMID:26646015

  16. Science Update: Inorganic Chemistry.

    ERIC Educational Resources Information Center

    Rawls, Rebecca

    1981-01-01

    Describes areas of inorganic chemistry which have changed dramatically in the past year or two, including photochemistry, electrochemistry, organometallic complexes, inorganic reaction theory, and solid state chemistry. (DS)

  17. EDITORIAL: The 2nd International Symposium on Functional Materials

    NASA Astrophysics Data System (ADS)

    Lu, L.; Lai, M. O.

    2007-12-01

    Following the success of the 1st International Symposium on Functional Materials held in Kuala Lumpur, Malaysia, 5-8 December 2005, the second symposium was held in the beautiful city of Hangzhou, People's Republic of China, 16-19 May 2007. The latter symposium was a gathering of about 200 renowned researchers from 16 countries around the world. The conference consisted of 24 symposia, 5 keynote papers, 21 invited papers, 108 oral presentations and about 160 poster papers covering the frontier areas of materials science and technology of functional materials. They included topics such as energy storage materials, ferroelectric materials, ferromagnetic materials, ferroelectric thin films, applications of functional materials, nanofabrication, computational design, shape memory alloys, application of shape memory materials, ferroelectrics and thermoelectrics, advances in characterizations, magneto-optical materials, Zn and Ti oxides, synthesis of nanopowders and wires, and many other advanced functional materials. With the receipt of more than 396 abstracts, this conference was a gathering of great minds in one place to discuss the research frontiers and discoveries in functional materials. The Organizing Committee would like to express its sincere thanks to the members of the International Advisory Committee for their invaluable contributions to the symposium. The committee is also grateful for the generous support from the many sponsors. A word of sincere thanks needs to go to Professor Roger Wäppling, Editor-in-Chief and the editorial staff of IOP Publishing for the publication of selected papers in this special issue of Physica Scripta. Finally, our deepest gratitude should be directed to the National University of Singapore, Zhejiang University and the General Research Institute for Nonferrous Metals, People's Republic of China for, without their support, the conference would not have been a success.

  18. http://lewisgroup.seas harvard.edu Printing Functional Materials

    E-print Network

    The Science of Digital Fabrication ­ 3.7.13 Polymerinks! ! #12;Several advances needed for 3D printing of high (2010); Advanced Engineering Materials (2011) Printed origami ­ simple route to complex 3D forms #12http://lewisgroup.seas harvard.edu Printing Functional Materials Jennifer A. Lewis School

  19. Production of modern functional materials based on renewable vegetable resources

    NASA Astrophysics Data System (ADS)

    Onishchenko, D. V.; Reva, V. P.

    2013-05-01

    An energy-saving technology for production of variously structured carbon modifications from a renewable vegetable raw material, i.e., the waste of agricultural crops and peat moss, has been developed. Promising functional materials — refractory compounds (tungsten and titanium carbides) and oil sorbents possessing a combination of high operating characteristics — have been formed on the basis of the synthesized carbon modifications.

  20. Organic-Inorganic Hybrid Materials Based on Basket-like {Ca?P6Mo18O73} Cages.

    PubMed

    Zhang, He; Yu, Kai; Lv, Jing-hua; Gong, Li-hong; Wang, Chun-mei; Wang, Chun-xiao; Sun, Di; Zhou, Bai-Bin

    2015-07-20

    Four basket-like organic-inorganic hybrids, formulated as [{Cu(II)(H2O)2}{Ca4(H2O)4(HO0.5)3(en)2}{Ca?P6Mo4(V)Mo14(VI)O73}]·7H2O (1), (H4bth)[{Fe(II)(H2O)}{Ca?P6Mo18(VI)O73}]·4H2O (2), (H2bih)3[{Cu(II)(H2O)2}{Ca?P6Mo2(V)Mo16(VI)O73}]·2H2O (3), (H2bib)3[{Fe(II)(H2O)2}{Ca?P6Mo2(V) Mo16(VI)O73}]·4H2O (4), (bth = 1,6-bis(triazole)hexane; bih = 1,6-bis(imidazol)hexane; bib = 1,4-bis(imidazole)butane) have been hydrothermally synthesized and fully characterized. Compounds 1-4 contain polyoxoanion [Ca?P6Mon(V)Mo18-n(VI)O73]((6+n)-) (n = 0, 2, or 4) (abbreviated as {P6Mo18O73}) as a basic building block, which is composed of a "basket body" {P2Mo14} unit and a "handle"-liked {P4Mo4} fragment encasing an alkaline-earth metal Ca(2+) cation in the cage. Compound 1 exhibits an infrequent 2D layer structure linked by the Cu(H2O)2 linker and an uncommon tetranuclear calcium complex, while compound 2 is 8-connected 2-D layers connected by binuclear {Fe2(H2O)3} segaments, which are observed for the first time as 2-D basket-like assemblies. Compounds 3 and 4 are similar 1D Z-typed chains bonded by M(H2O)2 units (M = Cu for 3 and Fe for 4). The optical band gaps of 1-4 reveal their semiconductive natures. They exhibit universal highly efficient degradation ability for typical dyes such as methylene blue, methyl orange, and rhodamine B under UV light. The lifetime and catalysis mechanism of the catalysts have been investigated. The compounds also show good bifunctional electrocatalytic behavior for oxidation of amino acids and reduction of NO2(-). PMID:26130499

  1. The features of self-assembling organic bilayers important to the formation of anisotropic inorganic materials in microgravity conditions

    NASA Technical Reports Server (NTRS)

    Talham, Daniel R.; Adair, James H.

    2005-01-01

    Materials with directional properties are opening new horizons in a variety of applications including chemistry, electronics, and optics. Structural, optical, and electrical properties can be greatly augmented by the fabrication of composite materials with anisotropic microstructures or with anisotropic particles uniformly dispersed in an isotropic matrix. Examples include structural composites, magnetic and optical recording media, photographic film, certain metal and ceramic alloys, and display technologies including flat panel displays. The new applications and the need for model particles in scientific investigations are rapidly out-distancing the ability to synthesize anisotropic particles with specific chemistries and narrowly distributed physical characteristics (e.g. size distribution, shape, and aspect ratio).

  2. Macroscopic analysis of axisymmetric functionally gradient material under thermal loading

    SciTech Connect

    Kwon, P.; Dharan, C.K.H.; Ferrari, M. )

    1994-06-01

    The axisymmetric functionally gradient materials (FGMs) subject to nonuniform temperature variations were studied with the combined use of homogenization and inhomogeneous eigenstrained media analysis. The material properties and the temperature variations were assumed to depend on the radial coordinate only. The inhomogeneous material properties of the FGM cylinder can be obtained by modulating the concentration level of spherical alumina particles in an aluminum matrix. The resulting stresses due to the temperature variation are presented for numerous distribution functions of alumina particles. It is shown that the particle distribution extensively influences the intensity and profile of the thermal stresses.

  3. Catalytic Modification of Polymers: Hydrogenation Routes to Amine Functional Materials

    E-print Network

    Catalytic Modification of Polymers: Hydrogenation Routes to Amine Functional Materials Amine Polymers Introduction Amine functional polymers and the copolymers have been widely used in application and the synthesis route needs several steps. We have studied an approach to synthesize homo and copolymers

  4. Organometallic exposure dependence on organic–inorganic hybrid material formation in polyethylene terephthalate and polyamide 6 polymer fibers

    SciTech Connect

    Akyildiz, Halil I.; Jur, Jesse S.

    2015-03-15

    The effect of exposure conditions and surface area on hybrid material formation during sequential vapor infiltrations of trimethylaluminum (TMA) into polyamide 6 (PA6) and polyethylene terephthalate (PET) fibers is investigated. Mass gain of the fabric samples after infiltration was examined to elucidate the reaction extent with increasing number of sequential TMA single exposures, defined as the times for a TMA dose and a hold period. An interdependent relationship between dosing time and holding time on the hybrid material formation is observed for TMA exposure PET, exhibited as a linear trend between the mass gain and total exposure (dose time × hold time × number of sequential exposures). Deviation from this linear relationship is only observed under very long dose or hold times. In comparison, amount of hybrid material formed during sequential exposures to PA6 fibers is found to be highly dependent on amount of TMA dosed. Increasing the surface area of the fiber by altering its cross-sectional dimension is shown to have little on the reaction behavior but does allow for improved diffusion of the TMA into the fiber. This work allows for the projection of exposure parameters necessary for future high-throughput hybrid modifications to polymer materials.

  5. Inorganic raw materials economy and provenance of chipped industry in some stone age sites of northern and central Italy.

    PubMed

    Bietti, Amilcare; Boschian, Giovanni; Crisci, Gino Mirocle; Danese, Ermanno; De Francesco, Anna Maria; Dini, Mario; Fontana, Federica; Giampietri, Alessandra; Grifoni, Renata; Guerreschi, Antonio; Liagre, Jérémie; Negrino, Fabio; Radi, Giovanna; Tozzi, Carlo; Tykot, Robert

    2004-06-01

    An opportunistic and local choice of raw materials is typically attested in the Lower and Middle Paleolithic industries throughout Italy. The quality of the raw material usually affected the flaking technology and quality of the products. In the Upper Paleolithic and the Mesolithic, raw material procurement strategies were more complex. Flint was exploited both locally, in areas where abundant outcrops of raw materials were available (such as the Lessini mountains), and in distant localities, after which it was transported or exchanged over medium/long distances. Different routes of exchange were thus followed in the various periods; good reconstruction of these routes have been provided by a study of the Garfagnana sites in Northern Tuscany, and the Mesolithic deposit of Mondeval de Sora (Dolomites). An interesting example of a Late Upper Paleolithic flint quarry and workshop were found in Abruzzo, in the San Bartolomeo shelter. The extended trade of obsidian from Lipari, Palmarola and Sardinia to the Italian Peninsula is attested in the Neolithic, with some differences concerning the age and different areas. PMID:15636064

  6. Sol-Gel Synthesis of a Biotemplated Inorganic Photocatalyst: A Simple Experiment for Introducing Undergraduate Students to Materials Chemistry

    ERIC Educational Resources Information Center

    Boffa, Vittorio; Yue, Yuanzheng; He, Wen

    2012-01-01

    As part of a laboratory course, undergraduate students were asked to use baker's yeast cells as biotemplate in preparing TiO[subscript 2] powders and to test the photocatalytic activity of the resulting materials. This laboratory experience, selected because of the important environmental implications of soft chemistry and photocatalysis, provides…

  7. Higher-Order Theory for Functionally Graded Materials

    NASA Technical Reports Server (NTRS)

    Aboudi, J.; Pindera, M. J.; Arnold, Steven M.

    2001-01-01

    Functionally graded materials (FGM's) are a new generation of engineered materials wherein the microstructural details are spatially varied through nonuniform distribution of the reinforcement phase(s). Engineers accomplish this by using reinforcements with different properties, sizes, and shapes, as well as by interchanging the roles of the reinforcement and matrix phases in a continuous manner (ref. 1). The result is a microstructure that produces continuously or discretely changing thermal and mechanical properties at the macroscopic or continuum scale. This new concept of engineering the material's microstructure marks the beginning of a revolution both in the materials science and mechanics of materials areas since it allows one, for the first time, to fully integrate the material and structural considerations into the final design of structural components. Functionally graded materials are ideal candidates for applications involving severe thermal gradients, ranging from thermal structures in advanced aircraft and aerospace engines to computer circuit boards. Owing to the many variables that control the design of functionally graded microstructures, full exploitation of the FGM's potential requires the development of appropriate modeling strategies for their response to combined thermomechanical loads. Previously, most computational strategies for the response of FGM's did not explicitly couple the material's heterogeneous microstructure with the structural global analysis. Rather, local effective or macroscopic properties at a given point within the FGM were first obtained through homogenization based on a chosen micromechanics scheme and then subsequently used in a global thermomechanical analysis.

  8. Development and investigation of functional hierarchical hybrid materials

    NASA Astrophysics Data System (ADS)

    Athauda, Thushara J.

    In this dissertation, a series of hierarchical hybrid materials were developed and their process-morphology-activity relationship was studied. In this context, zinc oxide was used as a model metal-oxide semiconductor for the development of branched hierarchical nanostructures on various flexible substrates including cotton, nylon, and electrospun organic and inorganic nanofibers. In all cases, well-defined, radially oriented, highly dense, uniform, and single crystalline arrays of ZnO nanostructures were successfully grown using an optimized hydrothermal growth strategy. This process involves seed solution treatment of a substrate with ZnO nanocrystals that will form nucleation sites for subsequent anisotropic growth of single crystalline ZnO nanowires by incubation in the growth solution. All ZnO nanowires exhibit wurtzite crystal structure oriented along the c-axis which was confirmed by XRD analysis. Seed-to-growth solution concentration ratio ([S]/[G]) was determined to be the most important process parameter on the morphology of the resulting nanostructures when applied to cotton and nylon surfaces. Increase in the [S]/[G] values resulted in the amount of ZnO grown on the surfaces to drop significantly, which also resulted in a morphological transform from nanorods to needle-like structures. Consequently, a strong dependency of the physical, optical, and electrochemical properties of the resulting materials was observed. In addition, room temperature photoluminescence measurements revealed that the band-gap of ZnO widened as the morphology changed from nanorods to nanoneedles. Additional analyses revealed that cotton bearing ZnO nanorods exhibits a lower propensity for contact transfer of E. coli than unmodified cotton fabric. Moreover, studies with nonwoven nanofibers generated by electrospinning revealed that the morphology of the branched nanostructures was also controlled by the density of the underlying fibrous platform. The amount of ZnO nanorods grown over electrospun nanofibers was higher than that of cotton and nylon fabrics, due to the increased surface area-to-volume ratio. Organic and inorganic based electrospun nanofibers such as cellulose acetate, amide, and TiO 2 have been employed as the primary platform upon which the secondary nanostructures were grown. ZnO nanowires grown on electrospun fibers were found to be highly effective photocatalysts, as indicated by the almost complete removal of the model compound methylene blue in 30 min. With the ZnO nanorods-electrospun TiO2 hierarchical systems, more effective charge transfer capacity was achieved due to enhanced state of heterojunctions and directionality of the charge carriers.

  9. Damage to inorganic materials illuminated by focused beam of x-ray free-electron laser radiation

    NASA Astrophysics Data System (ADS)

    Koyama, Takahisa; Yumoto, Hirokatsu; Tono, Kensuke; Togashi, Tadashi; Inubushi, Yuichi; Katayama, Tetsuo; Kim, Jangwoo; Matsuyama, Satoshi; Yabashi, Makina; Yamauchi, Kazuto; Ohashi, Haruhiko

    2015-05-01

    X-ray free-electron lasers (XFELs) that utilize intense and ultra-short pulse X-rays may damage optical elements. We investigated the damage fluence thresholds of optical materials by using an XFEL focusing beam that had a power density sufficient to induce ablation phenomena. The 1 ?m focusing beams with 5.5 keV and/or 10 keV photon energies were produced at the XFEL facility SACLA (SPring-8 Angstrom Compact free electron LAser). Test samples were irradiated with the focusing beams under normal and/or grazing incidence conditions. The samples were uncoated Si, synthetic silica glass (SiO2), and metal (Rh, Pt)-coated substrates, which are often used as X-ray mirror materials.

  10. Effect of the condensation of hybrid organic-inorganic sol-gel materials on the optical properties of tripan blue

    NASA Astrophysics Data System (ADS)

    Hicks, Craig; Morshed, Muhammad; Melia, Garrett; Barton, Killian; Duffy, Brendan; Oubaha, Mohamed

    2015-09-01

    The work reported in this paper highlights the effect of sol-gel structures on the optical properties of a typical organic dye (Trypan Blue, TB). Three transition-metal-based hybrid sol-gel materials with different structures and morphologies were developed and characterised by TEM. The optical properties of TB were investigated by incorporating it in the different sol-gel materials and the UV-Visible spectra recorded in both liquid and solid state, in thin-coatings cured at temperatures in the range 100-150 °C. These studies revealed two relevant results. First, the sol-gel morphology plays a critical role in the optical properties of the dye. The effect of the sol-gel host matrix on the optical properties of the dye is attributed to the steric hindrance of the nanostructures, themselves intimately dependant on the reactivity of the transition metal. For instance, the less condensed system showed the highest reactivity with the dye, while the more condensed system exhibited limited interaction with the dye, symbolised by a significant change or quasi-unchanged UV-Visible spectra, respectively. It is also shown that the increase of the condensation degree of the sol-gel coatings by heat-curing can dramatically alter the optical properties of the dye especially for the most condensed sol-gel systems. This has been attributed to proximity effects enabled by the further increase of the materials densities. The results reported here aim to provide a better understanding of how material formulations can influence the optical properties of organic dyes and suggest that the structure of the host matrix along with the applied curing process have to be fully considered and assessed in the choice of organic dyes for a given application.

  11. Some functional properties of composite material based on scrap tires

    NASA Astrophysics Data System (ADS)

    Plesuma, Renate; Malers, Laimonis

    2013-09-01

    The utilization of scrap tires still obtains a remarkable importance from the aspect of unloading the environment from non-degradable waste [1]. One of the most prospective ways for scrap tires reuse is a production of composite materials [2] This research must be considered as a continuation of previous investigations [3, 4]. It is devoted to the clarification of some functional properties, which are considered important for the view of practical applications, of the composite material. Some functional properties of the material were investigated, for instance, the compressive stress at different extent of deformation of sample (till 67% of initial thickness) (LVS EN 826) [5] and the resistance to UV radiation (modified method based on LVS EN 14836) [6]. Experiments were realized on the purposefully selected samples. The results were evaluated in the correlation with potential changes of Shore C hardness (Shore scale, ISO 7619-1, ISO 868) [7, 8]. The results showed noticeable resistance of the composite material against the mechanical influence and ultraviolet (UV) radiation. The correlation with the composition of the material, activity of binder, definite technological parameters, and the conditions supported during the production, were determined. It was estimated that selected properties and characteristics of the material are strongly dependent from the composition and technological parameters used in production of the composite material, and from the size of rubber crumb. Obtained results show possibility to attain desirable changes in the composite material properties by changing both the composition and technological parameters of examined material.

  12. PREFACE: International Conference on Functional Materials and Nanotechnologies (FM&NT2012)

    NASA Astrophysics Data System (ADS)

    Sternberg, Andris; Muzikante, Inta; Sarakovskis, Anatolijs; Grinberga, Liga

    2012-08-01

    The International Conference Functional Materials and Nanotechnologies (FM&NT - 2012) was held in Riga, 17-20 April 2012 at the Institute of Solid State Physics, University of Latvia (ISSP UL). The conference was organised by ISSP UL in co-operation with National Research programme in Materials Science and Information Technologies of Latvia. The purpose of this series of conferences is to bring together scientists, researchers, engineers and students from universities, research institutes and related industrial companies working in the field of advanced material science, energy and materials technologies. The contributions of the participants were grouped according to three main topics of the conference: 1. Multifunctional Materials including advanced inorganic, organic and hybrid materials; ferroics; multiscale and multiphenomenal material modeling and simulation 2. Nanotechnologies including progressive methods, technologies and design for investigation of nanoparticles, nanostructures, nanocomposites, thin films and coatings; 3. Energy including perspective materials and technologies for renewable and hydrogen energy, fuel cells, photovoltaics and developing diverse energy systems. A special section devoted to Organic Materials was organized to commemorate a long-time organizer of the FM&NT conference series, Dr. habil. phys, academician Inta Muzikante who passed away on 15 February 2012. The number of registered participants from 21 countries was nearly 300. During the three days of the conference 2 plenary, 16 invited, 54 oral reports and 184 posters were presented. 64 papers, based on these reports, are included in this volume of IOP Conference Series: Materials Science and Engineering. Additional information about FM&NT-2012 is available at its homepage http://www.fmnt.lu.lv. The Organizing Committee would like to thank all the speakers, contributors, session chairs, referees and other involved staff for their efforts in making the FM&NT-2012 successful. The Organizing Committee sincerely hopes that the Conference gave all the participants new insights into the widespread development of functional materials and nanotechnologies and would enhance the circulation of the information released at the meeting. Inta Muzikante Andris Sternberg Liga Grinberga Anatolijs Sarakovskis Conference photograph The manuscripts are published thanks to the financial support from ERAF project 'Atbalsts starptautiskas sadarbibas projektiem zinatne un tehnologijas LU Cietvielu fizikas instituta' Nr.2010/0204/2DP/2.1.1.2.0./10/APIA/VIAA/010 Sponsors Sponsors flag Sponsors logo International Organizing Committee 1. Andris Sternberg (chairperson), Institute of Solid State Physics, University of Latvia, Latvia 2. Juras Banys, Vilnius University, Lithuania 3. Gunnar Borstel, University of Osnabrück, Germany 4. Niels E Christensen, University of Aarhus, Denmark 5. Robert A Evarestov, St. Petersburg State University, Russia 6. Claes-Goran Granqvist, Uppsala University, Sweden 7. Dag Høvik, The Research Council of Norway, Norway 8. Marco Kirm, Institute of Physics, University of Tartu, Estonia 9. Jiri Kulda, Institut Laue-Langevin, France 10. Witold Lojkowski, Institute of High Pressure Physics, Poland 11. Ergo Nommiste, University of Tartu, Estonia 12. Ingólfur Torbjörnsson, Icelandic Centre for Research, Iceland 13. Marcel H. Van de Voorde, University of Technology Delft, The Netherlands International Program Committee 1. Liga Grinberga (chairperson), Institute of Solid State Physics, University of Latvia, Latvia 2. Eugene Kotomin, Max Planck Institute for Solid State Research, Germany 3. Martins Rutkis, Institute of Solid State Physics, University of Latvia, Latvia 4. Inta Muzikante, Institute of Solid State Physics, University of Latvia, Latvia 5. Liga Berzina-Cimdina, Institute of Biomaterials and Biomechanics, Riga Technical University, Latvia 6. Janis Grabis, Institute of Inorganic Chemistry, Riga Technical University, Latvia 7. Linards Skuja, Institute of Solid State Physics, University of Latvia, Latvia 8. Maris Spr

  13. Functionalized Materials From Elastomers to High Performance Thermoplastics

    SciTech Connect

    Laura Ann Salazar

    2003-05-31

    Synthesis and incorporation of functionalized materials continues to generate significant research interest in academia and in industry. If chosen correctly, a functional group when incorporated into a polymer can deliver enhanced properties, such as adhesion, water solubility, thermal stability, etc. The utility of these new materials has been demonstrated in drug-delivery systems, coatings, membranes and compatibilizers. Two approaches exist to functionalize a material. The desired moiety can be added to the monomer either before or after polymerization. The polymers used range from low glass transition temperature elastomers to high glass transition temperature, high performance materials. One industrial example of the first approach is the synthesis of Teflon(reg. sign). Poly(tetrafluoroethylene) (PTFE or Teflon(reg. sign)) is synthesized from tetrafluoroethylene, a functionalized monomer. The resulting material has significant property differences from the parent, poly(ethylene). Due to the fluorine in the polymer, PTFE has excellent solvent and heat resistance, a low surface energy and a low coefficient of friction. This allows the material to be used in high temperature applications where the surface needs to be nonabrasive and nonstick. This material has a wide spread use in the cooking industry because it allows for ease of cooking and cleaning as a nonstick coating on cookware. One of the best examples of the second approach, functionalization after polymerization, is the vulcanization process used to make tires. Natural rubber (from the Hevea brasiliensis) has a very low glass transition temperature, is very tacky and would not be useful to make tires without synthetic alteration. Goodyear's invention was the vulcanization of polyisoprene by crosslinking the material with sulfur to create a rubber that was tough enough to withstand the elements of weather and road conditions. Due to the development of polymerization techniques to make cis-polyisoprene, natural rubber is no longer needed for the manufacturing of tires, but vulcanization is still utilized.

  14. Weathering processes and the composition of inorganic material transported through the orinoco river system, Venezuela and Colombia

    USGS Publications Warehouse

    Stallard, R.F.; Koehnken, L.; Johnsson, M.J.

    1991-01-01

    The composition of river-borne material in the Orinoco River system is related primarily to erosion regime, which in turn is related to tectonic setting; especially notable is the contrast between material derived from tectonically active mountain belts and that from stable cratonic regions. For a particular morpho-tectonic region, the compositional suites of suspended sediment, bed material, overback deposits, and dissolved phases are fairly uniform are are typically distinct from whose of other regions. For each region, a consistent set of chemical weathering reactions can be formulated to explain the composition of dissolved and solid loads. In developing these formulations, erosion on slopes and storage of solids in soils and alluvial sediments are important considerations. Compositionally verymature sediment is derived from areas of thick soils where erosion is transport limited and from areas where sediments are stored for extended periods of time in alluvial deposits. Compositionally immature sediments are derived from tectonically active mountain belts where erosion is weathering limited. Weathering-limited erosion also is important in the elevated parts of the Guayana Shield within areas of sleep topography. Compared to the mountain belts, sediments derived from elevated parts of the Shield are more mature. A greater degree of chemical weathering seems to be needed to erode the rock types typical of the Shield. The major-element chemistry and mineral composition of sediment delivered by the Orinoco River to the ocean are controlled by rivers that have their headwaters in mountain belts and cross the Llanos, a region of alluvial plains within the foreland basin. The composition of sediments in rivers that drain the Shield seems to be established primarily at the site of soil formation, whereas for rivers that drain the mountain belts, additional weathering occurs during s episodes of storage on alluvial plains as sediments are transported across the Llanos to the main stem of the Orinoco. After mixing into the main stem, there seems to be little subsequent alteration of sediment. ?? 1991.

  15. The role of physical and chemical properties of Pd nanostructured materials immobilized on inorganic carriers on ion formation in atmospheric pressure laser desorption/ionization mass spectrometry.

    PubMed

    Silina, Yuliya E; Koch, Marcus; Volmer, Dietrich A

    2014-06-01

    Fundamental parameters influencing the ion-producing efficiency of palladium nanostructures (nanoparticles [Pd-NP], nanoflowers, nanofilms) during laser irradiation were studied in this paper. The nanostructures were immobilized on the surface of different solid inorganic carrier materials (porous and mono-crystalline silicon, anodic porous aluminum oxide, glass and polished steel) by using classical galvanic deposition, electroless local deposition and sputtering. It was the goal of this study to investigate the influence of both the nanoparticular layer as well as the carrier material on ion production for selected analyte molecules. Our experiments demonstrated that the dimensions of the synthesized nanostructures, the thickness of the active layers, surface disorders, thermal conductivity and physically or chemically adsorbed water influenced signal intensities of analyte ions during surface-assisted laser desorption/ionization (SALDI) while no effects such as plasmon resonance, photoelectric effect or catalytic activity were expected to occur. Excellent LDI abilities were seen for Pd-NPs immobilized on steel, while Pd nanoflowers on porous silicon exhibited several disadvantages; viz, strong memory effects, dependency of the analytical signal on amount of physically and chemically adsorbed water inside porous carrier, reduced SALDI activity from unstable connections between Pd and semiconductor material, decrease of the melting point of pure silicon after Pd immobilization and resulting strong laser ablation of metal/semiconductor complex, as well as significantly changed surface morphology after laser irradiation. The analytical performance of Pd-NP/steel was further improved by applying a hydrophobic coating to the steel surface before galvanic deposition. This procedure increased the distance between Pd-NPs, thus reducing thermal stress upon LDI; it simultaneously decreased spot sizes of deposited sample solutions. PMID:24913399

  16. Evaluation of naturally occurring radioactive materials (NORMs) in inorganic and organic oilfield scales from the Middle East.

    PubMed

    Bassioni, Ghada; Abdulla, Fareed; Morsy, Zeinab; El-Faramawy, Nabil

    2012-04-01

    The distribution of natural nuclide gamma-ray activities and their respective annual effective dose rates, produced by potassium-40 (??K), uranium-238 (²³?U), thorium-232 (²³²Th), and radium-226 (²²?Ra), were determined for 14 oilfield scale samples from the Middle East. Accumulated radioactive materials concentrate in tubing and surface equipment, and workers at equipment-cleaning facilities and naturally occurring radioactive materials (NORMs) disposal facilities are the population most at risk for exposure to NORM radiation. Gamma-spectra analysis indicated that photo-gamma lines represent the parents of 10 radioactive nuclides: ²³?Th, plutonium-239, actinium-228, ²²?Ra, lead-212 (²¹²Pb), ²¹?Pb, thallium-238 (²??Tl), bismuth-212 (²¹²Bi), ²¹?Bi, and ??K. These nuclides represent the daughters of the natural radioactive series ²³?U and ²³²Th with ??K as well. The mean activity concentration of ²³?U, ²³²Th, and ??K were found to be 25.8 ± 11.6, 18.3 ± 8.1, and 4487.2 ± 2.5% Bq kg?¹ (average values for 14 samples), respectively. The annual effective dose rates and the absorbed doses in air, both indoor and outdoor, for the samples were obtained as well. The results can be used to assess the respective hazard on workers in the field and represent a basis for revisiting current engineering practices. PMID:21892762

  17. Novel Functionalized Ceramic Getter Materials for Adsorption of Radioiodine

    SciTech Connect

    Mattigod, Shas V.; Fryxell, Glen E.; Parker, Kent E.; Kaplan, Daniel I.

    2003-08-02

    A new class of getter materials has been synthesized for immobilization of long-lived radionuclides such as 129I. These novel materials consist of nanoporous ceramic substrates with tailored pore sizes ranging from 2 – 20 nm. These high surface area (~1000 m2/g) ceramic substrates have been functionalized with self-assembled monolayers consisting of soft cation-capped thiol-functionality. The resulting getter materials exhibit highly dense binding sites, and excellent selectivity for iodide. The effectiveness of these novel getter materials was evaluated using radioiodide-spiked samples of surface water and concrete leachate and adsorption performance was compared with natural sulfide mineral getter materials. The data indicated that the novel getter materials have very high affinity for radioiodide (Kd: 4 x 104 – 3 x 105 ml/g and 6 x 105 ml/g in surface and concrete leachate respectively). Comparatively, the radioiodide Kd values for natural mineral getters were typically two to three orders magnitude less than the novel getters. The results indicated that the synthetic getter materials have the potential to immobilize and therefore retard the migration of 129I in the subsurface environment. Additional studies are being conducted to evaluate the long-term stability of these materials in waste disposal environments.

  18. Ionic self-assembly for functional hierarchical nanostructured materials.

    PubMed

    Faul, Charl F J

    2014-12-16

    CONSPECTUS: The challenge of constructing soft functional materials over multiple length scales can be addressed by a number of different routes based on the principles of self-assembly, with the judicious use of various noncovalent interactions providing the tools to control such self-assembly processes. It is within the context of this challenge that we have extensively explored the use of an important approach for materials construction over the past decade: exploiting electrostatic interactions in our ionic self-assembly (ISA) method. In this approach, cooperative assembly of carefully chosen charged surfactants and oppositely charged building blocks (or tectons) provides a facile noncovalent route for the rational design and production of functional nanostructured materials. Generally, our research efforts have developed with an initial focus on establishing rules for the construction of novel noncovalent liquid-crystalline (LC) materials. We found that the use of double-tailed surfactant species (especially branched double-tailed surfactants) led to the facile formation of thermotropic (and, in certain cases, lyotropic) phases, as demonstrated by extensive temperature-dependent X-ray and light microscopy investigations. From this core area of activity, research expanded to cover issues beyond simple construction of anisotropic materials, turning to the challenge of inclusion and exploitation of switchable functionality. The use of photoactive azobenzene-containing ISA materials afforded opportunities to exploit both photo-orientation and surface relief grating formation. The preparation of these anisotropic LC materials was of interest, as the aim was the facile production of disposable and low-cost optical components for display applications and data storage. However, the prohibitive cost of the photo-orientation processes hampered further exploitation of these materials. We also expanded our activities to explore ISA of biologically relevant tectons, specifically deoxyguanosine monophosphate. This approach proved, in combination with block copolymer (BCP) self-assembly, very fruitful for the construction of complex and hierarchical functional materials across multiple length scales. Molecular frustration and incommensurability, which played a major role in structure formation in combination with nucleotide assembly, have now become important tools to tune supramolecular structure formation. These concepts, that is, the use of BCP assembly and incommensurability, in combination with metal-containing polymeric materials, have provided access to novel supramolecular morphologies and, more importantly, design rules to prepare such constructs. These design rules are now also being applied to the assembly of electroactive oligo(aniline)-based materials for the preparation of highly ordered functional soft materials, and present an opportunity for materials development for applications in energy storage. In this Account, we therefore discuss investigations into (i) the inclusion and preparation of supramolecular photoactive and electroactive materials; (ii) the exploitation and control over multiple noncovalent interactions to fine-tune function, internal structure, and long-range order and (iii) exploration of construction over multiple length scales by combination of ISA with well-known BCP self-assembly. Combination of ISA with tuning of volume fractions, mutual compatibility, and molecular frustration now provides a versatile tool kit to construct complex and hierarchical functional materials in a facile noncovalent way. A direct challenge for future ISA activities would certainly be the construction of functional mesoscale objects. However, within a broader scientific context, the challenge would be to exploit this powerful assembly tool for application in areas of research with societal impact, for example, energy storage and generation. The hope is that this Account will provide a platform for such future research activities and opportunities. PMID:25191750

  19. Analytical Model for Thermal Elastoplastic Stresses of Functionally Graded Materials

    SciTech Connect

    Zhai, P. C.; Chen, G.; Liu, L. S.; Fang, C.; Zhang, Q. J.

    2008-02-15

    A modification analytical model is presented for the thermal elastoplastic stresses of functionally graded materials subjected to thermal loading. The presented model follows the analytical scheme presented by Y. L. Shen and S. Suresh [6]. In the present model, the functionally graded materials are considered as multilayered materials. Each layer consists of metal and ceramic with different volume fraction. The ceramic layer and the FGM interlayers are considered as elastic brittle materials. The metal layer is considered as elastic-perfectly plastic ductile materials. Closed-form solutions for different characteristic temperature for thermal loading are presented as a function of the structure geometries and the thermomechanical properties of the materials. A main advance of the present model is that the possibility of the initial and spread of plasticity from the two sides of the ductile layers taken into account. Comparing the analytical results with the results from the finite element analysis, the thermal stresses and deformation from the present model are in good agreement with the numerical ones.

  20. Functionalized apertures for the detection of chemical and biological materials

    DOEpatents

    Letant, Sonia E. (Livermore, CA); van Buuren, Anthony W. (Livermore, CA); Terminello, Louis J. (Danville, CA); Thelen, Michael P. (Danville, CA); Hope-Weeks, Louisa J. (Brentwood, CA); Hart, Bradley R. (Brentwood, CA)

    2010-12-14

    Disclosed are nanometer to micron scale functionalized apertures constructed on a substrate made of glass, carbon, semiconductors or polymeric materials that allow for the real time detection of biological materials or chemical moieties. Many apertures can exist on one substrate allowing for the simultaneous detection of numerous chemical and biological molecules. One embodiment features a macrocyclic ring attached to cross-linkers, wherein the macrocyclic ring has a biological or chemical probe extending through the aperture. Another embodiment achieves functionalization by attaching chemical or biological anchors directly to the walls of the apertures via cross-linkers.

  1. PREFACE: 4th International Symposium on Functional Materials (ISFM2011)

    NASA Astrophysics Data System (ADS)

    Yin, Shu; Sekino, Tohru; Tanaka, Shun-ichiro; Sato, Tsugio; Lu, Li; Xue, Dongfeng

    2012-01-01

    The 4th International Symposium on Functional Materials (ISFM2011) was held in Sendai, Japan, on 2-6 August 2011. This Special Issue of Journal of Physics: Conference Series (JPCS) consists of partial manuscripts which were presented at ISFM2011. Advanced materials have experienced a dramatic increase in demand for research, development and applications. The aim of the International Symposium on Functional Materials (ISFM) was to provide an overview of the present status with historical background and to foresee future trends in the field of functional materials. The 4th symposium, ISFM 2011, covered a wide variety of topics within state-of-the-art advanced materials science and technology, and focused especially on four major categories including: Environmental Materials, Electronic Materials, Energy Materials and Biomedical Materials. As you know, a massive earthquake and the Tsunami that followed occurred near the Tohoku region on 11 March 2011. After the earthquake, although there were many difficulties in continuing to organize the symposium, we received warm encouragement from many researchers and societies, especially from the members of the International Advisory Committee and Organizing Committee, so that ISFM2011 could be held on schedule. We are honored that ISFM2011 was the first formal international academic conference held in the Tohoku area of Japan after the 11 March earthquake. About 140 participants from 14 countries took part in the ISFM2011 symposium, which included five plenary talks by world-leading scientists, 32 invited talks, and many oral and poster presentations. We are delighted to see that many researchers are interested in the synthesis and the properties as well as the applications of functional materials. Many fruitful and exciting research achievements were presented in the symposium. We believe that this symposium provided a good chance for scientists to communicate and exchange opinions with each other. We would also like to express our sincere appreciation to all the members of the International Advisory Committee, the Organizing Committee, and all the authors and participants. It is expected that the published output of this special issue will be accepted as an original and valuable contribution to the literature in the functional materials field. Guest Editors Dr Shu Yin Tohoku University, Japan Dr Tohru Sekino Tohoku University, Japan Professor Shun-ichiro Tanaka, IMRAM, Tohoku University, Japan Professor Tsugio Sato IMRAM, Tohoku University, Japan Professor Li Lu National University of Singapore, Singapore Professor Dongfeng Xue Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, China Conference photograph Group photograph of the participants of ISFM2011 held in Sendai, 4 August 2011

  2. Multi-phase functionally graded materials for thermal barrier systems

    SciTech Connect

    Jackson, M.R.; Ritter, A.M.; Gigliotti, M.F.; Kaya, A.C.; Gallo, J.P.

    1996-12-31

    Jet engine and gas turbine hot section components can be protected from the 1,350--1,650 C combustion gases by thermal barrier coatings (TBCs). Metallic candidates for functionally graded material (FGM) coatings have been evaluated for potential use in bonding zirconia to a single crystal superalloy. Properties for four materials were studied for the low-expansion layer adjacent to the ceramic. Ingots were produced for these materials, and oxidation, expansion and modulus were determined. A finite element model was used to study effects of varying the FGM layers. Elastic modulus dominated stress generation, and a 20--25% reduction in thermal stress generated within the zirconia layer may be possible.

  3. Non-formaldehyde, crease resistant agent for cotton fabrics based on an organic-inorganic hybrid material.

    PubMed

    Schramm, Christian; Rinderer, Beate; Tessadri, Richard

    2014-05-25

    1,2,3,4-Butanetetracarboxylic acid (BTCA) was reacted with (3-aminopropyl)triethoxysilane (APTES) to a poly(amic)acid (PAA). The molar ratios of BTCA and APTES were 1/1 (B/A-1/1), 1/2 (B/A-1/2), 1/3 (B/A-1/3), and 1/4 (B/A-1/4). The as-prepared precursor solution was applied to cotton substrates. After thermal treatment (180°C) the physical-mechanical properties of the cotton samples were tested by means of dry crease recovery angle and tensile strength. For B/A-1/1 treated fabrics a significant improvement of the crease resistance was observed. FT-IR spectra revealed the formation of an imide group and an ester linkage, indicating the cross-linking of the cellulosic material. SEM images showed a smooth surface. As evidenced by TGA data the thermal stability of the cotton samples was not increased. No hydrophobicity could be observed. For B/A-1/3 and (B/A-1/4) modified cotton samples no crease resistant properties were detected. However, enhanced contact angle values were measured. A reaction mechanism for the formation of the ladder-like polysilsesquioxane and the cross-linking reaction is proposed. PMID:24708956

  4. Inorganic Fullerenes, Onions, and Tubes

    ERIC Educational Resources Information Center

    York, Andrew P. E.

    2004-01-01

    Buckminsterfullerene, which is in the shape of a soccer-ball was first discovered in 1985, has many applications as a good lubricant, or as a new superconductor. The synthesis of these inorganic fullerenes involves a great deal of interdisciplinary research between physicists, material scientists, engineers and chemists from various fields.

  5. Inorganic Reaction Mechanisms. Part I

    ERIC Educational Resources Information Center

    Cooke, D. O.

    1976-01-01

    Provides a collection of data on the mechanistic aspects of inorganic chemical reactions. Wherever possible includes procedures for classroom demonstration or student project work. The material covered includes gas phase reactions, reactions in solution, mechanisms of electron transfer, the reaction between iron III and iodine, and hydrolysis. (GS)

  6. Aeroelastic Tailoring of a Plate Wing with Functionally Graded Materials

    NASA Technical Reports Server (NTRS)

    Dunning, Peter D.; Stanford, Bret K.; Kim, H. Alicia; Jutte, Christine V.

    2014-01-01

    This work explores the use of functionally graded materials for the aeroelastic tailoring of a metallic cantilevered plate-like wing. Pareto trade-off curves between dynamic stability (flutter) and static aeroelastic stresses are obtained for a variety of grading strategies. A key comparison is between the effectiveness of material grading, geometric grading (i.e., plate thickness variations), and using both simultaneously. The introduction of material grading does, in some cases, improve the aeroelastic performance. This improvement, and the physical mechanism upon which it is based, depends on numerous factors: the two sets of metallic material parameters used for grading, the sweep of the plate, the aspect ratio of the plate, and whether the material is graded continuously or discretely.

  7. Graphene and carbon nanodots in mesoporous materials: an interactive platform for functional applications

    NASA Astrophysics Data System (ADS)

    Innocenzi, Plinio; Malfatti, Luca; Carboni, Davide

    2015-07-01

    The present review is focused on a specific class of nanocomposites obtained through integration of graphene or carbon-based nanomaterials (such as carbon nanodots) with mesoporous inorganic or hybrid materials, obtained via template assisted self-assembly. The task of integrating graphene and carbon nanodots with a self-assembly process is still very challenging and this review shows some of the solutions which have been envisaged so far. These nanocomposite materials are an ideal interactive platform for developing innovative functional applications; they have a high capability of undergoing integration into advanced devices, which well exploits the advantage of tuning the wide properties and flexibility of the soft-chemistry route. A wide range of applications have been developed so far which span from sensing to electronics up to optics and biomedicine. Even though a large number of proof-of-concepts have been reported to date, an even greater expansion of applications in the field is expected to happen in the near future.

  8. Pseudodielectric Functions of Uniaxial Materials in Certain Symmetry Directions

    SciTech Connect

    Jellison Jr, Gerald Earle; Baba, Justin S

    2006-01-01

    The pseudodielectric function is often used to represent ellipsometric data and corresponds to the actual dielectric functions of materials when there is no surface overlayer and the material is isotropic. If a uniaxial material is oriented such that the optic axis is in the plane of incidence or is perpendicular to the plane of incidence, then the cross-polarization terms are zero and appropriate pseudodielectric functions can be determined from the ellipsometry data. We calculate the pseudodielectric functions for uniaxial crystals in three primary symmetry directions: (1) the optic axis is perpendicular to the plane of incidence, (2) the optic axis is in the plane of the sample surface and parallel to the plane of incidence, and (3) the optic axis is in the plane of the sample surface and perpendicular to the plane of incidence. These results are expanded in terms of the difference in the ordinary and extraordinary dielectric functions and compared with the approximation ofAspnes [J. Opt. Soc. Am.70, 1275 (1980)]. Comparisons are made with experimental results on oriented crystals of rutile (TiO2), and a simple procedure is presented to determine the complex dielectric function from standard ellipsometry techniques.

  9. Structure and function analysis of Escherichia coli inorganic pyrophosphatase: is a hydroxide ion the key to catalysis?

    PubMed

    Salminen, T; Käpylä, J; Heikinheimo, P; Kankare, J; Goldman, A; Heinonen, J; Baykov, A A; Cooperman, B S; Lahti, R

    1995-01-24

    Using site-directed mutagenesis, we have completed replacing all 17 putative active site residues of Escherichia coli inorganic pyrophosphatase (PPase). We report here the production of 11 new variant proteins and their initial characterization, including thermostability, hydrophobicity, oligomeric structure, and specific activity at pH 8. Studies of the pH-rate profiles of 12 variants containing substitutions for potentially essential residues showed that the effect of the mutation was always to increase the pKa of a basic group essential for both substrate binding and catalysis by 1-3 pH units. The D70E variant had the lowest activity at all pHs; the K29R, R43K, and K142R variants also had low kcat/Km values. The principal effect seen in the other variant proteins was higher and sharper pH optima; their pH-independent kcat and kcat/Km values changed at most by a factor of 8. Our results suggest that the most likely candidate for the essential basic group affected by all mutations in the active site is a hydroxide ion stabilized by coordination to the essential Mg2+ ions. Analyzing our results using the structure recently obtained for E. coli PPase [Kankare et al. (1994) Protein Eng. 7, 823-830] led us to identify a group of residues, centered around Asp70 and including Tyr55, Asp65, Asp67, Asp102, and Lys104, that we believe binds the magnesium ions that are critical for the activity, possibly by stabilizing the essential hydroxide. Others, including Lys29, Arg43, and Lys142, are more spread out and more positively charged. They appear to be involved in binding substrate and product. Tyr55 is also a key part of the hydrophobic core of E. coli PPase; when it or residues that interact with it are conservatively mutated, there are changes in the overall structure of the enzyme as assayed by thermostability, hydrophobicity, or oligomeric structure. PMID:7827037

  10. Anomalous dielectric behaviour in centrosymmetric organic–inorganic hybrid chlorobismuthate(III) containing functional N,N-dimethylethylammonium ligand. Crystal structure and properties

    SciTech Connect

    Piecha, A.; G?gor, A.; W?c?awik, M.; Jakubas, R.; Medycki, W.

    2013-01-15

    Graphical abstract: Display Omitted Highlights: ? Novel organic–inorganic hybrid chlorobismuthate(III). ? Unprecedented dielectric response in non-polar material. ? Dielectric relaxation characterized by an exceptionally large dielectric increment. ? The NMR measurements confirmed dynamic disorder of cations. -- Abstract: The structure of [C{sub 2}H{sub 5}NH(CH{sub 3}){sub 2}{sup +}]{sub 3}[BiCl{sub 6}{sup ?}] (abbreviated as DCB) was determined by a single-crystal X-ray diffraction at 115 K. The compound adopts tetragonal symmetry with the space group I4{sub 1}/acd; a = 23.35 ?, c = 17.60 ?, V = 9598 ?{sup 3} and Z = 16. The crystal structure of DCB is built up of isolated [BiCl{sub 6}]{sup 3?} units and N,N-dimethylethylammonium counterions that are accommodated in the large voids. At ambient temperature two-thirds of the counterions appear to be dynamically disordered. Dynamics of this type of cations contributes to the enhanced dielectric permittivity of DCB. A low frequency dielectric relaxation process that takes place between 200 and 300 K is characterized by an exceptionally large dielectric increment, ?? > 100, which is unprecedented in nonferroelectric materials. The molecular motions of the N,N-dimethylethylammonium cations were studied by means of {sup 1}H NMR spin-lattice relaxation time measurements.

  11. A photometric function for diffuse reflection by particulate materials

    NASA Technical Reports Server (NTRS)

    Meador, W. E.; Weaver, W. R.

    1975-01-01

    A photometric function is proposed to describe the diffuse reflection of radiation by particulate materials. Both multiple scattering and the dominant effects of particle shadowing are included and the function is verified by comparisons with the photometries of laboratory surfaces. Brightness measurements of planetary and other diffusely scattering surfaces can be used to calculate the brightness for geometries other than those used in the measurements and for which the Minnaert function does not apply. The measurements also can be directly related to such surface characteristics as particle size, single-particle albedo, and compactness.

  12. ELECTROSPINNING APPLICATIONS IN MECHANOCHEMISTRY AND MULTI-FUNCTIONAL HYDROGEL MATERIALS

    E-print Network

    Braun, Paul

    ELECTROSPINNING APPLICATIONS IN MECHANOCHEMISTRY AND MULTI- FUNCTIONAL HYDROGEL MATERIALS BY AUSTIN of nonpolar spiropyran also results in the formation of a polar species. Electrospinning, a process used nanofibers. It was also determined whether the high strains during electrospinning could be used to activate

  13. Stochastic multiscale models for fracture analysis of functionally graded materials

    E-print Network

    Rahman, Sharif

    A functionally graded material (FGM) is an engineered composite medium in which the composition of constituent. An FGM derived from an optimized compositional variation and microstructure rather than traditional]. However, the extent to which an FGM can be tailored to produce target mechanical performance depends

  14. Love wave propagation in functionally graded piezoelectric material layer.

    PubMed

    Du, Jianke; Jin, Xiaoying; Wang, Ji; Xian, Kai

    2007-03-01

    An exact approach is used to investigate Love waves in functionally graded piezoelectric material (FGPM) layer bonded to a semi-infinite homogeneous solid. The piezoelectric material is polarized in z-axis direction and the material properties change gradually with the thickness of the layer. We here assume that all material properties of the piezoelectric layer have the same exponential function distribution along the x-axis direction. The analytical solutions of dispersion relations are obtained for electrically open or short circuit conditions. The effects of the gradient variation of material constants on the phase velocity, the group velocity, and the coupled electromechanical factor are discussed in detail. The displacement, electric potential, and stress distributions along thickness of the graded layer are calculated and plotted. Numerical examples indicate that appropriate gradient distributing of the material properties make Love waves to propagate along the surface of the piezoelectric layer, or a bigger electromechanical coupling factor can be obtained, which is in favor of acquiring a better performance in surface acoustic wave (SAW) devices. PMID:17107699

  15. Organic/Inorganic Composite Latexes: The Marriage of Emulsion Polymerization and Inorganic Chemistry

    NASA Astrophysics Data System (ADS)

    Bourgeat-Lami, Elodie; Lansalot, Muriel

    This review article describes recent advances in the synthesis and properties of waterborne organic/inorganic colloids elaborated through conventional emulsion polymerization, a well-established technology. These materials can be defined as aqueous suspensions of composite latex particles made up of organic and inorganic domains organized into well-defined core-shell, multinuclear, raspberry-like, multipod-like, or armored morphologies. Particular emphasis is placed on the synthetic strategies for fabrication of these colloidal materials. Two main approaches are described: the polymerization of organic monomers in the presence of preformed inorganic particles, and the reverse approach by which inorganic materials are synthesized in the presence of preformed polymer latexes. The list of examples provided in this review is by no means exhaustive but rather intends to give an overview of synthetic methods for selected inorganic compounds (e.g., silica, iron oxide, pigments, clays, quantum dots, and metals), and briefly reports on potential applications of the resulting materials.

  16. Functional and Multifunctional Polymers: Materials for Smart Structures

    NASA Technical Reports Server (NTRS)

    Arnold, S.; Pratt, L. M.; Li, J.; Wuagaman, M.; Khan, I. M.

    1996-01-01

    The ultimate goal of the research in smart structures and smart materials is the development of a new generation of products/devices which will perform better than products/devices built from passive materials. There are a few examples of multilayer polymer systems which function as smart structures, e.g. a synthetic muscle which is a multilayer assembly of a poly(ethylene) layer, a gold layer, and a poly(pyrrole) layer immersed in a liquid electrolyte. Oxidation and reductions of the active pyrrole layer causes the assembly to reversibly deflect and mimic biological muscles. The drawback of such a setup is slow response times and the use of a liquid electrolyte. We have developed multifunctional polymers which will eliminate the use of a liquid electrolyte, and also because the functionalities of the polymers are within a few hundred angstroms, an improved response time to changes in the external field should be possible. Such multifunctional polymers may be classified as the futuristic 'smart materials.' These materials are composed of a number of different functionalities which work in a synergistic fashion to function as a device. The device performs on the application of an external field and such multifunctional polymers may be scientifically labeled as 'field responsive polymers.' Our group has undertaken a systematic approach to develop functional and multifunctional polymers capable of functioning as field responsive polymers. Our approach utilizes multicomponent polymer systems (block copolymers and graft copolymers), the strategy involves the preparation of block or graft copolymers where the functionalities are limited to different phases in a microphase separated system. Depending on the weight (or volume) fractions of each of the components, different microstructures are possible. And, because of the intimate contact between the functional components, an increase in the synergism between the functionalities may be observed. In this presentation, three examples of multifunctional polymers developed in our labs will be reported. The first class of multifunctional polymers are the microphase separated mixed (ionic and electronic) conducting or MIEC block copolymers. The second class being developed in our labs are the biocompatible conductive materials and the conductive fluids. The final class may be considered microwave active smart polymers.

  17. Surface functionalization of inorganic nano-crystals with fibronectin and E-cadherin chimera synergistically accelerates trans-gene delivery into embryonic stem cells

    SciTech Connect

    Kutsuzawa, K.; Chowdhury, E.H.; Nagaoka, M.; Maruyama, K.; Akiyama, Y.; Akaike, T. . E-mail: takaike@bio.titech.ac.jp

    2006-11-24

    Stem cells holding great promises in regenerative medicine have the potential to be differentiated to a specific cell type through genetic manipulation. However, conventional ways of gene transfer to such progenitor cells suffer from a number of disadvantages particularly involving safety and efficacy issues. Here, we report on the development of a bio-functionalized inorganic nano-carrier of DNA by embedding fibronectin and E-cadherin chimera on the carrier, leading to its high affinity interactions with embryonic stem cell surface and accelerated trans-gene delivery for subsequent expression. While only apatite nano-particles were very inefficient in transfecting embryonic stem cells, fibronectin-anchored particles and to a more significant extent, fibronectin and E-cadherin-Fc-associated particles dramatically enhanced trans-gene delivery with a value notably higher than that of commercially available lipofection system. The involvement of both cell surface integrin and E-cadherin in mediating intracellular localization of the hybrid carrier was verified by blocking integrin binding site with excess free fibronectin and up-regulating both integrin and E-cadherin through PKC activation. Thus, the new establishment of a bio-functional hybrid gene-carrier would promote and facilitate development of stem cell-based therapy in regenerative medicine.

  18. Functionalized mesoporous silica materials for molsidomine adsorption: Thermodynamic study

    SciTech Connect

    Alyoshina, Nonna A.; Parfenyuk, Elena V.

    2013-09-15

    A series of unmodified and organically modified mesoporous silica materials was prepared. The unmodified mesoporous silica was synthesized via sol–gel synthesis in the presence of D-glucose as pore-forming agent. The functionalized by phenyl, aminopropyl and mercaptopropyl groups silica materials were prepared via grafting. The fabricated adsorbent materials were characterized by Fourier transform infrared spectroscopy (FTIR) analysis, N{sub 2} adsorption/desorption and elemental analysis methods. Then their adsorption properties for mesoionic dug molsidomine were investigated at 290–313 K and physiological pH value. Thermodynamic parameters of molsidomine adsorption on the synthesized materials have been calculated. The obtained results showed that the adsorption process of molsidomine on the phenyl modified silica is the most quantitatively and energetically favorable. The unmodified and mercaptopropyl modified silica materials exhibit significantly higher adsorption capacities and energies for molsidomine than the aminopropyl modified sample. The effects are discussed from the viewpoint of nature of specific interactions responsible for the adsorption. - Graphical abstract: Comparative analysis of the thermodynamic characteristics of molsidomine adsorption showed that the adsorption process on mesoporous silica materials is controlled by chemical nature of surface functional groups. Molsidomine adsorption on the phenyl modified silica is the most quantitatively and energetically favorable. Taking into account ambiguous nature of mesoionic compounds, it was found that molsidomine is rather aromatic than dipolar. Display Omitted - Highlights: • Unmodified and organically modified mesoporous silica materials were prepared. • Molsidomine adsorption on the silica materials was studied. • Phenyl modified silica shows the highest adsorption capacity and favorable energy. • Molsidomine exhibits the lowest affinity to aminopropyl modified silica.

  19. Development of pillared M(IV) phosphate phosphonate inorganic organic hybrid ion exchange materials for applications in separations found in the nuclear fuel cycle

    NASA Astrophysics Data System (ADS)

    Burns, Jonathan David

    This dissertation focuses on key intergroup and intragroup separations found in the back end of the nuclear fuel cycle, specifically americium from lanthanides and americium from other actinides, most importantly americium from curium. Our goal is to implement a liquid-solid separation process to reduce waste and risk of contamination by the development of metal(IV) phosphate phosphonate inorganic organic hybrid ion exchange materials with the ideal formula of M(O6P2C6H4)0.5 (O3POA) ·nH2O, where M = Zr or Sn, A = H or Na. These materials have previously shown to have high affinity for Ln, this work will expand on the previous studies and provide methods for the above target separation, exploiting oxidation state and ion charge to drive the separation process. The optimum hydrothermal reaction conditions were determined by adjusting parameters such as reaction temperature and time, as well as the phosphonate to phosphate (pillar-to-spacer) ligands ratio. Following these results four bulk syntheses were performed and their ion exchange properties were thoroughly examined. Techniques such as inductively coupled mass spectrometry and liquid scintillation counting were used to determine the affinity of the materials towards Na+, Cs+, Ca2+, Sr 2+, Ni2+, Nd3+, Sm3+, Ho3+, Yb3+, NpO2+, Pu4+, PuO22+, Am3+, AmO2+, and Cm3+. Separation factors in the thousands have been observed for intergroup separations of the Ln from the alkali, alkaline earth, and low valent transition metals. A new method for Am oxidation was developed, which employed Na 2S2O8 as the oxidizing agent and Ca(OCl) 2 as the stabilizing agent for AmO2+ synthesis. Separation factors of 30-60 for Nd3+ and Eu3+ from AmO2+, as well as 20 for Cm3+ from AmO2+ were observed at pH 2. The work herein shows that a liquid-solid separation can be carried out for these difficult separations by means of oxidation and ion exchange.

  20. Remote Monitoring, Inorganic Monitoring

    EPA Science Inventory

    This chapter provides an overview of applicability, amenability, and operating parameter ranges for various inorganic parameters:this chapter will also provide a compilation of existing and new online technologies for determining inorganic compounds in water samples. A wide vari...

  1. Confined-plume chemical deposition: rapid synthesis of crystalline coatings of known hard or superhard materials on inorganic or organic supports by resonant IR decomposition of molecular precursors.

    PubMed

    Ivanov, Borislav L; Wellons, Matthew S; Lukehart, Charles M

    2009-08-26

    A one-step process for preparing microcrystalline coatings of known superhard, very hard, or ultraincompressible ceramic compositions on either inorganic or organic supports is reported. Midinfrared pulsed-laser irradiation of preceramic chemical precursors layered between IR-transmissive hard/soft supports under temporal and spatial confinement at a laser wavelength resonant with a precursor vibrational band gives one-step deposition of crystalline ceramic coatings without incurring noticeable collateral thermal damage to the support material. Reaction plume formation at the precursor/laser beam interface initiates confined-plume, chemical deposition (CPCD) of crystalline ceramic product. Continuous ceramic coatings are produced by rastering the laser beam over a sample specimen. CPCD processing of the Re-B single-source precursor, (B(3)H(8))Re(CO)(4), the dual-source mixtures, Ru(3)(CO)(12)/B(10)H(14) or W(CO)(6)/B(10)H(14), and the boron/carbon single-source precursor, o-B(10)C(2)H(12), confined between Si wafer or NaCl plates gives microcrystalline deposits of ReB(2), RuB(2), WB(4), or B(4)C, respectively. CPCD processing of Kevlar fabric wetted by (B(3)H(8))Re(CO)(4) produces an oriented, microcrystalline coating of ReB(2) on the Kevlar fabric without incurring noticeable thermal damage of the polymer support. Similarly, microcrystalline coatings of ReB(2) can be formed on IR-transmissive IR2, Teflon, or Ultralene polymer films. PMID:19642682

  2. Observations and implications of liquid-liquid phase separation at high relative humidities in secondary organic material produced by ?-pinene ozonolysis without inorganic salts

    NASA Astrophysics Data System (ADS)

    Renbaum-Wolff, L.; Song, M.; Marcolli, C.; Zhang, Y.; Liu, P. F.; Grayson, J. W.; Geiger, F. M.; Martin, S. T.; Bertram, A. K.

    2015-11-01

    Particles consisting of secondary organic material (SOM) are abundant in the atmosphere. To predict the role of these particles in climate, visibility, and atmospheric chemistry, information on particle phase state (i.e. single liquid, two liquids, solid and so forth) is needed. This paper focuses on the phase state of SOM particles free of inorganic salts produced by the ozonolysis of ?-pinene. Phase transitions were investigated both in the laboratory and with a thermodynamic model over the range of < 0.5 % to 100 % relative humidity (RH) at 290 K. In the laboratory studies, a single phase was observed from 0 to 95 % RH while two liquid phases were observed above 95 % RH. For increasing RH, the mechanism of liquid-liquid phase separation (LLPS) was spinodal decomposition. The RH range at which two liquid phases were observed did not depend on the direction of RH change. In the modelling studies at low RH values, the SOM took up hardly any water and was a single organic-rich phase. At high RH values, the SOM underwent LLPS to form an organic-rich phase and an aqueous phase, consistent with the laboratory studies. The presence of LLPS at high RH-values has consequences for the cloud condensation nuclei (CCN) activity of SOM particles. In the simulated Köhler curves for SOM particles, two local maxima are observed. Depending on the composition of the SOM, the first or second maximum can determine the critical supersaturation for activation. The presence of LLPS at high RH-values can explain inconsistencies between measured CCN properties of SOM particles and hygroscopic growth measured below water saturation.

  3. Molecular Modeling of Heme Proteins Using MOE: Bio-Inorganic and Structure-Function Activity for Undergraduates

    ERIC Educational Resources Information Center

    Ray, Gigi B.; Cook, J. Whitney

    2005-01-01

    A biochemical molecular modeling project on heme proteins suitable for an introductory Biochemistry I class has been designed with a 2-fold objective: i) to reinforce the correlation between protein three-dimensional structure and function through a discovery oriented project, and ii) to introduce students to the fields of bioinorganic and…

  4. Functional soft materials from metallopolymers and metallosupramolecular polymers

    NASA Astrophysics Data System (ADS)

    Whittell, George R.; Hager, Martin D.; Schubert, Ulrich S.; Manners, Ian

    2011-03-01

    Synthetic polymers containing metal centres are emerging as an interesting and broad class of easily processable materials with properties and functions that complement those of state-of-the-art organic macromolecular materials. A diverse range of different metal centres can be harnessed to tune macromolecular properties, from transition- and main-group metals to lanthanides. Moreover, the linkages that bind the metal centres can vary almost continuously from strong, essentially covalent bonds that lead to irreversible or 'static' binding of the metal to weak and labile, non-covalent coordination interactions that allow for reversible, 'dynamic' or 'metallosupramolecular', binding. Here we review recent advances and challenges in the field and illustrate developments towards applications as emissive and photovoltaic materials; as optical limiters; in nanoelectronics, information storage, nanopatterning and sensing; as macromolecular catalysts and artificial enzymes; and as stimuli-responsive materials. We focus on materials in which the metal centres provide function; although they can also play a structural role, systems where this is solely their purpose have not been discussed.

  5. Synthesis, crystal structure, vibrational spectroscopy, optical properties and theoretical studies of a new organic-inorganic hybrid material: [((CH3)2NH2)+]6·[(BiBr6)3-]2

    NASA Astrophysics Data System (ADS)

    Ben Ahmed, A.; Feki, H.; Abid, Y.

    2014-12-01

    A new organic-inorganic hybrid material, [((CH3)2NH2)+]6·[(BiBr6)3-]2, has been synthesized and characterized by X-ray diffraction, FT-IR, Raman spectroscopy and UV-Visible absorption. The studied compound crystallizes in the triclinic system, space group P1bar with the following parameters: a=8.4749(6)(Å), b=17.1392(12)(Å), c=17.1392(12)(Å), ? = 117.339(0)°, ? = 99.487(0)°, ? = 99.487(0)° and Z = 2. The crystal lattice is composed of a two discrete (BiBr6)3- anions surrounded by six ((CH3)2NH2)+ cations. Complex hydrogen bonding interactions between (BiBr6)3- and organic cations from a three-dimensional network. Theoretical calculations were performed using density functional theory (DFT) for studying the molecular structure, vibrational spectra and optical properties of the investigated molecule in the ground state. The full geometry optimization of designed system is performed using DFT method at B3LYP/LanL2DZ level of theory using the Gaussian03. The optimized geometrical parameters obtained by DFT calculations are in good agreement with single crystal XRD data. The vibrational spectral data obtained from FT-IR and Raman spectra are assigned based on the results of the theoretical calculations. The energy and oscillator strength calculated by Time-Dependent Density Functional Theory (TD-DFT) results complements with the experimental findings. The simulated spectra satisfactorily coincide with the experimental UV-Visible spectrum. The results show good consistent with the experiment and confirm the contribution of metal orbital to the HOMO-LUMO boundary.

  6. Alkoxide routes to Inorganic Materials

    SciTech Connect

    Thomas, George H

    2007-12-01

    An all alkoxide solution chemistry utilizing metal 2-methoxyethoxide complexes in 2-methoxyethanol was used to deposit thin-films of metal oxides on single-crystal metal oxide substrates and on biaxially textured metal substrates. This same chemistry was used to synthesize complex metal oxide nanoparticles. Nuclear Magnetic Resonance spectroscopy was used to study precursor solutions of the alkaline niobates and tantalates. Film crystallization temperatures were determined from x-ray diffraction patterns of powders derived from the metal oxide precursor solutions. Film structure was determined via x-ray diffraction. Film morphology was studied using scanning electron microscopy (SEM) and atomic force microscopy (AFM). Epitaxial thin-films of strontium bismuth tantalate (SrBi{sub 2}Ta{sub 2}O{sub 9}, SBT) and strontium bismuth niobate (SrBi{sub 2}Nb{sub 2}O{sub 9}, SBN) were deposited on single crystal [1 0 0] magnesium oxide (MgO) buffered with lanthanum manganate (LaMnO{sub 3}, LMO). Epitaxial thin films of LMO were deposited on single crystal [100] MgO via Rf-magnetron sputtering and on single crysal [100] lanthanum aluminate (LaAlO{sub 3}) via the chemical solution deposition technique. Epitaxial thin-films of sodium potassium tantalate (na{sub 0.5}K{sub 0.5}TaO{sub 3}, NKT), sodium potassium niobate (Na{sub 0.5}K{sub 0.5}NbO{sub 3}, NKN) and sodium potassium tantalum niobate (Na{sub 0.5}K{sub 0.5}Ta{sub 0.5}O{sub 3}, NKTN) were deposited on single crystal [1 0 0] lanthanum aluminate and [1 0 0] MgO substrates (NKT and NKN) and biaxially textured metal substrates via the chemical solution deposition technique. Epitaxial growth of thin-films of NKT, NKN and NKTN was observed on LAO and Ni-5% W. Epitaxial growth of thin-films of NKN and the growth of c-axis aligned thin-films of NKT was observed on MgO. Nanoparticles of SBT, SBN, NKT and NKN were synthesized in reverse micelles from alkoxide precursor solutions. X-ray diffraction and transmission electron spectroscopy investigations reveal that amorphous nanoparticles ({approx} 5 nm) of SBT and SBN were synthesized. X-ray diffraction investigations reveal that nanoparticles ({approx} nm) of NKT and NKN were also synthesized by this method.

  7. Surface acoustic wave depth profiling of a functionally graded material

    SciTech Connect

    Goossens, Jozefien; Leclaire, Philippe; Xu Xiaodong; Glorieux, Christ; Martinez, Loic; Sola, Antonella; Siligardi, Cristina; Cannillo, Valeria; Van der Donck, Tom; Celis, Jean-Pierre

    2007-09-01

    The potential and limitations of Rayleigh wave spectroscopy to characterize the elastic depth profile of heterogeneous functional gradient materials are investigated by comparing simulations of the surface acoustic wave dispersion curves of different profile-spectrum pairs. This inverse problem is shown to be quite ill posed. The method is then applied to extract information on the depth structure of a glass-ceramic (alumina) functionally graded material from experimental data. The surface acoustic wave analysis suggests the presence of a uniform coating region consisting of a mixture of Al{sub 2}O{sub 3} and glass, with a sharp transition between the coating and the substrate. This is confirmed by scanning electron microscope with energy dispersive x-ray analysis.

  8. A model for designing functionally gradient material joints

    SciTech Connect

    Messler, R.W. Jr.; Jou, M.; Orling, T.T.

    1995-05-01

    An analytical, thin-plate layer model was developed to assist research and development engineers in the design of functionally gradient material (FGM) joints consisting of discrete steps between end elements of dissimilar materials. Such joints have long been produced by diffusion bonding using intermediates or multiple interlayers; welding, brazing or soldering using multiple transition pieces; and glass-to-glass or glass-to-metal bonding using multiple layers to produce matched seals. More recently, FGM joints produced by self-propagating high-temperature synthesis (SHS) are attracting the attention of researchers. The model calculates temperature distributions and associated thermally induced stresses, assuming elastic behavior, for any number of layers of any thickness or composition, accounting for critically important thermophysical properties in each layer as functions of temperature. It is useful for assuring that cured-in fabrication stresses from thermal expansion mismatches will not prevent quality joint production. The model`s utility is demonstrated with general design cases.

  9. Applications of inorganic nanoparticles as therapeutic agents

    NASA Astrophysics Data System (ADS)

    Kim, Taeho; Hyeon, Taeghwan

    2014-01-01

    During the last decade, various functional nanostructured materials with interesting optical, magnetic, mechanical and chemical properties have been extensively applied to biomedical areas including imaging, diagnosis and therapy. In therapeutics, most research has focused on the application of nanoparticles as potential delivery vehicles for drugs and genes, because nanoparticles in the size range of 2-100 nm can interact with biological systems at the molecular level, and allow targeted delivery and passage through biological barriers. Recent investigations have even revealed that several kinds of nanomaterials are intrinsically therapeutic. Not only can they passively interact with cells, but they can also actively mediate molecular processes to regulate cell functions. This can be seen in the treatment of cancer via anti-angiogenic mechanisms as well as the treatment of neurodegenerative diseases by effectively controlling oxidative stress. This review will present recent applications of inorganic nanoparticles as therapeutic agents in the treatment of disease.

  10. Transmission Electron Microscopy as a Tool to Image Bio-Inorganic Nanohybrids: The Case of Phage-Gold Nanocomposites

    PubMed Central

    Cao, Binrui; Xu, Hong; Mao, Chuanbin

    2011-01-01

    In recent years, bio-inorganic nanohybrids composed of biological macromolecules and functional inorganic nanomaterials have revealed many unique properties that show promise for the future. Transmission electron microscopy (TEM) is a popular and relatively simple tool that can offer a direct visualization of the nanomaterials with high resolutions. When TEM is applied to visualize bio-inorganic nanohybrids, a treatment of negative staining is necessary due to the presence of biological molecules in the nanohybrids except for those with densely packed inorganic materials. However, the conventional negative-staining procedure for regular biological samples cannot be directly applied to such bio-inorganic nanohybrids. To image a specific bio-inorganic nanohybrid, negative-staining factors such as negative stain type, working pH, staining time, and drying method, should be identified. Currently, no detailed studies have been done to investigate how to adjust negative-staining factors based on specific bio-inorganic nanohybrids. In this study, bacteriophage-gold nanoparticle hybrids were chosen as a model to systematically study the effects of each factor on the negative staining of the nanohybrids. The best staining conditions for gold nanoparticle-phage nanohybrids were obtained and the effects of each factor on the negative staining of general nanohybrids were discussed. This work indicates that with proper staining it is possible to use TEM to directly visualize both biological and inorganic components without introducing any artifact. PMID:21678527

  11. Supersonic flutter analysis of thin cracked functionally graded material plates

    E-print Network

    Natarajan, S; Bordas, S

    2012-01-01

    In this paper, the flutter behaviour of simply supported square functionally graded material plates immersed in a supersonic flow is studied. An enriched 4-noded quadrilateral element based on field consistency approach is used for this study and the crack is modelled independent of the underlying mesh. The material properties are assumed to be temperature dependent and graded only in the thickness direction. The effective material properties are estimated using the rule of mixtures. The formulation is based on the first order shear deformation theory and the shear correction factors are evaluated employing the energy equivalence principle. The influence of the crack length, the crack orientation, the flow angle and the gradient index on the aerodynamic pressure and the frequency are numerically studied. The results obtained here reveal that the critical frequency and the critical pressure decreases with increase in crack length and it is minimum when the crack is aligned to the flow angle.

  12. Butterfly effects: novel functional materials inspired from the wings scales.

    PubMed

    Zhang, Wang; Gu, Jiajun; Liu, Qinglei; Su, Huilan; Fan, Tongxiang; Zhang, Di

    2014-10-01

    Through millions of years of evolutionary selection, nature has created biological materials with various functional properties for survival. Many complex natural architectures, such as shells, bones, and honeycombs, have been studied and imitated in the design and fabrication of materials with enhanced hardness and stiffness. Recently, more and more researchers have started to research the wings of butterflies, mostly because of their dazzling colors. It was found that most of these iridescent colors are caused by periodic photonic structures on the scales that make up the surfaces of these wings. These materials have recently become a focus of multidiscipline research because of their promising applications in the display of structural colors, and in advanced sensors, photonic crystals, and solar cells. This paper review aims to provide a perspective overview of the research inspired by these wing structures in recent years. PMID:25087928

  13. Organic and inorganic–organic thin film structures by molecular layer deposition: A review

    PubMed Central

    Sundberg, Pia

    2014-01-01

    Summary The possibility to deposit purely organic and hybrid inorganic–organic materials in a way parallel to the state-of-the-art gas-phase deposition method of inorganic thin films, i.e., atomic layer deposition (ALD), is currently experiencing a strongly growing interest. Like ALD in case of the inorganics, the emerging molecular layer deposition (MLD) technique for organic constituents can be employed to fabricate high-quality thin films and coatings with thickness and composition control on the molecular scale, even on complex three-dimensional structures. Moreover, by combining the two techniques, ALD and MLD, fundamentally new types of inorganic–organic hybrid materials can be produced. In this review article, we first describe the basic concepts regarding the MLD and ALD/MLD processes, followed by a comprehensive review of the various precursors and precursor pairs so far employed in these processes. Finally, we discuss the first proof-of-concept experiments in which the newly developed MLD and ALD/MLD processes are exploited to fabricate novel multilayer and nanostructure architectures by combining different inorganic, organic and hybrid material layers into on-demand designed mixtures, superlattices and nanolaminates, and employing new innovative nanotemplates or post-deposition treatments to, e.g., selectively decompose parts of the structure. Such layer-engineered and/or nanostructured hybrid materials with exciting combinations of functional properties hold great promise for high-end technological applications. PMID:25161845

  14. Ceramic/polymer functionally graded material (FGM) lightweight armor system

    SciTech Connect

    Petrovic, J.J.; McClellan, K.J.

    1998-12-31

    This is the final report of a two-year, Laboratory Directed Research and Development (LDRD) project at the Los Alamos National Laboratory (LANL). Functionally graded material is an enabling technology for lightweight body armor improvements. The objective was to demonstrate the ability to produce functionally graded ceramic-polymer and ceramic-metal lightweight armor materials. This objective involved two aspects. The first and key aspect was the development of graded-porosity boron-carbide ceramic microstructures. The second aspect was the development of techniques for liquid infiltration of lightweight metals and polymers into the graded-porosity ceramic. The authors were successful in synthesizing boron-carbide ceramic microstructures with graded porosity. These graded-porosity boron-carbide hot-pressed pieces were then successfully liquid-infiltrated in vacuum with molten aluminum at 1,300 C, and with liquid polymers at room temperature. Thus, they were able to demonstrate the feasibility of producing boron carbide-aluminum and boron carbide-polymer functionally graded materials.

  15. Material-specific transfer function model and SNR in CT

    NASA Astrophysics Data System (ADS)

    Brunner, Claudia C.; Kyprianou, Iacovos S.

    2013-10-01

    This study presents an analytical model for the edge spread function (ESF) of a clinical CT system that allows reliable fits of noisy ESF data. The model was used for the calculation of the material-specific transfer function TF and an estimation of the signal transfer and the signal-to-noise ratio (SNR) in 2D. Images of the Catphan phantom were acquired with a clinical Siemens Somatom Sensation Cardiac 64 CT scanner combining four different x-ray tube outputs (40, 150, 250 and 350 mAs) with four different reconstruction filters, which covered the range from very smooth (B10s) to very sharp (B70s). The images of the high- and mid-contrast cylinders of the phantom’s ‘Geometry and Sensitometry’ module (air, Teflon, Delrin and PMP) were used to sample material-specific ESF curves. The ESF curves were fitted with the analytical model we developed based on a linear combination of Boltzmann and Gaussian functions. The analytical model of the ESF was used to obtain the Fourier-based material-specific transfer function TF, as well as the spatial-domain point spread function (PSF). TF was subsequently used to estimate the signal transfer, which was compared to the actual reconstructed image of a 3.0 mm diameter Teflon pin. The noise power spectrum (NPS) was calculated from images of a uniform water phantom under the same technique parameters. The task-specific SNR was calculated for all technique parameters from the model-based TF, the measured NPS and simulated 3 mm diameter disc signals modeling the aforementioned materials. Bootstrapping was performed to estimate the standard deviation of the TF and the SNR. The analytical model we developed accurately captured the features of the CT ESF data. The coefficient of determination R2, a metric that describes the goodness of the fit, had a median value of 0.9995, and decreased for low tube output, low contrast and the sharp reconstruction filter. Our analysis showed that ESF, PSF and TF depended not only on the reconstruction filter, but also on the tube output and the material of the cylinders. For B40s and B70s, the TF of Delrin was significantly higher than the TF of other materials in the frequency range of 0.4-0.9 mm-1. The estimated signal transfer agreed well with the actual reconstructed image of the Teflon pin. For the technique parameters we used the SNR values ranged between [64, 320], [64, 281], [37, 137] and [33, 117] for air, Teflon, Delrin and PMP respectively. While for high-contrast materials the smoothest reconstruction filter resulted in the highest SNR, for mid-contrast materials the standard filter gave the best results. The presented approach provides an accurate, analytical description of the material-specific ESF, PSF and TF as well as an estimate of the signal transfer. The transfer function TF together with the NPS and simulated signals allow the calculation of a task-specific SNR.

  16. Nearly Perfect Triplet-Triplet Energy Transfer from Wannier Excitons to Naphthalene in Organic-Inorganic Hybrid Quantum-Well Materials

    NASA Astrophysics Data System (ADS)

    Ema, K.; Inomata, M.; Kato, Y.; Kunugita, H.; Era, M.

    2008-06-01

    We report the observation of extremely efficient energy transfer (greater than 99%) in an organic-inorganic hybrid quantum-well structure consisting of perovskite-type lead bromide well layers and naphthalene-linked ammonium barrier layers. Time-resolved photoluminescence measurements confirm that the transfer is triplet-triplet Dexter-type energy transfer from Wannier excitons in the inorganic well to the triplet state of naphthalene molecules in the organic barrier. Using measurements in the 10 300 K temperature range, we also investigated the temperature dependence of the energy transfer.

  17. Synthesis of functionalized mesoporous material with various organo-silanes.

    PubMed

    Bae, Jung A; Hwang, Seong Hee; Song, Ki-Chang; Jeon, Jong-Ki; Ko, Young Soo; Yim, Jin-Heong

    2010-01-01

    Two kinds of ordered mesoporous silicas, SBA-15 and MSU-H, have been synthesized and functionalized by direct and post synthesis method to widen their various application possibilities. In this study, phenyltrimethoxysilane (PTMS), methacryloxy-methyltrimethoxysilane (MAMTMS), 2-(3,4-epoxycyclohexyl)ethyltrimethoxysilane (ECETMS), and N(beta-aminoethyl)-gamma-aminopropylmethyldimethoxysilane (AEAPMDMS) were used as a silane precursor for the functionalization. The post synthesis was more effective method to sustain ordered pore structure than the direct synthesis method under our experimental conditions. The surface area and pore size of mesoporous silica SBA-15 and MSU-H decreased through the functionalization process. FT-IR and XPS results confirmed the functionalized silane existence in the SBA-15/MAMTMS. These functional groups (vinyl, epoxide, and amine group) could be useful for various applications such as a linker of functional organic materials or active metal for heterogeneous catalysts. As a practical instance, rhodium immobilized on the aminated SBA-15 was investigated as a 1-octene hydroformylation. PMID:20352849

  18. The ``Missing Compounds'' affair in functionality-driven material discovery

    NASA Astrophysics Data System (ADS)

    Zunger, Alex

    2014-03-01

    In the paradigm of ``data-driven discovery,'' underlying one of the leading streams of the Material Genome Initiative (MGI), one attempts to compute high-throughput style as many of the properties of as many of the N (about 10**5- 10**6) compounds listed in databases of previously known compounds. One then inspects the ensuing Big Data, searching for useful trends. The alternative and complimentary paradigm of ``functionality-directed search and optimization'' used here, searches instead for the n much smaller than N configurations and compositions that have the desired value of the target functionality. Examples include the use of genetic and other search methods that optimize the structure or identity of atoms on lattice sites, using atomistic electronic structure (such as first-principles) approaches in search of a given electronic property. This addresses a few of the bottlenecks that have faced the alternative, data-driven/high throughput/Big Data philosophy: (i) When the configuration space is theoretically of infinite size, building a complete data base as in data-driven discovery is impossible, yet searching for the optimum functionality, is still a well-posed problem. (ii) The configuration space that we explore might include artificially grown, kinetically stabilized systems (such as 2D layer stacks; superlattices; colloidal nanostructures; Fullerenes) that are not listed in compound databases (used by data-driven approaches), (iii) a large fraction of chemically plausible compounds have not been experimentally synthesized, so in the data-driven approach these are often skipped. In our approach we search explicitly for such ``Missing Compounds''. It is likely that many interesting material properties will be found in cases (i)-(iii) that elude high throughput searches based on databases encapsulating existing knowledge. I will illustrate (a) Functionality-driven discovery of topological insulators and valley-split quantum-computer semiconductors, as well as (b) Use of ``first principles thermodynamics'' to discern which of the previously ``missing compounds'' should, in fact exist and in which structure. Synthesis efforts by Poeppelmeier group at NU realized 20 never-before-made half-Heusler compounds out of the 20 predicted ones, in our predicted space groups. This type of theory-led experimental search of designed materials with target functionalities may shorten the current process of discovery of interesting functional materials. Supported by DOE ,Office of Science, Energy Frontier Research Center for Inverse Design

  19. Preparation, characterization and properties of amino-functionalized montmorillonite and composite layer-by-layer assembly with inorganic nanosheets

    NASA Astrophysics Data System (ADS)

    Huang, Guo-bo; Ge, Chang-hua; He, Bing-jing

    2011-06-01

    An amino-functionalized montmorillonite (APTMS-MMT) was prepared by the grafting of 3-aminopropyltrimethoxysilane (APTMS) on the surface of MMT via the ultrasonic synthesis process and characterized by a variety of techniques: FT-IR, thermogravimetic analysis (TGA), particles size analysis and ?-potential measurement. The results showed the size and size distribution of APTMS-MMT particles were decreased, and the ?-potential of particles was increased obviously via the ultrasonic synthesis process. The particles of 30% APTMS-MMT US (MMT modified with 30 wt% APTMS with ultrasonic synthesis process) had a z-average diameter of about 500 nm and a polydispersity index of 0.2. The resultant 30% APTMS-MMT US was dispersed uniformly and stably in water. The poly(acrylic acid) (PAA)/APTMS-MMT multilayer films were grown through layer-by-layer (LBL) deposition of PAA and APTMS-MMT. SEM results indicated that the ultrasonic synthesis of APTMS-MMT increased dispersability of clay sheets at high loadings. The thermal stability and mechanical properties of PAA/APTMS-MMT composites were investigated by TGA and tensile test respectively. The results showed the ultrasonic synthesis of APTMS-MMT enhanced the thermal stability and mechanical properties of PAA/APTMS-MMT composites significantly. PAA/30% APTMS-MMT US composite displayed 3 times higher strength and 6 times higher Young's modulus when compared with pure PAA polymer.

  20. Magnesium and inorganic phosphate content in CSF related to blood-brain barrier function in neurological disease.

    PubMed

    Heipertz, R; Eickhoff, K; Karstens, K H

    1979-02-01

    In normal controls and in a large number of neurological patients divided into certain disease groups both Mg and PO4 were determined in cerebrospinal fluid (CSF) and serum. For both Mg and PO4 there was a marked concentration gradient between CSF and serum in normals where Mg was higher and PO4 content lower in CSF. Comparison of CSF values with serum values of patients showed pathological changes only in CSF, serum values always being within the control range. A number of disease processes associated with a disturbance of blood-brain barrier (BBB) function such as inflammatory CNS disease or CNS tumors showed significant alterations of PO4 concentrations in CSF which are interpreted as an approximation of serum values. A similar decrease of Mg did not reach statistical significance. Both Mg and PO4 in CSF showed a correlation with CSF protein concentrations, but no relationship with cells in CSF. Patients with cerebrosvascular disease were not significantly different from controls as regards their Mg and PO4 in CSF, but a small subgroup consisting of patients with an intracranial hemorrhage showed elevation of both Mg and PO4 which could signify cell necrosis rather than BBB dysfunction. Patients with disc protrusion or peripheral neuropathy did not demonstrate any abnormality of CSF Mg and PO4. In the multiple sclerosis group individual patients had elevated CSF concentrations of PO4 but the group as a whole is not different from the controls. PMID:430103

  1. Apparatus for depositing a low work function material

    DOEpatents

    Balooch, Mehdi; Dinh, Long N.; Siekhaus, Wigbert J.

    2006-10-10

    Short-wavelength photons are used to ablate material from a low work function target onto a suitable substrate. The short-wavelength photons are at or below visible wavelength. The elemental composition of the deposit is controlled by the composition of the target and the gaseous environment in which the ablation process is performed. The process is carried out in a deposition chamber to which a short-wavelength laser is mounted and which includes a substrate holder which can be rotated, tilted, heated, or cooled. The target material is mounted onto a holder that spins the target during laser ablation. In addition, the deposition chamber is provided with a vacuum pump, an external gas supply with atomizer and radical generator, a gas generator for producing a flow of molecules on the substrate, and a substrate cleaning device, such as an ion gun. The substrate can be rotated and tilted, for example, whereby only the tip of an emitter can be coated with a low work function material.

  2. PREFACE Surface Modifications and Functionalization of Materials for Biomedical Applications

    NASA Astrophysics Data System (ADS)

    Endrino, Jose Luis; Puértolas, Jose A.; Albella, Jose M.

    2010-11-01

    Conference photograph This special issue contains selected papers which were presented as invited and contributed communications at the workshop entitled 'Surface modification and functionalization of materials for biomedical applications' (BIO-COAT 2010) which was held on 24 June 2010 in Zaragoza (Spain). The surface of a material plays a major role in its interaction with the biological medium. Processes related to the mechanical stability of articular devices in contact, osseointegration, thrombogenicity, corrosion and leaching, or the inflammatory response of rejection of a material, are clearly conditioned by the surface properties. Therefore, the modification or functionalization of surfaces can have an important impact on these issues. New techniques for functionalization by thin film deposition or surface treatments help to improve superficial properties, while understanding the interaction of the surface-biological medium is critical for their application in new devices. Jointly organized by the Spanish Materials Research Society, BIO-COAT 2010 provided an open forum to discuss the progress and latest developments in thin film processing and the engineering of biomaterials. Invited lectures were particularly aimed at providing overviews on scientific topics and were given by recognized world-class scientists. Two of them have contributed with a proceedings article to this selected collection (articles 012001 and 012008). The contributed communications were focused on particular cutting-edge aspects of thin film science and functionalization technologies for biomaterials, showing the major scientific push of Spanish research groups in the field. The 2010 BIO-COAT conference was organized along four main topics: (1) functionalization and texture on surfaces, (2) tribology and corrosion, (3) the surface modification of biomaterials, and (4) surface-biological environment interactions. The papers published in this volume were accepted for publication after peer-review as are regular papers. The editor of this proceedings volume gratefully acknowledges all referees for their valuable work, sometimes working to quite short deadlines. Finally, BIO-COAT 2010 would not have been successful without the strong involvement and input of the local organizing committee in Zaragoza, and the support of the University of Zaragoza. We sincerely thank them all for their efforts. Jose L Endrino (Editor) Jose A Puértolas (Chairman) Jose M Albella (Chairman)

  3. Shape control of inorganic nanoparticles from solution.

    PubMed

    Wu, Zhaohui; Yang, Shuanglei; Wu, Wei

    2016-01-01

    Inorganic materials with controllable shapes have been an intensely studied subject in nanoscience over the past decades. Control over novel and anisotropic shapes of inorganic nanomaterials differing from those of bulk materials leads to unique and tunable properties for widespread applications such as biomedicine, catalysis, fuels or solar cells and magnetic data storage. This review presents a comprehensive overview of shape-controlled inorganic nanomaterials via nucleation and growth theory and the control of experimental conditions (including supersaturation, temperature, surfactants and secondary nucleation), providing a brief account of the shape control of inorganic nanoparticles during wet-chemistry synthetic processes. Subsequently, typical mechanisms for shape-controlled inorganic nanoparticles and the general shape of the nanoparticles formed by each mechanism are also expounded. Furthermore, the differences between similar mechanisms for the shape control of inorganic nanoparticles are also clearly described. The authors envision that this review will provide valuable guidance on experimental conditions and process control for the synthesis of inorganic nanoparticles with tunable shapes in the solution state. PMID:26696235

  4. Functionalized Cyclophanes Incorporated into Molecular Architectures and Mechanized Materials

    NASA Astrophysics Data System (ADS)

    Boyle, Megan Marie

    Supramolecular chemistry, the chemistry of the noncovalent bond beyond the molecule, has been utilized historically to organize the formation of novel compounds and topologies, including mechanically interlocked molecules (MIMs). Specifically, the host-guest complex between the cyclophane cyclobis(paraquat-p-phenylene) (CBPQT4+) and electron-rich guests has been exploited to template the formation of catenanes, rotaxanes and other topologically interesting molecules. By equipping CBPQT 4+ with new functional handles, previously unattainable topologies can be accessed. Moving beyond the synthesis of MIMs in solution, functionalizing the cyclophane enables the marriage of these existing topologies to different materials. In doing so, new properties can be obtained and new functions can be elicited. In this thesis, the functionalization of CBPQT4+ is featured in respect to a bioconjugate device that utilizes the cyclophane and a molecular Figure-of-Eight (Fo8). The DNA bioconjugate device is constructed characterized, and recognition properties are examined here. The donor-acceptor Fo8 is also synthesized and characterized here. The Fo8 possesses a structure that could not be attainable without the functionalized CBPQT4+ host. Furthermore, the resulting stereochemical implications and consequences of the Fo8 structure are presented.

  5. Optimum weight design of functionally graded material gears

    NASA Astrophysics Data System (ADS)

    Jing, Shikai; Zhang, He; Zhou, Jingtao; Song, Guohua

    2015-10-01

    Traditional gear weight optimization methods consider gear tooth number, module, face width or other dimension parameters of gear as design variables. However, due to the complicated form and geometric features peculiar to the gear, there will be large amounts of design parameters in gear design, and the influences of gear parameters changing on gear trains, transmission system and the whole equipment have to be taken into account, which increases the complexity of optimization problem. This paper puts forward to apply functionally graded materials (FGMs) to gears and then conduct the optimization. According to the force situation of gears, the material distribution form of FGM gears is determined. Then based on the performance parameters analysis of FGMs and the practical working demands for gears, a multi-objective optimization model is formed. Finally by using the goal driven optimization (GDO) method, the optimal material distribution is achieved, which makes gear weight and the maximum deformation be minimum and the maximum bending stress do not exceed the allowable stress. As an example, the applying of FGM to automotive transmission gear is conducted to illustrate the optimization design process and the result shows that under the condition of keeping the normal working performance of gear, the method achieves in greatly reducing the gear weight. This research proposes a FGM gears design method that is able to largely reduce the weight of gears by optimizing the microscopic material parameters instead of changing the macroscopic dimension parameters of gears, which reduces the complexity of gear weight optimization problem.

  6. Peptide Self-Assembly for Crafting Functional Biological Materials

    PubMed Central

    Matson, John B.; Zha, R. Helen; Stupp, Samuel I.

    2011-01-01

    Self-assembling, peptide-based scaffolds are frontrunners in the search for biomaterials with widespread impact in regenerative medicine. The inherent biocompatibility and cell signaling capabilities of peptides, in combination with control of secondary structure, has led to the development of a broad range of functional materials with potential for many novel therapies. More recently, membranes formed through complexation of peptide nanostructures with natural biopolymers have led to the development of hierarchically-structured constructs with potentially far-reaching applications in biology and medicine. In this review, we highlight recent advances in peptide-based gels and membranes, including work from our group and others. Specifically, we discuss the application of peptide-based materials in the regeneration of bone and enamel, cartilage, and the central nervous system, as well as the transplantation of islets, wound-healing, cardiovascular therapies, and treatment of erectile dysfunction after prostatectomy PMID:22125413

  7. Material Innovation in Advancing Organometal Halide Perovskite Functionality.

    PubMed

    Zheng, Fan; Saldana-Greco, Diomedes; Liu, Shi; Rappe, Andrew M

    2015-12-01

    Organometal halide perovskites (OMHPs) have garnered much attention recently for their unprecedented rate of increasing power conversion efficiency (PCE), positioning them as a promising basis for the next-generation photovoltaic devices. However, the gap between the rapid increasing PCE and the incomplete understanding of the structure-property-performance relationship prevents the realization of the true potential of OMHPs. This Perspective aims to provide a concise overview of the current status of OMHP research, highlighting the unique properties of OMHPs that are critical for solar applications but still not adequately explained. Stability and performance challenges of OMHP solar cells are discussed, calling upon combined experimental and theoretical efforts to address these challenges for pioneering commercialization of OMHP solar cells. Various material innovation strategies for improving the performance and stability of OMHPs are surveyed, showing that the OMHP architecture can serve as a promising and robust platform for the design and optimization of materials with desired functionalities. PMID:26631361

  8. Functionalized DNA materials for sensing and medical applications

    NASA Astrophysics Data System (ADS)

    Woolard, Dwight L.; Jensen, James O.

    2011-06-01

    The U.S. Army has strong interests in nanoscale architectures that enable enhanced extraction and controllable multiplication of the THz/IR regime spectral signatures associated with specific bio-molecular targets. Emerging DNAbased nano-assemblies (i.e., either materials or structural devices) will be discussed that realize novel sensing paradigms through the incorporation of organic and/or biological molecules such that they effect highly predictable and controllable changes into the electro-optical properties of the resulting superstructures. Results will be given to illustrate the utility of functionalized DNA materials in biological (and chemical) sensing, and to demonstrate how the basic science can be leveraged to study and develop synthetic antibodies, reporters and vaccines for future medical applications.

  9. Fluorescent Functionalized Mesoporous Silica for Radioactive Material Extraction

    SciTech Connect

    Li, Juan; Zhu, Kake; Shang, Jianying; Wang, Donghai; Nie, Zimin; Guo, Ruisong; Liu, Chongxuan; Wang, Zheming; Li, Xiaolin; Liu, Jun

    2012-08-01

    Mesoporous silica with covalently bound salicylic acid molecules incorporated in the structure was synthesized with a one-pot, co-condensation reaction at room temperature. The as-synthesized material has a large surface area, uniform particle size, and an ordered pore structure as determined by characterization with transmission electron microscopy, thermal gravimetric analysis, and infrared spectra, etc. Using the strong fluorescence and metal coordination capability of salicylic acid, functionalized mesoporous silica (FMS) was developed to track and extract radionuclide contaminants, such as uranyl [U(VI)] ions encountered in subsurface environments. Adsorption measurements showed a strong affinity of the FMS toward U(VI) with a Kd value of 105 mL/g, which is four orders of magnitude higher than the adsorption of U(VI) onto most of the sediments in natural environments. The new materials have a potential for synergistic environmental monitoring and remediation of the radionuclide U(VI) from contaminated subsurface environments.

  10. Hybrid materials of MCM-41 functionalized by lanthanide (Tb{sup 3+}, Eu{sup 3+}) complexes of modified meta-methylbenzoic acid: Covalently bonded assembly and photoluminescence

    SciTech Connect

    Li Ying; Yan Bing

    2008-05-15

    Novel organic-inorganic mesoporous hybrid materials were synthesized by linking lanthanide (Tb{sup 3+}, Eu{sup 3+}) complexes to the mesoporous MCM-41 through the modified meta-methylbenzoic acid (MMBA-Si) using co-condensation method in the presence of the cetyltrimethylammonium bromide (CTAB) surfactant as template. The luminescence properties of these resulting materials (denoted as Ln-MMBA-MCM-41, Ln=Tb, Eu) were characterized in detail, and the results reveal that luminescent mesoporous materials have high surface area, uniformity in the ordered mesoporous structure. Moreover, the mesoporous material covalently bonded Tb{sup 3+} complex (Tb-MMBA-MCM-41) exhibits the stronger characteristic emission of Tb{sup 3+} and longer lifetime than Eu-MMBA-MCM-41 due to the triplet state energy of organic legend MMBA-Si matches with the emissive energy level of Tb{sup 3+} very well. - Graphical abstract: Novel organic-inorganic mesoporous luminescent materials were synthesized by linking lanthanide (Tb{sup 3+}, Eu{sup 3+}) complexes to covalently bond the functionalized ordered mesoporous MCM-41 with modified meta-methylbenzoic acid (MMBA)-Si by co-condensation of tetraethoxysilane (TEOS) in the presence of the cetyltrimethylammonium bromide (CTAB) surfactant as template.

  11. Fabrication and application of advanced functional materials from lignincellulosic biomass

    NASA Astrophysics Data System (ADS)

    Hu, Sixiao

    This dissertation explored the conversion of lignocellulosic biomass into advanced functional materials and their potential applications. Lignocellulosic biomass represents an as-of-yet underutilized renewable source for not only biofuel production but also functional materials fabrication. This renewable source is a great alternative for fossil fuel based chemicals, which could be one of the solutions to energy crisis. In this work, it was demonstrated a variety of advanced materials including functional carbons, metal and silica nanoparticles could be derived from lignocellulosic biomass. Chapter 1 provided overall reviewed of the lignin structures, productions and its utilizations as plastics, absorbents and carbons, as well as the preparation of nano-structured silver, silica and silicon carbide/nitride from biomass. Chapter 2, 3 and 4 discussed the fabrication of highly porous carbons from isolated lignin, and their applications as electric supercapacitors for energy storage. In chapter 2, ultrafine porous carbon fibers were prepared via electrospinning followed by simultaneous carbonization and activation. Chapter 3 covered the fabrication of supercapacitor based on the porous carbon fibers and the investigation of their electrochemical performances. In chapter 4, porous carbon particulates with layered carbon nano plates structures were produced by simple oven-drying followed by simultaneous carbonization and activation. The effects of heat processing parameters on the resulting carbon structures and their electrochemical properties were discussed in details. Chapter 5 and 6 addressed the preparation of silver nanoparticles using lignin. Chapter 5 reported the synthesis, underlying kinetics and mechanism of monodispersed silver nanospheres with diameter less than 25 nm in aqueous solutions using lignin as dual reducing and capping agents. Chapter 6 covered the preparation of silver nanoparticles on electrospun celluloses ultrafine fibers using lignin as both binding and reducing agents. The efficiency of this synthetic protocol and the properties of resulting particles were examined. Chapter 7 reported the streamlined extraction of lignin/hemicelluloses and silica from rice straw and their subsequent conversion to activated carbon and monodispersed silica particles.

  12. Antimicrobial functions on cellulose materials introduced by anthraquinone vat dyes.

    PubMed

    Zhuo, Jingyuan; Sun, Gang

    2013-11-13

    Many anthraquinone compounds have exhibited light-active properties in solutions and on materials under UVA or fluorescent light exposure. Two anthraquinone derivatives were incorporated onto cotton fabrics by a vat dyeing process. The dyed fabrics demonstrated light-induced biocidal functions, and the functions were durable against laundering and long-term light exposure. The structures and surface morphologies of the dyed fabrics were examined by using fourier transform infrared (FTIR) spectroscopy and scanning electron microscopy (SEM). Mechanical properties of the fabrics were measured by using a tensile tester. The results revealed that the anthraquinone compounds have different light-activities, resulting in different surface and mechanical impacts on the cotton cellulose. PMID:24079962

  13. Density functional calculations on structural materials for nuclear energy applications and functional materials for photovoltaic energy applications (abstract only).

    PubMed

    Domain, C; Olsson, P; Becquart, C S; Legris, A; Guillemoles, J F

    2008-02-13

    Ab initio density functional theory calculations are carried out in order to predict the evolution of structural materials under aggressive working conditions such as cases with exposure to corrosion and irradiation, as well as to predict and investigate the properties of functional materials for photovoltaic energy applications. Structural metallic materials used in nuclear facilities are subjected to irradiation which induces the creation of large amounts of point defects. These defects interact with each other as well as with the different elements constituting the alloys, which leads to modifications of the microstructure and the mechanical properties. VASP (Vienna Ab initio Simulation Package) has been used to determine the properties of point defect clusters and also those of extended defects such as dislocations. The resulting quantities, such as interaction energies and migration energies, are used in larger scale simulation methods in order to build predictive tools. For photovoltaic energy applications, ab initio calculations are used in order to search for new semiconductors and possible element substitutions for existing ones in order to improve their efficiency. PMID:21693886

  14. Seventy-Five Percent Nephrectomy and the Disposition of Inorganic Mercury in 2,3-Dimercaptopropanesulfonic Acid-Treated Rats Lacking Functional Multidrug-Resistance Protein 2

    PubMed Central

    Bridges, Christy C.

    2010-01-01

    In the present study, we evaluated the disposition of inorganic mercury (Hg2+) in sham-operated and 75% nephrectomized (NPX) Wistar and transport-deficient (TR?) rats treated with saline or the chelating agent meso-2,3-dimercaptosuccinic acid (DMSA). Based on previous studies, DMSA and TR? rats were used as tools to examine the potential role of multidrug-resistance protein 2 (MRP2) in the disposition of Hg2+ during renal insufficiency. All animals were treated with a low dose (0.5 ?mol/kg i.v.) of mercuric chloride (HgCl2). At 24 and 28 h after exposure to HgCl2, matched groups of Wistar and TR? rats received normal saline or DMSA (intraperitoneally). Forty-eight hours after exposure to HgCl2, the disposition of Hg2+ was examined. A particularly notable effect of 75% nephrectomy in both strains of rats was enhanced renal accumulation of Hg2+, specifically in the outer stripe of the outer medulla. In addition, hepatic accumulation, fecal excretion, and blood levels of Hg2+ were enhanced in rats after 75% nephrectomy, especially in the TR? rats. Treatment with DMSA increased both the renal tubular elimination and urinary excretion of Hg2+ in all rats. DMSA did not, however, affect hepatic content of Hg2+, even in the 75% NPX TR? rats. We also show with real-time polymerase chain reaction that after 75% nephrectomy and compensatory renal growth, expression of MRP2 (only in Wistar rats) and organic anion transporter 1 is enhanced in the remaining functional proximal tubules. We conclude that MRP2 plays a significant role in the renal and corporal disposition of Hg2+ after a 75% reduction of renal mass. PMID:20032202

  15. Seventy-five percent nephrectomy and the disposition of inorganic mercury in 2,3-dimercaptopropanesulfonic acid-treated rats lacking functional multidrug-resistance protein 2.

    PubMed

    Zalups, Rudolfs K; Bridges, Christy C

    2010-03-01

    In the present study, we evaluated the disposition of inorganic mercury (Hg(2+)) in sham-operated and 75% nephrectomized (NPX) Wistar and transport-deficient (TR(-)) rats treated with saline or the chelating agent meso-2,3-dimercaptosuccinic acid (DMSA). Based on previous studies, DMSA and TR(-) rats were used as tools to examine the potential role of multidrug-resistance protein 2 (MRP2) in the disposition of Hg(2+) during renal insufficiency. All animals were treated with a low dose (0.5 mumol/kg i.v.) of mercuric chloride (HgCl(2)). At 24 and 28 h after exposure to HgCl(2), matched groups of Wistar and TR(-) rats received normal saline or DMSA (intraperitoneally). Forty-eight hours after exposure to HgCl(2), the disposition of Hg(2+) was examined. A particularly notable effect of 75% nephrectomy in both strains of rats was enhanced renal accumulation of Hg(2+), specifically in the outer stripe of the outer medulla. In addition, hepatic accumulation, fecal excretion, and blood levels of Hg(2+) were enhanced in rats after 75% nephrectomy, especially in the TR(-) rats. Treatment with DMSA increased both the renal tubular elimination and urinary excretion of Hg(2+) in all rats. DMSA did not, however, affect hepatic content of Hg(2+), even in the 75% NPX TR(-) rats. We also show with real-time polymerase chain reaction that after 75% nephrectomy and compensatory renal growth, expression of MRP2 (only in Wistar rats) and organic anion transporter 1 is enhanced in the remaining functional proximal tubules. We conclude that MRP2 plays a significant role in the renal and corporal disposition of Hg(2+) after a 75% reduction of renal mass. PMID:20032202

  16. Soft materials design via self assembly of functionalized icosahedral particles

    NASA Astrophysics Data System (ADS)

    Muthukumar, Vidyalakshmi Chockalingam

    In this work we simulate self assembly of icosahedral building blocks using a coarse grained model of the icosahedral capsid of virus 1m1c. With significant advancements in site-directed functionalization of these macromolecules [1], we propose possible application of such self-assembled materials for drug delivery. While there have been some reports on organization of viral particles in solution through functionalization, exploiting this behaviour for obtaining well-ordered stoichiometric structures has not yet been explored. Our work is in well agreement with the earlier simulation studies of icosahedral gold nanocrystals, giving chain like patterns [5] and also broadly in agreement with the wet lab works of Finn, M.G. et al., who have shown small predominantly chain-like aggregates with mannose-decorated Cowpea Mosaic Virus (CPMV) [22] and small two dimensional aggregates with oligonucleotide functionalization on the CPMV capsid [1]. To quantify the results of our Coarse Grained Molecular Dynamics Simulations I developed analysis routines in MATLAB using which we found the most preferable nearest neighbour distances (from the radial distribution function (RDF) calculations) for different lengths of the functional groups and under different implicit solvent conditions, and the most frequent coordination number for a virus particle (histogram plots further using the information from RDF). Visual inspection suggests that our results most likely span the low temperature limits explored in the works of Finn, M.G. et al., and show a good degree of agreement with the experimental results in [1] at an annealing temperature of 4°C. Our work also reveals the possibility of novel stoichiometric N-mer type aggregates which could be synthesized using these capsids with appropriate functionalization and solvent conditions.

  17. The functionalization of fullerenes and nanocarbon materials for photovoltaics and other applications

    E-print Network

    Han, Ggoch Ddeul (Ggoch Ddeul Grace)

    2015-01-01

    Fullerenes and other nanocarbon materials such as carbon nanotubes possess interesting chemical and physical properties. In this thesis, we explore various functionalization methods for nanocarbon materials and their ...

  18. DNA block copolymers: functional materials for nanoscience and biomedicine.

    PubMed

    Schnitzler, Tobias; Herrmann, Andreas

    2012-09-18

    We live in a world full of synthetic materials, and the development of new technologies builds on the design and synthesis of new chemical structures, such as polymers. Synthetic macromolecules have changed the world and currently play a major role in all aspects of daily life. Due to their tailorable properties, these materials have fueled the invention of new techniques and goods, from the yogurt cup to the car seat belts. To fulfill the requirements of modern life, polymers and their composites have become increasingly complex. One strategy for altering polymer properties is to combine different polymer segments within one polymer, known as block copolymers. The microphase separation of the individual polymer components and the resulting formation of well defined nanosized domains provide a broad range of new materials with various properties. Block copolymers facilitated the development of innovative concepts in the fields of drug delivery, nanomedicine, organic electronics, and nanoscience. Block copolymers consist exclusively of organic polymers, but researchers are increasingly interested in materials that combine synthetic materials and biomacromolecules. Although many researchers have explored the combination of proteins with organic polymers, far fewer investigations have explored nucleic acid/polymer hybrids, known as DNA block copolymers (DBCs). DNA as a polymer block provides several advantages over other biopolymers. The availability of automated synthesis offers DNA segments with nucleotide precision, which facilitates the fabrication of hybrid materials with monodisperse biopolymer blocks. The directed functionalization of modified single-stranded DNA by Watson-Crick base-pairing is another key feature of DNA block copolymers. Furthermore, the appropriate selection of DNA sequence and organic polymer gives control over the material properties and their self-assembly into supramolecular structures. The introduction of a hydrophobic polymer into DBCs in aqueous solution leads to amphiphilic micellar structures with a hydrophobic polymer core and a DNA corona. In this Account, we discuss selected examples of recent developments in the synthesis, structure manipulation and applications of DBCs. We present achievements in synthesis of DBCs and their amplification based on molecular biology techniques. We also focus on concepts involving supramolecular assemblies and the change of morphological properties by mild stimuli. Finally, we discuss future applications of DBCs. DBC micelles have served as drug-delivery vehicles, as scaffolds for chemical reactions, and as templates for the self-assembly of virus capsids. In nanoelectronics, DNA polymer hybrids can facilitate size selection and directed deposition of single-walled carbon nanotubes in field effect transistor (FET) devices. PMID:22726237

  19. Inorganic nanolayers: structure, preparation, and biomedical applications

    PubMed Central

    Saifullah, Bullo; Hussein, Mohd Zobir B

    2015-01-01

    Hydrotalcite-like compounds are two-dimensional inorganic nanolayers also known as clay minerals or anionic clays or layered double hydroxides/layered hydroxy salts, and have emerged as a single type of material with numerous biomedical applications, such as drug delivery, gene delivery, cosmetics, and biosensing. Inorganic nanolayers are promising materials due to their fascinating properties, such as ease of preparation, ability to intercalate different type of anions (inorganic, organic, biomolecules, and even genes), high thermal stability, delivery of intercalated anions in a sustained manner, high biocompatibility, and easy biodegradation. Inorganic nanolayers have been the focus for researchers over the last decade, resulting in widening application horizons, especially in the field of biomedical science. These nanolayers have been widely applied in drug and gene delivery. They have also been applied in biosensing technology, and most recently in bioimaging science. The suitability of inorganic nanolayers for application in drug delivery, gene delivery, biosensing technology, and bioimaging science makes them ideal materials to be applied for theranostic purposes. In this paper, we review the structure, methods of preparation, and latest advances made by inorganic nanolayers in such biomedical applications as drug delivery, gene delivery, biosensing, and bioimaging. PMID:26366081

  20. Materiality matters: Blurred boundaries and the domestication of functional foods

    PubMed Central

    Weiner, Kate; Will, Catherine

    2015-01-01

    Previous scholarship on novel foods, including functional foods, has suggested that they are difficult to categorise for both regulators and users. It is argued that they blur the boundary between ‘food' and ‘drug' and that uncertainties about the products create ‘experimental' or ‘restless' approaches to consumption. We investigate these uncertainties drawing on data about the use of functional foods containing phytosterols, which are licensed for sale in the EU for people wishing to reduce their cholesterol. We start from an interest in the products as material objects and their incorporation into everyday practices. We consider the scripts encoded in the physical form of the products through their regulation, production and packaging and find that these scripts shape but do not determine their use. The domestication of phytosterols involves bundling the products together with other objects (pills, supplements, foodstuffs). Considering their incorporation into different systems of objects offers new understandings of the products as foods or drugs. In their accounts of their practices, consumers appear to be relatively untroubled by uncertainties about the character of the products. We conclude that attending to materials and practices offers a productive way to open up and interrogate the idea of categorical uncertainties surrounding new food products. PMID:26157471

  1. Dynamic fracture of functionally graded magnetoelectroelastic composite materials

    SciTech Connect

    Stoynov, Y.; Dineva, P.

    2014-11-12

    The stress, magnetic and electric field analysis of multifunctional composites, weakened by impermeable cracks, is of fundamental importance for their structural integrity and reliable service performance. The aim is to study dynamic behavior of a plane of functionally graded magnetoelectroelastic composite with more than one crack. The coupled material properties vary exponentially in an arbitrary direction. The plane is subjected to anti-plane mechanical and in-plane electric and magnetic load. The boundary value problem described by the partial differential equations with variable coefficients is reduced to a non-hypersingular traction boundary integral equation based on the appropriate functional transform and frequency-dependent fundamental solution derived in a closed form by Radon transform. Software code based on the boundary integral equation method (BIEM) is developed, validated and inserted in numerical simulations. The obtained results show the sensitivity of the dynamic stress, magnetic and electric field concentration in the cracked plane to the type and characteristics of the dynamic load, to the location and cracks disposition, to the wave-crack-crack interactions and to the magnitude and direction of the material gradient.

  2. Theory of hydrogen migration in organic-inorganic halide perovskites.

    PubMed

    Egger, David A; Kronik, Leeor; Rappe, Andrew M

    2015-10-12

    Solar cells based on organic-inorganic halide perovskites have recently been proven to be remarkably efficient. However, they exhibit hysteresis in their current-voltage curves, and their stability in the presence of water is problematic. Both issues are possibly related to a diffusion of defects in the perovskite material. By using first-principles calculations based on density functional theory, we study the properties of an important defect in hybrid perovskites-interstitial hydrogen. We show that differently charged defects occupy different crystal sites, which may allow for ionization-enhanced defect migration following the Bourgoin-Corbett mechanism. Our analysis highlights the structural flexibility of organic-inorganic perovskites: successive iodide displacements, combined with hydrogen bonding, enable proton diffusion with low migration barriers. These findings indicate that hydrogen defects can be mobile and thus highly relevant for the performance of perovskite solar cells. PMID:26073061

  3. Theory of Hydrogen Migration in Organic–Inorganic Halide Perovskites**

    PubMed Central

    Egger, David A; Kronik, Leeor; Rappe, Andrew M

    2015-01-01

    Solar cells based on organic–inorganic halide perovskites have recently been proven to be remarkably efficient. However, they exhibit hysteresis in their current–voltage curves, and their stability in the presence of water is problematic. Both issues are possibly related to a diffusion of defects in the perovskite material. By using first-principles calculations based on density functional theory, we study the properties of an important defect in hybrid perovskites—interstitial hydrogen. We show that differently charged defects occupy different crystal sites, which may allow for ionization-enhanced defect migration following the Bourgoin–Corbett mechanism. Our analysis highlights the structural flexibility of organic–inorganic perovskites: successive iodide displacements, combined with hydrogen bonding, enable proton diffusion with low migration barriers. These findings indicate that hydrogen defects can be mobile and thus highly relevant for the performance of perovskite solar cells. PMID:26073061

  4. Simple hydrazone building blocks for complicated functional materials.

    PubMed

    Tatum, Luke A; Su, Xin; Aprahamian, Ivan

    2014-07-15

    CONSPECTUS: The ability to selectively and effectively control various molecular processes via specific stimuli is a hallmark of the complexity of biological systems. The development of synthetic structures that can mimic such processes, even on the fundamental level, is one of the main goals of supramolecular chemistry. Having this in mind, there has been a foray of research in the past two decades aimed at developing molecular architectures, whose properties can be modulated using external inputs. In most cases, reversible conformational, configurational, or translational motions, as well as bond formation or cleavage reactions have been used in such modulations, which are usually initiated using inputs including, irradiation, metalation, or changes in pH. This research activity has led to the development of a diverse array of impressive adaptive systems that have been used in showcasing the potential of molecular switches and machines. That being said, there are still numerous obstacles to be tackled in the field, ranging from difficulties in getting molecular switches to communicate and work together to complications in integrating and interfacing them with surfaces and bulk materials. Addressing these challenges will necessitate the development of creative new approaches in the field, the improvement of the currently available materials, and the discovery of new molecular switches. This Account will describe how our quest to design new molecular switches has led us to the development of structurally simple systems that can be used for complicated functions. Our focus on the modular and tunable hydrazone functional group was instigated by the desire to simplify the structure and design of molecular switches in order to circumvent multistep synthesis. We hypothesized that by avoiding this synthetic bottleneck, which is one of the factors that hinder fast progress in the field, we can expedite the development and deployment of our adaptive materials. It should be noted though that designing structurally simple switches cannot be an end goal by itself! Therefore, we showed that our molecules can be used in applications that are beyond a simple molecular switching event (i.e., the control of the photophysical properties of liquid crystals and multistep switching cascades). While focusing on these switches, we discovered that the hydrazones can be easily transformed, using straightforward one-step reactions, into visible light activated azo switches, and two different families of fluorophores that can be used in sensing applications. These findings demonstrate that our approach of developing simple systems for sophisticated functions is not limited to the field of molecular switches and machines but can also encompass other adaptive materials. PMID:24766362

  5. A micromechanical study of residual stresses in functionally graded materials

    SciTech Connect

    Dao, M.; Gu, P.; Maewal, A.; Asaro, R.J.

    1997-08-01

    A physically based computational micromechanics model is developed to study random and discrete microstructures in functionally graded materials (FGMs). The influences of discrete microstructure on residual stress distributions at grain size level are examined with respect to material gradient and FGM volume percentage (within a ceramic-FGM-metal three-layer structure). Both thermoelastic and thermoplastic deformation are considered, and the plastic behavior of metal grains is modeled at the single crystal level using crystal plasticity theory. The results are compared with those obtained using a continuous model which does not consider the microstructural randomness and discreteness. In an averaged sense both the micromechanics model and the continuous model give practically the same macroscopic stresses; whereas the discrete micromechanics model predicts fairly high residual stress concentrations at the grain size level (i.e., higher than 700 MPa in 5--6 vol% FGM grains) with only a 300 C temperature drop in a Ni-Al{sub 2}O{sub 3} FGM system. Statistical analysis shows that the residual stress concentrations are insensitive to material gradient and FGM volume percentage. The need to consider microstructural details in FGM microstructures is evident. The results obtained provide some insights for improving the reliability of FGMs against fracture and delamination.

  6. Inorganic-organic separators for alkaline batteries

    NASA Technical Reports Server (NTRS)

    Sheibley, D. W. (inventor)

    1978-01-01

    A flexible separator is reported for use between the electrodes of Ni-Cd and Ni-Zn batteries using alkaline electrolytes. The separator was made by coating a porous substrate with a battery separator composition. The coating material included a rubber-based resin copolymer, a plasticizer and inorganic and organic fillers which comprised 55% by volume or less of the coating as finally dried. One or more of the filler materials, whether organic or inorganic, is preferably active with the alkaline electrolyte to produce pores in the separator coating. The plasticizer was an organic material which is hydrolyzed by the alkaline electrolyte to improve conductivity of the separator coating.

  7. Utilising inorganic nanocarriers for gene delivery.

    PubMed

    Loh, Xian Jun; Lee, Tung-Chun; Dou, Qingqing; Deen, G Roshan

    2015-12-15

    The delivery of genetic materials into cells to elicit cellular responses has been extensively studied by biomaterials scientists globally. Many materials such as lipids, peptides, viruses, synthetically modified cationic polymers and certain inorganic nanomaterials could be used to complex the negatively charged plasmids and deliver the formed package into cells. The recent literature on the delivery of genetic materials utilising inorganic nanoparticles is carefully examined in this review. We have picked out the most relevant references and concisely summarised the findings with illustrated examples. We further propose alternative approaches and suggest future pathways towards the practical use of multifunctional nanocarriers. PMID:26484365

  8. Bioinspiration from fish for smart material design and function

    NASA Astrophysics Data System (ADS)

    Lauder, G. V.; Madden, P. G. A.; Tangorra, J. L.; Anderson, E.; Baker, T. V.

    2011-09-01

    Fish are a potentially rich source of inspiration for the design of smart materials. Fish exemplify the use of flexible materials to generate forces during locomotion, and a hallmark of fish functional design is the use of body and fin deformation to power propulsion and maneuvering. As a result of nearly 500 million years of evolutionary experimentation, fish design has a number of interesting features of note to materials engineers. In this paper we first provide a brief general overview of some key features of the mechanical design of fish, and then focus on two key properties of fish: the bilaminar mechanical design of bony fish fin rays that allows active muscular control of curvature, and the role of body flexibility in propulsion. After describing the anatomy of bony fish fin rays, we provide new data on their mechanical properties. Three-point bending tests and measurement of force inputs to and outputs from the fin rays show that these fin rays are effective displacement transducers. Fin rays in different regions of the fin differ considerably in their material properties, and in the curvature produced by displacement of one of the two fin ray halves. The mean modulus for the proximal (basal) region of the fin rays was 1.34 GPa, but this varied from 0.24 to 3.7 GPa for different fin rays. The distal fin region was less stiff, and moduli for the different fin rays measured varied from 0.11 to 0.67 GPa. These data are similar to those for human tendons (modulus around 0.5 GPa). Analysis of propulsion using flexible foils controlled using a robotic flapping device allows investigation of the effect of altering flexural stiffness on swimming speed. Flexible foils with the leading edge moved in a heave show a distinct peak in propulsive performance, while the addition of pitch input produces a broad plateau where the swimming speed is relatively unaffected by the flexural stiffness. Our understanding of the material design of fish and the control of tissue stiffness is still in its infancy, and the development of smart materials to assist in investigating the active control of stiffness and in the construction of robotic fish-like devices is a key challenge for the near future.

  9. 10 CFR 1023.1 - Introductory material on the Board and its functions.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... Introductory material on the Board and its functions. 1023.1 Section 1023... Introductory material on the Board and its functions. (a) The Energy Board of...authorities necessary for the Board to maintain its separate operations and decisional...

  10. Harvesting bioenergy with rationally designed complex functional materials

    NASA Astrophysics Data System (ADS)

    Kuang, Liangju

    A key challenge in renewable energy is to capture, convert and store solar power with earth-abundant materials and environmentally benign technologies. The goal of this thesis is to develop rationally designed complex functional materials for bio-renewable energy applications. On one hand, photoconversion membrane proteins (MPs) are nature's nanoengineering feats for renewable energy management. Harnessing their functions in synthetic systems could help understand, predict, and ultimately control matter and energy at the nanoscale. This is particularly enticing in the post-genome era as recombinant or cell-free expression of many MPs with high yields becomes possible. However, the labile nature of lipid bilayers renders them unsuitable for use in a broad range of engineered systems. A knowledge gap exists about how to design robust synthetic nanomembranes as lipid-bilayer-mimics to support MP functions and how to direct hierarchical MP reconstitution into those membranes to form 2-D or 3-D ordered proteomembrane arrays. Our studies on proteorhodopsin (PR) and bacterial reaction center (BRC), the two light-harvesting MPs, reveal that a charge-interaction-directed reconstitution (CIDR) mechanism induces spontaneous reconstitution of detergent-solubilized MPs into various amphiphilic block copolymer membranes, many of which have far superior stability than lipid bilayers. Our preliminary data also suggest MPs are not enslaved by the biological membranes they derive from; rather, the chemically nonspecific material properties of MP-supporting membranes may act as allosteric regulators. Versatile chemical designs are possible to modulate the conformational energetics of MPs, hence their transport performance in synthetic systems. On the other hand, microalgae are widely regarded as a sustainable feedstock for biofuel production. Microalgae-derived biofuels have not been commercialized yet because current technologies for microalgae dewatering add a huge cost to the final product, and present a major bottleneck. We propose to solve the microalgae dewatering problem in the context of controlling colloidal stability, where inter-algal potential is tuned via surface engineering of novel coagulation agents. We report here a nanoparticle-pinched polymer brush design that combines two known colloidal destabilization agents (e.g., nanoparticle and polymer) into one system, and allows the use of an external field (e.g., magnetic force) to not only modulate inter-algae pair potentials, but also facilitate retrieval of the coagulation agents to be reused after algal oil extraction. We will discuss our extensive data on the preparation of well-defined nanoparticle-pinched polymer brushes, their structure-dependent coagulation performance on both fresh water and marine microalgae species, and their re-suability for continuous cycles of microalgae farming and harvesting.

  11. Size and Crystallinity in Protein-Templated Inorganic Nanoparticles

    SciTech Connect

    Jolley, Craig C.; Uchida, Masaki; Reichhardt, Courtney; Harrington, Richard; Kang, Sebyung; Klem, Michael T.; Parise, John B.; Douglas, Trevor

    2010-12-01

    Protein cages such as ferritins and virus capsids have been used as containers to synthesize a wide variety of protein-templated inorganic nanoparticles. While identification of the inorganic crystal phase has been successful in some cases, very little is known about the detailed nanoscale structure of the inorganic component. We have used pair distribution function analysis of total X-ray scattering to measure the crystalline domain size in nanoparticles of ferrihydrite, {gamma}-Fe{sub 2}O{sub 3}, Mn{sub 3}O{sub 4}, CoPt, and FePt grown inside 24-meric ferritin cages from H. sapiens and P. furiosus. The material properties of these protein-templated nanoparticles are influenced by processes at a variety of length scales: the chemistry of the material determines the precise arrangement of atoms at very short distances, while the interior volume of the protein cage constrains the maximum nanoparticle size attainable. At intermediate length scales, the size of coherent crystalline domains appears to be constrained by the arrangement of crystal nucleation sites on the interior of the cage. On the basis of these observations, some potential synthetic strategies for the control of crystalline domain size in protein-templated nanoparticles are suggested.

  12. Ultrathin coatings of nanoporous materials as property enhancements for advanced functional materials.

    SciTech Connect

    Coker, Eric Nicholas

    2010-11-01

    This report summarizes the findings of a five-month LDRD project funded through Sandia's NTM Investment Area. The project was aimed at providing the foundation for the development of advanced functional materials through the application of ultrathin coatings of microporous or mesoporous materials onto the surface of substrates such as silicon wafers. Prior art teaches that layers of microporous materials such as zeolites may be applied as, e.g., sensor platforms or gas separation membranes. These layers, however, are typically several microns to several hundred microns thick. For many potential applications, vast improvements in the response of a device could be realized if the thickness of the porous layer were reduced to tens of nanometers. However, a basic understanding of how to synthesize or fabricate such ultra-thin layers is lacking. This report describes traditional and novel approaches to the growth of layers of microporous materials on silicon wafers. The novel approaches include reduction of the quantity of nutrients available to grow the zeolite layer through minimization of solution volume, and reaction of organic base (template) with thermally-oxidized silicon wafers under a steam atmosphere to generate ultra-thin layers of zeolite MFI.

  13. ATRP in the design of functional materials for biomedical applications

    PubMed Central

    Siegwart, Daniel J.; Oh, Jung Kwon; Matyjaszewski, Krzysztof

    2013-01-01

    Atom Transfer Radical Polymerization (ATRP) is an effective technique for the design and preparation of multifunctional, nanostructured materials for a variety of applications in biology and medicine. ATRP enables precise control over macromolecular structure, order, and functionality, which are important considerations for emerging biomedical designs. This article reviews recent advances in the preparation of polymer-based nanomaterials using ATRP, including polymer bioconjugates, block copolymer-based drug delivery systems, cross-linked microgels/nanogels, diagnostic and imaging platforms, tissue engineering hydrogels, and degradable polymers. It is envisioned that precise engineering at the molecular level will translate to tailored macroscopic physical properties, thus enabling control of the key elements for realized biomedical applications. PMID:23525884

  14. Centrifugally-assisted combustion synthesis of functionally-graded materials

    SciTech Connect

    Lai, W.; Munir, Z.A.; McCoy, B.J.; Risbud, S.H.

    1997-02-01

    Functionally graded materials (FGM`s) have been prepared by a variety of techniques, including combustion synthesis, and the use of a centrifugal force in this method of synthesis has been demonstrated previously. However, in the earlier work, a centrifugal force was applied to investigate the changes in the dynamics of self-propagating combustion waves or to deposit coatings on the inside surfaces of pipes. The use of a centrifugal force to investigate the formation of FGM`s has not been reported previously and is the focus of this communication. In this work, the authors have chosen thermite reactions to investigate the feasibility of FGM formation by centrifugally-assisted combustion synthesis.

  15. Functional nucleic acid entrapment in sol-gel derived materials.

    PubMed

    Carrasquilla, Carmen; Brennan, John D

    2013-10-01

    Functional nucleic acids (FNAs) are single-stranded DNA or RNA molecules, typically generated through in vitro selection, that have the ability to act as receptors for target molecules (aptamers) or perform catalysis of a chemical reaction (deoxyribozymes and ribozymes). Fluorescence-signaling aptamers and deoxyribozymes have recently emerged as promising biological recognition and signaling elements, although little has been done to evaluate their potential for solid-phase assays, particularly with species made of RNA due to their lack of chemical stability and susceptibility to nuclease attack. Herein, we present a detailed overview of the methods utilized for solid-phase immobilization of FNAs using a sol-gel entrapment method that can provide protection from nuclease degradation and impart long-term chemical stability to the FNA reporter systems, while maintaining their signaling capabilities. This article will also provide a brief review of the results of such entrapment studies involving fluorescence-signaling versions of a DNA aptamer, selected RNA-cleaving deoxyribozymes, and two different RNA aptamers in a series of sol-gel derived composites, ranging from highly polar silica to hydrophobic methylsilsesquioxane-based materials. Given the ability to produce sol-gel derived materials in a variety of configurations, particularly as thin film coatings on electrodes, optical fibers, and other devices, this entrapment method should provide a useful platform for numerous solid-phase FNA-based biosensing applications. PMID:24025165

  16. Density functional study of silver defects in telluride thermoelectric materials

    NASA Astrophysics Data System (ADS)

    Ryu, Byungki; Oh, Min-Wook; Park, Su-Dong

    2015-03-01

    Silver impurity in telluride thermoelectric materials forms various defect and impurity structures, such as AgSb rich nanoregion in Ag-Sb-Pb-Te, Ag2Te and metallic silver in PbTe. To understand the atomic, electronic, energetic, and diffusion properties of silver impurities in telluride systems, we have performed the density functional theory and density functional perturbation theory calculations of silver doped PbTe. Under Te and Ag rich condition, silver telluride impurity phase or Ag-dimer defects are expected to be easily formed. Under Te poor condition, silver point defects are calculated to be easily formed and they are more stable than native point defects of PbTe, implying that silver point defect might be the major dopant responsible for the carrier generation in PbTe. We also calculated the diffusion coefficient and diffusion length of silver point defect in PbTe. Based on the results, we discussed the electrical and thermoelectric properties of silver doped PbTe. This work was supported by the National Institute of Supercomputing and Network/Korea Institute of Science and Technology Information with supercomputing resources including technical support (KSC-2014-C1-022).

  17. Aspect Ratio Effect of Functionalized/Non-Functionalized Multiwalled Carbon Nanotubes on the Mechanical Properties of Cementitious Materials 

    E-print Network

    Ashour, Ahmad

    2012-10-19

    compared to other composite materials, a limited amount of research has been conducted on the CNTs/cement composites. In order to investigate how the aspect ratio of functionalized/non-functionalized MWCNTs affects the mechanical properties...

  18. Efficient inorganic solid solar cells composed of perovskite and PbS quantum dots

    NASA Astrophysics Data System (ADS)

    Li, Yi; Zhu, Jun; Huang, Yang; Wei, Junfeng; Liu, Feng; Shao, Zhipeng; Hu, Linhua; Chen, Shuanghong; Yang, Shangfeng; Tang, Junwang; Yao, Jianxi; Dai, Songyuan

    2015-05-01

    Lead halide perovskite solar cells have attracted great interest due to their high efficiency and simple fabrication process. However, the high efficiency heavily relies on expensive organic hole-transporting materials (OHTMs) such as 2,2',7,7'-tetrakis(N,N-di-p-methoxyphenylamine)-9,9'-spirobifluorene (spiro-MeOTAD), it is preferable to replace these expensive OHTMs by inorganic and low cost materials. Here, we report colloidal PbS quantum dots synthesized by a facile method and used as the inorganic hole-transporting material in a hybrid perovskite solar cell. By controlling the crystalline morphology of the perovskite capping layer, the recombination process is significantly retarded. Furthermore, a pure inorganic solar cell prepared by a two-step process demonstrated a nearly 8% power conversion efficiency due to efficient charge separation by a cascade of junctions and retarding charge recombination by a void-free capping layer. The stability of the inorganic solar cell was also tested with a little decay observed within ca. 100 h.Lead halide perovskite solar cells have attracted great interest due to their high efficiency and simple fabrication process. However, the high efficiency heavily relies on expensive organic hole-transporting materials (OHTMs) such as 2,2',7,7'-tetrakis(N,N-di-p-methoxyphenylamine)-9,9'-spirobifluorene (spiro-MeOTAD), it is preferable to replace these expensive OHTMs by inorganic and low cost materials. Here, we report colloidal PbS quantum dots synthesized by a facile method and used as the inorganic hole-transporting material in a hybrid perovskite solar cell. By controlling the crystalline morphology of the perovskite capping layer, the recombination process is significantly retarded. Furthermore, a pure inorganic solar cell prepared by a two-step process demonstrated a nearly 8% power conversion efficiency due to efficient charge separation by a cascade of junctions and retarding charge recombination by a void-free capping layer. The stability of the inorganic solar cell was also tested with a little decay observed within ca. 100 h. Electronic supplementary information (ESI) available: The UV-visible absorption spectrum of the perovskite based on a one-step method before and after spinning PbS QDs. Photovoltaic characteristics of perovskite solar cells as a function of spin-coating number for PbS QDs. See DOI: 10.1039/c5nr00420a

  19. A novel inorganic-organic nanohybrid material H4SiW12O40/pyridino-MCM-41 as efficient catalyst for the preparation of 1-amidoalkyl-2-naphthols under solvent-free conditions.

    PubMed

    Tayebee, R; Amini, M M; Akbari, M; Aliakbari, A

    2015-05-28

    A new inorganic-organic nanohybrid material H4SiW12O40/pyridino-MCM-41 was prepared and performed as an efficient, eco-friendly, and highly recyclable catalyst for the one-pot multi-component synthesis of different substituted 1-amidoalkyl-2-naphthols under solvent-free conditions. The nanohybrid catalyst was prepared through electrostatic anchoring of Keggin heteropolyacid H4SiW12O40 on the surface of MCM-41 nanoparticles modified by N-[3-(triethoxysilyl)propyl]isonicotinamide. The prepared material was characterized by XRD, SEM, EDX, UV-Vis, DTA-TGA, DLS, and FT-IR spectroscopy. Findings confirmed that the heteropolyacid is well dispersed on the surface of the solid support and its structure is preserved after immobilization on the TPI modified MCM-41 nanoparticles. The recovered catalyst was easily recycled for at least seven runs without considerable loss of catalytic activity. PMID:25923593

  20. Fabrication, Characterization and Modeling of Functionally Graded Materials

    NASA Astrophysics Data System (ADS)

    Lee, Po-Hua

    In the past few decades, a number of theoretical and experimental studies for design, fabrication and performance analysis of solar panel systems (photovoltaic/thermal systems) have been documented. The existing literature shows that the use of solar energy provides a promising solution to alleviate the shortage of natural resources and the environmental pollution associated with electricity generation. A hybrid solar panel has been invented to integrate photovoltaic (PV) cells onto a substrate through a functionally graded material (FGM) with water tubes cast inside, through which water flow serves as both a heat sink and a solar heat collector. Due to the unique and graded material properties of FGMs, this novel design not only supplies efficient thermal harvest and electrical production, but also provides benefits such as structural integrity and material efficiency. In this work, a sedimentation method has been used to fabricate aluminum (Al) and high-density polyethylene (HDPE) FGMs. The size effect of aluminum powder on the material gradation along the depth direction is investigated. Aluminum powder or the mixture of Al and HDPE powder is thoroughly mixed and uniformly dispersed in ethanol and then subjected to sedimentation. During the sedimentation process, the concentration of Al and HDPE particles temporally and spatially changes in the depth direction due to the non-uniform motion of particles; this change further affects the effective viscosity of the suspension and thus changes the drag force of particles. A Stokes' law based model is developed to simulate the sedimentation process, demonstrate the effect of manufacturing parameters on sedimentation, and predict the graded microstructure of deposition in the depth direction. In order to improve the modeling for sedimentation behavior of particles, the Eshelby's equivalent inclusion method (EIM) is presented to determine the interaction between particles, which is not considered in a Stokes' law based model. This method is initially applied to study the case of one drop moving in a viscous fluid; the solution recovers the closed form classic solution when the drop is spherical. Moreover, this method is general and can be applied to the cases of different drop shapes and the interaction between multiple drops. The translation velocities of the drops depend on the relative position, the center-to-center distance of drops, the viscosity and size of drops. For the case of a pair of identical spherical drops, the present method using a linear approximation of the eigenstrain rate has provided a very close solution to the classic explicit solution. If a higher order of the polynomial form of the eigenstrain rate is used, one can expect a more accurate result. To meet the final goal of mass production of the aforementioned Al-HDPE FGM, a faster and more economical material manufacturing method is proposed through a vibration method. The particle segregation of larger aluminum particles embedded in the concentrated suspension of smaller high-density polyethylene is investigated under vibration with different frequencies and magnitudes. Altering experimental parameters including time and amplitude of vibration, the suspension exhibits different particle segregation patterns: uniform-like, graded and bi-layered. For material characterization, small cylinder films of Al-HDPE system FGM are obtained after the stages of dry, melt and solidification. Solar panel prototypes are fabricated and tested at different water flow rates and solar irradiation intensities. The temperature distribution in the solar panel is measured and simulated to evaluate the performance of the solar panel. Finite element simulation results are very consistent with the experimental data. The understanding of heat transfer in the hybrid solar panel prototypes gained through this study will provide a foundation for future solar panel design and optimization.

  1. Synthesis of Novel Polypeptide-Silica Hybrid Materials through Surface-Initiated N-carboxyanhydride Polymerization 

    E-print Network

    Lunn, Jonathan D.

    2011-08-08

    There is an increasing demand for materials that are physically robust, easily recovered, and able to perform a wide variety of chemical functions. By combining hard and soft matter synergistically, organic-inorganic hybrid ...

  2. A Mapping of the Electron Localization Function for Earth Materials

    SciTech Connect

    Gibbs, Gerald V.; Cox, David F.; Ross, Nancy; Crawford, T Daniel; Burt, Jason; Rosso, Kevin M.

    2005-06-01

    The electron localization function, ELF, generated for a number of geometry-optimized earth materials, provides a graphical representation of the spatial localization of the probability electron density distribution as embodied in domains ascribed to localized bond and lone pair electrons. The lone pair domains, displayed by the silica polymorphs quartz, coesite and cristobalite, are typically banana-shaped and oriented perpendicular to the plane of the SiOSi angle at ~0.60 Å from the O atom on the reflex side of the angle. With decreasing angle, the domains increase in magnitude, indicating an increase in the nucleophilic character of the O atom, rendering it more susceptible to potential electrophilic attack. The Laplacian isosurface maps of the experimental and theoretical electron density distribution for coesite substantiates the increase in the size of the domain with decreasing angle. Bond pair domains are displayed along each of the SiO bond vectors as discrete concave hemispherically-shaped domains at ~0.70 Å from the O atom. For more closed-shell ionic bonded interactions, the bond and lone pair domains are often coalesced, resulting in concave hemispherical toroidal-shaped domains with local maxima centered along the bond vectors. As the shared covalent character of the bonded interactions increases, the bond and lone pair domains are better developed as discrete domains. ELF isosurface maps generated for the earth materials tremolite, diopside, talc and dickite display banana-shaped lone pair domains associated with the bridging O atoms of SiOSi angles and concave hemispherical toroidal bond pair domains associated with the nonbridging ones. The lone pair domains in dickite and talc provide a basis for understanding the bonded interactions between the adjacent neutral layers. Maps were also generated for beryl, cordierite, quartz, low albite, forsterite, wadeite, åkermanite, pectolite, periclase, hurlbutite, thortveitite and vanthoffite. Strategies are reviewed for finding potential H docking sites in the silica polymorphs and related materials. As observed in an earlier study, the ELF is capable of generating bond and lone pair domains that are similar in number and arrangement to those provided by Laplacian and deformation electron density distributions. The formation of the bond and lone pair domains in the silica polymorphs and the progressive decrease in the SiO length as the value of the electron density at the bond critical point increases indicates that the SiO bonded interaction has a substantial component of covalent character.

  3. Science Update: Inorganic Chemistry

    ERIC Educational Resources Information Center

    Rawls, Rebecca

    1978-01-01

    This first in a series of articles describing the state of the art of various branches of chemistry reviews inorganic chemistry, including bioinorganic, photochemistry, organometallic, and solid state chemistries. (SL)

  4. Minerals, Inorganic Substances

    MedlinePLUS

    ... Fit-Friendly Worksites Program Requirements Fit-Friendly Resources Minerals, Inorganic Substances Updated:Feb 26,2014 Fluoridation No ... been implicated as possible contributors to cardiovascular disease. Zinc, copper, cadmium and lead, individually or in combination, ...

  5. Inorganic Chemistry Solutions to Semiconductor Nanocrystal Problems

    SciTech Connect

    Alvarado, Samuel R.; Guo, Yijun; Ruberu, T. Purnima A.; Tavasoli, Elham; Vela, Javier

    2014-03-15

    The optoelectronic and chemical properties of semiconductor nanocrystals heavily depend on their composition, size, shape and internal structure, surface functionality, etc. Available strategies to alter these properties through traditional colloidal syntheses and ligand exchange methods place a premium on specific reaction conditions and surfactant combinations. In this invited review, we apply a molecular-level understanding of chemical precursor reactivity to reliably control the morphology, composition and intimate architecture (core/shell vs. alloyed) of semiconductor nanocrystals. We also describe our work aimed at achieving highly selective, low-temperature photochemical methods for the synthesis of semiconductor–metal and semiconductor–metal oxide photocatalytic nanocomposites. In addition, we describe our work on surface modification of semiconductor nanocrystal quantum dots using new approaches and methods that bypass ligand exchange, retaining the nanocrystal's native ligands and original optical properties, as well as on spectroscopic methods of characterization useful in determining surface ligand organization and chemistry. Using recent examples from our group and collaborators, we demonstrate how these efforts have lead to faster, wider and more systematic application of semiconductor nanocrystal-based materials to biological imaging and tracking, and to photocatalysis of unconventional substrates. We believe techniques and methods borrowed from inorganic chemistry (including coordination, organometallic and solid state chemistry) have much to offer in reaching a better understanding of the synthesis, functionalization and real-life application of such exciting materials as semiconductor nanocrystals (quantum dots, rods, tetrapods, etc.).

  6. Transient Elastodynamic Crack Growth in Functionally Graded Materials

    SciTech Connect

    Chalivendra, Vijaya B.

    2008-02-15

    A generalized elastic solution for an arbitrarily propagating transient crack in Functionally Graded Materials (FGMs) is obtained through an asymptotic analysis. The shear modulus and mass density of the FGM are assumed to vary exponentially along the gradation direction. The mode-mixity due to the inclination of property gradient with respect to the propagating crack tip is accommodated in the analysis through superposition of the opening and shear modes. First three terms of out of plane displacement field and its gradients about the crack tip are obtained in powers of radial coordinates, with the coefficients depending on the time rate of change of crack tip speed and stress intensity factors. Using these displacement fields, the effect of transient stress intensity factors and acceleration on synthetic contours of constant out of plane displacement under both opening and mixed mode loading conditions has been studied. These contours show that the transient terms cause significant spatial variation on out of plane displacements around the crack tip. Therefore, in studying dynamic fracture of FGMs, it is appropriate to include the transient terms in the field equations for the situations of sudden variation of stress intensity factor or crack tip velocity.

  7. Dislocation punching from interfaces in functionally-graded materials

    SciTech Connect

    Taya, M.; Lee, J.K.; Mori, T.

    1997-06-01

    A new dislocation punching model for a functionally graded material (FGM) subjected to a temperature change is proposed, using Eshelby`s model. FGM, consisting of several layers, is deposited on a ceramic substrate. Two types of microstructures are examined for a layer: one consists of a metal matrix and ceramic particles and the other of a ceramic matrix and metal particles. An elastic energy is evaluated when plastic strain, in addition to thermal mismatch strain, is introduced in the metal phase. The work dissipated by the plastic deformation is also calculated. From the condition that the reduction in the elastic energy is larger than the work dissipated, a critical thermal mismatch strain to induce stress relaxation is determined. The magnitude of the plastic strain is also determined, when the relaxation occurs. The theory is applied to a model FGM consisting of mixtures of Pd and Al{sub 2}O{sub 3} on an Al{sub 2}O{sub 3} substrate.

  8. Molecularly imprinted hydrogels as functional active packaging materials.

    PubMed

    Benito-Peña, Elena; González-Vallejo, Victoria; Rico-Yuste, Alberto; Barbosa-Pereira, Letricia; Cruz, José Manuel; Bilbao, Ainhoa; Alvarez-Lorenzo, Carmen; Moreno-Bondi, María Cruz

    2016-01-01

    This paper describes the synthesis of novel molecularly imprinted hydrogels (MIHs) for the natural antioxidant ferulic acid (FA), and their application as packaging materials to prevent lipid oxidation of butter. A library of MIHs was synthesized using a synthetic surrogate of FA, 3-(4-hydroxy-3-methoxyphenyl)propionic acid (HFA), as template molecule, ethyleneglycol dimethacrylate (EDMA) as cross-linker, and 1-allylpiperazine (1-ALPP) or 2-(dimethylamino)ethyl methacrylate (DMAEMA), in combination with 2-hydroxyethyl methacrylate (HEMA) as functional monomers, at different molar concentrations. The DMAEMA/HEMA-based MIHs showed the greatest FA loading capacity, while the 1-ALLP/HEMA-based polymers exhibited the highest imprinting effect. During cold storage, FA-loaded MIHs protected butter from oxidation and led to TBARs values that were approximately half those of butter stored without protection and 25% less than those recorded for butter covered with hydrogels without FA, potentially extending the shelf life of butter. Active packaging is a new field of application for MIHs with great potential in the food industry. PMID:26213001

  9. Data-mined similarity function between material compositions

    E-print Network

    Yang, Lusann

    A new method for assessing the similarity of material compositions is described. A similarity measure is important for the classification and clustering of compositions. The similarity of the material compositions is ...

  10. Functional Graphenic Materials Via a Johnson?Claisen Rearrangement

    E-print Network

    Swager, Timothy M.

    Current research in materials has devoted much attention to graphene, with a considerable amount of the chemical manipulation going through the oxidized state of the material, known as graphene oxide (GO). In this report, ...

  11. Organic/Inorganic Complex Pigments: Ancient Colors Maya Blue

    SciTech Connect

    Polette-Niewold, L.A.; Manciu, F.S.; Torres, B.; Alvarado, M.; Jr.; Chianelli, R.R.

    2009-06-04

    Maya Blue is an ancient blue pigment composed of palygorskite clay and indigo. It was used by the ancient Maya and provides a dramatic background for some of the most impressive murals throughout Mesoamerica. Despite exposure to acids, alkalis, and chemical solvents, the color of the Maya Blue pigment remains unaltered. The chemical interaction between palygorskite and indigo form an organic/inorganic complex with the carbonyl oxygen of the indigo bound to a surface Al{sup 3+} in the Si-O lattice. In addition indigo will undergo an oxidation to dehydroindigo during preparation. The dehydro-indigo molecule forms a similar but stronger complex with the Al{sup 3+}. Thus, Maya Blue varies in color due to the mixed indigo/dehydroindigo complex. The above conclusions are the result of application of multiple techniques (X-ray diffraction, differential thermal analysis/thermal gravimetric analysis, high resolution transmission electron microscopy, scanning electron microscopy, infrared and Raman spectroscopy) to the characterization of the organic/inorganic complex. A picture of the bonding of the organic molecule to the palygorskite surface forming a surface complex is developed and supported by the results of density functional theory calculations. We also report that other organic molecules such as thioindigo form similar organic/inorganic complexes thus, opening an entirely new class of complex materials for future applications.

  12. Study of nonproportionality in the light yield of inorganic scintillators

    SciTech Connect

    Singh, Jai

    2011-07-15

    Using a phenomenological approach, the light yield is derived for inorganic scintillators as a function of the rates of linear, bimolecular, and Auger processes occurring in the electron track initiated by an x ray or a {gamma}-ray photon. A relation between the track length and incident energy is also derived. It is found that the nonproportionality in the light yield can be eliminated if either nonlinear processes of interaction among the excited electrons, holes, and excitons can be eliminated from occurring or the high density situation can be relieved by diffusion of carriers from the track at a faster rate than the rate of activation of nonlinear processes. The influence of the track length and radius on the yield nonproportionality is discussed in view of the known experimental results. Inventing new inorganic scintillating materials with high carrier mobility can lead to a class of proportional inorganic scintillators. Results agree qualitatively with experimental results for the dependence of light yield on the incident energy.

  13. Identifying Optimal Inorganic Nanomateirals for Hybrid Solar Cells

    SciTech Connect

    Xiang, H.; Wei, S. H.; Gong, X. G.

    2009-01-01

    As a newly developed photovoltaic technology, organic-inorganic hybrid solar cells have attracted great interest because of the combined advantages from both components. An ideal inorganic acceptor should have a band gap of about 1.5 eV and energy levels of frontier orbitals matching those of the organic polymer in hybrid solar cells. Hybrid density functional calculations are performed to search for optimal inorganic nanomaterials for hybrid solar sells based on poly(3-hexylthiophene) (P3HT). Our results demonstrate that InSb quantum dots or quantum wires can have a band gap of about 1.5 eV and highest occupied molecular orbital level about 0.4 eV lower than P3HT, indicating that they are good candidates for use in hybrid solar cells. In addition, we predict that chalcopyrite MgSnSb{sub 2} quantum wire could be a low-cost material for realizing high-efficiency hybrid solar cells.

  14. Pulse thermal processing of functional materials using directed plasma arc

    DOEpatents

    Ott, Ronald D. (Knoxville, TN); Blue, Craig A. (Knoxville, TN); Dudney, Nancy J. (Knoxville, TN); Harper, David C. (Kingston, TN)

    2007-05-22

    A method of thermally processing a material includes exposing the material to at least one pulse of infrared light emitted from a directed plasma arc to thermally process the material, the pulse having a duration of no more than 10 s.

  15. Fabrication of Functionally Graded-cellular Structures of Cement-based Materials by Co-

    E-print Network

    Paulino, Glaucio H.

    Fabrication of Functionally Graded-cellular Structures of Cement-based Materials by Co- extrusion Y-extrusion of layered cement-based materials. The paste flow in the barrel and the die land in a ram extruder should. The functionally graded cellular structures of cement-based materials were successfully fabricated by co

  16. Reconstruction of spectral function from effective permittivity of a composite material using rational function approximations

    NASA Astrophysics Data System (ADS)

    Zhang, Dali; Cherkaev, Elena

    2009-08-01

    The paper deals with the problem of reconstruction of microstructural information from known effective complex permittivity of a composite material. A numerical method for recovering geometric information from measurements of frequency dependent effective complex permittivity is developed based on Stieltjes analytic representation of the effective permittivity tensor of a two-component mixture. We derive the Stieltjes representation for the effective permittivity of the medium using the eigenfunction expansion of the solution of a boundary-value problem. The spectral function in this representation contains all information about the microgeometry of the mixture. A discrete approximation of the spectral measure is derived from a rational (Padé) approximation followed by its partial fractions decomposition. The approach is based on the least squares minimization with regularization constraints provided by the spectral properties of the operator. The method is applied to calculation of volume fractions of the components in a mixture of two materials in a Bruggeman effective medium analytic model which has a continuous spectral density and to analytical models of two-phase composites with coated cylindrical and ellipsoidal inclusions. The numerical results of reconstruction of spectral measure for a mixture of silver and silicon dioxide and a composite of magnesium and magnesium fluoride show good agreement between theoretical and predicted values. The approach is applicable to geological materials, biocomposites, porous media, etc.

  17. 46 CFR 151.50-20 - Inorganic acids.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 46 Shipping 5 2011-10-01 2011-10-01 false Inorganic acids. 151.50-20 Section 151.50-20 Shipping... BULK LIQUID HAZARDOUS MATERIAL CARGOES Special Requirements § 151.50-20 Inorganic acids. (a)(1) Gravity..., but in no case shall the design pressure be less than that indicated as follows: Fluorosilicic...

  18. 46 CFR 151.50-20 - Inorganic acids.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 46 Shipping 5 2014-10-01 2014-10-01 false Inorganic acids. 151.50-20 Section 151.50-20 Shipping... BULK LIQUID HAZARDOUS MATERIAL CARGOES Special Requirements § 151.50-20 Inorganic acids. (a)(1) Gravity..., but in no case shall the design pressure be less than that indicated as follows: Fluorosilicic...

  19. 46 CFR 151.50-20 - Inorganic acids.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 46 Shipping 5 2013-10-01 2013-10-01 false Inorganic acids. 151.50-20 Section 151.50-20 Shipping... BULK LIQUID HAZARDOUS MATERIAL CARGOES Special Requirements § 151.50-20 Inorganic acids. (a)(1) Gravity..., but in no case shall the design pressure be less than that indicated as follows: Fluorosilicic...

  20. 46 CFR 151.50-20 - Inorganic acids.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 46 Shipping 5 2012-10-01 2012-10-01 false Inorganic acids. 151.50-20 Section 151.50-20 Shipping... BULK LIQUID HAZARDOUS MATERIAL CARGOES Special Requirements § 151.50-20 Inorganic acids. (a)(1) Gravity..., but in no case shall the design pressure be less than that indicated as follows: Fluorosilicic...

  1. Nanomoulding of Functional Materials, a Versatile Complementary Pattern Replication Method to Nanoimprinting

    PubMed Central

    Battaglia, Corsin; Söderström, Karin; Escarré, Jordi; Haug, Franz-Josef; Despeisse, Matthieu; Ballif, Christophe

    2013-01-01

    We describe a nanomoulding technique which allows low-cost nanoscale patterning of functional materials, materials stacks and full devices. Nanomoulding combined with layer transfer enables the replication of arbitrary surface patterns from a master structure onto the functional material. Nanomoulding can be performed on any nanoimprinting setup and can be applied to a wide range of materials and deposition processes. In particular we demonstrate the fabrication of patterned transparent zinc oxide electrodes for light trapping applications in solar cells. PMID:23380874

  2. Nanoporous delafossite CuAlO2 from inorganic/polymer double gels: a desirable high-surface-area p-type transparent electrode material.

    PubMed

    Das, Barun; Renaud, Adèle; Volosin, Alex M; Yu, Lei; Newman, Nathan; Seo, Dong-Kyun

    2015-02-01

    Nanoporous structures of a p-type semiconductor, delafossite CuAlO(2), with a high crystallinity have been fabricated through an inorganic/polymer double-gel process and characterized for the first time via Mott-Schottky measurements. The effect of the precursor concentration, calcination temperature, and atmosphere were examined to achieve high crystallinity and photoelectrochemical properties while maximizing the porosity. The optical properties of the nanoporous CuAlO(2) are in good agreement with the literature with an optical band gap of 3.9 eV, and the observed high electrical conductivity and hole concentrations conform to highly crystalline and well-sintered nanoparticles observed in the product. The Mott-Schottky plot from the electrochemical impedance spectroscopy studies indicates a flat-band potential of 0.49 V versus Ag/AgCl. It is concluded that CuAlO(2) exhibits band energies very close to those of NiO but with electrical properties very desirable in the fabrication of photoelectrochemical devices including dye-sensitized solar cells. PMID:25584858

  3. Synthesis, crystal structure and characterization of a new organic-inorganic hybrid material: [C6H16N2O]SbCl5

    NASA Astrophysics Data System (ADS)

    Aloui, Z.; Ferretti, V.; Abid, S.; Rzaigui, M.; Lefebvre, F.; Ben Nasr, C.

    2015-05-01

    The present paper undertakes the study of [C6H16N2O]SbCl5 which is a new hybrid compound. It is synthesized and characterized by single-crystal X-ray diffraction, thermal analysis, IR and solid state NMR spectroscopies. The centrosymmetric compound crystallizes in the monoclinic space group P21/n, with the following unit cell parameters: a = 9.8519(2), b = 8.8345(2), c = 17.3087(4) Å, ? = 102.3(1)° and Z = 4. The atomic arrangement shows an alternation of organic and inorganic entities. The cohesion between these entities is performed via N-H⋯Cl and O-H⋯Cl hydrogen bonding to form a three-dimensional network. The 13C CP-MAS NMR spectrum is in agreement with the X-ray structure. Infrared and Raman spectra at room temperature are recorded in the 4000-400 and 500-100 cm-1 frequency regions respectively. This study confirms the presence of the organic cation [C6H16N2]2+ and of the [SbCl5]2- anion. DFT calculations allow the attribution of the carbon peaks to the different atoms.

  4. TELEFUN: A Pragmatic Approach to Functional Learning Materials Development

    ERIC Educational Resources Information Center

    Fox, James

    1978-01-01

    This paper traces the development of a function-based module, TELEFUN, produced to teach telephone English to Francophone public servants in Canada. Telephone discourse is analyzed, and a number of techniques, including Function Frames and Function Dials, are described. (CFM)

  5. Simultaneous dynamic electrical and structural measurements of functional materials

    NASA Astrophysics Data System (ADS)

    Vecchini, C.; Thompson, P.; Stewart, M.; Muñiz-Piniella, A.; McMitchell, S. R. C.; Wooldridge, J.; Lepadatu, S.; Bouchenoire, L.; Brown, S.; Wermeille, D.; Bikondoa, O.; Lucas, C. A.; Hase, T. P. A.; Lesourd, M.; Dontsov, D.; Cain, M. G.

    2015-10-01

    A new materials characterization system developed at the XMaS beamline, located at the European Synchrotron Radiation Facility in France, is presented. We show that this new capability allows to measure the atomic structural evolution (crystallography) of piezoelectric materials whilst simultaneously measuring the overall strain characteristics and electrical response to dynamically (ac) applied external stimuli.

  6. SAXS in inorganic and bioinspired research.

    PubMed

    Stawski, Tomasz M; Benning, Liane G

    2013-01-01

    In situ and time-resolved structural information about emergent microstructures that progressively develop during the formation of inorganic or biologically mediated solid phases from solution is fundamental for understanding of the mechanisms driving complex precipitation reactions, for example, during biomineralization. In this brief chapter, we present the use of small- and wide-angle X-ray scattering (SAXS and WAXS) techniques and show how SAXS can be used to gather structural information on the nanoscale properties of the de novo-forming entities. We base the discussion on several worked examples of inorganic materials such as calcium carbonate, silica, and perovskite-type titanates. PMID:24188764

  7. Functional Nanofibers via Electospinning: New Materials and Processes

    NASA Astrophysics Data System (ADS)

    Manasco, Joshua Lee

    Cyclodextrins are fascinating, amphiphilic molecules that are of considerable interest due to their ability to be used in a variety of applications ranging from pharmaceuticals and cosmetics to foods and agriculture. These are ring-shaped sugar molecules possess a hydrophobic cavity and a hydrophilic exterior which imparts them water solubility. There are three main types of naturally occurring cyclodextrins namely alpha-, beta- and gamma- CD which have 6, 7 and 8 member rings, respectively. Owing to their hydrophobic interior, cyclodextrin molecules encapsulate hydrophobic guest molecules (from small to macromolecules) to form host-guest supermolecular structures. Chemically modified CDs are often preferred to the natural forms, particularly methylated (MbetaCD) and hydroxypropylated (HPbetaCD) cyclodextrins, for their enhanced solubility and chemical stability. Electrostatic spinning (electrospinning) of nanofibers has drawn significant research attention in recent decades. This technique involves the stretching of a polymer solution or melt in a high electric field to produce fibers on the nanoscale. These 1-Dimensional nanostructures possess extraordinary surface-to-weight ratio and find applications that vary from filtration membranes and tissue scaffolding materials to drug delivery and many others. The scope of this research attempts to leverage the unique features of CDs with the high aspect ratio of nanofibers to create functional nanomaterials. The present study can be divided into three sections. In the first part, we establish that CDs can be electrospun without the need for a "carrier" polymer. This discovery may serve to extend the horizon of what is currently considered "electrospinnable" from macromolecules now to small molecules. The ability to electrospin CDs led to their incorporation of other polymers to create bicomponent fibers with poly (vinyl alcohol) (PVA) and polyacrylonitrile (PAN). In the case of PVA we demonstrate the ability to not only to control the fiber properties based on PVA/CD ratio, but also crosslink these fibers to create water resistant fiber mats. Furthermore, the use of these fibers as rapid dissolving membranes for drug delivery is explored. Additionally, CDs are investigated for use as a porogen for PAN and carbon fibers. We find that CDs are particularly good candidates for us as porogens due to their amorphous nature and versatility to be dissolved in various solvent system. By nature, solution electrospinning is a low-throughput, solvent intensive process. In the last part we attempt to alleviate this issue by designing an extrusion based melt electrospinning device. We show that submicron fibers of polycaprolactone are possible through this technique without the use of organic solvents.

  8. A stochastic micromechanical model for elastic properties of functionally graded materials

    E-print Network

    Rahman, Sharif

    characteristics of elastic mechanical prop- erties of an isotropic functionally graded material (FGM) subject probabilistic descriptors of effective FGM properties. Four numerical examples involving statistical proper and probability density functions of effective mechanical properties of FGM illustrate the proposed stochastic

  9. Crystallinity of inorganic films grown by atomic layer deposition: Overview and general trends

    NASA Astrophysics Data System (ADS)

    Miikkulainen, Ville; Leskelä, Markku; Ritala, Mikko; Puurunen, Riikka L.

    2013-01-01

    Atomic layer deposition (ALD) is gaining attention as a thin film deposition method, uniquely suitable for depositing uniform and conformal films on complex three-dimensional topographies. The deposition of a film of a given material by ALD relies on the successive, separated, and self-terminating gas-solid reactions of typically two gaseous reactants. Hundreds of ALD chemistries have been found for depositing a variety of materials during the past decades, mostly for inorganic materials but lately also for organic and inorganic-organic hybrid compounds. One factor that often dictates the properties of ALD films in actual applications is the crystallinity of the grown film: Is the material amorphous or, if it is crystalline, which phase(s) is (are) present. In this thematic review, we first describe the basics of ALD, summarize the two-reactant ALD processes to grow inorganic materials developed to-date, updating the information of an earlier review on ALD [R. L. Puurunen, J. Appl. Phys. 97, 121301 (2005)], and give an overview of the status of processing ternary compounds by ALD. We then proceed to analyze the published experimental data for information on the crystallinity and phase of inorganic materials deposited by ALD from different reactants at different temperatures. The data are collected for films in their as-deposited state and tabulated for easy reference. Case studies are presented to illustrate the effect of different process parameters on crystallinity for representative materials: aluminium oxide, zirconium oxide, zinc oxide, titanium nitride, zinc zulfide, and ruthenium. Finally, we discuss the general trends in the development of film crystallinity as function of ALD process parameters. The authors hope that this review will help newcomers to ALD to familiarize themselves with the complex world of crystalline ALD films and, at the same time, serve for the expert as a handbook-type reference source on ALD processes and film crystallinity.

  10. Probing the nanoscale interaction forces and elastic properties of organic and inorganic materials using force-distance (F-D) spectroscopy

    NASA Astrophysics Data System (ADS)

    Vincent, Abhilash

    Due to their therapeutic applications such as radical scavenging, MRI contrast imaging, Photoluminescence imaging, drug delivery, etc., nanoparticles (NPs) have a significant importance in bio-nanotechnology. The reason that prevents the utilizing NPs for drug delivery in medical field is mostly due to their biocompatibility issues (incompatibility can lead to toxicity and cell death). Changes in the surface conditions of NPs often lead to NP cytotoxicity. Investigating the role of NP surface properties (surface charges and surface chemistry) on their interactions with biomolecules (Cells, protein and DNA) could enhance the current understanding of NP cytotoxicity. Hence, it is highly beneficial to the nanotechnology community to bring more attention towards the enhancement of surface properties of NPs to make them more biocompatible and less toxic to biological systems. Surface functionalization of NPs using specific ligand biomolecules have shown to enhance the protein adsorption and cellular uptake through more favorable interaction pathways. Cerium oxide NPs (CNPs also known as nanoceria) are potential antioxidants in cell culture models and understanding the nature of interaction between cerium oxide NPs and biological proteins and cells are important due to their therapeutic application (especially in site specific drug delivery systems). The surface charges and surface chemistry of CNPs play a major role in protein adsorption and cellular uptake. Hence, by tuning the surface charges and by selecting proper functional molecules on the surface, CNPs exhibiting strong adhesion to biological materials can be prepared. By probing the nanoscale interaction forces acting between CNPs and protein molecules using Atomic Force Microscopy (AFM) based force-distance (F-D) spectroscopy, the mechanism of CNP-protein adsorption and CNP cellular uptake can be understood more quantitatively. The work presented in this dissertation is based on the application of AFM in studying the interaction forces as well as the mechanical properties of nanobiomaterials. The research protocol employed in the earlier part of the dissertation is specifically aimed to understand the operation of F-D spectroscopy technique. The elastic properties of thin films of silicon dioxide NPs were investigated using F-D spectroscopy in the high force regime of few 100 nN to 1 microN. Here, sol-gel derived porous nanosilica thin films of varying surface morphology, particle size and porosity were prepared through acid and base catalyzed process. AFM nanoindentation experiments were conducted on these films using the F-D spectroscopy mode and the nanoscale elastic properties of these films were evaluated. The major contribution of this dissertation is a study exploring the interaction forces acting between CNPs and transferrin proteins in picoNewton scale regime using the force-distance spectroscopy technique. This study projects the importance of obtaining appropriate surface charges and surface chemistry so that the NP can exhibit enhanced protein adsorption and NP cellular uptake.

  11. Green's functions for a semi-infinite transversely isotropic piezothermoelastic material

    NASA Astrophysics Data System (ADS)

    Hou, Peng-Fei; Zhou, Xu-Hong; He, Yong-Jun

    2007-10-01

    Based on the compact general solution of transversely isotropic piezoelectric material, which is expressed in mono-harmonic functions, and employing the trial-and-error method, the three-dimensional Green function for a steady point heat source in a semi-infinite piezoelectric material is presented by four newly induced mono-harmonic functions. All components of the coupled field are expressed in terms of elementary functions and are convenient to use. Numerical results are given graphically by contours.

  12. Functional properties of whey protein and its application in nanocomposite materials and functional foods

    NASA Astrophysics Data System (ADS)

    Walsh, Helen

    Whey is a byproduct of cheese making; whey proteins are globular proteins which can be modified and polymerized to add functional benefits, these benefits can be both nutritional and structural in foods. Modified proteins can be used in non-foods, being of particular interest in polymer films and coatings. Food packaging materials, including plastics, can linings, interior coatings of paper containers, and beverage cap sealing materials, are generally made of synthetic petroleum based compounds. These synthetic materials may pose a potential human health risk due to presence of certain chemicals such as Bisphenol A (BPA). They also add to environmental pollution, being difficult to degrade. Protein-based materials do not have the same issues as synthetics and so can be used as alternatives in many packaging types. As proteins are generally hydrophilic they must be modified structurally and their performance enhanced by the addition of waterproofing agents. Polymerization of whey proteins results in a network, adding both strength and flexibility. The most interesting of the food-safe waterproofing agents are the (large aspect ratio) nanoclays. Nanoclays are relatively inexpensive, widely available and have low environmental impact. The clay surface can be modified to make it organophilic and so compatible with organic polymers. The objective of this study is the use of polymerized whey protein (PWP), with reinforcing nanoclays, to produce flexible surface coatings which limit the transfer of contents while maintaining food safety. Four smectite and kaolin type clays, one treated and three natural were assessed for strengthening qualities and the potential waterproofing and plasticizing benefits of other additives were also analyzed. The nutritional benefits of whey proteins can also be used to enhance the protein content of various foodstuffs. Drinkable yogurt is a popular beverage in the US and other countries and is considered a functional food, especially when produced with probiotic bacteria. Carbonation was applied to a drinkable yogurt to enhance its benefits. This process helps reduce the oxygen levels in the foodstuff thus potentially being advantageous to the microaerophilic probiotic bacteria while simultaneously producing a product, somewhat similar to kefir, which has the potential to fill a niche in the functional foods market. Yogurt was combined with a syrup to reduce its viscosity, making it drinkable, and also to allow infusion of CO2. This dilution reduced the protein content of the drink and so whey protein concentrate was added to increase levels in the final product. High-methoxyl pectins were used to provide stability by reducing the tendency of the proteins to sediment out. The objectives of this study were to develop a manufacturing technology for drinkable carbonated symbiotic yogurts, and to evaluate their physicochemical properties. Two flavors of yogurt drink, pomegranate and vanilla, were formulated containing inulin as prebiotic, along with probiotic bacteria, producing symbiotic dairy beverages.

  13. New functional polymers for sensors, smart materials and solar cells

    E-print Network

    Lobez Comeras, Jose Miguel

    2012-01-01

    Organic polymers can be used as the active component of sensors, smart materials, chemical-delivery systems and the active layer of solar cells. The rational design and modification of the chemical structure of polymers ...

  14. Organic-inorganic hybrid lead iodide perovskite with zero-dipole-moment guanidinium (GA =[C(NH2)3]+) cations: a Density Functional based analysis

    NASA Astrophysics Data System (ADS)

    Giorgi, Giacomo; Fujisawa, Jun-Ichi; Segawa, Hiroshi; Yamashita, Koichi

    2015-03-01

    Mixed organic-inorganic halide perovskites have been reported to have superior performances and unique features [2, 3] when used as light harvesters in photovoltaics. Interestingly, they can undergo several assembling procedures like sensitization and thin-film architecture. The latter one has been anyway recently reported to be affected by a noticeable hysteresis in the J - V curves at slow scan rate. No conclusive reasons for such behaviour have been provided so far. By means of an ab-initio campaign of calculations, we predict possible chemical solutions based on the replacement of the widely employed methylammonium (MA =CH3NH3+) cation with cations with reduced dipole moment, thus less sensitive to any applied external bias.

  15. Polyelectrolyte multilayers as nanostructured templates for inorganic synthesis

    E-print Network

    Wang, Tom Chih-Hung, 1973-

    2002-01-01

    Thin film nanocomposites consisting of inorganic matter embedded within a soft polymeric matrix on the nanometer length scale are an important class of materials with potential application in optoelectronics and photonics, ...

  16. Charting the complete elastic properties of inorganic crystalline compounds

    E-print Network

    de Jong, Maarten

    The elastic constant tensor of an inorganic compound provides a complete description of the response of the material to external stresses in the elastic limit. It thus provides fundamental insight into the nature of the ...

  17. Cluster-Expanded Solids: A Strategy for Assembling Functional Porous Materials

    SciTech Connect

    Long, Jeffrey R.

    2008-10-31

    This grant provided (partial) support for the research efforts of three graduate students and two undergraduate students. The intention of the program was to explore the use of molecular precursors in generating functional porous materials with precisely tailored structures and properties. Prior work in our laboratory had demonstrated the feasibility of employing face-capped octahedral clusters of the type [Re{sub 6}Q{sub 8}(CN){sub 6}]{sup 3-/4-} (Q = S, Se, Te) in the expansion of known metal-cyanide frameworks. For example, the use of [Re{sub 6}Se{sub 8}(CN){sub 6}]{sup 4-} as a reactant in place of [Fe(CN){sub 6}]{sup 4-} resulted in formation of Fe{sub 4}[Re{sub 6}Se{sub 8}(CN){sub 6}]{sub 3}·36H{sub 2}O, featuring an expanded form of the porous three-dimensional framework of Prussian blue (Fe{sub 4}[Fe(CN){sub 6}]{sub 3}·14H{sub 2}O). This compound could be dehydrated without loss of integrity, and the increase in void volume significantly enhances its capacity as a molecular sieve, enabling absorption of larger molecules. For this project, we continued with our efforts to devise new routes to microporous coordination solids that function as molecular sieves, sensors, or catalysts. In particular, our focus was on: (i) the synthesis of new molecular precursors of specific utility for such purposes, and (ii) attempts to incorporate these and existing molecular precursors into new coordination solids. Investigations of the terminal ligand substitution chemistry of the carbon-centered, trigonal prismatic cluster [W{sub 6}CCl{sub 18}]{sup 2-} generated the solvated species [W{sub 6}CCl{sub 12}(DMF){sub 6}]{sup 2+} and [W{sub 6}CCl{sub 12}(py){sub 6}]{sup 2+}, as well as the potential framework building units [W{sub 6}C(CN){sub 18}]{sup 3-}, [W6CCl{sub 12}(pyrazine){sub 6}]{sup 2+}, [W6CCl{sub 12}(4-cyanopyridine){sub 6}]{sup 2+}, and [W{sub 6}CCl{sub 12}(4,4??-bipyridine){sub 6}]{sup 2+}. Efforts to produce microporous magnets capable of performing magnetic separations led to characterization of the microporous Prussian blue analogues CsNi[Cr(CN){sub 6}] and Cr{sub 3}[Cr(CN){sub 6}]{sub 2}·6H{sub 2}O. With BET surface areas of 370 m{sup 2}/g and 390 m{sup 2}/g, respectively, these compounds exhibit show ferrimagnetic ordering at temperatures of 65 and 220 K, respectively, the highest ordering temperatures yet observed for any microporous magnet. Efforts to produce actinide-based cluster building units were also undertaken, as were experiments probing the reactivity of new metal-organic frameworks possessing coordinatively-unsaturated metal centers. This research further provided an excellent opportunity for training graduate and undergraduate students in the synthesis and characterization of inorganic materials.

  18. Lead and compounds (inorganic)

    Integrated Risk Information System (IRIS)

    Lead and compounds ( inorganic ) ; CASRN 7439 - 92 - 1 Human health assessment information on a chemical substance is included in the IRIS database only after a comprehensive review of toxicity data , as outlined in the IRIS assessment development process . Sections I ( Health Hazard Assessments for

  19. Negative thermal expansion in functional materials: controllable thermal expansion by chemical modifications.

    PubMed

    Chen, Jun; Hu, Lei; Deng, Jinxia; Xing, Xianran

    2015-06-01

    Negative thermal expansion (NTE) is an intriguing physical property of solids, which is a consequence of a complex interplay among the lattice, phonons, and electrons. Interestingly, a large number of NTE materials have been found in various types of functional materials. In the last two decades good progress has been achieved to discover new phenomena and mechanisms of NTE. In the present review article, NTE is reviewed in functional materials of ferroelectrics, magnetics, multiferroics, superconductors, temperature-induced electron configuration change and so on. Zero thermal expansion (ZTE) of functional materials is emphasized due to the importance for practical applications. The NTE functional materials present a general physical picture to reveal a strong coupling role between physical properties and NTE. There is a general nature of NTE for both ferroelectrics and magnetics, in which NTE is determined by either ferroelectric order or magnetic one. In NTE functional materials, a multi-way to control thermal expansion can be established through the coupling roles of ferroelectricity-NTE, magnetism-NTE, change of electron configuration-NTE, open-framework-NTE, and so on. Chemical modification has been proved to be an effective method to control thermal expansion. Finally, challenges and questions are discussed for the development of NTE materials. There remains a challenge to discover a "perfect" NTE material for each specific application for chemists. The future studies on NTE functional materials will definitely promote the development of NTE materials. PMID:25864730

  20. Probabilistic Fracture Analysis of Functionally Graded Materials -Part II: Implementation and

    E-print Network

    Paulino, Glaucio H.

    analyses are performed for investigating uncertain fracture re- sponse of Functionally Graded Material (FGM for FGM (FE-FGM), which was previously developed at the University of Illinois at Urbana-Champaign [2 responses of functionally graded material (FGM) structures. By integrating a structural reliability method

  1. Mixed-Mode Crack Propagation in Functionally Graded Materials Jeong-Ho Kim1,a

    E-print Network

    Paulino, Glaucio H.

    Mixed-Mode Crack Propagation in Functionally Graded Materials Jeong-Ho Kim1,a and Glaucio H method. Interaction integral method. Crack propagation. Abstract. This paper presents numerical simulation of mixed-mode crack propagation in functionally graded materials by means of a remeshing algorithm

  2. Optimal Experiment Design for Thermal Characterization of Functionally Graded Materials

    NASA Technical Reports Server (NTRS)

    Cole, Kevin D.

    2003-01-01

    The purpose of the project was to investigate methods to accurately verify that designed , materials meet thermal specifications. The project involved heat transfer calculations and optimization studies, and no laboratory experiments were performed. One part of the research involved study of materials in which conduction heat transfer predominates. Results include techniques to choose among several experimental designs, and protocols for determining the optimum experimental conditions for determination of thermal properties. Metal foam materials were also studied in which both conduction and radiation heat transfer are present. Results of this work include procedures to optimize the design of experiments to accurately measure both conductive and radiative thermal properties. Detailed results in the form of three journal papers have been appended to this report.

  3. Inorganic-organic thin implant coatings deposited by lasers.

    PubMed

    Sima, Felix; Davidson, Patricia M; Dentzer, Joseph; Gadiou, Roger; Pauthe, Emmanuel; Gallet, Olivier; Mihailescu, Ion N; Anselme, Karine

    2015-01-14

    The lifetime of bone implants inside the human body is directly related to their osseointegration. Ideally, future materials should be inspired by human tissues and provide the material structure-function relationship from which synthetic advanced biomimetic materials capable of replacing, repairing, or regenerating human tissues can be produced. This work describes the development of biomimetic thin coatings on titanium implants to improve implant osseointegration. The assembly of an inorganic-organic biomimetic structure by UV laser pulses is reported. The structure consists of a hydroxyapatite (HA) film grown onto a titanium substrate by pulsed-laser deposition (PLD) and activated by a top fibronectin (FN) coating deposited by matrix-assisted pulsed laser evaporation (MAPLE). A pulsed KrF* laser source (? = 248 nm, ? = 25 ns) was employed at fluences of 7 and 0.7J/cm(2) for HA and FN transfer, respectively. Films approximately 1500 and 450 nm thick were obtained for HA and FN, respectively. A new cryogenic temperature-programmed desorption mass spectrometry analysis method was employed to accurately measure the quantity of immobilized protein. We determined that less than 7 ?g FN per cm(2) HA surface is adequate to improve adhesion, spreading, and differentiation of osteoprogenitor cells. We believe that the proposed fabrication method opens the door to combining and immobilizing two or more inorganic and organic materials on a solid substrate in a well-defined manner. The flexibility of this method enables the synthesis of new hybrid materials by simply tailoring the irradiation conditions according to the thermo-physical properties of the starting materials. PMID:25485841

  4. Inorganic-based proton conductive composite membranes for elevated temperature and reduced relative humidity PEM fuel cells

    NASA Astrophysics Data System (ADS)

    Wang, Chunmei

    Proton exchange membrane (PEM) fuel cells are regarded as highly promising energy conversion systems for future transportation and stationary power generation and have been under intensive investigations for the last decade. Unfortunately, cutting edge PEM fuel cell design and components still do not allow economically commercial implementation of this technology. The main obstacles are high cost of proton conductive membranes, low-proton conductivity at low relative humidity (RH), and dehydration and degradation of polymer membranes at high temperatures. The objective of this study was to develop a systematic approach to design a high proton conductive composite membrane that can provide a conductivity of approximately 100 mS cm-1 under hot and dry conditions (120°C and 50% RH). The approach was based on fundamental and experimental studies of the proton conductivity of inorganic additives and composite membranes. We synthesized and investigated a variety of organic-inorganic Nafion-based composite membranes. In particular, we analyzed their fundamental properties, which included thermal stability, morphology, the interaction between inorganic network and Nafion clusters, and the effect of inorganic phase on the membrane conductivity. A wide range of inorganic materials was studied in advance in order to select the proton conductive inorganic additives for composite membranes. We developed a conductivity measurement method, with which the proton conductivity characteristics of solid acid materials, zirconium phosphates, sulfated zirconia (S-ZrO2), phosphosilicate gels, and Santa Barbara Amorphous silica (SBA-15) were discussed in detail. Composite membranes containing Nafion and different amounts of functionalized inorganic additives (sulfated inorganics such as S-ZrO2, SBA-15, Mobil Composition of Matter MCM-41, and S-SiO2, and phosphonated inorganic P-SiO2) were synthesized with different methods. We incorporated inorganic particles within Nafion clusters either by mixing inorganic gels or solutions with Nafion solution followed by membrane casting or by blending inorganic powders with Nafion solution. The membrane properties, such as acidity, swelling, water uptake, thermostability, proton conductivity, and electrochemical performance, were explored in depth. We characterized the inorganic phase inside composite membranes and its interaction with the Nafion matrix by scanning electron microscopy (SEM) and Fourier transform infrared spectroscopy (FT-IR). Furthermore, we discussed the effect of these inorganic conductors' properties, such as particle size, conductivity, and interaction between functional groups and the Nafion, on the membrane conductivity. The contribution of hydrophilic inorganic particles in improving the membrane fuel cell performance was numerically analyzed by Tafel plot. Finally, the proton conductivity phenomena in composite membranes were simulated with two proton-transport models; one was based on the rule of mixtures, and the other was described by generalized Stefan-Maxwell equations. In the simulation, we proposed a new route in rational design of high proton-conductive composite membranes.

  5. Laser desorption ionization mass spectrometry of peptides on a hybrid CHCA organic-inorganic matrix.

    PubMed

    Fleith, Clément; Cantel, Sonia; Subra, Gilles; Mehdi, Ahmad; Ciccione, Jeremie; Martinez, Jean; Enjalbal, Christine

    2014-08-01

    We report applications of new hybrid organic-inorganic silica based materials as laser desorption/ionization (LDI)-promoting surfaces for high-throughput identification of peptides. The driving force of our work was to design a new material composed of a conventional MALDI matrix covalently attached to silica with a high organic/inorganic ratio in order to improve the UV absorption by such LDI hybrid matrices. Amorphous CHCA-functionalized silica presenting an organic content up to 1.3 mmol g(-1) (around 40% in weight from TGA and elementary analysis measurements) gave very interesting LDI performances in terms of detection sensitivity as well as relative ionization discrepancy (spectral suppression) through the analyses of small synthetic peptide mixtures (550-1300 Da) taking CHCA and amorphous silica as model matrices for control experiments. PMID:24910856

  6. Functionally Graded Designer Viscoelastic Materials Tailored to Perform Prescribed Tasks with Probabilistic Failures and Lifetimes

    SciTech Connect

    Hilton, Harry H.

    2008-02-15

    Protocols are developed for formulating optimal viscoelastic designer functionally graded materials tailored to best respond to prescribed loading and boundary conditions. In essence, an inverse approach is adopted where material properties instead of structures per se are designed and then distributed throughout structural elements. The final measure of viscoelastic material efficacy is expressed in terms of failure probabilities vs. survival time000.

  7. A Review of Organic and Inorganic Biomaterials for Neural Interfaces

    PubMed Central

    Fattahi, Pouria; Yang, Guang; Kim, Gloria

    2015-01-01

    Recent advances in nanotechnology have generated wide interest in applying nanomaterials for neural prostheses. An ideal neural interface should create seamless integration into the nervous system and performs reliably for long periods of time. As a result, many nanoscale materials not originally developed for neural interfaces become attractive candidates to detect neural signals and stimulate neurons. In this comprehensive review, an overview of state-of-the-art microelectrode technologies provided first, with focus on the material properties of these microdevices. The advancements in electro active nanomaterials are then reviewed, including conducting polymers, carbon nanotubes, graphene, silicon nanowires, and hybrid organic-inorganic nanomaterials, for neural recording, stimulation, and growth. Finally, technical and scientific challenges are discussed regarding biocompatibility, mechanical mismatch, and electrical properties faced by these nanomaterials for the development of long-lasting functional neural interfaces. PMID:24677434

  8. Functionalization of layered titanates.

    PubMed

    Ide, Yusuke; Sadakane, Masahiro; Sano, Tsuneji; Ogawa, Makoto

    2014-03-01

    This review article describes the synthesis, modification, and function of lepidocrocite-type layered titanate (A(x)Ti(2-y)M(y)O4, A: A, interlayer cation; M, metal or vacancy). Due to the compositional variation, which affects cation exchange, semiconducting and swelling properties, lepidocrocite-type layered titanates have attracted increasing attention in solid-state materials chemistry. The immobilization of functional units has been done to improve the properties as well as to impart additional functions. Here, we highlight recent developments of hybrid materials derived from the intercalation of inorganic and organic cations, organic functional groups, and nanoparticles into lepidocrocite-type layered titanates. PMID:24745207

  9. Functionally Graded Piezoelectric Material Systems A Multiphysics Perspective

    E-print Network

    Paulino, Glaucio H.

    , a material made using the FGM concept would maintain some of the advantages of traditional composites to design FGM composites: macro- and microscale approach. In macroscale approach, the conventional.3, the concept of FGM is introduced. In Section 8.4, the formulation of the finite element method (FEM

  10. Functional materials analysis using in situ and in operando X-ray and neutron scattering

    PubMed Central

    Peterson, Vanessa K.; Papadakis, Christine M.

    2015-01-01

    In situ and in operando studies are commonplace and necessary in functional materials research. This review highlights recent developments in the analysis of functional materials using state-of-the-art in situ and in operando X-ray and neutron scattering and analysis. Examples are given covering a number of important materials areas, alongside a description of the types of information that can be obtained and the experimental setups used to acquire them. PMID:25866665

  11. Ultralow thermal conductivity of atomic/molecular layer-deposited hybrid organic-inorganic zincone thin films.

    PubMed

    Liu, Jun; Yoon, Byunghoon; Kuhlmann, Eli; Tian, Miao; Zhu, Jie; George, Steven M; Lee, Yung-Cheng; Yang, Ronggui

    2013-01-01

    Atomic layer deposition (ALD) and molecular layer deposition (MLD) techniques with atomic level control enable a new class of hybrid organic-inorganic materials with improved functionality. In this work, the cross-plane thermal conductivity and volumetric heat capacity of three types of hybrid organic-inorganic zincone thin films enabled by MLD processes and alternate ALD-MLD processes were measured using the frequency-dependent time-domain thermoreflectance method. We revealed the critical role of backbone flexibility in the structural morphology and thermal conductivity of MLD zincone thin films by comparing the thermal conductivity of MLD zincone films with an aliphatic backbone to that with aromatic backbone. Much lower thermal conductivity values were obtained in ALD/MLD-enabled hybrid organic-inorganic zincone thin films compared to that of the ALD-enabled W/Al2O3 nanolaminates reported by Costescu et al. [Science 2004, 303, 989-990], which suggests that the dramatic material difference between organic and inorganic materials may provide a route for producing materials with ultralow thermal conductivity. PMID:24164650

  12. Ionic liquids for soft functional materials with carbon nanotubes.

    PubMed

    Fukushima, Takanori; Aida, Takuzo

    2007-01-01

    A serendipitous finding that ionic liquids gel with carbon nanotubes has opened a new possibility of ionic liquids as modifiers for carbon nanotubes. Upon being ground into ionic liquids, carbon nanotube bundles are untangled, and the resultant fine bundles form a network structure. This is due to the possible specific interaction between the imidazolium ion component and the pi-electronic nanotube surface. The resultant gelatinous materials, consisting of highly electroconductive nanowires and fluid electrolytes, can be utilized for a wide variety of electrochemical applications, such as sensors, capacitors, and actuators. Ionic liquids allow for noncovalent and covalent modifications of carbon nanotubes and fabrication of polymer composites with enhanced physical properties. The processing of carbon nanotubes with ionic liquids is not accompanied by the disruption of the pi-conjugated nanotube structure and does not require solvents; therefore it can readily be scaled up. This article focuses on new aspects of ionic liquids for designer soft materials based on carbon nanotubes. PMID:17516613

  13. Enhanced Functionality for Materials Analysis in the DTEM

    SciTech Connect

    Nigel D. Browning

    2008-04-28

    The recent explosion in the use of pump–probe studies on the picosecond timescale to investigate structural and electronic phase transitions and the dynamics of chemical reactions has been based largely on laser–induced reactions coupled with laser interrogation techniques, or on laser induced reactions coupled with synchrotron radiation interrogation techniques. Much less attention has been given to approaches based on laser–induced (or electron–beam–induced) reactions coupled with electron interrogation methods, despite the fact that electron sources are brighter, and their interactions with matter stronger (thereby giving higher signal levels). The use of electrons as probes has great potential to study complex transient events not only because of the possible high temporal resolution using ultrafast electron diffraction (UED) but also the potential for high spatial resolution using dynamic transmission electron microscopy (DTEM). Taking this potential of electron interrogation methods and turning it into a routine nanoscale characterization technique requires several key aspects of the instrumentation used for electron microscopy/diffraction to be optimized. In this proposal, several approaches to instrument optimization for DTEM and UED (to be performed in the same instrument) will be addressed. The new instrumentation developments will be used to study the dynamics of strongly driven materials, aging and corrosion in structural materials, as well as the nanoscale structural properties of other materials systems. In addition to providing new instrument capabilities (the technology for which will be transferred to the DTEM at Lawrence Livermore National Laboratory (LLNL)) and fundamental insights into the dynamic properties of materials, the interaction between 3 universities (University of California-Davis, University of Illinois at Chicago and Arizona State University) and 2 national laboratories (LLNL and Sandia National Laboratory) will help train the next generation of students in areas of relevance to the stockpile stewardship.

  14. Dsign of Inorganic Electrides

    NASA Astrophysics Data System (ADS)

    Yunwei, Zhang; Feng, Peng; Yanming, Ma

    Electrides, in which all of or part of the valence electrons occupy interstitial regions in the crystal and behave as anions, have been synthesized at ambient or high-pressure conditions. Their loosely bound anionic electrons make electrides good candidates for electro-active materials. Here, we report a developed methodology to systematically design electrides for given chemical systems. The new approach is based on the swarm-intelligence CALYPSO algorithm on structure prediction and requires only the chemical compositions to predict the electride phases. In contrast to the traditional ground state structure prediction method where the total energy was solely used as the fitness function, we adopted a new fitness function in combination with the first-principles calculation to select the optimal solutions for a description of given chemical systems. The result suggested that our approach is reliable and can be widely applied into design of new electrides.

  15. Design of Inorganic Electrides

    NASA Astrophysics Data System (ADS)

    Zhang, Yunwei; Wang, Hui; Wang, Yanchao; Ma, Yanming

    2015-03-01

    Electrides, in which all of or part of the valence electrons occupy interstitial regions in the crystal and behave as anions, have been synthesized at ambient or high-pressure conditions. Their loosely bound anionic electrons make electrides good candidates for electro-active materials. Here, we report a developed methodology to systematically design electrides for given chemical systems. The new approach is based on the swarm-intelligence CALYPSO algorithm on structure prediction and requires only the chemical compositions to predict the electride phases. In contrast to the traditional ground state structure prediction method where the total energy was solely used as the fitness function, we adopted a new fitness function in combination with the first-principles calculation to select the optimal solutions for a description of given chemical systems. The experimentally know electrides have been successfully reproduced. The results suggested that our approach is reliable and can be widely applied into design of new electrides.

  16. Materials Design and Discovery with High-Throughput Density Functional Theory: The Open Quantum Materials Database (OQMD)

    NASA Astrophysics Data System (ADS)

    Saal, James E.; Kirklin, Scott; Aykol, Muratahan; Meredig, Bryce; Wolverton, C.

    2013-11-01

    High-throughput density functional theory (HT DFT) is fast becoming a powerful tool for accelerating materials design and discovery by the amassing tens and even hundreds of thousands of DFT calculations in large databases. Complex materials problems can be approached much more efficiently and broadly through the sheer quantity of structures and chemistries available in such databases. Our HT DFT database, the Open Quantum Materials Database (OQMD), contains over 200,000 DFT calculated crystal structures and will be freely available for public use at http://oqmd.org. In this review, we describe the OQMD and its use in five materials problems, spanning a wide range of applications and materials types: (I) Li-air battery combination catalyst/electrodes, (II) Li-ion battery anodes, (III) Li-ion battery cathode coatings reactive with HF, (IV) Mg-alloy long-period stacking ordered (LPSO) strengthening precipitates, and (V) training a machine learning model to predict new stable ternary compounds.

  17. Supported inorganic membranes

    DOEpatents

    Sehgal, Rakesh (Albuquerque, NM); Brinker, Charles Jeffrey (Albuquerque, NM)

    1998-01-01

    Supported inorganic membranes capable of molecular sieving, and methods for their production, are provided. The subject membranes exhibit high flux and high selectivity. The subject membranes are substantially defect free and less than about 100 nm thick. The pores of the subject membranes have an average critical pore radius of less than about 5 .ANG., and have a narrow pore size distribution. The subject membranes are prepared by coating a porous substrate with a polymeric sol, preferably under conditions of low relative pressure of the liquid constituents of the sol. The coated substrate is dried and calcined to produce the subject supported membrane. Also provided are methods of derivatizing the surface of supported inorganic membranes with metal alkoxides. The subject membranes find use in a variety of applications, such as the separation of constituents of gaseous streams, as catalysts and catalyst supports, and the like.

  18. Recovery of properties of a material from the transfer function of the bulk sample (theory)

    E-print Network

    Kouznetsov, Dmitrii

    Recovery of properties of a material from the transfer function of the bulk sample (theory) Dmitrii should be used (to extract from the mea- surements only the parameters of the model), or the sample of the transfer function of the bulk sample is suggested as an alternative. The transfer function of a sample

  19. Development of Ti/Ti{sub 3}Sn functionally gradient material produced by eutectic bonding method

    SciTech Connect

    Kirihara, S.; Takeda, M.; Tsujimoto, T.

    1996-07-15

    Although many materials which have a single function have been developed, future needs are anticipated to include materials which have various functions. A functionally gradient material (FGM) which has characteristics of two different materials is a promising candidate for multi-functional material. The present methods for production of FGM, however, are very complicated and costly. In this study the authors answer the serious problem of high production cost by fabricating the FGM by a eutectic bonding method. This fabrication method includes structural control of FGM by changing the cooling process. They describe Ti/Ti{sub 3}Sn FGM obtained by the eutectic bonding method, and tell how the structure of its composition gradient part is changed by controlling the cooling process.

  20. Application of Patterson-function direct methods to materials characterization

    PubMed Central

    Rius, Jordi

    2014-01-01

    The aim of this article is a general description of the so-called Patterson-function direct methods (PFDM), from their origin to their present state. It covers a 20-year period of methodological contributions to crystal structure solution, most of them published in Acta Crystallographica Section A. The common feature of these variants of direct methods is the introduction of the experimental intensities in the form of the Fourier coefficients of origin-free Patterson-type functions, which allows the active use of both strong and weak reflections. The different optimization algorithms are discussed and their performances compared. This review focuses not only on those PFDM applications related to powder diffraction data but also on some recent results obtained with electron diffraction tomography data. PMID:25295171

  1. A model for designing functionally gradient material joints

    SciTech Connect

    Jou, M.; Messler, R.W.; Orling, T.T.

    1994-12-31

    Joining of dissimilar materials into hybrid structures to meet severe design and service requirements is becoming more necessary and common. Joints between heat-resisting or refractory metals and refractory or corrosion resistant ceramics and intermetallics are especially in demand. Before resorting to a more complicated but versatile finite element analysis (FEA) model, a simpler, more user-friendly analytical layer-model based on a thin plate assumption was developed and tested. The model has been successfully used to design simple FGM joints between Ni-base superalloys or Mo and SiC, Ni{sub 3}Al or Al{sub 2}O{sub 3} using self-propagating high-temperature or pressurized composition synthesis for joining. Cases are presented to demonstrate capability for: (1) varying processing temperature excursions or service gradients; (2) varying overall joint thickness for a fixed number of uniform composition steps; (3) varying the number of uniform steps for a particular overall joint thickness; (4) varying the thickness and/or composition of individual steps for a constant overall thickness; and (5) altering the constitutive law for mixed-material composition steps. The model provides a useful joint design tool for process R&D.

  2. Transmission electron microscopy for archaeo-materials research: Nanoparticles in glazes and red/yellow glass and inorganic pigments in painted context

    NASA Astrophysics Data System (ADS)

    Fredrickx, Peggy

    2004-10-01

    This dissertation addresses the application of Transmission Electron Microscopy (TEM) to historic objects, concentrating on colour-causing nanoparticles in vitreous materials and pigments with the focus on substrates in lake pigments used in thin glaze layers, and on manuscript illustrations. TEM is well suited for archaeometry: it gives chemical elemental information, imaging and diffraction information and the amount of material needed is minimal. Sample preparation techniques suitable for historic materials are discussed. Nanoparticles can be incorporated in glass through staining. Yellow coloured glass plates contain Ag particles. Baking temperatures and different Ag-salts determine the density of the nanoparticles. Dense layers cause more saturated colours. Red glass plates can be obtained by staining with Cu-salts. Metallic Cu particles have a diameter of about 24 nm. Comparison with XRF results suggests that often a combination of Cu and Ag was used for warmer colours. Red glass can be "flashed" to the substrate glass. Then, the colour is also caused by metallic Cu particles. The red layer often displays a band structure of stacked red and transparent bands. In the transparent bands, no nanoparticles have been found. In lustre-ware, Ag and metallic Cu occur. Their distribution throughout the material determines the colour of the fragment. In both there is a dense top layer with particles of sizes smaller than 15 nm. If this top layer consists of Ag particles, the resulting colour is golden. In one sample, under this top layer the amount of Cu particles increases. This underlying layer causes the colour to redden. Particles are mainly between 5 and 15 nm in diameter. Using reconstructions, it has been demonstrated that TEM can detect and identify a stacking of thin layers in parchment decorations. A pink powder sample from Pompeii consists of a basis of allophane type clay. The lake substrates consist of Al, O, S and their amorphous structure does not seem to be noticeably changed by the addition of organic colourants. Hydrocerussite crystals (i.e. the main component of lead white) have been added to some historic glaze layers. Further it was confirmed that sometimes crystalline CaSO4 particles were added to lakes.

  3. Functional requirements document for measuring emissions of airborne radioactive materials

    SciTech Connect

    Criddle, J.D. Jr.

    1994-09-01

    This document states the functional requirements and procedures for systems making measurements of radioactive airborne emissions from facilities at the Hanford Site. The following issues are addressed in this document: Definition of the program objectives; Selection of the overall approach to collecting the samples; Sampling equipment design; Sampling equipment maintenance, and quality assurance issues. The intent of this document is to assist WHC in demonstrating a high quality of air emission measurements with verified system performance based on documented system design, testing, inspection, and maintenance.

  4. Biomedical Probes Based on Inorganic Nanoparticles for Electrochemical and Optical Spectroscopy Applications

    PubMed Central

    Yakoh, Abdulhadee; Pinyorospathum, Chanika; Siangproh, Weena; Chailapakul, Orawon

    2015-01-01

    Inorganic nanoparticles usually provide novel and unique physical properties as their size approaches nanometer scale dimensions. The unique physical and optical properties of nanoparticles may lead to applications in a variety of areas, including biomedical detection. Therefore, current research is now increasingly focused on the use of the high surface-to-volume ratios of nanoparticles to fabricate superb chemical- or biosensors for various detection applications. This article highlights various kinds of inorganic nanoparticles, including metal nanoparticles, magnetic nanoparticles, nanocomposites, and semiconductor nanoparticles that can be perceived as useful materials for biomedical probes and points to the outstanding results arising from their use in such probes. The progress in the use of inorganic nanoparticle-based electrochemical, colorimetric and spectrophotometric detection in recent applications, especially bioanalysis, and the main functions of inorganic nanoparticles in detection are reviewed. The article begins with a conceptual discussion of nanoparticles according to types, followed by numerous applications to analytes including biomolecules, disease markers, and pharmaceutical substances. Most of the references cited herein, dating from 2010 to 2015, generally mention one or more of the following characteristics: a low detection limit, good signal amplification and simultaneous detection capabilities. PMID:26343676

  5. Work function determination of promising electrode materials for thermionic converters

    NASA Technical Reports Server (NTRS)

    Jacobson, D.

    1977-01-01

    Work performed on this contract was primarily for the evaluation of selected electrode materials for thermionic energy converters. The original objective was to characterize selected nickel based superalloys up to temperatures of 1400 K. It was found that an early selection, Inconel 800 produced a high vapor pressure which interfered with the vacuum emission measurements. The program then shifted to two other areas. The first area was to obtain emission from the superalloys in a cesiated atmosphere. The cesium plasma helps to suppress the vaporization interference. The second area involved characterization of the Lanthanum-Boron series as thermionic emitters. These final two areas resulted in three journal publications which are attached to this report.

  6. [Physiopathology of inorganic lead poisoning].

    PubMed

    Kaminsky, P; Klein, M; Duc, M

    1993-03-01

    This paper gives an overview of the hypotheses concerning the mechanisms of inorganic lead toxicity on cells and tissues, with emphasis on the effect of low-concentration lead. Inhibition of heme synthesis is responsible not only for lead-induced anaemia, but also for accumulation of delta-aminolaevulinic acid (ALA) and for lowering the concentration of cytochromes contained in the mitochondrial respiratory chain. Auto-oxidation of ALA is thought to result in the formation of free radicals. On the other hand, lead replaces ionic calcium in its role as second cell messenger. This mechanism would explain the abnormalities observed in synaptic transmission, arteriolar vasoreactivity and functioning of such cells as osteoclasts and osteoblasts. Nuclear toxicity, with abnormal expression of DNA genes and inhibition of certain enzymes such as membrane Na+/K+ ATPase, are also considered. The mechanisms of tissue toxicity are discussed. PMID:8378637

  7. Natural material adsorbed onto a polymer to enhance immune function

    PubMed Central

    Reinaque, Ana Paula Barcelos; França, Eduardo Luzía; Scherer, Edson Fredulin; Côrtes, Mayra Aparecida; Souto, Francisco José Dutra; Honorio-França, Adenilda Cristina

    2012-01-01

    Background In this study, we produced poly(ethylene glycol) (PEG) microspheres of different sizes and adsorbing a medicinal plant mixture, and verified their effect in vitro on the viability, superoxide production, and bactericidal activity of phagocytes in the blood. Methods The medicinal plant mixture was adsorbed onto PEG microspheres and its effects were evaluated by flow cytometry and fluorescence microscopy. Results Adsorption of the herbal mixture onto the PEG microspheres was achieved and the particles were internalized by phagocytes. PEG microspheres bearing the adsorbed herbal mixture stimulated superoxide release, and activated scavenging and microbicidal activity in phagocytes. No differences in functional activity were observed when the phagocytes were not incubated with PEG microspheres bearing the adsorbed herbal mixture. Conclusion This system may be useful for the delivery of a variety of medicinal plants and can confer additional protection against infection. The data reported here suggest that a polymer adsorbed with a natural product is a treatment alternative for enhancing immune function. PMID:22956861

  8. The quest for inorganic fullerenes

    NASA Astrophysics Data System (ADS)

    Pietsch, Susanne; Dollinger, Andreas; Strobel, Christoph H.; Park, Eun Ji; Ganteför, Gerd; Seo, Hyun Ook; Kim, Young Dok; Idrobo, Juan-Carlos; Pennycook, Stephen J.

    2015-10-01

    Experimental results of the search for inorganic fullerenes are presented. MonSm- and WnSm- clusters are generated with a pulsed arc cluster ion source equipped with an annealing stage. This is known to enhance fullerene formation in the case of carbon. Analogous to carbon, the mass spectra of the metal chalcogenide clusters produced in this way exhibit a bimodal structure. The species in the first maximum at low mass are known to be platelets. Here, the structure of the species in the second maximum is studied by anion photoelectron spectroscopy, scanning transmission electron microscopy, and scanning tunneling microcopy. All experimental results indicate a two-dimensional structure of these species and disagree with a three-dimensional fullerene-like geometry. A possible explanation for this preference of two-dimensional structures is the ability of a two-element material to saturate the dangling bonds at the edges of a platelet by excess atoms of one element. A platelet consisting of a single element only cannot do this. Accordingly, graphite and boron might be the only materials forming nano-spheres because they are the only single element materials assuming two-dimensional structures.

  9. PREFACE: 3rd International Symposium on Functional Materials 2009 (ISFM 2009) 3rd International Symposium on Functional Materials 2009 (ISFM 2009)

    NASA Astrophysics Data System (ADS)

    Kiwon, Kim; Li, Lu; Taehyun, Nam; Jouhyeon, Ahn

    2010-05-01

    The 3rd International Symposium on Functional Materials 2009 (ISFM 2009) and its preconference, Advances in Functional Materials 2009 (AFM 2009), were successfully held in the Republic of Korea from 15-18 June 2009 and in the People's Republic of China from 8-12 June 2009, respectively. The two conferences attracted over 300 oral and poster presentations from over 12 countries including Australia, Canada, China, Germany, Japan, India, Israel, Korea, The Netherlands, Thailand, the UK and the USA. In the two conferences, eight keynote lectures were delivered by S Miyazaki, S A Akbar, D J Singh, C Suryanarayana, M~Greenblatt, H Zhang, T Sato and J Ding. This topical issue of Physica Scripta contains papers presented at the ISFM 2009 and AFM 2009. Keyan Li from Dalian University, People's Republic of China, presents some empirical formulae to estimate the elastic moduli of rocksalt-, zincblende- and chalcopyrite-structured crystals, on the basis of electronegativities of bonded atoms in the crystallographic frame. Min-Jung Kim from Hanyang University, Korea, reports on the preparation and characterization of carboxyl functionalization of magnetite nanoparticles for oligonucleotide immobilization. F Yan from the National University of Singapore studies the fabrication of Bi(Fe0.5Sc0.5)O3-PbTiO3 (BSF-PT) thin films by pulsed laser deposition, and the enhanced magnetic moment with respect to BiFeO3-PbTiO3. Dong-Gil Lee from Pusan National University, Korea, reports on the sterilization of enteropathogenic Escherichia coli using nanofiber TiO2 films prepared by the electrostatic spray method. Sang-Eun Park from the Korea Institute of Science and Technology reports on the study of encapsulated Fe3O4 nanoparticles with a silica thin layer with a reversible capacity of about 363 mAhg-1. Other researchers report on many other exiting achievements in the fields of ferromagnetic materials, magneto-optical materials, thermoelectric materials, shape memory materials, fuel-cell and battery materials, and other related advanced functional materials. The 4th International Symposium on Functional Materials 2011 (ISFM 2011) will be held in Sendai, Japan, from 2-6 August 2011 just before the Sendai Tanabata Festival. Its preconference (AFM 2011) will be held at Jeju Island, Korea, just before ISFM 2011. We look forward to meeting you in Jeju and Sendai.

  10. Analytical electron microscopy of biogenic and inorganic carbonates

    NASA Technical Reports Server (NTRS)

    Blake, David F.

    1989-01-01

    In the terrestrial sedimentary environment, the mineralogically predominant carbonates are calcite-type minerals (rhombohedral carbonates) and aragonite-type minerals (orthorhombic carbonates). Most common minerals precipitating either inorganically or biogenically are high magnesium calcite and aragonite. High magnesium calcite (with magnesium carbonate substituting for more than 7 mole percent of the calcium carbonate) is stable only at temperatures greater than 700 C or thereabouts, and aragonite is stable only at pressures exceeding several kilobars of confining pressure. Therefore, these carbonates are expected to undergo chemical stabilization in the diagenetic environment to ultimately form stable calcite and dolomite. Because of the strong organic control of carbonate deposition in organisms during biomineralization, the microchemistry and microstructure of invertebrate skeletal material is much different than that present in inorganic carbonate cements. The style of preservation of microstructural features in skeletal material is therefore often quite distinctive when compared to that of inorganic carbonate even though wholesale recrystallization of the sediment has taken place. Microstructural and microchemical comparisons are made between high magnesium calcite echinoderm skeletal material and modern inorganic high magnesium calcite inorganic cements, using analytical electron microscopy and related techniques. Similar comparisons are made between analogous materials which have undergone stabilization in the diagenetic environment. Similar analysis schemes may prove useful in distinguishing between biogenic and inorganic carbonates in returned Martian carbonate samples.

  11. Inorganic rechargeable non-aqueous cell

    DOEpatents

    Bowden, William L. (Nashua, NH); Dey, Arabinda N. (Needham, MA)

    1985-05-07

    A totally inorganic non-aqueous rechargeable cell having an alkali or alkaline earth metal anode such as of lithium, a sulfur dioxide containing electrolyte and a discharging metal halide cathode, such as of CuCl.sub.2, CuBr.sub.2 and the like with said metal halide being substantially totally insoluble in SO.sub.2 and admixed with a conductive carbon material.

  12. Sol-gel processing with inorganic metal salt precursors

    DOEpatents

    Hu, Zhong-Cheng

    2004-10-19

    Methods for sol-gel processing that generally involve mixing together an inorganic metal salt, water, and a water miscible alcohol or other organic solvent, at room temperature with a macromolecular dispersant material, such as hydroxypropyl cellulose (HPC) added. The resulting homogenous solution is incubated at a desired temperature and time to result in a desired product. The methods enable production of high quality sols and gels at lower temperatures than standard methods. The methods enable production of nanosize sols from inorganic metal salts. The methods offer sol-gel processing from inorganic metal salts.

  13. Analysis of smart functionally graded materials using an improved third order shear deformation theory 

    E-print Network

    Aliaga Salazar, James Wilson

    2009-06-02

    Smart materials are very important because of their potential applications in the biomedical, petroleum and aerospace industries. They can be used to build systems and structures that self-monitor to function and adapt to ...

  14. A Review on the Finite Element Methods for Heat Conduction in Functionally Graded Materials

    NASA Astrophysics Data System (ADS)

    Sharma, R.; Jadon, V. K.; Singh, B.

    2015-01-01

    The review presented in this paper focuses mainly on the application of finite element methods for investigating the effect of heat transfer, variation of temperature and other parameters in the functionally graded materials. Different methods have been investigated for thermal conduction in functionally graded materials. The use of FEM for steady state heat transfer has been addressed in this work. The authors have also discussed the utilization of FEM based shear deformation theories and FEM in combination with other methods for the problems involving complexity of the shape and geometry of functionally graded materials. Finite element methods proved to be effective for the solution of heat transfer problem in functionally graded materials. These methods can be used for steady state heat transfer and as well as for transient state.

  15. Differential adhesion of amino acids to inorganic surfaces.

    PubMed

    Willett, R L; Baldwin, K W; West, K W; Pfeiffer, L N

    2005-05-31

    A fundamental, yet underexplored, materials system is the interface between biological molecules and inorganic surfaces. In an elemental approach to this problem, we have systematically examined the adhesion of amino acids to a series of inorganic surfaces including metals, insulators, and semiconductors. Significant differential adhesion is observed over the full complement of amino acids, determined largely by amino acid side-chain charge. Extensive mapping of the amino acid adhesion versus materials in multiple solutions is presented, with preliminary mechanisms derived from concentration and pH dependence. These results provide an empirical basis for building peptide to inorganic surface structures, and, using this adhesion data, we design inorganic nanostructures that are shown to selectively bind to prescribed primary peptide sequences. PMID:15901900

  16. Electrochemical determination of inorganic mercury and arsenic--A review.

    PubMed

    Zaib, Maria; Athar, Muhammad Makshoof; Saeed, Asma; Farooq, Umar

    2015-12-15

    Inorganic mercury and arsenic encompasses a term which includes As(III), As(V) and Hg(II) species. These metal ions have been extensively studied due to their toxicity related issues. Different analytical methods are used to monitor inorganic mercury and arsenic in a variety of samples at trace level. The present study reviews various analytical techniques available for detection of inorganic mercury and arsenic with particular emphasis on electrochemical methods especially stripping voltammetry. A detailed critical evaluation of methods, advantages of electrochemical methods over other analytical methods, and various electrode materials available for mercury and arsenic analysis is presented in this review study. Modified carbon paste electrode provides better determination due to better deposition with linear and improved response under studied set of conditions. Biological materials may be the potent and economical alternative as compared to macro-electrodes and chemically modified carbon paste electrodes in stripping analysis of inorganic mercury and arsenic. PMID:26253796

  17. Early Transition Metal Oxides as Catalysts: Crossing Scales from Clusters to Single Crystals to Functioning Materials

    SciTech Connect

    Lai-Sheng Wang

    2009-07-07

    The overall goal of this program is to investigate the electronic structure and chemical bonding of early transition metal oxide clusters and use them as well-defined molecular models to obtain insight into properties and mechanisms of oxide catalysts, as well as to provide accurate spectroscopic and molecular information to verify theoretical methods used to predict materials properties. A laser vaporization cluster source is used to produce metal oxide clusters with different sizes, structures, and compositions. Well-defined inorganic polyoxometalate clusters in solution are transported in the gas phase using electrospray. Two state-of-the-art photoelectron spectroscopy apparatuses are used to interrogate the oxide clusters and polyoxometalate anions in the gas phase to obtain spectroscopic and electronic structure information. The experimental effort is assisted by theoretical calculations to understanding the structures, chemical bonding, and catalytical properties of the transition metal oxide clusters. The research approach combines novel and flexible experimental techniques and advanced theoretical/computational methodologies and seeks molecular-level information to aiding the design of new catalysts, as well as mechanistic understanding. We have focused on the investigation of tungsten oxide clusters containing three W atoms: W{sub 3}O{sub x}{sup -} (x = 7-11). A number of interesting findings have been made. We observed that the oxygen-poor W{sub 3}O8 cluster contains a localized W{sup 4+} center, which can be used as a molecular model for O-deficient defect sites. A chemisorption energy was obtained through density functional calculations for W{sub 3}O8 + O{sub 2} {yields} W{sub 3}O{sub 10} as -78 kcal/mol. We further found that the neutral stoichiometric W{sub 2}O{sub 6} and W{sub 3}O{sub 9} clusters do not react with O{sub 2} and they only form physi-sorbed complexes, W{sub 2}O{sub 6}(O{sub 2}) and W{sub 3}O{sub 9}(O{sub 2}). However, the negatively charged W{sub 2}O{sub 6}{sup -} and W{sub 3}O{sub 9}{sup -} clusters are found to form chemisorbed complexes due to the presence of the extra electron. Thus, the W{sub 2}O{sub 6}{sup -} and W{sub 3}O{sub 9}{sup -} negative clusters can be viewed as models for O{sub 2} interaction with a reduced W site (W{sup 5+}) on the oxide surface. These studies also led to the surprising observation of the first d-orbital aromatic clusters in W{sub 3}O{sub 9}{sup 2-} and Mo{sub 3}O{sub 9}{sup 2-}, which each contains a completely delocalized three-center two-electron bond made entirely made of the metal d orbitals. This last result was highlighted in both Chem & Eng. News and Nature. We further studied a series of small metalate anions using electrospray, including the hydroxo and methoxo oxometalate MO{sub 3}(OH){sup -} and MO{sub 3}(OCH{sub 3}){sup -}, and the dimetalates: M{sub 2}O{sub 7}{sup 2-}, MM{prime}O{sub 7}{sup 2-}, and M{sub 2}O{sub 7}{sup -} (M, M{prime} = Cr, Mo, and W).

  18. Successful transfer of plasmid DNA into in vitro cells transfected with an inorganic plasmid-Mg/Al-LDH nanobiocomposite material as a vector for gene expression

    NASA Astrophysics Data System (ADS)

    Jaffri Masarudin, Mas; Yusoff, Khatijah; Rahim, Raha Abdul; Zobir Hussein, Mohd

    2009-01-01

    The delivery of a full plasmid, encoding the green fluorescent protein gene into African monkey kidney (Vero3) cells, was successfully achieved using nanobiocomposites based on layered double hydroxides. This demonstrated the potential of using the system as an alternative DNA delivery vector. Intercalation of the circular plasmid DNA, pEGFP-N2, into Mg/Al-NO3- layered double hydroxides (LDH) was accomplished through anion exchange routes to form the nanobiocomposite material. The host was previously synthesized at the Mg2+ to Al3+ molar ratio Ri = 2 and subsequently intercalated with plasmid DNA. Size expansion of the interlamellae host from 8.8 Å in LDH to 42 Å was observed in the resulting nanobiocomposite, indicating stable hybridization of the plasmid DNA. The powder x-ray diffraction (PXRD) results, supplemented with Fourier-transform infrared (FTIR) spectroscopy, compositional and electrophoresis studies confirmed the encapsulation episode of the biomaterial. In order to elucidate the use of this resulting nanobiocomposite as a delivery vector, an MTT assay was performed to determine any cytotoxic effects of the host towards cells. The intercalated pEGFP-N2 anion was later successfully recovered through acidification with HNO3 after treatment with DNA-degrading enzymes, thus also showing the ability of the LDH host to protect the intercalated biomaterial from degradation. Cell transfection studies on Vero3 cells were then performed, where cells transfected with the nanobiocomposite exhibited fluorescence as early as 12 h post-treatment compared to naked delivery of the plasmid itself.

  19. Compositions, Functions, and Testing of Friction Brake Materials and Their Additives

    SciTech Connect

    Blau, PJ

    2001-10-22

    The purpose of this report is to present a survey of commercial brake materials and additives, and to indicate their typical properties and functions, especially as regards their use in heavy trucks. Most truck pad and shoe materials described here were designed to wear against cast iron. Brake material test methods are also briefly described. This report does not address issues associated with the fabrication and manufacturing of brake materials. Since there are literally thousands of brake material additives, and their combinations are nearly limitless, it is impractical to list them all here. Rather, an attempt has been made to capture the primary constituents and their functions. An Appendix contains thermo-physical properties of some current and potential brake materials.

  20. Inorganic: the other mercury.

    PubMed

    Risher, John F; De Rosa, Christopher T

    2007-11-01

    There is a broad array of mercury species to which humans may be exposed. While exposure to methylmercury through fish consumption is widely recognized, the public is less aware of the sources and potential toxicity of inorganic forms of mercury. Some oral and laboratory thermometers, barometers, small batteries, thermostats, gas pressure regulators, light switches, dental amalgam fillings, cosmetic products, medications, cultural/religious practices, and gold mining all represent potential sources of exposure to inorganic forms of mercury. The route of exposure, the extent of absorption, the pharmacokinetics, and the effects all vary with the specific form of mercury and the magnitude and duration of exposure. If exposure is suspected, a number of tissue analyses can be conducted to confirm exposure or to determine whether an exposure might reasonably be expected to be biologically significant. By contrast with determination of exposure to methylmercury, for which hair and blood are credible indicators, urine is the preferred biological medium for the determination of exposure to inorganic mercury, including elemental mercury, with blood normally being of value only if exposure is ongoing. Although treatments are available to help rid the body of mercury in cases of extreme exposure, prevention of exposure will make such treatments unnecessary. Knowing the sources of mercury and avoiding unnecessary exposure are the prudent ways of preventing mercury intoxication. When exposure occurs, it should be kept in mind that not all unwanted exposures will result in adverse health consequences. In all cases, elimination of the source of exposure should be the first priority of public health officials. PMID:18044248

  1. The interaction integral for fracture of orthotropic functionally graded materials: evaluation

    E-print Network

    Paulino, Glaucio H.

    and mixed-mode two-dimensional problems are evaluated by means of the interaction integral and the finite., 2002). These multifunctional materials were introduced to take advantage of ideal behavior of itsThe interaction integral for fracture of orthotropic functionally graded materials: evaluation

  2. Programmable gradational micropatterning of functional materials using maskless lithography controlling absorption

    NASA Astrophysics Data System (ADS)

    Jung, Yushin; Lee, Howon; Park, Tae-Joon; Kim, Sungsik; Kwon, Sunghoon

    2015-10-01

    The demand for patterning functional materials precisely on surfaces of stimuli-responsive devices has increased in many research fields. In situ polymerization technology is one of the most convenient ways to place the functional materials on a desired location with micron-scale accuracy. To fabricate stimuli-responsive surfaces, controlling concentration of the functional material is much as important as micropatterning them. However, patterning and controlling concentration of the functional materials simultaneously requires an additional process, such as preparing multiple co-flow microfluidic structures and numbers of solutions with various concentrations. Despite applying these processes, fabricating heterogeneous patterns in large scale (millimeter scale) is still impossible. In this study, we propose an advanced in situ polymerization technique to pattern the surface in micron scale in a concentration-controlled manner. Because the concentration of the functional materials is manipulated by self-assembly on the surface, a complex pattern could be easily fabricated without any additional procedure. The complex pattern is pre-designed with absorption amount of the functional material, which is pre-determined by the duration of UV exposure. We show that the resolution reaches up to 2.5??m and demonstrate mm-scale objects, maintaining the same resolution. We also fabricated Multi-bit barcoded micro particles verify the flexibility of our system.

  3. Programmable gradational micropatterning of functional materials using maskless lithography controlling absorption

    PubMed Central

    Jung, Yushin; Lee, Howon; Park, Tae-Joon; Kim, Sungsik; Kwon, Sunghoon

    2015-01-01

    The demand for patterning functional materials precisely on surfaces of stimuli-responsive devices has increased in many research fields. In situ polymerization technology is one of the most convenient ways to place the functional materials on a desired location with micron-scale accuracy. To fabricate stimuli-responsive surfaces, controlling concentration of the functional material is much as important as micropatterning them. However, patterning and controlling concentration of the functional materials simultaneously requires an additional process, such as preparing multiple co-flow microfluidic structures and numbers of solutions with various concentrations. Despite applying these processes, fabricating heterogeneous patterns in large scale (millimeter scale) is still impossible. In this study, we propose an advanced in situ polymerization technique to pattern the surface in micron scale in a concentration-controlled manner. Because the concentration of the functional materials is manipulated by self-assembly on the surface, a complex pattern could be easily fabricated without any additional procedure. The complex pattern is pre-designed with absorption amount of the functional material, which is pre-determined by the duration of UV exposure. We show that the resolution reaches up to 2.5??m and demonstrate mm-scale objects, maintaining the same resolution. We also fabricated Multi-bit barcoded micro particles verify the flexibility of our system. PMID:26490360

  4. Mission and spacecraft support functions of the Materials Engineering Branch: A space oriented technology resource

    NASA Technical Reports Server (NTRS)

    Fisher, A.; Staugaitis, C. L.

    1974-01-01

    The capabilities of the Materials Engineering Branch (MEB) of the Goddard Space Flight Center, Greenbelt, Maryland, are surveyed. The specific functions of spacecraft materials review, materials processing and information dissemination, and laboratory support, are outlined in the Activity Report. Further detail is provided by case histories of laboratory satellite support and equipment. Project support statistics are shown, and complete listings of MEB publications, patents, and tech briefs are included. MEB staff, and their respective discipline areas and spacecraft liaison associations, are listed.

  5. Inorganic Crystal Structure Database (ICSD)

    National Institute of Standards and Technology Data Gateway

    SRD 84 FIZ/NIST Inorganic Crystal Structure Database (ICSD) (PC database for purchase)   The Inorganic Crystal Structure Database (ICSD) is produced cooperatively by the Fachinformationszentrum Karlsruhe(FIZ) and the National Institute of Standards and Technology (NIST). The ICSD is a comprehensive collection of crystal structure data of inorganic compounds containing more than 140,000 entries and covering the literature from 1915 to the present.

  6. Alkali deposits found in biomass boilers: The behavior of inorganic material in biomass-fired power boilers -- Field and laboratory experiences. Volume 2

    SciTech Connect

    Baxter, L.L.; Miles, T.R.; Miles, T.R. Jr.; Jenkins, B.M.; Dayton, D.C.; Milne, T.A.; Bryers, R.W.; Oden, L.L.

    1996-03-01

    This report documents the major findings of the Alkali Deposits Investigation, a collaborative effort to understand the causes of unmanageable ash deposits in biomass-fired electric power boilers. Volume 1 of this report provide an overview of the project, with selected highlights. This volume provides more detail and discussion of the data and implications. This document includes six sections. The first, the introduction, provides the motivation, context, and focus for the investigation. The remaining sections discuss fuel properties, bench-scale combustion tests, a framework for considering ash deposition processes, pilot-scale tests of biomass fuels, and field tests in commercially operating biomass power generation stations. Detailed chemical analyses of eleven biomass fuels representing a broad cross-section of commercially available fuels reveal their properties that relate to ash deposition tendencies. The fuels fall into three broad categories: (1) straws and grasses (herbaceous materials); (2) pits, shells, hulls and other agricultural byproducts of a generally ligneous nature; and (3) woods and waste fuels of commercial interest. This report presents a systematic and reasonably detailed analysis of fuel property, operating condition, and boiler design issues that dictate ash deposit formation and property development. The span of investigations from bench-top experiments to commercial operation and observations including both practical illustrations and theoretical background provide a self-consistent and reasonably robust basis to understand the qualitative nature of ash deposit formation in biomass boilers. While there remain many quantitative details to be pursued, this project encapsulates essentially all of the conceptual aspects of the issue. It provides a basis for understanding and potentially resolving the technical and environmental issues associated with ash deposition during biomass combustion. 81 refs., 124 figs., 76 tabs.

  7. Synthesis, characterization and application of functional carbon nano materials

    NASA Astrophysics Data System (ADS)

    Chu, Jin

    The synthesis, characterizations and applications of carbon nanomaterials, including carbon nanorods, carbon nanosheets, carbon nanohoneycombs and carbon nanotubes were demonstrated. Different growth techniques such as pulsed laser deposition, DC/RF sputtering, hot filament physical vapour deposition, evaporative casting and vacuum filtration methods were introduced or applied for synthesizing carbon nanomaterials. The morphology, chemical compositions, bond structures, electronic, mechanical and sensing properties of the obtained samples were investigated. Tilted well-aligned carbon micro- and nano- hybrid rods were fabricated on Si at different substrate temperatures and incident angles of carbon source beam using the hot filament physical vapour deposition technique. The morphologic surfaces and bond structures of the oblique carbon rod-like structures were investigated by scanning electron microscopy, field emission scanning electron microscopy, transmission electron diffraction and Raman scattering spectroscopy. The field emission behaviour of the fabricated samples was also tested. Carbon nanosheets and nanohoneycombs were also synthesized on Si substrates using a hot filament physical vapor deposition technique under methane ambient and vacuum, respectively. The four-point Au electrodes are then sputtered on the surface of the nanostructured carbon films to form prototypical humidity sensors. The sensing properties of prototypical sensors at different temperature, humidity, direct current, and alternative current voltage were characterized. Linear sensing response of sensors to relative humidity ranging from 11% to 95% is observed at room temperature. Experimental data indicate that the carbon nanosheets based sensors exhibit an excellent reversible behavior and long-term stability. It also has higher response than that of the humidity sensor with carbon nanohoneycombs materials. Conducting composite films containing carbon nanotubes (CNTs) were prepared in two different ways of evaporative casting and vacuum filtration methods using the biopolymer kappa-carrageenan (KC) as a dispersant. Evaporative casting and vacuum filtration film-formation processes were compared by testing electrical properties. Results showed that films produced using vacuum filtration had higher electrical properties than those prepared using the evaporative casting method. The evaporative casted multi walled carbon nanotubes composite films also performed as the best humidity sensor over all other films measured.

  8. Laser ablation particle beam glow discharge time of flight mass spectrometry for the analysis of halogenated polymers and inorganic solid material

    NASA Astrophysics Data System (ADS)

    Fliegel, Daniel; Günther, Detlef

    2009-05-01

    A laser ablation particle beam pulsed glow discharge mass spectrometer (LA-PB-GD-TOFMS) was designed and used for fundamental studies. The instrument consists of a three stage aerodynamic lens system, a hollow cathode pulsed glow discharge and a time-of-flight mass spectrometer. The particle beam interface was constructed to provide an efficient particle transfer into the hollow cathode. Calculations showed that particles between 1 and 3000 nm in diameter are able to pass through this interface. Glass and metal (SRM NIST610 and CRM JK37) ablated by laser ablation and introduced into a pulsed, He glow discharge showed no ionization, even for major elements such as 27Al +, 28Si +, 23Na + or 56Fe +. This can be explained by the low gas temperature of a pulsed glow discharge which is not sufficient to vaporize particles with high melting and vaporization points. In contrast, ablated particles of soft materials such as PTFE or PVC polymers were vaporized and ionized in a pulsed glow discharge. Ion signals for elements such as carbon ( 12C +), hydrogen ( 1H 3+), fluorine ( 19F +) and chlorine ( 35/37Cl +) were detected when generating an aerosol by laser ablation and introduced into the hollow cathode. Furthermore, various fragments such as 12C x1H v19F y+ and 12C x1H v35/37Cl y+ were identified and provide a "fingerprint" of the ablated polymer. The influence of the laser fluence and glow discharge voltage was investigated with respect to the ratio of fragments to elemental ion signals. The decrease in laser energy leads to an increase of the 12C +/ 12C 19F x+ ratio. Lowering the glow discharge plasma power favors the appearance of fragments such as 12C 19F x+ whereas higher plasma power favors the ion signals of the elements, such as 12C + and 19F +. A set of experiments comparing different PVC polymers with increasing PVC content was evaluated with respect to the 12C +/ 35Cl + ratio. A correlation between the ratio and the concentration of the PVC in the sample was determined and indicates the capability for quantitative analysis of halogens in organic particulate matter by LA-PB-GD-TOFMS.

  9. 2013 INORGANIC REACTION MECHANISMS GORDON RESEARCH CONFERENCE (MARCH 3-8, 2013 - HOTEL GALVEZ, GALVESTON TX)

    SciTech Connect

    Abu-Omar, Mahdi M.

    2012-12-08

    The 2013 Gordon Conference on Inorganic Reaction Mechanisms will present cutting-edge research on the molecular aspects of inorganic reactions involving elements from throughout the periodic table and state-of-the art techniques that are used in the elucidation of reaction mechanisms. The Conference will feature a wide range of topics, such as homogeneous and heterogeneous catalysis, metallobiochemistry, electron-transfer in energy reactions, polymerization, nitrogen fixation, green chemistry, oxidation, solar conversion, alkane functionalization, organotransition metal chemistry, and computational chemistry. The talks will cover themes of current interest including energy, materials, and bioinorganic chemistry. Sections cover: Electron-Transfer in Energy Reactions; Catalytic Polymerization and Oxidation Chemistry; Kinetics and Spectroscopy of Heterogeneous Catalysts; Metal-Organic Chemistry and its Application in Synthesis; Green Energy Conversion;Organometallic Chemistry and Activation of Small Molecules; Advances in Kinetics Modeling and Green Chemistry; Metals in Biology and Disease; Frontiers in Catalytic Bond Activation and Cleavage.

  10. Energetics and dynamics in organic-inorganic halide perovskite photovoltaics and light emitters.

    PubMed

    Sum, Tze Chien; Chen, Shi; Xing, Guichuan; Liu, Xinfeng; Wu, Bo

    2015-08-28

    The rapid transcendence of organic-inorganic metal halide perovskite solar cells to above the 20% efficiency mark has captivated the broad photovoltaic community. As the efficiency race continues unabated, it is essential that fundamental studies keep pace with these developments. Further gains in device efficiencies are expected to be increasingly arduous and harder to come by. The key to driving the perovskite solar cell efficiencies towards their Shockley-Queisser limit is through a clear understanding of the interfacial energetics and dynamics between perovskites and other functional materials in nanostructured- and heterojunction-type devices. In this review, we focus on the current progress in basic characterization studies to elucidate the interfacial energetics (energy-level alignment and band bending) and dynamical processes (from the ultrafast to the ultraslow) in organic-inorganic metal halide perovskite photovoltaics and light emitters. Major findings from these studies will be distilled. Open questions and scientific challenges will also be highlighted. PMID:26234397

  11. Energetics and dynamics in organic-inorganic halide perovskite photovoltaics and light emitters

    NASA Astrophysics Data System (ADS)

    Chien Sum, Tze; Chen, Shi; Xing, Guichuan; Liu, Xinfeng; Wu, Bo

    2015-08-01

    The rapid transcendence of organic-inorganic metal halide perovskite solar cells to above the 20% efficiency mark has captivated the broad photovoltaic community. As the efficiency race continues unabated, it is essential that fundamental studies keep pace with these developments. Further gains in device efficiencies are expected to be increasingly arduous and harder to come by. The key to driving the perovskite solar cell efficiencies towards their Shockley-Queisser limit is through a clear understanding of the interfacial energetics and dynamics between perovskites and other functional materials in nanostructured- and heterojunction-type devices. In this review, we focus on the current progress in basic characterization studies to elucidate the interfacial energetics (energy-level alignment and band bending) and dynamical processes (from the ultrafast to the ultraslow) in organic-inorganic metal halide perovskite photovoltaics and light emitters. Major findings from these studies will be distilled. Open questions and scientific challenges will also be highlighted.

  12. Deep eutectic solvents: sustainable media for nanoscale and functional materials.

    PubMed

    Wagle, Durgesh V; Zhao, Hua; Baker, Gary A

    2014-08-19

    Deep eutectic solvents (DESs) represent an alternative class of ionic fluids closely resembling room-temperature ionic liquids (RTILs), although, strictly speaking, they are distinguished by the fact that they also contain an organic molecular component (typically, a hydrogen bond donor like a urea, amide, acid, or polyol), frequently as the predominant constituent. Practically speaking, DESs are attractive alternatives to RTILs, sharing most of their remarkable qualities (e.g., tolerance to humidity, negligible vapor pressure, thermostability, wide electrochemical potential windows, tunability) while overcoming several limitations associated with their RTIL cousins. Particularly, DESs are typically, less expensive, more synthetically accessible (typically, from bulk commodity chemicals using solvent/waste-free processes), nontoxic, and biodegradable. In this Account, we provide an overview of DESs as designer solvents to create well-defined nanomaterials including shape-controlled nanoparticles, electrodeposited films, metal-organic frameworks, colloidal assemblies, hierarchically porous carbons, and DNA/RNA architectures. These breakthroughs illustrate how DESs can fulfill multiple roles in directing chemistry at the nanoscale: acting as supramolecular template, metal/carbon source, sacrificial agent (e.g., ammonia release from urea), and/or redox agent, all in the absence of formal stabilizing ligand (here, solvent and stabilizer are one and the same). The ability to tailor the physicochemical properties of DESs is central to controlling their interfacial behavior. The preorganized "supramolecular" nature of DESs provides a soft template to guide the formation of bimodal porous carbon networks or the evolution of electrodeposits. A number of essential parameters (viscosity, polarity, surface tension, hydrogen bonding), plus coordination with solutes/surfaces, all play significant roles in modulating species reactivity and mass transport properties governing the genesis of nanostructure. Furthermore, DES components may modulate nucleation and growth mechanisms by charge neutralization, modification of reduction potentials (or chemical activities), and passivation of particular crystal faces, dictating growth along preferred crystallographic directions. Broad operational windows for electrochemical reactions coupled with their inherent ionic nature facilitate the electrodeposition of alloys and semiconductors inaccessible to classical means and the use of cosolvents or applied potential control provide under-explored strategies for mediating interfacial interactions leading to control over film characteristics. The biocompatibility of DESs suggests intriguing potential for the construction of biomolecular architectures in these novel media. It has been demonstrated that nucleic acid structures can be manipulated in the ionic, crowded, dehydrating (low water activity) DES environment-including the adoption of duplex helical structures divergent from the canonical B form and parallel G-quadruplex DNA persisting near water's boiling point-challenging the misconception that water is a necessity for maintenance of nucleic acid structure/functionality and suggesting an enticing trajectory toward DNA/RNA-based nanocatalysis within a strictly anhydrous medium. DESs offer tremendous opportunities and open intriguing perspectives for generating sophisticated nanostructures within an anhydrous or low-water medium. We conclude this Account by offering our thoughts on the evolution of the field, pointing to areas of clear and compelling utility which will surely see fruition in the coming years. Finally, we highlight a few hurdles (e.g., need for a universal nomenclature, absence of water-immiscible, oriented-phase, and low-viscosity DESs) which, once navigated, will hasten progress in this area. PMID:24892971

  13. Supplementary Materials: A Partition Function Algorithm for Interacting Nucleic Acid Strands

    E-print Network

    Will, Sebastian

    Supplementary Materials: A Partition Function Algorithm for Interacting Nucleic Acid Strands the partition function of two interacting nucleic acid strands. We also present the sequence pairs in the data nucleic acid strands by R and S. Strand R is indexed from 1 to LR, and S is indexed from 1 to LS both in 5

  14. ARTICLE IN PRESS Sex influences on material-sensitive functional lateralization in

    E-print Network

    ARTICLE IN PRESS Sex influences on material-sensitive functional lateralization in working 19 January 2006 Research investigating the effects of sex on the lateralization of language functions has produced mixed results to date, with some studies finding sex differences and others not (Shaywitz

  15. Comparison of the Electron Localization Function and Deformation Electron Density Maps for Selected Earth Materials

    E-print Network

    Downs, Robert T.

    Comparison of the Electron Localization Function and Deformation Electron Density Maps for Selected 20, 2005; In Final Form: August 17, 2005 The electron localization function (ELF) and experimental and theoretical deformation electron density maps are compared for several earth materials and one representative

  16. Surface Science Letters Tuning the chemical functionality of a gas sensitive material

    E-print Network

    Diebold, Ulrike

    in an increased conductivity [8]. The mechanism by which water adsorption induces the band bending necessarySurface Science Letters Tuning the chemical functionality of a gas sensitive material: Water and density functional theory studies show that water adsorbs dissociatively on the SnO2(101) surface

  17. Supplementary material to "Curvature and frontier orbital energies in density functional theory", by Stein et al.

    E-print Network

    Baer, Roi

    Supplementary material to "Curvature and frontier orbital energies in density functional theory and frontier orbital energies in density functional theory", by Stein et al. 2. Calculation of curvature from)KS spin-orbitals , where is the orbital number and is the up or down spin (Alternate Latin and Greek

  18. Organic-Inorganic Composites of Semiconductor Nanocrystals for Efficient Excitonics.

    PubMed

    Guzelturk, Burak; Demir, Hilmi Volkan

    2015-06-18

    Nanocomposites of colloidal semiconductor nanocrystals integrated into conjugated polymers are the key to soft-material hybrid optoelectronics, combining advantages of both plastics and particles. Synergic combination of the favorable properties in the hybrids of colloidal nanocrystals and conjugated polymers offers enhanced performance and new functionalities in light-generation and light-harvesting applications, where controlling and mastering the excitonic interactions at the nanoscale are essential. In this Perspective, we highlight and critically consider the excitonic interactions in the organic-inorganic nanocomposites to achieve highly efficient exciton transfer through rational design of the nanocomposites. The use of strong excitonic interactions in optoelectronic devices can trigger efficiency breakthroughs in hybrid optoelectronics. PMID:26266593

  19. High throughput screening of substrates for synthesis and functionalization of 2D materials

    NASA Astrophysics Data System (ADS)

    Singh, Arunima K.; Mathew, Kiran; Davydov, Albert V.; Hennig, Richard G.; Tavazza, Francesca

    2015-08-01

    Several two-dimensional (2D) materials have been synthesized experimentally, but many theoretically predicted 2D materials are yet to be synthesized. Here, we will review a density-functional theory based framework to enable high-throughput screening of suitable substrates for the stabilization and functionalization of 2D layers. A Materials Project based open source python tool, MPInterfaces, based on this framework, is being developed to automate the search of suitable substrates as well as to characterize their effect on the structural and electronic properties of 2D materials. Lattice-matching, symmetry-matching, substrate surface termination, configuration sampling, substrate induced structural distortion and doping estimation algorithms are being developed and will be described in this article. This computational tool will be employed to identify suitable substrates for scores of technologically relevant 2D materials, leading to acceleration of their synthesis and application, and more efficient use of experimental resources.

  20. Cohesive Modeling of Dynamic Crack Growth in Homogeneous and Functionally Graded Materials

    SciTech Connect

    Zhang Zhengyu; Paulino, Glaucio H.; Celes, Waldemar

    2008-02-15

    This paper presents a Cohesive Zone Model (CZM) approach for investigating dynamic crack propagation in homogeneous and Functionally Graded Materials (FGMs). The failure criterion is incorporated in the CZM using both a finite cohesive strength and work to fracture in the material description. A novel CZM for FGMs is explored and incorporated into a finite element framework. The material gradation is approximated at the element level using a graded element formulation. A numerical example is provided to demonstrate the efficacy of the CZM approach, in which the influence of the material gradation on the crack growth pattern is studied.

  1. Casting inorganic structures with DNA molds

    PubMed Central

    Sun, Wei; Boulais, Etienne; Hakobyan, Yera; Wang, Wei Li; Guan, Amy; Bathe, Mark; Yin, Peng

    2014-01-01

    We report a general strategy for designing and synthesizing inorganic nanostructures with arbitrarily prescribed three-dimensional shapes. Computationally designed DNA strands self-assemble into a stiff “nano-mold” that contains a user-specified three-dimensional cavity and encloses a nucleating gold “seed”. Under mild conditions, this seed grows into a larger cast structure that fills and thus replicates the cavity. We synthesized a variety of nanoparticles with three nanometer resolution: three distinct silver cuboids with three independently tunable dimensions, silver and gold nanoparticles with diverse cross sections, and composite structures with homo-/heterogeneous components. The designer equilateral silver triangular and spherical nanoparticles exhibited plasmonic properties consistent with electromagnetism-based simulations. Our framework is generalizable to more complex geometries and diverse inorganic materials, offering a range of applications in biosensing, photonics, and nanoelectronics. PMID:25301973

  2. Detonation Properties Measurements for Inorganic Explosives

    NASA Astrophysics Data System (ADS)

    Morgan, Brent A.; Lopez, Angel

    2005-03-01

    Many commonly available explosive materials have never been quantitatively or theoretically characterized in a manner suitable for use in analytical models. This includes inorganic explosive materials used in spacecraft ordnance, such as zirconium potassium perchlorate (ZPP). Lack of empirical information about these materials impedes the development of computational techniques. We have applied high fidelity measurement techniques to experimentally determine the pressure and velocity characteristics of ZPP, a previously uncharacterized explosive material. Advances in measurement technology now permit the use of very small quantities of material, thus yielding a significant reduction in the cost of conducting these experiments. An empirical determination of the explosive behavior of ZPP derived a Hugoniot for ZPP with an approximate particle velocity (uo) of 1.0 km/s. This result compares favorably with the numerical calculations from the CHEETAH thermochemical code, which predicts uo of approximately 1.2 km/s under ideal conditions.

  3. An optimum approximation of n-point correlation functions of random heterogeneous material systems

    SciTech Connect

    Baniassadi, M.; Garmestani, H.; Ahzi, S.; Remond, Y.

    2014-02-21

    An approximate solution for n-point correlation functions is developed in this study. In the approximate solution, weight functions are used to connect subsets of (n-1)-point correlation functions to estimate the full set of n-point correlation functions. In previous related studies, simple weight functions were introduced for the approximation of three and four-point correlation functions. In this work, the general framework of the weight functions is extended and derived to achieve optimum accuracy for approximate n-point correlation functions. Such approximation can be utilized to construct global n-point correlation functions for a system when there exist limited information about these functions in a subset of space. To verify its accuracy, the new formulation is used to approximate numerically three-point correlation functions from the set of two-point functions directly evaluated from a virtually generated isotropic heterogeneous microstructure representing a particulate composite system. Similarly, three-point functions are approximated for an anisotropic glass fiber/epoxy composite system and compared to their corresponding reference values calculated from an experimental dataset acquired by computational tomography. Results from both virtual and experimental studies confirm the accuracy of the new approximation. The new formulation can be utilized to attain a more accurate approximation to global n-point correlation functions for heterogeneous material systems with a hierarchy of length scales.

  4. Zinc oxide (ZnO) has attracted much interest during last decades as a functional material. It has been known as a conductive material when elements such as indium, gallium and aluminum are doped.

    E-print Network

    oxide (ITO), graphene, and carbon nanotube film. In addition, a new generation solar cell electrodes. The nanostructures for solar cells using inorganic materials such as silicon (Si), titanium oxide (TiO2), and ZnO have been an interesting topic for research in solar cell community in order

  5. A color-tunable luminescent material with functionalized graphitic carbon nitride as multifunctional supports

    NASA Astrophysics Data System (ADS)

    Lu, Jiutian; Cao, Yudong; Fan, Hai; Hou, Juying; Ai, Shiyun

    2015-12-01

    A color-tunable luminescent material was prepared based on the composition of functionalized graphitic carbon nitride (g-C3N4) and europium (III). The functionalized g-C3N4 layers not only behave as multifunctional supports including ligand coordinated with europium (III) and a support structure for the formation of the luminescent material, but exhibit excitation wavelength-dependent luminescence, thus the energy transfer between the functionalized g-C3N4 and europium (III) can match very well by controlling the emission wavelength of functionalized g-C3N4. The as-prepared materials was comprehensively characterized via X-ray photoelectron spectroscopy, Fourier Transform Infrared spectroscopy, X-ray scattering techniques, Ultraviolet and Visible spectrophotometer, fluorescence spectrophotometer, thermogravimetric analysis, etc. The luminescent material exhibits multi-color emissions which are consistent with the characteristic emissions of europium (III) and functionalized g-C3N4, and the photoluminescence quality and density of the europium (III) can be greatly enhanced. The brilliant optical properties of the materials make them suiting for multipurpose applications in practical fields.

  6. Effects of functionally graded materials on dynamics of molecular bond clusters

    NASA Astrophysics Data System (ADS)

    Zhang, WenLiang; Qian, Jin; Yao, HaiMin; Chen, WeiQiu; Gao, HuaJian

    2012-06-01

    Unlike nonspecific adhesion of conventional hard materials in engineering commonly described by JKR and DMT type models, the molecular adhesion via specific receptor-ligand bonds is stochastic by nature and has the feature that its strength strongly depends on the medium stiffness surrounding the adhesion. In this paper, we demonstrate in a stochastic-elasticity framework that a type of materials with linearly graded elastic modulus can be designed to achieve "equal load sharing" and enhanced cooperative rebinding among interfacial molecular bonds. Upon modulus gradation, multiple molecular bonds can be elastically decoupled but statistically cooperative. In general, uniform molecular adhesion can be accomplished by two strategies: homogeneous materials with sufficient stiffness higher than a threshold or heterogeneous materials satisfying the criterion on modulus gradation. These results not only provide a theoretical principle for possible applications of functionally graded materials in quantitatively controlling cell-matrix adhesion, but also have general implications on adhesion between soft materials mediated by specific molecular binding.

  7. Immobilization of lipase and keratinase on functionalized SBA-15 nanostructured materials

    NASA Astrophysics Data System (ADS)

    Le, Hy G.; Vu, Tuan A.; Tran, Hoa T. K.; Dang, Phuong T.

    2013-12-01

    SBA-15 nanostructured materials were synthesized via hydrothermal treatment and were functionalized with 3- aminopropyltriethoxysilane (APTES). The obtained samples were characterized by different techniques such as XRD, BET, TEM, IR and DTA. After functionalization, it showed that these nanostrucrured materials still maintained the hexagonal pore structure of the parent SBA-15. The model enzyms chosen in this study were lipase and keratinase. Lipase was a biocatalyst for hydrolyzation of long chain triglycerides or methyl esters of long chain alcohols and fatty acids; keratinase is a proteolytic enzyme that catalyzes the cleavage of keratin. The functionalized SBA-15 materials were used to immobilize lipase and keratinase, exhibiting higher activity than that of the unfunctionalized pure silica SBA-15 ones. This might be due to the enhancing of surface hydrophobicity upon functionalization. The surface functionalization of the nanostructured silicas with organic groups can favor the interaction between enzyme and the supports and consequently increasing the operational stability of the immobilized enzymes. The loading of lipase on functionalized SBA-15 materials was higher than that of keratinase. This might be rationalized by the difference in size of enzyms.

  8. Self-response multi-functional composite material base on carbon nanotube paper using deicing, flame retardancy, thermal insulation, and lightning-strike protection

    NASA Astrophysics Data System (ADS)

    Chu, Hetao; Zhang, Zhichun; Liu, Yanju; Leng, Jinsong

    2015-04-01

    Carbon nanotube paper (CNP) based multi-functional composite material is an attractive candidate for deicing, flame retardancy, thermal insulation and lighting strike protection due to the excellent conductivity, light weight and thin dimensions. In this article, multi-functional carbon nanotube paper was fabricated successfully by using commercial carbon nanotube. As a deicing composite material, carbon nanotube was used directly without pretreatment in fabricating carbon nanotube paper. The conductivities of the carbon nanotube paper and deicing composite were 77.8S/cm and 64.9S/ respectively. Electrical heating and deicing performance were test by infrared camera with deicing time less than 220s and 450s to melt a certain amount of ice under different ambient condition. CNT was grafted by zirconium (IV) butoxide solution and dimethyl dichlorosilicane to form co-oligomers on the tube surface while oligomers decompose under a certain temperature to develop an inorganic layer of silicon zirconium oxide. The oxidizing temperature of carbon nanotube increases more than 20°C and the weight loss rate decreases 20% than the untreated carbon nanotube. Lightning protection material required high electro conductivity, due to the utmost high current in a short time. Therefore, silver nanoparticles were deposited on the surface of carbon nanotube with the diameter around 100nm. The conductivity increased sharply from 84s/cm to1756s/cm with the mount of 5.9wt% Ag of the modified carbon nanotube paper because the silver nanoparticles deposited on the surface. In addition, the silver modified also can be used as thermal insulation material decreasing the infrared radiation.

  9. Early Transition Metal Oxides as Catalysts: Crossing Scales from Clusters to Single Crystals to Functioning Materials

    SciTech Connect

    Dixon, David A.; Dohnalek, Zdenek; Gutowski, Maciej S.; Hu, Jian Zhi; Iglesia, Enrique; Kay, Bruce D.; Liu, Jun; Peden, Charles HF; Wang, Lai; Wang, Yong; White, John M.; Bondarchuk, Oleksander A.; Herrera, Jose E.; Kim, J.; Kwak, Ja Hun; Stuchinskaya, T.; Zhai, Hua Jin; Chisolm, Claire N.; Macht, Josef

    2007-05-20

    The proportion of chemical industry processes using catalysts exceeds 80%. Current commercial heterogeneous catalysts are structurally and chemically complex and data gathered from them can seldom be interpreted with atomic-level precision. We seek to reduce the complexity of TMO catalysts to levels addressable and controllable at the atomic level, while maintaining intimate linkages with practical catalysis and catalytic materials. The focus of the proposed work is to gain a fundamental understanding of chemical transformations in order to design and construct new catalysts with more precise control of specific chemical reactions. We are employing an integrated experimental/theoretical approach to advance our current ability to understand, design, and control the catalytic and surface chemistry of transition metal oxides, specifically for redox and acid-base chemistries. The approach combines novel solid-state inorganic synthesis, surface science, experimental and theoretical/computational chemical physics, and mechanistic organic chemistry to address this complex and important challenge. Selected highlights from the results obtained in the last year are presented in the conference proceedings extended abstract.

  10. Prediction of the adhesive behavior of bio-inspired functionally graded materials against rough surfaces

    NASA Astrophysics Data System (ADS)

    Peijian, Chen; Juan, Peng; Yucheng, Zhao; Feng, Gao

    2014-06-01

    Roughness effect and adhesion properties are important characteristics to be accessed in the development of functionally graded materials for biological and biomimetic applications, particularly for the hierarchical composition in biomimetic gecko robot. A multi-asperities adhesion model to predict the adhesive forces is presented in this work. The effect of surface roughness and graded material properties, which significantly alter the adhesive strength between contact bodies, can be simultaneously considered in the generalized model. It is found that proper interfacial strength can be controlled by adjusting surface roughness ? / R, graded exponent k and material parameter E*R / ??. The results should be helpful in the design of new biomimetic materials and useful in application of micro functional instruments.

  11. Propagation of ultrasonic Love waves in nonhomogeneous elastic functionally graded materials.

    PubMed

    Kie?czy?ski, P; Szalewski, M; Balcerzak, A; Wieja, K

    2016-02-01

    This paper presents a theoretical study of the propagation behavior of ultrasonic Love waves in nonhomogeneous functionally graded elastic materials, which is a vital problem in the mechanics of solids. The elastic properties (shear modulus) of a semi-infinite elastic half-space vary monotonically with the depth (distance from the surface of the material). The Direct Sturm-Liouville Problem that describes the propagation of Love waves in nonhomogeneous elastic functionally graded materials is formulated and solved by using two methods: i.e., (1) Finite Difference Method, and (2) Haskell-Thompson Transfer Matrix Method. The dispersion curves of phase and group velocity of surface Love waves in inhomogeneous elastic graded materials are evaluated. The integral formula for the group velocity of Love waves in nonhomogeneous elastic graded materials has been established. The effect of elastic non-homogeneities on the dispersion curves of Love waves is discussed. Two Love wave waveguide structures are analyzed: (1) a nonhomogeneous elastic surface layer deposited on a homogeneous elastic substrate, and (2) a semi-infinite nonhomogeneous elastic half-space. Obtained in this work, the phase and group velocity dispersion curves of Love waves propagating in the considered nonhomogeneous elastic waveguides have not previously been reported in the scientific literature. The results of this paper may give a deeper insight into the nature of Love waves propagation in elastic nonhomogeneous functionally graded materials, and can provide theoretical guidance for the design and optimization of Love wave based devices. PMID:26482393

  12. Workshop on Functional Requirements for the Modeling of Fate and Transport of Waterborne CBRN Materials

    SciTech Connect

    Giles, GE

    2005-02-03

    The purpose of this Workshop on ''Functional Requirements for the Modeling of Fate and Transport of Waterborne CBRN Materials'' was to solicit functional requirements for tools that help Incident Managers plan for and deal with the consequences of industrial or terrorist releases of materials into the nation's waterways and public water utilities. Twenty representatives attended and several made presentations. Several hours of discussions elicited a set of requirements. These requirements were summarized in a form for the attendees to vote on their highest priority requirements. These votes were used to determine the prioritized requirements that are reported in this paper and can be used to direct future developments.

  13. Organic/inorganic nanocomposites, methods of making, and uses as a permeable reactive barrier

    DOEpatents

    Harrup, Mason K. (Idaho Falls, ID); Stewart, Frederick F. (Idaho Falls, ID)

    2007-05-15

    Nanocomposite materials having a composition including an inorganic constituent, a preformed organic polymer constituent, and a metal ion sequestration constituent are disclosed. The nanocomposites are characterized by being single phase, substantially homogeneous materials wherein the preformed polymer constituent and the inorganic constituent form an interpenetrating network with each other. The inorganic constituent may be an inorganic oxide, such as silicon dioxide, formed by the in situ catalyzed condensation of an inorganic precursor in the presence of the solvated polymer and metal ion sequestration constituent. The polymer constituent may be any hydrophilic polymer capable of forming a type I nanocomposite such as, polyacrylonitrile (PAN), polyethyleneoxide (PEO), polyethylene glycol (PEG), polyvinyl acetate (PVAc), polyvinyl alcohol (PVA), and combinations thereof. Nanocomposite materials of the present invention may be used as permeable reactive barriers (PRBs) to remediate contaminated groundwater. Methods for making nanocomposite materials, PRB systems, and methods of treating groundwater are also disclosed.

  14. Microstructure and properties of multiphase and functionally graded materials prepared by chemical vapor deposition

    SciTech Connect

    Lee, W.Y.

    1996-05-01

    The synthesis of multiphase and functionally graded materials by chemical vapor deposition is discussed from a perspective of controlling their composition and microstructure at a nano-scale level, and ultimately, tailoring their material properties. Prior research is briefly reviewed to address the current state of this novel material concept. Recent experimental results relating to controlling the selected properties of two multiphase systems, TiN + MoS{sub 2} and NiAl + Al{sub 2}O{sub 3}, are described to illustrate this concept`s potential merits and challenges for use in realistic applications.

  15. Green's function for SH-waves in a cylindrically monoclinic material

    NASA Astrophysics Data System (ADS)

    Watanabe, Kazumi; Payton, Robert G.

    2002-11-01

    Green's function for SH-waves in a cylindrically monoclinic material is considered for impulsive and time-harmonic sources. Closed form expressions for the Green's function are derived for a few limited values of anisotropic parameters. A very interesting time development of the wave front shape is illustrated and the wave front singularity is discussed for the transient SH-wave. Contours of the displacement amplitude for the time-harmonic wave are also shown.

  16. Exploration of new superconductors and functional materials, and fabrication of superconducting tapes and wires of iron pnictides

    NASA Astrophysics Data System (ADS)

    Hosono, Hideo; Tanabe, Keiichi; Takayama-Muromachi, Eiji; Kageyama, Hiroshi; Yamanaka, Shoji; Kumakura, Hiroaki; Nohara, Minoru; Hiramatsu, Hidenori; Fujitsu, Satoru

    2015-06-01

    This review shows the highlights of a 4-year-long research project supported by the Japanese Government to explore new superconducting materials and relevant functional materials. The project found several tens of new superconductors by examining ?1000 materials, each of which was chosen by Japanese experts with a background in solid state chemistry. This review summarizes the major achievements of the project in newly found superconducting materials, and the fabrication wires and tapes of iron-based superconductors; it incorporates a list of ?700 unsuccessful materials examined for superconductivity in the project. In addition, described are new functional materials and functionalities discovered during the project.

  17. From chemistry to materials, design and photophysics of functional terbium molecular hybrids from assembling covalent chromophore to alkoxysilanes through hydrogen transfer addition

    SciTech Connect

    Yan Bing . E-mail: byan@tongji.edu.cn; Ma Dongjie

    2006-07-15

    Two silica-based organic-inorganic hybrid materials composed of phenol (PHE) and ethyl-p-hydroxybenzoate derivatives (abbreviated as EPHBA) complexes were prepared via a sol-gel process. The active hydroxyl groups of PHE/EPHBA grafted by 3-(triethoxysilyl)-propyl isocyanate (TESPIC) through hydrogen transfer reaction were used as multi-functional bridged components, which can coordinate to Tb{sup 3+} with carbonyl groups, strongly absorb ultraviolet and effectively transfer energy to Tb{sup 3+} through their triplet excited state, as well as undergo polymerization or crosslinking reactions with tetraethoxysilane (TEOS), for anchoring terbium ions to the silica backbone. For comparison, two doped hybrid materials in which rare-earth complexes were just encapsulated in silica-based sol-gel matrices were also prepared. NMR, FT-IR, UV/vis absorption and luminescence spectroscopy were used to investigate the obtained hybrid materials. UV excitation in the organic component resulted in strong green emission from Tb{sup 3+} ions due to an efficient ligand-to-metal energy transfer mechanism. - Graphical abstract: The active hydroxyl groups of phenol/ethyl-p-hydroxybenzoate grafted by 3-(triethoxysilyl)-propyl isocyanate (TESPIC) through hydrogen transfer reaction were used as multi-functional bridged components, which can coordinate to Tb{sup 3+} with carbonyl groups, strongly absorb ultraviolet and effectively transfer energy to Tb{sup 3+} through their triplet excited state, as well as undergo polymerization or crosslinking reactions with tetraethoxysilane (TEOS), for anchoring terbium ions to the silica backbone with covalently bonded.

  18. Bridging the materials gap in catalysis: entrapment of molecular catalysts in functional supports and beyond.

    PubMed

    Thomas, Arne; Driess, Matthias

    2009-01-01

    Rising sun of the materials world: Tremendous efforts are being made to combine the potential of molecular catalysts with that of functional supports. An approach towards unifying homogeneous and heterogeneous catalysis is the entrapment of organometallic catalysts in a metal matrix, which leads to well-defined composites that are suitable as heterogeneous catalysts for hydrogenation of styrene and diphenylacetylene. PMID:19156652

  19. Antler Stiffness in Moose (Alces alces): Correlated Evolution of Bone Function and Material Properties?

    E-print Network

    Blob, Richard W.

    Antler Stiffness in Moose (Alces alces): Correlated Evolution of Bone Function and Material. In this study we per- formed three-point bending tests on bone specimens ex- tracted from antlers of moose the antler structure, between populations of moose, and between moose and other deer species. Be- cause

  20. Crack-tip stress fields in functionally graded materials with linearly varying properties

    E-print Network

    Rousseau, Carl-Ernst

    of the FGM is assumed to vary linearly along the gradation direction. The first six terms for a crack along com- ponent. A functionally graded material (FGM) is a composite consisting of two or more phases variation in an FGM with linearly varying elastic modulus is developed through an asymptotic analysis

  1. Micromechanics-based elastic model for functionally graded materials with particle interactions

    E-print Network

    Paulino, Glaucio H.

    - functional tasks by virtue of spatially tailored micro- structures. For instance, in a ceramic/metal FGM consists of the ability to provide structural support by virtue of the metallic portions of the FGM by virtue of the ceramic portions of the FGM. Several FGMs are manufactured by two phases of materials

  2. Composite materials comprising two jonal functions and methods for making the same

    DOEpatents

    Fareed, Ali Syed (Newark, DE); Garnier, John Edward (Newark, DE); Schiroky, Gerhard Hans (Newark, DE); Kennedy, Christopher Robin (Newark, DE); Sonuparlak, Birol (Longmont, CO)

    2001-01-01

    The present invention generally relates to mechanisms for preventing undesirable oxidation (i.e., oxidation protection mechanisms) in composite bodies. The oxidation protection mechanisms include getterer materials which are added to the composite body which gather or scavenge undesirable oxidants which may enter the composite body. The getterer materials may be placed into at least a portion of the composite body such that any undesirable oxidant approaching, for example, a fiber reinforcement, would be scavenged by (e.g., reacted with) the getterer. The getterer materials) may form at least one compound which acts as a passivation layer, and/or is able to move by bulk transport (e.g., by viscous flow as a glassy material) to a crack, and sealing the crack, thereby further enhancing the oxidation protection of the composite body. One or more ceramic filler materials which serve as reinforcements may have a plurality of super-imposed coatings thereon, at least one of which coatings may function as or contain an oxidation protection mechanism. Specifically, a coating comprising boron nitride which has been engineered or modified to contain some silicon exhibits improved corrosion resistance, specifically to oxygen and moisture. The coated materials may be useful as reinforcing materials in high performance composites to provide improved mechanical properties such as fracture toughness. The present invention also relates to improved composites which incorporate these materials, and to their methods of manufacture.

  3. Design and functionality of colloidal-crystal-templated materials--chemical applications of inverse opals.

    PubMed

    Stein, Andreas; Wilson, Benjamin E; Rudisill, Stephen G

    2013-04-01

    Templating with colloidal crystals composed of monodisperse spheres is a convenient chemical method to obtain porous materials with well-ordered periodicity and interconnected pore systems. The three-dimensionally ordered macroporous (3DOM) products or inverse opals are of interest for numerous applications, both for the optical properties related to structural color of these photonic crystal materials and because of their bicontinuous nanostructure, i.e., a continuous nanostructured skeleton with large interfacial area and a three-dimensionally interconnected pore system with low tortuosity. This review outlines various synthetic methods used to control the morphology of 3DOM materials with different compositions. It highlights aspects of the choice of colloidal particles, assembly of the colloidal crystal template, infiltration and processing, template removal, and other necessary modifications to enhance the functionality of the materials. It also considers syntheses within the confinement of 3DOM materials and summarizes characterization methods that are particularly useful in the analysis of 3DOM materials. The review then discusses chemical applications of 3DOM materials, namely sorption and controlled release, optical and electrochemical sensors, solar cells, lithium ion batteries, supercapacitors, fuel cells, and environmental and chemical fuel catalysis. A focus is on structural features and materials properties that enable these applications. PMID:23079696

  4. A transient FGM interlayer based approach to joining ceramics. [Functionally gradient materials

    SciTech Connect

    Glaeser, A.M.; Shalz, M.L.; Dalgleish, B.J.; Tomsia, A.P.

    1993-01-01

    In most cases, functionally gradient materials have been designed to produce a desirable property gradient in a material or in a joint region. In this paper, the concept of a transient gradient structure is introduced. The function of the intentional property discontinuities in these multilayer interlayers is to facilitate processing of assemblies and materials combinations that would be difficult to process using conventional bonding approaches. Specifically, the methods make use of a thin or partial layer of a low melting point transient liquid phase to facilitate bonding via brazing, yet produce refractory joints. Several mechanisms for consuming the transient liquid former are outlined, and examples of interlayer designs that exploit these mechanisms are presented. Specific results from experiments joining alumina to alumina via Cu/Pt/Cu, Cu/Ni/Cu, Cu/Nb/Cu and Sn/Nb/Sn interlayers are presented.

  5. Evaluation of functional substances in the selected food materials for space agriculture

    NASA Astrophysics Data System (ADS)

    Tomita-Yokotani, Kaori; Kimura, Yasuko; Yamashita, Masamichi; Kimura, Shunta; Sato, Seigo; Katoh, Hiroshi; Abe, Yusuke; Ajioka, Reiko

    We have been studying the useful life-support system in closed bio-ecosystem for space agriculture. We have already proposed the several species as food material, such as Nostoc sp. HK-01 and Prunnus sp., cyanobacterium and Japanese cherry tree, respectively. The cyanobacterium, Nostoc sp Hk-01, has high tolerances to several space environment. Furthermore, the woody plant materials have useful utilization elements in our habitation environment. The studies of woody plants under a space-environment in the vegetable kingdom have a high contribution to the study of various and exotic environmental responses, too. We have already found that they can produce the important functional substances for human. Here, we will show the evaluation of functional substances in the selected food materials under the possible conditions for space agriculture after cooking.

  6. Hybrid materials of SBA-16 functionalized by rare earth (Eu{sup 3+}, Tb{sup 3+}) complexes of modified beta-diketone (TTA and DBM): Covalently bonding assembly and photophysical properties

    SciTech Connect

    Li Yajuan; Yan Bing; Li Ying

    2010-04-15

    Novel mesoporous SBA-16 type of hybrids TTA-S16 and DBM-S16 were synthesized by co-condensation of modified beta-diketone (TTA-Si and DBM-Si, DBM=1,3-diphenyl-1,3- propanepione, TTA=2-thenoyltrifluoroacetone) and tetraethoxysilane (TEOS) in the presence of Pluronic F127 as template, which were confirmed by FTIR, XRD, {sup 29}Si CP-MAS NMR, and N{sub 2} adsorption measurements. Novel organic-inorganic mesoporous luminescent hybrid containing RE{sup 3+} (Eu{sup 3+}, Tb{sup 3+}) complexes covalently attached to the functionalized ordered mesoporous SBA-16 (TTA-S16 and DBM-S16), which were designated as bpy-RE-TTA-S16 and bpy-RE-DBM-S16, were obtained by sol-gel process. The luminescence properties of these resulting materials were characterized in detail, and the results reveal that mesoporous hybrid material bpy-Eu-TTA-S16 present stronger luminescent intensities, longer lifetimes, and higher luminescent quantum efficiencies than the corresponding DBM-containing materials bpy-Eu-DBM-S16, while bpy-Tb-DBM-S16 exhibit the stronger characteristic emission of Tb{sup 3+} and longer lifetime than the corresponding TTA-containing materials bpy-Tb-TTA-S16. - Graphical abstract: Novel organic-inorganic mesoporous luminescent hybrids containing RE{sup 3+} complex covalently attached to the beta-diketone-functionalized ordered mesoporous SBA-16, which were designated as bpy-RE-TTA-S16 and bpy-RE-DBM-S16, were obtained by sol-gel process.

  7. Dynamic Response of Layered TiB/Ti Functionally Graded Material Specimens

    SciTech Connect

    Byrd, Larry; Beberniss, Tim; Chapman, Ben; Cooley, Glenn; Feie, John

    2008-02-15

    This paper covers the dynamic response of rectangular (25.4x101.6x3.175 mm) specimens manufactured from layers of TiB/Ti. The layers contained volume fractions of TiB that varied from 0 to 85% and thus formed a functionally graded material. Witness samples of the 85% TiB material were also tested to provide a baseline for the statistical variability of the test techniques. Static and dynamic tests were performed to determine the in situ material properties and fundamental frequencies. Damping in the material/ fixture was also found from the dynamic response. These tests were simulated using composite beam theory which gave an analytical solution, and using finite element analysis. The response of the 85% TiB specimens was found to be much more uniform than the functionally graded material and the dynamic response more uniform than the static response. A least squares analysis of the data using the analytical solutions were used to determine the elastic modulus and Poisson's ratio of each layer. These results were used to model the response in the finite element analysis. The results indicate that current analytical and numerical methods for modeling the material give similar and adequate predictions for natural frequencies if the measured property values were used. The models did not agree as well if the properties from the manufacturer or those of Hill and Linn were used.

  8. Chiral selection on inorganic crystalline surfaces

    NASA Technical Reports Server (NTRS)

    Hazen, Robert M.; Sholl, David S.

    2003-01-01

    From synthetic drugs to biodegradable plastics to the origin of life, the chiral selection of molecules presents both daunting challenges and significant opportunities in materials science. Among the most promising, yet little explored, avenues for chiral molecular discrimination is adsorption on chiral crystalline surfaces - periodic environments that can select, concentrate and possibly even organize molecules into polymers and other macromolecular structures. Here we review experimental and theoretical approaches to chiral selection on inorganic crystalline surfaces - research that is poised to open this new frontier in understanding and exploiting surface-molecule interactions.

  9. Milling and mechanical alloying of inorganic nonmetallics

    NASA Technical Reports Server (NTRS)

    Kosmac, T.; Courtney, T. H.

    1992-01-01

    The versatility of high energy grinding for instigating mechanochemical reactions in inorganic systems has been studied. High-energy grinding can be used to produce amorphous carbon from synthetic graphite and some forms of natural graphite. Elemental sulfur can be amorphized by prolonged energy grinding. The presence of iron resulting from wear of the grinding media strongly affects phase transformations of alphaFe2O3 and mechanochemical reactions of this phase with ZnO and NiO. Data obtained confirm that low-temperature mechanochemical method is a robust process route for production of a wide range of materials.

  10. AFM characterization of nonwoven material functionalized by ZnO sputter coating

    SciTech Connect

    Deng Bingyao; Yan Xiong; Wei Qufu Gao Weidong

    2007-10-15

    Sputter coatings provide new approaches to the surface functionalization of textile materials. In this study, polyethylene terephthalate (PET) nonwoven material was used as a substrate for creating functional nanostructures on the fiber surfaces. A magnetron sputter coating was used to deposit functional zinc oxide (ZnO) nanostructures onto the nonwoven substrate. The evolution of the surface morphology of the fibers in the nonwoven web was examined using atomic force microscopy (AFM). The AFM observations revealed a significant difference in the morphology of the fibers before and after the sputter coating. The AFM images also indicated the effect of the sputtering conditions on the surface morphology of the fibers. The increase in the sputtering time led to the growth of the ZnO grains on the fiber surfaces. The higher pressure in the sputtering chamber could cause the formation of larger grains on the fiber surfaces. The higher power used also generated larger grains on the fiber surfaces.

  11. Metal-organic Frameworks as A Tunable Platform for Designing Functional Molecular Materials

    PubMed Central

    Wang, Cheng; Liu, Demin

    2013-01-01

    Metal-organic frameworks (MOFs), also known as coordination polymers, represent an interesting class of crystalline molecular materials that are synthesized by combining metal-connecting points and bridging ligands. The modular nature of and mild conditions for MOF synthesis have permitted the rational structural design of numerous MOFs and the incorporation of various functionalities via constituent building blocks. The resulting designer MOFs have shown promise for applications in a number of areas, including gas storage/separation, nonlinear optics/ferroelectricity, catalysis, energy conversion/storage, chemical sensing, biomedical imaging, and drug delivery. The structure-property relationships of MOFs can also be readily established by taking advantage of the knowledge of their detailed atomic structures, which enables fine-tuning of their functionalities for desired applications. Through the combination of molecular synthesis and crystal engineering MOFs thus present an unprecedented opportunity for the rational and precise design of functional materials. PMID:23944646

  12. Design and production of functionalized biopolyesters by Methylobacterium extorquens ATCC 55366: Toward new tissue engineering materials

    NASA Astrophysics Data System (ADS)

    Hoefer, Heinrich Friedrich Philipp Till Nikolaus

    Vascular networks are required to support the formation and function of three-dimensional tissues. Biodegradable scaffolds are being considered in order to promote vascularization where natural regeneration of lost or destroyed vascular networks fails. Particularly; composite materials are expected to fulfill the complex demands of a patient's body to support wound healing. Microbial biopolyesters are being regarded as such second and third generation biomaterials. Methylobacterium extorquens is one of several microorganisms that should be considered for the production of advanced polyhydroxyalkanoates (PHAs). M. extorquens displays a distinct advantage in that it is able to utilize methanol as an inexpensive substrate for growth and biopolyester production. The design of functionalized PHAs, which would be made of both saturated short-chain-length (scl, C ? 5) and unsaturated medium-chain-length (mcl, 6 ? C ? 14) monomeric units, aimed at combining desirable material properties of inert scl/mcl-PHAs with those of functionalized mcl-PHAs. By independently inserting the phaC1 or the phaC2 gene from Pseudomonas fluorescens GK13, recombinant M. extorquens strains were obtained which were capable of producing PHAs containing C-C double bonds. A fermentation process was developed to obtain gram quantities of biopolyesters employing the recombinant M. extorquens ATCC 55366 strain which harbored the phaC2 gene of P. fluorescens GK13, the better one of the two strains at incorporating unsaturated monomeric units. The PHAs produced were found in a blend of scl-PHAs and functionalized scl/mcl-PHAs (4 ? C ? 6), which were the products of the native and of the recombinant PHA synthase, respectively. Thermo-mechanical analysis confirmed that the functionalized scl/mcl-PHAs exhibited the desirable material properties expected. This project contributed to current research on polyhydroxyalkanoates at different levels. The terminal double bonds of the functionalized scl/mcl-PHAs are amenable to chemical modifications and could be transformed into reactive functional groups for covalently linking other biomacromolecules. It is anticipated that these biopolyesters will be utilized as tissue engineering materials in the future, due to their functionality and thermo-mechanical properties. Keywords: biopolyesters, functionalized polyhydroxyalkanoates, Methylobacterium extorquens, genetic modification, fermentation in pilot-scale operators, material characterization, thermo-mechanical properties, tissue engineering

  13. Recent developments in 2D layered inorganic nanomaterials for sensing.

    PubMed

    Kannan, Padmanathan Karthick; Late, Dattatray J; Morgan, Hywel; Rout, Chandra Sekhar

    2015-08-28

    Two dimensional layered inorganic nanomaterials (2D-LINs) have recently attracted huge interest because of their unique thickness dependent physical and chemical properties and potential technological applications. The properties of these layered materials can be tuned via both physical and chemical processes. Some 2D layered inorganic nanomaterials like MoS2, WS2 and SnS2 have been recently developed and employed in various applications, including new sensors because of their layer-dependent electrical properties. This article presents a comprehensive overview of recent developments in the application of 2D layered inorganic nanomaterials as sensors. Some of the salient features of 2D materials for different sensing applications are discussed, including gas sensing, electrochemical sensing, SERS and biosensing, SERS sensing and photodetection. The working principles of the sensors are also discussed together with examples. PMID:26204797

  14. Recent developments in 2D layered inorganic nanomaterials for sensing

    NASA Astrophysics Data System (ADS)

    Kannan, Padmanathan Karthick; Late, Dattatray J.; Morgan, Hywel; Rout, Chandra Sekhar

    2015-08-01

    Two dimensional layered inorganic nanomaterials (2D-LINs) have recently attracted huge interest because of their unique thickness dependent physical and chemical properties and potential technological applications. The properties of these layered materials can be tuned via both physical and chemical processes. Some 2D layered inorganic nanomaterials like MoS2, WS2 and SnS2 have been recently developed and employed in various applications, including new sensors because of their layer-dependent electrical properties. This article presents a comprehensive overview of recent developments in the application of 2D layered inorganic nanomaterials as sensors. Some of the salient features of 2D materials for different sensing applications are discussed, including gas sensing, electrochemical sensing, SERS and biosensing, SERS sensing and photodetection. The working principles of the sensors are also discussed together with examples.

  15. Numerical Analysis of Stress Intensity Factors in Three-Dimensional Functionally Graded Materials

    SciTech Connect

    Guo Licheng; Wu Linzhi; Yu Hongjun

    2008-02-15

    In this paper, a finite element method based on nonhomogeneous elements is used to study crack problems in three-dimensional (3D) functionally graded materials (FGMs). Since the actual material properties at each integral point are employed in the integration during formation of the element stiffness matrix, each element can have nonhomogeneous material properties. By this method, the number of elements is reduced and the meshing effort for the structure is simplified. Therefore, the modeling process for numerical simulation of fracture behavior in 3D FGMs is greatly simplified. The crack front characteristics of Mode-I edge penetrable crack in 3D FGM specimens are studied under uniform tension loading. The influence of material nonhomogeneity constant and geometric parameters on the stress intensity factors (SIFs) of the 3D FGM specimens are investigated.

  16. Recent development in modeling and analysis of functionally graded materials and structures

    NASA Astrophysics Data System (ADS)

    Gupta, Ankit; Talha, Mohammad

    2015-11-01

    In this article, an extensive review related to the structural response of the functionally graded materials (FGMs) and structures have been presented. These are high technology materials developed by a group scientist in the late 1980's in Japan. The emphasis has been made here, to present the structural characteristics of FGMs plates/shells under thermo-electro-mechanical loadings under various boundary and environmental conditions. This paper also provides an overview of different fabrication procedures and the future research directions which is required to implement these materials in the design and analysis appropriately. The expected outcome of present review can be treated as milestone for future studies in the area of high technology materials and structures, and would be definitely advantageous for the researchers, scientists, and designers working in this field.

  17. Charting the complete elastic properties of inorganic crystalline compounds

    PubMed Central

    de Jong, Maarten; Chen, Wei; Angsten, Thomas; Jain, Anubhav; Notestine, Randy; Gamst, Anthony; Sluiter, Marcel; Krishna Ande, Chaitanya; van der Zwaag, Sybrand; Plata, Jose J; Toher, Cormac; Curtarolo, Stefano; Ceder, Gerbrand; Persson, Kristin A.; Asta, Mark

    2015-01-01

    The elastic constant tensor of an inorganic compound provides a complete description of the response of the material to external stresses in the elastic limit. It thus provides fundamental insight into the nature of the bonding in the material, and it is known to correlate with many mechanical properties. Despite the importance of the elastic constant tensor, it has been measured for a very small fraction of all known inorganic compounds, a situation that limits the ability of materials scientists to develop new materials with targeted mechanical responses. To address this deficiency, we present here the largest database of calculated elastic properties for inorganic compounds to date. The database currently contains full elastic information for 1,181 inorganic compounds, and this number is growing steadily. The methods used to develop the database are described, as are results of tests that establish the accuracy of the data. In addition, we document the database format and describe the different ways it can be accessed and analyzed in efforts related to materials discovery and design. PMID:25984348

  18. Integrated Micro/nanoengineered Functional Biomaterials for Cell Mechanics and Mechanobiology: A Materials Perspective

    PubMed Central

    Shao, Yue

    2014-01-01

    The rapid development of micro/nanoengineered functional biomaterials in the last two decades has empowered materials scientists and bioengineers to precisely control different aspects of the in vitro cell microenvironment. Following a philosophy of reductionism, many studies using synthetic functional biomaterials have revealed instructive roles of individual extracellular biophysical and biochemical cues in regulating cellular behaviors. Development of integrated micro/nanoengineered functional biomaterials to study complex and emergent biological phenomena has also thrived rapidly in recent years, revealing adaptive and integrated cellular behaviors closely relevant to human physiological and pathological conditions. Working at the interface between materials science and engineering, biology, and medicine, we are now at the beginning of a great exploration using micro/nanoengineered functional biomaterials for both fundamental biology study and clinical and biomedical applications such as regenerative medicine and drug screening. In this review, we present an overview of state of the art micro/nanoengineered functional biomaterials that can control precisely individual aspects of cell-microenvironment interactions and highlight them as well-controlled platforms for mechanistic studies of mechano-sensitive and -responsive cellular behaviors and integrative biology research. We also discuss the recent exciting trend where micro/nanoengineered biomaterials are integrated into miniaturized biological and biomimetic systems for dynamic multiparametric microenvironmental control of emergent and integrated cellular behaviors. The impact of integrated micro/nanoengineered functional biomaterials for future in vitro studies of regenerative medicine, cell biology, as well as human development and disease models are discussed. PMID:24339188

  19. Sulfur-Containing Organic-Inorganic Hybrid Gel Compositions and Aerogels

    NASA Technical Reports Server (NTRS)

    Evans, Owen R. (Inventor); Dong, Wenting (Inventor); Deshpande, Kiranmayi (Inventor)

    2015-01-01

    Methods and materials are described for preparing organic-inorganic hybrid gel compositions where a sulfur-containing cross-linking agent covalently links the organic and inorganic components. The gel compositions are further dried to provide porous gel compositions and aerogels. The mechanical and thermal properties of the dried gel compositions are also disclosed.

  20. Report of the Polymer Core Course Committee: Inclusion of Polymer Topics into Undergraduate Inorganic Chemistry Courses.

    ERIC Educational Resources Information Center

    Miller, Norman E.; And Others

    1984-01-01

    Suggests polymer topics for study in inorganic chemistry courses. Commercial materials (including list of inorganic compounds utilized in polymer industry), anchored metal catalysis, polymers modified or formed by coordination, polysiloxanes, phosphazene or phosphonitrilic halide polymers, and hetergeneous polymerization catalysts are considered.…

  1. Graphene-based hybrid structures combined with functional materials of ferroelectrics and semiconductors

    NASA Astrophysics Data System (ADS)

    Jie, Wenjing; Hao, Jianhua

    2014-05-01

    Fundamental studies and applications of 2-dimensional (2D) graphene may be deepened and broadened via combining graphene sheets with various functional materials, which have been extended from the traditional insulator of SiO2 to a versatile range of dielectrics, semiconductors and metals, as well as organic compounds. Among them, ferroelectric materials have received much attention due to their unique ferroelectric polarization. As a result, many attractive characteristics can be shown in graphene/ferroelectric hybrid systems. On the other hand, graphene can be integrated with conventional semiconductors and some newly-discovered 2D layered materials to form distinct Schottky junctions, yielding fascinating behaviours and exhibiting the potential for various applications in future functional devices. This review article is an attempt to illustrate the most recent progress in the fabrication, operation principle, characterization, and promising applications of graphene-based hybrid structures combined with various functional materials, ranging from ferroelectrics to semiconductors. We focus on mechanically exfoliated and chemical-vapor-deposited graphene sheets integrated in numerous advanced devices. Some typical hybrid structures have been highlighted, aiming at potential applications in non-volatile memories, transparent flexible electrodes, solar cells, photodetectors, and so on.

  2. Cyclodextrin-functionalized polyethylene and polypropylene as biocompatible materials for diclofenac delivery.

    PubMed

    Nava-Ortíz, Cesar A B; Alvarez-Lorenzo, Carmen; Bucio, Emilio; Concheiro, Angel; Burillo, Guillermina

    2009-12-01

    Polyethylene (PE) and polypropylene (PP) were surface functionalized with beta-cyclodextrin (beta-CD) and hydroxypropyl-beta-cyclodextrin (HP-beta-CD) with the aim of providing PE and PP with the capability of behaving as drug delivery systems. Functionalization was carried out according to a two-step procedure: (i) glycidyl methacrylate (GMA) was grafted by means of gamma radiation and (ii) the epoxy groups of GMA reacted with the hydroxyl groups of CDs forming ether bonds. For a fix radiation dose and GMA concentration, grafting yield (ranging from 1 to 100 micromol GMA cm(-2)) depended on the time during which the preirradiated PE and PP films and slabs were immersed in the GMA solution. CD grafting (from 0.013 to 0.734 micromol cm(-2)) was confirmed by infrared analysis, DSC and the organic compound approach (using 3-methylbenzoic acid as a probe). Functionalization with CDs rendered as highly cytocompatible materials as the starting ones, did not cause relevant changes in the water contact angle and the friction coefficient of PE and PP, but remarkably improved their capability to uptake diclofenac through formation of inclusion complexes with the CDs. Furthermore, the functionalized materials released the drug for 1 h, which could be useful for management of initial pain, inflammation at the insertion site as well as adhesion of certain microorganisms if these materials are used as medicated medical devices. PMID:19716868

  3. Inorganic nitrogen transformations within permeable carbonate sands

    NASA Astrophysics Data System (ADS)

    Erler, Dirk V.; Santos, Isaac R.; Eyre, Bradley D.

    2014-04-01

    A combination of in-situ push pull tests and a flow through reactor trial were used to quantify the inorganic nitrogen sinks in the permeable carbonate sands of a tropical coral cay (Heron Island - Great Barrier Reef). Addition of dissolved inorganic nitrogen (DIN in the form of nitrate - NO3-, and ammonium - NH4+) directly into sediment porewater resulted in uptake of up to 97% and 60% of added DIN respectively. The initial push pull experiment qualitatively showed that dissimilatory nitrate reduction to ammonia (DNRA), denitrification and nitrification were all active in the sediments. A flow through reactor experiment provided a more detailed approach to quantify these processes and showed that both denitrification and DNRA occurred within the sands at rates of 7.3 and 5.5 ?mol N cm-3 d-1, respectively. Unexpectedly the addition of labile organic material (fresh coral spawn) to the permeable sands did not result in the release of DIN from the reactors, on the contrary it resulted in the increased uptake of both NO3- and NH4+. This was most likely because of the stimulated N uptake associated with the addition of high C:N coral spawn material. The bulk of NH4+ produced via DNRA was found to be adsorbed to sediments within the reactor and was not released with the outlet water. A mass balance over the entire experimental period showed that more inorganic N was retained within the sediments than lost as gaseous products. Our results point to permeable carbonate sands acting as reservoirs of N under the influence of advective flow, even during sudden enrichment periods such as those following coral mass spawning. This implies that permeable carbonate sands may help to buffer coral reefs during periods of extreme oligotrophy.

  4. Carbon-Based Nanomaterials: Multi-Functional Materials for Biomedical Engineering

    PubMed Central

    Cha, Chaenyung; Shin, Su Ryon; Annabi, Nasim; Dokmeci, Mehmet R.; Khademhosseini, Ali

    2013-01-01

    Functional carbon-based nanomaterials (CBNs) have become important due to their unique combinations of chemical and physical properties (i.e., thermal and electrical conductivity, high mechanical strength, and optical properties), extensive research efforts are being made to utilize these materials for various industrial applications, such as high-strength materials and electronics. These advantageous properties of CBNs are also actively investigated in several areas of biomedical engineering. This Perspective highlights different types of carbon-based nanomaterials currently used in biomedical applications. PMID:23560817

  5. Functionally gradient material for membrane reactors to convert methane gas into value-added products

    DOEpatents

    Balachandran, U.; Dusek, J.T.; Kleefisch, M.S.; Kobylinski, T.P.

    1996-11-12

    A functionally gradient material for a membrane reactor for converting methane gas into value-added-products includes an outer tube of perovskite, which contacts air; an inner tube which contacts methane gas, of zirconium oxide, and a bonding layer between the perovskite and zirconium oxide layers. The bonding layer has one or more layers of a mixture of perovskite and zirconium oxide, with the layers transitioning from an excess of perovskite to an excess of zirconium oxide. The transition layers match thermal expansion coefficients and other physical properties between the two different materials. 7 figs.

  6. Functionally gradient material for membrane reactors to convert methane gas into value-added products

    DOEpatents

    Balachandran, Uthamalingam (Hinsdale, IL); Dusek, Joseph T. (Lombard, IL); Kleefisch, Mark S. (Napersville, IL); Kobylinski, Thadeus P. (Lisle, IL)

    1996-01-01

    A functionally gradient material for a membrane reactor for converting methane gas into value-added-products includes an outer tube of perovskite, which contacts air; an inner tube which contacts methane gas, of zirconium oxide, and a bonding layer between the perovskite and zirconium oxide layers. The bonding layer has one or more layers of a mixture of perovskite and zirconium oxide, with the layers transitioning from an excess of perovskite to an excess of zirconium oxide. The transition layers match thermal expansion coefficients and other physical properties between the two different materials.

  7. A study of crack in functionally graded material under dynamic loading

    SciTech Connect

    Nakagaki, Michihiko; Sasaki, Hiroyuki; Hagihara, Seiya

    1995-11-01

    The paper addresses a numerical treatment of a fracture occurring in the functionally graded materials (FGM) under a dynamic load. The FGM is composed of a titanium alloy as an inclusion and zirconia as the matrix, where a generation of microcracks is considered to occur in the ceramic phase of the high stressed area. A spherical grain model is used to describe thee elastic constitutive law for the FGM composite, in which the nonlinear effects due to the microcracking are accounted for. The most appropriate fracture parameter, T*, is used to assess the crack-tip severity in the highly inhomogeneous materials such as the present.

  8. Phase instability in ZrO{sub 2}{endash}NiAl functionally graded materials

    SciTech Connect

    He, Y.; Subramanian, V.; Lannutti, J.J.

    1997-10-01

    Sedimentation in organic solvents was followed by hot-pressing to produce 2 mole{percent} yttria stabilized zirconia-NiAl functionally graded materials (FGM{close_quote}s). These FGM{close_quote}s were better able to accommodate high levels of residual stress than alumina-NiAl FGM{close_quote}s; this is possibly due to enhanced tetragonal phase retention. However, we found that the zirconia layer in these FGM{close_quote}s subsequently experiences room temperature transformation of t-ZrO{sub 2} to m-ZrO{sub 2}. {copyright} {ital 1997 Materials Research Society.}

  9. Molecular Engineering of Functional Materials for Energy and Opto-Electronic Applications.

    PubMed

    Gao, Peng; Domanski, Konrad; Konrad, Domanski; Aghazada, Sadig; Rakstys, Kasparas; Paek, Sanghyun; Nazeeruddin, Mohammad Khaja

    2015-01-01

    This review presents an overview of the dedicated research directions of the Group for Molecular Engineering of Functional Materials (GMF). This includes molecular engineering aspects of sensitizers constructed from ruthenium complexes, organic molecules, porphyrins and phthalocyanines. Manipulation of organometal trihalide perovskites, and charge transporting materials for high performance perovskite solar cells and photo-detectors are also described. Controlling phosphorescence color, and quantum yields in iridium complexes by tailoring ligands for organic light emitting diodes are demonstrated. Efficient reduction of CO(2) to CO using molecular catalyst on a protected Cu(2)O photocathode, and cost-effective water-splitting cell using a high efficiency perovskite solar cell are presented. PMID:26507343

  10. Diversity and Periodicity: An Inorganic Chemistry Module. Teacher's Guide.

    ERIC Educational Resources Information Center

    Huheey, James; Sandoval, Amado

    This teacher's guide is designed to provide science teachers with the necessary guidance and suggestions for teaching inorganic chemistry. The material in this book can be integrated with the other modules in a sequence that helps students to see that chemistry is a unified science. Contents include: (1) "Periodicity: A Chemical Calendar"; (2)…

  11. Hybrid Organic-Inorganic Perovskites (HOIPs): Opportunities and Challenges.

    PubMed

    Berry, Joseph; Buonassisi, Tonio; Egger, David A; Hodes, Gary; Kronik, Leeor; Loo, Yueh-Lin; Lubomirsky, Igor; Marder, Seth R; Mastai, Yitzhak; Miller, Joel S; Mitzi, David B; Paz, Yaron; Rappe, Andrew M; Riess, Ilan; Rybtchinski, Boris; Stafsudd, Oscar; Stevanovic, Vladan; Toney, Michael F; Zitoun, David; Kahn, Antoine; Ginley, David; Cahen, David

    2015-09-16

    The conclusions reached by a diverse group of scientists who attended an intense 2-day workshop on hybrid organic-inorganic perovskites are presented, including their thoughts on the most burning fundamental and practical questions regarding this unique class of materials, and their suggestions on various approaches to resolve these issues. PMID:26223962

  12. Natural frequencies of cracked functionally graded material plates by the extended finite element method

    E-print Network

    Natarajan, S; Bordas, S; Rabczuk, T; Kerfriden, P

    2011-01-01

    In this paper, the linear free flexural vibration of cracked functionally graded material plates is studied using the extended finite element method. A 4-noded quadrilateral plate bending element based on field and edge consistency requirement with 20 degrees of freedom per element is used for this study. The natural frequencies and mode shapes of simply supported and clamped square and rectangular plates are computed as a function of gradient index, crack length, crack orientation and crack location. The effect of thickness and influence of multiple cracks is also studied.

  13. Interfacial Coatings for Inorganic Composite Insulation Systems

    SciTech Connect

    Hooker, M. W.; Fabian, P. E.; Stewart, M. W.; Grandlienard, S. D.; Kano, K. S.

    2006-03-31

    Inorganic (ceramic) insulation materials are known to have good radiation resistance and desirable electrical and mechanical properties at cryogenic and elevated temperatures. In addition, ceramic materials can withstand the high-temperature reaction cycle used with Nb3Sn superconductor materials, allowing the insulation to be co-processed with the superconductor in a wind-and-react fabrication process. A critical aspect in the manufacture of ceramic-based insulation systems is the deposition of suitable fiber-coating materials that prevent chemical reaction of the fiber and matrix materials, and thus provide a compliant interface between the fiber and matrix, which minimizes the impact of brittle failure of the ceramic matrix. Ceramic insulation produced with CTD-FI-202 fiber interfaces have been found to exhibit very high shear and compressive strengths. However, this material is costly to produce. Thus, the goal of the present work is to evaluate alternative, lower-cost materials and processes. A variety of oxide and polyimide coatings were evaluated, and one commercially available polyimide coating has been shown to provide some improvement as compared to uncoated and de-sized S2 glass.

  14. Inorganic ion sorbents

    DOEpatents

    Teter, David M.; Brady, Patrick V.; Krumhansl, James L.

    2006-10-17

    A process and medium for decontamination of water containing anionic species including arsenic and chromium, wherein compounds comprising divalent and trivalent metal oxides and sulfides are used to form surface complexes with contaminants under pH conditions within the range of potable water. In one embodiment natural and synthetic spinels and spinel-like materials are used as the sorbent substance.

  15. Inorganic ion sorbent method

    DOEpatents

    Teter, David M. (Edgewood, NM); Brady, Patrick V. (Albuquerque, NM); Krumhansl, James L. (Albuquerque, NM)

    2007-07-17

    A process and medium for decontamination of water containing anionic species including arsenic and chromium, wherein compounds comprising divalent and trivalent metal oxides and sulfides are used to form surface complexes with contaminants under pH conditions within the range of potable water. In one embodiment natural and synthetic spinels and spinel-like materials are used as the sorbent substance.

  16. Fabrication and electrocatalytic application of functionalized nanoporous carbon material with different transition metal oxides

    NASA Astrophysics Data System (ADS)

    Samiee, L.; Shoghi, F.; Vinu, A.

    2013-01-01

    In the work presented here, an attempt is made to study the effect of functionalization with different transition metal oxides on the mesostructural properties as well as electrochemical behavior of Pt/nanoporous carbon supports. In this respect, the functionalized samples have been synthesized by using CMK-3 and metallocene as transition metal sources. The platinum catalysts (5 wt% Pt) obtained through a conventional wet impregnation method. All the materials have been characterized by XRD (low and high), N2 adsorption-desorption isotherms, high-resolution transmission electron microscopy, high-resolution field emission scanning electron, EDX mapping images and cyclic voltammetry (CV) and rotating disk electrode (RDE) techniques. The results showed that the mesostructural order has been destroyed by functionalization of CMK-3 with CoO, whereas it is not that much affected in NiO and CuO functionalized samples. EDX image mapping exhibited the good and uniform dispersion of functionalizing elements (Ni, Cu, Fe and Co), Pt in the carbon supports. Moreover, XRD studies revealed the formation of smaller platinum crystallite sizes in NiO and CuO functionalized samples in relative to other functionalized supports. Electrochemical measurements were performed using CV and RDE method. Kinetic analysis revealed an activity increases in the following order: CMK-3-NiO-Pt > CMK-3-CuO-Pt > CMK-3-CoO-Pt > CMK-3-Fe2O3-Pt which is showing of simultaneous effect of surface area and surface reactivity parameters.

  17. GEN IV MATERIALS HANDBOOK BETA RELEASE FOR STRUCTURAL AND FUNCTIONAL EVALUATION

    SciTech Connect

    Ren, Weiju; Luttrell, Claire

    2006-09-12

    Development of the Gen IV Materials Handbook is briefly summarized up to date. Current status of the Handbook website construction is described. The developed Handbook components and access control of the beta version are discussed for the present evaluation release. Detailed instructions and examples are given to provide guidance for evaluators to browse the constructed parts and use all the currently developed functionalities of the Handbook in evaluation.

  18. Method and apparatus for determination of mechanical properties of functionally-graded materials

    DOEpatents

    Giannakopoulos, Antonios E. (Somerville, MA); Suresh, Subra (Wellesley, MA)

    1999-01-01

    Techniques for the determination of mechanical properties of homogenous or functionally-graded materials from indentation testing are presented. The technique is applicable to indentation on the nano-scale through the macro-scale including the geological scale. The technique involves creating a predictive load/depth relationship for a sample, providing an experimental load/depth relationship, comparing the experimental data to the predictive data, and determining a physical characteristic from the comparison.

  19. PREFACE: 12th Russia/CIS/Baltic/Japan Symposium on Ferroelectricity and 9th International Conference on Functional Materials and Nanotechnologies (RCBJSF-2014-FM&NT)

    NASA Astrophysics Data System (ADS)

    Sternberg, Andris; Grinberga, Liga; Sarakovskis, Anatolijs; Rutkis, Martins

    2015-03-01

    The joint International Symposium RCBJSF-2014-FM&NT successfully has united two international events - 12th Russia/CIS/Baltic/Japan Symposium on Ferroelectricity (RCBJSF-12) and 9th International Conference Functional Materials and Nanotechnologies (FM&NT-2014). The RCBJSF symposium is a continuation of series of meetings on ferroelectricity, the first of which took place in Novosibirsk (USSR) in 1976. FM&NT conferences started in 2006 and have been organized by Institute of Solid State Physics, University of Latvia in Riga. In 2012 the International program committee decided to transform this conference into a traveling Baltic State conference and the FM&NT-2013 was organized by the Institute of Physics, University of Tartu, Estonia. In 2014 the joint international symposium RCBJSF-2014-FM&NT was organized by the Institute of Solid State Physics, University of Latvia and was part of Riga - 2014, the European Capital of Culture event. The purpose of the joint Symposium was to bring together scientists, students and high-level experts in solid state physics, materials science, engineering and related disciplines. The number of the registered participants from 26 countries was over 350. During the Symposium 128 high quality scientific talks (5 plenary, 42 invited, 81 oral) and over 215 posters were presented. All presentations were divided into 4 parallel sessions according to 4 main topics of the Symposium: Ferroelectricity, including ferroelectrics and multiferroics, pyroelectrics, piezoelectrics and actuators, integrated ferroelectrics, relaxors, phase transitions and critical phenomena. Multifunctional Materials, including theory, multiscale and multiphenomenal material modeling and simulation, advanced inorganic, organic and hybrid materials. Nanotechnologies, including progressive methods, technologies and design for production, investigation of nano- particles, composites, structures, thin films and coatings. Energy, including perspective materials and technologies for renewable and hydrogen energy, fuel cells, photovoltaics, LEDs, OLEDs. Based on these reports, 48 papers are included in this volume of IOP Conference Series: Materials Science and Engineering. Additional information about RCBJSF-2014-FM&NT is available at the homepage http://www.fmnt.lu.lv. The Organizing Committee would like to thank all the speakers, contributors, session chairs, referees and other involved staff for their efforts in making the RCBJSF-2014-FM&NT successful. Sincerely, organizers of the event Andris Sternberg Liga Grinberga Anatolijs Sarakovskis Martins Rutkis

  20. Low work function materials for microminiature energy conversion and recovery applications

    DOEpatents

    Zavadil, Kevin R.; Ruffner, Judith A.; King, Donald B.

    2003-05-13

    Low work function materials are disclosed together with methods for their manufacture and integration with electrodes used in thermionic conversion applications (specifically microminiature thermionic conversion applications). The materials include a mixed oxide system and metal in a compositionally modulated structure comprised of localized discontinuous structures of material that are deposited using techniques suited to IC manufacture, such as rf sputtering or CVD. The structures, which can include layers are then heated to coalescence yielding a thin film that is both durable and capable of electron emission under thermionic conversion conditions used for microminiature thermionic converters. Using the principles of the invention, thin film electrodes (emitters and collectors) required for microconverter technology are manufactured using a single process deposition so as to allow for full fabrication integration consistent with batch processing, and tailoring of emission/collection properties. In the preferred embodiment, the individual layers include mixed BaSrCaO, scandium oxide and tungsten.