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1

Crystallization and functionality of inorganic materials  

SciTech Connect

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.

Xue, Dongfeng, E-mail: dongfeng@ciac.jl.cn [State Key Laboratory of Rare Earth Resource Utilization, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, Changchun 130022 (China) [State Key Laboratory of Rare Earth Resource Utilization, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, Changchun 130022 (China); School of Chemical Engineering, Dalian University of Technology, Dalian 116024 (China); Li, Keyan [School of Chemical Engineering, Dalian University of Technology, Dalian 116024 (China)] [School of Chemical Engineering, Dalian University of Technology, Dalian 116024 (China); Liu, Jun [Key Laboratory of Low Dimensional Materials and Application Technology, Ministry of Education, Faculty of Materials, Optoelectronics and Physics, Xiangtan University, 411105 (China)] [Key Laboratory of Low Dimensional Materials and Application Technology, Ministry of Education, Faculty of Materials, Optoelectronics and Physics, Xiangtan University, 411105 (China); Sun, Congting; Chen, Kunfeng [State Key Laboratory of Rare Earth Resource Utilization, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, Changchun 130022 (China) [State Key Laboratory of Rare Earth Resource Utilization, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, Changchun 130022 (China); School of Chemical Engineering, Dalian University of Technology, Dalian 116024 (China)

2012-10-15

2

Preparation of Ce3+-Doped Inorganic-Organic Hybrid Materials Using Functionalized Silanes  

Microsoft Academic Search

Ce3+-doped, inorganic-organic hybrid monoliths were prepared from Si(OCH3)4, CH3 Si(OCH3)3, CeCl3 and various functionalized silanes (FSs) such as amino- (APTM), glycidyloxy- (GPTM), trifluoro- (TFTM) and chloro-(CPTM) silanes at 60°C by the sol-gel process. The functional groups of silane coupling agents coordinated with Ce3+ ions in the inorganic-organic materials. Ce3+-doped materials were transparent under the preparation conditions of FS\\/Ce3+ ratio of

M. Iwasaki; J. Kuraki; S. Ito

1998-01-01

3

Geological and Inorganic Materials.  

ERIC Educational Resources Information Center

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.…

Jackson, L. L.; And Others

1989-01-01

4

Inorganic polymer engineering materials  

SciTech Connect

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.

Stone, M.L.

1993-06-01

5

Inorganic fullerene-like material as additives to lubricants: structure–function relationship  

Microsoft Academic Search

Recently, inorganic fullerene-like (IF) supramolecules of metal dichalcogenide MX2 (M=Mo, W, etc.; X=S, Se), materials with structures closely related to (nested) carbon fullerenes and nanotubes have been synthesized. The main goal of the present work was to study the tribological properties of IF–WS2 in comparison to 2H–WS2 and MoS2 platelets over a wide range of loads and sliding velocities. The

L Rapoport; Y Feldman; M Homyonfer; H Cohen; J Sloan; J. L Hutchison; R Tenne

1999-01-01

6

Inorganic functional materials: optimization of properties by structural and compositional control.  

PubMed

A review is given of the strategies used to dope inorganic solids and the consequences for properties such as ionic and electronic conductivity. Doping mechanisms involve either substitution of foreign ions onto lattice sites, creation of vacancies on either cation or anion sites, or population of normally empty interstitial sites by either anions or cations. Mechanisms for charge compensation associated with aliovalent doping are reviewed and examples are given in the fields of solid state ionics and high-temperature superconductivity. The strategies used for targeting materials with new properties are reviewed, including a surprising number of cases where startling new properties are encountered in well-known materials. Specific examples discussed include MgB2 superconductor, Na beta-alumina sodium ion conductor, Ca12Al14O33 oxide ion conductor, LiCoMnO4 lithium battery cathode, doped Li4SiO4 tunable lithium ion conductor, and La-doped BaTiO3 ferroelectric, which can be either semiconducting or insulating. Examples are also given of a curious observation that extraordinary properties are often encountered in materials that are on the edge of stability, either structurally or compositionally or at the crossover between different property types. PMID:16900482

West, Anthony R

2006-01-01

7

Preface: Overview of the Forum on Functional Inorganic Materials P. Shiv Halasyamani*,  

E-print Network

show promise, but it remains an ongoing challenge to discover new high- materials. What exactly defines including the oxidation state, ion size, crystallographic order or disorder, coordination number, the change in polarization as a function of temperature. The effect was first observed over 2400 years ago

Poeppelmeier, Kenneth R.

8

Inorganic–organic hybrid materials based on functionalized silica and carbon: A comprehensive understanding toward the structural property and catalytic activity difference over mesoporous silica and carbon supports  

Microsoft Academic Search

Inorganic–organic hybrid materials based on functionalized silica and carbon were synthesized by anchoring molybdovanadophosphoric acid (H5[PMo10V2O40]·32.5H2O) onto amine-functionalized SBA-15, ethane-bridged SBA-15 and mesoporous carbon, respectively. Small angle X-ray diffraction, N2 sorption analysis, HRTEM, SEM, FT-IR, CP-MAS NMR were used to diagnose the mesoporous structure of inorganic–organic hybrid materials. The structural integrity of molybdovanadophosphoric acid has been found to be retained

Ankur Bordoloi; Nevin T. Mathew; F. Lefebvre; S. B. Halligudi

2008-01-01

9

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

E-print Network

electrons #12;UCSB Materials Colloquium 4/16/2010 1. Tricolor LEDs with no need for phosphors 2. UV LED;UCSB Materials Colloquium 4/16/2010 LEDs: Converting electricity to light (not heat !) holes np + RGB phosphors 3. Blue LED + yellow/orange phosphors Solid state lighting strategies #12;UCSB Materials

Akhmedov, Azer

10

Plasma chemistry for inorganic materials  

NASA Technical Reports Server (NTRS)

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.

Matsumoto, O.

1980-01-01

11

Fabrication and characterization of nanostructured titania films with integrated function from inorganic-organic hybrid materials.  

PubMed

Nanostructured titania films are of growing interest due to their application in future photovoltaic technologies. Therefore, a lot of effort has been put into the controlled fabrication and tailoring of titania nanostructures. The controlled sol-gel synthesis of titania, in particular in combination with block copolymer templates, is very promising because of its high control on the nanostructure, easy application and cheap processing possibilities. This tutorial review gives a short overview of the structural control of titania films gained by using templated sol-gel chemistry and shows how this approach is extended by the addition of further functionality to the films. Different expansions of the sol-gel templating are possible by the fabrication of gradient samples, by the addition of a homopolymer, by the combination with micro-fluidics and also by the application of novel precursors for low-temperature processing. Moreover, hierarchically structured titania films can be fabricated via the subsequent application of several sol-gel steps or via the inclusion of colloidal templates in a one-step process. Integrated function in the block copolymer used in the sol-gel synthesis allows for the fabrication of an integrated blocking layer or an integrated hole-conductor. Both approaches grant a one-step fabrication of two components of a working solar cell, which make them very promising towards a cheap solar cell production route. Looking to the complete solar cell, the top contact is also of great importance as it influences the function of the whole solar cell. Thus, the mechanisms acting in the top contact formation are also reviewed. For all these aspects, characterization techniques that allow for a structural investigation of nanostructures inside the active layers are important. Therefore, the characterization techniques that are used in real space as well as in reciprocal space are explained shortly as well. PMID:22415549

Rawolle, Monika; Niedermeier, Martin A; Kaune, Gunar; Perlich, Jan; Lellig, Philipp; Memesa, Mine; Cheng, Ya-Jun; Gutmann, Jochen S; Müller-Buschbaum, Peter

2012-08-01

12

Inorganic–Organic Hybrid Porous Materials  

Microsoft Academic Search

Hybrid materials are becoming increasingly important because of the possibility of combining inorganic, organic, and even\\u000a biological entities and functions in a well-defined host matrix.\\u000a \\u000a Soft chemistry-based processes (i.e., chemical pathways at low temperatures and pressures, from molecular, colloidal, or polymeric\\u000a precursors) clearly offer the most favourable paths towards hybrid materials. Especially the mild reaction conditions and\\u000a the high adaptability

Nicola Hüsing; Sarah Hartmann

13

Preparation and characterisation of an epoxy-functional inorganic–organic hybrid material system with phenyl side group for waveguiding applications  

Microsoft Academic Search

An epoxy-functional inorganic–organic hybrid material system for use in photonic waveguiding applications was synthesised by the sol–gel method. The influence of preparation process parameters such as composition and UV irradiation, on the properties of the deposited thin films was studied. Crack-free films with thickness up to 37 ?m were obtained from a single-step deposition process. A tunable refractive index, at 633 nm,

Shane O'Brien; Mehmet Çopuro?lu; Gabriel M. Crean

2007-01-01

14

Chemical design of solid inorganic materials  

Microsoft Academic Search

Newer strategies for the synthesis of inorganic solids have made a great impact on present-day materials chemistry. In this article, typical case studies of synthesis involving new methods and soft chemical routes are discussed besides recent results from nebulized spray pyrolysis and synthesis of nanoscale metal and alloy particles. Introduct ion Strategies for the synthesis of inorganic solids are being

C. N. R. Rao

1997-01-01

15

Porphyrin photochemistry in inorganic\\/organic hybrid materials: Clays, layered semiconductors, nanotubes, and mesoporous materials  

Microsoft Academic Search

Porphyrin derivatives are known as useful functional dyes. Porphyrin derivatives exhibit various properties in complexes with inorganic host materials that are much different from those in homogeneous solutions. In this paper, the structure and photochemical properties of porphyrins in inorganic host materials such as clays, layered semiconductors, nanotubes, and mesoporous materials are described. The photochemical properties, including the absorption properties

Shinsuke Takagi; Miharu Eguchi; Donald A. Tryk; Haruo Inoue

2006-01-01

16

Inorganic-organic materials incorporating alumoxane nanoparticles  

NASA Astrophysics Data System (ADS)

Chemically functionalized alumina nanoparticles (carboxylate-alumoxanes) are used as the inorganic component of a new class of inorganic-organic material. Lysine- or para-hydroxybenzoic acid-derivatized alumoxanes are prepared from the reaction of boehmite, [Al(O)(OH)]n, with the appropriate carboxylic acid. The peripheral hydroxides and amines of these alumoxanes react directly with DER 332 epoxide to form a hybrid material, or in the presence of a resin and hardener system, to form a composite material. Solid state NMR spectroscopy demonstrates that the alumoxanes are chemically bound to the resin matrix. The properties and cure times of the alumoxane materials are distinct from both the pure resins and from a physical blend of the resins with traditional fillers. A significant increase in thermal stability and tensile strength is observed for the resin systems. In order to produce molecular coupling layers, epoxides cross-linked with self-assembled monolayers (SAMs) grown on the native oxide of aluminum thin films on silicon substrates have been investigated. Specifically, SAMs have been formed by the attachment of different carboxylic acids. In order to investigate the cross-linking reaction between carboxylate monolayers and an epoxide, grown monolayers were reacted with a mono-epoxy resin. In addition to these surface materials, aluminum oxide surfaces supporting carboxylate monolayers were reacted in pairs with DER 332 to form a structural adhesive. These materials have been characterized variously by SEM, AFM, XPS, EDX, and contact angle measurements. The particle size dependence on pH of a series of alumoxanes was investigated. For each of the alumoxanes, PCS particle size measurements were obtained as a function of pH. In all cases, particle size control was afforded by variations in pH. Finally, crystal structures of several model compounds were determined by X-ray crystallography, and shown to form either sheets of dimers or tetrameric units. Through a review of structures found in the Cambridge Crystallographic Database, compounds of the type X-CH(OH)CH 2NH-Y were investigated. The results of this study lead to a generalized approach for predicting the packing motifs of racemic mixtures in polar space groups.

Vogelson, Cullen Taylor

17

Combinatorial synthesis of inorganic or composite materials  

DOEpatents

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.

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

18

Combinatorial screening of inorganic and organometallic materials  

DOEpatents

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.

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

2002-01-01

19

Inorganic polymers and materials. Final report  

SciTech Connect

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.

Sneddon, Larry G.

2001-01-01

20

Inorganic-organic hybrid material for lithography  

Microsoft Academic Search

Tetraethoxyorthosilicate and methacryloxypropyl trimethoxy silane are used to form inorganic and organic networks, respectively. Photosensitive agent is added to initiate free-radical cross-linking polymerization of unsaturated carbon bonds and thus makes the material act as a negative tone photoresist. Developed in dilute base solution, micro- optical element, such as lenses and gratings, were fabricated by contact with UV-exposure. Shrinkage effect is

Lin Pang; Yingbai Yan; Guofan Jin; Minxian Wu

2000-01-01

21

Design of Inorganic and Inorganic-Organic Hybrid Materials by Sol-Gel Processing – From Nanostructures to Hierarchical Networks  

Microsoft Academic Search

The preparation of porous hierarchical architectures that have structural features spanning from the nanometer to micrometer\\u000a and even larger dimensions which in addition exhibit defined functionalities is one of today’s challenges in materials chemistry.\\u000a Sol-gel chemistry is a versatile tool for the formation of inorganic as well as inorganic-organic hybrid materials. Controlled\\u000a hydrolysis and condensation reactions of (organo)alkoxysilanes allow the

Nicola Hüsing

22

Combinatorial solid-state chemistry of inorganic materials  

NASA Astrophysics Data System (ADS)

Throughout history, scientists and engineers have relied on the slow and serendipitous trial-and-error process for discovering and developing new materials. In contrast, an emerging theme in modern materials science is the notion of intelligent design of materials. Pioneered by the pharmaceutical industry and adapted for the purposes of materials science and engineering, the combinatorial approach represents a watershed in the process of accelerated discovery, development and optimization of materials. To survey large compositional landscapes rapidly, thousands of compositionally varying samples may be synthesized, processed and screened in a single experiment. Recent developments have been aided by innovative rapid characterization tools, and by advanced materials synthesis techniques such as laser molecular beam epitaxy which can be used to perform parallel-processed design and control of materials down to the atomic scale. Here we review the fast-growing field of combinatorial materials science, with an emphasis on inorganic functional materials.

Koinuma, Hideomi; Takeuchi, Ichiro

2004-07-01

23

Effect of preparation conditions on the thermal stability of an epoxy-functional inorganic–organic hybrid material system doped with Zr  

Microsoft Academic Search

An inorganic–organic hybrid material system consisting of (3-glycidyloxypropyl)trimethoxysilane, dimethyldimethoxysilane and zirconium(IV) n-propoxide was prepared by the sol–gel method. The influence of processing parameters including Zr content, UV irradiation and sol ageing on the thermal stability of the resultant thin films was characterised by thermogravimetry. It was demonstrated that the crosslinking of epoxy groups in the structure was the primary reason

Mehmet Çopuro?lu; Shane O’Brien; Gabriel M. Crean

2007-01-01

24

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

NASA Astrophysics Data System (ADS)

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.

Ziegler, Christopher R.

25

Characteristics of colored inorganic–organic hybrid materials  

Microsoft Academic Search

Inorganic–organic hybrid glasses are relatively new nanometric materials of Ormosil’s group (organic modified silicates). There co-existence, on a molecular scale, exists between inorganic structures in the form of silica-oxide network and organic structures based on carbon links. Properties of these materials are intermediate between those of inorganic glasses (hardness, chemical and thermal resistance) and organic polymers (low temperature of obtaining,

K. Wojtach; M. Laczka; K. Cholewakowalska; Z. Olejniczak; J. Sokolowska

2007-01-01

26

Porous inorganic–organic hybrid material by oxygen plasma treatment  

Microsoft Academic Search

In this paper, we present the pore formation on inorganic–organic hybrid material, ORMOCER©, by reactive ion etching. ORMOCERs are composed of inorganic backbone where organic side groups are attached by cross-linking. Etching of ORMOCER in oxygen plasma generates porous materials with different pore sizes depending on the etching parameters. In addition to planar films, this pore formation process is applicable

Susanna Aura; Ville Jokinen; Mikko Laitinen; Timo Sajavaara; Sami Franssila

2011-01-01

27

Inorganic polymers and materials. Final report  

Microsoft Academic Search

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

Sneddon; Larry G

2001-01-01

28

ORMOCER®S – Inorganic-Organic Hybrid Materials for e\\/o-Interconnection-Technology  

Microsoft Academic Search

Hybrid inorganic-organic polymers (ORMOCER®s) have been developed and tested for evaluation in optical and electrical interconnection technology. The photopatternable materials with negative resist behaviour are composed of inorganic oxidic structures cross-linked or substituted by organic groups. They are prepared from organosilane precursors by sol-gel-processing in combination with organic crosslinking of polymerizable organic functions. As a result of these functionalities the

M. Popall; A. Dabek; M. E. Robertsson; S. Valizadeh; O. J. Hagel; R. Buestrich; R. Nagel; L. Cergel; D. Lambert; M. Schaub

2000-01-01

29

Cavitational synthesis of nanostructured inorganic materials for enhanced heterogeneous catalysis  

NASA Astrophysics Data System (ADS)

The synthesis of nanostructured inorganic materials by hydrodynamic cavitation processing was investigated. The goal of this work was to develop a general synthesis technique for nanostructured materials with a control over crystallite size in the 1--20 nm range. Materials with crystallite sizes in this range have shown enhanced catalytic activity compared to materials with larger crystallite sizes. Several supported and unsupported inorganic materials were studied to understand the effects of cavitation on crystallite size. Cavitation processing of calcium fluoride resulted in more spherical particles, attached to one another by melted necks. This work produced the first evidence of shock wave heating of nanostructured materials by hydrodynamic cavitation processing. Hydrodynamic cavitation synthesis of various catalytic support materials indicated that their phase composition and purity could be controlled by adjustment of the processing parameters. Zirconia/alumina supports synthesized using hydro-dynamic cavitation and calcined to 1368 K retained a high purity cubic zirconia phase, whereas classically prepared samples showed a phase transformation to monoclinic zirconia. Similarly, the synthesis of alumina resulted in materials with varying Bohmite and Bayerite contents as a function of the process parameters. High temperature calcination resulted in stable alumina supports with varying amounts of delta-, and theta-alumina. Synthesis studies of palladium and silver showed modest variations in crystallite size as a function of cavitation process parameters. Calcination resulted in larger grain materials, indicating a disappearance of intergrain boundaries. Based on these results, a new synthesis method was studied involving controlled agglomeration of small silver crystallites by hydrodynamic cavitation processing, followed by deposition on alumina. The optimal pH, concentration, and processing time for controlling the silver crystallite size in the cavitation equipment were determined using a statistical design of experiments approach. Three series of alumina supported silver catalysts were prepared, with silver weight loadings of 1%, 2%, and 5%. Variation of cavitation processing time between 1--64 min allowed the systematic control of silver crystallite size in the range of 3--19 nm. The preferred oxidation of CO in hydrogen (PROX) was chosen as a catalytic test reaction, because of its increasing importance for fuel cell applications. It was found that the catalytic activity was significantly increased for silver crystallite sizes below 5 nm. This work is the first experimental evidence of independent crystallite size control by hydrodynamic cavitation for alumina supported silver catalysts. The synthesis method involving controlled agglomeration and calcination is a general synthesis procedure that can be used to synthesize a wide range of novel catalysts and advanced materials.

Krausz, Ivo Michael

30

Development of an inorganic additive to active materials of lead acid batteries  

Microsoft Academic Search

Summary form only given as follows. The most prominent type of additives that have been used over the years for lead acid batteries are those that impact the functioning of the active materials. Whereas the positive active material (PAM) is usually additive free the negative active material (NAM) is usually modified by a variety of additives, both organic and inorganic.

A. L. Ferreira; G. Zguris

2002-01-01

31

Soft templating strategies for the synthesis of mesoporous materials: inorganic, organic-inorganic hybrid and purely organic solids.  

PubMed

With the discovery of MCM-41 by Mobil researchers in 1992 the journey of the research on mesoporous materials started and in the 21st century this area of scientific investigation have extended into numerous branches, many of which contribute significantly in emerging areas like catalysis, energy, environment and biomedical research. As a consequence thousands of publications came out in large varieties of national and international journals. In this review, we have tried to summarize the published works on various synthetic pathways and formation mechanisms of different mesoporous materials viz. inorganic, organic-inorganic hybrid and purely organic solids via soft templating pathways. Generation of nanoscale porosity in a solid material usually requires participation of organic template (more specifically surfactants and their supramolecular assemblies) called structure-directing agent (SDA) in the bottom-up chemical reaction process. Different techniques employed for the syntheses of inorganic mesoporous solids, like silicas, metal doped silicas, transition and non-transition metal oxides, mixed oxides, metallophosphates, organic-inorganic hybrids as well as purely organic mesoporous materials like carbons, polymers etc. using surfactants are depicted schematically and elaborately in this paper. Moreover, some of the frontline applications of these mesoporous solids, which are directly related to their functionality, composition and surface properties are discussed at the appropriate places. PMID:23337774

Pal, Nabanita; Bhaumik, Asim

2013-03-01

32

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

PubMed

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

Wang, Hailiang; Dai, Hongjie

2013-04-01

33

Investigation of novel inorganic resist materials for EUV lithography  

NASA Astrophysics Data System (ADS)

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.

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

2014-04-01

34

Inorganic-organic electrolyte materials for energy applications  

Microsoft Academic Search

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,

Shih-To Fei

2010-01-01

35

Design and properties of functional hybrid organic-inorganic membranes for fuel cells.  

PubMed

This critical review presents a discussion on the major advances in the field of organic-inorganic hybrid membranes for fuel cells application. The hybrid organic-inorganic approach, when the organic part is not conductive, reproduces to some extent the behavior of Nafion where discrete hydrophilic and hydrophilic domains are homogeneously distributed. A large variety of proton conducting or non conducting polymers can be combined with various functionalized, inorganic mesostructured particles or an inorganic network in order to achieve high proton conductivity, and good mechanical and chemical properties. The tuning of the interface between these two components and the control over chemical and processing conditions are the key parameters in fabricating these hybrid organic-inorganic membranes with a high degree of reproducibility. This dynamic coupling between chemistry and processing requires the extensive use and development of complementary ex situ measurements with in situ characterization techniques, following in real time the molecular precursor solutions to the formation of the final hybrid organic-inorganic membranes. These membranes combine the intrinsic physical and chemical properties of both the inorganic and organic components. The development of the sol-gel chemistry allows a fine tuning of the inorganic network, which exhibits acid-based functionalized pores (-SO(3)H, -PO(3)H(2), -COOH), tunable pore size and connectivity, high surface area and accessibility. As such, these hybrid membranes containing inorganic materials are a promising family for controlling conductivity, mechanical and chemical properties (349 references). PMID:21218233

Laberty-Robert, C; Vallé, K; Pereira, F; Sanchez, C

2011-02-01

36

Thermal/chemical degradation of inorganic membrane materials  

SciTech Connect

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.

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

1995-12-01

37

Inorganic–organic hybrid materials for application in optical devices  

Microsoft Academic Search

Integrated passive and active optical devices are the key components in current and future data transfer technologies. In order to fulfill future requirements in miniaturization for diffractive, refractive and integrated optical devices, new materials with higher thermal stability and a better compatibility to processing techniques used in conventional semiconductor devices production are needed. Inorganic–organic hybrid polymers (ORMOCER®s) produced at fairly

R. Houbertz; G. Domann; C. Cronauer; A. Schmitt; H. Martin; J.-U. Park; L. Fröhlich; R. Buestrich; M. Popall; U. Streppel; P. Dannberg; C. Wächter; A. Bräuer

2003-01-01

38

Novel organic-inorganic hybrid mesoporous materials and nanocomposites  

NASA Astrophysics Data System (ADS)

Organic-inorganic hybrid mesoporous materials have been prepared successfully via the nonsurfactant templated sol-gel pathway using dibenzoyl-L-tartaric acid (DBTA) as the templating compound. Styrene and methyl methacrylate polymers have been incorporated into the mesoporous silica matrix on the molecular level. The synthetic conditions have been systematically studied and optimized. Titania based mesoporous materials have also been made using nonionic polyethylene glycol surfactant as the pore forming or structure-directing agent. In all of the above mesoporous materials, pore structures have been studied in detail by Transmission Electron Microscopy (TEM), X-ray diffraction and Brunauer-Emmett-Teller (BET) characterizations. The relationship between the template concentration and the pore parameters has been established. This nonsurfactant templated pathway possesses many advantages over the known surfactant approaches such as low cost, environment friendly and biocompatability. To overcome the drawback of nonsurfactant templated mesoporous materials that lack a well ordered pore structure, a flow induced synthesis has been attempted to orientate the sol-gel solution in order to obtain aligned pore structures. The versatility of this nonsurfactant templated pathway can even be extended to the making of organic-inorganic hybrid nanocomposite materials. On the basis of this approach, polymer-silica nanocomposite materials have been prepared using a polymerizable template. It is shown that the organic monomer such as hydroxyethyl methacrylate can act as a template in making nanoporous silica materials and then be further polymerized through a post synthesis technique. The properties and morphology of this new material have been studied by Differential Scanning Calorimetry (DSC), Scanning Electron Microscopy (SEM) and Infrared Absorption Spectroscopy (FTIR). Electroactive organic-inorganic hybrid materials have also been synthesized via the sol-gel process. A coupling agent was used to covalently bond the organic and inorganic species. The morphology and conductivity of the products have been investigated.

Feng, Qiuwei

39

Combinatorial Screening Of Inorganic And Organometallic Materials  

DOEpatents

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.

Li, Yi (Miami, FL), Li, Jing (Miami, FL), Britton, Ted W. (Sunrise, FL)

2002-06-25

40

Effect of preparation conditions on the thermal stability of an epoxy-functional inorganic–organic hybrid material system with phenyl side group  

Microsoft Academic Search

A hybrid material system consisting of (3-glycidyloxypropyl)trimethoxysilane and dimethyldimethoxysilane as matrix materials and diphenyldimethoxysilane (DPDMS) as both a matrix material and a potential thermal stabiliser by the sol–gel method. A detailed thermogravimetric analysis study of the influence of processing parameters, including DPDMS content, UV irradiation and sol ageing, on the thermal stability of the resultant thin films was presented. FT-IR

Mehmet Çopuro?lu; Shane O'Brien; Gabriel M. Crean

2006-01-01

41

Slurry Nebulization in Plasmas for Analysis of Inorganic Materials  

Microsoft Academic Search

This review summarizes and discusses the preparation of slurries for analysis of inorganic materials by inductively coupled plasma optical emission spectrometry (ICP?OES) and inductively coupled plasma mass spectrometry (ICP?MS). Details about the grinding step for slurry preparation, the stabilization of slurries, and the calibration strategies are critically discussed. Typical applications described in the literature and the state?of?the?art including advantages and

Mirian C. Santos; Joaquim A. Nóbrega

2006-01-01

42

Mesoscopic 2-D ordering of inorganic\\/organic hybrid materials  

Microsoft Academic Search

Organic–inorganic hybrid materials with micronsized (i.e., mesoscopic) network structures are expected to have interesting properties and applications in various fields, such as separation, catalysis, biomineralization, or quantum optics. Here a new method is introduced to produce thin films of two-dimensionally ordered honeycomb structures. Casting a chloroform solution of a mixture of organic amphiphiles with metal acetylacetonates or -alkoxides at high

O Karthaus; X Cieren; N Maruyama; M Shimomura

1999-01-01

43

Interactions between lipid bilayers and inorganic material surfaces  

NASA Astrophysics Data System (ADS)

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.

Mager, Morgan Douglas

44

Porous inorganic-organic hybrid material by oxygen plasma treatment  

NASA Astrophysics Data System (ADS)

In this paper, we present the pore formation on inorganic-organic hybrid material, ORMOCER©, by reactive ion etching. ORMOCERs are composed of inorganic backbone where organic side groups are attached by cross-linking. Etching of ORMOCER in oxygen plasma generates porous materials with different pore sizes depending on the etching parameters. In addition to planar films, this pore formation process is applicable to micro and nanostructures. Characteristics of porous materials are evaluated by contact angle measurement, scanning electron microscopy, Fourier transform infrared-attenuated total reflectance spectroscopy, time-of-flight elastic recoil detection analysis and Rutherford backscattering spectrometry. Based on these analyses, it can be concluded that carbon is depleted in the plasma process and oxygen plasma converts the surface of the hybrid film to a more SiO2-like material. Area selective pore formation is also possible by using a metallic etch mask. The porous material is stable enough to allow further processing, e.g. sputtering, plasma-enhanced chemical vapor deposition and atomic layer thin film deposition. This method may thus be used in different applications in fluidics, optics and elsewhere in micro and nanotechnology.

Aura, Susanna; Jokinen, Ville; Laitinen, Mikko; Sajavaara, Timo; Franssila, Sami

2011-12-01

45

Effect of preparation conditions on the optical and physical properties of an epoxy-functional inorganic-organic hybrid material system  

Microsoft Academic Search

A hybrid material system consisting of (3-glycidyloxypropyl)trimethoxysilane, dimethyldimethoxysilane and zirconium(IV) n-propoxide was prepared. The influence of processing parameters including Zr content, UV irradiation and sol ageing on the\\u000a properties of the resultant thin films was discussed. Refractive index, at 633 nm, and reflectance measurements were performed\\u000a and near-field waveguide images of the samples were taken. Optical propagation loss measurements, at

Mehmet Çopuro?lu; Shane O’Brien; Gabriel M. Crean

2006-01-01

46

TOPICAL REVIEW: Hybrid inorganic organic materials: a new family in condensed matter physics  

Microsoft Academic Search

We review some recent trends in an emerging field at the interface between classical inorganic and organic materials. Hybrid inorganic-organic framework materials are crystalline systems in which both inorganic and organic structural elements co-exist within a single phase. Much of the focus in this area during the last few years has been on porous hybrid frameworks, which are of interest

C. N. R. Rao; A. K. Cheetham; A. Thirumurugan

2008-01-01

47

Hybrid inorganic–organic materials: a new family in condensed matter physics  

Microsoft Academic Search

We review some recent trends in an emerging field at the interface between classical inorganic and organic materials. Hybrid inorganic–organic framework materials are crystalline systems in which both inorganic and organic structural elements co-exist within a single phase. Much of the focus in this area during the last few years has been on porous hybrid frameworks, which are of interest

C N R Rao; A K Cheetham; A Thirumurugan

2008-01-01

48

Novel inorganic materials for polymer electrolyte and alkaline fuel cells  

NASA Astrophysics Data System (ADS)

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.

Tadanaga, Kiyoharu

2012-06-01

49

Hybrid exciton recombination dynamics in inorganic-organic materials  

NASA Astrophysics Data System (ADS)

A systematic analysis of hybrid Frenkel-Wannier-Mott excitons recombination dynamics in nanocomposite material (organic-inorganic) is performed. A theoretical model based on the rate equation is used in the calculation of the light intensity and relative quantum efficiency. Numerical results have been presented for low and high concentration of quantum dots (Qds). Our results show that the light emission and relative quantum efficiency are significantly enhanced by incorporation of Qds in polymer matrix. Moreover our calculations were found to be in good agreement with the experimental data.

Mastour, N.; Bouchriha, H.

2013-12-01

50

Phases of functionalized polymer-inorganic composites in solution studied via molecular dynamics  

NASA Astrophysics Data System (ADS)

Using self-assembling polymer systems to direct the formation of inorganic crystals, polymer-inorganic composite materials offer new opportunities in materials design. Molecular dynamics simulations allow for an exploration of the wide range of phases in these systems. Amphiphilic ABA triblocks with A hydrophilic, B hydrophobic, and functional ends with an affinity to inorganic particles are modeled to capture the minimum physics needed to describe polymer-inorganc systems currently being investigated by experiment. A number of phases are formed in solution as the attraction strength between the inorganic particles and the affinity of those particles to the functional end beads of the polymer are varied. Some of the phases found include hexagonal, square columnar, lamellar, perforated lamellar, and the gyroid. Polymer stretching plays an important role in each of the phases found, with a characteristic multi-modal behavior in the polymer end to end distance distribution. In the gyroid phase, for instance, the peaks correspond to the polymers being in two preferred conformations: v-shaped with a small end to end distance and fully extended in a line with the largest possible end to end distance. At high interaction strengths, inorganic particles are found to crystallize and form plate-like structures.

Anderson, Joshua; Sknepnek, Rastko; Travesset, Alex

2009-03-01

51

Organic/inorganic hybrid amine and sulfonic acid tethered silica materials: Synthesis, characterization and application  

NASA Astrophysics Data System (ADS)

The major goals of this thesis were to: (1) create a site-isolated aminosilica material with higher amine loadings than previously reported isolation methods, (2) use spectroscopic, reactivity, and catalytic (olefin polymerization precatalysts) probes to determine isolation of amine groups on these organic/inorganic hybrid materials, (3) synthesize an organic/inorganic hybrid material capable of activating Group 4 olefin polymerization precatalysts, and (4) synthesize a high amine loaded organic/inorganic hybrid material capable of reversibly capturing CO2 in a simulated flue gas stream. The underlying motivation of this research involved the synthesis and design of novel amine and sulfonic acid materials. Traditional routes to synthesize aminosilicas have led to the formation of a high loading of multiple types of amine sites on the silica surface. Part of this research involved the creation of a new aminosilica material via a protection/deprotection method designed to prevent multiple sites, while maintaining a relatively high loading. As a characterization technique, fluorescence spectroscopy of pyrene-based fluorophores loaded on traditional aminosilicas and site-isolated aminosilicas was used to probe the degree of site-isolation obtained with these methods. Also, this protection/deprotection method was compared to other reported isolation techniques with heterogeneous Group 4 constrained-geometry inspired catalysts (CGCs). It was determined that the degree of separation of the amine sites could be controlled with protection/deprotection methods. Furthermore, an increase in the reactivity of the amines and the catalytic activity of CGCs built off of the amines was determined for aminosilicas synthesized by a protection/deprotection method. The second part of this work involved developing organic/inorganic hybrid materials as heterogeneous Bronsted acidic cocatalysts for activation of olefin polymerization precatalysts. This was the first reported organic/inorganic hybrid sulfonic acid functionalized silica material capable of activating metallocenes for the polymerization of ethylene when small amounts of an alkylaluminum was added. Lastly, an organic/inorganic hybrid hyperbranched aminosilica material capable of capturing carbon dioxide from flue gas streams was synthesized. This material was determined to capture CO2 with capacities higher than currently reported aminosilica adsorbents.

Hicks, Jason Christopher

52

Bioinspired synthesis of multifunctional inorganic and bio-organic hybrid materials.  

PubMed

Owing to their physical and chemical properties, inorganic functional materials have tremendous impacts on key technologies such as energy generation and storage, information, medicine, and automotive engineering. Nature, on the other hand, provides evolution-optimized processes, which lead to multifunctional inorganic-bio-organic materials with complex structures. Their formation occurs under physiological conditions, and is goverened by a combination of highly regulated biological processes and intrinsic chemical properties. Nevertheless, insights into the molecular mechanisms of biomineralization open up promising perspectives for bioinspired and biomimetic design and the development of inorganic-bio-organic multifunctional hybrids. Therefore, biomimetic approaches may disclose new synthetic routes under ambient conditions by integrating the concept of gene-regulated biomineralization principles. The skeletal structures of marine sponges provide an interesting example of biosilicification via enzymatically controlled and gene-regulated silica metabolism. Spicule formation is initiated intracellularly by a fine-tuned genetic mechanism, which involves silica deposition in vesicles (silicassomes) under the control of the enzyme silicatein, which has both catalytic and templating functions. In this review, we place an emphasis on the fabrication of biologically inspired materials with silicatein as a biocatalyst. PMID:22510103

Andre, Rute; Tahir, Muhammad N; Natalio, Filipe; Tremel, Wolfgang

2012-05-01

53

High Affinity Anti-inorganic Material Antibody Generation by Integrating Graft and Evolution Technologies  

PubMed Central

Recent advances in molecular evolution technology enabled us to identify peptides and antibodies with affinity for inorganic materials. In the field of nanotechnology, the use of the functional peptides and antibodies should aid the construction of interface molecules designed to spontaneously link different nanomaterials; however, few material-binding antibodies, which have much higher affinity than short peptides, have been identified. Here, we generated high affinity antibodies from material-binding peptides by integrating peptide-grafting and phage-display techniques. A material-binding peptide sequence was first grafted into an appropriate loop of the complementarity determining region (CDR) of a camel-type single variable antibody fragment to create a low affinity material-binding antibody. Application of a combinatorial library approach to another CDR loop in the low affinity antibody then clearly and steadily promoted affinity for a specific material surface. Thermodynamic analysis demonstrated that the enthalpy synergistic effect from grafted and selected CDR loops drastically increased the affinity for material surface, indicating the potential of antibody scaffold for creating high affinity small interface units. We show the availability of the construction of antibodies by integrating graft and evolution technology for various inorganic materials and the potential of high affinity material-binding antibodies in biointerface applications. PMID:20044483

Hattori, Takamitsu; Umetsu, Mitsuo; Nakanishi, Takeshi; Togashi, Takanari; Yokoo, Nozomi; Abe, Hiroya; Ohara, Satoshi; Adschiri, Tadafumi; Kumagai, Izumi

2010-01-01

54

Dense organic-inorganic framework materials containing transition metal ions  

NASA Astrophysics Data System (ADS)

Hybrid inorganic-organic framework materials built upon metal cations and polyfunctional anionic ligands have arrived at the forefront of chemical research, boasting unique properties that derive from their diverse structures. The majority of these compounds are prepared through mild hydrothermal or solvothermal synthesis, at temperatures below 225°C. There has been a great deal of emphasis on porous coordination polymers, or "metal-organic frameworks" (MOFs), which exhibit a wide range of useful sorption and catalytic properties, but there is growing interest in a second class of hybrid frameworks which are denser and often have extended inorganic connectivity, which may be thought of as hybrid metal oxides. These denser compounds provide access to more oxide-like properties such as magnetism, along with improved thermal stability. The flourishing diversity of structures and dimensionalities seen in these materials has led to their growth into a major field of research. Here, the hydrothermal syntheses and crystal structures of fourteen new hybrid framework materials are reported, and additional properties are measured for several of them. The terminology used to describe this class of materials is laid out, and a classification scheme is introduced based on the dimensionalities of their structures. While a combinatorial approach for new compound discovery is often used, strategies for rational synthesis are also discussed. A family of isostructural 3,4,5-trihydroxybenzoate (gallate) hybrid frameworks of the first-row transition metals is produced, with chiral structures imparted by helical packing arrangements. Complex magnetic behavior is characterized in a pillared layered cobalt ethanedisulfonate, the structure of which features intricate metal-oxygen-metal connectivity. Frameworks of new, sometimes unreported, ligand molecules are created through the reactivities of aspartic acid and 5-hydroxyisophthalic acid under hydrothermal conditions. A family of two-ligand frameworks are created using 5-hydroxyisophthalic acid and 4,4'-bipyridyl, which form very different structures when reacted with Mn, Ni, Cu and Zn. Finally, reactions of Cu and Zn together with these two ligands lead to a family of four- and five-component hybrid frameworks showing even greater degrees of structural complexity.

Feller, Russell Kenneth

55

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

E-print Network

ReViews Inorganic Materials as Catalysts for Photochemical Splitting of Water Frank E. Osterloh and O2 using solar energy is a process of great economic and environmental interest. Since the discovery materials have been discovered as catalysts for this reaction. This review discusses the known inorganic

Osterloh, Frank

56

Sugar-derived organogels as templates for structured, photoluminescent conjugated polymer-inorganic hybrid materials.  

PubMed

Co-assembly of an inorganic-organic hybrid material through the combination of supramolecular organogel self-assembly, phase partitioning of a conjugated polymer (CP) and transcription of an inorganic oxide leads to a hybrid material with structured domains of organogel, CP and silica within tube and rod microstructures. PMID:23727663

Marr, Patricia C; McBride, Katherine; Evans, Rachel C

2013-07-14

57

Design and synthesis of inorganic/organic hybrid electrochemical materials  

NASA Astrophysics Data System (ADS)

An ambient pressure method for drying sol-gel materials is developed to synthesize high porosity (80--90%), high surface area vanadium oxide and silica aerogel materials (150--300 and 1000 m2/g for vanadium pentoxide and silica, respectively). The synthesis approach uses liquid exchange to replace the pore fluid with a low surface tension, nonpolar solvent which reduces the capillary pressures developed during drying. The Good-Girifalco interaction parameter is used to calculate pore stresses resulting from drying silica gels from various liquids. Vanadium oxide/polypyrrole hybrid aerogels are prepared using three strategies. These approaches focus on either sequential or consecutive polymerization of the inorganic and organic networks. Microcomposite aerogels are synthesized by encapsulating a dispersion of preformed polypyrrole in a vanadium pentoxide gel. In the second approach, pyrrole is polymerized and doped within the pore volume of preformed vanadium pentoxide gel. When the inorganic and organic precursors are polymerized simultaneously, the resulting gels exhibited a nanometer scaled microstructure with homogeneous distributions of either phases. Through this route, a suitable microstructure and composition for a lithium secondary battery cathode is obtained. Lithiated aerogels of hydrated nickel, cobalt, and mixed nickel-cobalt oxides are synthesized from lithium hydroxide and transition metal acetate precursors. The XRD analyses indicate that the nickel containing gels exhibit a lithium deficiency (less than 1 Li/transition metal. By increasing the concentration of the lithium precursor the lithium content in nickel oxides is increased, and additional base solution is no longer required to catalyze gelation. A non-hydrolytic sol-gel approach is utilized to create tin oxide and tin-aluminum binary oxide aerogels with high porosity (90%) and high surface area (300 m2/g). XRD data from single phase tin oxide aerogel indicates the growth of SnO2 crystallites between 150--400°C in air, accompanied by a reduction in surface area (30 m2/g). Heated tin oxide aerogel exhibits comparable reversible specific capacity (390 mAh/g) as that of commercial SnO2 (420 mAh/g). Amorphous tin oxide aerogel is stabilized to higher temperatures when aluminum oxide is incorporated into the structure. The tin oxide phase remains electrochemically active towards lithium insertion and exhibits excellent reversibility during cycling.

Harreld, John H.

58

Inorganic-organic electrolyte materials for energy applications  

NASA Astrophysics Data System (ADS)

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

Fei, Shih-To

59

Inorganic arsenic impairs differentiation and functions of human dendritic cells  

SciTech Connect

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.

Macoch, Mélinda; Morzadec, Claudie [UMR INSERM U1085, Institut de Recherche sur la Santé, l'Environnement et le Travail (IRSET), Université de Rennes 1, 2 avenue du Professeur Léon Bernard, 35043 Rennes (France)] [UMR INSERM U1085, Institut de Recherche sur la Santé, l'Environnement et le Travail (IRSET), Université de Rennes 1, 2 avenue du Professeur Léon Bernard, 35043 Rennes (France); Fardel, Olivier [UMR INSERM U1085, Institut de Recherche sur la Santé, l'Environnement et le Travail (IRSET), Université de Rennes 1, 2 avenue du Professeur Léon Bernard, 35043 Rennes (France) [UMR INSERM U1085, Institut de Recherche sur la Santé, l'Environnement et le Travail (IRSET), Université de Rennes 1, 2 avenue du Professeur Léon Bernard, 35043 Rennes (France); Pôle Biologie, Centre Hospitalier Universitaire (CHU) Rennes, 2 rue Henri Le Guilloux, 35033 Rennes (France); Vernhet, Laurent, E-mail: laurent.vernhet@univ-rennes1.fr [UMR INSERM U1085, Institut de Recherche sur la Santé, l'Environnement et le Travail (IRSET), Université de Rennes 1, 2 avenue du Professeur Léon Bernard, 35043 Rennes (France)] [UMR INSERM U1085, Institut de Recherche sur la Santé, l'Environnement et le Travail (IRSET), Université de Rennes 1, 2 avenue du Professeur Léon Bernard, 35043 Rennes (France)

2013-01-15

60

Synthesis, characterization, and film fabrication of inorganic and hybrid semiconductor materials for optoelectronic applications  

NASA Astrophysics Data System (ADS)

We have developed and studied selected properties of a novel type of inorganicorganic hybrid semiconductor materials in order to enhance the functionality over their parent structures. Since these hybrid semiconductor materials are composed of both inorganic and organic segments, one may expect them to have the advantage of combining the excellent electrical, optical, thermal and transport properties from the inorganic component with the flexibility, processability and structural diversity from the organic component. As a continuing effort, we have synthesized, modified, and characterized a number of selected structures with potential for solid state lighting applications. For example, we have developed the first inorganic-organic semiconductor bulk material, double-layered 2D-Cd2Q2(ba) (Q = S, Se), capable of producing direct white light. This type of materials could be promising for use as a single-material white-light-emitting source in white LEDs. Luminescence properties of these hybrid semiconductors can be tuned systematically by changing their composition and doping level. In addition, a thin pellet of one of our hybrid semiconductor materials without any modifications showed low electrical conductivity. Significant improvement may be anticipated with compositional and structural modifications on this system. Solution processed deposition techniques provide great opportunities for optical and optoelectronic devices, such as displays, solid state lighting, and solar cells, because it enables to fabricate flexible devices with low-cost and large area fabrications. Most semiconductors show very low solubility in organic solvents, thus limiting the opportunities to prepare thin films using soluble precursors. In this study, we have developed a simple, efficient, and low-cost solution-processed deposition route to fabricate metal chalcogenide semiconductor thin films by using soluble precursors via spin-coating techniques. Surface morphology was directly influenced by the choice of organic solvents as well as the spin-coating sequences, thus affecting the electrical transport of the films. In the case of hybrid semiconductors, a conducting polymer was employed to help forming more uniform composite films.

Ki, Wooseok

61

Stability and transport of inorganic colloids through contaminated aquifer material  

SciTech Connect

Laboratory columns using contaminated natural aquifer material from Globe, Arizona, were used to investigate the transport of inorganic colloids under saturated flow conditions. Fe2O3 radio-labeled spherical colloids of various diameters were synthesized and introduced into the columns under varying conditions of pH, ionic strength, electrolyte composition, and colloid concentration. Column influent and effluent were evaluated by photon correlation spectroscopy and scintillation-counting techniques. Effluent breakthrough concentrations of the colloid were as high as 57 percent of the influent concentration under conditions. In all cases where significant transport occurred, the colloids arrived at approximately the same time as a conservative tracer, tritium. Conditions favoring colloidal transport in the system were low ionic strength and a pH in the range where the colloids are stable. Arsenate was used as a model reactive contaminant to evaluate its facilitated transport on the Fe2O3 colloids. The calculated sorption capacity of the colloids from batch tests was 1 percent by weight for arsenate. Compared to dissolved arsenate transport in the same columns, the colloids were transported more than 21 times faster.

Puls, R.W.; Powell, R.M.; Rees, T.F.

1991-01-01

62

3D Isostructurality of Inorganic-Organic Hybrid Materials  

NASA Astrophysics Data System (ADS)

The crystal structure of bis (2-methyl-4-nitroanilium) tetrachloromercurate, (I), self-assembles into organic bilayers, sandwiched between inorganic layers. In the bilayer the organic sheets are interlinked through weak C—H⋯O hydrogen bonds, while the organic and inorganic layers interact via strong, charge assisted N+—H⋯Cl- hydrogen bonds. Both the organic and inorganic sheets show antiparallel packing arrangements. Three-dimenional isostruturality is observed between (I), and the previously reported structure of bis(2-methyl-4-nitroanilium) tetrachlorocadmate, (II).

Dinesh, Dinesh; Redemeyer, M.; Kumar, Mukesh; Dalela, S.

2011-12-01

63

Interfacial and transport properties of nanoconstrained inorganic and organic materials  

NASA Astrophysics Data System (ADS)

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.

Kocherlakota, Lakshmi Suhasini

64

Modification of Thermo-Optic Characteristics of Sol-Gel Inorganic-Organic Hybrid Materials  

Microsoft Academic Search

The effect of the inorganic oxide network on the variation of thermo-optic characteristics (dn\\/dT) in inorganic-organic hybrid material prepared through the sol-gel process was investigated. The dn\\/dT values were negative for all samples, and decreased in magnitude with the increasing concentration of the inorganic oxide or heterometallic oxide network. The dn\\/dT also became less negative with the increase in the

Eun-Seok Kang; Woo-Soo Kim; Kwang-Soo Kim; Byeong-Soo Bae

2004-01-01

65

Various methods for the synthesis of inorganic-organic hybrid materials  

Microsoft Academic Search

Summaries  New technologies and the necessity to supply suitable materials for these technologies have inspired a growing interest in\\u000a novel inorganic-organic hybrid materials with the aim of combining the inherent properties of inorganic materials with those\\u000a of organic polymers. In this paper, three different ways of synthesing hybrid materials by the sol-gel route are described.\\u000a \\u000a The classical approach comprises the formation

K Rose

2003-01-01

66

Mn-Substituted Inorganic-Organic Hybrid Materials Based on ZnSe  

E-print Network

Mn-Substituted Inorganic-Organic Hybrid Materials Based on ZnSe: Nanostructures That May Lead developed a synthetic strategy in assembling a unique class of inorganic-organic hybrid nanostructures MQ for optoelectronics and information storage technology. In this study, we demonstrate that the hybrid nanostructures

Li, Jing

67

Thermal/chemical degradation of inorganic membrane materials  

SciTech Connect

The overall objective of this program is to evaluate the long-term thermal and chemical degradation of inorganic membranes that are being developed to separate gaseous products produced by the gasification or combustion of coal in fixed-, fluidized-, and entrained-bed gasifiers, direct coal-fired turbines, and pressurized-fluidized-bed combustors. Specific objectives of this program are to (1) quantify the extent of the degradation process for the three most detrimental mechanisms by performing laboratory-scale experiments, and (2) develop a predictive model for membrane degradation under operating conditions. At present, no inorganic membranes are commercially available for application in the high-temperature, high-pressure (HTHP) gas environments encountered in integrated gasification combined cycle (IGCC), pressurized fluidized bed combustion (PFBC), and direct coal fired turbine (DCFT) applications. Most of the inorganic membrane development efforts have focused on hydrogen separation membranes which may be used in an IGCC system for maximizing hydrogen production from coal gas or to remove H{sub 2}S and NH{sub 3} contaminants via thermal or catalytic decomposition of these contaminants. The candidate inorganic membranes may be grouped as follows: dense metallic membranes; silica based membranes; alumina based membranes; and carbon based membranes. Results are reported for membrane characterization done so far.

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

1994-10-01

68

Ageing Effect on the SiO2-based Inorganic-Organic Hybrid Materials  

Microsoft Academic Search

It is well known that SiO2 -based inorganic-organic hybrid materials present significant differences due to the organic moieties bound to the inorganic\\u000a network and to the preparation conditions.\\u000a \\u000a In the present work the ageing effect on the thermal stability of the SiO2 -based inorganic-organic hybrid materials prepared using tetraethoxysilan (TEOS), triethoxymethylsilan (MTEOS), triethoxyvinylsilan\\u000a (VTEOS), tetramethoxysilan (TMOS), trimethoxymethylsilan (MTMOS) and trimethoxyvinylsilan

M. Zaharescu; A. Jitianu; A. Braileanu; J. Madarász; G. Pokol

2001-01-01

69

Inorganic–organic hybrid materials with zirconium oxoclusters as protective coatings on aluminium alloys  

Microsoft Academic Search

Inorganic–organic hybrid materials are attracting a strong scientific interest mainly for their outstanding inherent mechanical and thermal properties, which can be traced back to the intimate coupling of both inorganic and organic components. By carefully choosing the experimental parameters used for their synthesis, chemically and thermally stable acrylate-based hybrid material embedding the zirconium oxocluster Zr4O4(OMc)12, where OMcCH2C(CH3)C(O)O, can be deposited

Fabrizio Girardi; Francesco Graziola; Paolo Aldighieri; Lorenzo Fedrizzi; Silvia Gross; Rosa Di Maggio

2008-01-01

70

Thermal Stability of SiO2Based Inorganic-Organic Hybrid Materials  

Microsoft Academic Search

The hydrolysis-polycondensation of organically modified Si-alkoxides leads to the obtaining of inorganic-organic hybrid materials\\u000a in which the organic moieties remain as permanent groups bonded to the inorganic network.\\u000a \\u000a The molecular species previously determinated by GC-MS during the gelation process have been significantly different according\\u000a to the type of the alkoxide used.\\u000a \\u000a \\u000a \\u000a In the present work, thermal stability of SiO2-based inorganic-organic

M. Zaharescu; A. Jitianu; A. Brãileanu; V. Bãdescu; G. Pokol; J. Madarász; Cs. Novák

1999-01-01

71

Tetraalkylphosphonium polyoxometalate ionic liquids : novel, organic-inorganic hybrid materials.  

SciTech Connect

Pairing of a Keggin or Lindqvist polyoxometalate (POM) anion with an appropriate tetraalkylphosphonium cation is shown to yield the first members of a new family of ionic liquids (ILs). Detailed characterization of one of them, an ambient-temperature 'liquid POM' comprising the Lindqvist salt of the trihexyl(tetradecyl) phosphonium cation, by voltammetry, viscometry, conductimetry, and thermal analysis indicates that it exhibits conductivity and viscosity comparable to those of the one previously described inorganic-organic POM-IL hybrid but with substantially improved thermal stability.

Rickert, P. G.; Antonio, M. P.; Firestone, M. A.; Kubatko, K.-A.; Szreder, T.; Wishart, J. F.; Dietz, M. L.; Chemistry; Univ. of Notre Dame; BNL

2007-01-01

72

Utilization and Modification of Perovskite-Type Layered Structures as Inorganic-Organic Hybrid Materials  

Microsoft Academic Search

The aromatic ammonium-based layered halide compounds were obtained of bis(4-nitroanilinium)tetrachlorocadmate and bis(2-methyl-4-nitroanilinium) tetrachlorocadmate, aiming at a new type of inorganic-organic hybrid layered material. X-ray diffraction analyses of the single crystals revealed that both of the crystals take an alternate layered structure of the organic bilayer and the inorganic sheet. Cadmium ion and chloride anions form six-coordinated octahedra whose corner anions

Reiko Azumi; Kazumasa Honda; Midori Goto; Junji Akimoto; Yoshinao Oosawa; Hiroaki Tachibana; Motoo Tanaka; Mutsuyoshi Matsumoto

1996-01-01

73

Fabrication of Thermally Durable Sub-wavelength Periodic Structures upon Inorganic-Organic Hybrid Materials by Nano-imprinting  

Microsoft Academic Search

We fabricated sub-wavelength periodic structures by thermal nano-imprinting using our original functionally modified inorganic-organic hybrid materials. The fabricated structures exhibited excellent uniformity and surface smoothness over a large imprinted area. In addition, optical transmittance is more than 90% within visible wavelength regions after heat treatment for 2 h at 300 °C. These nano-imprinted periodic structures showed high thermal durability without

Dong Jun Kang; Byeong-Soo Bae; Junji Nishii

2007-01-01

74

Fabrication and characterization of photocurable inorganic–organic hybrid materials using organically modified colloidal-silica nanoparticles and acryl resin  

Microsoft Academic Search

Photocurable inorganic–organic hybrid materials were prepared from colloidal-silica nanoparticles synthesized through the sol–gel process and using acryl resin. The synthesized colloidal-silica nanoparticles had uniform diameters of around 20nm and were organically modified, using methyl and methacryl functional silanes, for efficient hybridization with acryl resin. The organically modified and stabilized colloidal-silica nanoparticles could be homogeneously hybridized with acryl resin without phase

Dong Jun Kang; Dong Hee Han; Dong Pil Kang

2009-01-01

75

Medical applications of organic-inorganic hybrid materials within the field of silica-based bioceramics.  

PubMed

Research on bioceramics has evolved from the use of inert materials for mere substitution of living tissues towards the development of third-generation bioceramics aimed at inducing bone tissue regeneration. Within this context hybrid bioceramics have remarkable features resulting from the synergistic combination of both inorganic and organic components that make them suitable for a wide range of medical applications. Certain bioceramics, such as ordered mesoporous silicas, can exhibit different kind of interaction with organic molecules to develop different functions. The weak interaction of these host matrixes with drug molecules confined in the mesoporous channels allows these hybrid systems to be used as controlled delivery devices. Moreover, mesoporous silicas can be used to fabricate three (3D)-dimensional scaffolds for bone tissue engineering. In this last case, different osteoinductive agents (peptides, hormones and growth factors) can be strongly grafted to the bioceramic matrix to act as attracting signals for bone cells to promote bone regeneration process. Finally, recent research examples of organic-inorganic hybrid bioceramics, such as stimuli-responsive drug delivery systems and nanosystems for targeting of cancer cells and gene transfection, are also tackled in this tutorial review (64 references). PMID:21049136

Vallet-Regí, María; Colilla, Montserrat; González, Blanca

2011-02-01

76

Strategies for the synthesis of thermoplastic polymer nanocomposite materials with high inorganic filling fraction.  

PubMed

The governing parameters controlling the miscibility of particle additives within polymeric host media are analyzed for the particular case of silica particle fillers embedded within a poly(methyl methacrylate) (PMMA) matrix. For athermal polymer-graft modification of particles (corresponding to equal chemical composition of graft and matrix polymer), compatibility is found to be a sensitive function of the degree of polymerization of graft and host polymer chains as well as the particle radius. In agreement with theoretical predictions, uniform particle dispersion is observed if the degree of polymerization of grafted chains is comparable to (or exceeds) the corresponding value of the polymer matrix. The resulting restriction to high degree of polymerization limits the accessible inorganic fraction that is attainable in athermal particle/polymer blends. In contrast, favorable interaction between grafted polymer chains and the polymeric host (as realized in the case of poly(styrene-r-acrylonitrile)-grafted particles embedded within PMMA matrix) is shown to facilitate thermodynamically stable and uniform particle dispersion across the entire compositional range even in the limit of large particle size, short grafted chains, and high molecular matrix chains. The synthesis of thermoplastic composite materials with inorganic fraction exceeding 50 vol % combining quantitative optical limiting within the UV frequency range and polymer-like mechanical properties is demonstrated. PMID:23786358

Ojha, Satyajeet; Dang, Alei; Hui, Chin Ming; Mahoney, Clare; Matyjaszewski, Krzysztof; Bockstaller, Michael R

2013-07-16

77

TOPICAL REVIEW: Hybrid inorganic organic materials: a new family in condensed matter physics  

NASA Astrophysics Data System (ADS)

We review some recent trends in an emerging field at the interface between classical inorganic and organic materials. Hybrid inorganic-organic framework materials are crystalline systems in which both inorganic and organic structural elements co-exist within a single phase. Much of the focus in this area during the last few years has been on porous hybrid frameworks, which are of interest for potential applications in catalysis, separations and sensors. The primary focus of our overview is on properties that traditionally lie in the domain of condensed matter physics: magnetism, optical, electronic and dielectric properties. We show that these materials exhibit a rich diversity of behavior in these areas and present some exciting opportunities for the physics community. We also present a short summary of some of the properties found in porous materials.

Rao, C. N. R.; Cheetham, A. K.; Thirumurugan, A.

2008-02-01

78

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

NASA Technical Reports Server (NTRS)

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.

Lee, S. M.

1979-01-01

79

Inorganic Compounds for Passive Solar Energy Storage - Solid-State Dehydration Materials and High Specific Heat Materials.  

National Technical Information Service (NTIS)

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-A12O3-SO3-h2O and related chemical systems, and the two classes are typi...

L. Struble, P. Brown

1986-01-01

80

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

E-print Network

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 ...

Peelle, Beau R

2005-01-01

81

Integrative self-assembly of functional hybrid nanoconstructs by inorganic wrapping of single biomolecules, biomolecule arrays and organic supramolecular assemblies  

NASA Astrophysics Data System (ADS)

Synthesis of functional hybrid nanoscale objects has been a core focus of the rapidly progressing field of nanomaterials science. In particular, there has been significant interest in the integration of evolutionally optimized biological systems such as proteins, DNA, virus particles and cells with functional inorganic building blocks to construct mesoscopic architectures and nanostructured materials. However, in many cases the fragile nature of the biomolecules seriously constrains their potential applications. As a consequence, there is an on-going quest for the development of novel strategies to modulate the thermal and chemical stabilities, and performance of biomolecules under adverse conditions. This feature article highlights new methods of ``inorganic molecular wrapping'' of single or multiple protein molecules, individual double-stranded DNA helices, lipid bilayer vesicles and self-assembled organic dye superstructures using inorganic building blocks to produce bio-inorganic nanoconstructs with core-shell type structures. We show that spatial isolation of the functional biological nanostructures as ``armour-plated'' enzyme molecules or polynucleotide strands not only maintains their intact structure and biochemical properties, but also enables the fabrication of novel hybrid nanomaterials for potential applications in diverse areas of bionanotechnology.

Patil, Avinash J.; Li, Mei; Mann, Stephen

2013-07-01

82

Fifteen years of operation with inorganic highly selective ion exchange materials  

Microsoft Academic Search

During latest fifteen years three highly selective inorganic ion exchange materials, CsTreat{sup R}, SrTreat{sup R}, and CoTreat, have been in full scale commercial use. All these materials have high capacity, and they give high decontamination factor (DF) and remarkably good volume reduction factor for storage and final disposal. A new material for antimony removal is currently coming for demonstration phase.

E. Tusa; R. Harjula; P. Yarnell

2007-01-01

83

Photoreduction of Europium (III) in Sol-Gel Derived Inorganic-Organic Hybrid Materials  

Microsoft Academic Search

Eu2+-doped inorganic-organic hybrid materials, which are potentially suitable for a tunable laser in the near ultra violet and blue region, were prepared through the photoreduction of Eu3+ ions in the materials under the irradiation of the fourth harmonic wave light (266 nm) of the Nd:YAG laser. The hybrid materials doped with Eu3+ ions were prepared from Si(OCH3)4, CH3Si(OCH3)3, EuCl3 and

M. Iwasaki; N. Sato; J. Kuraki; S. Ito

2000-01-01

84

Thermal and chemical degradation of inorganic membrane materials. Final report, August 1992--May 1995  

SciTech Connect

SRI International conducted a theoretical and experimental program to evaluate the long-term thermal and chemical degradation of inorganic membranes that are being developed to separate the gaseous products of coal gasification. A variety of developmental efforts are underway, including a number of projects sponsored by the US Department of Energy (DOE), to improve the selectivity and permeability of porous inorganic membranes. DOE is also sponsoring efforts to extend the use of metallic membranes to new applications. Most developmental efforts have focused on hydrogen separation by inorganic membranes, which may be used to maximize hydrogen production from coal gas or to remove H{sub 2}S and NH{sub 3} contaminants via thermal or catalytic decomposition in integrated-gasification combined-cycle (IGCC) systems. Inorganic membranes that have a high separation efficiency and exhibit both thermal and chemical stability would improve the economics of power generation from coal. Membrane materials that have been investigated include glass (silica), alumina, carbon, and metals (Pd and Pt). This report describes inorganic membrane materials, long term membrane exposure tests, membrane permeation tests, coal gasifier exposure tests, conclusions, and recommendations.

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

1995-05-01

85

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

NASA Technical Reports Server (NTRS)

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.

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

1976-01-01

86

Microstructural fabrication and design of sunlight guide panels of inorganic–organic hybrid material  

Microsoft Academic Search

This study demonstrates a sunlight guide panel with a UV-imprinted microstructure that improves sunlight utilization in buildings. The panel that was assembled to the transoms of a building guides sunlight from outdoors to enhance indoor lighting. To match the requirements of outdoor applications, an inorganic–organic hybrid material was adopted for high weather resistance and transparency. An optical analysis was conducted

Hong Hocheng; Tzu-Yu Huang; Ta-Hsin Chou; Wen-Hsien Yang

2011-01-01

87

Pore formation in inorganic-organic hybrid material by oxygen plasma treatment  

Microsoft Academic Search

In this work, the use of inorganic-organic hybrid material, ORMOCER (registered trademark of Microresist Technology), is studied. Pores are formed by oxygen plasma which makes the pore formation on pre-patterned surfaces possible. Patterning of porous and non-porous areas on a same substrate can be done by using shadow mask or a deposited thin film as a mask.

S. Aura; V. Jokinen; M. Baumann; S. Franssila

2009-01-01

88

High-loading effect of surface-modified inorganic particles in polymer materials  

Microsoft Academic Search

Recently fine-particle technology has been extending its application not only to existing multiphase metals, paint and coatings, but also to other wider industrial fields (such as polymers, ceramics, etc.). In the polymer industries, inorganic particles (mica, talc, calcium carbonate, etc.) are combined to polymer materials in order to improve the stiffness and thermal stability, but the lack of affinity at

Kazuta Mitsuishi; Tatsumi Yabuki; Soji Kodama; Hitoshi Kawasaki

1989-01-01

89

Nanocomposite Materials from Functional Polymers and Magnetic Colloids  

Microsoft Academic Search

The synthesis of polymer coated magnetic nanoparticles is reviewed. This class of organic\\/inorganic materials has gained significant attention for potential applications in biomedicine, separations, and magnetic storage. We outline the various approaches that have been investigated to encapsulate discrete magnetic colloids with functional polymer shells. An essential component of this research is the preparation of polymeric surfactants that enable synthesis,

Jeffrey Pyun

2007-01-01

90

Mechanical properties of hybrid inorganic-organic framework materials: establishing fundamental structure-property relationships.  

PubMed

The mechanical properties of hybrid framework materials, including both nanoporous metal-organic frameworks (MOFs) and dense inorganic-organic frameworks, are discussed in this critical review. Although there are relatively few studies of this kind in the literature, major recent advances in this area are beginning to shed light on the fundamental structure-mechanical property relationships. Indeed research into the mechanical behavior of this important new class of solid-state materials is central to the design and optimal performance of a multitude of technological applications envisaged. In this review, we examine the elasticity of hybrid frameworks by considering their Young's modulus, Poisson's ratio, bulk modulus and shear modulus. This is followed by discussions of their hardness, plasticity, yield strength and fracture behavior. Our focus is on both experimental and computational approaches. Experimental work on single crystals and amorphized monoliths involved primarily the application of nanoindentation and atomic force microscopy to determine the elastic moduli and hardness properties. The compressibility and bulk moduli of single crystals and polycrystalline powders were studied by high-pressure X-ray crystallography in the diamond anvil cell, while in one instance spectroscopic ellipsometry has also been used to estimate the elastic moduli of MOF nanoparticles and deposited films. Theoretical studies, on the other hand, encompassed the application of first principles density-functional calculations and finite-temperature molecular dynamics simulations. Finally, by virtue of the diverse mechanical properties achievable in hybrid framework materials, we propose that a new domain be established in the materials selection map to define this emerging class of materials (137 references). PMID:21221446

Tan, Jin Chong; Cheetham, Anthony K

2011-02-01

91

Pattern Replication in Organic-Inorganic Hybrid Materials  

E-print Network

which means many and meros which means parts. A usual polymer is an organic compound, containing carbon atoms together with hydrogen, oxygen, nitrogen and halogens. It is com- posed of many repeat-units called monomers, which are covalently linked... -aqueous solution to obtain the mesoporous metal- oxide species. The polymer was dissolved in ethanol and the corresponding metal chloride was added to form the required precursor. After removing the polymer by calcination the mesoporous metal-oxide materials were...

Nedelcu, Mihaela

2014-05-27

92

Low consumption power variable optical attenuator with sol-gel derived organic/inorganic hybrid materials.  

PubMed

An integrated optical waveguide variable optical attenuator (VOA) made of organic/inorganic hybrid materials was fabricated. At 1550 nm, the VOA showed a very low activation power of about 13 mW, due to the large thermo-optic coefficients of the hybrid materials. The optical power attenuations achieved were more than 25 dB for both TE and TM polarization. The response time of the device was less than 4.7 ms. PMID:19516774

Li, Dongxiao; Zhang, Yanwu; Liu, Liying; Xu, Lei

2006-06-26

93

Low consumption power variable optical attenuator with sol-gel derived organic/inorganic hybrid materials  

NASA Astrophysics Data System (ADS)

An integrated optical waveguide variable optical attenuator (VOA) made of organic/inorganic hybrid materials was fabricated. At 1550 nm, the VOA showed a very low activation power of about 13 mW, due to the large thermo-optic coefficients of the hybrid materials. The optical power attenuations achieved were more than 25 dB for both TE and TM polarization. The response time of the device was less than 4.7 ms.

Li, Dongxiao; Zhang, Yanwu; Liu, Liying; Xu, Lei

2006-06-01

94

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

NASA Astrophysics Data System (ADS)

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.

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

2013-01-01

95

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

SciTech Connect

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.

Baxter, L.L. [Sandia National Labs., Livermore, CA (United States); Jenkins, B.M. [California Univ., Davis, CA (United States). Dept. of Biological and Argicultural Engineering

1995-08-01

96

Hierarchical hybrid organic-inorganic materials with tunable textural properties obtained using zeolitic-layered precursor.  

PubMed

Novel layered zeolitic organic-inorganic materials have been synthesized using a two-dimensional zeolite precursor IPC-1P prepared by a top-down approach from zeolite UTL. The formation of porous materials containing organic linkers or polyhedral oligomeric siloxane covalently bonded to zeolite layers in the interlayer space was confirmed by a variety of characterization techniques (N2/Ar sorption analysis, XRD, (29)Si and (13)C NMR, TEM). The organic-inorganic porous hybrids obtained by intercalation with silsesquioxane posessed layered morphology and contained large crystalline domains. The hybrids exhibited mesoporous or hierarchical micro-/mesoporous systems, stable up to 350 °C. Textural properties of the formed zeolitic organic-inorganic materials can be controlled by varying the linker or synthetic conditions over a broad range. Surface areas and pore volumes of synthesized hybrids significantly exceed those for parent zeolite UTL and corresponding swollen material; the amount of micropores increased with increasing rigidity and size of the organic linker in the order biphenyl > phenylene > ethanediyl. PMID:24451039

Opanasenko, Maksym; Parker, Wallace O'Neil; Shamzhy, Mariya; Montanari, Erica; Bellettato, Michela; Mazur, Michal; Millini, Roberto; ?ejka, Ji?í

2014-02-12

97

Functional flexible organic-inorganic hybrid polymer for two photon patterning of optical waveguides  

NASA Astrophysics Data System (ADS)

The lately in literature described use of two photon based photo processes for producing optical interconnections arises the need of suitable optical functional materials. The present work concerns the development, investigation and processing of a flexible siloxane based organic-inorganic hybrid (OIH) material for the fabrication of optical waveguides for data transmission on printed circuit boards (PCBs). In the developed system the waveguide core is formed by two photon induced photopolymerization (TPIP) of selected monomers, which are dissolved in a polysiloxane matrix. Through the photo induced polymerization an interpenetrating network is generated, resulting in a refractive index change between the non-illuminated waveguide cladding and the illuminated core material. Due to the optical transparency, flexibility and chemical and thermal stability, polysiloxanes were chosen as optical matrix material. Different types of methacrylates with a high refractive index were used as monomers. In order to obtain a high contrast in refractive index, the monomers were removed from non-illuminated regions in a vacuum process after laser exposure. The written optical waveguides were evidenced by phase contrast microscopy, revealing an excellent structuring behavior of the developed material. Optical techniques e.g. cut-back measurements and light extraction tests were applied to characterize the inscribed waveguide structures and to detect the resulting optical loss. Conversion rate of the monomers, which occurred through structuring, was verified by FTIR. To determine the refractive index change upon UV irradiation spectroscopic ellipsometry was applied. As a result of the polymerization, a difference of ?n = 0.02 between the non-illuminated cladding and the illuminated core material was detected. Additionally, prototypes of optical interconnects on PCBs were fabricated by inscription of a waveguide bundle between a mounted laser and photo diode, resulting in the desired increase of the transmitted photocurrent after TPA structuring. In conclusion, the obtained results demonstrate that fully flexible optical interconnects are accessible by the developed process.

Bichler, Sabine; Feldbacher, Sonja; Woods, Rachel; Satzinger, Valentin; Schmidt, Volker; Jakopic, Georg; Langer, Gregor; Kern, Wolfgang

2012-03-01

98

Stabilization of Nanoscale Quasi-Liquid Interfacial Films in Inorganic Materials: A Review and Critical Assessment  

Microsoft Academic Search

Recent observations of three classes of nanometer-thick, disordered, interfacial films in multicomponent inorganic materials are reviewed and critically assessed. The three classes of films are equilibrium-thickness intergranular films (IGFs) in ceramics, their free-surface counterparts, that is, surficial amorphous films (SAFs), and their metallic counterparts. Also briefly reviewed are several related wetting and adsorption phenomena in simpler systems, including premelting in

Jian Luo

2007-01-01

99

Applications of Solid-State NMR to the Study of Organic\\/Inorganic Multicomponent Materials  

Microsoft Academic Search

The characterization of a variety of organic\\/inorganic multicomponent materials (OIMM) through solid-state NMR (SSNMR) spectroscopy will be reviewed. Many examples of applications to OIMM will be described, based on the observation of different nuclei and the use of various SSNMR methods, such as 1D and 2D techniques, measurements on relaxation and spin diffusion processes. OIMM are a very general category

Marco Geppi; Silvia Borsacchi; Giulia Mollica; Carlo Alberto Veracini

2009-01-01

100

Polarization dependence of optical Kerr effect in metallophthalocyanine-doped inorganic–organic hybrid materials  

Microsoft Academic Search

Ultrafast optical Kerr effect of metallophthalocyanine-doped inorganic–organic materials was investigated using a femtosecond optical Kerr shutter at wavelength of 800nm. Experimental results showed that the dependence of the Kerr signals on the polarization angle between the pump beam and the probe beam could be controlled by changing the pump-probe intensity ratio. The pump-intensity dependence of the polarization characters of the

Juanjuan Yue; Lihe Yan; Jinhai Si; Feng Chen; Qing Yang; Xun Hou; Guodong Qian; Jiayu Guo

2009-01-01

101

Synthesis of inorganic-organic hybrid materials from TEOS, TBT and PDMS  

Microsoft Academic Search

Inorganic-organic hybrid materials have been synthesized by reaction of tetraethoxysilane (TEOS), titanium tetrabutoxide (TBT) and silanol-terminated polydimethylsiloxane (PDMS). The hydrolysis and polymerization reactions of TEOS and PDMS in presence of TBT have been followed by means of FT-IR spectroscopy. Hydrolysis reactions have been characterized by Si—O—C and Ti—O—C bonds and polymerization reactions by Si—O—Si, Si—O—Ti and Ti—O—Ti bonds. The instantaneous

L. Téllez; J. Rubio; F. Rubio; E. Morales; J. L. Oteo

2003-01-01

102

Femtosecond laser-induced two-photon polymerization of inorganic-organic hybrid materials for applications in photonics  

Microsoft Academic Search

Investigations of two-photon polymerization of inorganic-organic hybrid materials initiated by femtosecond Ti:sapphire laser pulses are performed. First applications of this technique for the fabrication of three-dimensional microstructures and photonic crystals in inorganic-organic hybrid polymers with a structure size down to 200 nm and a periodicity of 450 nm are discussed.

J. Serbin; A. Egbert; A. Ostendorf; B. N. Chichkov; R. Houbertz; G. Domann; J. Schulz; C. Cronauer; L. Fröhlich; M. Popall

2003-01-01

103

Al-centered functionalized inorganic-organic hybrid sorbent containing N and S donor atoms for effective removal of cadmium  

NASA Astrophysics Data System (ADS)

A new aluminium-incorporated layered inorganic-organic hybrid material (Al-GPTS-TU) has been successfully synthesized by using sol-gel based precursor under mild temperature condition and silylaing agent (GPTS-TU) derived from the reaction of 3-glycidoxypropyltrimethoxysilane (GPTS) and thiourea (TU). The hybrid material was characterized by using various instrumentation techniques and the result confirmed the attachment of organic functionality to the inorganic silicon network. The inter-lamellar distance for the hybrid material was found to be 41.33 Å. The synthesized hybrid was used for the removal of cadmium from dilute aqueous solution with variation of solution parameters. Thermodynamic parameters ? H and ? S, evaluated for the adsorption of cadmium from water solution, were found to be 73.68 kJ mol -1 and 282.9 J mol -1 K -1, respectively, indicating adsorption process to be endothermic in nature. The negative value of ? G indicated the feasibility and spontaneity of ongoing adsorption process. The hybrid material containing multiple coordination sites such as S and N in the attached organic functionality can find potential applications for the removal of various metal toxicants from water bodies to prevent the eco-system.

Dey, R. K.; Patnaik, Tanushree; Singh, V. K.; Swain, S. K.; de Melo, Maurcio Alves, Jr.; Airoldi, Claudio

2010-04-01

104

Inorganic resist materials based on zirconium phosphonate for atomic force microscope lithography  

NASA Astrophysics Data System (ADS)

New inorganic resist materials based on metal complexes were investigated for atomic force microscope (AFM) lithography. Phosphoric acids are good for self-assembly because of their strong binding energy. In this work, zirconium phosphonate system are newly synthesized for spin-coatable materials in aqueous solutions and leads to negative tone pattern for improving line edge roughness. Low electron exposure by AFM lithography could generate a pattern by electrochemical reaction and cross-linking of metal-oxo complexes. It has been reported that the minimum pattern results are affected by lithographic speed, and the applied voltage between a tip and a substrate.

Kang, Mankyu; Kim, Seonae; Jung, JinHyuck; Kim, Heebom; Shin, Inkyun; Jeon, Chanuk; Lee, Haiwon

2014-03-01

105

Anion-exchangeable inorganic-organic hybrid materials synthesized without using templates  

Microsoft Academic Search

Inorganic-organic hybrid materials have been obtained at room temperature in aqueous solution without using the templates\\u000a of surfactants. The materials are carefully characterized by anion-exchange measurement, elements analysis, X-ray diffraction,\\u000a and infrared spectroscopy. Notably, the anion-exchange capacity of the samples (3.9 mmol·g?1) is even higher than anion-exchangeable resins. Interestingly, both small and large anions could be easily exchanged into\\u000a the

Xianzhu Xu; Jiangwei Song; Defeng Li; Fengshou Xiao

2004-01-01

106

Electrochemical sensing of heavy metal ions with inorganic, organic and bio-materials.  

PubMed

As heavy metal ions severely harm human health, it is important to develop simple, sensitive and accurate methods for their detection in environment and food. Electrochemical detection featured with short analytical time, low power cost, high sensitivity and easy adaptability for in-situ measurement is one of the most developed methods. This review introduces briefly the recent achievements in electrochemical sensing of heavy metal ions with inorganic, organic and bio-materials modified electrodes. In particular, the unique properties of inorganic nanomaterials, organic small molecules or their polymers, enzymes and nucleic acids for detection of heavy metal ions are highlighted. By employing some representative examples, the design and sensing mechanisms of these electrodes are discussed. PMID:25108108

Cui, Lin; Wu, Jie; Ju, Huangxian

2015-01-15

107

Mapping Proxy Sensitivity: A New Technique for Compositional Analysis of Cultured Biominerals and Inorganically Precipitated Materials  

NASA Astrophysics Data System (ADS)

Mineral composition is controlled by a host of environmental factors during precipitation. To build accurate paleo-reconstructions we need to separate the impact of each parameter on proxy behavior and use these data to build a chemical-scale understanding of mineral growth. Biomineral culture and inorganic precipitation experiments, where growth parameters can be manipulated independently, are uniquely suited to calibrate proxies and probe mechanism. Culture and precipitation experiments often involve overgrowth of an initial material. For example, seed crystals are used to control mineralogy and avoid nucleation during inorganic precipitation, while culture experiments in marine organisms typically start with wild specimens. New growth corresponding to the experimental conditions must be resolved from the initial material. Separation is typically achieved using microanalysis, skeletal dissection, or estimates of the initial mass and composition. Each approach imposes limits on the accuracy, precision or types of materials that can be analyzed. Slow growth rates and complicated geometries can make these techniques especially challenging when applied to biominerals. We present a method of compositional analysis for use in biological culture and inorganic growth experiments that overcomes many of these challenges. This method relies on growth in a mixed element stable isotope spike, requires neither the initial mass nor the initial composition to be known, harnesses the precision and sensitivity of bulk analysis, and applies even when it is impossible to physically identify newly grown material. Error analysis suggests this method can significantly improve the precision of metal/calcium measurements in experimentally grown material compared to current methods. Furthermore, the method can isolate different events through time, separating, for example, the impact of day and night cycles on biomineral composition. We will present metal/calcium ratios measured using the new method with living planktic foraminifera that were cultured at The Wrigley Marine Science Center on Santa Catalina Island during summer 2011 and compare our approach to other micro-analytical techniques.

Gagnon, A. C.; DePaolo, D. J.; DeYoreo, J.; Spero, H. J.; Russell, A. D.

2011-12-01

108

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

E-print Network

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, ...

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

2012-01-01

109

Measurement of the thermo-optic coefficients in sol-gel derived inorganic-organic hybrid material films  

Microsoft Academic Search

Thermo-optic coefficients (dn\\/dT) of inorganic-organic hybrid material films prepared by sol-gel process of organoalkylsilanes are measured using the prism coupler equipped with autocontrolled hot stage. In order to validate the reliability of this method, dn\\/dT of polymethylmethacrylate film is measured. dn\\/dT of inorganic-organic hybrid material films are negative and as high as the order of 10-4, which are comparable to

Eun-Seok Kang; Tae-Ho Lee; Byeong-Soo Bae

2002-01-01

110

Layered zeolitic materials: an approach to designing versatile functional solids.  

PubMed

Relevant layered zeolites have been considered in this perspective article from the point of view of the synthesis methodologies, materials characterization and catalytic implications, considering the unique physico-chemical characteristics of lamellar materials. The potential of layered zeolitic precursors to generate novel lamellar accessible zeolites through swelling, intercalation, pillarization, delamination and/or exfoliation treatments is studied, showing the chemical, functional and structural versatility exhibited by layered zeolites. Recent approaches based on the assembly of zeolitic nanosheets which act as inorganic structural units through the use of dual structural directing agents, the selective modification of germanosilicates and the direct generation of lamellar hybrid organic-inorganic aluminosilicates are also considered to obtain layered solids with well-defined functionalities. The catalytic applications of the layered zeolites are also highlighted, pointing out the high accessibility and reactivity of active sites present in the lamellar framework. PMID:24457617

Díaz, Urbano; Corma, Avelino

2014-07-21

111

Unusually stable ~100-fold reversible and instantaneous swelling of inorganic layered materials  

PubMed Central

Cells can swell or shrink in certain solutions; however, no equivalent activity has been observed in inorganic materials. Although lamellar materials exhibit increased volume with increase in the lamellar period, the interlamellar expansion is usually limited to a few nanometres, with a simultaneous partial or complete exfoliation into individual atomic layers. Here we demonstrate a large monolithic crystalline swelling of layered materials. The gallery spacing can be instantly increased ~100-fold in one direction to ~90?nm, with the neighbouring layers separated primarily by H2O. The layers remain strongly held without peeling or translational shifts, maintaining a nearly perfect three-dimensional lattice structure of >3,000 layers. First-principle calculations yield a long-range directional structuring of the H2O molecules that may help to stabilize the highly swollen structure. The crystals can also instantaneously shrink back to their original sizes. These findings provide a benchmark for understanding the exfoliating layered materials. PMID:23535653

Geng, Fengxia; Ma, Renzhi; Nakamura, Akira; Akatsuka, Kosho; Ebina, Yasuo; Yamauchi, Yusuke; Miyamoto, Nobuyoshi; Tateyama, Yoshitaka; Sasaki, Takayoshi

2013-01-01

112

Nanocrystal-Based Polymer Composites as Novel Functional Materials  

Microsoft Academic Search

\\u000a This chapter provides an overall picture of nanocrystal-polymer based composites and describes the key properties of these\\u000a original functional materials, particularly suited for advanced applications in photonic, optoelectronic as well as in sensing.\\u000a Here, we aim at pointing out the relevance of the incorporation of inorganic colloidal nanocrystals with size-dependent properties\\u000a in highly processable polymers. Due to the countless different

M. Striccoli; M. L. Curri; R. Comparelli

113

U.S./Russian materials protection, control and accounting program efforts at the Institute of Inorganic Materials  

SciTech Connect

The All-Russian Scientific Research Institute of Inorganic Materials (VNIINM) performs research in nuclear power reactor fuel, spent fuel reprocessing and waste management, materials science of fissionable and reactor structural materials, metallurgy, superconducting materials, and analytical sciences. VNIINM supports the Ministry of Atomic Energy of the Russian Federation (MINATOM) in technologies for fabrication and processing of nuclear fuel. As a participant in the U.S./Russian nuclear materials protection, control and accounting (MPC&A) program, VNIINM is providing support for measurements of nuclear materials in bulk forms by developing specifications, test and evaluation, certification, and implementation of measurement methods for such materials. In 1997, VNIINM worked with Brookhaven staff in developing and documenting material control and accounting requirements for nuclear materials in bulk form, Livermore and Los Alamos staff in testing and evaluating gamma-ray spectrometry methods for bulk materials, Los Alamos staff in test and evaluation of neutron-coincidence counting techniques, Livermore and Oak Ridge staff in upgrading VNIINM'S mass-spectrometry laboratory, Pacific Northwest staff on automating VNIINM's coulometric titration system and starting a task to develop a general MC&A plan for the VNHNM site, Los Alamos staff in developing a computerized accounting system for nuclear material within VNHNM and their storage facility, and Los Alamos and Oak Ridge staff in developing a bar-code system to complement the computerized accounting system. Our paper will describe the status of this work in 1997.

Ruhter, W. D., LLNL

1997-09-01

114

Polarization dependence of optical Kerr effect in metallophthalocyanine-doped inorganic-organic hybrid materials  

NASA Astrophysics Data System (ADS)

Ultrafast optical Kerr effect of metallophthalocyanine-doped inorganic-organic materials was investigated using a femtosecond optical Kerr shutter at wavelength of 800 nm. Experimental results showed that the dependence of the Kerr signals on the polarization angle between the pump beam and the probe beam could be controlled by changing the pump-probe intensity ratio. The pump-intensity dependence of the polarization characters of the Kerr signals probably arose from the contribution of light induced transient grating (LITG) to the Kerr signals.

Yue, Juanjuan; Yan, Lihe; Si, Jinhai; Chen, Feng; Yang, Qing; Hou, Xun; Qian, Guodong; Guo, Jiayu

2009-04-01

115

Preparation and luminescence properties of inorganic–organic hybrid materials doped with lanthanide (III) complexes  

Microsoft Academic Search

Lanthanide (III) complex, [Eu(phen)2]Cl3 and [Tb(bpy)2]Cl3, were doped into the SiO2–MxOy matrices derived from tetraethyl orthosilicate (TEOS) and metal alkoxides (M(OR)n, M= Zr, Ta) by the sol–gel method. Luminescence properties of the resultant inorganic–organic hybrid materials were characterized. The emission intensity of the phosphors was dependent on the matrix composition and maximized at M:Si=1:9 in each case. The complex was

H. Li; S. Inoue; K. Machida; G. Adachi

2000-01-01

116

Assembly of bacteriophage into functional materials.  

PubMed

For the last decade, the fabrication of ordered structures of phage has been of great interest as a means of utilizing the outstanding biochemical properties of phage in developing useful materials. Combined with other organic/inorganic substances, it has been demonstrated that phage is a superior building block for fabricating various functional devices, such as the electrode in lithium-ion batteries, photovoltaic cells, sensors, and cell-culture supports. Although previous research has expanded the utility of phage when combined with genetic engineering, most improvements in device functionality have relied upon increases in efficiency owing to the compact, more densely packable unit size of phage rather than on the unique properties of the ordered nanostructures themselves. Recently, self-templating methods, which control both thermodynamic and kinetic factors during the deposition process, have opened up new routes to exploiting the ordered structural properties of hierarchically organized phage architectures. In addition, ordered phage films have exhibited unexpected functional properties, such as structural color and optical filtering. Structural colors or optical filtering from phage films can be used for optical phage-based sensors, which combine the structural properties of phage with target-specific binding motifs on the phage-coat proteins. This self-templating method may contribute not only to practical applications, but also provide insight into the fundamental study of biomacromolecule assembly in in vivo systems under complicated and dynamic conditions. PMID:23280916

Yang, Sung Ho; Chung, Woo-Jae; McFarland, Sean; Lee, Seung-Wuk

2013-02-01

117

Amperometric glucose biosensor based on sol-gel organic-inorganic hybrid material.  

PubMed

A new type of sol-gel organic-inorganic hybrid material was developed and used for the production of biosensors. This material is composed of silica sol and a grafting copolymer of poly(vinyl alcohol) with 4-vinylpyridine. It prevents the cracking of conventional sol-gel-derived glasses and eliminates the swelling of the hydrogel. The optimum composition of the hybrid material was first examined, and then glucose oxidase was immobilized in this matrix to demonstrate its application. The characteristics of the biosensor were studied by cyclic voltammetry and chronoamperometry. The biosensor exhibited a series of good properties: high sensitivity (600 nA mmol-1 L-1), short response time (11 s) and remarkable long-term stability in storage (at least 5 months). In addition, the characteristics of the second-generation biosensor with the use of tetrathiafulvalene as a mediator were discussed. PMID:11013720

Wang, B; Li, B; Deng, Q; Dong, S

1998-08-01

118

Properties of liquid inorganic-organic hybrid polymer optical waveguide materials  

NASA Astrophysics Data System (ADS)

Two kinds of liquid photopatternable inorganic-organic hybrid polymer materials polysiloxanes, named as PSQ-LL and PSQ-LH, are prepared by a sol-gel process at room temperature. The refractive indexes of waveguide materials can be tuned linearly from 1.4482 to 1.5212 at 1310nm and from 1.4478 to 1.5198 at 1550nm by blending PSQ-LL and PSQ-LH. These materials have low optical losses of 0.31dB/cm at 1310nm and 0.80dB/cm at 1550nm, and high thermal stability with 1% decomposition temperatures of 297°C (in air) and 340°C (in N2) for PSQ-LH and 313°C (in air) and 370°C (in N2) for PSQ-LL. Typical waveguide structures based on PSQ-Ls are fabricated by UV imprint technology.

Han, Xiuyou; Wang, Linghua; Liu, Yuhui; Zhang, Hongbo; Wang, Jinyan; Jian, Xigao; Zhao, Mingshan

2008-11-01

119

Synthesis of an Inorganic–Organic Hybrid Material Based on Polyhedral Oligomeric Silsesquioxane and Polystyrene via Nitroxide-Mediated Polymerization and Click Reactions  

Microsoft Academic Search

Synthesis of an inorganic–organic hybrid polymeric material composed of polystyrene and polyhedral oligomeric silsesquioxane (POSS) was carried out via nitroxide-mediated polymerization (NMP) and Click reaction. First, 4-chloromethyl styrene was polymerized in bulk at 125°C using AIBN and 4hydroxy-TEMPO as the initiator and stable free radical, respectively. Reaction of poly(4-chloromethyl styrene) (PCMS) with NaN3 in DMF yielded azide side-functional polystyrene. In

Deniz Sinirlioglu; Ali Ekrem Muftuoglu

2011-01-01

120

Selective oxidation of anthracene using inorganic–organic hybrid materials based on molybdovanadophosphoric acids  

Microsoft Academic Search

Inorganic–organic hybrid materials were synthesized by immobilization of molybdovanadophosphoric acids onto mesoporous silicas, such as MCM-41, MCM-48, and SBA-15, through an organic linker. 12-Molybdovanadophosphoric acids of the general formula H3+xPMo12?xVxO40 (x=0–3)?nH2O, such as H4[PMo11VO40]?32.5H2O, H5[PMo10V2O40]?32.5H2O, and H6[PMo9V3O40]?34H2O (represented as V1PA, V2PA, and V3PA, respectively) were prepared and immobilized onto mesoporous silica. All the catalyst materials were characterized by elemental analysis,

Ankur Bordoloi; F. Lefebvre; S. B. Halligudi

2007-01-01

121

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

PubMed

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

Liu, Fei; Song, Shuyan; Xue, Dongfeng; Zhang, Hongjie

2012-01-01

122

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

PubMed Central

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

2012-01-01

123

Inorganic Materials Division annual report, 1975. [Abstracts of papers, interval reports, and talks at Lawrence Livermore Laboratory  

Microsoft Academic Search

This compilation lists abstracts of papers, internal reports, and talks presented during 1975 at national and international meetings by members of the Geoscience and Engineering Section, Inorganic Materials Division, Chemistry and Materials Science Department, Lawrence Livermore Laboratory. Titles of talks at university and local meetings are also listed when available. The subjects range from the in situ retorting of coal

A. Duba; B. Hornady

1976-01-01

124

SNL-1, a highly selective inorganic crystalline ion exchange material for Sr{sup 2+} in acidic solutions  

Microsoft Academic Search

A new inorganic ion exchange material, called SNL-1, has been prepared at Sandia National Laboratories. Developmental samples of SNL-1 have been determined to have high selectivity for the adsorption of Strontium from highly acidic solutions (1 M HNOâ). This paper presents results obtained for the material in batch ion exchange tests conducted at various solution pH values and in the

T. M. Nenoff; S. G. Thoma; J. E. Miller; D. E. Trudell

1995-01-01

125

Amphiphilic properties of dumbbell-shaped inorganic-organic-inorganic molecular hybrid materials in solution and at an interface.  

PubMed

Five novel dumbbell-shaped polyoxometalate (POM)-based inorganic-organic-inorganic molecular hybrids are investigated both in polar solvents and at interfaces for potential amphiphilic properties, which are compared with those of conventional surfactants. These hybrids with the general formula {P(2)V(3)W(15)}(2)-bis(TRIS)-linker are formed by linking two Wells-Dawson-type clusters, [P(2)V(3)W(15)O(62)](9-), with different linear bis(TRIS) linker ligands between the two TRIS moieties. Laser light scattering (LLS) studies reveal the presence of self-assembled vesicular structures in water/acetone mixed solvents, and the vesicle size increases with increasing acetone content, suggesting a charge-regulated process. The elastic constants, which are used to calculate the bending energy during vesicle formation, reveal that the organic ligands play an important role in determining the self-assembly process and that the hybrids do demonstrate amphiphilic behavior at the water/air interface. Furthermore, it is shown that some of the hybrids form monolayers at the interface, with an average molecular area that can be correlated with their organic linkers, as determined from their ?-A isotherms. Finally, the hybrids not only display amphiphilic behavior akin to that of a surfactant but also exhibit an unusually high entropy contribution to vesicle formation as a result of their unique large, polar head groups, complex organic linkers, and their special molecular architectures as well as because of the involvement of the amphiphilic tetrabutylammonium (TBA) counterions. PMID:21661766

Misdrahi, Mauricio F; Wang, Minghui; Pradeep, Chullikkattil P; Li, Feng-Yan; Lydon, Claire; Xu, Lin; Cronin, Leroy; Liu, Tianbo

2011-08-01

126

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

NASA Astrophysics Data System (ADS)

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.

Imam, Hisham; Elsayed, Khaled; Madkour, Fatma

2011-06-01

127

Inorganic Graphenylene: A Porous Two-Dimensional Material With Tunable Band Gap  

E-print Network

By means of ab initio calculations we investigate the possibility of existence of a boron nitride (BN) porous two-dimensional nanosheet which is geometrically similar to the carbon allotrope known as biphenylene carbon. The proposed structure, which we called Inorganic Graphenylene (IGP), is formed spontaneously after selective dehydrogenation of the porous Boron Nitride (BN) structure proposed by Ding et al. We study the structural and electronic properties of both porous BN and IGP and it is shown that, by selective substitution of B and N atoms with carbon atoms in these structures, the band gap can be significantly reduced, changing their behavior from insulators to semiconductors, thus opening the possibility of band gap engineering for this class of two-dimensional materials.

Perim, Eric; Atreto, Pedro Alves da Silva; Galvão, Douglas

2014-01-01

128

Cross-sectional TEM preparation of hybrid inorganic/organic materials systems by ultramicrotomy  

NASA Astrophysics Data System (ADS)

Preparation of hybrid inorganic-organic systems (HIOS) for transmission electron microscopy (TEM) in cross sectional view is the key for understanding the interfacial structure. Strikingly different materials properties like hardness, cleavability and heat sensitivity limit the number of applicable preparation strategies. Successful preparation of a HIOS system combining ZnO and para-sexiphenyl (6P) is realized by ultramicrotomy. It is shown that the alignment of the cutting plane with respect to the (0001) cleavage plane of ZnO plays a decisive role for successful preparation of extended TEM lamellae and the preservation of the HIOS structure. In particular, for (0001) oriented ZnO substrates the optimum cut direction is parallel to the HIOS interface. In cross-sectional high-resolution TEM images (100) lattice planes of 6P are observed proving the appropriate preparation strategy.

Kirmse, H.; Oehlschlegel, E.; Polzer, F.; Blumstengel, S.; Sparenberg, M.; Henneberger, F.

2013-11-01

129

Retention of organic and inorganic chemicals by the drainage/supply piping material.  

PubMed

A critical issue facing the turfgrass industry is the environmental fate and transport of organic and inorganic chemicals used on golf courses. The fate and distribution of those chemicals are strongly influenced by sorptive interactions with soil and sediment. In this study, the drainage and water supply piping material (used for construction of a prototype encapsulated golf green) was utilized to determine its potential sorption of three organic chemicals [2,4-dichloro-phenoxyacetic acid] (2,4-D), naphthalene and toluene and nitrate. Crushed piping material (small-to-large particle sizes) was evaluated. Isotherms were constructed using a batch equilibration technique. The results showed that the drainage/supply piping material at small particle sizes (<2.5 mm) has higher sorptive ability compared to soil (1.7 for 2,4-D and 13.4 for naphthalene). The K(F) value was 44, 253 and 70 for 2,4-D, naphthalene and toluene, respectively. K(oc) values were much higher than those of peat and soil at lower equilibrium concentrations. However, sorption decreased dramatically with increasing particle size (approaching zero at particle size 10 mm), due to reduction of surface areas and sorption sites. Sorption of NO(3)-N by the piping material was negligible. We concluded that sorption by intact drainage/supply piping material would not affect the recycling efficiency of pesticides and nutrients in the constructed encapsulated green. Conversely, drainage/supply piping material particles smaller than 2.5 mm in diameter can effectively be utilized as a filtering material. PMID:15092935

Li, K; Torello, W A; Xing, B

2000-06-01

130

Synthesis of Inorganic-Organic Hybrid Materials Designed for Radiation Detection, Luminescence, and Gas Storage  

NASA Astrophysics Data System (ADS)

Materials discovery is the driving force behind the research presented herein. Basic research has been conducted in order to obtain a better understanding of coordination chemistry and structural outcomes, particularly within the area of trivalent lanthanides. Discovering new materials is one route to further advancement of technology; another one is the focus on incremental changes to already existing materials. Often the building blocks of a compound are chosen in an effort to synthesize a material that makes use of the properties of each individual component and may result in a better, more robust, applicable material. The combination of organic and inorganic components for the synthesis of novel materials with potential applications such as scintillation photoluminescence, catalysis, and gas storage are the focus of the research presented herein. The first part focuses on lanthanide organic hybrid materials, where the synthesis of a new family of potential scintillating materials was undertaken and yielded improved understanding of the control that can be achieved over the topological structure of these materials by controlling the coordinating crystallization solvents. This research has led to the synthesis of an array of unique motifs, ranging from dimeric complexes, tetrameric complexes, to 1-D chains, and most intriguing of all, catenated tetradecanuclear rings. These rings represent the largest lanthanide rings synthesized to date, the next largest multinuclear rings, until now, were dodecanuclear complexes of alkoxides. From a basic research standpoint this is an exciting new development in lanthanide coordination chemistry and illustrates the importance of steric effects upon a system. These complexes are potential scintillators, supported by their luminescence and measurements of similar compounds that demonstrate surprising scintillation efficiencies. In the second part, other hybrid materials that have also been prepared are discussed, including the synthesis of a polyoxometallate compound (POM) containing a typical Keggin ion, which is charge-balanced via protonated organic ligands. POMs are one of the most studied inorganic clusters owing to their potential catalytic capabilities. A third part concerns a pseudo hybrid material consisting of boron, a metalloid, and a polymeric network, which includes a site of contortion, provided by the incorporation of a disulfide linkage and polymerized through boronate ester linkages. Tuning of this disulfide-linked polymer of intrinsic microporosity has the potential to lead to a dynamic material that may have gas sorption properties. The fourth part describes research in which the goal was to synthesize novel metal organic frameworks (MOFs) for solid state lighting applications via the synthesis of long, rigid, highly conjugated ligands. The successful synthesis of these ligands and optimization of the reaction conditions through the use of cyano derivatives as intermediates was discovered. Subsequent incorporation into coordination polymers with the transition elements was unsuccessful. This is believed to be the case due to the rigidity of the ligands and their inability to be flexible enough to successfully coordinate to a metal cation in a crystalline form.

Vaughn, Shae Anne

131

Electrochemical properties of sulfur as cathode materials in a solid-state lithium battery with inorganic solid electrolytes  

Microsoft Academic Search

Sulfur was investigated as positive electrode materials for all-solid-state lithium batteries with an inorganic solid electrolyte a-60Li2S·40SiS2 (mol%). The sulfur (54 mass%) was ball-milled with metallic copper (42.8 mass%) and acetylene black (3.2 mass%) for 10 h and the obtained composite was used as the positive electrode materials of the solid-state battery. The composite worked as reversible positive electrode materials

Nobuya Machida; Kazuma Kobayashi; Yutaka Nishikawa; Toshihiko Shigematsu

2004-01-01

132

Remote pulsed Raman spectroscopy of inorganic and organic materials to a radial distance of 100 meters.  

PubMed

A portable pulsed remote Raman spectroscopy system has been fabricated and tested to 100 m radial distance. The remote Raman system is based on a directly coupled f/2.2 spectrograph with a small (125 mm diameter) telescope and a frequency-doubled Nd:YAG pulsed laser (20 Hz, 532 nm, 25 mJ/pulse) used as the excitation source in a co-axial geometry. The performance of the Raman system is demonstrated by measuring the gated Raman spectra of calcite, sodium phosphate, acetone, and naphthalene. Raman spectra of these materials were recorded with the 532 nm pulsed laser excitation and accumulating the spectra with 600 laser shots (30 s integration time) at 100 m with good signal-to-background ratio. The remote pulsed Raman system can be used for remotely identifying both inorganic and organic materials during daytime or nighttime. The system will be useful for terrestrial applications such as monitoring environmental pollution and for detecting minerals and organic materials such as polycyclic aromatic hydrocarbons (PAHs) on planetary surfaces such as Mars. PMID:16925922

Sharma, S K; Misra, A K; Lucey, P G; Angel, S M; McKay, C P

2006-08-01

133

Conceptual study of in-tank cesium removal using an inorganic ion exchange material  

SciTech Connect

Presently, the Hanford Site contains approximately 230,000 m{sup 3} of mixed waste stored in 177 underground tanks. Approximately 55,000 m{sup 3} of this waste is sludge, 90,000 m{sup 3} is salt cake, and 80,000 m{sup 3} is supernate. Although the pretreatment and final disposal requirements for the waste have not been entirely defined, it is likely that some supernatant pretreatment will be required to remove {sup 137}Cs and possibly {sup 90}Sr and the transuranic components. The objective of this study was to estimate the number of HLW glass canisters resulting from the use of inorganic ion exchanger materials as in-tank pretreatment technology. The variables in the study were: number of contacts between waste and ion exchange material; ion exchange material; and decontamination requirement. This conceptual study investigates a generic in-tank Cs removal flowsheet using crystalline silico-titanates and IE-96 zeolites, and the impact of each ion exchanger on the number of glass canisters produced. In determining glass formulation, data based on current reference technology was used. Sample calculations from the worksheets and summaries of final calculated results are included at the end of this report.

Goheen, R.S.; Kurath, D.E.

1996-04-01

134

Multifunctional hybrid organic-inorganic catalytic materials with a hierarchical system of well-defined micro- and mesopores.  

PubMed

Novel layered zeolitic organic-inorganic materials (MWW-BTEB) have been synthesized by intercalation and stabilization of arylic silsesquioxane molecules between inorganic zeolitic MWW layers. The organic linkers are conformed by two condensed silyl-arylic groups from disilane molecules, such as 1,4-bis(triethoxysilyl)benzene (BTEB), which react with the external silanol groups of the zeolitic layers. The hybrids contain micropores within the inorganic layers and a well-defined mesoporous system in between the organic linkers. An amination post-treatment introduces basic groups in the organic linkers close to the acid sites present in the structural inorganic counterpart. Through this methodology it has been possible to prepare bifunctional acid-base catalysts where the acid sites are of zeolitic nature located in the inorganic building blocks and the basic sites are part of the organic structure. The resultant materials can act as bifunctional catalysts for performing a two-step cascade reaction that involves the catalytic conversion of benzaldehyde dimethylacetal into benzylidene malononitrile. PMID:20879788

Corma, Avelino; Díaz, Urbano; García, Teresa; Sastre, Germán; Velty, Alexandra

2010-10-27

135

Stable and efficient organo-inorganic emitting materials: a new rare earth-MOF family  

NASA Astrophysics Data System (ADS)

New outstanding possibilities are emerging by the synthesis of organo-inorganic polymeric materials from a buildingblock approach. Our approach has been to assemble extended solids from bent flexible arenedicarboxylate linkers that offer totally new topologies with helical channels. A new family of Rare-earth Polymeric Framework (RPF-4) has been obtained and its structure solved. The framework is formed by a Lanthanide (Ln) matrix, with the Ln atoms well separated in two directions. The crystals are highly stable in air and the decomposition temperature is above 350°C. Under UV excitation, the linker presents a bluish-white emission peaking around 450 nm. The emission corresponding to the different crystals either present an emission similar to the linker, slightly modified depending on R, or an intense emission due to Ln localized crystal field transitions. In the second case, an energy transfer from the linker to the Ln ions, which relax radiatively with a very efficient emission, seems to occur. The observed emission properties and crystal stability are of interest for applications as light emitting materials. The peculiarities of the structure may avoid the concentration quenching of the luminescence since Ln ions form well separated chains along a-axis with interchain distances around 12.5 Å.

Gándara, F.; Snejko, N.; Martínez-Morillas, R.; de Andrés, A.; Coya, C.; Gutiérrez-Puebla, E.; Monge, M. A.

2008-04-01

136

Synthesis and characterization of two new photochromic inorganic-organic hybrid materials based on Keggin-type polyoxometalates  

Microsoft Academic Search

Two new photochromic inorganic-organic hybrid materials formed from Keggin-type polyoxometalates(POMs) and metronidazole (C6H9N3O3, MNZ), formulated as H3PMo12O40·3MNZ·3H2O(1) and H3PW12O40·3MNZ·3H2O(2), were synthesized and characterized by elemental analysis, IR spectra, electronic spectra, electron spin resonance (ESR)\\u000a spectra and thermogravi-metry-differential thermal analysis (TG-DTA). Reflectance spectra show the presence of weak intermolecular\\u000a charge transfer between the organic and inorganic moieties in the solid state.

Zongjun Ku; Surong Jin

2008-01-01

137

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

PubMed

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

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

2011-06-01

138

Lanthanide organic-inorganic hybrids based on functionalized metal-organic frameworks (MOFs) for a near-UV white LED.  

PubMed

A novel near-UV white LED based on lanthanide organic-inorganic hybrid material is realized through postsynthetically modified MOFs and MOF-based polymers. The hybrids materials have high quantum yield and satisfactory luminescence stability; the assembled white LED has tuneable correlated color temperature and high color rendering index. PMID:25352310

Lu, Ye; Yan, Bing

2014-12-18

139

Functional materials for rechargeable batteries.  

PubMed

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

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

2011-04-19

140

Reducing the thermal dependence of silica-based arrayed-waveguide grating using inorganic-organic hybrid materials  

Microsoft Academic Search

This study demonstrates the application of a temperature-independent arrayed-waveguide grating (AWG) using a simple hybrid waveguide structure composed of silica core\\/inorganic-organic hybrid material overcladding layer. The thermooptic effect of the hybrid materials varies over a wide range of temperature and provides athermal characteristics in an AWG. The temperature dependence of the AWG was reduced through the precision control of the

Eun-Seok Kang; Woo-Soo Kim; Duk-Jun Kim; Byeong-Soo Bae

2004-01-01

141

Investigation of the two-photon polymerisation of a Zr-based inorganic organic hybrid material system  

Microsoft Academic Search

Two-photon polymerisation of photo-sensitive materials allows the fabrication of three dimensional micro- and nano-structures for photonic, electronic and micro-system applications. However the usable process window and the applicability of this fabrication technique is significantly determined by the properties of the photo-sensitive material employed. In this study investigation of a custom inorganic organic hybrid system, cross-linked by a two-photon induced process,

B. Bhuian; R. J. Winfield; S. O'Brien; G. M. Crean

2006-01-01

142

Investigation of the two-photon polymerisation of a Zr-based inorganic–organic hybrid material system  

Microsoft Academic Search

Two-photon polymerisation of photo-sensitive materials allows the fabrication of three dimensional micro- and nano-structures for photonic, electronic and micro-system applications. However the usable process window and the applicability of this fabrication technique is significantly determined by the properties of the photo-sensitive material employed. In this study investigation of a custom inorganic–organic hybrid system, cross-linked by a two-photon induced process, is

B. Bhuian; R. J. Winfield; S. O’Brien; G. M. Crean

2006-01-01

143

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

NASA Astrophysics Data System (ADS)

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.

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

2006-12-01

144

Fractal Geometric Characterization of Functionally Graded Materials  

E-print Network

Fractal Geometric Characterization of Functionally Graded Materials A. Saharan1 ; M. Ostoja. Author keywords: Fractal; Fractal dimension; Functionally graded materials (FGM); Scale dependence, since the 1980s, there has been a major research effort on the so-called functionally graded materials

Ostoja-Starzewski, Martin

145

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

PubMed Central

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

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

2013-01-01

146

Molecular design of luminescent organic-inorganic hybrid materials activated by europium (III) ions  

NASA Astrophysics Data System (ADS)

Luminescent hybrid materials consisting in rare-earth (Eu 3+, Gd 3+) organic complexes covalently attached to a silica-based network have been obtained by a sol-gel process. Four dicarboxylic acids with different aromatic subunits (dipicolinic acid, 4-phenyl-2,6-pyridinedicarboxylic acid, 4-(phenylethynyl)-2,6-pyridinedicarboxylic acid and 2,6-Bis(3-carboxy-1-pyrazolyl)pyridine) have been chosen as ligands for Ln 3+ ions. They were grafted to 3-aminopropyltriethoxysilane (APTES) to give organically modified alkoxysilanes that were used as molecular precursors for the preparation of hybrid materials. Ln 3+ first coordination sphere, composition of the siloxane matrix and connection between the organic and inorganic parts have been characterized by infrared spectroscopy, by 13C 29Si solid-state NMR as well as by elemental analyses. UV excitation in the organic component resulted in strong emission from Eu 3+ ions due to an efficient ligand-to-metal energy transfer. As compared to reference organic molecules, hybrid samples exhibited similar emission properties under UV excitation in addition to mainly unchanged excited states lifetimes. However, by direct excitation of the Eu 3+- 5D 0 energy level, the presence of two different site distributions were evidenced in the four hybrid compounds. Emission features related to each of these site distributions and their respective attribution were investigated. Variations in the relative emission intensities were observed according to the nature of the organic chromophore. These variations were discussed in relation to the ATE (Absorption-Transfer-Emission) mechanism and to the relative energy positions of the ligand and the rare-earth ions respectively.

Franville, Anne-Christine; Mahiou, Rachid; Zambon, Daniel; Cousseins, Jean-Claude

2001-02-01

147

The performance of organic and inorganic coated retort pouch materials on the shelf life of ready-to-eat rice products  

Microsoft Academic Search

The performance of organic and inorganic coated retort pouch materials on the shelf life of ready-to-eat (RTE) rice products was investigated. Two different retort pouch structures were used: the organic material coated retort pouch (ORG), organic material coated polyethylene terephthalate (PET)\\/biaxially oriented nylon (BON)\\/cast polypropylene (CPP); the inorganic material coated retort pouch (IND), aluminum oxide coated PET\\/BON\\/CPP. Two specific cooked

Youngjae Byun; Seung In Hong; Sunil Mangalassary; Ho Jae Bae; Kay Cooksey; Hyun Jin Park; Scott Whiteside

2010-01-01

148

Biodegradable and biocompatible inorganic-organic hybrid materials: 2. Dynamic mechanical properties, structure and morphology  

Microsoft Academic Search

Dynamic mechanical properties, structure and morphology of tetraethoxysilane\\/poly(?-caprolactone) (TEOS\\/PCL) hybrid materials have been analysed by dynamic mechanical spectroscopy, small-angle X-ray scattering, transmission electron microscopy, and image analysis. The experimental observations agree with a microscopic phase separation of the two constitutive components: the organic polymer and the silica network. The effect of the PCL functional end-groups, the number of functional end-groups

D. Tian; S. Blacher; Ph. Dubois; R. Jérôme

1998-01-01

149

Inorganic-organic hybrid materials and abrasion resistant coatings based on a sol-gel approach  

Microsoft Academic Search

Attempts to synthesize hybrid materials from polytetramethylene oxide (PTMO) end-functionalized with triethoxy silyl groups and, tetraethylorthosilicate (TEOS) under basic conditions met with only partial success. The films obtained had low mechanical stability. In contrast, films with good mechanical stability were obtained when the TEOS was replaced with tritanium tetraisopropoxide (TIOPR). The microstructure of the TIOPR\\/PTMO hybrid synthesized under near neutral

Betrabet

1993-01-01

150

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

NASA Technical Reports Server (NTRS)

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.

Talham, Daniel R.; Adair, James H.

1999-01-01

151

Thickness dependence of the photoinduced birefringence in azodye-doped inorganic organic hybrid materials by a femtosecond laser  

Microsoft Academic Search

The kinetics of the photoinduced birefringence (PB) induced by a femtosecond laser through two-photon absorption was studied in bulk azodye-doped inorganic-organic hybrid materials derived from the sol-gel method. The effects of the sample thickness on the kinetics of the PB were investigated. The probe transmittance for the saturated PB considerably increased and saturated with increasing the thickness, while the effects

Jiayu Guo; Jinhai Si; Guodong Qian; Jifeng Zu; Jianrong Qiu; Minquan Wang; Kazuyuki Hirao

2006-01-01

152

Functionalization and post-functionalization: a step towards polyoxometalate-based materials.  

PubMed

Polyoxometalates (POMs) have remarkable properties and a great deal of potential to meet contemporary societal demands regarding health, environment, energy and information technologies. However, implementation of POMs in various functional architectures, devices or materials requires a processing step. Most developments have considered the exchange of POM counterions in an electrostatically driven approach: immobilization of POMs on electrodes and other surfaces including oxides, embedding in polymers, incorporation into Layer-by-Layer assemblies or Langmuir-Blodgett films and hierarchical self-assembly of surfactant-encapsulated POMs have thus been thoroughly investigated. Meanwhile, the field of organic-inorganic POM hybrids has expanded and offers the opportunity to explore the covalent approach for the organization or immobilization of POMs. In this critical review, we focus on the use of POM hybrids in selected fields of applications such as catalysis, energy conversion and molecular nanosciences and we endeavor to discuss the impact of the covalent approach compared to the electrostatic one. The synthesis of organic-inorganic POM hybrids starting from bare POMs, that is the direct functionalization of POMs, is well documented and reliable and efficient synthetic procedures are available. However, as the complexity of the targeted functional system increases a multi-step strategy relying on the post-functionalization of preformed hybrid POM platforms could prove more appealing. In the second part of this review, we thus survey the synthetic methodologies of post-functionalization of POMs and critically discuss the opportunities it offers compared to direct functionalization. PMID:22782306

Proust, Anna; Matt, Benjamin; Villanneau, Richard; Guillemot, Geoffroy; Gouzerh, Pierre; Izzet, Guillaume

2012-11-21

153

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

SciTech Connect

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.

Huang Jing [College of Chemistry and Chemical Engineering Southwest University, Research Institute of Applied Chemistry Southwest University, Key Laboratory of Applied Chemistry of Chongqing Municipality, Key Laboratory of Eco-environments in Three Gorges Reservoir Region Ministry of Education, Chongqing 400715 (China); Fu Xiangkai, E-mail: fxk@swu.edu.cn [College of Chemistry and Chemical Engineering Southwest University, Research Institute of Applied Chemistry Southwest University, Key Laboratory of Applied Chemistry of Chongqing Municipality, Key Laboratory of Eco-environments in Three Gorges Reservoir Region Ministry of Education, Chongqing 400715 (China); Wang Gang; Miao Qiang [College of Chemistry and Chemical Engineering Southwest University, Research Institute of Applied Chemistry Southwest University, Key Laboratory of Applied Chemistry of Chongqing Municipality, Key Laboratory of Eco-environments in Three Gorges Reservoir Region Ministry of Education, Chongqing 400715 (China)

2011-09-15

154

Sensors for inorganic vapor detection based on carbon nanotubes and poly( o-anisidine) nanocomposite material  

NASA Astrophysics Data System (ADS)

A gas sensor, fabricated by selective growth of aligned carbon nanotubes (CNTs) by pulsed plasma on Si 3N 4/Si substrates patterned by metallic platinum, is presented for inorganic vapor detection at room temperature. Poly( o-anisidine) (POAS) deposition onto the CNTs device was shown to impart higher sensitivity to the sensor. Upon exposure to HCl the variation of the CNTs sensitivity is less than 4%, while the POAS-coated CNTs devices offer a higher sensitivity (i.e. 28%). The extended detection capability to inorganic vapors is attributed to direct charge transfer with electron hopping effects on intertube conductivity through physically adsorbed POAS between CNTs.

Valentini, L.; Bavastrello, V.; Stura, E.; Armentano, I.; Nicolini, C.; Kenny, J. M.

2004-01-01

155

Silica-Based and Transition Metal-Based Inorganic-Organic Hybrid Materials—A Comparison  

Microsoft Academic Search

Organically substituted metal alkoxides can be prepared by reaction of the parent alkoxides with complexing organic compounds. The chemical and structural consequences of such substitutions are discussed in this article. Examples are given showing how functional organic moieties, such as polymerizable groups, can be incorporated into sol-gel materials via the complexing ligands. Major structural differences between silica-based and metal-based hybrid

Ulrich Schubert

2003-01-01

156

Novel layered crystalline organic polymer-inorganic hybrid material comprising calcium phosphate with unique architectures for superior performance catalyst support.  

PubMed

An organic copolymer-inorganic hybrid material, calcium phosphonate-phosphate (CaPS-PVPA), is fabricated under mild conditions. In particular, CaPS-PVPA is not prepared with traditional methods such as a hydrothermal one, but with amorphous reactions for a simple, fast, cost-effective and environmentally benign approach. Characterization shows that CaPS-PVPA is a layered crystalline mesoporous material, and could be readily used as a catalytic support. A catalyst with immobilization of chiral salen Mn(iii) onto CaPS-PVPA demonstrate a superior catalytic disposition (conv. > 99% and ee > 99%), which offers great potential for industry scale applications. PMID:25340324

Huang, Jing; Tang, Mei; Li, Xin; Zhong, Guo Zhen; Li, Chang Ming

2014-11-01

157

Reconstruction strategies for structure solution using precession electron diffraction data from hybrid inorganic-organic framework materials  

NASA Astrophysics Data System (ADS)

Precession electron diffraction has received significant recent attention, and has the potential to complement x-ray structure solution methods in situations where the latter are difficult to apply. Certain materials systems may nevertheless present challenges for solution by electron diffraction, and this is particularly true when the unit cell includes light element components. Drawing specifically on our work with hybrid inorganic-organic framework materials, we describe recent approaches to reconstructing their crystal potentials, which have led to significant improvements in the accuracy and quality of the derived potential maps for this type of structure.

Bithell, E. G.; Merrill, C. A.; Midgley, P. A.

2010-07-01

158

Organofunctional Metal Oxide Clusters as Building Blocks for Inorganic-Organic Hybrid Materials  

Microsoft Academic Search

The controlled hydrolysis of metal alkoxides in the presence of methacrylic acid results in metal oxide clusters capped by polymerizable methacrylate ligands. Radical polymerization of small portions of such clusters with organic co-monomers allows the preparation of an interesting new type of inorganic-organic hybrid polymers in which the metal oxo clusters efficiently crosslink the organic polymers chains. SAXS investigations revealed

Ulrich Schubert

2004-01-01

159

Remote Raman Spectroscopic Detection of Inorganic, Organic and Biological Materials to 100 m and More  

NASA Astrophysics Data System (ADS)

We have designed and tested a portable gated-Raman system that is capable of detecting organic and inorganic bulk chemicals over stand-off distances of 100 m and more during day and night time. Utilizing a 532 nm laser pulse (~35 mJ/pulse), Raman spectra of several organic and inorganic compounds have been measured with the portable Raman instrument over a distance of 100 m. Remote Raman spectra, obtained with a very short gate (2 micro second), from a variety of inorganic minerals such as calcite (CaCO3), ?-quartz (?-SiO2), barite (BaSO4), and FeSO4.7H2O, and organic compounds such as acetone, methanol, 2-propanol and naphthalene showed all major bands required for unambiguous chemical identification. We also measured the Raman and fluorescence spectra of plant leaves, tomato, and chicken eggshell excited with a 532 nm, 20 Hz pulsed laser and accumulated over 200 laser shots (10-s integration time) at 110 m with good signal-to-noise ratio. The results of these investigations show that remote Raman spectroscopy over a distance of 100 m can be used to identify Raman fingerprints of both inorganic, organic, and some biological compounds on planetary surfaces and could be useful for environmental monitoring.

Sharma, Shiv K.; Misra, Anupam K.

2008-11-01

160

Photoactive hybrids with the functionalized Schiff-base derivatives covalently bonded inorganic silica network: Sol–gel synthesis, characterization and photoluminescence  

Microsoft Academic Search

Three novel silica-based organic–inorganic hybrid materials containing the different Schiff-base organic compounds have been prepared through a covalent bonding self-assembly process via a sol–gel technology. The organic parts N,N?-bis(salicylidene)-1,3-propanediamine, N,N?-bis(salicylidene)-thiocarbohydrazide, and N,N?N??-tris(salicylidene)-(2-aminoethyl) amine are firstly synthesized and then functionalized by trialkoxysilyl groups through the hydrogen transfer reaction. The as-obtained silylated precursors are afterward submitted to hybridization with tetraethoxysilane (TEOS) through

Jin-Liang Liu; Shuai Xu; Bing Yan

2011-01-01

161

UV-patternable inorganic-organic hybrid materials tailored for use in electro-optic modulators  

NASA Astrophysics Data System (ADS)

Passive sol-gel materials play an important role in the development of electro-optic(EO) polymer-based modulators, because of their variety of available refractive indices. They can be used to form passive waveguide transitions to minimize coupling loss or as cladding layers for the EO polymer. The demands for these two applications are different. For waveguide transitions the most important factor is the optical loss. Cladding layers should have a relatively high conductivity at elevated temperatures to improve poling efficiency. Both demands are addressed in this study. The synthesis of low loss (down to 0.45 dB/cm) sol-gel materials is shown. Slab waveguides as well as ridge waveguides were fabricated and characterized by liquid prism measurements and cut-back loss measurements, respectively. For use in cladding layers surrounding the EO polymer, materials with higher conductivity were developed. The conductivity of the materials was increased, (3•10-9 S/m) through the use of a silane, which allows in situ formation of proton donating functionalities. All developed materials can be used as solvent free resins, which enables classic photolithography as well as patterning by UV-imprinting. The available refractive index range (at 1.55 ?m) is from 1.495 to 1.562.

Himmelhuber, Roland; DeRose, Christopher C.; Norwood, Robert A.; Peyghambarian, Nasser

2008-08-01

162

Electrohydrodynamic Patterning of Functional Materials  

E-print Network

and characteristic length scales of patterns formed in thin films along with their applications are explained. Each of the following six chapters is devoted to a different material or set of ma- terials patterned via EHD method, followed by the discussion... discussed. These findings evolve as very promising to be truly exploited in optoelectronic and photovoltaic devices. Finally, the thesis concludes with Chapter 10 summarizing the experimental out- comes and applications. The intriguing aspects of physics...

Goldberg Oppenheimer, Pola

2014-05-27

163

Environmental degradation using functionally graded material approach  

E-print Network

Environmental degradation using functionally graded material approach I. Sevostianov a,*, N of the laminate. Ã? 2003 Elsevier Ltd. All rights reserved. Keywords: Degradation; Functionally graded; Microcracks and combine the properties of the damaged and undamaged layer to obtain bulk material properties

Sevostianov, Igor

164

Laser-induced breakdown spectroscopy (LIBS) technique for the determination of the chemical composition of complex inorganic materials  

NASA Astrophysics Data System (ADS)

Laser-induced breakdown spectroscopy (LIBS) is a fast, fully optical method, that needs little or no sample preparation. In this technique qualitative and quantitative analysis is based on comparison. The determination of composition is generally based on the construction of a calibration curve namely the LIBS signal versus the concentration of the analyte. Typically, to calibrate the system, certified reference materials with known elemental composition are used. Nevertheless, such samples due to differences in the overall composition with respect to the used complex inorganic materials can influence significantly on the accuracy. There are also some intermediate factors which can cause imprecision in measurements, such as optical absorption, surface structure, thermal conductivity etc. This paper presents the calibration procedure performed with especially prepared pellets from the tested materials, which composition was previously defined. We also proposed methods of post-processing which allowed for mitigation of the matrix effects and for a reliable and accurate analysis. This technique was implemented for determination of trace elements in industrial copper concentrates standardized by conventional atomic absorption spectroscopy with a flame atomizer. A series of copper flotation concentrate samples was analyzed for contents of three elements, that is silver, cobalt and vanadium. It has been shown that the described technique can be used to qualitative and quantitative analyses of complex inorganic materials, such as copper flotation concentrates.

?azarek, ?ukasz; Anto?czak, Arkadiusz J.; Wójcik, Micha? R.; Kozio?, Pawe? E.; Stepak, Bogusz; Abramski, Krzysztof M.

2014-08-01

165

Synthesis and properties of soft nanocomposite materials with novel organic\\/inorganic network structures  

Microsoft Academic Search

We have fabricated new types of polymer hydrogels and polymer nanocomposites, that is, nanocomposite gels (NC gels) and soft polymer nanocomposites (M-NCs), with novel organic\\/inorganic network structures. Both NC gels and M-NCs were synthesized by in situ free-radical polymerization in the presence of exfoliated clay platelets in aqueous systems and were obtained in various forms and sizes with a wide

Kazutoshi Haraguchi

2011-01-01

166

Sensors for inorganic vapor detection based on carbon nanotubes and poly( o-anisidine) nanocomposite material  

Microsoft Academic Search

A gas sensor, fabricated by selective growth of aligned carbon nanotubes (CNTs) by pulsed plasma on Si3N4\\/Si substrates patterned by metallic platinum, is presented for inorganic vapor detection at room temperature. Poly(o-anisidine) (POAS) deposition onto the CNTs device was shown to impart higher sensitivity to the sensor. Upon exposure to HCl the variation of the CNTs sensitivity is less than

L. Valentini; V Bavastrello; E Stura; I Armentano; C Nicolini; J. M Kenny

2004-01-01

167

Inorganically filled starch based fiber reinforced composite foam materials for food packaging  

Microsoft Academic Search

A process for the manufacture of highly inorganically filled starch based fiber reinforced foam composites for food-packaging\\u000a use is described. Starch, obtained from potato, corn, or other sources, is used as binder to form net shape foam composite\\u000a substrates under hydrothermal conditions. The starch content is 25 to 60 wt. % of the product. Ground calcium carbonate is\\u000a the principal

Per Just Andersen; A. Kumar; Simon K. Hodson

1999-01-01

168

Attenuation of landfill leachate by UK Triassic sandstone aquifer materials. 1. Fate of inorganic pollutants in laboratory columns  

NASA Astrophysics Data System (ADS)

The attenuation of inorganic contaminants in acetogenic and methanogenic landfill leachate by calcareous and carbonate-deficient, oxide-rich Triassic sandstone aquifer materials from the English Midlands was examined in laboratory columns. Aqueous equilibrium speciation modelling, simple transport modelling and chemical mass balance approaches are used to evaluate the key processes and aquifer geochemical properties controlling contaminant fate. The results indicate that leachate-rock interactions are dominated by ion-exchange processes, acid-base and redox reactions and sorption/precipitation of metal species. Leachate NH 4 is attenuated by cation exchange with the aquifer sediments; however, NH 4 migration could be described with a simple model using retardation factors. Organic acids in the acetogenic leachate buffered the system pH at low levels during flushing of the calcareous aquifer material. In contrast, equilibrium with Al oxyhydroxide phases initially buffered pH (˜4.5) during flushing of the carbonate-deficient sandstone with methanogenic leachate. This led to the mobilisation of sorbed and oxide-bound heavy metals from the aquifer sediment which migrated as a concentrated pulse at the leachate front. Abiotic reductive dissolution of Mn oxyhydroxides on each aquifer material by leachate Fe 2+ maintains high concentrations of dissolved Mn and buffers the leachate inorganic redox system. This feature is analogous to the Mn-reducing zones found in leachate plumes and in the experiments provides a sink for the leachate Fe load and other heavy metals. The availability of reactive solid phase Mn oxyhydroxides limits the duration of redox buffering and Fe attenuation by these aquifer sediments. Aquifer pH and redox buffering capacity exert a fundamental influence on leachate inorganic contaminant fate in these systems. The implications for the assessment of aquifer vulnerability at landfills are discussed and simple measurements of aquifer properties which may improve the prediction of contaminant attenuation are outlined.

Thornton, Steven F.; Tellam, John H.; Lerner, David N.

2000-05-01

169

Polyester-inorganic nanocomposite materials via sol-gel reactions: Synthesis and characterization of fundamental properties  

NASA Astrophysics Data System (ADS)

A scheme was developed for producing poly(ethylene terephthalate (PET) ionomer)/silicate hybrid materials via polymer-in situ sol-gel reactions for tetraethylorthosilicate (TEOS) using different solvents. Scanning electron microscopy/EDAX studies revealed that silicate structures can be grown deep within PET ionomer films that were melt pressed from silicate-incorporated resin pellets. 29Si solid-state NMR spectroscopy revealed considerable, successful Si-O-Si bond formation, but also a significant fraction of uncondensed SiOH groups. 23Na solid-state NMR spectra suggested the presence of ionic aggregates within the unfilled PET ionomer and that these aggregates do not suffer major structural re-arrangements by silicate incorporation. For an ionomer treated with TEOS using MeCl2 solvent, Na + ions are less self-associated than in the unfilled control, suggesting silicate intrusion between PET-SO3- Na + ion pair associations. The ionomer treated with TEOS + tetrachloroethane had more poorly formed ionic aggregates, which illustrates the influence of solvent type on ionic aggregation. First-scan DSC thermograms for the ionomers demonstrate an increase in crystallinity after the incorporation of silicates, but solvent induced crystallization also appears to be operative. Second-scan DSC thermograms also suggest that the addition of silicate particles is not the only factor implicated in re-crystallization, and that solvent type is important even in second scan behavior. Silicate incorporation does not profoundly affect the second scan Tg vs. solvent type, i.e., chain mobility in the amorphous regions is not severely restricted by silicate incorporation. Re-crystallization and melting in these hybrids appears to be due to an interplay between a solvent induced crystallization that strongly depends on solvent type, and interactions between PET chains and in situ-grown, sol-gel-derived silicate particles. Isothermal studies confirmed that the crystallization rate and melting behavior of PET 5% Na+ ionomers depend on processing conditions. PET ionomer/ORMOSIL composites were formed via in situ sol-gel reactions using the ionic regions of PET as preferential reaction sites. TGA analysis revealed successful uptake for all three different solvents and TEOS:MTES composition ratios. TGA derivative curves suggest that for the THF and MeCl2 carrier solvent systems the MTES-generated network interacts more with the PET ionomer matrix. In the case of TCE, the TEOS-generated network interaction appears to be more operative. First scan DSC traces reveal that the in situ sol-gel processing of ORMOSIL phases induces PET ionomer crystallinity, although systems with higher silicate uptake have reduced induced crystallinity. Second scan DSC traces show that Tg is not effected by the incorporation of silicates into the PET ionomer. Also, for the ORMOSIL phases generated using THF and MeCl2 as the swelling solvent, only the pure silicate networks (synthesized using only TEOS) allow recrystallization and melting during the quick scan timeframe. It is thought that the presence of semi-organic MTES silicate networks do not allow fast nucleation onto the inorganic nuclei. (Abstract shortened by UMI.)

Lambert, Alexander Adam, III

170

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

Microsoft Academic Search

Two novel inorganic–organic hybrid materials based on an organic dye cation methylene blue (MB) and Lindqvist-type POM polyanions, [C22H18N3S]2Mo6O19 2DMF (1) and [C22H18N3S]2W6O19 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

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

2010-01-01

171

Oxyfunctionalisation of adamantane using inorganic–organic hybrid materials based on isopoly and heteropoly anions: Kinetics and mechanistic studies  

Microsoft Academic Search

Oxyfunctionalisation of adamantane with 30% aq.H2O2 in butyronitrile solvent was efficiently catalyzed by inorganic–organic hybrid materials synthesized by the immobilisation of isopoly (WOx=sodium tungstate, MoOx=sodium molybdate and VOx=sodium metavanadate) and heteropoly anions (V1=H4[PMo11VO40]·32·5H2O,and V3=H6[PMo9V3O40]·34H2O, STA=silicotungstic acid, TPA=tungstophosphoric acid and MPA=molybdophosphoric acid) onto mesoporous silica (SBA-15). These catalysts were well characterized by standard techniques and it was found that polyoxometalate has

Ankur Bordoloi; Ajayan Vinu; S. B. Halligudi

2007-01-01

172

Organic-inorganic electronics  

Microsoft Academic Search

Organic-inorganic hybrid materials enable the integration of useful organic and inorganic characteristics within a single molecular-scale composite. Unique electronic and optical properties have been observed, and many others can be envisioned for this promising class of materials. In this paper, we review the crystal structures and physical properties of one family of crystalline, self-assembling, organic-inorganic hybrids based on the layered

David B. Mitzi; Konstantinos Chondroudis; Cherie R. Kagan

2001-01-01

173

Boundary Element Methods for Functionally Graded Materials  

NSDL National Science Digital Library

Functionally graded materials (FGMs) possess a smooth variation of material properties due to continuous change in microstructural details. For example, the material gradation may change gradually from a pure ceramic to a pure metal. This work focuses on potential (both steady state and transient) and elasticity problems for inhomogeneous materials. The Green\\'s function(GF) for these materials (e.g. exponentially graded) are expressed as the GF for the homogeneous material plus additional terms due to material gradation. The numerical implementations are performed using a Galerkin (rather than collocation) approximation. A number of examples have been carried out. The results of some specific test problems agree within plotting accuracy with available analytical solutions.

Paulino, Glaucio; Sutradhar, Alok; Gray, L. J.

2002-05-28

174

Bridged polysilsesquioxanes: A molecular based approach for the synthesis of functional hybrid materials  

SciTech Connect

Bridged polysilsesquioxanes (BPS) are a family of hybrid organic-inorganic materials prepared by sol-gel polymerization of molecular building blocks that contain a variable organic component and at least two trifunctional silyl groups. The resulting xerogels and aerogels have physical and mechanical properties that are strongly influenced by the organic bridging group. This talk focuses on the synthesis of functional bridged polysilsesquioxanes. Incorporation of functional groups that respond to chemical, photochemical, or thermal stimuli can provide handles for modifying bulk morphology and/or provide function. These materials can find use as ion exchange media, chromatographic stationary phases, photoresists and high capacity selective chemical absorbents.

SHEA,KENNETH J.; LOY,DOUGLAS A.

2000-05-09

175

Rapid synthesis of a versatile organic/inorganic hybrid material based on pyrogenic silica.  

PubMed

An efficient approach has been developed to synthesize a new versatile organo-silica material by non-conventional method (microwave irradiation and ultrasonic vibration) from amorphous pyrogenic silica and has been compared with thermic procedure. The samples were fully characterized by FTIR, solid-state (29)Si and (13)C CP/MAS NMR, thermogravimetric analysis (TGA), elemental analysis, scanning electron microscopy (SEM) and by N(2)-sorption isotherms measurements. The functionalization of silicon dioxide by 4-(chloromethylphenyl) trichlorosilane has been easily achieved by ultrasound irradiation in a very short time with high loading of organic fragments. Significant different sizes of pores were observed according to conventional or non-conventional synthesis procedure. In addition, new structural properties have been created with the emergence of a mesoporosity. PMID:20580377

Becuwe, M; Cazier, F; Woisel, P; Landy, D; Delattre, F

2010-10-01

176

U.S./Russian lab-to-lab materials protection, control and accounting program efforts at the Institute of Inorganic Materials. Revision 1  

SciTech Connect

The All-Russian Scientific Research Institute of Inorganic Materials (VNIINM) performs research in nuclear power reactor fuel, spent fuel reprocessing and waste management, materials science of fissionable and reactor structural materials, metallurgy, superconducting materials, and analytical sciences. VNIINM supports the Ministry of Atomic Energy of the Russian Federation (MINATOM) in technologies for fabrication and processing of nuclear fuel. As a participant in the US/Russian Lab-to-Lab nuclear materials protection, control and accounting (MPC and A) program, VNIINM is providing support for measurements of nuclear materials in bulk forms by developing specifications, test and evaluation, certification, and implementation of measurement methods for such materials. In 1996, VNIINM will be working with Brookhaven staff in developing and documenting material control and accounting requirements for nuclear materials in bulk form, Livermore and Los Alamos staff in testing and evaluating gamma-ray spectrometry methods for bulk materials, Los Alamos staff in test and evaluation of neutron-coincidence counting techniques, Oak Ridge staff in accounting of bulk materials with process instrumentation, and Pacific Northwest staff on automating VNIINM`s coulometric titration system. In addition, VNIINM will develop a computerized accounting system for nuclear material within VNIINM and their storage facility. The paper will describe the status of this work and anticipated progress in 1996.

Ruhter, W.D. [Lawrence Livermore National Lab., CA (United States); Kositsyn, V.; Rudenko, V. [A.A. Bochvar`s All-Russian Scientific Research Inst. of Inorganic Materials, Moscow (Russian Federation); Siskind, B.; Bieber, A. [Brookhaven National Lab., Upton, NY (United States); Hoida, Hiroshi; Augustson, R. [Los Alamos National Lab., NM (United States); Ehinger, M. [Oak Ridge National Lab., TN (United States); Smith, B.W. [Pacific Northwest National Lab., Richland, WA (United States)

1996-07-24

177

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

PubMed

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 microm 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 river between Bend Bridge and Colusa. Analysis of temporal variations showed that Hg loading was positively correlated to discharge. PMID:11243317

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

2001-02-01

178

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

USGS Publications Warehouse

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.

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

2001-01-01

179

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

NASA Astrophysics Data System (ADS)

Two novel inorganic-organic hybrid materials based on an organic dye cation methylene blue (MB) and Lindqvist-type POM polyanions, [C 22H 18N 3S] 2Mo 6O 19 2DMF (1) and [C 22H 18N 3S] 2W 6O 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¯. Their crystal structures present that the layers of organic molecules and inorganic anions array alternatively, and there exist strong ?···? 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.

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

2010-12-01

180

U.S./Russian lab-to-lab materials protection, control and accounting program efforts at the Institute of Inorganic Materials  

SciTech Connect

The All-Russian Scientific Research Institute of Inorganic Materials (VNIINM) performs research in nuclear power reactor fuel,m spent fuel reprocessing and waste management, materials science of fissionable and reactor structural materials, metallurgy, superconducting materials, and analytical sciences. VNIINM supports the Ministry of Atomic Energy of the Russian Federation (MINATOM) in technologies for fabrication and processing of nuclear fuel. As a participant in the U. S./Russian Lab-to-Lab nuclear materials protection, control and accounting (MPC&A) program, VNIINM is providing evaluation, certification, and implementation of measurement methods for such materials. In 1966, VNIINM will be working with Brookhaven staff in developing and documenting material control and accounting requirements for nuclear materials in bulk form, Livermore and Los Alamos staff in testing and evaluating gamma-ray spectrometry methods for bulk materials, Los Alamos staff in test and evaluation of neutron-coincidence counting techniques, Oak Ridge staff in accounting of bulk materials with process instrumentation, and Pacific Northwest staff on automating VNIINM`s coulometric titration system. In addition, VNIINM will develop a computerized accounting system for nuclear material within VNIINM and heir storage facility. This paper describes the status of this work and anticipated progress in 1996.

Ruhter, W.D. [Lawrence Livermore National Lab., CA (United States); Kositsyn, V.; Rudenko, V. [Vsesoyuznyj Nauchno-Issledovatel`skij Inst. Neorganicheskikh Materialov, Moscow (Russian Federation); Siskind, B.; Bieber, A. [Brookhaven National Lab., Upton, NY (United States); Hoida, H.; Augustson, [Los Alamos National Lab., NM (United States); Ehinger, M. [Oak Ridge National Lab., TN (United States); Smith, B.W. [Pacific Northwest Lab., Richland, WA (United States)

1996-07-08

181

Functionally graded materials: Design, processing and applications  

SciTech Connect

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.

Miyamoto, Y. [ed.] [Osaka Univ. (JP); Kaysser, W.A.; Rabin, B.H.; Kawasaki, A.; Ford, R.G. [eds.

1999-09-01

182

Continuous spray forming of functionally gradient materials  

SciTech Connect

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.

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

1995-12-01

183

Hydrothermal synthesis and characterization of two novel inorganic-organic hybrid materials  

Microsoft Academic Search

By using different organic ligands, two 3D inorganic-organic hybrid compounds Co(C4H4N2)(VO3)2\\u000a 1 and Co(C12H12N2)(VO3)2\\u000a 2 were synthesized by hydrothermal reaction and characterized by X-ray crystallography. Crystal data: 1. crystal system orthorhombic, space group Pnna, a=10.188(2) Å, b=11.497(2) Å, c=7.3975(15) Å, V=866.5(3) Å3, Z=4, D\\u000a calcd=2.705 g\\/cm3; 2. crystal system triclinic, space group P\\u000a 1\\u000a ? (No. 2), a=8.3190(17) Å, b=8.4764(17)

Zeng-he Li; Hai-dan Bai

2008-01-01

184

Polyfunctional inorganic-organic hybrid materials: an unusual kind of NLO active layered mixed metal oxalates with tunable magnetic properties and very large second harmonic generation.  

PubMed

Mixed M(II)/M(III) metal oxalates, as "stripes" connected through strong hydrogen bonding by para-dimethylaminobenzaldeide (DAMBA) and water, form an organic-inorganic 2D network that enables segregation in layers of the cationic organic NLO-phore trans-4-(4-dimethylaminostyryl)-1-methylpyridinium, [DAMS+]. The crystalline hybrid materials obtained have the general formula [DAMS]4[M2M'(C2O4)6].2DAMBA.2H2O (M = Rh, Fe, Cr; M' = Mn, Zn), and their overall three-dimensional packing is non-centrosymmetric and polar, therefore suitable for second harmonic generation (SHG). All the compounds investigated are characterized by an exceptional SHG activity, due both to the large molecular quadratic hyperpolarizability of [DAMS+] and to the efficiency of the crystalline network which organizes [DAMS+] into head-to-tail arranged J-type aggregates. The tunability of the pairs of metal ions allows exploiting also the magnetic functionality of the materials. Examples containing antiferro-, ferro-, and ferri-magnetic interactions (mediated by oxalato bridges) are obtained by coupling proper M(III) ions (Fe, Cr, Rh) with M(II) (Mn, Zn). This shed light on the role of weak next-nearest-neighbor interactions and main nearest-neighbor couplings along "stripes" of mixed M(II)/M(III) metal oxalates of the organic-inorganic 2D network, thus suggesting that these hybrid materials may display isotropic 1D magnetic properties along the mixed M(II)/M(III) metal oxalates "stripes". PMID:17616190

Cariati, Elena; Macchi, Roberto; Roberto, Dominique; Ugo, Renato; Galli, Simona; Casati, Nicola; Macchi, Piero; Sironi, Angelo; Bogani, Lapo; Caneschi, Andrea; Gatteschi, Dante

2007-08-01

185

ATR-FTIR characterization of organic functional groups and inorganic ions in ambient aerosols at a rural site  

NASA Astrophysics Data System (ADS)

An Attenuated Total Reflectance-Fourier Transform Infrared (ATR-FTIR) spectroscopic method was used to measure organic functional groups and inorganic ions at Tonto National Monument (TNM), an Interagency Monitoring of Protected Visual Environments (IMPROVE) sampling site in a rural area near Phoenix, Arizona. Functional groups and ions from common aerosol compound classes such as aliphatic and aromatic CH, methylene, methyl, aldehydes/ketones, carboxylic acids, ammonium sulfate and nitrate as well as functional groups from difficult to measure compound classes such as esters/lactones, acid anhydrides, carbohydrate hydroxyl and ethers, amino acids, and amines were quantified. On average, ˜33% of the PM 1.0 mass was composed of organic aerosol. The average (standard deviation) composition of the organic aerosol at TNM was 34% (6%) biogenic functional groups, 21% (5%) oxygenated functional groups, 28% (7%) aliphatic hydrocarbon functional groups (aliphatic CH, methylene and methyl) and 17% (1%) aromatic hydrocarbon functional groups. Compositional analysis, functional group correlations, and back trajectories were used to identify three types of events with source signatures: primary biogenic-influenced, urban-influenced, and regional background. The biogenic-influenced event had high concentrations of amino acids and carbohydrate hydroxyl and ether, as well as aliphatic CH and aromatic CH functional groups and qualitatively high levels of silicate. The urban-influenced events had back trajectories traveling directly from the Phoenix area and high concentrations of hydrocarbons, oxygenated functional groups, and inorganic ions. This aerosol characterization suggests that both primary emissions in Phoenix and secondary formation of aerosols from Phoenix emissions had a major impact on the aerosol composition and concentration at TNM. The regional background source had low concentrations of all functional groups, but had higher concentrations of biogenic functional groups than the urban source.

Coury, Charity; Dillner, Ann M.

186

Synthesis and characterization of abrasion resistant coating materials prepared by the sol-gel approach: I. Coatings based on functionalized aliphatic diols and diethylenetriamine  

Microsoft Academic Search

The synthesis of inorganic organic hybrid materials has been undertaken and used as abrasion resistant coatings for polymeric substrates by the sol-gel method. The organic components are diethylenetriamine (DETA), glycerol, and a series of aliphatic diols which are functionalized by 3-isocyanatopropyltriethoxysilane. The inorganic components are tetramethoxysilane (TMOS), aluminum tri-see-butoxide, titaniumsec-butoxide and zirconiumn-propoxide. Solutions of these materials are spin coated onto

J. Wen; G. L. Wilkes

1995-01-01

187

Preparation of molecular imprinted microspheres based on inorganic-organic co-functional monomer for miniaturized solid-phase extraction of fluoroquinolones in milk.  

PubMed

An inorganic-organic co-functional monomer, methacrylic acid-vinyltriethoxysilan (MAA-VTES) was designed for the synthesis of molecularly imprinted microspheres (MIMs). By virtue of the aqueous suspension polymerization and dummy template (pazufloxacin), the obtained MAA-VTES based MIMs exhibited good recognition and selectivity to fluoroquinolones (FQs), and were successfully applied as selective sorbents of a miniaturized home-made solid phase extraction device for the determination of ofloxacin (OFL), lomefloxacin (LOM) and ciprofloxacin (CIP) in milk samples. Under the optimum conditions of the miniaturized molecularly imprinted solid phase extraction (mini-MISPE) coupled with liquid chromatography-ultraviolet detector (LC-UV), good linearities were obtained for three FQs in a range of 0.2-20.0?gmL(-1) and the average recoveries at three spiked levels were ranged from 87.2% to 106.1% with the relative standard deviation (RSD) less than 5.4%. The presented co-functional monomer based mini-MISPE-LC-UV protocol introduced the rigidity and flexibility of inorganic silicon materials, exhibited excellent extraction performance towards targets, and could be potentially applied to the determination of FQs in milk samples. PMID:24448515

Wang, Hui; Wang, Ruiling; Han, Yehong

2014-02-15

188

Functionalized SBA-15 materials for bilirubin adsorption  

NASA Astrophysics Data System (ADS)

To investigate the driving force for bilirubin adsorption on mesoporous materials, a comparative study was carried out between pure siliceous SBA-15 and three functionalized SBA-15 mesoporous materials: CH 3-SBA-15 (MS), NH 2-SBA-15 (AS), and CH 3/NH 2-SBA-15 (AMS) that were synthesized by one-pot method. The obtained materials exhibited large surface areas (553-810 m 2/g) and pore size (6.6-7.1 nm) demonstrated by XRD and N 2-ad/desorption analysis. The SEM images showed that the materials had similar fiberlike morphology. The functionalization extent was calculated according to 29Si MAS NMR spectra and it was close to the designed value (10%). The synthesized mesoporous materials were used as bilirubin adsorbents and showed higher bilirubin adsorption capacities than the commercial active carbon. The adsorption capacities of amine functionalized samples AMS and AS were larger than those of pure siliceous SBA-15 and MS, indicating that electrostatic interaction was the dominant driving force for bilirubin adsorption on mesoporous materials. Increasing the ionic strength of bilirubin solution by adding NaCl would decrease the bilirubin adsorption capacity of mesoporous material, which further demonstrated that the electrostatic interaction was the dominant driving force for bilirubin adsorption. In addition, the hydrophobic interaction provided by methyl groups could promote the bilirubin adsorption.

Tang, Tao; Zhao, Yanling; Xu, Yao; Wu, Dong; Xu, Jun; Deng, Feng

2011-05-01

189

Vertically Aligned Nanostructured Arrays of Inorganic Materials: Synthesis, Distinctive Physical Phenomena, and Device Integration  

NASA Astrophysics Data System (ADS)

The manifestation of novel physical phenomena upon scaling materials to finite size has inspired new device concepts that take advantage of the distinctive electrical, mechanical, and optical, properties of nanostructures. The development of fabrication approaches for the preparation of their 1D nanostructured form, such as nanowires and nanotubes, has contributed greatly to advancing fundamental understanding of these systems, and has spurred the integration of these materials in novel electronics, photonic devices, power sources, and energy scavenging constructs. Significant progress has been achieved over the last decade in the preparation of ordered arrays of carbon nanotubes, II---VI and III---V semiconductors, and some binary oxides such as ZnO. In contrast, relatively less attention has been focused on layered materials with potential for electrochemical energy storage. Here, we describe the catalyzed vapor transport growth of vertical arrays of orthorhombic V2O 5 nanowires. In addition, near-edge X-ray absorption fine structure (NEXAFS) spectroscopy is used to precisely probe the alignment, uniformity in crystal growth direction, and electronic structure of single-crystalline V2O5 nanowire arrays prepared by a cobalt-catalyzed vapor transport process. The dipole selection rules operational for core-level electron spectroscopy enable angle-dependant NEXAFS spectroscopy to be used as a sensitive probe of the anisotropy of these systems and provides detailed insight into bond orientation and the symmetry of the frontier orbital states. The experimental spectra are matched to previous theoretical predictions and allow experimental verification of features such as the origin of the split-off conduction band responsible for the n-type conductivity of V2O5 and the strongly anisotropic nature of vanadyl-oxygen-derived (V=O) states thought to be involved in catalysis. We have also invested substantial effort in obtaining shape and size control of metal oxide materials to obtain a fundamental understanding of the influence of finite size and surface restructuring on electronic instabilities in the proximity of the Fermi level. We present here a novel synthetic approach that takes advantage of the intrinsic octahedral symmetry of rock-salt-structured VO to facilitate the growth of six-armed nanocrystallites of related, technologically more important binary vanadium oxide V2O5 . The prepared nanostructures exhibit clear six-fold symmetry and most notably show remarkable retention of electronic structure. The latter has been evidenced through extensive X-ray absorption spectroscopy measurements. We have further designed a facile, generalizable, and entirely scalable approach for the fabrication of vertically aligned arrays of Fe2O 3/polypyrrole core---shell nanostructures and polypyrrole nanotubes. Our "all electrochemical" approach is based on the fabrication of ?-Fe 2O3 nanowire arrays by the simple heat treatment of commodity low carbon steel substrates, followed by electropolymerization of conformal polypyrrole sheaths around the nanowires. Subsequently, electrochemical etching of the nanowires yields large-area vertically aligned polypyrrole nanotube arrays on the steel substrate. The developed methodology is generalizable to functionalized pyrrole monomers and represents a significant practical advance of relevance to the technological implementation of conjugated polymer nanostructures in electrochromics, electrochemical energy storage, and sensing. As another variation of this general synthetic route, we have extended the practice of our simple oxidative process for the fabrication of large-area ZnO nanostructures, specifically highly aligned nanowire arrays integrated onto galvanized steel substrates which via a simple device design and additive piezoelectric nanopower generation were measured across the array substrates. The nanomaterial syntheses and device fabrication approaches developed here will enable facile integration of piezoelectric nanogenerators on to structural components.

Velazquez, Jesus Manuel

190

Towards rational design of peptides for selective interaction with inorganic materials  

E-print Network

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 ...

Krauland, Eric Mark

2007-01-01

191

Dental implants from functionally graded materials.  

PubMed

Functionally graded material (FGM) is a heterogeneous composite material including a number of constituents that exhibit a compositional gradient from one surface of the material to the other subsequently, resulting in a material with continuously varying properties in the thickness direction. FGMs are gaining attention for biomedical applications, especially for implants, owing to their reported superior composition. Dental implants can be functionally graded to create an optimized mechanical behavior and achieve the intended biocompatibility and osseointegration improvement. This review presents a comprehensive summary of biomaterials and manufacturing techniques researchers employ throughout the world. Generally, FGM and FGM porous biomaterials are more difficult to fabricate than uniform or homogenous biomaterials. Therefore, our discussion is intended to give the readers about successful and obstacles fabrication of FGM and porous FGM in dental implants that will bring state-of-the-art technology to the bedside and develop quality of life and present standards of care. PMID:23754641

Mehrali, Mehdi; Shirazi, Farid Seyed; Mehrali, Mohammad; Metselaar, Hendrik Simon Cornelis; Kadri, Nahrizul Adib Bin; Osman, Noor Azuan Abu

2013-10-01

192

Fracture Analysis of Functionally Graded Materials  

SciTech Connect

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.

Zhang, Ch. [Department of Civil Engineering, University of Siegen, D-57068 Siegen (Germany); Gao, X. W. [School of Aeronautics and Astronautics, Dalian University of Technology, Dalian, 116024 (China); Sladek, J.; Sladek, V. [Institute of Construction and Architecture, Slovak Academy of Sciences, 84503 Bratislava (Slovakia)

2010-05-21

193

Structure and dynamics of interfaces in organic and inorganic materials using atomic level simulation  

NASA Astrophysics Data System (ADS)

Interfaces in materials play a key role for industrial applications. The structures and dynamics at various interfaces including ferroelectric domain walls, gas-organic interface, organic-semiconductor interface and metal-gas interface are investigated with different atomic levels of simulation approaches. Ferroelectricity: Due to their unique ferroelectric and nonlinear optical properties, trigonal ferroelectrics such as LiNbO3 and LiTaO 3, are of wide interest for their potential applications in optoelectronics and nonlinear optics. The properties of these materials are heavily influenced by the shape of ferroelectric domains and domain walls. Therefore, investigation of the local structure and energetics of the ferroelectric domain walls and their interaction with defects on atomic scales, which is not clearly understood, is extremely important. The structure and energetics of ferroelectric domain walls in LiNbO 3 are examined using density functional theory (DFT) and molecular dynamics (MD) methods. The energetically favorable structures of 180° domain walls and the activation energy for domain wall motion are determined by atomic level simulations. The variation of polarization due to the presence of domain walls is also discussed. Defects can be pinned by domain walls. Various defects-domain walls interactions and the effects on domain wall motion are described using atomic level simulation methods. Although the structure of LiTaO3 is very similar with LiNbO3, it has been said experimentally that the shapes of domain walls are different with the presence of particular defects. Using both DFT and a newly developed interatomic potential for LiTaO 3, the differences in domain wall structure are understood in terms of the difference in energetics of domain walls between two materials. Polymerization: Surface polymerization by ion-assisted deposition (SPIAD) enables the control of thin film chemistry and morphology on the nanoscale during growth of conductive polymer thin films. This method allows fine tuning of optical band gaps and other optoelectronic properties of a polymer film by controlling the structure and kinetic energy of the depositing ions and neutrals. Thus, a comprehensive understanding of various mechanisms on the atomic level will contribute to optimizing growth conditions during SPIAD. SPIAD simulations are performed to study polymerization and crosslinking behavior of polythiophene molecules at the gas-organic interfaces using DFT-MD method. The growth processes for polythiophene molecules are studied by depositing thiophene molecules with 25 eV kinetic energy on terthiophene surface. The mechanism and various processes for polymerization and crosslinking of polythiophenes will be discussed. The changes in bond chemistry at the polythiophene molecules and at a PbS nanocrystalline quantum dot (organic-semiconductor interface) after a collision of C2H+ molecules with the substrate are also addressed. Surface diffusion: Surface diffusion is a key concept for understanding catalytic behavior at the surface. We develop a new code implementing adaptive kinetic Monte Carlo (AKMC) method with the dimer transition searching mechanism. The code is developed with a simple Lennard-Jones (LJ) potential. A test of dimer method is performed by using 2-dimensional testing potential. Results of surface diffusion processes of an Al adatom on Al (111) surface using AKMC method are presented.

Lee, Donghwa

194

Regulation of responsiveness of phosphorescence toward dissolved oxygen concentration by modulating polymer contents in organic-inorganic hybrid materials.  

PubMed

Platinum(II) octaethylporphyrin (PtOEP)-loaded organic-inorganic hybrids were obtained via the microwave-assisted sol-gel condensation with methyltrimethoxysilane and poly(vinylpyrrolidone). From transparent and homogeneous hybrid films, the strong phosphorescence from PtOEP was observed. Next, the resulting hybrids were immersed in the aqueous buffer, and the emission intensity was monitored by changing the dissolved oxygen level in the buffer. When the hybrid with relatively-higher amount of the silica element, the strong phosphorescence was observed even under the aerobic conditions. In contrast, the emission from the hybrids with lower amounts of the silica element was quenched under the hypoxic conditions. This is, to the best of our knowledge, the first example to demonstrate that the responsiveness of the phosphorescence intensity of PtOEP in hybrid films to the dissolved oxygen concentration in water can be modulated by changing the percentage of the contents in the material. PMID:24794749

Okada, Hiroshi; Tanaka, Kazuo; Chujo, Yoshiki

2014-06-15

195

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

NASA Astrophysics Data System (ADS)

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 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.

Huang, Jing; Fu, Xiangkai; Wang, Gang; Miao, Qiang

2011-09-01

196

Photochromic hybrid organic-inorganic liquid-crystalline materials built from nonionic surfactants and polyoxometalates: elaboration and structural study.  

PubMed

This work reports the elaboration and structural study of new hybrid organic-inorganic materials constructed via the coupling of liquid-crystalline nonionic surfactants and polyoxometalates (POMs). X-ray scattering and polarized light microscopy demonstrate that these hybrid materials, highly loaded with POMs (up to 18 wt %), are nanocomposites of liquid-crystalline lamellar structure (Lalpha), with viscoelastic properties close to those of gels. The interpretation of X-ray scattering data strongly suggests that the POMs are located close to the terminal -OH groups of the nonionic surfactants, within the aqueous sublayers. Moreover, these materials exhibit a reversible photochromism associated to the photoreduction of the polyanion. The photoinduced mixed-valence behavior has been characterized through ESR and UV-visible-near-IR spectroscopies that demonstrate the presence of W(V) metal cations and of the characteristic intervalence charge transfer band in the near-IR region, respectively. These hybrid nanocomposites exhibit optical properties that may be useful for applications involving UV-light-sensitive coatings or liquid-crystal-based photochromic switches. From a more fundamental point of view, these hybrid materials should be very helpful models for the study of both the static and dynamic properties of nano-objects confined within soft lamellar structures. PMID:18479154

Poulos, Andreas S; Constantin, Doru; Davidson, Patrick; Impéror, Marianne; Pansu, Brigitte; Panine, Pierre; Nicole, Lionel; Sanchez, Clément

2008-06-17

197

Inorganic contents of peats  

SciTech Connect

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.

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

1988-02-01

198

Effective Properties of Plates Made from Functionally Graded Materials  

E-print Network

Effective Properties of Plates Made from Functionally Graded Materials HOLM ALTENBACH, VICTOR A to plates composed of functionally graded mate- rials (FGM). Keywords: functionally graded materials made of homogeneous isotropic materials. This theory yields very simple results in applications based

Paris-Sud XI, Université de

199

Surface properties of poly(dimethylsiloxane)-based inorganic\\/organic hybrid materials  

Microsoft Academic Search

Poly(dimethylsiloxane) (PDMS)-based hybrid materials were prepared by the sol–gel method on Si wafers, Al and polystyrene (PS) substrates. The reaction was monitored by attenuated total reflectance-infrared (ATR-IR) spectroscopy. The hybrid materials have always one surface made in contact with air and one with a substrate. These surfaces were investigated by using tapping mode atomic force microscopy (AFM), X-ray photo-electron spectroscopy

Zhili Li; Wei Han; Dimitry Kozodaev; José C. M. Brokken-Zijp; Peter C. Thüne

2006-01-01

200

All-inorganic nanocrystals as a glue for BiSbTe grains: design of interfaces in mesostructured thermoelectric materials.  

PubMed

Nano- and mesostructuring is widely used in thermoelectric (TE) materials. It introduces numerous interfaces and grain boundaries that scatter phonons and decrease thermal conductivity. A new approach has been developed for the rational design of the interfaces in TE materials by using all-inorganic nanocrystals (NCs) that serve as a "glue" for mesoscopic grains. For example, circa 10?nm Bi?NCs capped with (N2H5)4Sb2Te7 chalcogenidometallate ligands can be used as an additive to BiSbTe particles. During heat treatment, NCs fill up the voids between particles and act as a "glue", joining grains in hot-pressed pellets or solution-processed films. The chemical design of NC glue allowed the selective enhancement or decrease of the majority-carrier concentration near the grain boundaries, and thus resulted in doped or de-doped interfaces in granular TE material. Chemically engineered interfaces can be used as to optimize power factor and thermal conductivity. PMID:24852900

Son, Jae Sung; Zhang, Hao; Jang, Jaeyoung; Poudel, Bed; Waring, Al; Nally, Luke; Talapin, Dmitri V

2014-07-14

201

Inorganic salts of biguanide Searching for new materials for second harmonic generation  

NASA Astrophysics Data System (ADS)

Five inorganic salts of biguanide with carbonic, nitric, phosphoric and phosphorous acids were prepared and X-ray structural analysis has been performed for three novel compounds. Biguanidium(1+) phosphite trihydrate crystallizes in the triclinic space group P1¯, a = 7.1470(1) Å, b = 9.6530(2) Å, c = 11.3140(2) Å, ? = 70.094(1)°, ? = 75.688(1)°, ? = 86.099(1)°, V = 713.71(2) Å 3, Z = 2, R = 0.0350 for 3031 observed reflections. The crystal structure is based on a network of phosphite anions and water molecules. Biguanidium(1+) cations form pairs through two intermolecular hydrogen bonds of the N-H…N type and fill the network with anions and water molecules. Biguanidium(2+) phosphite monohydrate crystallizes in the triclinic space group P1¯, a = 6.9690(2) Å, b = 7.3500(3) Å, c = 8.1730(3) Å, ? = 82.518(2)°, ? = 83.015(2)°, ? = 82.811(2)°, V = 409.44(3) Å 3, Z = 2, R = 0.0308 for 1779 observed reflections. The structure is formed of a network of alternating biguanidium(2+) cations, phosphite anions and pairs of water molecules interconnected by a system of intermolecular hydrogen bonds. Biguanidium(2+) hydrogen phosphate monohydrate crystallizes in the triclinic space group P1¯, a = 7.0630(2) Å, b = 7.8740(3) Å, c = 8.1120(3) Å, ? = 102.706(2)°, ? = 104.976(2)°, ? = 92.632(3)°, V = 422.61(3) Å 3, Z = 2, R = 0.0337 for 1827 observed reflections. The crystal structure is formed by pairs of anions that are mutually connected in chains through two water molecules. These chains are interconnected by biguanidium(2+) cations to form a three-dimensional network. The FTIR and FT Raman spectra of all five compounds were recorded, calculated (HF, B3LYP and MP2 methods) and discussed. Quantitative measurements of second harmonic generation of powdered biguanidium(2+) nitrate and novel biguanidium(2+) carbonate monohydrate at 800 nm were performed and a relative efficiency (compared to KDP) of 87% and 20% was observed, respectively.

Matulková, Irena; N?mec, Ivan; Císa?ová, Ivana; N?mec, Petr; Mi?ka, Zden?k

2008-08-01

202

Modeling Bamboo as a Functionally Graded Material  

SciTech Connect

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.

Silva, Emilio Carlos Nelli [Department of Mechatronics and Mechanical Systems, Escola Politecnica da Universidade de Sao Paulo, Av. Professor Mello Moraes, 2231, Sao Paulo, SP, 05508-900 (Brazil); Walters, Matthew C.; Paulino, Glaucio H. [Department of Civil and Environmental Engineering, University of Illinois at Urbana-Champaign, 205 North Mathews Avenue, Urbana, IL 61801 (United States)

2008-02-15

203

Alkylene-bridged polygerm- and polygermsilsesqui-oxanes: New hybrid organic-inorganic materials  

SciTech Connect

Alkylene-bridge polygerm- and polygermsilsequioxanes have been formed by hydrolysis-condensation of their corresponding (EtO){sub 3}M(CH{sub 2}){sub n}Ge(OEt){sub 3} monomers under HCl- and NEt{sub 3}-catalyzed conditions in ethanol. Solid state {sup 13}C and {sup 29}Si NMR indicate the retention of the alkylene bridging moiety during polymerization. The resulting aerogels are mesoporous materials with high surface areas. Incorporation of the short ethylene bridging unit results in higher surface areas than when heylene bridges are present. The porous nature of hexylene-bridged hybrid network [Si(CH{sub 2}){sub 6}GeO{sub 3}]{sub n} appears insensitive to the acidic or basic nature of the catalyst employed in it formation, in contrast to its polysilsesquioxane counterpart. Work is underway to determine the origin of porosity in these materials, and to characterize xerogel materials generated from these monomers.

Jamison, G.M.; Loy, D.A.; Zender, G. [Sandia National Labs., Albuquerque, NM (United States); Shea, K.J. [California Univ., Irvine, CA (United States). Dept. of Chemistry

1993-12-31

204

Functional polymers: materials for smart structures  

NASA Astrophysics Data System (ADS)

The preparation and properties of four classes of functional polymeric materials capable of responding to changes in the environment are reported. The microphase separated mixed (ionic and electronic) or MIEC diblock copolymers are composed of an electronic conductive and an ionic conductive block, and are nanostructured smart materials for application in MEMS devices. Processable copolymers of 3-alkyl or 3-phenylthiophene and (3- oligodimethylsiloxane)thiophene have been prepared as electrorheological fluids. Also a facile methodology for preparing highly ionic conductive and elastomeric solid electrolytes is reported. Finally, molecular composites of poly(2-vinylpyridine) and lithium perchlorate have been prepared. These composites have dielectric constants as high as 16 at 12 GHz.

Arnold, Shannon C.; Pratt, Lawrence M.; Khan, Saeed M.; Li, Jean; Khan, Ishrat M.

1995-05-01

205

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

NASA Astrophysics Data System (ADS)

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

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

206

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

NASA Technical Reports Server (NTRS)

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.

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

207

Structure and dynamics of interfaces in organic and inorganic materials using atomic level simulation  

Microsoft Academic Search

Interfaces in materials play a key role for industrial applications. The structures and dynamics at various interfaces including ferroelectric domain walls, gas-organic interface, organic-semiconductor interface and metal-gas interface are investigated with different atomic levels of simulation approaches. Ferroelectricity: Due to their unique ferroelectric and nonlinear optical properties, trigonal ferroelectrics such as LiNbO3 and LiTaO 3, are of wide interest for

Donghwa Lee

2010-01-01

208

Porous Silica Obtained from Biodegradable and Biocompatible Inorganic-Organic Hybrid Materials  

Microsoft Academic Search

Porous silicas have been successfully prepared from poly(e-caprolactone) (PCL)-silica hybrid materials based on the template approach. The final texture of the porous silica can be tailored by the PCL template, i.e., molecular weight and molecular weight distribution, content, type and number of reactive end-groups per chain. Porosity has been investigated by nitrogen adsorption-desorption technique and small angle X-ray scattering (SAXS).

D. Tian; S. Blacher; Ph. Dubois; J. P. Pirard; R. Jérôme

1998-01-01

209

Inorganic-organic Hybrid Materials Based on Nano-polyoxometalates and Surfactants  

Microsoft Academic Search

\\u000a A series of nano-scale polyoxometalates (POMs) with beautiful topologies have been successfully synthesized by destroying\\u000a the hydration shell of metal oxides. Their magnetic, electronic, and photoluminescent properties and valuable applications\\u000a in catalysis, medicine, and material science are discussed. By interaction with oppositely charged surfactants, an interesting\\u000a phase transfer of POMs occurs from aqueous solution to chloroform solution by forming hydrophobic

Peiqin Tang; Jingcheng Hao

210

On a Simple Nonisothermal Adsorption Experiment with Organic Vapors and an Inertial Microbalance To Study the Surface Properties of Hybrid (Organic/Inorganic) Porous Materials.  

PubMed

A nonisothermal adsorption experiment using a controlled flow of cyclopentane in the 333-313 K range is used to simultaneously estimate the specific surface area and micropore volume of a hybrid (organic/inorganic) alcogel. For reference, the method is also applied to an all-inorganic material with a more rigid structure, namely, a high surface area SiO(2)-Al(2)O(3). The proposed data analysis provides guidelines to determine whether adsorption data on a certain adsorbate/adsorbent system can be modeled effectively as a convolution of BET (meso- and macropore) and Dubinin-Radushkevitch (DR, micropore) contributions. Copyright 2000 Academic Press. PMID:10708512

Larsen; Silva; de Silva RV

2000-04-01

211

Novel inorganic\\/organic hybrid materials based on blown soybean oil with sol–gel precursors  

Microsoft Academic Search

New ceramer coatings based on blown soybean oil with sol–gel precursors were prepared and evaluated as a function of the blowing process and sol–gel precursors content. Soybean oils were blown at three different rates in order to optimize the blowing process. Three sol–gel precursors, titanium (IV) i-propoxide, titanium (IV) di-i-propoxide bis-acetoacetonate, and zirconium n-propoxide were then used with the blown

Ganghua Teng; Joseph R Wegner; Greta J Hurtt; Mark D Soucek

2001-01-01

212

One-step synthesis of organic-inorganic hybrid asymmetric dimer particles via miniemulsion polymerization and functionalization with silver.  

PubMed

Organic-inorganic polystyrene (PSt)-silica (SiO2) hybrid asymmetric particles were prepared in one step by a miniemulsion polymerization technique. The organic and inorganic reagents were confined in miniemulsion microreactor droplets. After the formation of PSt and SiO2, internal phase separation inside the droplets was accelerated owing to the hydrophobicity of PSt and the hydrophilicity of SiO2. Therefore, PSt-SiO2 hybrid asymmetric particles could be synthesized in one step. Between each pair of asymmetric particles, silane couplers act as bridges connecting the PSt and SiO2 particles. The size of PSt particles in these asymmetric particles was easily tuned either by changing the weight ratio of St/TEOS or by varying the sonication power during the miniemulsion preparation. After functionalization of the as-prepared asymmetric dimers by surface decoration with Ag particles, enhanced surface-enhanced Raman scattering (SERS) properties were observed due to electromagnetic enhancement of the added Ag colloids. PMID:18805542

Lu, Wei; Chen, Min; Wu, Limin

2008-12-01

213

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

Microsoft Academic Search

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 (31P, 1H, 13C).

Ketan Patel; Anjali Patel

214

Solvothermal synthesis and characterization of two inorganic-organic hybrid materials based on barium.  

PubMed

Two metal-organic frameworks containing barium were synthesized hydrothermally and investigated for their catalytic properties. Ba(2)F(2)[O(3)SC(2)H(4)SO(3)] has barium fluoride layers linked by organic 1,2-ethanedisulfonate molecules. Ba[O(3)SC(2)H(4)SO(3)] has discrete barium centers arranged in layers and connected covalently by ethanedisulfonate bridges. Thermogravimetric analysis showed that Ba(2)F(2)[O(3)SC(2)H(4)SO(3)] is stable to ca. 325 °C and Ba[O(3)SC(2)H(4)SO(3)] to ca. 375 °C. These materials expand the metal-organic frameworks available for group II metals bound to organodisulfonate linkers and are potentially useful for a range of heterogeneous acid catalysis reactions. PMID:22968326

Abdollahian, Yashar; Hauser, Jesse L; Rogow, David L; Oliver, Allen G; Oliver, Scott R J

2012-10-28

215

Gigantic swelling of inorganic layered materials: a bridge to molecularly thin two-dimensional nanosheets.  

PubMed

Platy microcrystals of a typical layered material, protonated titanate, have been shown to undergo an enormous degree of swelling in aqueous solutions of various amines, including tertiary amines, quaternary ammonium hydroxides, and primary amines. Introducing these solutions expanded the crystal gallery height by up to ~100-fold. Through systematic analysis, we determined that ammonium ion intercalation is predominantly affected by the acid-base equilibrium and that the degree of swelling or inflow of H2O is controlled by the osmotic pressure balance between the gallery and the solution environment, both of which are relatively independent of electrolyte identity but substantially dependent on molarity. In solutions of tertiary amines and quaternary ammonium hydroxides, the uptake of ammonium ions increases nearly linearly with increasing external concentration before reaching a saturation plateau, i.e., ~40% relative to the cation-exchange capacity of the crystals used. The only exception is tetrabutylammonium ions, which yield a lower saturation value, ~30%, owing to steric effects. The swelling behaviors in some primary amine solutions differ as a result of the effect of attractive forces between amine solute molecules on the solution osmotic pressure. Although the swelling is essentially colligative in nature, the stability of the resultant swollen structure is heavily dependent on the chemical nature of the guest ions. Intercalated ions of higher polarity and smaller size help stabilize the swollen structure, whereas ions of lower polarity and larger size lead readily to exfoliation. The insight gained from this study sheds new light on both the incorporation of guest molecules into a gallery of layered structures in general and the exfoliation of materials into elementary single-layer nanosheets. PMID:24635385

Geng, Fengxia; Ma, Renzhi; Ebina, Yasuo; Yamauchi, Yusuke; Miyamoto, Nobuyoshi; Sasaki, Takayoshi

2014-04-01

216

Catechol-based biomimetic functional materials.  

PubMed

Catechols are found in nature taking part in a remarkably broad scope of biochemical processes and functions. Though not exclusively, such versatility may be traced back to several properties uniquely found together in the o-dihydroxyaryl chemical function; namely, its ability to establish reversible equilibria at moderate redox potentials and pHs and to irreversibly cross-link through complex oxidation mechanisms; its excellent chelating properties, greatly exemplified by, but by no means exclusive, to the binding of Fe(3+); and the diverse modes of interaction of the vicinal hydroxyl groups with all kinds of surfaces of remarkably different chemical and physical nature. Thanks to this diversity, catechols can be found either as simple molecular systems, forming part of supramolacular structures, coordinated to different metal ions or as macromolecules mostly arising from polymerization mechanisms through covalent bonds. Such versatility has allowed catechols to participate in several natural processes and functions that range from the adhesive properties of marine organisms to the storage of some transition metal ions. As a result of such an astonishing range of functionalities, catechol-based systems have in recent years been subject to intense research, aimed at mimicking these natural systems in order to develop new functional materials and coatings. A comprehensive review of these studies is discussed in this paper. PMID:23180685

Sedó, Josep; Saiz-Poseu, Javier; Busqué, Felix; Ruiz-Molina, Daniel

2013-02-01

217

Magnetic spectroscopy and microscopy of functional materials  

SciTech Connect

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).

Jenkins, C.A.

2011-01-28

218

Formation of helix-containing rods in a hybrid inorganic-organic material  

NASA Astrophysics Data System (ADS)

The novel aluminum ethylenediphosphonate fluoride, [HN(CH 2CH 2NH 3) 3][Al 2(O 3PCH 2CH 2PO 3) 2F 2]·H 2O ( 1) (monoclinic, P2 1/n, a=12.145(4) Å, b=9.265(3) Å, c=20.422(6) Å, ?=104.952(4)°, Z=3, R1=0.092, wR2=0.196) has been synthesized by solvothermal methods in the presence of tris(2-aminoethyl)amine and its structure determined using single microcrystal X-ray diffraction data. Compound 1 is a one-dimensional extended chain structure composed of well-separated anionic [Al 2(O 3PCH 2CH 2PO 3) 2F 2] 4- rods containing helical chains of corner-shared cis-AlO 4F 2 octahedra at their core. The charge-compensating tris(2-aminoethyl)ammonium cations separate the anionic [Al 2(O 3PCH 2CH 2PO 3) 2F 2] 4- rods that contain either left- or right-handed helical chains. The incorporation of the organic components into this hybrid material has aided the adoption of one-dimensionality by the compound and defined the pitch of the helical AlO 4F chain.

Yuan, Zhanhui; Clegg, William; Attfield, Martin P.

2009-11-01

219

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

NASA Technical Reports Server (NTRS)

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.

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

1979-01-01

220

Long-term self-assembly of inorganic layered materials influenced by the local states of the interlayer cations.  

PubMed

A wide variety of parameters as, e.g., temperature, humidity, particle size, and cation state are known to influence the agglomeration process of two-dimensional (2D) nanosheets, called self-assembly, in inorganic layered materials. The detailed studies on which parameters are decisive and how they influence the self-assembly, however, have not been performed yet. Here, the long-term self-assembly was studied for layered stevensite and hectorite, and compared with our previous data of saponite for elucidating an influence of local states of the interlayer cations. The results were analyzed with respect to a recently established rheological model, in which 2D nanosheets migrate parallel to the layer direction aided by water molecules as lubricants [K. Sato et al., J. Phys. Chem. C, 2012, 116, 22954]. With decreasing the strength of the local electric fields facing to the interlayer spaces, cation positions split into two or three, which makes the distribution of water molecules more uniformly. These water molecules enhance the rheological motion of the 2D nanosheets parallel to the layer direction, thus accelerating the self-assembly process. PMID:24770790

Sato, Kiminori; Numata, Kazuomi; Dai, Weili; Hunger, Michael

2014-06-14

221

Photothermal characterization of functionally graded materials (FGM)  

NASA Astrophysics Data System (ADS)

This paper deals with the photothermal characterization of functionally graded materials (FGM) whose thermal properties are varying parallel to the sample surface. Simple experimental configurations and associated inversion procedures are proposed either for thermal mapping or for pitch-catch imaging mode. The photothermally induced periodic temperature field at the sample surface is first calculated using a specific code, then the inversion procedures are checked using a simulated set of data. Preliminary experimental results are presented outlining need of specific filter to cope with experimental noise.

Jumel, J.; Terrien, N.; Arnould, O.; Krapez, J. C.; Lepoutre, F.

2002-05-01

222

Organic-inorganic hybrids : a route towards soluble magnetic electronics.  

E-print Network

??This thesis discusses the use of organic-inorganic hybrids in the development of soluble magnetic electronic materials. Organic-inorganic hybrids combine organic and inorganic materials at the… (more)

Arkenbout, Anne Helena

2010-01-01

223

Direct synthesis of a photoactive inorganic-organic mesostructured hybrid material and its application as a photocatalyst.  

PubMed

A photoactive, hexagonally structured mesoporous material (Tyl-MCM41) is produced through co-hydrolysis of SiO(2) and a trialkoxysilane-functionalized trityl cation as photoactive species. The formation of the corresponding triphenylmethanol precursor in the material is confirmed by spectroscopic techniques. The hybrid material has an ordered structure with a narrow pore size distribution typical of ordered mesoporous MCM-41-type materials. The triarylcarbinol molecules incorporated into this hybrid structure (Triphol-MCM41) generate trityl cations under acidic conditions, which are photoactive and able to promote the photosensitized dimerization of 1,3-cyclohexadiene in a heterogeneous solid-liquid system. The material is stable and can be recycled without loss of the photochemical activity. PMID:19229898

Corma, Avelino; Navarro, Maria T; Rey, Fernando; Ruiz, Violeta R; Sabater, Maria J

2009-05-11

224

Gap Wave Propagation in Functionally Graded Piezoelectric Material Structures  

E-print Network

Gap Wave Propagation in Functionally Graded Piezoelectric Material Structures Jianke Du, Kai Xian@nbu.edu.cn Abstract-Shear horizontal gap wave propagating between functionally graded piezoelectric material (FGPM-space and a piezoceramic plate were investigated in [3]. A new-style material called functionally graded material (FGM

Wang, Ji

225

Functional Hydrogel Materials Inspired by Amyloid  

NASA Astrophysics Data System (ADS)

Protein assembly resulting in the formation of amyloid fibrils, assemblies rich in cross beta-sheet structure, is normally thought of as a deleterious event associated with disease. However, amyloid formation is also involved in a diverse array of normal biological functions such as cell adhesion, melanin synthesis, insect defense mechanism and modulation of water surface tension by fungi and bacteria. These findings indicate that Nature has evolved to take advantage of large, proteinaceous fibrillar assemblies to elicit function. We are designing functional materials, namely hydrogels, from peptides that self-assembled into fibrillar networks, rich in cross beta-sheet structure. These gels can be used for the direct encapsulation and delivery of small molecule-, protein- and cell-based therapeutics. Loaded gels exhibit shear-thinning/self-healing mechanical properties enabling their delivery via syringe. In addition to their use for delivery, we have found that some of these gels display antibacterial activity. Although cytocompatible towards mammalian cells, the hydrogels can kill a broad spectrum of bacteria on contact.

Schneider, Joel

2012-02-01

226

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

E-print Network

Two-dimensional optimization of material composition of functionally graded materials using-dimensional simulation and optimization of material distribution of functionally graded materials for thermomechanical processes. The proposed approach focuses on metal/ceramic functionally graded materials, which offer great

Vel, Senthil

227

Preparation of La 2 O 3 -TiO 2 SiO 2 Inorganic-Organic Hybrid Materials and Their Optical Properties  

Microsoft Academic Search

Inorganic-organic hybrid materials in La2O3-TiO2-SiO2 system were prepared from La(NO3)3, titanium tetraisopropoxide, and silicon alkoxides. Ternary transparent materials prepared from glycidyloxypropyltrimethoxysilane (GPTS) were obtained in a wide composition region (La2O3 = 50 mol%, TiO2 = 40 mol%). Hybrid materials prepared using methyltrimethoxysilane (MTMS) at MTMS\\/TMOS = 1 were transparent in the composition of La2O3 = 30 mol% and TiO2 =

Mitsunobu Iwasaki; Ken-Ichiro Kashimura; Hitoshi Masaki; Seishiro Ito

2003-01-01

228

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

PubMed

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

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

2012-12-01

229

2D-network of inorganic-organic hybrid material built on Keggin type polyoxometallate and amino acid: [L-CHNO][(PO)MoO].5HO  

Microsoft Academic Search

A new inorganic-organic hybrid material based on polyoxometallate, [L-CHNO][(PO)MoO].5HO, has been successfully synthesized and characterized by single-crystal X-ray analysis, elemental analysis, infrared and ultraviolet spectroscopy, proton nuclear magnetic resonance and differential thermal analysis techniques. The title compound crystallizes in the monoclinic space group, P2\\/c{sub ,} with a = 12.4938 (8) A, b = 19.9326 (12) A, c = 17.9270 (11)

M. H. Alizadeh; M. Mirzaei; H. Razavi

2008-01-01

230

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

Microsoft Academic Search

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

K. Kutsuzawa; E. H. Chowdhury; M. Nagaoka; K. Maruyama; Y. Akiyama; T.. Akaike

2006-01-01

231

A review on the application of inorganic nano-structured materials in the modification of textiles: focus on anti-microbial properties.  

PubMed

Textiles can provide a suitable substrate to grow micro-organisms especially at appropriate humidity and temperature in contact to human body. Recently, increasing public concern about hygiene has been driving many investigations for anti-microbial modification of textiles. However, using many anti-microbial agents has been avoided because of their possible harmful or toxic effects. Application of inorganic nano-particles and their nano-composites would be a good alternative. This review paper has focused on the properties and applications of inorganic nano-structured materials with good anti-microbial activity potential for textile modification. The discussed nano-structured anti-microbial agents include TiO(2) nano-particles, metallic and non-metallic TiO(2) nano-composites, titania nanotubes (TNTs), silver nano-particles, silver-based nano-structured materials, gold nano-particles, zinc oxide nano-particles and nano-rods, copper nano-particles, carbon nanotubes (CNTs), nano-clay and its modified forms, gallium, liposomes loaded nano-particles, metallic and inorganic dendrimers nano-composite, nano-capsules and cyclodextrins containing nano-particles. This review is also concerned with the application methods for the modification of textiles using nano-structured materials. PMID:20417070

Dastjerdi, Roya; Montazer, Majid

2010-08-01

232

Nanoscale hybrid protein/polymer functionalized materials  

NASA Astrophysics Data System (ADS)

Block copolymer-based membrane technology represents a versatile class of nanoscale materials in which biomolecules, such as membrane proteins, can be reconstituted. Our work has demonstrated the fabrication of large-area, protein- enhanced membranes that possess significant performance improvements in protein functionality. Among its many advantages over conventional lipid-based membrane systems, block copolymers can mimic natural cell biomembrane environments in a single chain, enabling large-area membrane fabrication using methods like Langmuir-Blodgett (LB) deposition, or spontaneous protein-functionalized nano-vesicle formation. The membrane protein, Bacteriorhodopsin (BR), found in Halobacterium Halobium, is a light-actuated proton pump that develops gradients towards the demonstration of coupled functionality with other membrane proteins to effect ATP production, or production of electricity through Bacteriorhodopsin activity-dependent reversal of Cytochrome C Oxidase (COX), found in Rhodobacter Sphaeroides. Using quantum dot-labeled, engineered protein constructs, we have demonstrated large-scale insertion of proteins into block copolymer Langmuir-Blodgett (LB) films as well as measurable pH changes based upon light-actuated proton pumping. Light actuated-activity across the protein-functionalized membrane when fully enclosed in a sol-gel matrix has also been observed using impedance spectroscopy. Initial data has suggested a significant pH change of up to 1.75 in a volume of 100 mL and surface area of 0.317cm2, a level that is capable of powering a number of proton-gradient dependent proteins towards the buildup of a robust, hybrid protein/polymer device. Recent atomic force microscopy studies of the protein-embedded polymer film samples have revealed the formation of protein aggregate-based pattern generation with very uniform torus-shaped rings. Current work focused towards characterizing the effects that various pattern formations can have on the efficiency of protein functionality, as well as film stability in an effort to develop a robust polymer membrane will also be discussed.

Ho, Dean; Chu, Ben; Lee, Hyeseung; Montemagno, Carlo D.

2004-07-01

233

Inorganic separator technology program  

NASA Technical Reports Server (NTRS)

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.

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

1973-01-01

234

Sorption of pure N2O to biochars and other organic and inorganic materials under anhydrous conditions.  

PubMed

Suppression of nitrous oxide (N2O) emissions from soil is commonly observed after amendment with biochar. The mechanisms accounting for this suppression are not yet understood. One possible contributing mechanism is N2O sorption to biochar. The sorption of N2O and carbon dioxide (CO2) to four biochars was measured in an anhydrous system with pure N2O. The biochar data were compared to those for two activated carbons and other components potentially present in soils-uncharred pine wood and peat-and five inorganic metal oxides with variable surface areas. Langmuir maximum sorption capacities (Qmax) for N2O on the pine wood biochars (generated between 250 and 500 °C) and activated carbons were 17-73 cm(3) g(-1) at 20 °C (median 51 cm(3) g(-1)), with Langmuir affinities (b) of 2-5 atm(-1) (median 3.4 atm(-1)). Both Qmax and b of the charred materials were substantially higher than those for peat, uncharred wood, and metal oxides [Qmax 1-34 cm(3) g(-1) (median 7 cm(3) g(-1)); b 0.4-1.7 atm(-1) (median 0.7 atm(-1))]. This indicates that biochar can bind N2O more strongly than both mineral and organic soil materials. Qmax and b for CO2 were comparable to those for N2O. Modeled sorption coefficients obtained with an independent polyparameter-linear free-energy relationship matched measured data within a factor 2 for mineral surfaces but underestimated by a factor of 5-24 for biochar and carbonaceous surfaces. Isosteric enthalpies of sorption of N2O were mostly between -20 and -30 kJ mol(-1), slightly more exothermic than enthalpies of condensation (-16.1 kJ mol(-1)). Qmax of N2O on biochar (50000-130000 ?g g(-1) biochar at 20 °C) exceeded the N2O emission suppressions observed in the literature (range 0.5-960 ?g g(-1) biochar; median 16 ?g g(-1)) by several orders of magnitude. Thus, the hypothesis could not be falsified that sorption of N2O to biochar is a mechanism of N2O emission suppression. PMID:23758057

Cornelissen, Gerard; Rutherford, David W; Arp, Hans Peter H; Dörsch, Peter; Kelly, Charlene N; Rostad, Colleen E

2013-07-16

235

Love wave propagation in functionally graded piezoelectric material layer  

E-print Network

Love wave propagation in functionally graded piezoelectric material layer Jianke Du *, Xiaoying Jin is used to investigate Love waves in functionally graded piezoelectric material (FGPM) layer bonded functionally graded material (FGM) was proposed to solve problems in the thermal- protection systems

Wang, Ji

236

Multi-objective optimization of functionally graded materials with temperature-dependent material properties  

E-print Network

Multi-objective optimization of functionally graded materials with temperature-dependent material distribution of functionally graded materials with tem- perature-dependent material properties for steady thermomechanical processes. The proposed approach focuses on metal/ceramic and metal/metal functionally graded

Vel, Senthil

237

Research Interests: Microporous and mesoporous solids, organic-inorganic hybrids and zeolites, structural studies, adsorption and catalysis  

Microsoft Academic Search

Our research is concerned with the design and synthesis of novel porous framework solids that find applications as functional materials, in particular as adsorbents and catalysts. These include zeolites and related structures, through novel organic-inorganic hybrid solids to well-ordered mesoporous solids. We introduce design into the synthesis of these materials by using molecular templates and inorganic building blocks. Once prepared,

Paul A. Wright

238

Conducting Polymer-Inorganic Nanoparticle (CPIN) Nanoarrays for Battery Applications - Final Technical Report  

Microsoft Academic Search

Our objective was to develop new, self-assembling conducting polymer-inorganic nanoparticle nanoarrays (CPIN nanoarrays) comprised of nanoparticles of inorganic Li+ insertion compounds that are wired together with oligomeric chains of derivatives of polythiophene. Using these nanoarrays, we developed an understanding of the relationship between structure and electrochemical function for nanostructured materials. Such nanoarrays are expected to have extremely high specific energy

Buttry; Daniel A

2006-01-01

239

Intensively competitive adsorption for heavy metal ions by PAMAM-SBA-15 and EDTA-PAMAM-SBA-15 inorganic–organic hybrid materials  

Microsoft Academic Search

EDTA modified Gn-PAMAM-SBA-15 (n=1, 2, 3 and 4) inorganic–organic hybrid materials were successfully prepared with the structures characterized by XRD, FT-IR spectra and CP-MAS 13CNMR. The adsorption characters of the Gn-PAMAM-SBA-15 and EDTA modified materials were studied. The G3- and G4-PAMAM-SBA-15 samples showed high selectivities for Cr3+, Pb2+ and Zn2+ with the distribution coefficients Kd values larger than 1.25×104. When

Yijun Jiang; Qiuming Gao; Huaguang Yu; Yirui Chen; Feng Deng

2007-01-01

240

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

ERIC Educational Resources Information Center

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 +]…

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

2006-01-01

241

Structure and reaction studies of biological organic and inorganic composite materials: Abalone shells, diatoms, and a unique birch bark  

NASA Astrophysics Data System (ADS)

Biopolymer/calcium carbonate composites grown on inorganic abiotic substrates implanted between the shell and the shell-secreting epithelium of live red abalones (Haliotis rufescens) results in an unusual highly (104)-oriented aggregate of microcrystalline calcite that precedes nacre deposition. Calcite of this orientation has never before been observed in nature. Also with this method, nacre deposition is found to correct for calcite surface roughness and chemically anomalous surfaces. Pole figure X-ray diffraction studies of these "flat pearls" provide comparisons of preferred orientation of the various mineral components of the abalone shell. Complete conversion of the aragonite in abalone nacre to hydroxyapatite in hydrothermal phosphate solution results in an oriented polycrystalline aggregate with ultrastructure preservation and an unexpected preferred orientation different from that of other biominerals and abiogenic CaCO3 samples subjected to this reaction. The new orientation, which increases with reaction time, may result from the organization of the organic matrix in the nacre, which directs the hydrothermal solution through the material. This orientation suggests strongly that the conversion proceeds via a dissolution-recrystallization mechanism, rather than by topotaxy, which was previously proposed. In addition to cellulose I, a highly oriented cellulose-II-like polymer was found in the bark of Prunus serrula, an exceptionally strong, tough, and extensible composite film. The cellulose II polymorph, which has not previously been found in nature, may be accordion-folded in the plane of the bark thickness and contribute to the strength and unusual behavior with plasticization of this natural film. The silica frustule of the diatom Skeletonema costatum has a surface area of 135 mm2/g and contains 1.5--2 wt % occluded organic. This organic includes a water-insoluble scaffolding. When treated with organic oxidizers, the chitin secreted by the diatom Thalassiosira weisflogii forms a flexible paperlike composite. A mild, rapid synthesis of hydrated sodium aluminosilicate sodalite, Na 3(AlSiO4)3·4H2O, synthesis of mesoporous silica at neutral pH, and the synthesis of gem-quality opal also are presented.

Zaremba, Charlotte Marie

242

Series of inorganic-organic hybrid materials constructed from octamolybdates and metal-organic frameworks: syntheses, structures, and physical properties.  

PubMed

Series of inorganic-organic hybrid materials based on octamolybdates, silver ions, and multidentate N-donor ligands, namely, [Ag(2)(2,3'-tmbpt)(?-Mo(8)O(26))(0.5)] (1), [Ag(2)(2,4'-tmbpt)(2)(?-Mo(8)O(26))(0.5)(H(2)O)(0.5)]·2H(2)O (2), [Ag(3)(3,3'-tmbpt)(2)(?-H(2)Mo(8)O(26))(0.5)(?-Mo(8)O(26))(0.5)]·3.5H(2)O (3), [Ag(2)(3,3'-tmbpt)(?-Mo(8)O(26))(0.5)]·1.75H(2)O (4), [Ag(2)(3,4'-tmbpt)(2)(?-Mo(8)O(26))(0.5)]·0.5H(2)O (5), and [Ag(3,4'-Htmbpt)(?-Mo(8)O(26))(0.5)] (6), where 2,3'-tmbpt = 1-((1H-1,2,4-triazol-1-yl)methyl)-3-(3-pyridyl)-5-(2-pyridyl)-1,2,4-triazole), 2,4'-tmbpt = 1-((1H-1,2,4-triazol-1-yl)methyl)-3-(4-pyridyl)-5-(2-pyridyl)-1,2,4-triazole), 3,3'-tmbpt = 1-((1H-1,2,4-triazol-1-yl)methyl)-3,5-bis(3-pyridyl)-1,2,4-triazole, and 3,4'-tmbpt = 1-((1H-1,2,4-triazol-1-yl)methyl)-3-(4-pyridyl)-5-(3-pyridyl)-1,2,4-triazole) have been synthesized under hydrothermal conditions. Compound 1 displays a rare 3D (3,4,8)-connected net with (4·8(2))(4(2)·8(4))(4(3)·8(20)·10(5)) topology. Compound 2 shows a rare 3D (4,6)-connected self-catenated framework with (6(4)·8(2))(4(2)·6(3)·8(2))(4(2)·6(8)·8(4)·10) topology. Compound 3 is a scarce 3D framework based on two different kinds of [Mo(8)O(26)](4-) isomers. Compound 4 exhibits a 3D framework constructed by silver-organic sheets and the rare [?-Mo(8)O(26)](4-) anions. Compound 5 shows an interesting 1D ? 2D polythreaded structure. Compound 6 displays a 2D layer structure, which is further linked by the N-H···O hydrogen bonds to form a 3D supramolecular architecture. Their structures have been further characterized by infrared spectra (IR), elemental analyses, powder X-ray diffraction (PXRD), electrochemistry and photoluminesce. Moreover, the photocatalytic activities for degradation of organic pollutant have been investigated for compounds 3-6. PMID:23088791

Kan, Wei-Qiu; Yang, Jin; Liu, Ying-Ying; Ma, Jian-Fang

2012-11-01

243

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

SciTech Connect

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.

Patel, Ketan [Chemistry Department, Faculty of Science, M.S. University of Baroda, Vadodara 390 002 (India)] [Chemistry Department, Faculty of Science, M.S. University of Baroda, Vadodara 390 002 (India); Patel, Anjali, E-mail: aupatel_chem@yahoo.com [Chemistry Department, Faculty of Science, M.S. University of Baroda, Vadodara 390 002 (India)] [Chemistry Department, Faculty of Science, M.S. University of Baroda, Vadodara 390 002 (India)

2012-02-15

244

Inorganic nanoparticles for multimodal molecular imaging.  

PubMed

Multimodal molecular imaging can offer a synergistic improvement of diagnostic ability over a single imaging modality. Recent development of hybrid imaging systems has profoundly impacted the pool of available multimodal imaging probes. In particular, much interest has been focused on biocompatible, inorganic nanoparticle-based multimodal probes. Inorganic nanoparticles offer exceptional advantages to the field of multimodal imaging owing to their unique characteristics, such as nanometer dimensions, tunable imaging properties, and multifunctionality. Nanoparticles mainly based on iron oxide, quantum dots, gold, and silica have been applied to various imaging modalities to characterize and image specific biologic processes on a molecular level. A combination of nanoparticles and other materials such as biomolecules, polymers, and radiometals continue to increase functionality for in vivo multimodal imaging and therapeutic agents. In this review, we discuss the unique concepts, characteristics, and applications of the various multimodal imaging probes based on inorganic nanoparticles. PMID:21303611

Swierczewska, Magdalena; Lee, Seulki; Chen, Xiaoyuan

2011-02-01

245

Inorganic Nanoparticles for Multimodal Molecular Imaging  

PubMed Central

Multimodal molecular imaging can offer a synergistic improvement of diagnostic ability over a single imaging modality. Recent development of hybrid imaging systems has profoundly impacted the pool of available multimodal imaging probes. In particular, much interest has been focused on biocompatible, inorganic nanoparticle–based multimodal probes. Inorganic nanoparticles offer exceptional advantages to the field of multimodal imaging owing to their unique characteristics, such as nanometer dimensions, tunable imaging properties, and multifunctionality. Nanoparticles mainly based on iron oxide, quantum dots, gold, and silica have been applied to various imaging modalities to characterize and image specific biologic processes on a molecular level. A combination of nanoparticles and other materials such as biomolecules, polymers, and radiometals continue to increase functionality for in vivo multimodal imaging and therapeutic agents. In this review, we discuss the unique concepts, characteristics, and applications of the various multimodal imaging probes based on inorganic nanoparticles. PMID:21303611

Swierczewska, Magdalena; Lee, Seulki; Chen, Xiaoyuan

2013-01-01

246

One-step synthesis of organic–inorganic hybrid asymmetric dimer particles via miniemulsion polymerization and functionalization with silver  

Microsoft Academic Search

Organic–inorganic polystyrene (PSt)–silica (SiO2) hybrid asymmetric particles were prepared in one step by a miniemulsion polymerization technique. The organic and inorganic reagents were confined in miniemulsion microreactor droplets. After the formation of PSt and SiO2, internal phase separation inside the droplets was accelerated owing to the hydrophobicity of PSt and the hydrophilicity of SiO2. Therefore, PSt–SiO2 hybrid asymmetric particles could

Wei Lu; Min Chen; Limin Wu

2008-01-01

247

Biomineralized structural materials with functional optical properties  

E-print Network

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 ...

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

2014-01-01

248

Numerical interconversion between linear viscoelastic material functions with regularization  

Microsoft Academic Search

In this paper, interconversion between linear viscoelastic material functions is stud- ied emphasizing materials with relatively fast rate of relaxation. The aim of this paper is to study the whole material function determination process from a linear viscoelastic experiment to interconversion by taking into account non-ideal loading and noisiness of the data in such an experiment. No assumptions are made

Joonas Sorvari; Matti Malinen

2006-01-01

249

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

SciTech Connect

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)

Luca, V. [Programa Nacional de Gestion de Residuos Radiactivos, Comision Nacional de Energia Atomica, Centro Atomico Constituyentes, Av. General, Paz 1499, 1650 San Martin, Provincia de Buenos Aires (Argentina)

2013-07-01

250

Density functional theory in materials science  

PubMed Central

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

Neugebauer, Jorg; Hickel, Tilmann

2013-01-01

251

Stochastic multiscale models for fracture analysis of functionally graded materials  

E-print Network

Stochastic multiscale models for fracture analysis of functionally graded materials Arindam A functionally graded material (FGM) is an engineered composite medium in which the composition of constituent of a crack in a two-phase, functionally graded composite. The models involve stochastic description

Rahman, Sharif

252

Indirectly detected through-bond chemical shift correlation NMR spectroscopy in solids under fast MAS: Studies of organic-inorganic hybrid materials  

SciTech Connect

Indirectly detected, through-bond NMR correlation spectra between {sup 13}C and {sup 1}H nuclei are reported for the first time in solid state. The capabilities of the new method are demonstrated using naturally abundant organic-inorganic mesoporous hybrid materials. The time performance is significantly better, almost by a factor of 10, than in the corresponding {sup 13}C detected experiment. The proposed scheme represents a new analytical tool for studying other solid-state systems and the basis for the development of more advanced 2D and 3D correlation methods.

Mao, Kanmi; Wiench, Jerzy; Lin, Victor S.-Y.; Pruski, Marek

2008-10-12

253

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

E-print Network

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 ...

Kwan, Phoebe Hoi-Ying, 1978-

2005-01-01

254

M13 Bacteriophage Displaying DOPA on Surfaces: Fabrication of Various Nanostructured Inorganic Materials without Time-Consuming Screening Processes.  

PubMed

M13 bacteriophage (phage) was engineered for the use as a versatile template for preparing various nanostructured materials via genetic engineering coupled to enzymatic chemical conversions. First, we engineered the M13 phage to display TyrGluGluGlu (YEEE) on the pVIII coat protein and then enzymatically converted the Tyr residue to 3,4-dihydroxyl-l-phenylalanine (DOPA). The DOPA-displayed M13 phage could perform two functions: assembly and nucleation. The engineered phage assembles various noble metals, metal oxides, and semiconducting nanoparticles into one-dimensional arrays. Furthermore, the DOPA-displayed phage triggered the nucleation and growth of gold, silver, platinum, bimetallic cobalt-platinum, and bimetallic iron-platinum nanowires. This versatile phage template enables rapid preparation of phage-based prototype devices by eliminating the screening process, thus reducing effort and time. PMID:25317741

Park, Joseph P; Do, Minjae; Jin, Hyo-Eon; Lee, Seung-Wuk; Lee, Haeshin

2014-11-12

255

Preparation and characterization of transition metal based organo-inorganic hybrid optical materials for bioassay fluorescence sensor probe  

NASA Astrophysics Data System (ADS)

High refractive index (H.R.I.) tetravalent transition metal ion coordinated with organic co-dopant to form charge transfer complexes into the optical acrylic preform. They have been fabricated with different concentrations of transition metal ions and H.R.I. organic co-dopant and characterized. The improved photo physical properties, thermal, structure, optical, and morphology of transition metal ions into the optical acrylic preform hybrid matrix were analyzed. Transition metal ions are dispersed inside the preform matrix with nanoparticles of mesophase structural organization through charge transfer complex formation. It gives a crucial role of nano-interface properties on fluorescence bright imaging and less life time. This hybrid functional optical hybrid material has high potential use in bio-assay sensor probe.

Dikshit, Asok K.; Lukose, Jijo

2013-01-01

256

Polyoxometalates Macroanions: From Self-Recognition to Functional Materials  

NASA Astrophysics Data System (ADS)

Large, hydrophilic polyoxoanions with high solubility in water and/or other polar solvents demonstrate unique solution behavior by self-assembling into single layer, hollow, spherical "blackberry"-like structures, which are obviously different from small, simple ions. These macroions cannot be treated as insoluble colloidal suspensions either because they form stable "real solutions". These inorganic macroions demonstrate some features usually Pobelieved to belong only to complex biological molecules, such as the self-recognition, chiral recognition, and chiral selection in dilute solutions. Highly negatively-charged molecular rods with almost identical structures were observed to self-assemble into their individual 'blackberry' structures, demonstrating tiny differences (e.g. charge, charge distribution, and organic ligands) could lead to self-recognition behavior. Chiral recognition behavior was understood by studying the self-assembly process in the racemic mixture solutions. Moreover, chiral organic molecules (lactic acid and tartaric acid) can be used to selectively inhibit the self-assembly process of one of the enantiomers. Meanwhile, polyoxometalate-based organic-inorganic hybrid materials demonstrate amphiphilic properties by self-assembling into vesicles and reverse vesicles in polar and non-polar solvents, respectively, and form catalytic emulsions in biphasic environments. Designed hybrid molecules can be programed to different devices with applications in fluorescence, photo-electronic conversion, molecular switch, and catalyst.

Yin, Panchao

257

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

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

Galloway, Joel M.

2008-01-01

258

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

NASA Astrophysics Data System (ADS)

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

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

2012-12-01

259

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

E-print Network

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, ...

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

2011-01-01

260

Inorganic–organic hybrid material containing ?-cage: {[H 2(en)]Co 2(ox)(V 4O 12)} n  

Microsoft Academic Search

By using an organic ligand, a new inorganic–organic hybrid compound of cobalt oxalate-vanadate, {[H2(en)]Co2(ox)(V4O12)}n1, where en=ethylenediamine, ox=oxalic acid, has been synthesized hydrothermally from V2O5,CoCl2·6H2O,H2C2O4·2H2O and en. Crystal data 1, orthorhombic, Cmcm space group, a=11.624(2), b=9.968(2), c=14.900(3) Å, R1=0.0298, wR2=0.1172. Compound 1 possesses a three-dimensional open-framework with ?-cage and is an antiferromagnetic matter.

Cheng-Ling Pan; Ji-Qing Xu; Kai-Xue Wang; Xiao-Bing Cui; Ling Ye; Zheng-Liang Lu; De-Qing Chu; Tie-Gang Wang

2003-01-01

261

Multi-objective optimization of functionally graded materials with temperature-dependent material properties  

Microsoft Academic Search

We propose a methodology for the multi-objective optimization of material distribution of functionally graded materials with temperature-dependent material properties for steady thermomechanical processes. The proposed approach focuses on metal\\/ceramic and metal\\/metal functionally graded materials, which offer great promise in high temperature and high heat flux applications. The two-dimensional quasi-static heat conduction and thermoelasticity problems are analyzed using the element-free Galerkin

Andrew J. Goupee; Senthil S. Vel

2007-01-01

262

Frictional properties of high functional gel materials  

NASA Astrophysics Data System (ADS)

The frictional behavior of the four kinds of high functional gels, which are double network (DN) gels, particle-double network gels (P-DN), shape memory gels (SMG), LA-shape memory gels (LA-SMG) and was studied. The velocity dependence looks similar for both the DN gels and the SMG, however the details of the dependence are different. The coefficient of the DN gels is smaller than that of the SMGs. The coefficient decreases as the normal force increases. This normal force dependence was observed for the DN gels previously, however for the first time for the SMGs. The velocity dependence looks similar for both the DN gels and the SMG, however the details of the dependence are different. The coefficient of the DN gels is smaller than that of the SMGs. The difference of the dependences is possibly related to the different softness by the temperature change of the gels. The temperature dependence of the coefficient of friction in LA-SMG was observed. Increase of the perpendicular load and the surface softness were influenced by coefficient of friction increase. In addition, the frictional coefficient of P-DN that different particle size was measured for the first time. The difference of the friction behavior of LA-SMG by the particle size was clear. Therefore, we show frictional coefficient of various high functional gels.

Wada, Masato; Yamada, Kohei; Yamada, Naoya; Makino, Masato; Gong, Jin; Furukawa, Hidemitsu

2014-03-01

263

Harvesting Vibrational Energy Using Material Work Functions  

NASA Astrophysics Data System (ADS)

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.

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

2014-10-01

264

Harvesting vibrational energy using material work functions.  

PubMed

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

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

2014-01-01

265

Harvesting Vibrational Energy Using Material Work Functions  

PubMed Central

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

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

2014-01-01

266

Using 17O solid-state NMR and first principles calculation to characterise structure and dynamics in inorganic framework materials.  

PubMed

The use of solid-state (17)O NMR to determine local chemical environment and to characterise oxygen dynamics is illustrated in studies of zirconium tungstate, ZrW(2)O(8), and tungsten oxide, WO(3). Simple 1D magic-angle spinning (MAS) NMR allows the chemical environments in ZrW(2)O(8) to be readily characterised, and the use of a combination of one- and two-dimensional experiments to characterise oxygen dynamics in its cubic phase is reviewed. Combining local information about structure and dynamics from NMR with long-range structural information from diffraction allows a comprehensive picture of the material to be developed. Recent work is described that uses first principles calculation of NMR parameters to probe subtle asymmetries in the WO(6) octahedra that form the structural motif in WO(3). NMR is shown to be a highly sensitive probe of local structure, allowing different models derived from high-quality neutron diffraction studies to be distinguished. The density functional theory (DFT) calculations allow clear correlations between (17)O chemical shifts and distortions of the structure to be established. PMID:18157838

Soleilhavoup, Anne; Hampson, Matthew R; Clark, Stewart J; Evans, John S O; Hodgkinson, Paul

2007-12-01

267

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  

Microsoft Academic Search

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

Mohit Gupta

2010-01-01

268

Fatigue Crack Growth Analysis Models for Functionally Graded Materials  

SciTech Connect

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.

Dag, Serkan [Department of Mechanical Engineering, Middle East Technical University, Ankara 06531 (Turkey); Yildirim, Bora [Department of Mechanical Engineering, Hacettepe University, Ankara 06800 (Turkey); Sabuncuoglu, Baris

2008-02-15

269

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

PubMed

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

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

2010-01-01

270

Nanocomposites of polymer and inorganic nanoparticles for optical and magnetic applications  

PubMed Central

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

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

2010-01-01

271

Investigations of inorganic and hybrid inorganic-organic nanostructures  

NASA Astrophysics Data System (ADS)

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.

Kam, Kinson Chihang

272

Self-Assembly Synthesis and Functionalization of Mesoporous Carbon Materials for Energy-Related Applications  

SciTech Connect

Self-Assembly Synthesis and Functionalization of Mesoporous Carbon Materials for Energy-Related Applications Sheng Dai Chemical Sciences Division, Oak Ridge National Laboratory, Oak Ridge, TN, 37831-6201 Porous carbon materials are ubiquitous in separation, catalysis, and energy storage/conversion. Well-defined mesoporous carbon materials are essential for a number of the aforementioned applications. Ordered porous carbon materials have previously been synthesized using colloidal crystals and presynthesized mesoporous silicas as hard templates. The mesostructures of these carbon materials are connected via ultrathin carbon filaments and can readily collapse under high-temperature conditions. Furthermore, these hard-template methodologies are extremely difficult to adapt to the fabrication of large-scale ordered nanoporous films or monoliths with controlled pore orientations. More recently, my research group at the Oak Ridge National Laboratory and several others around the world have developed alternative methods for synthesis of highly ordered mesoporous carbons via self-assembly. Unlike the mesoporous carbons synthesized via hard-template methods, these mesoporous carbons are highly stable and can be graphitized at high temperature (>2800?C) without significant loss of mesopores. The surface properties of these materials can be further tailored via surface functionalization. This seminar will provide an overview and perspective of the mesoporous carbon materials derived from soft-template synthesis and surface functionalization and their fascinating applications in catalysis, separation, and energy storage devices. Dr. Sheng Dai got his B.S. and M.S. degrees from Zhejiang University in 1984 and 1986, respectively. He subsequently obtained a PhD degree from the University of Tennessee, Knoxville in 1990. He is currently a Senior Staff Scientist and Group Leader of Nanomaterials Group and Center for Nanophase Materials Science of Oak Ridge National Laboratory and is also affiliated with the University of Tennessee as an adjunct professor. He is a co-author of more than 200 publications. His research interests include porous materials and their functionalization, new ionic liquids for chemical separation and materials synthesis, sol-gel synthesis and molecular imprinting of inorganic materials, and catalysis by nanomaterials especially gold nanocatalysts.

Dai, Sheng [ORNL] [ORNL

2009-01-01

273

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)

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.

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

2011-05-01

274

EDITORIAL: The 2nd International Symposium on Functional Materials  

NASA Astrophysics Data System (ADS)

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.

Lu, L.; Lai, M. O.

2007-12-01

275

Production of modern functional materials based on renewable vegetable resources  

NASA Astrophysics Data System (ADS)

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.

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

2013-05-01

276

Functional materials for microscale genomic and proteomic analyses.  

PubMed

The design of functional materials for genomic and proteomic analyses in microscale systems has begun to mature, from materials designed for capillary-based electrophoresis systems to those tailored for microfluidic-based or 'chip-based' platforms. In particular, recent research has focused on evaluating different polymer chemistries for microchannel surface passivation and improved DNA separation matrix performance. Additionally, novel bioconjugate materials designed specifically for electrophoretic separations in microscale channels are facilitating new separation modalities. PMID:11950557

Vreeland, Wyatt N; Barron, Annelise E

2002-04-01

277

A review of piezoelectric polymers as functional materials for electromechanical transducers  

NASA Astrophysics Data System (ADS)

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.

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

2014-03-01

278

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

E-print Network

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 ...

Hautier, Geoffroy (Geoffroy T. F.)

2011-01-01

279

Synthesis of novel inorganic–organic hybrid materials for simultaneous adsorption of metal ions and organic molecules in aqueous solution  

Microsoft Academic Search

In this paper, atom transfer radical polymerization (ATRP) and radical grafting polymerization were combined to synthesize a novel amphiphilic hybrid material, meanwhile, the amphiphilic hybrid material was employed in the absorption of heavy metal and organic pollutants. After the formation of attapulgite (ATP) ATRP initiator, ATRP block copolymers of styrene (St) and divinylbenzene (DVB) were grafted from it as ATP-P(S-b-DVB).

Xinliang Jin; Yanfeng Li; Cui Yu; Yingxia Ma; Liuqing Yang; Huaiyuan Hu

280

Development and investigation of functional hierarchical hybrid materials  

NASA Astrophysics Data System (ADS)

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.

Athauda, Thushara J.

281

Selective chemisorption of carbon monoxide by organic-inorganic hybrid materials incorporating cobalt(III) corroles as sensing components.  

PubMed

Twenty-one hybrid materials incorporating cobalt(III) corrole complexes were synthesized by a sol-gel process or by grafting the metallocorrole onto a mesostructured silica of the SBA-15 type. All the materials show an almost infinite selectivity for carbon monoxide with respect to dinitrogen and dioxygen in the low-pressure domain where the chemisorption phenomenon is predominant. This peculiar property is of prime importance for an application as a CO sensor. The selectivity slightly decreases at high pressures where nonselective physisorption phenomena mainly occur. The percentage of active sites for CO chemisorption ranges from 22 to 64 %. This low percentage may be attributable to interactions between the cobalt(III) corroles with silanol or siloxane groups remaining at the surface of the materials which prevent further coordination of the CO molecule. Notably, the most efficient materials are those prepared in the presence of a protecting ligand (pyridine) during the gelation or the grafting process. The removal of this ligand after the gelation process releases a cavity around the cobalt ion that favors the coordination of a carbon monoxide molecule. The CO adsorption properties of the SBA-15 hybrid were not affected over a period of several months thus indicating a high stability of the material. Conversely, the xerogel capacities slowly decrease owing to the evolution of the material structure. PMID:17143920

Barbe, Jean-Michel; Canard, Gabriel; Brandès, Stéphane; Guilard, Roger

2007-01-01

282

Higher-Order Theory for Functionally Graded Materials  

NASA Technical Reports Server (NTRS)

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.

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

2001-01-01

283

Transient multiscale thermoelastic analysis of functionally graded materials Andrew J. Goupee, Senthil S. Vel *  

E-print Network

Transient multiscale thermoelastic analysis of functionally graded materials Andrew J. Goupee homogenization Functionally graded material Transient multiscale analysis Direct micromechanical failure analysis-phase functionally graded materials within the framework of linearized thermoelasticity. The two-phase material

Vel, Senthil

284

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

NASA Technical Reports Server (NTRS)

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).

Talham, Daniel R.; Adair, James H.

2005-01-01

285

Some functional properties of composite material based on scrap tires  

NASA Astrophysics Data System (ADS)

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.

Plesuma, Renate; Malers, Laimonis

2013-09-01

286

Time-harmonic dynamic Green's functions for two-dimensional functionally graded magnetoelectroelastic materials  

NASA Astrophysics Data System (ADS)

In this study, for two-dimensional functionally graded magnetoelectroelastic materials, the explicit solutions of time-harmonic dynamic Green's functions are derived. With the coupling of the mechanical-electric-magnetic fields and material gradient properties of exponentially varying, the governing equations are presented. Different conditions on the wave number and material gradient characteristics are discussed, separately. In the numerical results, the effects of both dynamic and gradient properties on the Green's functions are presented. It is also found that the time-harmonic dynamic Green's functions tend to zero with the distance increasing.

Wang, Yi-Ze; Kuna, Meinhard

2014-01-01

287

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

E-print Network

metal [2, 3]. A more generic approach to enhance corrosion resistance is to apply protective films for corrosion protection of stainless steel T. P. CHOU Department of Materials Science and Engineering, University of Washington, Seattle, WA, USA E-mail: gzcao@u.washington.edu One of the most effective corrosion

Cao, Guozhong

288

CR3: Cornerstone to the sustainable inorganic materials management (SIM2) research program at K.U.Leuven  

NASA Astrophysics Data System (ADS)

TMS has forged cooperative agreements with several carefully selected organizations that actively work to benefit the materials science community. In this occasional series, JOM will provide an update on the activities of these organizations. This installment features the Center for Resource Recovery & Recycling (CR3), a research center established by Worcester Polytechnic Institute, Colorado School of Mines, and K.U. Leuven

Jones, P. T.; van Gerven, T.; van Acker, K.; Geysen, D.; Binnemans, K.; Fransaer, J.; Blanpain, B.; Mishra, B.; Apelian, D.

2011-12-01

289

Ionic liquids coated Fe3O4 based inorganic-organic hybrid materials and their application in the simultaneous determination of DNA bases.  

PubMed

Ionic liquids (ILs) coated Fe3O4 based inorganic-organic hybrid materials (represented as Fe3O4/ILs) were synthesized. ILs such as methylimidazolium chloride ([Hmim][Cl]) and 1-butyl-3-methylimidazolium chloride ([Bmim][Cl]) were investigated. For comparative study, quaternary ammonium salts such as choline chloride, cetyltrimethylammonium bromide [C16H33N(CH3)3][Br], and trimethylstearylammonium chloride [C18H37N(CH3)3][Cl] were also investigated. Materials were characterized by X-ray diffraction, nitrogen sorption, Fourier transform infrared and scanning/transmission electron microscopy. Electrochemical sensors based on Fe3O4/ILs modified glassy carbon electrodes were fabricated for the simultaneous determination of all four DNA bases. The electrochemical behavior of DNA bases was investigated in detail. Various reaction parameters such as effect of scan rate, number of electrons involved in the rate determining step, electron transfer coefficient, surface adsorbed concentration, and the electrode reaction standard rate constant were investigated. Catalytic activity obtained at various Fe3O4/ILs modified electrodes was explained using DFT calculation. The analytical performance of the sensor was demonstrated in the simultaneous determination of guanine, adenine, thymine, and cytosine in calf thymus DNA sample. PMID:24703634

Kaur, Balwinder; Srivastava, Rajendra

2014-06-01

290

A pilot-scale evaluation of magnetic ion exchange treatment for removal of natural organic material and inorganic anions  

Microsoft Academic Search

The objective of this research was to evaluate a magnetic ion exchange process (MIEX) for the removal of natural organic material (NOM) and bromide on a continuous-flow pilot-scale basis under different operating conditions and raw water characteristics. The most important operating variable was the effective resin dose (ERD), which is the product of the steady-state resin concentration in the contactor

Treavor H. Boyer; Philip C. Singer

2006-01-01

291

Selenium, selected inorganic elements, and organochlorine pesticides in bottom material and biota from the Colorado River delta  

Microsoft Academic Search

Concentrations of selenium (Se) in bottom material ranged from 0·6 to 5·0 lg g~1, and from 0·5 to 18·3 l gg ~1 in biota; 23% of samples exceeded the toxic threshold. Concentrations of DDE in biota exceeded the toxic threshold in 30% of the samples. Greater concentrations of selenium in biota were found at sites with strongly reducing conditions, no

Jaqueline GarcmH; Kirke A. King; Anthony L. Velasco; Evgueni Shumilin; Miguel A. MoraA; Edward P. Glenn

2001-01-01

292

Science Update: Inorganic Chemistry.  

ERIC Educational Resources Information Center

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)

Rawls, Rebecca

1981-01-01

293

Inorganic membranes: The new industrial revolution  

SciTech Connect

Separation systems are a vital part of most industrial processes. These systems account for a large fraction of the capital equipment used and the operating costs of industrial processes. Inorganic membranes have the potential for providing separation systems that can significantly reduce both the capital equipment and operating costs. These separation processes include waste management and recycle as well as the primary production of raw materials and products. The authors are rapidly learning to understand the effect of physical and chemical properties on the different transport mechanisms that occur in inorganic membranes. Such understanding can be expected to provide the information needed to design, engineer and manufacture inorganic membranes to produce very high separation factors for almost any separation function. To implement such a revolution, the authors need to organize a unique partnership between the national laboratories, and industry. The university can provide research to understand the materials and transport mechanisms that produce various separations, the national laboratories the development of an economical fabrication and manufacturing capability, and industry the practical understanding of the operational problems required to achieve inplementation.

Fain, D.E. [Martin Merietta Energy Systems, Oak Ridge, TN (United States)

1994-12-31

294

Functionalized apertures for the detection of chemical and biological materials  

DOEpatents

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.

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

295

Graphene-based materials functionalized with elastin-like polypeptides.  

PubMed

Graphene-based materials commonly require functionalization for biological applications in order to control their physical/colloidal properties and to introduce additional capabilities, such as stimuli-responsiveness and affinity to specific biomolecules. Here, we functionalized CVD-grown graphene and graphene oxide with a genetically engineered elastin-like polypeptide fused to a graphene binding peptide and then showed that the resulting hybrid materials exhibit thermo- and photoresponsive behaviors. Furthermore, we demonstrate that our genetic engineering strategy allows for the facile introduction of bioactivity to reduced graphene oxide. The stimuli-responsiveness and genetic tunability of our graphene-protein nanocomposites are attractive for addressing future biomedical applications. PMID:24512378

Wang, Eddie; Desai, Malav S; Heo, Kwang; Lee, Seung-Wuk

2014-03-01

296

Hybrid materials from agro-waste and nanoparticles: implications on the kinetics of the adsorption of inorganic pollutants.  

PubMed

This study is a first-hand report of the immobilization of Nauclea diderrichii seed waste biomass (ND) (an agro-waste) with eco-friendly mesoporous silica (MS) and graphene oxide-MS (GO + MS) nanoparticles, producing two new hybrid materials namely: MND adsorbent for agro-waste modified with MS and GND adsorbent for agro-waste modified with GO + MS nanoparticles showed improved surface area, pore size and pore volume over those of the agro-waste. The abstractive potential of the new hybrid materials was explored for uptake of Cr(III) and Pb(II) ions. Analysis of experimental data from these new hybrid materials showed increased initial sorption rate of Cr(III) and Pb(II) ions uptake. The amounts of Cr(III) and Pb(II) ions adsorbed by MND and GND adsorbents were greater than those of ND. Modification of N. diderrichii seed waste significantly improved its rate of adsorption and diffusion coefficient for Cr(III) and Pb(II) more than its adsorption capacity. The rate of adsorption of the heavy metal ions was higher with GO + MS nanoparticles than for other adsorbents. Kinetic data were found to fit well the pseudo-second-order and the diffusion-chemisorption kinetic models suggesting that the adsorption of Cr(III) and Pb(II) onto these adsorbents is mainly through chemisorption mechanism. Analysis of kinetic data with the homogeneous particle diffusion kinetic model suggests that particle diffusion (diffusion of ions through the adsorbent) is the rate-limiting step for the adsorption process. PMID:24645440

Omorogie, Martins O; Babalola, Jonathan O; Unuabonah, Emmanuel I; Gong, Jian R

2014-01-01

297

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

USGS Publications Warehouse

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.

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

1991-01-01

298

New multifunctional porous materials based on inorganic-organic hybrid single-walled carbon nanotubes: gas storage and high-sensitive detection of pesticides.  

PubMed

Single-walled carbon nanotubes (SWNTs) that are covalently functionalized with benzoic acid (SWNT-PhCOOH) can be integrated with transition-metal ions to form 3D porous inorganic-organic hybrid frameworks (SWNT-Zn). In particular, N(2)-adsorption analysis shows that the BET surface area increases notably from 645.3 to 1209.9?m(2) ?g(-1) for SWNTs and SWNT-Zn, respectively. This remarkable enhancement in the surface area of SWNT-Zn is presumably due to the microporous motifs from benzoates coordinated to intercalated zinc ions between the functionalized SWNTs; this assignment was also corroborated by NLDFT pore-size distributions. In addition, the excess-H(2)-uptake maximum of SWNT-Zn reaches about 3.1?wt.?% (12?bar, 77?K), which is almost three times that of the original SWNTs (1.2?wt.?% at 12?bar, 77?K). Owing to its inherent conductivity and pore structure, as well as good dispersibility, SWNT-Zn is an effective candidate as a sensitive electrochemical stripping voltammetric sensor for organophosphate pesticides (OPs): By using solid-phase extraction (SPE) with SWNT-Zn-modified glassy carbon electrode, the detection limit of methyl parathion (MP) is 2.3?ng?mL(-1). PMID:22865502

Wang, Feng; Zhao, Jinbo; Gong, Jingming; Wen, Lili; Zhou, Li; Li, Dongfeng

2012-09-10

299

Hybrid Materials  

E-print Network

Hybrid materials refer to any of a class of materials in which organic and inorganic components intimately mixed. This however does not mean that simple physical mixtures of organic and inorganic compounds are hybrid materials. The rider is that the mixing be at the nanometric scale. Hybrids can either be homogeneous systems of miscible organic and inorganic components or they

unknown authors

300

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

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

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

2014-06-01

301

A mesoporous 3D hybrid material with dual functionality for Hg2+ detection and adsorption.  

PubMed

Dual-function hybrid material U1 was designed for simultaneous chromofluorogenic detection and removal of Hg(2+) in an aqueous environment. Mesoporous material UVM-7 (MCM41 type) with homogeneously distributed pores of about 2-3 nm in size, a large specific surface area exceeding 1000 m(2) g(-1), and nanoscale particles was used as an inorganic support. The mesoporous solid is decorated with thiol groups that were treated with squaraine dye III to give a 2,4-bis(4-dialkylaminophenyl)-3-hydroxy-4-alkylsulfanylcyclobut-2-enone (APC) derivative that is covalently anchored to the inorganic silica matrix. The solid was characterised by various techniques including X-ray diffraction, transmission electron microscopy, Raman spectroscopy, and nitrogen adsorption. This hybrid solid is the chemodosimeter for Hg(2+) detection. Hg(2+) reacts with the APC fragment in U1 with release of the squaraine dye into the solution, which turns deep blue and fluoresces strongly. Naked-eye Hg(2+) detection is thus accomplished in an easy-to-use procedure. In contrast, U1 remains silent in the presence of other thiophilic transition metal ions, alkali and alkaline earth metal ions, or anions ubiquitously present in water such as chloride, carbonate, sulfate, and phosphate. Material U1 acts not only as chemodosimeter that signals the presence of Hg(2+) down to parts-per-billion concentrations, but at the same time is also an excellent adsorbent for the removal of mercury cations from aqueous solutions. The amount of adsorbed mercury ranges from 0.7 to 1.7 mmol g(-1), depending on the degree of functionalisation. In addition, hybrid material U1 can be regenerated for both sensing and removal purposes. As far as we know, U1 is the first example of a promising new class of polyfunctional hybrid supports that can be used as both remediation and alarm systems by selective signalling and removal of target species of environmental importance. Model compounds based on silica gel (G1), fumed silica (F1), and micrometre-sized MCM-41 scaffolds (M1) were also prepared and studied for comparative purposes. PMID:18666295

Ros-Lis, José V; Casasús, Rosa; Comes, María; Coll, Carmen; Marcos, M Dolores; Martínez-Máñez, Ramón; Sancenón, Félix; Soto, Juan; Amorós, Pedro; El Haskouri, Jamal; Garró, Nuria; Rurack, Knut

2008-01-01

302

A photometric function for diffuse reflection by particulate materials  

NASA Technical Reports Server (NTRS)

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.

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

1975-01-01

303

Functionally graded materials for impedance matching in elastic media  

NASA Astrophysics Data System (ADS)

When functionally graded material layers are inserted between two impedance mismatching media, passbands with extremely large bandwidths can appear in these layered systems. An accurate and effective iterative method is developed to deal with these layered systems with extremely large layer number.

Chen, Shi; Zhang, Yinhong; Hao, Changchun; Lin, Shuyu; Fu, Zhiqiang

2014-01-01

304

DERIVATION OF DAMAGE FUNCTIONS FOR ATMOSPHERIC DEGRADATION OF MATERIALS  

EPA Science Inventory

The information in the pape is directed to those who develop and use damage functions which relate atmospheric degradation of materials to various causal agents in the atmosphere. Such relationships must be quantified mathematically as part of the overall cost-benefit considerati...

305

Viscoelastic material functions of noncolloidal suspensions with spherical particles  

E-print Network

siloxane , incorporated with 10%­60% by volume of hollow and spherical glass beads. The material functions , Metzner 1985 , Kamal and Mutel 1985 , Khan and Prud'homme 1987 and Barnes 1989 . A significant body particles, the shear viscosity of the suspension increases with the volume fraction of the glass beads

306

Nanostructures and functional materials fabricated by interferometric lithography.  

PubMed

Interferometric lithography (IL) is a powerful technique for the definition of large-area, nanometer-scale, periodically patterned structures. Patterns are recorded in a light-sensitive medium, such as a photoresist, that responds nonlinearly to the intensity distribution associated with the interference of two or more coherent beams of light. The photoresist patterns produced with IL are a platform for further fabrication of nanostructures and growth of functional materials and are building blocks for devices. This article provides a brief review of IL technologies and focuses on various applications for nanostructures and functional materials based on IL including directed self-assembly of colloidal nanoparticles, nanophotonics, semiconductor materials growth, and nanofluidic devices. Perspectives on future directions for IL and emerging applications in other fields are presented. PMID:20976672

Xia, Deying; Ku, Zahyun; Lee, S C; Brueck, S R J

2011-01-11

307

Love wave propagation in functionally graded piezoelectric material layer.  

PubMed

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

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

2007-03-01

308

Efficient inorganic-organic hybrid perovskite solar cells based on pyrene arylamine derivatives as hole-transporting materials.  

PubMed

A set of three N,N-di-p-methoxyphenylamine-substituted pyrene derivatives have successfully been synthesized and characterized by (1)H/(13)C NMR spectroscopy, mass spectrometry, and elemental analysis. The optical and electronic structures of the pyrene derivatives were adjusted by controlling the ratio of N,N-di-p-methoxyphenylamine to pyrene, and investigated by UV/vis spectroscopy and cyclic voltammetry. The pyrene derivatives were employed as hole-transporting materials (HTMs) in fabricating mesoporous TiO2/CH3NH3PbI3/HTMs/Au solar cells. The pyrene-based derivative Py-C exhibited a short-circuit current density of 20.2 mA/cm(2), an open-circuit voltage (Voc) of 0.886 V, and a fill factor of 69.4% under an illumination of 1 sun (100 mW/cm(2)), resulting in an overall power conversion efficiency of 12.4%. The performance is comparable to that of the well-studied spiro-OMeTAD, even though the Voc is slightly lower. Thus, this newly synthesized pyrene derivative holds promise as a HTM for highly efficient perovskite-based solar cells. PMID:24313292

Jeon, Nam Joong; Lee, Jaemin; Noh, Jun Hong; Nazeeruddin, Mohammad Khaja; Grätzel, Michael; Seok, Sang Il

2013-12-26

309

An organic-inorganic hybrid semiconductor material based on Lindqvist polyoxomolybdate and a tetra-nuclear copper complex containing two different ligands.  

PubMed

A 3D organic-inorganic hybrid compound based on the Lindqvist-type polyoxometalate, [{Cu(phen)}3{Cu(?2-ox)3}{Mo6O19}] (1) (phen = 1,10-phenanthroline, ox = oxalate), has been synthesized under hydrothermal conditions and structurally characterized by elemental analysis, IR, TG, PXRD, XPS, UV-vis, and single-crystal X-ray diffraction. In compound 1, three C2O4(2-) ligands bridge one Cu atom and three Cu(phen) fragments to form a tetra-nuclear copper(II) coordination complex [{Cu(phen)}3{Cu(?2-ox)3}](2+) unit. The six-node [Mo6O19](2-) clusters are interweaved by the 6-connected tetranuclear copper(II) complex units into an intricate 3D network structure, exhibiting a 4(12)·6(3)-nbo (sodium chloride-type) topology. Compound 1 exhibits the highest connectivity of Lindqvist-type POM hybrid materials. The electrochemical behavior of 1-CPE has been investigated in detail. Furthermore, a diffuse reflectivity spectrum of 1 reveals the presence of an optical band gap and the nature of semiconductivity with a large energy gap. A magnetic susceptibility study reveals predominant antiferromagnetic interactions between the Cu(II) bridge units. PMID:24643303

Qu, Zhi-Kun; Yu, Kai; Zhao, Zhi-Feng; Su, Zhan-hua; Sha, Jing-Quan; Wang, Chun-Mei; Zhou, Bai-Bin

2014-05-14

310

Inorganic-organic hybrid framework materials: Synthesis and characterization of [{Co(H 2O)(L)} 2V 4O 12] (L = pyridine, 4-methlypyridine)  

NASA Astrophysics Data System (ADS)

Inorganic-organic hybrid materials - [{Co(H 2O)(py)} 2V 4O 12] ( 1) and [{Co(H 2O)(pic)} 2V 4O 12] (pic = 4-methylpyridine) ( 2) have been synthesized and characterized by FT-IR spectroscopy, thermogravimetric analysis, elemental analysis, manganometric titration, temperature dependent magnetic susceptibility measurement, bond valence sum calculations, and single crystal X-ray diffraction analyses. Crystals of 1- 2 have very similar structures. The two-dimensional framework structures consist of bimetallic oxide layers, composed of {VO 4} tetrahedra and {CoO 5N} octahedra bridged by oxygen atoms, with pyridine rings projecting outward on both sides of the layers. The 12 membered metallocycles - {Co 2V 4O 6} - in the layers generate cavities. The hydrophobic pyridine rings engage in ?-stacking with the aromatic rings from adjacent layers. Crystal data for 1; C 10H 14Co 2N 2O 14V 4, triclinic space group P1¯, a = 7.7952(8), b = 10.9620(11), c = 12.8778(13) ?, ? = 65.940(2), ? = 89.318(2), ? = 88.762(2), Z = 2; crystal data for 2: C 12H 18N 2Co 2O 14V 4, monoclinic space group P2 1/ m, a = 10.9361(15), b = 7.8201(11), c = 14.0224(19) ?, ? = 90.0, ? = 112.314(2), ? = 90.0, Z = 2.

Khan, M. Ishaque; Yohannes, Elizabeth; Doedens, Robert J.; Golub, Vladimir O.; O'Connor, Charles J.

2008-10-01

311

High-performance self-humidifying membrane electrode assembly prepared by simultaneously adding inorganic and organic hygroscopic materials to the anode catalyst layer  

NASA Astrophysics Data System (ADS)

A novel self-humidifying membrane electrode assembly (MEA) has been successfully prepared by adding both a hydrophilic organic polymer (polyvinyl alcohol, PVA) and an inorganic oxide (silica) to the anode catalyst layer. This MEA shows excellent self-humidification performance under low-humidity conditions. A sample containing 3 wt.% PVA and 3 wt.% silica in the anode catalyst layer achieves a current density as high as 1100 mA cm-2 at 0.6 V, and the highest peak power density is 780 mW cm-2, operating at 60 °C and 15% relative humidity for both anode and cathode. The sample also shows excellent stability at low-humidity: after 30 h of continuous operation under the same conditions, the current density decreases just slightly, from 1100 mA cm-2 to ca. 900 mA cm-2, whereas with MEAs to which only PVA or silica alone had been added, the current densities after 30 h is just 700 mA cm-2 and 800 mA cm-2, respectively. The improved self-humidification performance can be attributed to the synergistic effect of two hygroscopic materials in the anode catalyst layer.

Liang, Huagen; Dang, Dai; Xiong, Wang; Song, Huiyu; Liao, Shijun

2013-11-01

312

Functional and Multifunctional Polymers: Materials for Smart Structures  

NASA Technical Reports Server (NTRS)

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.

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

1996-01-01

313

Higher-Order Theory for Functionally Graded Materials  

NASA Technical Reports Server (NTRS)

This paper presents the full generalization of the Cartesian coordinate-based higher-order theory for functionally graded materials developed by the authors during the past several years. This theory circumvents the problematic use of the standard micromechanical approach, based on the concept of a representative volume element, commonly employed in the analysis of functionally graded composites by explicitly coupling the local (microstructural) and global (macrostructural) responses. The theoretical framework is based on volumetric averaging of the various field quantities, together with imposition of boundary and interfacial conditions in an average sense between the subvolumes used to characterize the composite's functionally graded microstructure. The generalization outlined herein involves extension of the theoretical framework to enable the analysis of materials characterized by spatially variable microstructures in three directions. Specialization of the generalized theoretical framework to previously published versions of the higher-order theory for materials functionally graded in one and two directions is demonstrated. In the applications part of the paper we summarize the major findings obtained with the one-directional and two-directional versions of the higher-order theory. The results illustrate both the fundamental issues related to the influence of microstructure on microscopic and macroscopic quantities governing the response of composites and the technologically important applications. A major issue addressed herein is the applicability of the classical homogenization schemes in the analysis of functionally graded materials. The technologically important applications illustrate the utility of functionally graded microstructures in tailoring the response of structural components in a variety of applications involving uniform and gradient thermomechanical loading.

Aboudi, Jacob; Pindera, Marek-Jerzy; Arnold, Steven M.

1999-01-01

314

Functionalized mesoporous silica materials for molsidomine adsorption: Thermodynamic study  

SciTech Connect

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.

Alyoshina, Nonna A.; Parfenyuk, Elena V., E-mail: evp@iscras.ru

2013-09-15

315

Wave propagation of functionally graded material plates in thermal environments.  

PubMed

The wave propagation of an infinite functionally graded plate in thermal environments is studied using the higher-order shear deformation plate theory. The thermal effects and temperature-dependent material properties are both taken into account. The temperature field considered is assumed to be a uniform distribution over the plate surface and varied in the thickness direction only. Material properties are assumed to be temperature-dependent, and graded in the thickness direction according to a simple power law distribution in terms of the volume fractions of the constituents. Considering the effects of transverse shear deformation and rotary inertia, the governing equations of the wave propagation in the functionally graded plate are derived by using the Hamilton's principle. The analytic dispersion relation of the functionally graded plate is obtained by solving an eigenvalue problem. Numerical examples show that the characteristics of wave propagation in the functionally graded plate are relates to the volume fraction index and thermal environment of the functionally graded plate. The influences of the volume fraction distributions and temperature on wave propagation of functionally graded plate are discussed in detail. The results carried out can be used in the ultrasonic inspection techniques and structural health monitoring. PMID:21663930

Sun, Dan; Luo, Song-Nan

2011-12-01

316

Incorporating microorganisms into polymer layers provides bioinspired functional living materials  

PubMed Central

Artificial two-dimensional biological habitats were prepared from porous polymer layers and inoculated with the fungus Penicillium roqueforti to provide a living material. Such composites of classical industrial ingredients and living microorganisms can provide a novel form of functional or smart materials with capability for evolutionary adaptation. This allows realization of most complex responses to environmental stimuli. As a conceptual design, we prepared a material surface with self-cleaning capability when subjected to standardized food spill. Fungal growth and reproduction were observed in between two specifically adapted polymer layers. Gas exchange for breathing and transport of nutrient through a nano-porous top layer allowed selective intake of food whilst limiting the microorganism to dwell exclusively in between a confined, well-enclosed area of the material. We demonstrated a design of such living materials and showed both active (eating) and waiting (dormant, hibernation) states with additional recovery for reinitiation of a new active state by observing the metabolic activity over two full nutrition cycles of the living material (active, hibernation, reactivation). This novel class of living materials can be expected to provide nonclassical solutions in consumer goods such as packaging, indoor surfaces, and in biotechnology. PMID:22198770

Gerber, Lukas C.; Koehler, Fabian M.; Grass, Robert N.; Stark, Wendelin J.

2012-01-01

317

Functionalization of Carbon Materials using the Diels-Alder Reaction.  

PubMed

A simple and efficient Diels-Alder (DA) reaction on carbon material has been demonstrated. The present work involves single and multiwall carbon nanotubes (CNTs), as well as Herringbone carbon nanofiber. The CNTs show a dual nature of reactivity in DA reaction, i.e., they behave both as dienophile and diene with furfuryl groups and maleic anhydride derivatives, respectively. Various functional groups, including alcohol, amine, epoxy, carboxylic and ester, have been introduced on the carbon materials. The results suggest that the reactivity of CNT in DA reaction may resemble the chemistry of small molecules. PMID:21590945

Munirasu, Selvaraj; Albuerne, Julio; Boschetti-de-Fierro, Adriana; Abetz, Volker

2010-03-16

318

New perspectives on calcium environments in inorganic materials containing calcium–oxygen bonds: A combined computational–experimental 43Ca NMR approach  

Microsoft Academic Search

The potential of a combined experimental–computational 43Ca solid state NMR approach for the structural analysis of different families of inorganic compounds (calcium phosphates, silicates, aluminates and borates) has been investigated. Natural-abundance 43Ca NMR data of six crystalline calcium phosphates is reported. DFT periodic calculations of 43Ca NMR parameters of an extensive number of Ca–O inorganic species have been performed, showing

Christel Gervais; Danielle Laurencin; Alan Wong; Frédérique Pourpoint; John Labram; Bleddyn Woodward; Andrew P. Howes; Kevin J. Pike; Ray Dupree; Francesco Mauri; Christian Bonhomme; Mark E. Smith

2008-01-01

319

Acid Functionalized Mesoporous Ordered Materials for the Production of 5-Hydroxymethyfurfural from Carbohydrates  

NASA Astrophysics Data System (ADS)

Solid acid catalysts were designed for the conversion of fructose to 5-hydroxymethylfurfural (HMF). Some of the catalysts incorporate thioether groups to promote the tautomerization of fructose to its furanose form, as well as sulfonic acid groups to catalyze its dehydration. A bifunctional silane, 3-((3-(trimethoxysilyl)propyl)thio)propane-1-sulfonic acid (TESAS), was designed for incorporation into SBA-15-type silica by co-condensation. To achieve mesopore ordering in the functionalized silica, the standard SBA-15 synthetic protocol was modified, resulting in well-formed hexagonal particles. Functional groups incorporated into mesoporous silica by co-condensation are more robust under the reaction conditions than those grafted onto a non-porous silica. In a variation, the thioether group of TESAS was oxidized by H2O 2 to the sulfone during the synthesis of the modified SBA-15. The materials were tested in batch reactors and compared in the selective dehydration of fructose to 5-hydroxymethylfurfural (HMF). Compared to benchmark catalysts, the thioether-containing TESAS-SBA-15 showed the highest activity in the dehydration of aqueous fructose, as well as the highest selectivity towards HMF (71 % at 84 % conversion). In addition, the stability of several supported acid catalysts was evaluated in tubular reactors designed to produce 5-hydroxymethylfurfural (HMF) continuously. The reactors, packed with the solid catalysts, were operated at 403 K for extended periods, up to 180 h. The behaviors of three propylsulfonic acid-functionalized, ordered porous silicas (one inorganic SBA-15-type silica, and two ethane-bridged SBA-15-type organosilicas) were compared with that of a propylsulfonic acid-modified, non-ordered porous silica. The HMF selectivity of the catalysts with ordered pore structures ranged from 60 to 75 %, while the selectivity of the non-ordered catalyst peaked at 20 %. The latter was also the least stable, deactivating with a first-order rate constant of 0.152 h-1. The organosilicas are more hydrothermally stable and maintained a steady catalytic activity longer than inorganic SBA-15-type silica. The organosilica with an intermediate framework ethane content of 45 mol % was the most stable, with a first-order deactivation rate constant of only 0.012 h-1. Deactivation under flow conditions is caused primarily by hydrolytic cleavage of acid sites, which can be (to some extent) recaptured by the free surface hydroxyl groups of the silica surface.

Crisci, Anthony J.

320

Metal-metalloporphyrin frameworks: a resurging class of functional materials.  

PubMed

This review presents comprehensively recent progress in metal-metalloporphyrin frameworks (MMPFs) with an emphasis on versatile functionalities. Following a brief introduction of basic concepts and the potential virtues of MMPFs, we give a snapshot of the historical perspective of MMPFs since 1991. We then summarize four effective strategies implemented frequently to construct prototypal MMPFs. MMPFs represent a resurging class of promising functional materials, highlighted with diverse applications including guest-molecule adsorption and separation, catalysis, nano-thin films and light-harvesting. PMID:24676096

Gao, Wen-Yang; Chrzanowski, Matthew; Ma, Shengqian

2014-08-21

321

Assembly of surface engineered nanoparticles for functional materials  

NASA Astrophysics Data System (ADS)

Nanoparticles are regarded as exciting new building blocks for functional materials due to their fascinating physical properties because of the nano-confinement. Organizing nanoparticles into ordered hierarchical structures are highly desired for constructing novel optical and electrical artificial materials that are different from their isolated state or thermodynamics random ensembles. My research integrates the surface chemistry of nanoparticles, interfacial assembly and lithography techniques to construct nanoparticle based functional structures. We designed and synthesized tailor-made ligands for gold, semiconductor and magnetic nanoparticle, to modulate the assembly process and collective properties of the assembled structures, by controlling the key parameters such as particle-interface interaction, dielectric environments and inter-particle coupling etc. Top-down technologies such as micro contact printing, photolithography and nanoimprint lithography are used to guide the assembly into arbitrarily predesigned structures for potential device applications.

Yu, Xi

322

Approximate Green's function methods for HZE transport in multilayered materials  

NASA Technical Reports Server (NTRS)

A nonperturbative analytic solution of the high charge and energy (HZE) Green's function is used to implement a computer code for laboratory ion beam transport in multilayered materials. The code is established to operate on the Langley nuclear fragmentation model used in engineering applications. Computational procedures are established to generate linear energy transfer (LET) distributions for a specified ion beam and target for comparison with experimental measurements. The code was found to be highly efficient and compared well with the perturbation approximation.

Wilson, John W.; Badavi, Francis F.; Shinn, Judy L.; Costen, Robert C.

1993-01-01

323

Carbon nanotubes based functional materials for MSL and biosensor applications  

Microsoft Academic Search

In this thesis, several carbon nanotubes (CNTs) based functional materials have been successfully synthesized and systematically characterized. Their applications for MicroStereoLithography (MSL) and biosensor were further explored. A new mild oxidization method for oxidizing multi-walled CNTs was developed using potassium permanganate as the oxidant and assisted with phase transfer catalyst. The novel oxidization procedure gives significantly higher yield and high

Nanyan Zhang

2005-01-01

324

Supersonic flutter analysis of thin cracked functionally graded material plates  

E-print Network

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.

Natarajan, S; Bordas, S

2012-01-01

325

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

PubMed

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

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

2014-10-01

326

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

SciTech Connect

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.

Piecha, A., E-mail: anna.piecha@chem.uni.wroc.pl [Faculty of Chemistry, University of Wroc?aw, Joliot–Curie 14, 50–383 Wroc?aw (Poland); G?gor, A. [Institute of Low Temperature and Structure Research, PAS, Okólna 2, 50–950 Wroc?aw (Poland)] [Institute of Low Temperature and Structure Research, PAS, Okólna 2, 50–950 Wroc?aw (Poland); W?c?awik, M.; Jakubas, R. [Faculty of Chemistry, University of Wroc?aw, Joliot–Curie 14, 50–383 Wroc?aw (Poland)] [Faculty of Chemistry, University of Wroc?aw, Joliot–Curie 14, 50–383 Wroc?aw (Poland); Medycki, W. [Institute of Molecular Physics, PAS, M. Smoluchowskiego 17, 60-179 Pozna? (Poland)] [Institute of Molecular Physics, PAS, M. Smoluchowskiego 17, 60-179 Pozna? (Poland)

2013-01-15

327

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

SciTech Connect

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.

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

1998-12-31

328

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)

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.

Burns, Jonathan David

329

Alkoxide routes to Inorganic Materials  

SciTech Connect

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.

Thomas, George H [ORNL

2007-12-01

330

Carbon nanotubes based functional materials for MSL and biosensor applications  

NASA Astrophysics Data System (ADS)

In this thesis, several carbon nanotubes (CNTs) based functional materials have been successfully synthesized and systematically characterized. Their applications for MicroStereoLithography (MSL) and biosensor were further explored. A new mild oxidization method for oxidizing multi-walled CNTs was developed using potassium permanganate as the oxidant and assisted with phase transfer catalyst. The novel oxidization procedure gives significantly higher yield and high functional group density. Facilitated with the above functional groups, a variety of homogeneous polymer/CNTs nanocomposites were prepared through either chemical or physical interactions and they were systematically characterized. UV curable oligomers have been attached to the wall of the oxidized carbon nanotubes, and they were cured by MicroStereoLithography (MSL) UV light laser with both free radical and cationic polymerization mechanisms. Furthermore, graphite and several CNTs-based glucose thick film biosensors are fabricated and evaluated.

Zhang, Nanyan

331

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

ERIC Educational Resources Information Center

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…

Ray, Gigi B.; Cook, J. Whitney

2005-01-01

332

PREFACE Surface Modifications and Functionalization of Materials for Biomedical Applications  

NASA Astrophysics Data System (ADS)

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)

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

2010-11-01

333

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

PubMed

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 P1¯ with the following parameters: a=8.4749(6)(?), b=17.1392(12)(?), c=17.1392(12)(?), ?=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. PMID:24967541

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

2014-12-10

334

Low work function material development for the microminiature thermionic converter.  

SciTech Connect

Thermionic energy conversion in a miniature format shows potential as a viable, high efficiency, micro to macro-scale power source. A microminiature thermionic converter (MTC) with inter-electrode spacings on the order of microns has been prototyped and evaluated at Sandia. The remaining enabling technology is the development of low work function materials and processes that can be integrated into these converters to increase power production at modest temperatures (800 - 1300 K). The electrode materials are not well understood and the electrode thermionic properties are highly sensitive to manufacturing processes. Advanced theoretical, modeling, and fabrication capabilities are required to achieve optimum performance for MTC diodes. This report describes the modeling and fabrication efforts performed to develop micro dispenser cathodes for use in the MTC.

Zavadil, Kevin Robert; Battaile, Corbett Chandler; Marshall, Albert Christian; King, Donald Bryan; Jennison, Dwight Richard

2004-03-01

335

Functionalized DNA materials for sensing and medical applications  

NASA Astrophysics Data System (ADS)

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.

Woolard, Dwight L.; Jensen, James O.

2011-06-01

336

Fluorescent Functionalized Mesoporous Silica for Radioactive Material Extraction  

SciTech Connect

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.

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

2012-08-01

337

SH SURFACE ACOUSTIC WAVE PROPAGATION IN FUNCTIONALLY GRADED PIEZOELECTRIC MATERIAL STRUCTURE WITH DISSIPATION  

E-print Network

477 SH SURFACE ACOUSTIC WAVE PROPAGATION IN FUNCTIONALLY GRADED PIEZOELECTRIC MATERIAL STRUCTURE of functionally graded piezoelectric material (FGPM) on the dispersive and attenuated characteristics of SH. Keywords: SH wave, functionally graded, viscous, dissipation, dispersion relations 315211 818 xiankai

Wang, Ji

338

Synthesis and Applications of Double-Gyroid-Structured Functional Materials  

E-print Network

2-Amino-2-hydroxymethyl-propane-1,3-diol UV Ultraviolet XPS X-ray photoelectron spectroscopy XRD X-ray diffraction xii Motivation Inspired by the work of Edward Crossland et al. on using a thin porous polymer film with double-gyroid morphology... xix 9 Summary and suggestions for further work 187 Bibliography 190 Related publications 211 A NMR spectra 213 B List of diblock copolymers 219 C SEM Images 225 xx 1 Nanostructuring of functional materials Broadly speaking, nanoscience refers to a...

Scherer, Maik

2014-05-27

339

Antimicrobial functions on cellulose materials introduced by anthraquinone vat dyes.  

PubMed

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

Zhuo, Jingyuan; Sun, Gang

2013-11-13

340

Density Functional Methods and Electronic Processes in Organic Materials  

NASA Astrophysics Data System (ADS)

When modeling the fundamental processes in organic electronic materials, ab initio calculations play an important role because they provide an independent source of information. It is thus critical to use accurate and reliable ab initio methods. In this talk, we will share our experience in using density functional methods to study charge generation and transport in some organic systems. These include prototypical polythiophene and polyfluorene, as well as some newly synthesized conjugated molecules. They all have strong dispersion forces and strong electron-vibration coupling; both are well-known difficult effects for density functional methods to capture accurately. We will describe our effort in exploring ways to do meaningful calculations. Close collaborations with experimental work will also be emphasized.

Wu, Qin

2012-02-01

341

Functionalized mesoporous silica materials for controlled drug delivery.  

PubMed

In the past decade, non-invasive and biocompatible mesoporous silica materials as efficient drug delivery systems have attracted special attention. Great progress in structure control and functionalization (magnetism and luminescence) design has been achieved for biotechnological and biomedical applications. This review highlights the most recent research progress on silica-based controlled drug delivery systems, including: (i) pure mesoporous silica sustained-release systems, (ii) magnetism and/or luminescence functionalized mesoporous silica systems which integrate targeting and tracking abilities of drug molecules, and (iii) stimuli-responsive controlled release systems which are able to respond to environmental changes, such as pH, redox potential, temperature, photoirradiation, and biomolecules. Although encouraging and potential developments have been achieved, design and mass production of novel multifunctional carriers, some practical biological application, such as biodistribution, the acute and chronic toxicities, long-term stability, circulation properties and targeting efficacy in vivo are still challenging. PMID:22441299

Yang, Piaoping; Gai, Shili; Lin, Jun

2012-05-01

342

Molecular modeling of heme proteins using MOE: Bio-inorganic and structure-function activity for undergraduates*S.  

PubMed

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 coordination chemistry. Students are asked to identify several unknown heme proteins based on a careful analysis of covalent and noncovalent interactions at the active site of each protein, focusing on amino acid reactivity and H-bonding networks. Starting with the three-dimensional crystal structures of four unknown proteins, students isolate and examine the coordination environment of the iron center in order to predict the relative reactivity toward dioxygen (O(2) ) or hydrogen peroxide (H(2) O(2) ). The central question of the project is to determine how the same iron protoporphyrin IX cofactor can be used by four different proteins to carry out diverse reactions, from electron transfer, to reversible oxygen binding to hydrogen peroxide activation. Pedagogical reasons for implementation of this biomolecular discovery-based activity and student evaluations are discussed. In addition to developing many of the three-dimensional visualization skills needed to successfully learn biochemistry, students also learn to use the versatile MOE molecular modeling program (Molecular Operating Environment), become familiar with metalloprotein reactivity, and are introduced to computational biochemistry research. PMID:21638575

Ray, Gigi B; Cook, J Whitney

2005-05-01

343

A mode decoupling continuum shape sensitivity method for fracture analysis of functionally graded materials  

E-print Network

in two-dimensional, linear-elastic, functionally graded materials with arbitrary geometry is presented Elsevier B.V. All rights reserved. Keywords: Crack; Functionally graded materials; Mode decoupling; Shape of a new class of materials called functionally graded materials (FGMs). FGMs engineered to meet a pre

Rahman, Sharif

344

Inuence of elastic gradient proles on dynamically loaded functionally graded materials: cracks along the gradient  

E-print Network

In¯uence of elastic gradient pro®les on dynamically loaded functionally graded materials: cracks reserved. Keywords: Functionally graded materials; Material nonhomogeneity; Finite element modeling; Stress intensity factors; Dynamic fracture 1. Introduction Functionally graded materials (FGMs) are known to oer

Rousseau, Carl-Ernst

345

A continuum shape sensitivity method for fracture analysis of orthotropic functionally graded materials  

E-print Network

-elastic, orthotropic functionally graded materials with arbitrary geometry. The method involves the material derivative. All rights reserved. Keywords: Crack; Orthotropic functionally graded materials; Shape sensitivity.elsevier.com/locate/mechmat #12;1. Introduction Functionally graded materials (FGMs) that possess a nonuniform microstructure

Rahman, Sharif

346

Continuum shape sensitivity analysis of a mixed-mode fracture in functionally graded materials  

E-print Network

Continuum shape sensitivity analysis of a mixed-mode fracture in functionally graded materials B-elastic functionally graded material. These methods involve the material derivative concept from conti- nuum mechanics: Crack; Functionally graded materials; Interaction integral; M-integral; Linear-elastic fracture

Rahman, Sharif

347

Bioinspiration from fish for smart material design and function  

NASA Astrophysics Data System (ADS)

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.

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

2011-09-01

348

Design and synthesis of organic-inorganic hybrid capsules for biotechnological applications.  

PubMed

Organic-inorganic hybrid capsules, which typically possess a hollow lumen and a hybrid wall, have emerged as a novel and promising class of hybrid materials and have attracted enormous attention. In comparison to polymeric capsules or inorganic capsules, the hybrid capsules combine the intrinsic physical/chemical properties of the organic and inorganic moieties, acquire more degrees of freedom to manipulate multiple interactions, create hierarchical structures and integrate multiple functionalities. Thus, the hybrid capsules exhibit superior mechanical strength (vs. polymeric capsules) and diverse functionalities (vs. inorganic capsules), which may give new opportunities to produce high-performance materials. Much effort has been devoted to exploring innovative and effective methods for the synthesis of hybrid capsules that exhibit desirable performance in target applications. This tutorial review firstly presents a brief description of the capsular structure and hybrid materials in nature, then classifies the hybrid capsules into molecule-hybrid capsules and nano-hybrid capsules based upon the size of the organic and inorganic moieties in the capsule wall, followed by a detailed discussion of the design and synthesis of the hybrid capsules. For each kind of hybrid capsule, the state-of-the-art synthesis methods are described in detail and a critical comment is embedded. The applications of these hybrid capsules in biotechnological areas (biocatalysis, drug delivery, etc.) have also been summarized. Hopefully, this review will offer a perspective and guidelines for the future research and development of hybrid capsules. PMID:24811584

Shi, Jiafu; Jiang, Yanjun; Wang, Xiaoli; Wu, Hong; Yang, Dong; Pan, Fusheng; Su, Yanlei; Jiang, Zhongyi

2014-08-01

349

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

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.

Li Ying [Department of Chemistry, Tongji University, Siping Road 1239, Shanghai 200092 (China); Yan Bing [Department of Chemistry, Tongji University, Siping Road 1239, Shanghai 200092 (China)], E-mail: byan@tongji.edu.cn

2008-05-15

350

Basis function sampling: a new paradigm for material property computation.  

PubMed

Wang-Landau sampling, and the associated class of flat histogram simulation methods have been remarkably helpful for calculations of the free energy in a wide variety of physical systems. Practically, convergence of these calculations to a target free energy surface is hampered by reliance on parameters which are unknown a priori. Here, we derive and implement a method built upon orthogonal functions which is fast, parameter-free, and (importantly) geometrically robust. The method is shown to be highly effective in achieving convergence. An important feature of this method is its ability to attain arbitrary levels of description for the free energy. It is thus ideally suited to in silico measurement of elastic moduli and other material properties related to free energy perturbations. We demonstrate the utility of such applications by applying our method to calculate the Frank elastic constants of the Lebwohl-Lasher model of liquid crystals. PMID:25415892

Whitmer, Jonathan K; Chiu, Chi-Cheng; Joshi, Abhijeet A; de Pablo, Juan J

2014-11-01

351

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

PubMed

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

Sundberg, Pia; Karppinen, Maarit

2014-01-01

352

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

PubMed Central

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

Sundberg, Pia

2014-01-01

353

Bone remodeling induced by dental implants of functionally graded materials.  

PubMed

Functionally graded material (FGM) had been developed as a potential implant material to replace titanium for its improved capability of initial osseointegration. The idea behind FGM dental implant is that its properties can be tailored in accordance with the biomechanical needs at different regions adapting to its hosting bony tissues, therefore creating an improved overall integration and stability in the entire restoration. However, there have been very few reports available so far on predicting bone remodeling induced by FGM dental implants. This article aims to evaluate bone remodeling when replacing the titanium with a hydroxyapatite/collagen (HAP/Col) FGM model. A finite element model was constructed in the buccal-lingual section of a dental implant-bone structure generated from in vivo CT scan images. The remodeling simulation was performed over a 4 year healing period. Comparisons were made between the titanium implant and various FGM implants of this model. The FGM implants showed an improved bone remodeling outcome. The study is expected to provide a basis for future development of FGM implants. PMID:19927332

Lin, Daniel; Li, Qing; Li, Wei; Swain, Michael

2010-02-01

354

Designing functionally graded materials with superior load-bearing properties.  

PubMed

Ceramic prostheses often fail from fracture and wear. We hypothesize that these failures may be substantially mitigated by an appropriate grading of elastic modulus at the ceramic surface. In this study, we elucidate the effect of elastic modulus profile on the flexural damage resistance of functionally graded materials (FGMs), providing theoretical guidelines for designing FGMs with superior load-bearing property. The Young's modulus of the graded structure is assumed to vary in a power-law relation with a scaling exponent n; this is in accordance with experimental observations from our laboratory and elsewhere. Based on the theory for bending of graded beams, we examine the effect of n value and bulk-to-surface modulus ratio (E(b)/E(s)) on stress distribution through the graded layer. Theory predicts that a low exponent (0.15materials with various n values and E(b)/E(s) ratios can be fabricated by infiltrating alumina and zirconia with a low-modulus glass. Flexural tests show that graded alumina and zirconia with suitable values of these parameters exhibit superior load-bearing capacity, 20-50% higher than their homogeneous counterparts. Improving load-bearing capacity of ceramic materials could have broad impacts on biomedical, civil, structural, and an array of other engineering applications. PMID:22178651

Zhang, Yu; Sun, Ming-Jie; Zhang, Denzil

2012-03-01

355

A review on the application of inorganic nano-structured materials in the modification of textiles: Focus on anti-microbial properties  

Microsoft Academic Search

Textiles can provide a suitable substrate to grow micro-organisms especially at appropriate humidity and temperature in contact to human body. Recently, increasing public concern about hygiene has been driving many investigations for anti-microbial modification of textiles. However, using many anti-microbial agents has been avoided because of their possible harmful or toxic effects. Application of inorganic nano-particles and their nano-composites would

Roya Dastjerdi; Majid Montazer

2010-01-01

356

High-Dielectric Constant Inorganic-Organic Hybrid Materials Prepared with Sol-Gel-Derived Crystalline BaTiO3  

Microsoft Academic Search

The preparation of ceramic\\/polymer composites (BaTiO3-polymer in particular) has received much current interest for various electronic applications, because of the possibility of combining the effect of the processability of the organic components with that of the desired electrical properties of the ceramics. The synthesis of polyimide-based inorganic-organic hybrid thin films containing crystalline BaTiO3 nanoparticles and their dielectric properties are discussed.

Nimai Chand Pramanik; Sang Il Seok

2008-01-01

357

Ab initio materials design for transparent-conducting-oxide-based new-functional materials  

Microsoft Academic Search

Based upon ab initio electronic structure calculations for delafossite CuAlO2 and ZnO, we report on the design of new-functional materials for transparent conducting oxides (TCO), such as (i) low-resistive\\u000a p-type ZnO and CuAlO2 by co-doping, (ii) high-efficiency thermoelectric power in CuAlO2 (ZT>3) by p-type doping, (iii) half-metallic ferromagnetism in transition-metal-impurity doped CuAlO2 and ZnO-based diluted magnetic semiconductors, and (iv) CaO,

H. Katayama-Yoshida; K. Sato; H. Kizaki; H. Funashima; I. Hamada; T. Fukushima; V. A. Dinh; M. Toyoda

2007-01-01

358

Enzyme-polymer hybrids for highly stanle functional materials and self-cleaning coatings.  

E-print Network

??Being deployed originally for biosynthesis or biodegradation, enzymes have also shown great potentials for development of functional materials. One particular challenge in deriving enzyme-based functional… (more)

Wu, Songtao

2011-01-01

359

Advanced Density Functional Theory Methods for Materials Science  

NASA Astrophysics Data System (ADS)

In this work we chiefly deal with two broad classes of problems in computational materials science, determining the doping mechanism in a semiconductor and developing an extreme condition equation of state. While solving certain aspects of these questions is well-trodden ground, both require extending the reach of existing methods to fully answer them. Here we choose to build upon the framework of density functional theory (DFT) which provides an efficient means to investigate a system from a quantum mechanics description. Zinc Phosphide (Zn3P2) could be the basis for cheap and highly efficient solar cells. Its use in this regard is limited by the difficulty in n-type doping the material. In an effort to understand the mechanism behind this, the energetics and electronic structure of intrinsic point defects in zinc phosphide are studied using generalized Kohn-Sham theory and utilizing the Heyd, Scuseria, and Ernzerhof (HSE) hybrid functional for exchange and correlation. Novel 'perturbation extrapolation' is utilized to extend the use of the computationally expensive HSE functional to this large-scale defect system. According to calculations, the formation energy of charged phosphorus interstitial defects are very low in n-type Zn3P2 and act as 'electron sinks', nullifying the desired doping and lowering the fermi-level back towards the p-type regime. Going forward, this insight provides clues to fabricating useful zinc phosphide based devices. In addition, the methodology developed for this work can be applied to further doping studies in other systems. Accurate determination of high pressure and temperature equations of state is fundamental in a variety of fields. However, it is often very difficult to cover a wide range of temperatures and pressures in an laboratory setting. Here we develop methods to determine a multi-phase equation of state for Ta through computation. The typical means of investigating thermodynamic properties is via 'classical' molecular dynamics where the atomic motion is calculated from Newtonian mechanics with the electronic effects abstracted away into an interatomic potential function. For our purposes, a 'first principles' approach such as DFT is useful as a classical potential is typically valid for only a portion of the phase diagram (i.e. whatever part it has been fit to). Furthermore, for extremes of temperature and pressure quantum effects become critical to accurately capture an equation of state and are very hard to capture in even complex model potentials. This requires extending the inherently zero temperature DFT to predict the finite temperature response of the system. Statistical modelling and thermodynamic integration is used to extend our results over all phases, as well as phase-coexistence regions which are at the limits of typical DFT validity. We deliver the most comprehensive and accurate equation of state that has been done for Ta. This work also lends insights that can be applied to further equation of state work in many other materials.

Demers, Steven

360

Applications of hybrid organic–inorganic nanocomposites  

Microsoft Academic Search

Organic-inorganic hybrid materials do not represent only a creative alternative to design new materials and compounds for academic research, but their improved or unusual features allow the development of innovative industrial applications. Nowadays, most of the hybrid materials that have already entered the market are synthesised and processed by using conventional soft chemistry based routes developed in the eighties. These

Clément Sanchez; Beatriz Julián; Philippe Belleville; Michael Popall

2005-01-01

361

Ion mobility studies of functional polymeric materials for fuel cells and lithium ion batteries  

NASA Astrophysics Data System (ADS)

The research presented in this thesis focuses on developing new functional polymeric materials that can conduct ions, H+, or OH - or Li+. The motivation behind this work was to understand the similarities and/or differences in the structure property relationships between polymer membranes and the conductivity of H+ and OH - ions, and between polymer membranes and the anhydrous conductivity of H+ and Li+ ions. This understanding is critical to developing durable polymer membranes with high H+, OH - and Li+ ion conductivity for proton exchange membrane fuel cells (PEMFCs), alkaline anion exchange membrane fuel cells (AAEMFCs) and lithium ion batteries respectively. Chapter 1 describes the basic functioning of PEMFCs, AAEMFCs and lithium ion batteries, the challenges associated with each research topic, and the fundamental mechanisms of ion transport. The proton conducting properties of poly(4-vinyl-1H-1,2,3-triazole) were investigated on a macroscopic scale by impedance spectroscopy and microscopic scale by solid state MAS NMR. It was found that proton conductivity is independent of molecular weight of the polymer, but influenced by orders of magnitude by the presence of residual dimethylformamide. To improve the mechanical properties of otherwise liquid-like 1H-1,2,3-triazole functionalized polysiloxane homopolymers, hybrid inorganic-organic proton exchange membranes (PEMs) containing 1H-1,2,3-triazole grafted alkoxy silanes were synthesized, using sol-gel chemistry. This method enabled self-supporting membranes having proton conductivity comparable to uncrosslinked homopolymers. One of the biggest challenges with AEMs for use in AAEMFCs is finding a cationic polyelectrolyte that is chemically stable at elevated temperatures in high pH environment. Novel triazolium ionic salts were developed, having greater chemical stability under alkaline conditions compared to existing imidazolium ionic salts. However, the chemical stability of triazolium cations was not sufficient for AAEMFC applications. Excellent chemical stability of (C5H5)2Co+ in 2 M NaOH at 80°C over 30 days was demonstrated and polymerizable vinyl functionalized cobaltocenium monomers were synthesized. This work paves the way for future development of AEMs containing cobaltocenium moieties to facilitate hydroxide ion transport. Polymers containing covalently attached cyclic carbonates were synthesized and doped with lithium triflate and their lithium ion conductivities were investigated. The findings highlight the importance of high charge carrier density and flexibility of the polymer matrix to achieve high lithium ion conductivity. These results are similar to the key factors influencing anhydrous proton transport.

Sanghi, Shilpi

362

Exact closed-form electromagnetic Green's functions for graded uniaxial multiferroic materials  

E-print Network

Exact closed-form electromagnetic Green's functions for graded uniaxial multiferroic materials X June 2008 Functionally graded multiferroic composites are being investingated in order to tailor of multiferroic materials simultaneously account for magnetization and ferroelectric polarization in a strongly

Pan, Ernie

363

Fabrication, Characterization and Modeling of Functionally Graded Materials  

NASA Astrophysics Data System (ADS)

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.

Lee, Po-Hua

364

Inorganic lead compounds in electroceramics and glasses  

SciTech Connect

Lead-based compounds are numerous. When the toxicological effects of lead compounds are studied, a distinction between organic and inorganic lead compounds appears because each group behaves differently in biological systems. Examination of inorganic lead compounds exposes additional differences in their stability, modes of human exposure and socioeconomic importance. Lead-based electroceramics and glasses include inorganic lead compounds that can be controlled in the future when restrictions on lead use are enacted. The compounds widely used in electronics pose minimal health risks because of their stability. The socioeconomic impact of restricting these compounds could be significant because of their widespread use and the difficulty of locating replacement materials.

Nair, N.; Bhalla, A.; Roy, R. [Pennsylvania State Univ., University Park, PA (United States)

1996-01-01

365

Inorganic polymers for environmental protection applications  

NASA Astrophysics Data System (ADS)

Aluminosilicate inorganic polymers have been proposed as low-energy cements since, unlike Portland cement, their production does not require high temperatures or generate large quantities of greenhouse gases. Other environmental protection applications for inorganic polymers are to encapsulate hazardous mining or radioactive wastes for safe long-term storage and as fireproof components for buildings and vehicles. However, newly developed methods for synthesising these materials have opened up the possibility of other novel environmental protection applications. These include porous cladding material for passive cooling of buildings, cost-effective exchange materials for removing heavy metals from wastewater, bacteriocidal materials for purifying polluted drinking water and materials for photodegrading hazardous organic environmental pollutants. The nature and synthesis of inorganic polymers for these environmental applications will be discussed here.

MacKenzie, K. J. D.

2011-10-01

366

Crack-tip stress fields in functionally graded materials with linearly varying properties  

E-print Network

Crack-tip stress fields in functionally graded materials with linearly varying properties N. Jain or inclined to the direction of property gradation in functionally graded materials (FGMs) are obtained com- ponent. A functionally graded material (FGM) is a composite consisting of two or more phases

Rousseau, Carl-Ernst

367

Materials Science and Engineering A251 (1998) 6476 Determination of effective elastic properties of functionally graded  

E-print Network

of functionally graded materials using Voronoi cell finite element method M. Grujicic *, Y. Zhang Program properties (the Young's modulus and the Poisson's ratio) of functionally graded materials (FGMs). Before in these `functionally graded materials' (FGMs) is lacking. One of the major reasons for this lack of knowledge

Grujicic, Mica

368

An approximate method for residual stress calculation in functionally graded materials  

E-print Network

An approximate method for residual stress calculation in functionally graded materials T.L. Becker Abstract Thermal residual stresses in functionally graded materials (FGMs) arise primarily from nonlinear. Introduction Functionally graded materials (FGMs), like other composites, are designed to achieve levels

Ritchie, Robert

369

A Mapping of the Electron Localization Function for Earth Materials  

SciTech Connect

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.

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

2005-06-01

370

Inorganic scintillators in direct dark matter investigation  

NASA Astrophysics Data System (ADS)

The discoveries, the developments and the studies that have been performed in the research of new materials and purification techniques, nowadays allow us a wide choice among inorganic scintillators for a variety of uses. In this paper the application of the inorganic crystal scintillators to direct dark matter investigation will be considered in more detail. The present framework of the detectors used at low energy for direct dark matter investigation also offers useful hints for further corollary developments.

Belli, P.; Incicchitti, A.; Cappella, F.

2014-07-01

371

Dislocation punching from interfaces in functionally-graded materials  

SciTech Connect

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.

Taya, M.; Lee, J.K. [Univ. of Washington, Seattle, WA (United States). Dept. of Mechanical Engineering] [Univ. of Washington, Seattle, WA (United States). Dept. of Mechanical Engineering; Mori, T. [Ryobi Ltd., Tokyo (Japan). Research and Development Div.] [Ryobi Ltd., Tokyo (Japan). Research and Development Div.

1997-06-01

372

Review of selected dynamic material control functions for international safeguards  

SciTech Connect

With the development of Dynamic Special Nuclear Material Accounting and Control systems used in nuclear manufacturing and reprocessing plants, there arises the question as to how these systems affect the IAEA inspection capabilities. The systems in being and under development provide information and control for a variety of purposes important to the plant operator, the safeguards purpose being one of them. This report attempts to judge the usefulness of these dynamic systems to the IAEA and have defined 12 functions that provide essential information to it. If the information acquired by these dynamic systems is to be useful to the IAEA, the inspectors must be able to independently verify it. Some suggestions are made as to how this might be done. But, even if it should not be possible to verify all the data, the availability to the IAEA of detailed, simultaneous, and plant-wide information would tend to inhibit a plant operator from attempting to generate a floating or fictitious inventory. Suggestions are made that might be helpful in the design of future software systems, an area which has proved to be fatally deficient in some systems and difficult in all.

Lowry, L.L.

1980-09-01

373

Data-mined similarity function between material compositions  

E-print Network

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 ...

Yang, Lusann

374

Functional Graphenic Materials Via a Johnson?Claisen Rearrangement  

E-print Network

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, ...

Swager, Timothy M.

375

Pulse thermal processing of functional materials using directed plasma arc  

DOEpatents

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.

Ott, Ronald D. (Knoxville, TN); Blue, Craig A. (Knoxville, TN); Dudney, Nancy J. (Knoxville, TN); Harper, David C. (Kingston, TN)

2007-05-22

376

Inorganic-organic separators for alkaline batteries  

NASA Technical Reports Server (NTRS)

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.

Sheibley, D. W. (inventor)

1978-01-01

377

Two-dimensional Thermomechanical Analysis and Optimization of Functionally Graded Materials  

E-print Network

Two-dimensional Thermomechanical Analysis and Optimization of Functionally Graded Materials Andrew optimization of heat resisting metal/ceramic functionally graded materials (FGMs). The plane stress static- tually delamination failure. One way to overcome these adverse effects is to use functionally graded

Vel, Senthil

378

New and extended parameterization of the thermodynamic model AIOMFAC: calculation of activity coefficients for organic-inorganic mixtures containing carboxyl, hydroxyl, carbonyl, ether, ester, alkenyl, alkyl, and aromatic functional groups  

NASA Astrophysics Data System (ADS)

We present a new and considerably extended parameterization of the thermodynamic activity coefficient model AIOMFAC (Aerosol Inorganic-Organic Mixtures Functional groups Activity Coefficients) at room temperature. AIOMFAC combines a Pitzer-like electrolyte solution model with a UNIFAC-based group-contribution approach and explicitly accounts for interactions between organic functional groups and inorganic ions. Such interactions constitute the salt-effect, may cause liquid-liquid phase separation, and affect the gas-particle partitioning of aerosols. The previous AIOMFAC version was parameterized for alkyl and hydroxyl functional groups of alcohols and polyols. With the goal to describe a wide variety of organic compounds found in atmospheric aerosols, we extend here the parameterization of AIOMFAC to include the functional groups carboxyl, hydroxyl, ketone, aldehyde, ether, ester, alkenyl, alkyl, aromatic carbon-alcohol, and aromatic hydrocarbon. Thermodynamic equilibrium data of organic-inorganic systems from the literature are critically assessed and complemented with new measurements to establish a comprehensive database. The database is used to determine simultaneously the AIOMFAC parameters describing interactions of organic functional groups with the ions H+, Li+, Na+, K+, NH4+, Mg2+, Ca2+, Cl-, Br-, NO3-, HSO4-, and SO42-. Detailed descriptions of different types of thermodynamic data, such as vapor-liquid, solid-liquid, and liquid-liquid equilibria, and their use for the model parameterization are provided. Issues regarding deficiencies of the database, types and uncertainties of experimental data, and limitations of the model, are discussed. The challenging parameter optimization problem is solved with a novel combination of powerful global minimization algorithms. A number of exemplary calculations for systems containing atmospherically relevant aerosol components are shown. Amongst others, we discuss aqueous mixtures of ammonium sulfate with dicarboxylic acids and with levoglucosan. Overall, the new parameterization of AIOMFAC agrees well with a large number of experimental datasets. However, due to various reasons, for certain mixtures important deviations can occur. The new parameterization makes AIOMFAC a versatile thermodynamic tool. It enables the calculation of activity coefficients of thousands of different organic compounds in organic-inorganic mixtures of numerous components. Models based on AIOMFAC can be used to compute deliquescence relative humidities, liquid-liquid phase separations, and gas-particle partitioning of multicomponent mixtures of relevance for atmospheric chemistry or in other scientific fields.

Zuend, A.; Marcolli, C.; Booth, A. M.; Lienhard, D. M.; Soonsin, V.; Krieger, U. K.; Topping, D. O.; McFiggans, G.; Peter, T.; Seinfeld, J. H.

2011-09-01

379

New and extended parameterization of the thermodynamic model AIOMFAC: calculation of activity coefficients for organic-inorganic mixtures containing carboxyl, hydroxyl, carbonyl, ether, ester, alkenyl, alkyl, and aromatic functional groups  

NASA Astrophysics Data System (ADS)

We present a new and considerably extended parameterization of the thermodynamic activity coefficient model AIOMFAC (Aerosol Inorganic-Organic Mixtures Functional groups Activity Coefficients) at room temperature. AIOMFAC combines a Pitzer-like electrolyte solution model with a UNIFAC-based group-contribution approach and explicitly accounts for interactions between organic functional groups and inorganic ions. Such interactions constitute the salt-effect, may cause liquid-liquid phase separation, and affect the gas-particle partitioning of aerosols. The previous AIOMFAC version was parameterized for alkyl and hydroxyl functional groups of alcohols and polyols. With the goal to describe a wide variety of organic compounds found in atmospheric aerosols, we extend here the parameterization of AIOMFAC to include the functional groups carboxyl, hydroxyl, ketone, aldehyde, ether, ester, alkenyl, alkyl, aromatic carbon-alcohol, and aromatic hydrocarbon. Thermodynamic equilibrium data of organic-inorganic systems from the literature are critically assessed and complemented with new measurements to establish a comprehensive database. The database is used to determine simultaneously the AIOMFAC parameters describing interactions of organic functional groups with the ions H+, Li+, Na+, K+, NH4+, Mg2+, Ca2+, Cl-, Br-, NO3-, HSO4-, and SO42-. Detailed descriptions of different types of thermodynamic data, such as vapor-liquid, solid-liquid, and liquid-liquid equilibria, and their use for the model parameterization are provided. Issues regarding deficiencies of the database, types and uncertainties of experimental data, and limitations of the model, are discussed. The challenging parameter optimization problem is solved with a novel combination of powerful global minimization algorithms. A number of exemplary calculations for systems containing atmospherically relevant aerosol components are shown. Amongst others, we discuss aqueous mixtures of ammonium sulfate with dicarboxylic acids and with levoglucosan. Overall, the new parameterization of AIOMFAC agrees well with a large number of experimental datasets. However, due to various reasons, for certain mixtures important deviations can occur. The new parameterization makes AIOMFAC a versatile thermodynamic tool. It enables the calculation of activity coefficients of thousands of different organic compounds in organic-inorganic mixtures of numerous components. Models based on AIOMFAC can be used to compute deliquescence relative humidities, liquid-liquid phase separations, and gas-particle partitioning of multicomponent mixtures of relevance for atmospheric chemistry or in other scientific fields.

Zuend, A.; Marcolli, C.; Booth, A. M.; Lienhard, D. M.; Soonsin, V.; Krieger, U. K.; Topping, D. O.; McFiggans, G.; Peter, T.; Seinfeld, J. H.

2011-05-01

380

Optimal Experiment Design for Thermal Characterization of Functionally Graded Materials.  

National Technical Information Service (NTIS)

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 p...

K. D. Cole

2003-01-01

381

New functional polymers for sensors, smart materials and solar cells  

E-print Network

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 ...

Lobez Comeras, Jose Miguel

2012-01-01

382

Functionalization of textile materials by alkoxysilane-grafted titanium dioxide  

Microsoft Academic Search

Modern materials, including textiles for specific applications, have to satisfy growing requirements. Regulations concerning\\u000a man and natural environment protection against harmful substances emission, UV radiation, and electromagnetic field radiation\\u000a become more and more stringent. Intensive development of nanotechnology offers great possibilities to create novel—conforming\\u000a to the requirements—multifunctional materials based on textile substrates. Nanoparticles of metal oxides, e.g., titania (TiO2), belong

Jadwiga Sójka-Ledakowicz; Joanna Lewartowska; Marcin Kudzin; Marcin Leonowicz; Teofil Jesionowski; Katarzyna Siwinska-Stefanska; Andrzej Krysztafkiewicz

2009-01-01

383

Developing Novel Protein-based Materials using Ultrabithorax: Production, Characterization, and Functionalization  

NASA Astrophysics Data System (ADS)

Compared to 'conventional' materials made from metal, glass, or ceramics, protein-based materials have unique mechanical properties. Furthermore, the morphology, mechanical properties, and functionality of protein-based materials may be optimized via sequence engineering for use in a variety of applications, including textile materials, biosensors, and tissue engineering scaffolds. The development of recombinant DNA technology has enabled the production and engineering of protein-based materials ex vivo. However, harsh production conditions can compromise the mechanical properties of protein-based materials and diminish their ability to incorporate functional proteins. Developing a new generation of protein-based materials is crucial to (i) improve materials assembly conditions, (ii) create novel mechanical properties, and (iii) expand the capacity to carry functional protein/peptide sequences. This thesis describes development of novel protein-based materials using Ultrabithorax, a member of the Hox family of proteins that regulate developmental pathways in Drosophila melanogaster. The experiments presented (i) establish the conditions required for the assembly of Ubx-based materials, (ii) generate a wide range of Ubx morphologies, (iii) examine the mechanical properties of Ubx fibers, (iv) incorporate protein functions to Ubx-based materials via gene fusion, (v) pattern protein functions within the Ubx materials, and (vi) examine the biocompatibility of Ubx materials in vitro. Ubx-based materials assemble at mild conditions compatible with protein folding and activity, which enables Ubx chimeric materials to retain the function of appended proteins in spatial patterns determined by materials assembly. Ubx-based materials also display mechanical properties comparable to existing protein-based materials and demonstrate good biocompatibility with living cells in vitro. Taken together, this research demonstrates the unique features and future potential of novel Ubx-based materials.

Huang, Zhao

384

Functional properties of whey protein and its application in nanocomposite materials and functional foods  

NASA Astrophysics Data System (ADS)

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.

Walsh, Helen

385

Cyclodextrin-functionalized chromatographic materials tailored for reversible adsorption.  

PubMed

Novel dendronized silica substrates were synthesized. First- and second- generation polyaryl ether dendrons were appended to silica surfaces. Using Cu(I) mediated cycloaddition "click" chemistry, ?-cyclodextrin was tethered to the dendronized surfaces and to a nondendronized surface for comparison purposes. This synthesis strategy affords a modular, versatile method for surface functionalization in which the density of functional groups can be readily varied by changing the generation of dendron used. The surfaces, which are capable of adsorbing target analytes, have been characterized and studied using X-ray photoelectron spectroscopy (XPS) and vibrational sum frequency spectroscopy (VSFS). Fluorescence spectroscopy was used to study the surfaces' ability to retain coumarin 152 (C152). These studies indicated that the ?-cyclodextrin functionalized surfaces not only adsorbed C152 but also retained it through multiple aqueous washes. Furthermore, these observations were quantified and show that substrates functionalized with first-generation dendrons have a more than 6 times greater capacity to adsorb C152 than slides functionalized with monomeric ?-cyclodextrin. The first-generation dendrons also have 2 times greater the capacity than the larger generation dendrons. This result is explained by describing a dendron that has an increased number of ?-cyclodextrin monomers but, when covalently bound to silica, has a footprint too large to optimize the number of accessible monomers. Overall, both dendronized surfaces demonstrated an increased capacity to adsorb targeted analytes over the slides functionalized with monomeric ?-cyclodextrin. The studies reported provide a methodology for characterizing and evaluating the properties of novel, highly functional surfaces. PMID:25249268

Ennist, Jessica H; Gobrogge, Eric A; Schlick, Kristian H; Walker, Robert A; Cloninger, Mary J

2014-10-22

386

Supplemental Material An MLL/COMPASS subunit functions in the C. elegans dosage compensation complex to  

E-print Network

Supplemental Material An MLL/COMPASS subunit functions in the C. elegans dosage compensation Supplemental Figure 1 ....................................................................................................................1 DPY-30 and ASH-2 antibody specificity. Supplemental Figure 2

Meyer, Barbara

387

Syntheses, structures and properties of two 2-D layered hybrid organic-inorganic materials based on different V4O12 building units.  

PubMed

Two new layered hybrid organic-inorganic compounds [Zn(pyim)]2V4O12 () (pyim = 2-(2-pyridyl)imidazole) and [Cu(bim)2]2V4O12(H2O)·CH3CH2OH () (bim = bis(1-imidazolyl)methane) based on polyoxovanadates (POVs) and organic ligands decorated transition metal units have been synthesized by hydrothermal and solvothermal methods respectively. Single crystal XRD, fluorescence spectrum, magnetic measurement, IR spectra, powder XRD and thermogravimetric (TG) measurements were performed to analyze the structures and properties of and . The structural analysis reveals that compound features a two-dimensional {[Zn(pyim)]2V4O12}n layered structure, constructed by sine wave-like {V4O12}n(4n-) chains, Zn(2+) ions and pyim ligands. In the layered structure of , {V4O12}(4-) circles are connected by Cu(2+) ions to form {Cu(V4O12)}n(2n-) chains, which are further linked by {Cu(bim)4}(2+) subunits to generate a hybrid layer of . The magnetic susceptibility measurement indicates strong antiferromagnetic interactions between Cu(2+) ions in . PMID:24154680

Hou, Wentao; Guo, Jiuyu; Xu, Xiao; Wang, Zuoxiang; Zhang, Deng; Wan, Hongxiang; Song, You; Zhu, Dunru; Xu, Yan

2014-01-14

388

High-Dielectric Constant Inorganic-Organic Hybrid Materials Prepared with Sol-Gel-Derived Crystalline BaTiO3  

NASA Astrophysics Data System (ADS)

The preparation of ceramic/polymer composites (BaTiO3-polymer in particular) has received much current interest for various electronic applications, because of the possibility of combining the effect of the processability of the organic components with that of the desired electrical properties of the ceramics. The synthesis of polyimide-based inorganic-organic hybrid thin films containing crystalline BaTiO3 nanoparticles and their dielectric properties are discussed. The precursor for the polyimide was prepared from benzophenone-3,3',4,4'-tetracarboxylic dianhydride (BTDA) and 4,4'-diamino-3,3'-dimethyl diphenyl methane (DADMDPM) and used as an organic matrix for a ceramic/polymer hybrid and that of the crystalline BaTiO3 nanoparticles was prepared by the wet-chemical decomposition of the [Ti(acac)3]+ complex with Ba(OH)2. The BaTiO3, prepared by the decomposition of the Ti-acac complex showed good crystallinity (average particle size = 90 nm) with better dispersibility in an organic medium (NMP). Crack-free thin films of 3.5-4.5 µm thickness were obtained by a single spin coating operation after curing the air-dried films at 150 °C. The polyimide/BaTiO3 hybrids exhibited a wide range of relative permittivity values (?= 3.81-31.57) at room temperature.

Pramanik, Nimai Chand; Seok, Sang Il

2008-01-01

389

2D-network of inorganic–organic hybrid material built on Keggin type polyoxometallate and amino acid: [LC 2H 6NO 2] 3[(PO 4)Mo 12O 36]·5H 2O  

Microsoft Academic Search

A new inorganic–organic hybrid material based on polyoxometallate, [L-C2H6NO2]3[(PO4)Mo12O36]·5H2O, has been successfully synthesized and characterized by single-crystal X-ray analysis, elemental analysis, infrared and ultraviolet spectroscopy, proton nuclear magnetic resonance and differential thermal analysis techniques. The title compound crystallizes in the monoclinic space group, P21\\/c, with a=12.4938 (8)Å, b=19.9326 (12)Å, c=17.9270 (11)Å, ?=102.129 (1)°, V=4364.8 (5)Å3, Z=4 and R1(wR2)=0.0513, 0.0877. The

M. H. Alizadeh; M. Mirzaei; H. Razavi

2008-01-01

390

One-dimensional inorganic-organic hybrid material [Cu(En) 2 ] 2 H 2 [{Cu(En) 2 } 2 (H 2 W 12 O 42 )] · 6.5H 2 O: Hydrothermal syntheses and crystal structure  

Microsoft Academic Search

A novel inorganic-organic hybrid material, [Cu(En)2]2H2[{Cu(En)2}2(H2W12O42)] · 6.5H2O (I) based on polyoxotungstates and Cu2+ ions, has been successfully synthesized under hydrothermal conditions and structurally characterized by single-crystal X-ray\\u000a diffraction, IR spectra, and TG analysis. Structural analysis indicates that the structure consists of a one-dimensional structure\\u000a constructed from the polyoxoanion [H2W12O42]10? bridged by {Cu(En)2}2+ groups. Each [H2W12O42]10? cluster in the polymeric

Y. Yuan; Q. S. Wang; S. M. Wang

2011-01-01

391

Inorganic trace analysis by mass spectrometry  

Microsoft Academic Search

Mass spectrometric methods for the trace analysis of inorganic materials with their ability to provide a very sensitive multielemental analysis have been established for the determination of trace and ultratrace elements in high-purity materials (metals, semiconductors and insulators), in different technical samples (e.g. alloys, pure chemicals, ceramics, thin films, ion-implanted semiconductors), in environmental samples (waters, soils, biological and medical materials)

Johanna Sabine Becker; Hans-Joachim Dietze

1998-01-01

392

Organization of zeolite microcrystals for production of functional materials.  

PubMed

This Account summarizes various methods of organizing zeolite microcrystals into two-dimensional functional entities such as monolayers, multilayers, and patterned monolayers on various substrates and three-dimensional functional entities such as microballs and protein-zeolite composite fibrils. In the case of monolayer assembly, various types of linkages and substrates, factors that govern the rate, degree of coverage, degree of close packing, degree of uniform orientation, and average binding strength between each crystal and the substrate are described. The current and future applications of the organized products are also discussed. PMID:17226943

Yoon, Kyung Byung

2007-01-01

393

Probing the nanoscale interaction forces and elastic properties of organic and inorganic materials using force-distance (F-D) spectroscopy  

NASA Astrophysics Data System (ADS)

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.

Vincent, Abhilash

394

Organic/Inorganic Complex Pigments: Ancient Colors Maya Blue  

SciTech Connect

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.

Polette-Niewold, L.A.; Manciu, F.S.; Torres, B.; Alvarado, M.; Jr.; Chianelli, R.R.

2009-06-04

395

Identifying Optimal Inorganic Nanomateirals for Hybrid Solar Cells  

SciTech Connect

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.

Xiang, H.; Wei, S. H.; Gong, X. G.

2009-01-01

396

Functionalization of biomedical materials using plasma and related technologies  

NASA Astrophysics Data System (ADS)

Plasma techniques are important to biomedical engineering and surface modification. By modifying selective surface characteristics, conventional materials can be designed with superior biological properties while the favorable bulk materials properties can be retained. In this mini-review, recent progress pertaining to surface modification of Mg-based and polymer-based biomaterials by plasma-based techniques such as gas or metal ion implantation, dual metal and gas ion implantation, as well as plasma immersion ion implantation and deposition is described. Plasma-based surface modification is promising in elevating the cell biocompatibility, blood compatibility, and antibacterial properties of Mg-based and polymer-based biomaterials and expected to be extensively applied to biomaterials.

Zhao, Ying; Yeung, Kelvin W. K.; Chu, Paul K.

2014-08-01

397

A parametric study of thermomechanical behavior of functionally gradient materials  

E-print Network

xlO 6. 638x10 8. 086x10 8. 705x10 1. 006x10 0 0 -3. 147x10 0 0 -6. 778x10 0 0 0 0 0 Table 5 Poisson's ratio of ceramics and metals (v= Pp(P tlT+ 1+ P, T+ Pq1 + PqT)) Material Pp Pl P2 Ps Zirconia Aluminum Oxide Silicon Nitride Ti...xlO 6. 638x10 8. 086x10 8. 705x10 1. 006x10 0 0 -3. 147x10 0 0 -6. 778x10 0 0 0 0 0 Table 5 Poisson's ratio of ceramics and metals (v= Pp(P tlT+ 1+ P, T+ Pq1 + PqT)) Material Pp Pl P2 Ps Zirconia Aluminum Oxide Silicon Nitride Ti...

Chin, Che-Doong

2012-06-07

398

Materials for Hydrogen Storage: From Complex Hydrides to Functionalized Nanostructures  

NASA Astrophysics Data System (ADS)

The world wide effort for a transition to renewable and clean (i.e. carbon-free) form of energy has resulted in an upsurge of interest in harnessing and utilizing Hydrogen. Apart from being the most abundant element in the universe, hydrogen offers many advantages over other fuels: it is non-toxic, clean to use, and packs more energy per mass than any other fuel. Hydrogen energy production, storage and distribution constitute a multi-disciplinary area of research. Coming to the material issues for solid state storage of hydrogen, the most desirable criteria are high storage capacity, satisfactory kinetics, and optimal thermodynamics. Complex hydrides involving light metals, such as Alanates, Imides, Borates, Amidoboranes etc. show impressive gravimetric efficiencies, although the hydrogen desorption temperatures turn out to be rather high. Apart from complex hydrides, there are other kinds of novel materials that have been investigated, e.g. carbon based materials activated with nano-catalysts, clathrate hydrates, metal-organic complexes, and more recently nanostructured cages viz. fullerenes and nanotubes decorated with simple or transition metals that serve to attract hydrogen in molecular form. In this talk, after giving a broad overview on hydrogen economy, I shall focus on first-principles design of materials for hydrogen storage, from complex hydrides to various kinds of functinalized nanostructures, and discuss the recent results obtained in our laboratory [1-6]. Some outstanding issues and challenges, like how to circumvent the problem of metal clustering on surface, or how to bring down the hydrogen desorption temperature etc. will be discussed.

Das, G. P.

2011-07-01

399

Density functional studies of functionalized graphitic materials with late transition metals for Oxygen Reduction Reactions.  

PubMed

Low-temperature fuel cells are appealing alternatives to the conventional internal combustion engines for transportation applications. However, in order for them to be commercially viable, effective, stable and low-cost electrocatalysts are needed for the Oxygen Reduction Reaction (ORR) at the cathode. In this contribution, on the basis of Density Functional Theory (DFT) calculations, we show that graphitic materials with active sites composed of 4 nitrogen atoms and transition metal atoms belonging to groups 7 to 9 in the periodic table are active towards ORR, and also towards Oxygen Evolution Reaction (OER). Spin analyses suggest that the oxidation state of those elements in the active sites should in general be +2. Moreover, our results verify that the adsorption behavior of transition metals is not intrinsic, since it can be severely altered by changes in the local geometry of the active site, the chemical nature of the nearest neighbors, and the oxidation states. Nonetheless, we find that these catalysts trend-wise behave as oxides and that their catalytic activity is limited by exactly the same universal scaling relations. PMID:21796295

Calle-Vallejo, Federico; Martínez, José Ignacio; Rossmeisl, Jan

2011-09-14

400

Engineering functional nanostructures for materials and biological applications  

NASA Astrophysics Data System (ADS)

Engineering nanostructures with complete control over the shape, composition, organization of the surface structures, and function remains a major challenge. In my work, I have fabricated nanostructures using functional polymer motifs and nanoparticles (NPs) via supramolecular and non-supramolecular interactions. In one of the approaches to generate nanostructures, I have integrated top-down approaches such as nanoimprint lithography, electron-beam lithography, and photolithography with the self-assembly (bottom-up) of NPs to provide nanostructures with tailored shape and function. In this strategy, I have developed a geometrically assisted orthogonal assembly of nanoparticles onto polymer features at precisely defined locations. This versatile NP functionalization method can be used to fabricate protein resistant patterned surfaces to provide essentially complete control over cellular alignment, making them promising biofunctional structures for cell patterning. In another approach, I have utilized self-assembly of dendrimers and NPs without preformed templates to generate nanostructures that can be used as chemoselective membranes for the separation of small and biomacromolecules.

Subramani, Chandramouleeswaran

401

Preparation and use of hybrid organic–inorganic catalysts  

Microsoft Academic Search

Various approaches towards the immobilization of molecular homogeneous catalysts are introduced, focusing on catalysts where an organic molecule is attached to the surface of an inorganic support material via a covalent bond forming the so-called hybrid organic–inorganic catalysts. The application of this new class of catalysts in a wide variety of organic reactions is reviewed.

Michael H. Valkenberg; Wolfgang F. Hölderich

2002-01-01

402

Crystallization at Inorganic-Organic Interfaces: Biominerals and Biomimetic Synthesis  

Microsoft Academic Search

Crystallization is an important process in a wide range of scientific disciplines including chemistry, physics, biology, geology, and materials science. Recent investigations of biomineralization indicate that specific molecular interactions at inorganic-organic interfaces can result in the controlled nucleation and growth of inorganic crystals. Synthetic systems have highlighted the importance of electrostatic binding or association, geometric matching (epitaxis), and stereochemical correspondence

Stephen Mann; Douglas D. Archibald; Jon M. Didymus; Trevor Douglas; Brigid R. Heywood; Fiona C. Meldrum; Nicholas J. Reeves

1993-01-01

403

Application of Patterson-function direct methods to materials characterization  

PubMed Central

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

Rius, Jordi

2014-01-01

404

The Study for Improving the Dielectric Strength and Lowering the Low-molecular-weight Siloxane of PDMS based Materials by Organic-inorganic Hybrid Method  

NASA Astrophysics Data System (ADS)

We have investigated the thermal endurance and electrical insulating properties and mechanical properties of PDMS-based hybrid materials made from ethoxy-terminated PDMS and various metal alkoxides for application as electrical insulating encapsulants. The materials exhibited good thermal stability and good electrical insulating properties. The amount of all dimethyl cyclic siloxanes evaporated at 200°C from PDMS based hybrid were found to be much lower than silicone rubber.

Aoki, Yusuke; Kubo, Hidenori; Shindou, Takuya

405

Evaluation of a Web Based Mathematics Teaching Material on the Subject of Functions  

ERIC Educational Resources Information Center

The aim of the study is to develop a web-based mathematics teaching (WBMT) material and to evaluate the effectiveness of the WBMT material for 9th grade students learning the concept of mathematical function. Firstly, a WBMT material was designed and piloted. As a result of this pilot study the site was revised as a final form. The study was…

Baki, A.; Guveli, E.

2008-01-01

406

Functionally Graded Designer Viscoelastic Materials Tailored to Perform Prescribed Tasks with Probabilistic Failures and Lifetimes  

SciTech Connect

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.

Hilton, Harry H. [Aerospace Engineering Department, Technology Research, Education and Commercialization Center, National Center for Supercomputing Applications, University of Illinois at Urbana-Champaign, 104 South Wright Street, MC-236 Urbana, IL 61801-2935 (United States)

2008-02-15

407

Evaluation of a web based mathematics teaching material on the subject of functions  

Microsoft Academic Search

The aim of the study is to develop a web-based mathematics teaching (WBMT) material and to evaluate the effectiveness of the WBMT material for 9th grade students learning the concept of mathematical function. Firstly, a WBMT material was designed and piloted. As a result of this pilot study the site was revised as a final form. The study was conducted

Adnan Baki; Ebru Güveli

2008-01-01

408

Inorganic Fullerenes, Onions, and Tubes  

NASA Astrophysics Data System (ADS)

Since the exciting and unexpected discovery of the soccerball-shaped Buckminsterfullerene (C 60 ) molecule almost two decades ago, great advances in fullerene research have been made. This includes the discovery of inorganic, noncarbon cage and nanotube structures. Of particular interest are the molybdenum and tungsten sulfides and selenides that, when viewed under an electron microscope, are remarkably similar in appearance to the more famous carbon cages and nanotubes. Among other materials capable of forming fullerene structures, nickel chloride is of importance owing to its potential nanoscale magnetic properties, while the synthesis of pure boron nitride fullerenes, with their fascinating structures, was a particular challenge. All of these materials are able to form closed cages as a result of their sheetlike structure, which can, under the right conditions, curl around and either join with an opposite edge to form a tube or roll up into a scroll. Capping of the structures is possible owing to bends in the sheets caused by the inclusion of defects: pentagons for carbon, squares and octagons for boron nitride, and triangular defects for the sulfides. Proposed applications for the inorganic fullerenes include electronic devices and storage media, probes and electron microscope tips, and nano-ball bearings and high temperature lubricants.

York, Andrew P. E.

2004-05-01

409

X-ray photoelectron spectroscopy for characterization of bionanocomposite functional materials for energy-harvesting technologies.  

PubMed

The analysis of hybrid multicomponent bioorganic and bioinorganic composite materials related to energy technologies by using X-ray photoelectron spectroscopy is discussed. The approaches and considerations of overcoming the difficulties of analyzing hybrid multicomponent materials are demonstrated for different types of materials