bluuebunny/crossref_metadata_2025 huggingface dataset:
A Novel Polymeric Approach by Utilizing Functionalized Poly(ether ether ketone) for Hydrogen Storage Applications
Authors: Pedicini Rolando , Squadrito Gaetano , Giacoppo Giosuè , Saccà Ada , Passalacqua Enza
Published: January 2010

Hydrogen is a reliable energy vector and its storage is strongly connected to the costs, performance and level of safety of the storage system components. Several materials for physical and chemical hydrogen storage have been proposed, but few research works were devoted to polymers, that generally are low cost and weight materials, easy to be managed and manufactured. In this work, a functionalised Poly(ether ether ketone) (PEEK) polymer was studied and chosen as a base polymeric matrix with the aim to produce both a low cost and low weight hydrogen storage material. The polymer was in situ functionalised starting from a manganese oxide precursor. The obtained oxide, bonded to the polymer chain, allows the hydrogen storage. In this work, the functionalisation process and preliminary results of the hydrogen storage capability are reported.

From Scanning Electron Microscopy (SEM) and surface area measurements (BET), it has been verified that the metallic compound introduction modifies the morphology of the material, supplies an increased surface area for hydrogen chemisorption, revealing a 1.2%wt/wt hydrogen adsorption capability at 77 K. Preliminary results by Gravimetric Hydrogen Absorption measurements show that by increasing the temperature, the hydrogen storage capability is reduced and a value of 0.3%wt/wt at 50°C and 80 absolute bar was obtained. The reversibility cycles of hydrogen adsorption-desorption seem to be confirmed. For this reason such approach has been considered as a promising pathway and deeper studies are in progress.
On-site sodium metal production with electrolysis by offshore wind or solar cell power generation for hydrogen generation
Authors: Murahara Masataka , Seki Kazuichi , Sato Yuji , Fujiwara Etsuo
Published: January 2010

Sodium metal reacts with water explosively to generate hydrogen. Therefore, sodium metal can have an important role as a hydrogen storage material. Seawater contains water most and sodium second. Seawater is electrolyzed by offshore wind or solar cell power generation to produce sodium; which is transported to a thermoelectric power plant on land and then is reacted with water to produce hydrogen for electric power generation. Sodium hydroxide, a by-product, is used as a raw material for soda industries. In the sodium production process, many by-products such as fresh water, magnesium, sodium hydroxide, hydrochloric acid, and sulfuric acid are produced. Thus, sodium metal is an economical, renewable, and sustainable fuel that discharges neither CO2 nor radioactivity.
Phase Formation and Hydrogen Ordering in Yttrium-Hydrogen System
Authors: Wang Ke , Hattrick-Simpers Jason , Bendersky Leonid
Published: January 2010

Phase transformations in epitaxial yttrium films grown on (0001)Ti//(0001)Al2O3 Ti-buffered sapphire substrates and hydrogenated for 10 min were characterized using transmission electron microscopy. After hydrogen charging, dense twin lamellae form during α(Y(H))-to-β(YH2) phase transition with twin boundaries predominately parallel to the interface between Y and a substrate. High densities of Shockley partial dislocations are present at the twin boundaries, their glides during phase transformation are responsible for the formation of twin lamellae. Electron diffraction from YH2 phase shows superlattice reflections, which suggests a new type of ordering on octahedral interstitial sites.
Novel Ultrathin Mg Nanoblades for Hydrogen Storage
Authors: Tang Fu , Wang Gwo Ching , Lu Toh-Ming
Published: January 2010

We describe the growth of novel ultrathin Mg crystalline nanoblades by oblique angle vapor deposition. These nanoblades were then coated with catalyst Pd and hydrogenated into magnesium hydride MgH2. In situ thermal desorption spectroscopy study showed a low H desorption temperature at ∼365 K. In situ reflection high energy electron diffraction patterns were used to study the temperature dependent structure and composition changes during the de-hydrogenation of Pd coated MgH2 nanoblades. The diffraction rings reveal the formation of alloys of Pd and Mg when the temperature is over ∼480 K. Transmission electron microscopy diffraction also supports the formation of Pd and Mg alloys. This alloying reduces the cycling capability of Mg hydride. The de-hydrogenation of MgH2 introduces a strain at the bilayer interface between MgH2 and Mg resultant from 30% volume reduction from MgH2 to Mg and formed curved nanoblades as evident by scanning electron microscopy images. Designing factors of recyclable simple hydrides will be discussed.
Molecular Vibrations as the Origin of Solid State Effects in Borohydrides
Authors: Borgschulte Andreas , Gremaud Robin , Buchter Florian , Lodziana Zbigniew , Züttel Andreas , Ramirez-Cuesta Timmy , Bardaji Miriam , Lohstroh Wiebke , Fichtner Max
Published: January 2010

In this proceeding, we discuss measurements of the vibrational properties of hydrides using inelastic neutron scattering (INS) and the impact of the vibrational modes on the thermodynamic properties. We compare the heat capacity of PdH0.63 and LiBH4 as measured calorimetrically to that derived form INS spectra. We show that the vibrational properties of Ca(BH4)2 depend on the specific phase and hitherto determine their stability.
Development of Combined Optical Cell and Sieverts-type Apparatus for in-situ Measurement of Hydrogen Storage Materials
Authors: Chiu Chun , Hattrick-Simpers Jason , Heilweil Edwin , Bendersky Leonid
Published: January 2010

A parallel high-sensitivity hydrogen sorption, and in situ Raman/IR emissivity measurement system has been developed using a stainless-steel sample cell with a sapphire window to act as a bridge between the PCT and optical measurements. The cell can be pressurized up to 4.5 MPa and heated up to 723 K. The system can measure small changes in hydrogen content, down to 0.5 μg, allowing for characterization of small quantities of powers and thin films. Hydrogen desorption in LiNH2 - LiBH4 - MgH2 nanocomposites has been studied by in-situ Raman and PCT measurement, while that of MgH2 powers and thin films has been studied by in-situ PCT and IR emissivity. In powder samples, qualitative trend is observed between changes in the Raman peak intensity/IR emissivity and the amount of hydrogen absorbed or desorbed.
Structure and Stability of Hydrogen Clathrates of Ammonia Borane
Authors: Abramov Alexander , Gutowski Maciej
Published: January 2010

Structural rules have been formulated for the molecular crystal of ammonia borane (AB, NH3BH3) and clathrates thereof. These rules are similar to the “ice rules” in water. Periodic structures of possible clathrates of AB have been predicted. A rigorous analysis of the uniform space filling tessellations of 3D space has been performed resulting in the identification of two promising structures for AB clathrates. Additional five structures have been identified exploiting features and properties of AB molecules. The screening, or evaluation, of proposed periodic structures has been performed on the basis of their stability determined at the density functional level of theory. Hydrogen capacity of the most stable periodic structure (cantitruncated cubic honeycomb) is estimated to be 21 wt%, 19% chemically bound in AB and 2 wt% of H2 physisorbed in the cages of AB.
Towards the Rational Design of Supported-Bimetallic Nanoparticle Catalysts
Authors: Dash Priyabrat , Scott Robert W. J.
Published: January 2010

Heterogeneous catalysts consisting of nanoparticles dispersed on an oxide support are a mainstay in industrial reactions, and are often made via thermal reduction of metal salts dispersed onto a pre-synthesized support. Herein we document a route towards the design of xerogel-supported nanoparticle catalysts by trapping compositionally-tuned polymer-stabilized nanoparticle precursors into sol-gel matrices. Such a route allows in principle for the tuning of the size, composition, architecture, and electronic properties of nanoparticle catalysts, which allows for the development of highly efficient and selective catalysts. As proof of concept we detail the synthesis of co-reduced PdAu nanoparticles in titania supports. The final materials are well-characterized by HRTEM and energy dispersive spectroscopy (EDS), which confirm the compositional uniformity of the nanoparticles. The importance of controlling calcination conditions in order to retain designed nanoparticle compositions is stressed; high temperature calcination conditions lead to a large degree of sintering and loss of compositional uniformity, while mild calcination temperatures can be used to retain nanoparticle compositions and sizes.
CO Oxidation Catalyzed by Pd-doped BaCeO3: Coexistence of Langmuir-Hinshelwood and BaCeO3-mediated Mechanisms
Authors: Ouyang Xiaoying , Scott Susannah
Published: January 2010

The rate law for CO oxidation over Pd-substituted BaCeO3 was studied. Under CO-rich conditions over a range of pressures and temperatures, changing reaction orders for both CO and O2 suggest the coexistence of both Langmuir-Hinshelwood and BaCeO3-mediated mechanisms. The latter dominates at high P(CO)/P(O2), while both mechanisms contribute significantly at low P(CO)/P(O2). Under CO-lean conditions, the Langmuir-Hinshelwood mechanism dominates the kinetics. The importance of the BaCeO3-mediated mechanism increases with temperature. Steady-state isotopic transient kinetic analysis (SSITKA) using 18O2 confirmed the participation of labile lattice oxygen, thus BaCeO3 behaves as a BaO-stabilized form of CeO2.
Steam Reforming of Methane on Ru and Pt Promoted Nanocomposites for SOFC Anodes
Authors: Mezentseva Natalia , Alikina Galina , Bunina Rimma , Pelipenko Vladimir , Ischenko Arcady , Smirnova Alevtina , Smorygo Oleg , Sadykov Vladislav A
Published: January 2010

Nanocomposite cermet materials comprised of NiO/YSZ (20-90 wt. %) co-promoted with SmPrCeZrO or LaPrMnCrO complex oxides and Pt, Pd or Ru were synthesized by Pechini method. These materials were characterized by BET, TEM with EDX, and CH4 TPR. The catalytic properties were studied for the steam reforming (SR) of CH4 at short contact times. Factors controlling performance of these composites in CH4 SR (Ni content, interaction between components in composites as dependent upon their chemical composition) were determined. Ru-promoted composite supported on Ni-Al foam demonstrated a high (up to 75%) methane conversion at 650° in the feed containing 20% CH4 and 40% H2O in Ar
Theoretical Analysis of the CO Oxidation Process on Neutral and Single Ionized Au18 Clusters
Authors: Castro Jorge , Soto Jorge , Molina Bertha , Calles Alipio
Published: January 2010

Experiments on the reactivity of CO for Au nanoclusters have shown a local maximum in the adsorption of the first molecule for Au18 and its cation, whereas O2 adsorption has been observed in Au18-1. In this work we present a theoretical analysis of the preferential sites for the adsorption of the CO and O2 molecules on neutral and single ionized Au18 clusters with C2v symmetry, which has been shown both theoretical and experimentally, to be the most stable isomer of the Au18 cluster. We report the results of the calculation for the binding energies of CO and O2 for non-equivalent sites and compare with the available experimental values. The oxidation mechanism is studied in first instance by the subsequent adsorption of the CO on the O2 molecule, which was previously adsorbed on the respective gold cluster. The study is based on a DFT-GGA calculation with the PW91 functional.
PVA(Polyvincyl Acohol)-assisted Hydrothermal Preparation of Bi25FeO40 and Its Photocatalytic Activity
Authors: Jianmin Li , Song Juyue , Chen Jianguo , Yu Shengwen , Jin Dengren , Cheng Jinrong
Published: January 2010

A PVA-assisted hydrothermal synthesis route was utilized to fabricate single-phase Bi25FeO40 crystallites.X-ray diffraction results indicated that sillenite Bi25FeO40 have been synthesized at the temperature of 200 ℃ using the KOH concentration of 7 M. Scanning electron microscopy showed the morphology of the as-prepared products were cubic shape with side length of 26μm. The band gap of Bi25FeO40 was determined to be 1.8 eV (688 nm) by using UV-vis diffuse reflectance spectroscopy. It was found that Bi25FeO40 exhibited a high photocatalytic activity for the degradation of methyl orange under UV-Vis irradiation, being a potential material for photocatalytic decomposition of organic contaminants.
Nitrogen-Doping Induced Optical Bandgap Widening of P-Type Cu2O Flms
Authors: Nakano Yoshitaka , Saeki Shu , Morikawa Takeshi
Published: January 2010

We have investigated the effect of N doping into Cu2O films deposited by reactive magnetron sputtering. With increasing N-doping concentration up to 3 at.%, the optical bandgap energy is enlarged from ˜2.1 to ˜2.5 eV with retaining p-type conductivity as determined by optical absorption and Hall-effect measurements. Additionally, photoelectron spectroscopy in air measurements shows an increase in the valence and conduction band shifts with N doping. These experimental results demonstrate possible optical bandgap widening of p-type N-doped Cu2O films, which is a phenomenon that is probably associated with significant structural changes induced by N doping, as suggested from x-ray diffraction measurements.
Assembly and Interfacial Effects in Hybrid Nanostructures of Zinc Oxide and Gold
Authors: Ito Daisuke , McKenzie Lallie C , Masuko Keiichiro , Hutchison James E
Published: January 2010

Gold nanoparticles were linked to ZnO films and nanowires using phosphonic and carboxylic acid ligands. TEM and STEM-HAADF characterization showed that gold nanoparticles modified with both types of ligands anchored on ZnO nanowire surfaces as well as on ZnO films. After removing the ligands from the interface between ZnO nanowires and supported gold nanoparticles, the electric conductivity in the presence of methanol vapor increased by 100 times as compared to the bare ZnO nanowire, which suggested enhanced-catalytic effects due to the hybrid structure. In addition, ZnO/Au nanomaterials were synthesized by linking ZnO nanoparticles and carboxylate-functionalized gold nanoparticles in solution. UV-vis characterization showed both the bandgap absorption from ZnO and the plasmon absorption from gold nanoparticles. Formation of hybrid nanosystems like these using organic ligands as linkers not only can lead to materials with enhanced properties but also minimize the waste of precious elements because the assembly process is an additive, rather than subtractive, process.
Photocatalytic activity of ZnO nanostructured film grown by activated reactive
Authors: Dhayalan Yuvaraj , k narasimha rao
Published: January 2010

ZnO nanostructured films were deposited at room temperature on glass substrates and cotton fabrics by activated reactive evaporation in a single step without using metal catalyst or templates. Morphological observation has shown that the nanostructured film contains seaurchin-like structures, and this seaurchin containing large number of randomly grown ZnO nanoneedles. Microstructural analysis revealed the single crystalline nature of the grown nanoneedles and their growth direction was indentified to be along [0002]. PL spectrum of nanostructured films has shown a relatively weak near-band-edge emission peak at 380 nm, and a significant broad peak at 557 nm due to the oxygen vacancy-related emission. ZnO nanostructured films grown on glass substrates and cotton fabrics have shown good photocatalytic activity against rhodamine B.
Characterization of Pore Framework Structure in Monolithic Mesoporous Silica
Authors: Wu Ching-Mao , Lin Szu-Yin , Weng Chin-Cheng , Huang Kuo-Tung
Published: January 2010

Mesoporous silica materials have received much interest due to commercial applications in chemical separations and heterogeneous catalysis. Recent studies have reported via a sol-gel nanocasting technique, monolithic mesoporous silica with wormlike pore framework could be prepared by utilizing room-temperature ionic liquids (RTILs) as templates and solvents. Although previous reports have indicated that the wormlike pores would be formed in the silica, the detailed pore network structure still remained the crucial issues to be resolved. In the present study, we investigated the pore structure in the monolithic mesoporous silica, which was templated by RTIL (1-butyl-3-methyl-imidazolium-tetrafluoroborate). We revealed an open fractal pore network with a branched and self-similar appearance was formed by the aggregation of the individual spherical pores. Transmission electron microscopy micrographs displayed that the disordered wormlike pore framework was formed in the silica. Furthermore, the small angle X-ray scattering profile measured herein further exhibited three distinct regions of power-law scattering on the respective length scales. In the high-q region, the profile followed Power behavior and a power-law of -4 was observed for the surface fractal dimension of 2, manifesting the primary pore with a smooth surface and a spherical appearance. In the intermediate-q region, a power-law of -2.5 (mass fractal dimension of 2.5), indicating an open mass fractal network was formed by the aggregation of the individual primary pores. Moreover in the low-q region, the power-law of -4 was observed for mass-fractal agglomerates of aggregates. With the proceeding analysis of unified equation in terms of two structural levels, the radiuses of gyration of primary pore (Rg1)and its aggregates (Rg2) were fitted as ca. 0.9 nm and 5.5 nm, respectively. For a spherical-model pore, the radius of pore (R) was ca. 1.16 nm; thus, the averaged pore diameter (D) was 2.32 nm. The number of primary pores in a fractal aggregate (degree of aggregation, z) was calculated as ca. 67.
Morphological Instability of Metallic Surfaces: Adsorbate Induced Nanoscale Faceting
Authors: Gupta Govind , Baier Robert , Chen Wenhua , Wang Hao , Madey Theodore E
Published: January 2010

Heterogeneous catalysis is a field of major interest in the surface science and development of new supported model catalysts with a narrow size distribution. The possibility to create narrow size distributions is to use the faceted surface structures as self assembled templates on which metal nanoclusters can grow. In the present study, new aspects of adsorbate induced faceting and nanoscale phenomena on adsorbate-covered metallic surfaces are studied on atomically-rough morphologically unstable metallic fcc (Rh) and hcp (Re) surfaces. Formation of oxygen induced faceting of atomically-rough Rh (210) surface has been studied and characterized by means of LEED, STM and AES. The LEED studies confirm the formation of three sided faceted (nanoscale pyramidal structure) Rh(210) surface when the oxygen covered Rh surface annealed to temperature higher than 550K. The facet orientations of the nanopyramid are characterized as two {731} face and a reconstructed (110) face. The excess oxygen overlayer can be removed from pyramidal faceted Rh(210) surface via catalytic reaction at low temperature using CO oxidation or H2 reaction while preserving the pyramidal structure. The average size of the nanopyramids is observed to be dependent on annealing temperature and vary from 12nm to 21nm. The atomically resolved STM images confirm the LEED observations and also revealed that (110) face of nanopyramids exhibits various reconstructions (1×n, n = 2-4) depending on oxygen coverage. Further, oxygen induced nanoscale faceted Re (12-31) surface has been formed which consist of nano-trenches (two sided ridges) with facets in (11-21) and (01-10) direction. These two- sided faceted Re (12-31) surface is used as a template to grow gold nanostructures. Under controlled growth conditions, the gold induced nanostructures are formed on oxygen induced nano-trenched Re (12-31) surface. It is observed that gold grows in the form of islands on the faceted rhenium substrate i.e. at lower coverages (≥0.8ML), it forms 2D islands whereby for higher coverages 3D islands are formed on top of the nano-ridges. The surfaces morphology of the gold covered faceted Re surface changes drastically on annealing, for the temperature >870 K, gold atoms wet the rhenium template while annealing to higher temperature (˜970K) led to the development of a three sided nanopyramids. On further annealing to higher temperatures (>1100K) cause the complete destruction of the faceted structure. LEED and STM studies revealed that the gold induced three sided nanopyramids consists of two faces of original two sided ridges with (11-20), (01-10) orientation and an additional facet in (12-32) direction. The high resolution STM images revealed that the (12-32) facet of the nanopyramid is fully decorated with single atomic zigzag gold nanochain. These faceted surfaces can be potential template for heterogeneous catalysis and development of new supported model catalysts with a narrow size distribution.
Water-soluble Poly(4-styrenesulfonic acid-co-maleic acid)-stabilized Nickel(0) and Cobalt(0) Nanoclusters as Highly Active Catalysts in Hydrogen Generation from the Hydrolysis of Ammonia-Borane
Authors: Metin Önder , Özkar Saim
Published: January 2010

Water soluble poly(4-styrenesulfonic acid-co-maleic acid), PSSA-co-MA, stabilized nickel(0) and cobalt(0) nanoclusters were prepared for the first time from the reduction of nickel(II) chloride and cobalt(II) chloride by using minimum amount of sodium borohydride shortly before their usage as catalysts in the hydrolysis of ammonia-borane (AB) in the same medium at room temperature. PSSA-co-MA stabilized nickel(0) and cobalt(0) nanoclusters showed high catalytic activity in hydrogen generation from the hydrolysis of AB even at low temperature.
Greener Synthesis of Nanoparticles Using Fine Tuned Hydrothermal Routes
Authors: Han Hyunjoo , Francesco Gianna Di , Sexton Amber , Tretiak Andrew , Maye Mathew M.
Published: January 2010

The wet chemical synthesis of energy and sensor relevant nanomaterials often requires large amounts of high boiling point solvents, grams of reactants, solvent-based purification, and the use of oxygen free atmospheres. These synthetic routes are also prone to poor scalability due to requirements of precise control of high temperatures. Because of this, the potential use of metallic nanoparticles and semiconductive quantum dots (q-dots) in energy transfer and real time biosensor applications is labor intensive and expensive. We have explored a green alternative route that involves the colloidal synthesis of CdSe and CdTe quantum dots under well-controlled hydrothermal conditions (100-200°C) using simple inorganic precursors. The resulting nanomaterials are of high quality, and are easily processed depending upon application, and their synthesis is scalable. Temperature control, and synthetic scalability is provided by the use of a synthetic microwave reactor, which employs computer-controlled dielectric heating for the rapid and controllable heating.
Mist Deposition Technique as a Green Chemical Route for Synthesizing Oxide and Organic Thin Films
Authors: Fujita Shizuo , Kaneko Kentaro , Fukui Yutaka , Nishinaka Hiroyuki , Ikenoue Takumi , Nomura Taichi
Published: January 2010

Ultrasonic spray-assisted mist deposition techniques have been developed as a cost-effective and environmental friendly deposition method for oxide and organic thin films. The chemical vapor deposition (CVD) of a variety of oxide thin films having unique functions, such as Cr2O3, Cu2O, Fe3O4, and Al2O3 thin films, has been demonstrated as well as high-quality ZnO and Ga2O3 films ever reported. In addition to the films deposition by the CVD process, the deposition of organic material thin films from the source solution has also been achieved; as examples we have shown the patterned deposition of water-soluble fluorescent polymers with a metal mask. This may substitute the spin-coating technique and contribute to increase the source consumption efficiency in the thin film deposition. We appeal that the mist deposition is a unique and promising technique as a green chemical route for film deposition.
MS2 Bacteriophage as a Biotemplate for Semiconductor Nanoparticle Synthesis
Authors: Cohen Brian A. , Kaloyeros Alain E. , Bergkvist Magnus
Published: January 2010

In this work, we demonstrate the synthesis of cadmium sulfide (CdS) nanoparticles in aqueous solution with MS2 bacteriophages as a biotemplate. Bionanofabrication methods offer unique opportunities for nanomaterials synthesis, where choice of biotemplate can influence the size, shape and function of the produced material. Synthesis reactions are carried out under mild aqueous conditions, and thus hazardous organic solvents, high temperature, and extreme pH can be avoided. The MS2 bacteriophage is a potential template system for bionanofabrication of nanoscale materials due to its size and inherent physical/chemical properties. MS2 capsid proteins can be genetically modified to incorporate functional groups and sequences. Also, genomic RNA in MS2 can be degraded or replaced with other oligonucleotide sequences and still form intact capsids. In this work, we use MS2 for bio-assisted synthesis of CdS nanoparticles and adjust the amount of RNA present in the template to assess biotemplate-nanomaterial property relationships. Produced nanoparticles were probed with several techniques including UV-Vis, photoluminescence and Hi-Res TEM. Optical techniques revealed that CdS nanoparticles with predicated fluorescent properties form in the presence of MS2 and remain stable in aqueous solutions. In fact, MS2-templated CdS nanoparticles were stable at room temperature for several weeks. Presence of RNA in the capsid interior was found to have major impact on the biotemplating process. Hi-Res TEM micrographs verified the presence of nanocrystals and their association with the biotemplate. Bionanofabrication using viral templates holds promise to enable an efficient, controlled and environmentally sustainable synthesis approach for a range of important nanomaterials. The work presented here represents an additional step forward towards those goals.
The Cytotoxicity of Quantum Dots CdSe/CdS functionalized with -COOH and –NH2
Authors: Shen Lin-Jing , Cui Jing , Liu Jin-Hua , Xu Xiao-Bo , Zhu Ming-Qiang
Published: January 2010

Recently, semiconductor nanocrystals or quantum dots (QDs) aroused great concern because of their unique properties such as the size-dependent photoluminescence. They have many excellent applications in areas of molecular bioimaging, medical detection and even energy, especially as biosensing and imaging instead of fluorescent dyes. For the bio-safety, however, we should assess the cytotoxicity of QDs before used in biomedical imaging. Here, the cytotoxicity of amino-functionalized CdSe/CdS (CdSe/CdS-NH2) QDs and carboxy-functionalized CdSe/CdS (CdSe/CdS-COOH) QDs was investigated by MTT assay method. According to our findings, both CdSe/CdS-NH2 and CdSe/CdS-COOH have a dose-dependent effect on cell proliferation. The cytotoxicity of QDs varies with storing time of QDs and kinds of cells. The cytotoxicity of QDs modified with -COOH or -NH2 groups both vary with concentrations in positive linear or change with QD storing time in negative linear. The results indicate that CdSe/CdS-COOH QDs have lower toxicity than CdSe/CdS-NH2 QDs. Hela cell is somewhat more sensitive to amino- and carboxy-modified QDs than Bel7404 cell for MTT assays.
MEMS Microresonators for High Temperature Sensor Applications
Authors: Doppalapudi Dharanipal , Mlcak Richard , LeClair Jeremie , Gwynne Patrick , Bridgham Jeffrey , Purchase Scott , Skelton Martin , Schultz Gerald , Tuller Harry
Published: January 2010

Microelectromechanical Systems (MEMS) are being extensively investigated as a means of miniaturizing piezoelectric sensors thereby offering higher sensitivity, reduced power consumption, and ability to form compact multi-sensor arrays. Such devices typically employ one or more silicon micromechanical elements (e.g. membranes, cantilever beams and tethered proof masses) driven electromechanically by a polycrystalline piezoelectric film. The use of polycrystalline materials results in inherently less stable and irreproducible device characteristics. For elevated operating temperatures, more robust and refractory materials are also required. In this paper, we describe a MEMS microresonator array capable of operating to temperatures exceeding 600°C enabled by the integration of epitaxially grown piezoelectric AlN films onto single crystal SiC tethered plates. The operation of the microresonators as sensors is illustrated by examining their response to temperature, pressure and chemical analytes.
Mechanical Characterization of Atomic Layer Deposited (ALD) Alumina for Applications in Corrosive Environments
Authors: Ou Kuang-Shun , Lin I-Kuan , Wu Ping-Hsin , Huang Zhi-Kai , Chen Kuo-Shen , Zhang Xin
Published: January 2010

In this work, thin ALD alumina films were fabricated for evaluating their capabilities as a barrier material for corrosive environments. The fracture toughness and the corrosion-resisting properties after fatigue cycle of these thin ALD alumina films have been characterized. Indentation tests indicate that the ALD alumina/Al structures could enhance both the yield strength of the metal and the effective fracture toughness of the coated ALD alumina films and this result could be useful for designing nanocomposite structures. However, the test results also indicate that the interfacial strength of the ALD/Al structures was prone to degrade under fatigue loading under corrosive environment. This could potentially be a problem for the long term reliability of related devices operated under a harsh environment. In addition, the strong correlation between indentation behavior and fatigue loading for the structure indicate that nanoindentation response could be possibly used to indicate the damage level of microstructures for future reliability evaluations.
Synthesis and Characterization of Nanocomposite Thin Films for MEMS Applications
Authors: Das Kaushik , Park Cheol , Le Faive Rosemary , Hubert Pascal , Vengallatore Srikar
Published: January 2010

Reinforcement with nanotubes, nanofibers, and nanoparticles is an attractive option for enhancing the properties of micromachined polymeric structures employed in microelectromechanical systems (MEMS). Calculations based on Eshelby-Mori-Tanaka micromechanics predict that the elastic modulus and wave velocity can be increased by over an order of magnitude by reinforcing polymers with aligned, dispersed, single-walled carbon nanotubes (SWNT). Motivated by this prediction, we measured the elastic moduli of polyimide films reinforced with SWNT at volume fractions ranging from 0 to 10%. For dilute composites, the elastic modulus increased with increasing nanotube loading from 2.5 GPa for the neat polymer to 3.5 GPa for a nanocomposite containing 0.5 vol% of SWNT. However, with further increase in the nanotube content, the elastic modulus remained essentially constant even for high loadings of 10 vol% of SWNT. In addition, significantly different elastic moduli were measured for specimens containing the same volume fraction (0.5 vol%) of SWNT produced by two different processes.
Stumbling on Extrinsic Effects in Super-hard Nanobuttons
Authors: Rinaldi Antonio , Peralta Pedro , Friesen Cody , Nahar Dhiraj , Licoccia Silvia , Traversa Enrico , Sieradzki Karl
Published: January 2010

The compressive plastic strength of nanosized single crystal metallic pillars is known to depend on the diameter D, but little attention has been given to the pillar height h. The important role of h is analyzed here, observing the suppression of generalized crystal plasticity below a critical value hCR that can be estimated a priori. Novel in-situ compression tests on regular pillars (D = 300-900 nm) as well as nanobuttons (i.e. very short pillars with h less than hCR, such as D = 200 nm and h < 120 nm in this case) show that the latter ones are exceedingly harder than ordinary Ni pillars, withstanding stresses greater than 2 GPa. This h-controlled transition in the plastic behaviour is accompanied by extrinsic plastic effects in the harder nanobuttons. Such effects normally arise as Saint-Venant’s assumption ceases to be accurate. Some bias related to those effects is identified and removed from test data. Our results underline that nanoscale testing is challenging when current methodology and technology are pushed to the limit.
Minoritary Transport in Heavily Doped p-type InGaAs
Authors: Tea Eric , Aniel Frederic
Published: January 2010

Minoritary carrier’s transport properties are of fundamental importance in the HBT’s physics. The base transit time is a key parameter to improve microwave figure of merit. Some recent minoritary electron mobilities measurements versus acceptor doping level using magneto transport method exhibit a dramatic increase at very high majority carrier concentration. This effect has been attributed to the coupling of polar optical phonons with hole plasmons (LOPC) which controls the balance between enegy gain by electric field acceleration and energy loss by polar optical phonon emission. We present minoritary mobilities as a function of majority carrier doping calculated in the frame of electrons and holes Monte Carlo modelling including LOPC.
Formation of Elemental Distribution in Glass Using Thermal Accumulation with Femtosecond Laser Irradiation
Authors: Shimizu Masahiro , Miura Kiyotaka , Yasuda Naomi , Sakakura Masaaki , Kanehira Shingo , Nishi Masayuki , Shimotsuma Yasuhiko , Hirao Kazuyuki
Published: January 2010

Elemental migration inside a glass was induced space-selectively and microscopically by high-repetition femtosecond(fs) laser irradiation. The tendency of the elemental migration depended on the strength of the bond between cations and oxygen ions:strongly bonded ions like Si or Al migrated to the center of the irradiated spot, whereas weekly bonded ions such as Ca migrated to the outside. Judged from analyzed temperature distribution, this phenomenon may be due to the thermomigration(Soret effect). The refractive index distribution was modified locally by controlling elemental distribution and optical waveguide was formed in phosphate and borate glasses.
Evolution of the Women in Materials Program: a Collaboration between Simmons College and the Cornell Center for Materials Research
Authors: Goldberg Velda , Soltzberg Leonard J. , Kaplan Michael D. , Gurney Richard W. , Lee Nancy E. , Malliaras George G. , Schember Helene R.
Published: January 2010

The Women in Materials (WIM) program is an on-going collaboration between Simmons College and the Cornell Center for Materials Research (CCMR). Beginning in 2001, during the initial four years of the project, materials-related curricula were developed, a new joint research project was begun, and nearly 1/2 of Simmons College science majors participated in materials-related research during their first two years as undergraduates. We have previously reported the student outcomes as a result of this initial stage of the project, demonstrating a successful partnership between a primarily undergraduate women's college and a federally funded Materials Research Science and Engineering Center. Here, we report the evolution and impact of this project over the last three years, subsequent to the initial seed funding from the National Science Foundation. The Women in Materials project is now a key feature of the undergraduate science program at Simmons College and has developed into an organizing structure for materials-related research at the College. Initially, three faculty members were involved and now eight faculty members from all three laboratory science departments participate (biology, chemistry, and physics). The program now involves research related to optoelectronics, polymer synthesis, biomaterials, and green chemistry, and each semester about 80% of the students who participate in these projects are 1st and 2nd year science majors. This structure has led to enhanced funding within the sciences, shared instrumentation facilities, a new minor in materials science, and a spirit of collaboration among science faculty and departments. It has also spawned a new, innovative curricular initiative, the Undergraduate Laboratory Renaissance, now in its second year of implementation, involving all three laboratory science departments in incorporating actual, on-going research projects into introductory and intermediate science laboratories. Most importantly, the Women in Materials program has embedded materials-related research into our science curriculum and has deepened and broadened the educational experience for our students; the student outcomes speak to the program's success. Approximately 70% of our science majors go on to graduate school within two years of completing their undergraduate degree. Our students also have a high acceptance rate at highly competitive summer research programs, such as Research Experience for Undergraduates (REU) programs funded by the National Science Foundation.
Confined Smart Hydrogels for Applications in Chemomechanical Sensors for Physiological Monitoring
Authors: Magda Jules J. , Lin Genyao , Tathireddy Prashant , Orthner Michael , Solzbacher Florian , Schulz Volker , Guenther Margarita
Published: January 2010

A “smart” hydrogel is a crosslinked polymer network that reversibly swells and absorbs water in response to an external stimulus such as change in pH or in the concentration of some analyte such as glucose. Microscopically-thin smart hydrogels can be combined with microfabricated piezoresistive pressure transducers to obtain “chemomechanical sensors” that serve as selective and versatile wireless biomedical sensors. Proof-of-concept is shown here using glucose- and pH-responsive hydrogels.
Active Surface Topographies in Constrained Hydrogel Films
Authors: Ortiz Ophir , Vidyasagar Ajay , Toomey Ryan
Published: January 2010

Periodic wrinkles or corrugations can appear on the free surfaces of constrained hydrogel films. The constraint generates a residual compressive stress that is partially relieved through deviation of free surfaces from a planar configuration. The morphology, amplitude and wavelength of the surface instability are generally well-defined and depend on the strength of the constraint. If swelling of the hydrogel overcomes the constraint, the film can slip along its substrate, altering the resultant compressive stress and surface topography. By tuning this slippage, we aim to direct the surface features presented by thin hydrogel films. Active control of surface morphology could have important implications in several applications ranging from sensors to controlled cell attachment and detachment.

In this work, we discuss a method of tuning the amount of slippage and surface topography of patterned poly(N-isopropylacrylamide) (poly-NIPAAm) films. The films were fabricated from photo-crosslinkable polymers comprising NIPAAm and photo-active methacroyloxy-benzophenone (MaBP) monomers. The patterned films were anchored to a substrate through a hydrogen-bonding self-assembled monolayer. The relationship between pattern geometry, pattern dimensions, and solvent were investigated with respect to the mechanical instability generated at the free surface. We observed that the wavelength, width, and amplitude of the instability always increased with the thickness of the polymer pattern. The morphology of the surface instability, however, was especially sensitive to thickness of the pattern, the solvent, and the spatial position with respect to the edge of polymer pattern. If the slippage of the film against the substrate is minimal, a wrinkle pattern in the form of bicusps was observed. If the compressive stress exceeded the hydrogen-bonding anchors, slippage of the film generated either a blister pattern or a honeycomb pattern.
Synthesis and Characterization of Peptidomimetic Self-Assembled Biodegradable Nanoparticles
Authors: Mercado-Pagán Àngel E. , Jabbari Esmaiel
Published: January 2010

Nanoparticles (NPs) are being used extensively for tumor drug delivery. These devices offer the advantage of their size, protection of the encapsulated species, and biodegradability to prevent accumulation in the interstitium. Our laboratory has synthesized polylactide fumarate (PLAF, PLGF) macromers capable of self-assembling into biodegradable and biocompatible NPs with average particle size of 280 nm. To assess the possibility of further decreasing the particle size and distribution of PLGF NPs, the polymers were conjugated with the peptide sequence Cys-Val-Val-Val-Val-Val-Val-Lys-Lys (CV6K2), which is known to self-assemble in aqueous solution into vesicles of about 50-60 nm in size. The results indicate that the PLGF-CV6K2 conjugates are capable of self-assembling into NPs of 100 nm in diameter. The NPs are proposed as having a bilayer structure, with peptide chains facing the aqueous environment and the polymer chains compacted in an internal hydrophobic layer. Degradation kinetics and release profiles show that the NPs could effectively retain and release Paclitaxel up to 30 days until completely degraded. The NPs act as reservoirs for sustained release of the active agent by diffusion and degradation of the matrix when taken up by tumor cells.
Disability from a Christian Gospel Perspective
Authors: Watts Graeme
Published: January 2010

In response to the needs of people with a disability, the contemporary Christian church has adopted policies and programmes directed towards acceptance and inclusion in the mainstream environment. At the same time, there has been a candid acknowledgement that there remain not only architectural and financial challenges but also barriers based on attitude, misconception and even theological grounds. With regard to people with a disability, texts of the Christian gospels can be interpreted as carrying mixed messages. While there are passages of comfort and acceptance, there are others which seemingly link disability with moral imperfection, as punishment for the sins of parents or simply as a test of faith in God. It is instructive to examine such gospel references from the perspective of people with a disability. Reactions can sometimes be surprisingly bitter with people with disabilities referring to themselves as humiliated and victims of fear and prejudice. At the very least, it would be helpful to recognize that the potential exists for mixed messages to be drawn from passages referring to people with a disability and that there are negative connotations to be addressed.
Roland Boer, Symposia: Dialogues Concerning the History of Biblical Interpretation.
Authors: Avrahami Yael
Published: January 2010

Roland Boer, Symposia: Dialogues Concerning the History of Biblical Interpretation. Equinox, London, 2007, pp. xi + 153, ISBN 1-84553-102-7 (pbk).
Michael B. Dick, Reading the Old Testament: An Inductive Introduction.
Authors: Young Ian
Published: January 2010

Michael B. Dick, Reading the Old Testament: An Inductive Introduction. Hendrickson, Peabody, MA, 2008, pp. xxii+367, ISBN 9781565639539. R
Christopher Deacy and Gaye Williams Ortiz, Theology and Film: Challenging the Sacred/Secular Divide.
Authors: Kozlovic Anton Karl
Published: January 2010

Christopher Deacy and Gaye Williams Ortiz, Theology and Film: Challenging the Sacred/Secular Divide. Blackwell, Malden, MA, 2008, pp. xiv+245, ISBN 978-1-4051-4438-4 (pbk).
‘Leaving the Fold’
Authors: Adam Raoul J.
Published: January 2010

This paper re-examines the direction of religious development implicit in Piagetian-based theories in light of a recent study of apostasy from fundamentalism. The theory-led and inductive thematic analysis of apostate narratives reveals evidence of a ‘sociocognitive conflict’ that complicates the implicit teleology of traditional theories of religious development. The diverse trajectories produced by this interaction between sociocultural and cognitive influences prompts a fresh analysis of Howard Gruber’s question concerning the direction of development: Which way is up? I highlight the complex interaction between cultural and cognitive influences involved in apostasy from fundamentalism and provide support for Streib’s Religious Styles Perspective as a theory for investigating multiple factors influencing the conceptualisation and direction of religious development.
Charismatic Revival and Precarious Charisma
Authors: Hunt Stephen J.
Published: January 2010

Following the neo-Pentecostal revivals of the 1990s, and commencing in the Spring of 2008, a fresh wave of revival, characterised by miraculous healings, became associated with what came to be known as the ‘Florida Outpouring’. Unlike the earlier so-called Toronto Blessing and the Brownsville revivals, that at Lakeland, Florida, proved to be relatively short-lived. While similar to the earlier revivals in many respects, it differed in being predominantly led by an individual of outstanding personal charisma, the healing evangelist, Todd Bentley, whose name became practically synomanous with the ‘Outpouring’. This paper identifies the source of Bentley’s charisma that drove the revival but which proved to be ‘precarious’. The paper then proceeds to trace the ‘Outpouring’s’ rapid decline as a result of various factors, not least of through an equally speedily discrediting of its charismatic leadership.
The Silence of Spirituality within Sociology of Childbirth
Authors: Possamai-Inesedy Alphia
Published: January 2010

A slow-pace spiritual revolution is occurring ‘right under our noses’. There is an increasing realization that the belief in an authentic spiritual reality, often outside of the Church, is growing among the mainstream population. This growth of a spiritual reality is reflected among various academic disciplines—psychology, religious studies, midwifery and anthropology are but a few examples. However, it appears largely absent within sociology of childbirth and only in an ‘infantile’ stage within sociology of religion. This is surprising considering the extensive research spanning multiple decades across the two fields. It leaves one to question whether the lack of research on spirituality is an actual reflection of the lived experience of the individual or a reflection of the epistemological and methodological terrain of the discipline itself. To better understand this, an historical overview is presented on the research carried out within sociology of childbirth and religion. It is argued that there is a twofold reason behind this silence. First is the domination of theoretical concerns around very specific issues within both fields of the discipline—namely medicalization and secularization. The second relates to the methodologies employed, more specifically within sociology of religion. While the sociology of childbirth has at its disposal the methodological tools necessary to study spirituality it appears that it lacks the paradigm that is open to the study. Paradoxically, sociology of religion possesses the required paradigm but requires the expansion of its methodological tools to develop its study into the field.