Showing papers on "Chemical binding published in 2005"

Effect of surface roughness on the adhesion properties of Cu/Cr films on polyimide substrate treated by inductively coupled oxygen plasma

Abstract: For fabrication of future flexible electronic devices on inexpensive and flexible organic substrates requiring a metallization process, the adhesion of metals to polymer substrate is a very critical issue in realizing required flexibility of metallization lines on the flexible substrates. In this work, effect of the surface morphological roughening and surface chemical modification of the PI surface on the adhesion properties of Cu(100 nm)/Cr(50 nm)/PI systems was investigated by varying the substrate bias power at the fixed top power (40 W) and O2 flow rate (300 sccm) in an inductively coupled plasma (ICP) treatment system. The results of contact angle measurements and atomic force microscopy (AFM) showed a large increase in surface roughness under the biased condition resulting in the dramatic decrease of contact angle, ≅ 0° (a complete wetting). Analysis of chemical binding states and surface chemical composition by X-ray photoelectron spectroscopy (XPS) showed an increase in the formation of carbon–oxygen functional groups and the concentration of oxygen on the surface. T-peel test for adhesion strength measurement of Cu/Cr/PI systems showed the peel strength as high as ≅ 126 gf/mm, increased by a factor of 2.2 compared to that of the untreated sample. Observed dramatic increase in the adhesion strengths between PI and Cu/Cr films after plasma treatment at the substrate bias power of 125 W is attributed to a large surface roughness of PI induced by reactive etching in addition to the chemical modification of the plasma-treated PI surface.

Fabrication of a Photoelectronic Device by Direct Chemical Binding of the Photosynthetic Reaction Center Protein to Metal Surfaces

Abstract: 123, 11 512. [14] T. Takenobu, T. Takano, M. Shiraishi, Y. Murakami, M. Ata, H. Kataura, Y. Achiba, Y. Iwasa, Nat. Mater. 2003, 2, 683. [15] S. M. Sze, Physics of Semiconductor Devices, Wiley, New York 1981. [16] C. Klinke, J. Chen, A. Afzali, Ph. Avouris, Nano Lett. 2005, 3, 555. [17] S. Auvray, V. Derycke, M. Goffman, A. Filoramo, O. Jost, J. P. Bourgoin, Nano Lett. 2005, 3, 451. [18] S. Kazaoui, Y. Guo, W. Zhu, Y. Kim, N. Minami, Synth. Met. 2003, 135, 753. [19] J. Lu, S. Nagase, D. P. Yu, H. Q. Ye, R. S. Han, Z. X. Gao, S. Zhang, L. M. Peng, Phys. Rev. Lett. 2004, 93, 116 804. [20] H. Kataura, Y. Maniwa, M. Abe, A. Fujiwara, T. Kodama, K. Kikuchi, H. Imahori, Y. Misaki, S. Suzuki, Y. Achiba, Appl. Phys. A 2002, 74, 349. [21] M. Shiraishi, T. Takenobu, A. Yamada, M. Ata, H. Kataura, Chem. Phys. Lett. 2002, 358, 213. [22] K. Bradley, J.-C. P. Gabriel, M. Briman, A. Star, G. Grüner, Phys. Rev. Lett. 2003, 91, 218 301. [23] T. Kanbara, T. Iwasa, K. Tsukagoshi, Y. Aoyagi, Y. Iwasa, Appl. Phys. Lett. 2004, 85, 6404. [24] A. Javey, J. Guo, B. F. Damon, Q. Wang, D. Wang, R. G. Gordon, M. Lundstrom, H. J. Dai, Nano Lett. 2004, 4, 447. [25] F. Léonard, J. Tersoff, Phys. Rev. Lett. 2000, 84, 4693. [26] A. Zangwill, Physics at Surfaces, Cambridge University Press, Cambridge, UK 1988. [27] S. Kobayashi, T. Nishikawa, T. Takenobu, S. Mori, T. Shimoda, T. Mitani, H. Shimotani, N. Yoshimoto, S. Ogawa, Y. Iwasa, Nat. Mater. 2004, 3, 317.

Characterization and process effects of HfO2 thin films grown by metal-organic molecular beam epitaxy

Abstract: HfO2 dielectric layers were grown on the p-type Si(1 0 0) substrate by metal-organic molecular beam epitaxy (MOMBE). Hafnium-tetrabutoxide [Hf(O·t-C4H9)4] was used as a Hf precursor and argon gas was used as a carrier gas. The microstructure and thickness of HfO2 films were measured by scanning electron microscopy (SEM) and high-resolution transmission electron microscopy (HRTEM). The electrical characteristics of the HfO2 layers were evaluated by high frequency (HF) capacitance–voltage (C–V) and current–voltage (I–V) measurements. The surface morphology, crystal structure, and chemical binding states of HfO2 films were also examined by atomic force microscopy (AFM), X-ray diffraction (XRD), and X-ray photoelectron spectroscopy (XPS) measurements. HF C–V and I–V measurements have shown that HfO2 layer grown by MOMBE has higher dielectric constant (k) of 20–22 and lower leakage current density of ∼10 −8 A/cm 2 compared with the conventional SiO2. In addition, it has been shown that the HfO2 layer has fixed oxide charge of about 8 × 10 11 cm −2 and interfacial state density of about 1 × 10 12 eV −1 cm −2 . The electrical characteristics and surface morphology of HfO2 films are affected by O 2/Ar gas flow ratio. Finally, post-metallization annealing (PMA) was carried out to reduce the interface state density. © 2005 Elsevier B.V. All rights reserved.

Doubly-linked 1D coordination polymers derived from 2 ∶ 2 metallamacrocyclic Ni(II) complexes with bipodal acylthiourea and exo-bidentate N-donor bridging ligands: toward potentially selective chemical sensors?

Abstract: The square planar 2 ∶ 2 metallamacrocyclic Ni(II) complex of 3,3,3′,3′-tetraethyl-1,1′-isophthaloylbis(thiourea) readily forms coordination polymers by axial coordination of various exo-bidentate N-donor linkers: pyrazine, 4,4′-bipyridine, 1,2-bis(4-pyridyl)ethane and 1,2-di(4-pyridyl)ethylene. Steric constraints, together with coordination limited to the axial directions, result in the self-assembly of double-linked 1D ladder structures. One compound in particular, with the bridging ligand 1,2-di(4-pyridyl)ethylene, is found to exist as a quasi-polymer, realising only one-third of its potential linkages. On exposure to various solvents, this compound appears to undergo complete polymerisation, both rapidly and fully reversibly with an associated colour change, making it a potential chemical sensor.

Plasmon resonance biosensor and method

Abstract: A method of analyzing a sample comprising directing a beam of light to a spot on the surface of a microarray treated with the sample using a digital micromirror device, and observing the SPR spectral shift due to a chemical binding event. The digital micromirror device can be, for example, that used in Digital Light Processing (DLP). Such a device can selectively place a pixel of light onto a microarray such that each spot can be observed at millisecond intervals and the whole microarray can be sequentially scanned over a relatively short period. The SPR spectral shift for each spot can be measured as a function of time, thus producing SPR detection of molecular binding in an array format.

Effect of Cu3Sn coatings on electromigration lifetime improvement of Cu dual-damascene interconnects

Abstract: A 20 nm thick Cu3Sn intermetallic compound overlayer on Cu interconnect surfaces was found to effectively block dominant surface diffusion paths, thus resulting in close to one order of magnitude improvement in electromigration lifetimes. This improvement may be explained on the basis of the terrace-ledge-kink model in which the supply of Cu adatoms by the dissociation of atoms from the kinks on the Cu surface steps is hindered by a stronger chemical binding of Sn atoms to the kink sites. The mode of electromigration failures seem to have changed from surface diffusion-induced void formation at the cathode via corner to interfacial and grain-boundary diffusion-induced void formation in the interconnect line.

Method for producing defect free composite membranes

Abstract: A defect free semipermeable composite membrane having excellent integrity and high water permeability is provided. Said composite membrane comprises an inside support layer to provide sufficient mechanical strength; an outside barrier layer to provide selective separation; and a middle layer to provide both physical adhesion and chemical binding between said support and said barrier layer to bond them together. Three different methods for making said defect free composite membrane are discovered. These methods have been successfully utilized to produce high quality coatings and defect free composite membranes, which are independent of chemical composition and physical structure of said support. In the present invention, ultrasonic sonication is discovered to be effective to speed up the phase inversion process of a membrane casting solution, thus allows produce a composite membrane at a speed much higher than those disclosed in the prior art. Said defect free composite membranes have broad applications, ranging from filtration of fruit juice, wine and milk to biotech down stream processing and purification of drinking water, municipal and industrial wastewater.

Immobilization of cells with nitrilase activity from a thermophilic bacterial strain.

Abstract: Cells of the moderately thermophilic Bacillus sp. UG-5B strain, producing nitrilase (EC3.5.5.1), which converts nitriles directly to the corresponding acid and ammonia, were immobilized using different types of matrices and techniques. A variety of sol-gel silica hybrids were tested for entrapment and adsorption of bacterial cells as well as chemical binding on polysulphone membranes. Activation of the matrix surface with formaldehyde led to an increase in immobilization efficiency and operational stability of the biocatalysts. Among the supports screened, membranes gave the best results for enzyme activity and especially operational stability, with retention of 100% activity after eight reaction cycles.

Nanocoating for improving biocompatibility of medical implants

Abstract: A coating for an implant surface comprising one or more nanoparticles of less than or equal to 500 nanometers and an implant surface capable of receiving the nanoparticles, the implant selected from the group consisting of metal, carbon, graphite, polymer, protein, nucleic acid, microorganisms, hydrogel, liquid, porous and polymer blend particles, and combinations thereof. The coating promotes characteristics on the implant surface such as reducing protein unfolding, preventing inflammatory and fibrotic cell accumulation, reducing the number of such cell attachment sites and preventing other adverse biological reactions. The coating may be applied on any material via physical and/or chemical binding. The coating may further comprise a surfactant and may include a tag, adsorbed, absorbed or incorporated onto the nanoparticle. The coating on an implant surface is used for purposes that may be cosmetic, therapeutic, preventative, reconstructive, monitoring and replacement. The coating may also be used for in vitro purposes.

Leaching of composts from agricultural wastes to prepare nursery potting media

Abstract: The leaching of salt and mineral elements from three composts prepared with residual vegetable crop biomass (melon, pepper or zucchini) and from one limed peat (control) was studied using methacrylate columns and distilled water. After 5 container capacities of effluent, both the electrical conductivity and the concentration of soluble elements in compost leachates decreased substantially and equalled those of peat. Composts reacted differently to the leaching of salt due to differences in the raw waste sources and the composting process and hence, in their physical and chemical characteristics, especially organic matter contents. At the end of the experiment, after pouring 8 container capacities of water, the leaching efficiency of the salts was 84%, 89% and 77% for melon, pepper and zucchini-based composts, respectively. Mineral elements differed in their ability to be removed from the composts; available N (NH4 and NO3), K, Na, Cl, and S were leached readily, whereas P, Ca, and Mg were removed hardly due to chemical binding or adsorption. Leached composts showed a range of physico-chemical and chemical parameters suitable for use as growing media constituents. Finally, special emphasis must be paid to the management of the effluents produced under commercial conditions to avoid environmental pollution. INTRODUCTION During the last two decades much attention has been paid to the reclamation of organic wastes and by-products for horticultural utilization. In this line of research composting is one of the most attractive organic waste management methods due to the further reutilization of the end product -compost(Raviv, 1998; Hauke and Stoppler-Zimmer, 1999) in a number of useful applications such as soil amending, fertilization, or restoration, landfill covering, landscaping, containerized medium, and so forth. In order to reduce the consumption of Sphagnum peat, the use of compost in the formulation of soilless growing media has become widespread in certain areas of commercial horticulture, especially in containerized ornamental plant production (Fitzpatrick et al., 1998; Abad et al., 2001; Raviv et al., 2002). There are composts which show physical and chemical characteristics similar to peat, making them suitable as peat substitutes. Nevertheless, most composts can not be used as such for horticultural purposes due to an excess of salts or nutrients that leads to substrates with high electrical conductivity (Abad et al., 2001; GarciaGomez et al., 2002; Sanchez-Monedero et al., 2004). A high salt concentration constitutes a critical and significant limiting factor, particularly in nursery production, since the early growth stages of the plant are very sensitive to growing media salinity (Marschner, 1995). These poor saline composts can be improved either by leaching with water (Chen et al., 1984; Lohr et al., 1984; Marfa et al., 1998) or by mixing with other non-saline materials (Eklind et al., 1998; Atiyeh et al., 2001). This work investigated the leaching of salt and mineral elements from three composts prepared with the residual biomass of different vegetable crops and from one limed peat used as control. Proc. IS on Soilless Cult. and Hydroponics Ed: M. Urrestarazu Gavilan Acta Hort. 697 ISHS 2005 118 MATERIALS AND METHODS Composts and Peat Three mature composts (C1, C2 and C3) prepared with different agricultural wastes mainly residual vegetable crop biomass removed from the soil at the end of the growing seasonwere studied (composition expressed in % by volume): C1 melon (75 %) + yard trimmings (19 %) + almond husk (6 %) C2 pepper (75 %) + almond husk (15 %) + yard trimmings (10 %) C3 zucchini (70 %) + cucumber (15 %) + pepper (15 %) To mixtures C1 and C2 dilute sulphuric acid and ligno-cellulolytic bacteria were added. These mixtures were composted in a pilot plant (University of Almeria, Spain) using a combined system -Rutgers static pile, with forced aeration and controlled temperature, plus pile turningfor 45 days, and they were then left to mature for another 135 days. Mix C3 was added with urea and one enzyme formulae, and composted under commercial conditions (Ejido Medio Ambiente S.A., Almeria, Spain) using the open windrow system with periodical pile turning. Composting lasted 60 days and at that time the compost was allowed to mature for another 15 days. The three composts reached an acceptable degree of maturity -being the total organic carbon to total nitrogen (C/N) ratio about 17, cation exchange capacity ranging from 34 (C3) to 59 cmolc/kg (C1), and cress germination index greater than 60% of the controland showed total organic matter contents of 67%, 70% and 26% for C1, C2 and C3, respectively. For purposes of comparison, a light and weakly-decomposed Finnish Sphagnum moss peat (P) -H1 to H3 according to the Von Post scalewas included as control. The peat was limed with dolomite to raise pH from 3.50 to 5.57. Compost and Peat Characterization The composts and peat were characterized physically at the beginning of the leaching experiment as well as chemically at both the beginning and the end. The geometric particle-size diameter was calculated following Shirazi and Boersma (1984). Dry bulk density, total pore space, air volume and water volume were determined following UNE-EN 13041 (2001). The water release curve was obtained in accordance with De Boodt et al. (1974). The relative hydraulic conductivity at 1 kPa tension -Kr (1 kPa)was predicted by combining the hydraulic models proposed by Mualem (1976) and Van Genuchten (1980). Both the electrical conductivity (EC) and the available mineral element concentrations were determined in the filtered water suspension 1:5 (v:v) as described in UNE-EN 13038 (2001) and UNE-EN 13652 (2002), respectively. All determinations were replicated three times. Column Preparation and Leaching Methacrylate columns measuring 40 cm in height and 5.3 cm in diameter were filled with 883 ml of each material with a moisture content equivalent to container capacity (CC, determined at 2 kPa). The leaching experiment was performed in triplicate (3 columns per material). Loosely-packed cores were compacted by 10% of their height using a piston. Different volumes of distilled water, determined as multiples of container capacity (xCC), were poured through the materials to complete 8xCC. To collect the greatest volume of leachates, the time elapsed between two successive additions of water was 1 hour approximately. The effluents -leachateswere collected continuously and analysed as such for EC and mineral N, P, K, Ca, Mg, Cl, S, Na, and micronutrients determinations. Available N (NO3 and NH4) was determined by distillation, P, K, Ca, Mg, S, Na, and micronutrients by ICP-AES, and Cl by means of an automatic titrator. A leaching efficiency index (LE, %) was calculated (adapted from Kerr and Hanan, 1985) using the equation:

Effects and fate of inhaled ultrafine particles

Abstract: Concentration of inhaled particulate matter (PM) varies by orders of magnitude from ng/m 3 to mg/m 3 , depending on material, particle size, and proximity to sources. Particle number concentrations, expressed as particles/cm 3 , can also span several orders of magnitude, with ultrafine particles ( 2 μm, impaction) and smaller ultrafine (<5 nm, diffusion) particles; in the respiratory tract overall there is minimal deposition at 0.2 - 0.5 μm (settling and diffusional displacement minimal). While chemical composition does not influence deposition of inhaled particles-assuming no hygroscopicity-disposition of deposited particles is highly dependent on their chemical characteristics. Since PM is a chemically complex mixture, different mechanisms including dissolution, leaching, chemical binding and mechanical transport are involved in particle clearance. For solid poorly soluble particles, classical clearance mechanisms are size dependent and pathways include mucociliary escalator in nasal and tracheobronchial airways to the GI-tract, alveolar macrophage-mediated clearance in the alveolar region to the mucociliary escalator, interstitial translocation and lymphatic uptake to regional lymph nodes. More recently, two additional pathways to extrapulmonary organs have been described, specifically for poorly soluble ultrafine particles: translocation to blood circulation; and transport to ganglia and structures of the CNS along axons of sensory nerves located in nasal and tracheobronchial epithelia. This could provide a plausible mechanism for adverse cardiovascular and CNS health effects.

First passage and cooperativity of queuing kinetics

Abstract: We model the kinetics of ligand-receptor systems, where multiple ligands may bind and unbind to the receptor, either randomly or in a specific order. Equilibrium occupation and first occurrence of complete filling of the receptor are determined and compared. At equilibrium, receptors that bind ligands sequentially are more likely to be saturated than those that bind in random order. Surprisingly however, for low cooperativity, the random process first reaches full occupancy faster than the sequential one. This is true except near a critical binding energy where a "kinetic trap" arises and the random process dramatically slows down when the number of binding sites N > or = 8. These results demonstrate the subtle interplay between cooperativity and sequentiality for a wide class of kinetic phenomena, including chemical binding, nucleation, and assembly line strategies.

Theoretical Study of Chemical Binding of Noble Gas Atom and Transition Metal Complexes: Ng–NiCO, Ng–NiN2, Ng–CoCO (Ng = He–Xe)

Abstract: Ab initio multireference and coupled cluster methods (MR-SDCI(+Q), CASPT2, CCSD(T)) and density functional theory methods (B3LYP, MPWPW91) have been applied to examine geometrical structures and vibrational frequencies of noble gas (Ng) – transition metal compounds, Ng–NiCO, Ng–NiN2, and Ng–CoCO (Ng = He, Ne, Ar, Kr, Xe). It is shown that the respective compounds can have a larger binding energy than a typical van der Waals interaction energy. The binding mechanism is explained by a partial electron transfer from a noble gas atom to the low-lying 4s and 3d vacant orbitals of the transition metal atom. Theoretical calculations show that the binding of noble gas atom results in a large shift of the bending frequency: 361.1 cm−1 (NiCO) to 403.5 cm−1 (Ar–NiCO); 308.5 cm−1 (NiN2) to 354.8 cm−1 (Ar–NiN2); 373.0 cm−1 (CoCO) to 422.6 cm−1 (Ar–CoCO). The corresponding experimental frequencies determined in solid argon are 409.1 cm−1 (NiCO), 357.0 cm−1 (NiN2), and 424.9 cm−1 (CoCO), which are much closer to the corresponding frequency of Ar–NiCO, Ar–NiN2, and Ar–CoCO, respectively.

Dry synthesis of triple cumulative double bonds (C=C=C=N) on Si(111)-7 x 7 surfaces.

Abstract: The interactions of cyanoacetylene and diacetylene with a Si(111)-7 × 7 surface have been studied as model systems to mechanistically understand the chemical binding of unsaturated organic molecule...

State of practice report UK stabilisation/solidification treatment and remediation, part V: long-term performance and environmental impact

Abstract: Treatment techniques such as stabilisation/solidification (S/S) are becoming increasingly important in the waste and contaminated land sectors with increasing awareness of the environmental impact arising from these activities and resulting materials. The application of S/S, for the immobilisation of contaminants by the addition of cement-based additives has been widely practised for many years, and has been generally used successfully, although some contaminants are known to pose problems in treatment (Conner, 1990). However, most of this success is based on results of treatability studies, which are normally conducted over short time periods, typically up to 28 days after treatment. As a result, concerns regarding the long-term effectiveness of the technique have regularly been raised in recent years (Conner, 1990; Borns, 1997; Glasser, 1997; Loxham et al., 1997). These concerns are due to (i) the uncertainties in test methods, (ii) observed deficiencies in the process application, (iii) observed lack of chemical binding in crushed samples of treated waste, suggesting that contaminants could leach out under certain conditions and (iv) uncertainties of performance arising from anticipated behavioural degradation of the material over time.

Chimeric Bacteriophages, Chimeric Phage-Like Particles, and Chimeric Phage Ghost Particles, Methods for Their Production and Use

Abstract: The objective of the present invention is to provide chimeric phage-derived particles, that may be used as safe food grade vehicles to for presenting various factors (e.g. antigens, virulence proteins, receptors, ligands, etc.) for living cells. In addition to at least one normal phage or virus component the particles comprise at least one additional factor that is not encoded by the genetic material of the chimeric particle. Applications for such particles include, but are not limited to, vaccine development, pathogen neutralization, chemical binding and/or neutralization (e.g. toxins), and competitive exclusion. In addition, this technology may be used to extend the retention time of phage particles during phage therapy and/or specifically target a given particle for a biofilm.

In Situ Ellipsometry Analysis on Formation Process of Al2O3-Ta2O5 Films in Ion Beam Sputter Deposition

Abstract: Al 2 O 3 -Ta 2 O 5 thin films are known as highly corrosion-resistant materials for coatings. Here the formation process of Al 2 O 3 -Ta 2 O 5 films was analyzed by in situ ellipsometry during deposition by ion beam sputtering. Composite targets composed of Al 2 O 3 and Ta 2 O 5 plates were used for sputter deposition. During deposition, the formation process of thin films was monitored by a single-wavelength rotating analyzer ellipsometer attached to the sputtering system. The composition, the chemical binding states of constituent elements, and the depth profile of the elements of the films were analyzed by inductively coupled plasma-atomic emission spectroscopy, X-ray photoelectron spectroscopy (XPS), and auger-electron spectroscopy (AES), respectively. Ellipso-metric analysis showed that the thickness of the film increased linearly with time after short induction periods. The refractive index of the films increases with increasing tantalum cationic fraction. The extinction coefficient of the films was larger than those of single Al 2 O 3 and Ta 2 O 5 films. The XPS analysis showed that the preferential deposition of the Ta 2 O 5 component occurred in the induction period and the codeposition of Ta 2 O 5 and Al 2 O 3 in the linear growth stage. The AES analysis showed that the content of constituent elements was homogeneous from the top to the bottom of the films in the linear growth stage.

Combined, granulated composition, useful as fertilizer for grass, comprises a basic calcium or magnesium compound mixed with microorganisms, biocatalysts, metal salts and biopolymers

Abstract: Combined preparation (A), in granulated form, comprises at least one basic compound (I) of calcium and/or magnesium, thoroughly mixed with microorganisms and/or biocatalysts (II) and metal salts (III), then conditioned and stabilized. Combined preparation (A), in granulated form, comprises at least one basic compound (I) of calcium and/or magnesium, preferably dust-fine particles of calcite, vaterite, aragonite, dolomite and/or magnesite, enriched and thoroughly mixed with (a) microorganisms and/or biocatalysts (II) at 0.001-5wt.% and (b) metal salts (III) containing 0.2-2% zinc, copper and/or iron. The mixture is conditioned and stabilized with biopolymers (IV) and/or inorganic, surface-active substances (V) and/or alkaline earth hydroxides, and enriched with nutrients having the appropriate chemical binding form. ACTIVITY : Fertilizer. No biological data given. MECHANISM OF ACTION : None given.

High-carbon steel wire with nickel sub coating

Abstract: A wire (10) for external exposure, i.e. without chemical binding with a polymer or rubber matrix. The wire (10) has a steel core (12), a nickel sub-coating (14) and a zinc or zinc alloy top coating (16) above the nickel sub-coating. The steel core (12) has a carbon content exceeding 0.20 %. The wire is in a work-hardened state by drawing or rolling. The wire (10) has an excellent corrosion resistance and provides an excellent barrier against hydrogen. Preferable uses are wires in off-shore applications.

Important bilateral corneal astigmatism in a case of ocular ochronosis

Abstract: Ochronosis or alkaptonuria is a rare, autosomal recessive metabolic disease where the enzyme homogentisic acid 1,2-dioxygenase is missing. This enzyme is necessary in the oxidation of phenylalanine and tyrosine. As a result of this defect homogentisic acid, which is normally produced during the metabolism of the two amino-acids, cannot be further metabolized and therefore accumulates in the serum. It is massively excreted in the urine and as it is oxidized, the urine turns dark, a feature termed alkaptonuria. Tissue pigmentation called ochronosis is due to the presence and the chemical binding in the connective tissue of oxidized and polymerised products of homogentisic acid. The most important complications of alkaptonuric ochronosis as arthropathy are related to deposition of ochronotic pigment in the affected organs. In ocular ochronosis, the pigment is found in the sclera, conjunctiva, and limbic cornea. Vision is usually not impaired. We report the case of a man aged 73 years, with ochronosis, who developped a marked, late-onset bilateral astigmatism, related to this sclero-limbic ochronotic pigment. The clinical evolution, the result of histological examination and the physiopathology of this astigmatism are discussed.

A theoretical study of the structure of the liquid Ga-diamond (111) interface

Abstract: We present the results of a computer simulation study of the structure of the interface between liquid Ga and the (111) face of diamond, with which we reinterpret the findings from an x-ray reflectivity study of that interface [W. J. Huisman, J. F. Peters, M. J. Zwanenburg, S. A. de Vries, T. E. Derry, D. Abernathy, and J. F. van der Veen, Nature (London) 390, 379 (1997); Surf. Sci. 402–404, 866 (1998)]. That experimental study has been interpreted to show that the contact of Ga with the (111) face of diamond induces the formation of Ga2 molecules for several layers into the bulk liquid, with the axes of the Ga2 molecules in successive layers oriented perpendicular to the diamond surface. No driving force for the proposed formation of Ga2 molecules is identified. The simulations reported in this paper are based on a model that permits chemical binding of Ga, as a dimer, to the CC double bonds in the reconstructed (111) face of diamond, thereby identifying the driving force for dimerization. We show that ...

Incoherent neutron-scattering determination of hydrogen content: Theory and modeling

Abstract: Hydrogen concentrations of 0 up to 350?mg/kg in a titanium alloy have been determined at National Institute of Standards and Technology (NIST) with neutron incoherent scattering (NIS) and with cold neutron prompt gamma activation analysis. The latter is a well-established technique, while the former was demonstrated earlier at NIST by counting the neutrons scattered under 45° or 60° and establishing a linear relationship between hydrogen concentration and count rate. In this paper, it is shown that the NIS response is complicated by the dependence of the apparent hydrogen scattering cross section on the sample temperature and the hydrogen chemical binding. It is demonstrated that detection of scattered neutrons at two different angles as well as a more complex theoretical approach (i.e., including Monte Carlo modeling with the free-gas model) are required to correctly interpret NIS measurements. As a result, the process of matching standards and samples becomes less critical.

Chimeric phage-derived particles, methods for their production and use

Abstract: The objective of the present invention is to provide chimeric phage-derived particles, that may be used as safe food grade vehicles to for presenting various factors (e.g. antigens, virulence proteins, receptors, ligands, etc.)for living cells. In addition to at least one normal phage or virus component the particles comprise at least one additional factor that is not encoded by the genetic material of the chimeric particle. Applications for such particles include, but are not limited to, vaccine development, pathogen neutralization, chemical binding and/or neutralization (e.g. toxins), and competitive exclusion. In addition, this technology may be used to extend the retention time of phage particles during phage therapy and/or specifically target a given particle for a biofilm.

Biodegradable Porous Nano-Hydroxyapatite/Alginate Scaffold

Abstract: Porous scaffold containing biodegradable Ca-crosslinked alginate(ALG) and nano-hydroxyapatite(n-HA) is synthesized by the freeze-extraction and freeze-gelation methods. The prepared scaffolds were tested by scanning electron microscopy (SEM), transmission electron microscopy (TEM), infrared absorption spectra (IR), raman spectra, X-ray diffraction (XRD) and burning test. Chemical binding between inorganic n-HA and Ca-crosslinked alginate was investigated. It indicated that n-HA was interacted with Ca-crosslinked alginate. The results of SEM showed that the scaffolds exhibited open-cellular pore structures. The content of n-HA affected the porosity and pore size of the composite. The composite can be a promising scaffold material for tissue engineering.

Nanocoating for improving biocompatibility of medical implants

Abstract: A coating for an implant surface comprising one or more nanoparticles of less than or equal to 500 nanometers and an implant surface capable of receiving the nanoparticles, the implant selected from the group consisting of metal, carbon, graphite, polymer, protein, nucleic acid, microorganisms, hydrogel, liquid, porous and polymer blend particles, and combinations thereof. The coating promotes characteristics on the implant surface such as reducing protein unfolding, preventing inflammatory and fibrotic cell accumulation, reducing the number of such cell attachment sites and preventing other adverse biological reactions. The coating may be applied on any material via physical and/or chemical binding. The coating may further comprise a surfactant and may include a tag, adsorbed, absorbed or incorporated onto the nanoparticle. The coating on an implant surface is used for purposes that may be cosmetic, therapeutic, preventative, reconstructive, monitoring and replacement. The coating may also be used for in vitro purposes.

Optical multilayer film element

Abstract: PROBLEM TO BE SOLVED: To provide an optical multilayer film combined element having an excellent optical characteristic SOLUTION: The optical multilayer film element of the present invention is provided with: a first multilayer film formed by laminating materials having different refraction indices, and having a SiO 2 layer at least on one face; and a second multilayer film formed by laminating materials having different refraction indices and having a SiO 2 layer at least on one face The SiO 2 layers of the first and the second multilayer films are bonded together with a chemical binding reacted by using a chemical including hydrofluoric acid COPYRIGHT: (C)2006,JPO&NCIPI