Purpose - This paper aims to describe the technology and applications of nanocompositematerials. Design/methodology/approach - This paper discusses products, applications and technological developments in polymer, ceramic and metal nanocomposites. It concludes with a brief consideration of electronic component applications. Findings - It is shown that polymer nanocomposites and the materials used in their production are commercially available and finding applications in several industries, including automotive, military, food, electronics and leisure, due to their enhanced mechanical, electrical and thermal properties. Ceramic and metallic nanocomposites are at an earlier stage of development and a critical issue to resolve is optimising the dispersion of nanomaterials in the matrices. Pa...
There has been considerable interest in producing and studying nanoparticle materials because of the effect of size on their structure, physical and chemical structure. Most studied nanoparticle semiconductors belong to the II-VI group, as they are relatively easy to synthesize and are generally prepared as particulates or in thin film form. Among II-VI compounds, CdS is one of the most studied materials. There are different ways to synthesize CdS nanoparticles such as colloidal particles, chemical decomposition, sol-gel, gas evaporation, magnetron sputtering, electrostatic deposition, and etc. {gamma}-irradiation is one of the effective methods for synthesis of nanomaterials. These nonomaterials have been extensively used in the preparation of nanocrystalline metals, metal oxides, and metal-polymer composites. However, The preparation of CdS nanoparticle and CdS/ polyacrylonitrile ...
Abstract:- In recent years, the study of polymer/clay nanocomposites has attracted major research and commercial interests due to their superior mechanical and thermal properties to those of the neat polymers. Numerical modelling is an advantageous approach to understand the material behaviour. In this work a symmetric two dimensional finite element model is developed to simulate the fully exfoliated Polymer/Clay nanocomposite behaviour and evaluate its- before stress stress-strain curve. The Nylon 66/Clay in this study has a nonlinear elastic behaviour. The influence of volume fraction and aspect ratio of clay platelet (defined as the ratio of the particle length to the particle thickness) on the tensile behaviour of exfoliated Nylon 66/clay nanocomposite is investigated with the aid of n...
Nanocomposites comprising nanocrystal silicon (Si), disordered carbon (DC), and multi-walled carbon nanotubes (MWCNTs) - denoted as Si/DC/MWCNTs - have been prepared by pyrolyzing the phenol-formaldehyde resin (PFR) mixed with Si and MWCNTs. This nanocomposite anode material showed a discharge capacity of 1216 mAh/g in the first cycle, and a charge capacity of 711 mAh/g after 20 charge-discharge, much higher than that of Si/DC composite. It can be observed that Si particles wrapped in MWCNTs were homogeneously embedded into the matrix of the DC. The improved electrochemical performance is hypothesized to be mainly attributed to the morphology stability of the composite due to the excellent resiliency and distinct electric conductivity of the MWCNTs.
Abstract Nanocomposites based on SnO2 with carbon scaffold were used as highly porous anode films on Ni substrates. The films were obtained by in situ deposition of the particles without any binder or excess carbon black avoiding any secondary treatment. Compared to similarly prepared uncoated SnO2 nanoparticles as well as conventionally prepared powder samples the capacity loss of the in situ deposited nanocomposite films is significantly reduced. Thus, this newly developed anode material combined with in situ film formation is a promising approach for high capacity anodes in Li-ion batteries. SEM-micrograph of a SnO2/C nanoparticle film.
Structure and magnetic properties of the thermal decomposition products of Fe(III(Co(II) acrylate complex were analysed. The crystalline phases, which were found in the fully processed material, at 643 K, were Fe_3O_4, CoFe_2O_4 and CoO and had a mean particle size of about 30 nm. In the intermediate stages of the thermolysis iron was present in a form of Fe"I"I"I (trivalent low-spin iron), Fe"2"+ (divalent high-spin iron), and Fe_3O_4. The coercivity and remanence were measured versus temperature in the range of 5-300 K, in 1.1 T applied field. Both _MH_c and M_r, decreased showing room temperature values of 0.038 T and 7.49 mT, for coercivity and remanence, respectively. At temperatures below 200 K the hysteresis loops were asymmetrical, opened and shifted towards negative field values. (author)
Alumina-reinforced carbon nanofiber nanocomposites were prepared using different routes; powders mixture, colloidal route and sol?gel process followed by spark plasma sintering (SPS). CNFs/xAl2O3 (x = 10?50 vol.%) were prepared through nanopowders mixing in a high-energy attrition milling. The main limitations in the preparation of this kind of nanocomposites are related to the difficulty in obtaining materials with a homogeneous distribution of both phases and the different chemical nature of CNFs and Al2O3, which causes poor interaction between them. A surface coating of CNFs by wet chemical routes with an alumina precursor is proposed as a very effective way to improve the interaction between CNFs and Al2O3. An improvement of 50% in fracture strength was found for similar nanocomposite ...
Abstract A one step method was used to prepare stable aqueous nanocomposite dispersions based on cellulose whiskers extracted from the rachis of the date palm tree and a poly(styrene co 2 ethyl hexylacrylate) copolymer via miniemulsion polymerization. A reactive silane, i.e., methacryloxypropyl triethoxysilane was added to stabilize the dispersion and favor the anchoring of the whiskers on polymer particles. Dynamic light scattering was used to study the effect of the silane and whiskers contents on the average particle size of the polymer. Nanocompositesmaterials were prepared from these dispersions using a casting/evaporation method. The effect of the silane and whiskers contents on the thermal and mechanical properties were studied using differential scanning calorimetry and dynamic me...
DescriptionThe objective is to exploit the use of wheat as an industrial raw material and understand the effect of material variation in wheat starch and flour on final material properties for food packaging applications. The project will focus on property enhancement in terms of stiffness, strength, toughness, moisture barrier resistance, transparency, ageing resistance, microbial stability and biodegradability of starch-based packaging materials made by sheet extrusion and thermoforming processes, in ord [continued...
A type of Si3N4-based nanocomposites ceramic cutting tool material was prepared by the addition of nano-scale Si3N4W whisker and nano-scale TiN particle. Cutting performance of the Si3N4/Si3N4W/TiN nanocomposite ceramic tool in machining of cast iron was investigated in comparison with a commercial sialon ceramic tool, and the tool wear mechanism was studied. The two types of cutting tools have similar cutting performance at relatively low cutting parameters, while Si3N4/Si3N4W/TiN nanocomposite tool exhibits a better wear resistance than sialon tool at the relatively high cutting parameters. The wear of sialon ceramic cutting tool is dominated by the plastic deformation, abrasive action, microcracking, pullout of grains and chemical action at the higher cutting parameters. The higher mech...
Some results and experimental procedures of laboratory are reported in the frame of researches conducted for the development of new nanostructured composite materials. These new materials, which are constituted by an organic phase: the polymer and an inorganic phase: the silicate, are being strongly investigated nowadays so it is expected that they could provide, among other, better electrical insulation properties and flame-delay in electrical and electronic applications. The laboratory experimental work has been developed from two families of polymers, thermoplastics and thermosets and clays silicates providing lamellar type. There are now some preliminary results, such as obtaining thin films of these nanocompositematerials, their complete characterization by X-ray diffraction, scanning microscopy and thermogravimetric analysis, they do well to wait for future research activities. (author)
... centers in materials research. MRSECs address fundamental materials research topics of intellectual ... in materials research. II. PROGRAM DESCRIPTION MRSECs are supported by NSF to undertake materials ...
In-situ sodium activated organo modified bentonite clay was also used for partial replacement of the carbon black (N330). Detailed study with the black filled compound revealed that, with slight modification of the curing package, up to 10 phr of the carbon black replacement is possible. At equivalent loading of 5 and 10 phr of in-situ sodium activated organo modified bentonite clay exhibited better properties in comparison to carbon black filled compound.
Thin films (1-10 ?m thickness) of nanocomposites (NC) based on organic coordinated compound (OCC) Eu(TTA)2(Ph3PO)2NO3 (where TTA is thenoyl trifluoroacetonate (C8H5F3O2S), Ph3PO - triphenylphosphine (C6H5PO) and polymer-polyvinylpyrrolidone ((C6H9NO)n) (PVP)) were obtained by chemical methods and with different molar ratios into organic polymer matrix. NC have been characterized by measurements of optical transmission, excitation spectra of photoluminescence (PL) and photoluminescence of NC at different concentrations of Eu(TTA)2(Ph3PO)2NO3 in NC. In the optical transmission of NC, the characteristic parameters of NC such as threshold absorbance, dependence on the concentration of the organic coordinated compound in NC, etc., have been determined The displacement of threshold absorption to infrared is observed with increasing of the concentration of the coordination material in NC. The excitation spectrum of photoluminescence of NC led the ...
TEM and HRTEM have been used to characterise the microstructures of materials formed by hot-pressing silicon nitride with an Al_2O_3-SiO_2-TiO_2 densification aid system, to form #beta#'-sialon-TiN composites in which the TiN particles are of 20-100 nm dimension. (orig.).
Four species of nanocomposites organized by hydroxyapatite (HAp), hyaluronic acid (HyA), chondroitin sulfate (ChS) and type II collagen (Col), i.e. HAp/HyA, HAp/ChS, HAp/HyA/Col and HAp/ChS/Col composites, were synthesized by coprecipitation methods. The composites could retain lots of water: 40%, 32%, 42% and 58% for the HAp/HyA, HAp/ChS, HAp/HyA/Col and HAp/ChS/Col composites, respectively. Transmission electron microscopy observations revealed that the HAp/HyA and HAp/ChS composites consisted of island-like aggregations whose sizes were 300 nm in length and 30 nm in width, and 150 nm in length and 30 nm in width, respectively. In the aggregations, there were many HAp nanocrystals of 20 nm in length, and their c-axes were aligned along the respective polymer molecules through a self-organization process. Animal tests showed that chondrocyte-like cells penetrated into the HAp/ChS/Col composites 4 weeks after implantation. It was shown that the ...
In this article, several applications of nanomaterials in food packaging and food safety are reviewed, including: polymer/clay nanocomposites as high barrier packaging materials, silver nanoparticles as potent antimicrobial agents, and nanosensors and nanomaterial-based assays for the detection of food-relevant analytes (gasses, small organic molecules and food-borne pathogens). In addition to covering the technical aspects of these topics, the current commercial status and understanding of health implications of these technologies are also discussed. These applications were chosen because they do not involve direct addition of nanoparticles to consumed foods, and thus are more likely to be marketed to the public in the short term.
Chemical looping combustion (CLC) is an emerging technology for clean combustion. We have previously demonstrated that the embedding of metal nanoparticles into a nanostructured ceramic matrix can result in unusually active and sinter-resistant nanocomposite oxygen carrier materials for CLC which maintain high reactivity and high-temperature stability even when sulfur contaminated fuels are used in CLC. Here, we propose a novel process scheme for in situ desulfurization of syngas with simultaneous CO{sub 2}-capture in chemical looping combustion by using these robust nanocomposite oxygen carriers simultaneously as sulfur-capture materials. We found that a nanocomposite Cu-BHA carrier can indeed strongly reduce the H{sub 2}S concentration in the fuel reactor effluent. However, during the process the support matrix is also sulfidized and takes part in the redox process of CLC. This ...
Abstract in english Structural characterisations using the SAXS technique in a number of nanoheterogeneous materials and liquid solutions are reviewed. The studied systems are protein (lysozyme)/water solutions, colloidal ZnO particles/water sols, nanoporous NiO-based xerogels, hybrid organic-inorganic siloxane-PEG and PPG nanocomposites and PbTe semiconductor nanocrystals embedded in a glass matrix. These investigations also focus on the transformations of time-varying structures and on str (more) uctural changes related to variations in temperature and composition. The reviewed investigations aim at explaining the unusual and often interesting properties of nanostructured materials and solutions. Most of the reported studies were carried out using the SAXS beamline at the National Synchrotron Light Laboratory (LNLS), Campinas, Brazil.
Homogeneous mixtures of Ce0.8Gd0.2O1.9 (GDC) and La0.6Sr0.4Co0.2Fe0.8O3 (LSCF) nanopowders were successfully synthesized using induction plasma by axial injection of a solution. The resulting nanocomposite powders consisted of two kinds of nanopowders with different mass ratio of GDC/LSCF, such as 3/7 and 6/4. The morphological features, crystallinity, and the phases of the synthesized powders were characterized by scanning electron microscopy (SEM), transmission electron microscopy (TEM), local energy-dispersive x-ray spectroscopy (EDS) analysis, and x-ray diffraction (XRD). The nanopowders are almost globular in shape with a diameter smaller than 100?nm and their BET specific areas are around 20?m2?g?1. The GDC and LSCF phases are well distributed in the nanopowders. In addition, suspens...
We synthesized Fe3O4Gg nanocomposites through a combination of solvothermal, hydrothermal, and chemical redox reactions. Characterization of the resulting samples by X-ray diffraction, Fourier-transform infrared spectroscopy, field-emission scanning and transmission electron microscopy, and magnetic measurement is reported. Compared to Fe3O4g nanocomposites, the Fe3O4Gg nanocomposites showed enhanced antibacterial activity. The Fe3O4Gg nanocomposites were able to almost entirely prevent growth of Escherichia coli when the concentration of Ag nanoparticles was 10mg/mL. Antibacterial activity of the Fe3O4Gg nanocomposites was maintained for more than 40h at 37^oC. The intermediate carbon layer not only protects magnetic core, but also improves the dispersion and antibacterial activity of the...
Medium-density polyethylene/multiwall carbon nanotube (MDPE/MWCNT) nanocomposites were produced by a mechanical milling method using a high-energy ball mill. The MDPE and MWCNTs were added to the ball mill at a constant 20:1 weight ratio of ball/powders and milled for 10 h to obtain polyethylene matrix nanocomposites reinforced with 0.5, 1, 2.5, and 5 weight percent of MWCNTs. To clarify the role of both MWCNT content and milling time on the morphology of MDPE, some nanocomposite samples were investigated by using a scanning electron microscope. To evaluate the role of milling on the microstructure of the nanocomposites, very thin films of MDPE/MWCNTs were prepared and studied by transmission electron microscopy. Thermal behavior of these nanocomposites was investigated by using differenti...
Porous phosphate heterostructures (PPH), functionalized with different ratios of aminopropyl and mercaptopropyl groups, labelled as Nx=5,25,50-PPH and Sx=5,25,50-PPH, respectively, were tested as adsorbents for Ni(II) and Hg(II) found in industrial sewage from electroplating processes and button battery recycling. X-ray diffraction was used to study the structures. The specific surface area of the pristine material (PPH) was 620m^2g^-^1, whereas the specific surface areas of the modified mercaptopropyl (S5-PPH) and aminopropyl (N5-PPH) were 472 and 223m^2g^-^1, respectively. The adsorption data were fitted to a Langmuir isotherm model. The S5-PPH material was saturated by 120mmol Hg(II) per 100g of material, whereas for Ni(II) adsorption, N25-PPH material displayed the highest adsorption w...
A novel method for the determination of metoclopramide (MCP) using electrogenerated chemiluminescence (ECL) is presented. A tris(2,2prime-bipyridyl)dichlororuthenium(II) (Ru(bpy)32+)-doped silica (RuDS) nanoparticle/perfluoinated ion-exchange resin (Nafion) with nanocomposite membrane modified glassy carbon electrode (GCE) is used. The Ru(bpy)32+ encapsulation interior of the silica nanoparticle maintains its electrochemical activities and also reduces Ru(bpy)32+ leaching from the silica matrix when immersed in water due to the electrostatic interaction. The analytical performance of this ECL sensor for MCP is shown in detail. Under optimal experimental conditions, it has good linearity in the concentration range from 2x10-8mol/L to 1x10-5mol/L (R=0.9989) with a detection limit of 7x10-9mo...
These three volumes cover liposome technology in pharmacology and medicine. Contributors emphasize methodology used in their own laboratories, and include a brief introduction, coverage of relevant literature, applications and critical evaluations for the methods they describe. Volume II presents procedures for the entrapment of a number of drugs, including genetic material, into selected types of liposomes.
High-temperature LiCl-KCl molten salt medium provides an efficient way to produce the paramagnetic Eu(II) ion to be magnetically diluted into a diamagnetic host medium. Eu(II) was formed by a dissolution and an auto-reduction processes in a high-temperature LiCl-KCl eutectic melt at 723 K by using Eu{sub 2}O{sub 3} as a starting material. By using EPR and luminescence spectroscopic method, we studied the nature of the magnetically isolated paramagnetic Eu(II) ion diluted in a LiCl-KCl medium. With the aid of these spectroscopic tools, it was found that stable Eu(II) species was formed spontaneously at 723 K under anaerobic conditions. EPR and luminescence spectroscopy provided detailed information regarding the nature of the europium ion in a molten salt.
High-temperature LiCl-KCl molten salt medium provides an efficient way to produce the paramagnetic Eu(II) ion to be magnetically diluted into a diamagnetic host medium. Eu(II) was formed by a dissolution and an auto-reduction processes in a high-temperature LiCl-KCl eutectic melt at 723 K by using Eu_2O_3 as a starting material. By using EPR and luminescence spectroscopic method, we studied the nature of the magnetically isolated paramagnetic Eu(II) ion diluted in a LiCl-KCl medium. With the aid of these spectroscopic tools, it was found that stable Eu(II) species was formed spontaneously at 723 K under anaerobic conditions. EPR and luminescence spectroscopy provided detailed information regarding the nature of the europium ion in a molten salt.
High-temperature LiCl-KCl molten salt medium provides an efficient way to produce the paramagnetic Eu(II) ion to be magnetically diluted into a diamagnetic host medium. Eu(II) was formed by a dissolution and an auto-reduction processes in a high-temperature LiCl-KCl eutectic melt at 723K by using Eu2O3 as a starting material. By using EPR and luminescence spectroscopic method, we studied the nature of the magnetically isolated paramagnetic Eu(II) ion diluted in a LiCl-KCl medium. With the aid of these spectroscopic tools, it was found that stable Eu(II) species was formed spontaneously at 723K under anaerobic conditions. EPR and luminescence spectroscopy provided detailed information regarding the nature of the europium ion in a molten salt.
There has been a growing interest in new laser systems for use at mid-infra-red wavelengths, driven by requirements for a number of diverse applications. Developments in mid-IR coating technology are following three major thrusts. In the first, the potential of ion-assisted process is being exploited and the technology is already becoming well established in the optical coating industry. In the second, the benefits of using gas-phase precursors are being explored, driven by the potential of avoiding the generation of second phase inclusion in the coatings with associated reduction in laser damage threshold. Research is also addressing the use of nanocompositematerials with an engineered microstructure to produce coatings with dielectric properties of choice. This paper presents a review of progress in some of these areas with special emphasis on the comparison of the properties of materials at DF laser wavelengths. ...
The sol-gel-immobilized Tris(2,2'-bipyridyl)ruthenium(II) [Ru(bpy)_3 "2"+] electrogenerated chemiluminescence (ECL) sensor was applied to the reversed-phase high-performance liquid chromatography (HPLC) determination of phenothiazine derivatives (promazine, chlorpromazine, triflupromazine, thioridazine, and trifluoperazine) and erythromycin in human urine samples. In this method, Ru(bpy)_3 "2"+ was immobilized in sol-gel-derived titania (TiO_2)-Nafion nanocomposite films coated on a dual platinum electrode. This method eliminates an extra pump needed for the delivery of Ru(bpy)_3 "2"+ reagent into a reaction/observation zone in front of photomultiplier tube because the immobilized-Ru(bpy)_3 "2"+ is recycled on the electrode surface by an applied potential at +1.3 V versus Ag/AgCl (3 M NaCl) reference electrode. The resulting analytical performances such as detection limit, working range, sensitivity, and measurement precision were slightly ...
The sol-gel-immobilized Tris(2,2'-bipyridyl)ruthenium(II) [Ru(bpy){sub 3} {sup 2+}] electrogenerated chemiluminescence (ECL) sensor was applied to the reversed-phase high-performance liquid chromatography (HPLC) determination of phenothiazine derivatives (promazine, chlorpromazine, triflupromazine, thioridazine, and trifluoperazine) and erythromycin in human urine samples. In this method, Ru(bpy){sub 3} {sup 2+} was immobilized in sol-gel-derived titania (TiO{sub 2})-Nafion nanocomposite films coated on a dual platinum electrode. This method eliminates an extra pump needed for the delivery of Ru(bpy){sub 3} {sup 2+} reagent into a reaction/observation zone in front of photomultiplier tube because the immobilized-Ru(bpy){sub 3} {sup 2+} is recycled on the electrode surface by an applied potential at +1.3 V versus Ag/AgCl (3 M NaCl) reference electrode. The resulting analytical performances such as detection limit, working range, ...
Nanocomposites containing polyethylene (PE) and montmorillonite clay organically modified (OMMT) with quaternary ammonium salts were obtained via direct melt intercalation. A montmorillonite sample from the Brazilian state of Paraiba was treated with four different types of quaternary ammonium salts. After the treatment, the powder was characterized by X-ray diffraction and scanning electron microscopy. The dispersion and morphologies of OMMT within PE were investigated by X-ray diffraction and transmission electron microscopy. The results revealed the formation of intercalated montmorillonite layers in the PE matrix. The thermal stability and flammability of the PE/montmorillonite clay nanocomposites were measured by thermogravimetry and horizontal burning tests for HB classification, Underwrites Laboratories (UL 94), respectively. It was shown that the samples do not degrade at the processing temperature. By adding only 3 wt.% ...
Theoretically, the outcome of World War II in Europe hung in the balance as the Allies poured onto the Normandy beachhead. Following the June 6, 1944 invasion, the Allies continue to come ashore, massively building up men and material inside the beachhead...
The major activities of the various Institute's departments are highlighted. The following departments are included: (i) Tokamak; (ii) Pulse plasma systems; (iii) Thermal plasma; (iv) Materials engineering; (v) Laser plasma; and (vi) Optical diagnosis. (P.A.)
This book contains over 20 selections. Some of the titles are: Continuum damage mechanics studies on the dynamic fracture of concrete; Dynamic compressive strength of cementitious materials; Rate-sensitivity of mode I and mode II fracture concrete; and An impact damage model of concrete.
The repulsive Casimir force is expected as a force which enables to levitate small objects such as machine parts used in Micro Electro Mechanical Systems (MEMS), and superlubricity in MEMS may be realized by this levitation. We study the Casimir force between a gold sphere and a nanocomposite sheet containing many nickel nanoparticles. In particular, we focus on the dependence of the Casimir force on the separation between the gold sphere and the surface of the nanocomposite sheet. The Casimir force changes from the attractive force to the repulsive force as the separation increases. The strength of the repulsive force is, however, too small to levitate MEMS parts.
In this note it is suggested that binuclear platinum(II) complexes with a solely inorganic bridging pyrophosphito ligand also possess many of the complementary advantages of inorganic and organic dyes. They are evaluated for their potential use as a luminescent solar concentrator material. The disadvantages include: the high cost of platinum; the absorption spectra in solution shows a weaker absorption at 452 nm which may cause reabsorption of emitted light; the positions of the absorption and emission maxima are not at the optimal wavelengths for absorption of sunlight and emission to a solar cell. In spite of these drawbacks the author believes the platinum complexes merit consideration for fabrication of solar concentrator devices.
Individual nanoscale building blocks exhibit a wide range of size-dependent properties, since their size can be tuned over known characteristic length scales of bulk materials. In the last several years, the possibility of combining different materials in the form of two and three component nanoparticles (NPs) has been extensively explored. Also multi-component materials can be obtained via self-assembly of NPs from their binary colloidal mixtures. These new nanocrystal solids may possess tunable collective properties that originate from interactions between size and composition controlled building blocks. Exchange coupling between neighboring NPs of magnetically soft and hard materials enhances the magnetic energy product of the nanocompositematerial. Randomly mixed solids of small and large semiconducting CdSe NPs revealed enhancement of photoluminescence ...
Novel fluoroalkyl end-capped vinyltrimethoxysilane oligomer/hydroxyapatite (HAp) nanocomposites were prepared by the reaction of calcium nitrate tetrahydrate and phosphoric acid in the presence of the corresponding oligomer. These fluorinated oligomer/HAp composites thus obtained are nanometer size-controlled fine particles (83-173 nm), and were found to exhibit good dispersibility in methanol, ethanol, and isopropyl alcohol. These fluorinated HAp nanocomposites were applied to the surface modification of glass and poly(methyl methacrylate) (PMMA) to exhibit good hydro- and oleophobic characteristics imparted by fluorine on their surface. In addition, the surface structural changes of the modified polyethylene terephtalate and PMMA films treated with these fluorinated nanocomposites before...
Cellulose whiskers and microfibrillated cellulose (MFC) were extracted from the rachis of date palm tree and characterized. These cellulosic nanoparticles were used as reinforcing phase to prepare nanocomposite films using latex of natural rubber as matrix. These films were obtained by the casting/evaporation method. The properties of the ensuing nanocomposite films were investigated using differential scanning calorimetry, toluene and water uptake experiments, dynamic mechanical analysis and tensile tests. The stiffness of the natural rubber was significantly increased above its glass-rubber transition temperature upon nanoparticles addition. The reinforcing effect was shown to be higher for nanocomposites with MFC compared to whiskers. It was ascribed to the higher aspect ratio and possi...
Ruthenium(II) and Iridium(III) polypyridyl complexes have been intensively investigated due to their use in energy conversion and light-emitting devices and materials for non-linear optics. Quantum mechanical computer simulations of molecules and materials have become increasingly popular in the scientific community. Along with experimental investigations, such computational analyses can provide complementary information on the electronic and optical properties of transition metal compounds of interest for optoelectronic applications. Here, we provide a unified review of recent work carried out on computational investigations of a large series of Ruthenium(II) and Iridium(III) polypyridyl complexes, discussing the relations between their electronic structure and optical properties and thei...
Abstract A diacrylate polysulfone oligomer is synthesized and used as the acrylic oligomer for the in situ synthesis of noble metal/PSU nanocomposites through UV-induced simultaneous radical polymerization of acrylic functionalities and NP formation by reduction of their precursors. Thus, silver or gold NPs are formed in situ during polymer network formation. FESEM analysis of the morphology of the cured systems demonstrates that the nanoparticles of the noble metals are homogeneously distributed in the network without macroscopic agglomeration.
Ordered mesoporous C-TiO2 nanocomposites with crystalline framework were prepared by the evaporation-induced triconstituent co-assembly method. The products were characterized by XRD, TEM, N2 adsorption-desorption and TG. Their microwave absorption properties were investigated by mixing the product and epoxy resin. It is found that the peak with minimum reflection loss value moves to lower frequencies and the ordered mesoporous C-TiO2 nanocomposite possesses an excellent microwave absorbing property with the maximum reflection loss of -25.4 dB and the bandwidth lower than -10 dB is 6.6 GHz. The attenuation of microwave can be attributed to dielectric loss and their absorption mechanism is discussed in detail. The mesoporous C-TiO2 nanocomposites also exhibit a lower infrared emissivity in the wavelength from 8 to 14 ?m than that of TiO2-free powder. -- Graphical abstract: Ordered mesoporous C-TiO2 ...
Effect of radiation dose and carbon nanotubes (CNT) on the mechanical properties of standard Malaysian rubber (SMR) was investigated in this study. SMR nanocomposites containing 1-7 phr CNT were prepared using the solvent casting method and the nanocomposites were radiated at doses of 50-200 kGy. The change in mechanical properties, especially, tensile strength (Ts), elongation at break (Eb), hardness and tensile modulus at 100% elongation (M{sub 100}) were studied as a function of radiation dose. The structure and morphology of reinforced natural rubber was investigated by FESEM, TEM and AFM in order to gain further evidence on the radiation-induced crosslinking. It was found that the Ts, M{sub 100} and the hardness of the SMR/CNT nanocomposites significantly increased with radiation dose; the elongation at break exhibited an increase up to 100 kGy, and a downward trend thereafter. Results on gel fraction further confirmed ...
One of the key features of ANL's Integral Fast Reactor (IFR) concept is a close-coupled fuel cycle. The proposed fuel cycle is similar to that demonstrated over the first five to six years of operation of EBR-II, when a fuel cycle facility adjacent to EBR-II was operated to reprocess and refabricate rapidly fuel discharged from the EBR-II. Locating the IFR and its fuel cycle facility on the same site makes the IFR a self-contained system. Because the reactor fuel and the uranium blanket are metals, pyrometallurgical processes (shortned to ''pyroprocesses'') have been chosen. The objectives of the IFR processes for the reactor fuel and blanket materials are to (1) recover fissionable materials in high yield; (2) remove fission products adequately from the reactor fuel, e.g., a decontamination factor of 10 to 100; and (3) upgrade the ...
Fluoroalkyl end-capped vinyltrimethoxysilane oligomer suffered the sol-gel reaction under alkaline conditions in the presence of titanium oxide nanoparticles in tetrahydrofuran to afford the corresponding fluorinated oligomer/titanium oxide nanocomposites[RF-(VM-SiO2)n-RF/TiO2] in excellent to moderate isolated yields. These fluorinated composites thus obtained were nanometer size-controlled fine particles, and exhibited good dispersibility and stability in traditional organic solvents except for water. These fluorinated nanocomposites were applied to the surface modification of glass to exhibit not only a completely superhydrophobic characteristic (a water contact angle: 180degree) with a non-wetting property against water droplets but also a good oleophobicity imparted by fluoroalkyl seg...
This paper presents a detailed characterization and rheometric property study of in-situ sodium activated, organomodified bentonite clay - styrene-butadiene rubber (SBR) nanocomposite. It was found that around 10phr loading was the optimum level for maximum effect of the organo clay. The WAXD data indicated that at higher loading there was formation of agglomerations in the matrix. It was found that organo clay compound exhibited lower maximum torque in comparison to equivalent amount of carbon black loaded compound. The nanocomposites were also used for partial replacement of N330 carbon black in a highly black loaded compound. Part replacement of the carbon black with nano-clay reduced the maximum rheometric torque in comparison to the control compound. Detail study revealed that with sl...
Here, a general approach for the preparation of reduced graphite oxide (rGO)-silver nanocomposite has been investigated. Graphite oxide (GO) sheets are used as the nanoscale substrates for the formation of rGO-silver composite. GO sheets and Ag ions can be reduced at the same time, under a mild condition using l-ascorbic acid (l-AA) as reducing agent. This simple approach should find practical applications in the production of rGO-silver nanocomposite. The SEM analysis indicates that the silver particles are dispersed on graphene sheets. Raman signals of rGO in the composite are increased by the attached silver nanoparticles, displaying surface-enhanced Raman scattering activity. The degree of enhancement can be adjusted by varying the quantity of silver nanoparticles in the composite. In ...
Ni-Co/SiC nanocomposite coatings were electrodeposited in a modified watt type of Ni-Co bath containing 20nm SiC particles to be codeposited. Potentiodynamic polarization tests were conducted to study the effect of the SiC particulates on the electrodeposition of Ni and Co. Scanning electron microscopy was used to assess the morphology of the Ni-Co alloy and Ni-Co/SiC nanocomposite coatings. The distribution of the particulates in the matrix was considered by means of transmission electron microscopy. Applying nanomechanical testing instruments coupled to atomic force microscopy, mechanical properties of the alloy and composite coatings were studied and compared. The presence of 11vol.% SiC in the Ni-Co matrix increased hardness more than 60%. The average depth of scratch in the mentioned ...
An organically modified montmorillonite (MMT) was compounded with polybutylene terephthalate (PBT) in a twin-screw extruder. The organoclay PBT nanocomposites were then injection molded by conventional and microcellular methods. Nitrogen was used as the blowing agent. The effect of organoclay content, organoclay size (8 and 35mm), and speed of the screw (80 and 100rpm) on the mechanical and thermal properties were investigated. The results showed that when the MMT content was 1.0wt.%, the nanocomposites have maximum tensile strength, wear resistance, and cell density. Moreover, the larger the particle size, the greater the tensile strength. The screw speed during compounding also affected the mechanical strength. The higher speed of the screw increased the tensile strength of the nanocompo...
A total of 86 experimental fuel pins with various fuel, liner, and cladding candidate materials have been irradiated in the Experimental Breeder Reactor-II (EBR-II) and the Fast Flux Test Facility (FFTF) reactor as part of the SP-100 fuel pin irradiation testing program. Postirradiation examination results from these fuel pin are key in establishing performance correlations and demonstrating the lifetime and safety of the reactor fuel system. This paper provides a brief description of the in-reactor fuel pin tests and presents the most recent irradiation data on the performance of wrought rhenium (Re) liner material and high density UN fuel at goal burnup of 6 atom percent (at. %). It also provides an overview of the significant variety of other fuel/liner/cladding combinations which were irradiated as part of this program and which may be of interest to more advanced efforts.
A WO(3)/TiO(2) composite, hollow-sphere photocatalyst with average diameter of 320 nm and shell thickness of 50 nm was successfully prepared using a template method. UV-vis diffuse reflectance spectra illustrated that the main absorption edges of the WO(3)/TiO(2) hollow spheres were red-shifted compared to the TiO(2) hollow spheres, indicating an extension of light absorption into the visible region of the composite photocatalyst. The WO(3) and TiO(2) phases were confirmed by X-ray diffraction analysis. BET isotherms revealed that the specific surface area and average pore diameter of the hollow spheres were 40.95 m(2)/g and 19 nm, respectively. Photocatalytic experiments indicate that 78% MB was degraded by WO(3)/TiO(2) hollow spheres under visible light within 80 min. Under the same conditions, only 24% MB can be photodegraded by TiO(2). The photocatalytic mineralization of MB, catalyzed by TiO(2) and WO(3)/TiO(2), proceeded at a significantly higher rate under UV irradiation than ...
Graphical abstract: Ordered mesoporous organic-inorganic composite film has been achieved by sol-gel and spin-coating techniques. We believe that the mesoporous composite films have a potential application as a protect coating of bipolar plate material. Display Omitted Research highlights: ? Ordered mesoporous composite film was deposited on the 304 stainless steel. ? This composite film exhibited excellent protective performance in 0.5 M H_2SO_4. ? The film exhibited a high surface tension with water contact angle close to 90"o. - Abstract: The organic-inorganic composite film was deposited on the 304 stainless steel as bipolar plate material for proton exchange membrane fuel cells by spin-coating method. As shown by XRD, N_2 adsorption-desorption and TEM, the composite films exhibit ordered mesoporous structures. The corrosion tests in 0.5 M H_2SO_4 system displayed that, compared with 304SS, the composite films made corrosion potential ...
Secondary caries and restoration fracture remain the two most common problems in restorative dentistry. Release of fluoride ions (F) could be a substantial benefit because F could enrich neighboring...Full Text Available
This study evaluated whether differences in design of 3-dimensional polylactic acid barriers (EPi-Guide and Guidor) would influence hard tissue results in the treatment of Grade II furcations in humans. A multicenter study was conducted, using 40 patients with moderate to advanced bilateral chronic adult periodontitis of the mandibular first or second molars. After flap access, debridement, and root preparation, surgical bone level measurements were taken and membranes were placed on a random basis. Surgical reentry occurred at 1 year. Data collected from all 3 investigative centers were pooled and analyzed using an analysis of variance appropriate for a counterbalancing design. Both barrier materials resulted in significant gains of attachment level and defect reduction. The composite reduction in the vertical component of the osseous defects was greater in the sites treated with Epi-Guide as compared to those treated with Guidor; the ...
Phase II collimators will complement the existing system to improve the expected high RF impedance and limited efficiency of Phase I jaws. An international collaborative effort has been launched to identify novel advanced materials responding to the very challenging requirements of the new collimators. Complex numerical calculations simulating extreme conditions and experimental tests are in progress. In parallel, an innovative modular design concept of the jaw assembly is being developed to allow fitting in alternative materials, minimizing the thermally induced deformations, withstanding accidents and accepting high radiation doses. Phase II jaw assembly is made up of a molybdenum back-stiffener ensuring high geometrical stability and a modular jaw split in threes sectors. Each sector is equipped with a high-efficiency independent cooling circuit. Beam position monitors (BPM) are embedded in the jaws ...
Methods of X-ray diffraction and transmission electron microscopy were used to study the microstructure of dispersion-strengthened Cu-Al2O3 nanocomposites obtained by the method of simultaneous deposition of Cu and Al2O3 from the vapor phase. The effect of the size of particles of the oxide (Al2O3) and of their content on the electrical resistance of the composite has been considered. The results obtained make it possible to suppose that the main structural factor that determines the electrical resistance of the composite are nanodispersed particles of Al2O3 with a size of less than 20 nm.
The low-cycle fatigue properties of the ferritic-martensitic steels MANET I and II and F82H-mod, have been investigated at a temperature of 200 C. The strain-controlled fatigue has been performed with strain ranges between 0,4% and 1,0% and at a strain rate of 8.10{sup -4} s{sup -1}. The steel F82H-mod, is characterised by a higher plastic strain amplitude compared to MANET I and II. Some of the specimens have beenirradiated with a 104 MeV {alpha}-particle beam. The homogeneous implantation of 400 appm He leads to a hardening of the material. At the beginning of the fatigue tests the stress response of the irradiatedspecimens is higher compared to the unirradiated specimens. In general, thematerial shows softening during fatigue. The softening of irradiated material, which is fatigue tested with a high total strain amplitude, is higher than that of the unirradiated material. The ...
Radon appears mainly by diffusion processes from the point of origin following #alpha#- decay of "2"2"6Ra in underground soil and building materials used, in the construction of floors, walls, and ceiling. The transport phenomenon of radon through diffusion is a significant contributor to indoor radon entry. In the present study radon diffusion through sand, cement, mixtures of sand + cement (1:1), sand + cement (2:1), sand + cement (3:1), sand + cement (4:1) has been carried out using LR-115 type II solid state nuclear track detectors (SSNTDs). The radon diffusion coefficient and diffusion lengths have been calculated for different materials. The effect of compaction, which changes the porosity and permeability of the materials, on radon diffusion has also been studied. (author)
Silicones have many desirable properties and as a result are incorporated into a wide range of products. However, they present unique problems that result from their propensity to outgas resulting in residue formation at unexpected places. Hence, the silicone conundrum?when to use these materials and when to beware of potential pitfalls. In this article, an outgassing mechanism unique to ?low outgassing? silicones is discussed. Examples are given where this has led to failures and remediation steps are highlighted.
Research performed at LAMPF during 1985 is reported in the areas of: nuclear and particle physics; atomic and molecular physics; materials science; radiation-effects studies; biomedical research and instrumentation; nuclear chemistry; radioisotope production; and physics theory. Also reported are the status of LAMPF-II, facility development work, and accelerator operations. (LEW)
The paper discusses the role of the Life Management Programme in ensuring a safe operation of the Dukovany nuclear power plant. The Programme involves the following major items: (i) primary circuit materials degradation assessment, (ii) pipeline damage control by the Flow Assisted Corrosion Monitoring and Prediction Programme, and (iii) the DIALIFE diagnostic system. (author)
Batch interaction experiments were performed under aerobic conditions to characterize the adsorption behavior and valence speciation of CoEDTA complexes (equimolar at 10 -5 mol/L) in a series of Pliocene subsurface sediments containing various amounts of Fe and Mn oxides. The experiments were performed in 0.003 mol/L Ca(ClO 4 ) 2 with a solids concentration of 500 g/L at variable pH (4-9) and at the natural pH of the sediments (pH = 8.3). Three of these subaerial sediments (Ringold 1, 2, 3) contained significant quantities of extractable Fe and Mn, while the fourth (Ringold 4) was virtually devoid of sesquioxide precipitates. Microscopic and mineralogic analyses of the most heavily encrusted material (Ringold 2) showed that the oxides existed as intergrain cements and contained crystalline goethite and rancieite/todorokite. Adsorption on a synthetic analog sorbent (0.6 mass % ferrihydrite-coated sand) over a range in pH showed that, while both ...
The intermediate silicon layers detector (ISL) was proposed as a part of the upgraded CDF detector at the RUN-II of the Tevatron mean value of pp collider at Fermilab, scheduled to start in year 2000. The ISL is a large-radius (20-30 cm) silicon tracker with a total active area of about 3.5 m. Located in the region between the silicon vertex detector and the central outer tracker, the ISL will allow tracking in the forward region and significantly improve it in the central area. Together with the SVX II the ISL forms a standalone, 3D silicon tracker. The challenge is to build a low-cost device which provides precise 3 D tracking in a approximately equal to 2 m long area with a minimal amount of material for the supporting structure. The conceptual design and the status of the project are reviewed.
Luminescent transition metal complexes are enjoying a growing interest because of their ubiquitous applications in, e.g., the fields of material science, sensors and (biomedical) diagnostics, and iridium(III) and ruthenium(II) complexes are among the best studied. Due to their long-living excited states, these complexes can have a strong interaction with dioxygen, resulting in luminescence quenching. This oxygen quenching might be regarded as an unwanted effect in luminescence imaging, but, on the other hand, it can be exploited for diagnostic and therapeutic applications as well. After a theoretical introduction concerning the dioxygen quenching mechanism and the parameters involved, in the second part of this review we focus on the possibility of tailoring this quenching by modifying sel...
There have been a number of studies considering the possibility of removing and recovering heavy metals from diluted solutions. These are due, principally, because of the commercial value of some metals as well as in the environmental impact caused by them. The traditional methods for removing have several disadvantages when metals are present in concentrations lower than 100 mg/l. Biosorption, which uses biological materials as adsorbents, has been considered as an alternative method. In this work, variables like pH and biomass chemical pretreatment have been studied for its effect on the capacity for zinc biosorption by Thiobacillus ferrooxidans. Also, studies to determinate the time for zinc adsorption were carried out. Results indicate that a capacity as high as 82.61 mg of Zn(II)/g of dry biomass can be obtained at a temperature of 25 C and that the biosorption process occurs in a time of 30 min. (orig.)
Current light water reactor (LWR) steam generators have been affected by a variety of corrosion and mechanical damage degradation mechanisms. Included are wear caused by tube vibration, intergranular corrosion, pitting, and thinning or wastage of the steam generator tubing and accelerated corrosion of carbon steel supports (denting). The Electric Power Research Institute (EPRI) and the Steam Generator Owners Groups (I, II) have sponsored laboratory and field studies to provide ameliorative actions for the majority of the damage forms experienced to date. Some of the current corrosion mechanisms are aggravated or caused by unique materials choices or materials interactions. New materials have been proposed and at least partially qualified for use in replacement model steam generators, including an advanced LWR design. In so far as possible, the materials choices for the advanced LWR ...
Nanosized particles are important because of their unique properties, different from the bulk, which leads to their enhanced catalytic, photocatalytic and electronic properties. This work has dealt with three different nanoparticle systems in the context of three different aspects of nanoparticle properties: (a) photocatalytis (TiO2/metal) system, (b) luminescence (CdSe) (c) alloying (Pt-Ag and Pd-Ag). The initial photocatalytic enhancement obtained by adding noble metal on semiconductor nanoparticles, degrades as fast as in 15 minutes and questions their long-term performance. XANES measurements on such irradiated systems like TiO2/Au, TiO2/Pt, TiO2/Ir indicates a positive oxidation state of these noble metals which renders them as recombination centers for photo-excited electrons and explains the decreased photocurrent. The oxidation is caused by holes. The EXAFS results also indicate a change of the interfacial structure under the effect of UV-irradiation, thus affecting the ...
"1"4C measurement uses a number of standards and reference materials with different properties. Historically the absolute calibration of "1"4C measurement was tied to 1890 wood, through the 'primary' standard of NBS-OxI (produced by the National Bureau of Standards, now NIST - National Institute of Standards and technology) subsequently replaced by NBS-OxII. These are both internationally calibrated and certified materials, whose "1"4C activities are known absolutely. A second tier of materials, often called secondary standards or reference materials, and including internationally recognised materials such as ANU-sucrose (now also IAEA-C6), Chinese - sucrose and the IAEA C1-C6 series, augmented by additional oxalic acid samples are also used routinely. The activity of these materials has been estimated from large numbers of measurements made ...
A few metal complexes of isatin-isonicotinoylhydrazone with Ni(II), Cr(III), Co(II), Cu(II), Zn(II) and Cd(II) have been prepared and characterized on the basis of elemental analyses, infrared and electronic spectra as well as "1H NMR spectra, conductivity and magnetic measurements. In view of the results obtained, it has been found that two molecules of isatin-isonicotinoylhydrazone are chelated to the central metal ion as bis-uninegative ONO tridentate ligand forming non-electrolytic octahedral metal complexes. (author)
Multi-walled carbon nanotubes (MWNTs) were modified with poly(hexamethylene adipamide) (also known as Nylon 66) via a controlled polymer solution crystallization method. A 'nanohybrid shish kebab' (NHSK) structure was found wherein the MWNT resembled the shish while Nylon 66 lamellar crystals formed the kebabs. These Nylon 66-functionalized MWNTs were used as precursors to prepare polymer/MWNT nanocomposites. Excellent dispersion was revealed by optical and electron microscopies. Nitric acid etching of the nanocomposites showed that MWNT formed a robust network in Nylon 66. Non-isothermal DSC results showed multiple melting peaks, which can be attributed to lamellar thickness changes upon heating. The crystallite sizes L{sub 100} and L{sup 010} of Nylon 66, determined by WAXD, decreased with increasing MWNT contents. Isothermal DSC results showed that crystallization kinetics increased first and then decreased with increasing ...
Composite ZnO/Ag nanoparticles have been formed via the photocatalytic reduction of silver nitrate over the ZnO nanocrystals, their optical, electrophysical and photochemical properties have been investigated. Mie theory has been applied to analyze the structure of the absorption spectra of ZnO/Ag nanocomposite. The irradiation effects upon the optical properties of ZnO/Ag nanostructure have been investigated. It has been found that the irradiation of ZnO/Ag nanoparticles results in electrons accumulation by both the semiconductor and the metallic components of the nanocomposite. It has been found that silver nitrate can be photochemically deposited onto the surface of ZnO nanoparticles under the illumination with the visible light in the presence of the sensitizer - methylene blue. Kinetics of the sensitized Ag(I) photoredution has been studied. It has been concluded that the key stage of this process is the electron injection from ...
This paper presents the first results on formation and study of structure and properties of micro- and nanocomposite combined coatings. By means of modeling the deposition processes (deposition conditions, current density-discharge, plasma composition and density, voltage) we formed the three-layer nanocomposite coatings of Ti-Al-N/Ti-N/Al_2O_3. The coating composition, structure and properties were studied using physical and nuclear-physical methods. The Rutherford proton and helium ion backscattering, scanning electron microscopy with microanalysis, grazing incidence X-ray diffraction, as well as nanohardness tests (hardness) were used. Measurements of wear resistance and corrosion resistance in NaCl, HCl and H_2SO_4 solutions were also performed. For testing mechanical properties such characteristics of layered structures as hardness H, elastic modulus E: H"3/E"2 etc. were measured. It is demonstrated that the formed three-layer ...
Novel hybrid organic/inorganic nanocomposites made of metal oxide and conjugated polymer nanocomposite and its application in bulk-heterojunction solar cells were studied. The composite was composed of different concentrations of strontium titanate (SrTiO_3) and polyaniline doped phosphoric acid. The optimum concentration of strontium titanate was found to be 0.2 v/v. An inorganic-organic photovoltaic device with a structure of Ag/Pani-H_3PO_4-SrTiO_3/Al has been fabricated. The ideality factor value of the diode was found to be 1.8. This n value of the diode implies a deviation from ideal junction behaviour. The barrier height #phi#_b value for the diode was found to be 0.56 eV. The Ag/Pani-H_3PO_4-SrTiO_3/Al diode shows a photovoltaic behaviour with a maximum open-circuit voltage V_o_c of 2.49 V, and short-circuit current I_s_c of 5.6 mA under light illumination #lambda# = 460 nm. The conversion efficiency was found to be 5.2%. It is ...
The GERDA experiment is located in the underground Gran Sasso laboratory. The experiment aims at studying the neutrinoless ?? decay of 76Ge. The implementation of the experiment is divided in two consecutive phases. Phase I will allow within one year of data taking to reach a sensitivity limit for the half life of the process of the order of Formula Not Shown years. Phase II, with an increased amount of active material and a background index lower by one order of magnitude than in Phase I, will allow to reach a half life limit of about Formula Not Shown years. In the present paper a brief review of the status of the experiment and its perspectives is given.
The activities and results of a Small Business Innovation Research Phase II project entitled ''Rapid Tools for Joint Inversion and Imaging'' are presented. Research and development on three-dimensional methods to recover distributions of material property values from sparse data are reported. Innovations using artificial neural networks and extended Kalman filtering are described. The report also covers investigations on upscaling and downscaling, segmentation for data processing, and applications to ground penetrating radar and geohydraulic tomography.
The authors experimentally study the separate stages of the determination of iodine in thyroidin by the combustion method in a flask with oxygen. The monotypic, conventional procedures and the procedure of Kolii and Pakhomov were studied. With addition of potassium iodide, a sixfold amount (compared with the initial) of iodine is liberated. Further, the liberated iodine is titrated by sodium thiosulfate. The authors find the degree of influence of a high nitrogen content on the determination of iodine in organic compounds. The procedure developed for the quantitative determination of the iodine in thyroidin by the combustion method is simple, fairly rapid, and can be used for the reliable control of the quality of thyroidin preparations and its starting raw material.
A simple and rapid procedure was developed for the purification of cyclotron-produced {sup 203}Pb via the {sup 203}Tl(d,2n) {sup 203}Pb reaction. A Pb(II) selective ion-exchange resin, with commercial name Pb Resin from Eichrom Technologies, Inc., was used to purify {sup 203}Pb from the cyclotron-irradiated Tl target with excellent recovery of the enriched Tl target material. The purified {sup 203}Pb was used to radiolabel the monoclonal antibody Herceptin. The in vitro and in vivo properties of the {sup 203}Pb radioimmunoconjugate were evaluated.
Steel is one of the most versatile materials known to mankind. It is used in a variety of applications. In many of these applications, it is exposed to the atmosphere, leading to rust formation, which weakens structures made using steel. Hence, protection is important. The popular methods to prevent corrosion are painting, galvanizing, electroplating etc. The widely used Chrome etching process is very effective in corrosion inhibition as well as in hardening the steel. But, Chromium and its compounds are highly placed among the toxic chemicals listed under pollution prevention initiatives of the EPA. Hence, it was decided to find alternatives to this process.
Gasification and hydrogenation are the two basic routes for coal processing. Accounts are given of various low-temperature processes in coal gasification route A: air separation, removal of sour gas by the Rectisol process, liquid nitrogen washing, the material balance and utility consumption of these processes, plus low-temperature gas separation, partial condensation and methane washing. There are also accounts of the low-temperature processes involved in gasification route B: i.e., in the indirect coal liquefaction and direct liquefaction carried out in the Sasol II and III processes. (3 refs.) (In Japanese)
We report investigations of enhancement in material conversion efficiency of KDP for SHG applications. The limitation of conventional technique of growing KDP crystal was overcome in the present work by adopting a growth method to grow KDP directly in type-II phase matching direction. The conventional technique results in #approx#30% of the crystal volume usable for SHG applications whereas the present method has resulted in enhancing it to #approx#90%. The orientation of the element was confirmed by frequency conversion experiment using Nd:YAG laser. The UV-vis transmittance obtained was 92%. The interferometric results show that the crystals have excellent optical homogeneity.
This executive summary presents the motivation, structure, objectives, methodologies and results of the first stage of the international DECOVALEX project - DECOVALEX I (1992-1995). The acronym stands for Development of Coupled Models and their Validation against Experiment in Nuclear Waste Isolation, and the project is an international effort to develop mathematical models, numerical methods and computer codes for coupled thermo-hydro-mechanical processes in fractured rocks and buffer materials for geological isolation of spent nuclear fuel and other radioactive wastes, and validate them against laboratory and field experiments. 24 refs.
The single specimen unloading compliance technique has become the preferred method for evaluating J-integrals. It involves data acquisition and analysis using a computer. This paper describes in detail the development of a simple experimental system and related software that can be used in a laboratory equipped with a microcomputer and with access to a minicomputer. The effects of loading rate, test temperature, specimen geometry and material composition can be readily evaluated using this system. The results on a pressure vessel steel and an #alpha#-#beta# titanium alloy are discussed in Part II. (author).
In this article, we describe a method used to prepare an in situ sodium-activated, organomodified bentonite clay/styrene-butadiene rubber nanocomposite master batch via a latex blending technique. The clay master batch was used for compound formulation. Octadecyl amine was used as an organic intercalate. The clay was purchased from local suppliers and was very cheap. Sodium chloride was used for in situ activation of the clay. The wide-angle X-ray diffraction data indicated that the in situ sodium activation helped to increase the intergallery distance from 1.28 to 1.88 nm. A transmission electron micrograph indicated intercalation and partial exfoliation. The thermal properties were relatively better in the case of the sodium-activated, organomodified bentonite-clay-containing compound. A...
SnO2/graphene nanocomposites have been fabricated by a simple chemical method. In the fabrication process, the control of surface charge causes echinoid-like SnO2 nanoparticles to be formed and uniformly decorated on the graphene. The electrostatic attraction between a graphene nanosheet (GNS) and the echinoid-like SnO2 particles under controlled pH creates a unique nanostructure in which extremely small SnO2 particles are uniformly dispersed on the GNS. The SnO2/graphene nanocomposite has been shown to perform as a high capacity anode with good cycling behavior in lithium rechargeable batteries. The anode retained a reversible capacity of 634 mA?h?g?1 with a coulombic efficiency of 98% after 50 cycles. The high reversibility can be attributed to the mechanical buffering by the GNS against...
Synthesis, morphology, structural and optical characteristics of SiC NWs and SiC/C nanocomposites with an inverse opal lattice have been investigated. The samples were prepared by carbothermal reduction of silica (SiC NWs) and by thermo-chemical treatment of opal matrices (SiC/C) filled with carbon compounds which was followed by silicon dioxide dissolution. It was shown that the nucleation of SiC NWs occurs at the surface of carbon fibers felt. It was observed three preferred growth direction of the NWs: [111], [110] and [112]. HRTEM studies revealed the mechanism of the wires growth direction change. SiC/C- HRTEM revealed in the structure of the composites, except for silicon carbide, graphite and amorphous carbon, spherical carbon particles containing concentric graphite shells (onion-like particles).
Abstract Aims: To develop a new nano composite of multi walled carbon nanotubes (MWNTs) with enhanced antimicrobial activity. Methods and Results: A novel antimicrobial nanocomposite [MWNT epilson polylysine (MEPs)] was synthesized via covalent attachment of epilson polylysine on MWNTs with hexamethylene diisocyanate (HDI) as the coupling agent. UV visible spectra and Fourier transform infrared spectra (FT IR) investigations indicate that MEPs is stable, with epilson polylysine leaching effectively eliminated. When compared to MWNTs, the new nano composite MEPs exhibits enhanced antimicrobial activities. In 20 mg l 1 suspensions, significant increases of 72 1, 64 5 and 69% against Escherichia coli, Pseudomonas aeruginosa and Staphylococcus aureus can be observed. The deposited film of MEPs...
A sensitive hydrogen peroxide (H2O2) sensor was fabricated based on graphene-Pt (GN-Pt) nanocomposite. The GN-Pt was synthesized by photochemical reduction of K2PtCl4 on GNs, and characterized by atomic force microscope (AFM), transmission electron microscope (TEM), and energy-dispersive X-ray spectroscopy (EDS). Electrochemical investigations indicated that the GN-Pt exhibited a high peak current and low overpotential towards the reduction of H2O2. The GN-Pt modified glass carbon electrode displayed a wide linear range (2-710mM), low limit of detection (0.5mM) and good selectivity for detection of H2O2 with a much higher sensitivity than that of Pt nanoparticles or graphene modified electrode.
This study describes the effect of treatment of Bis(3-triethoxysilyl propyl)tetrasulfane (silane coupling agent, Si69, TESPT) on in situ sodium activated, organo modified bentonite clay - styrene butadiene rubber (SBR) nanocomposite. transmission electron microscopy and Wide angle X-ray diffraction indicated the intercalation as well as partial exfoliation in both the organoclay and silane treated organoclay compound. It was found that about 5% of silane with respect to clay was the optimum dose for the treatment. Around 15% improvement in tensile and tear strength was observed due to silane treatment. Silane treated organoclay exhibited substantial improvement of the fatigue life, compression set, and rebound property. A detailed study of physical property was carried out. A comparison wi...
Direct electrochemistry and electrocatalysis of catalase (Cat) was studied based on a nano-composite film consisting of amine functionalized graphene and gold nanoparticles (AuNPs) modified glassy carbon electrode. Graphene was synthesized chemically by Hummers and Offeman method and then was functionalized with amino groups via chemical modification of carboxyl groups introduced on the graphene surface. The nano-composite film showed an obvious promotion of the direct electron transfer between Cat and the underlying electrode, which attributed to the synergistic effect of graphene-NH2 and AuNPs. The resultant bioelectrode retained its biocatalytic activity and offered fast and sensitive H2O2 quantification. Under the optimized experimental conditions, hydrogen peroxide was detected in the...
A superhydrophobic SiO2/nylon 6,6 nanocomposite coating was fabricated by a facile casting process. Compared with the intrinsically hydrophilic pure nylon 6,6, the as-prepared coating displayed a superhydrophobic property in the pH range from 1 to 14. It was also found that the resulting water contact angles of the as-prepared surface were always larger than 159?, but the sliding angles had an obvious decrease from about 33.4??1? as the content of SiO2 nanoparticles increased. In addition, a transition from the transitional superhydrophobic state between Wenzel?s and Cassie?s state to the Cassie?s state was observed.
The deportation of trophoblast debris from the placenta was first documented over 100 years ago, and today we know that the deported material ranges from multinucleated syncytial knots/sprouts to trophoblast-derived nanoparticles. However little is known about the effect of trophoblast debris on maternal physiology since it is difficult to investigate these effects in vivo in women. Animal models have been reported but they have provided relatively little information. Most of our current knowledge regarding the effects of trophoblast debris on maternal systems is provided by studies using trophoblast debris obtained from in vitro models of the human placenta. Herein we review the animal models and the in vitro studies, which, between them, suggest that deported trophoblast material may pla...
The Integral Fast Reactor is an innovative liquid metal reactor concept that is being developed by Argonne National Laboratory. It takes advantage of the properties of metallic fuel and liquid metal cooling to offer significant improvements in reactor safety, operation, fuel cycle economics, environmental protection, and safeguards. The plans for demonstrating the IFR fuel cycle, including its waste processing options, by processing irradiated fuel from the Experimental Breeder Reactor-II fuel in its associated Fuel Cycle Facility have been developed for the first refining series. This series has been designed to provide the data needed for the further development of the IFR program. An important piece of the data needed is the recovery of TRU material during the reprocessing and waste operations.
The Integral Fast Reactor is an innovative liquid metal reactor concept that is being developed by Argonne National Laboratory. It takes advantage of the properties of metallic fuel and liquid metal cooling to offer significant improvements in reactor safety, operation, fuel cycle economics, environmental protection, and safeguards. The plans for demonstrating the IFR fuel cycle, including its waste processing options, by processing irradiated fuel from the Experimental Breeder Reactor-II fuel in its associated Fuel Cycle Facility have been developed for the first refining series. This series has been designed to provide the data needed for the further development of the IFR program. An important piece of the data needed is the recovery of TRU material during the reprocessing and waste operations.
Platinum(II) complexes have been investigated in the hydration of alkynes. These catalysts offer improved regioselectivity over Hg(II) counterparts. 1 fig., 2 tabs.
Full text of publication follows: Large-scale problems such as nuclear waste disposal are increasingly recognized to be interconnected to small scale-mechanisms. Thus, synchrotron-based high-resolution analytical X-ray probes become important tools for exploring the micro-scale chemical reactivity of heterogeneous barrier materials used in nuclear waste repositories. In this study the layout of the micro-XAS beamline at the Swiss Light Source (SLS) will be presented. The beamline is optimized towards micro beam experiments ({approx}1 x 1 {mu}m{sup 2}) in the hard-X-ray regime (4 - {approx}22 keV) and allows to combine micro X-ray fluorescence (micro-XRF), micro X-ray absorption spectroscopy (micro- XAS), and micro X-ray diffraction (micro-XRD) investigations with radioactive samples. Furthermore, the potential of micro-XRF/XAS/XRD for acquiring spatially resolved molecular level information on the speciation and structural coordination environment of radionuclides ...
The thermal stability of low-friction Me-C/a-C:H coatings is important for their potential applications in the tool and automotive industry. Recently we showed that CrC _x/a-C:H coatings prepared by unbalanced magnetron sputtering of a Cr target in Ar + CH_4 glow discharges exhibit a nanocomposite structure where metastable fcc CrC nanocrystals are encapsulated by an a-C:H phase. Here, we present the structural evolution of these nanocomposite CrC/a-C:H coatings during annealing. High-temperature X-ray diffraction in vacuum and differential scanning calorimetry (DSC) combined with thermo-gravimetric analysis in Ar atmosphere indicate decomposition of the formed metastable fcc CrC phase and subsequent formation of Cr_3C_2 and Cr_7C_3 and structural transformation of the a-C:H matrix phase towards higher sp"2 bonding contents at temperatures above 450 deg. C. Combined DSC and mass spectrometer analysis as well as elemental profiling after ...
A method for estimating the form of magnetic nanoparticles in composite film structures based on the observation of ferromagnetic resonance phenomenon is offered. Within the model of the effective medium, an explanation is given for experimentally observed concentration and temperature dependences of resonant fields for composite nanosystem (Co45Fe45Z10) f +(Al2O3)100?f .
The synthesis of a new kind of magnetic, fluorescent multifunctional nanoparticles (~30 nm in diameter) was demonstrated, where multiple fluorescent CdTe quantum dots (QDs) are covalently linked...Full Text Available
Batch interaction experiments were performed under aerobic conditions to characterize the adsorption behavior and valence speciation of CoEDTA complexes (equimolar at 10{sup -5} mol/L) in a series of Pliocene subsurface sediments containing various amounts of Fe and Mn oxides. The experiments were performed in 0.003 mol/L Ca(ClO{sub 4}){sub 2} with a solids concentration of 500 g/L at variable pH (4-9) and at the natural pH of the sediments (pH = 8.3). Three of these subaerial sediments (Ringold 1, 2, 3) contained significant quantities of extractable Fe and Mn, while the fourth (Ringold 4) was virtually devoid of sesquioxide precipates. Microscopic and mineralogic analyses of the most heavily encrusted material (Ringold 2) showed that the oxides existed as intergrain cements and contained crystalline goethite and rancieite/todorokite. Adsorption on a synthetic analog sorbent (0.6 mass% ferrihydrite-coated sand) over a range in pH showed that, while both ...
The Fast Flux Test Facility (FFTF) is a 400-MWt, sodium-cooled reactor located on the Hanford Site near Richland, Washington, USA. The FFTF is owned by the U.S. Department of Energy and is operated by the Westinghouse Hanford Company. The FFTF was designed to test fuels and materials for use in liquid metal reactors. Since initial operation in 1982, anticipated breaches of experimental fuel pins have released fission products, including cesium, into the primary sodium. Because of its high volatility, cesium vaporizes into the cover gas space, where it condenses on components and equipment and is transported into the cover gas outlet. Because of the long half-life of "1"3"7Cs, these deposits result in long-term, local radiation levels that make contact maintenance difficult. Thus, a cesium trap was installed in FFTF to reduce the cesium level in the sodium. The trap could also permit a Run Beyond Cladding Breach (RBCB) program without compromising the sodium purity. ...
Two enantioselective, potentiometric membrane electrodes (EPMEs) based on maltodextrins with different value of dextrose equivalent (DE) (maltodextrin I: DE 4.0-7.0; maltodextrin II: DE 16.5-19.5) were proposed for the assay of baclofen enantiomers in baclofen raw materials and from its pharmaceutical formulation, Norton-Baclofen tablets. The slopes of the electrode function of the proposed electrodes were 55.0 mV/pS-baclofen for maltodextrin I-based electrode and 59.0 mV/pR-baclofen for maltodextrin II-based electrode and the detection limits were 1.34 x 10(-6) mol l(-1) (S-baclofen) and 2.52 x 10(-10) mol l(-1) (R-baclofen), respectively. The surfaces of the electrodes are stable and easily renewable by simply polishing on alumina paper. PMID:15598435
The BEATRIX-II irradiation experiment is an in-situ tritium release experiment being carried out in the Fast Flux Test Facility (FFTF) reactor to evaluate the tritium release characteristics of fusion solid breeder materials. A sophisticated tritium gas handling system has been developed to continuously monitor the tritium recovery from the specimens and facilitate tritium removal from the experiment's sweep gas flow stream. The in-situ recovery experiment accommodates two different in-reactor specimen canisters with individual gas streams and temperature monitoring/control. Ionization chambers have been specifically designed to respond to the rapid changes in the tritium release rate at the anticipated tritium concentrations. Two ceramic electrolysis cells have proved effective in reducing the moisture in the gas streams to hydrogen/tritium. A tritium getter system, capable of reducing the tritium level by a factor greater than 4000, ...
In the case wherein nonlinear seismic response analyses are carried out, the response values vary due to the variations in materials and modeling. In this paper, nonlinear analyses of several random variables are carried out using: i. a conventional method; ii. a two-point estimation method (i. and ii. are simplified methods); and iii. Monte Carlo simulation (detailed method) to examine the variability of the response in the excessive nonlinear range for seismic responses of shear walls. The analyses are performed to a PWR-3 loop type reactor building which is one of the most typical reactor buildings in Japan. The variations are considered in specified compressive strength of concrete, concrete damping factor, shear wave velocity of soil and shapes of shear stress-strain relation curves of shear walls. As the results by the two simplified methods closely matched the Monte Carlo simulation results, the appropriateness for ...
The aim of this paper is to investigate the possible displacement of natural gypsum (CaSO{sub 4}2H{sub 2}O) in cement with an alternative setting retarder, such as the industrial by-product derived from flue gas desulfurization process called FGD gypsum. These calcium-sulfate-bearing materials (CSBM), alone or in mixtures, were ground with clinker both in laboratory and industrial scale to examine their influence on the physical and mechanical properties of cement, as well as on the industrial production line of cement. From the present work, it is extracted that the use of mixtures of sulfate-bearing materials with gypsum seems to be advantageous for the actual control of setting time. The addition of FGD gypsum increases setting time without affecting compressive strength profile. During the industrial trial, the formation of hemihydrate form of calcium sulfate dihydrate has a profound regulatory effect on the setting and strength performance ...
This paper discusses how the U.S. Liquid Metal Reactor Development Program has been restructured to carry out R and D on advanced reactor technology. The program gives particular emphasis to improvements to reactor safety. The new directions are based on the technology of the integral fast reactor (IFR). Much of the basis for superior safety performance using IFR technology has been experimentally verified and aggressive programs continue in EBR-II and TREAT. Progress has been made in demonstrating both the metallic fuel and the new electrochemical processes of the IFR. The FFTF facility is converting to metallic fuel; however, FFTF also maintains a considerable U.S. program in oxide fuels. In addition, generic programs are continuing in steam generator testing, materials development, and with international cooperation, aqueous reprocessing.
A simple and rapid procedure was developed for the purification of cyclotron-produced "2"0"3Pb via the "2"0"3Tl(d,2n) "2"0"3Pb reaction. A Pb(II) selective ion-exchange resin, with commercial name Pb Resin from Eichrom Technologies, Inc., was used to purify "2"0"3Pb from the cyclotron-irradiated Tl target with excellent recovery of the enriched Tl target material. The purified "2"0"3Pb was used to radiolabel the monoclonal antibody Herceptin. The in vitro and in vivo properties of the "2"0"3Pb radioimmunoconjugate were evaluated.
Objective.The objective of this study was to use the newly synthesized poly(quaternary ammonium salt) (PQAS)-containing polyacid to formulate the light-curable glass-ionomer cements and study the effect of the PQAS on the compressive strength and antibacterial activity of the formed cements.Materials and methods.The functional QAS and their constructed PQAS were synthesized, characterized and formulated into the experimental high-strength cements. Compressive strength (CS) and Streptococcus mutans viability were used to evaluate the mechanical strength and antibacterial activity of the cements. Fuji II LC cement was used as control. The specimens were conditioned in distilled water at 37 degrees C for 24 h prior to testing. The effects of the substitute chain length, loading as well as gra...
Morphology of castellated Be tiles from the belt limiter exposed to the JET plasma for 56,000 s was examined on both sides of castellated grooves, on plasma-facing and side surfaces of the tiles. The essential results are (i) deuterium retention in the castellated grooves and in other locations is associated with co-deposition of carbon; (ii) the decay length of deposition in the castellation is around 1.5 mm; (iii) no deuterium is detected in bulk Be; (iv) bridging of gaps by molten beryllium occurred but gaps were not filled with Be; (v) on side surfaces of the tiles the formation of BeO layer was detected at a distance of 20 mm and more from the plasma-facing surface. The consequences for a long-term operation of a reactor-class device with several different plasma-facing materials are addressed.
Electron charge distributions are presented for Nb_3Ge, Nb_3Al, and two other hypothetical A-15 structures. Results indicate that the bonding in these materials is mainly metallic in character with some covalentlike bonding between Nb-chain atoms. We find significant coupling between neighboring chains and also between chain atoms and atoms at the cubic site. Comparison is made with various theoretical models. Investigation of the charge character of states near E/sub F/ suggests further developments in current theories on the structural transformation of A-15 compounds. The effect of chain dimerization on electronic states and charge distribution of Nb_3Ge is also investigated.
Electron charge distributions are presented for Nb3Ge, Nb3Al, and two hypothetical A-15 structures. Results indicate that the bonding in these materials is mainly metallic in character with some covalentlike bonding between Nb-chain atoms. We find significant coupling between neighboring chains and also between chain atoms and atoms at the cubic site. Comparison is made with various theoretical models. Investigation of the charge character of states near EF suggests further developments in current theories on the structural transformation of A-15 compounds. The effect of chain dimerization on electronic states and charge distribution of Nb3Ge is also investigated.
Electron charge distributions are presented for Nb/sub 3/Ge, Nb/sub 3/Al, and two other hypothetical A-15 structures. Results indicate that the bonding in these materials is mainly metallic in character with some covalentlike bonding between Nb-chain atoms. We find significant coupling between neighboring chains and also between chain atoms and atoms at the cubic site. Comparison is made with various theoretical models. Investigation of the charge character of states near E/sub F/ suggests further developments in current theories on the structural transformation of A-15 compounds. The effect of chain dimerization on electronic states and charge distribution of Nb/sub 3/Ge is also investigated.
The overall objective of the study in this report was to gather data on waste management technologies to allow comparison of various alternatives for managing municipal solid waste (MSW). The specific objectives of the study were to: 1. Compile detailed data for existing waste management technologies on costs, environmental releases, energy requirements and production, and coproducts such as recycled materials and compost. Identify missing information necessary to make energy, economic, and environmental comparisons of various MSW management technologies, and define needed research that could enhance the usefulness of the technology. 3. Develop a data base that can be used to identify the technology that best meets specific criteria defined by a user of the data base. Volume I contains the report text. Volume II contains supporting exhibits. Volumes III through X are appendices, each addressing a specific MSW management technology. Volumes XI ...
Since the very high temperature reactor (VHTR) components such as hot gas ducts and intermediate heat exchanger (IHX) are operated during a design life of 30 to 60 years at 950 .deg. C and 3-8MPa in He impurities, their components are required to have good high temperature strength, creep-rupture strength, high temperature stability, and good corrosion resistance. Among them, creep properties are the most important, because the integrity of their components should be preserved during a design life of over 30 years at the maximum operating temperature up to 1000 .deg. C. So far, there are no materials approved by ASME III which is a nuclear code for temperatures reaching 1000 .deg. C, and until now, a material selection is still left as a key issue. Some leading candidate alloys can be selected from the high temperature materials approved by ASME VIII. Alloy 617 is considered as a prospective material ...
New tetradentate N(2)O(2) donor Schiff bases and their mononuclear Co(II), Ni(II), Cu(II), and Pd(II) complexes were synthesized and characterized extensively by IR, (1)H-, (13)C-NMR, mass, ESR, conductivity measurements, elemental and thermal analysis. Specifically the magnetic and electronic spectral measurements demonstrate the octahedral structures of cobalt(II), nickel(II) complexes and square planar geometries of copper(II), palladium(II) complexes. All the ligands and complexes were screened for their in vitro antibacterial activity against two gram-positive bacteria (Bacillus subtilis, Staphylococcus aureus) and two gram-negative bacteria (Escherichia coli, Klebsiella pneumonia). In this study, Pd(II) complexes exhibited potent antibacterial activity against B. subtilis, S. aureus whereas ...
Some acylhydrazine derived ONO donor Schiff bases and their Co(II) and Ni(II) complexes have been prepared having the same metal ion (cation) but different anions. These synthesized metal(II)...Full Text Available
Silver silica nanocomposites were obtained by the sol-gel technique using tetraethyl orthosilicate (TEOS) and silver nitrate (AgNO{sub 3}) as precursors. The silver nitrate concentration was varied for obtaining composites with different nanoparticle sizes. The structural and microstructural properties were determined by x-ray diffractometry (XRD), Fourier transform infrared spectroscopy (FTIR) and transmission electron microscopy (TEM). X-ray photoelectron spectroscopic (XPS) studies were done for determining the chemical states of silver in the silica matrix. For the lowest AgNO{sub 3} concentration, monodispersed and spherical Ag crystallites, with an average diameter of 5 nm, were obtained. Grain growth and an increase in size distribution was observed for higher concentrations. The occurrence of surface plasmon resonance (SPR) bands and their evolution in the size range 5-10 nm is studied. For decreasing nanoparticle size, a redshift and broadening of the ...
Simple and low cost biosensor based on screen-printed electrode for sensitive detection of some alkylphenols was developed, by entrapment of HRP in a nanocomposite gel based on single-walled carbon nanotubes (SWCNTs) and 1-butyl-3-methylimidazolium hexafluorophosphate ([BMIM][PF(6)]) ionic liquid. Raman and FTIR spectroscopy, CV and EIS studies demonstrate the interaction between SWCNTs and ionic liquid. The nanocomposite gel, SWCNT-[BMIM][PF(6)] provides to the modified sensor a considerable enhanced electrocatalytic activity toward hydrogen peroxide reduction. The HRP based biosensor exhibits high sensitivity and good stability, allowing a detection of the alkylphenols at an applied potential of -0.2V vs. Ag/AgCl, in linear range from 5.5 to 97.7?M for 4-t-octylphenol and respectively, between 5.5 and 140?M for 4-n-nonylphenol, with a response time of about 5s. The detection limit was 1.1?M for 4-t-octylphenol, and respectively 0.4?M for ...
Electrodeposition of tertiary alumina/yttria/carbon nanotube (Al2O3/Y2O3/CNT) nanocomposite by using pulsed current has been studied in this investigation. Coating process has been performed on nickel sulphate bath and nanostructure of obtained compound layer is examined with high precision figure analysis of SEM nanographs. The effects of process variables, i.e., Y2O3 concentration, treatment time, frequency and duty cycle, have been experimentally studied. Statistical methods are used to achieve the minimum of corrosion rate and average size of nanoparticles. Finally the contribution percentage of different effective factors is revealed and confirmation run shows the validity of obtained results. Also it has been revealed that by changing the size of nanoparticles, corrosion properties o...
A method of kinetic analysis applicable to non-isothermal oxidation processes of ceramic nanocomposites is presented using Ti-Si-C-N powder as the substrate. The nanoparticle size and phase composition were determined using high-resolution transmission electron microscopy and X-ray diffraction (XRD). Thermogravimetric measurements were carried out for powder samples in dry air in the temperature range 298-1770 K. The following heating rates were applied: 3, 5, 10, 20 K min{sup -1}. Mass spectrometry was used to analyze gaseous oxidation products and solid products were identified by the XRD technique. The Coats-Redfern equation was applied for the kinetic analysis. For each stage of the oxidation kinetic models, the best accuracy was achieved using a series of criteria, and then the A and E parameters of the Arrhenius equations were estimated. Both linear regression and artificial neural networks were applied in testing kinetic models.
Reactive milling of NiO + Al powder mixture resulted in the formation of NiAl-Al_2O_3 nanocomposite powders, with a crystallite size of about 20 nm. The Hall-Williamson analysis revealed that NiAl showed an orientation dependent crystallite size after short processing time and orientation dependent internal strain after long milling time. Both anisotropies were removed by heating the powders in the differential scanning calorimetry. Calorimetric studies showed one exothermic effect attributed to the reduction reaction of NiO and endothermic one associated with melting of Al. Two methods were applied for powders compaction: resistance sintering and pulse electric discharge. In both cases the densities of abut 90% of the theoretical value were achieved. A significant increase in average NiAl crystallites size in compacted samples was observed, up to several hundreds of nanometers.(author)
Direct electrochemistry and electrocatalysis of catalase (Cat) was studied based on a nano-composite film consisting of amine functionalized graphene and gold nanoparticles (AuNPs) modified glassy carbon electrode. Graphene was synthesized chemically by Hummers and Offeman method and then was functionalized with amino groups via chemical modification of carboxyl groups introduced on the graphene surface. The nano-composite film showed an obvious promotion of the direct electron transfer between Cat and the underlying electrode, which attributed to the synergistic effect of graphene-NH2 and AuNPs. The resultant bioelectrode retained its biocatalytic activity and offered fast and sensitive H2O2 quantification. Under the optimized experimental conditions, hydrogen peroxide was detected in the concentration range from 0.3 to 600 ?M with a detection limit of 50 nM at S/N = 3. The biosensor exhibited some advantages, such as short time respond (2 s), ...
This paper reports the presence of face centered cubic cobalt precipitates inside tungsten carbide in nanocomposite of WC-Co synthesized by spray conversion processing. EDS was used to identify the presence and micro-diffraction was employed to determine the nature of the precipitates. There is entrapment of cobalt in tungsten carbide during the spray conversion process used to form WC/Co powder. During consolidation, at high temperatures, the cobalt attains enough mobility to precipitate inside WC. A vanadium containing compound was seen at the interfaces in samples which incorporated VC as a grain growth inhibitor. (orig.)
The difficulty in making good Ohmic contact at the interfaces with p-doped ZnSe is an important problem hindering the realization of blue-light-emitting diode lasers based on the II-VI semiconductor technology. So far no metal or semiconductor material has been found to have a low enough barrier at the (001) interface with ZnSe. A possible solution to this problem is the insertion of a so-called {ital barrier-reduction layer} at the interface with ZnSe. We have investigated the interface formation energies and valence-band offsets at the (001) interface between Al{sub x}Ga{sub 0.5{minus}x}In{sub 0.5}P and ZnSe. The results of our calculations show the existence of a strong interdependence between the valence-band offset and the interface geometric structure. The interface is found to have structural and electronic similarities to the GaAs-ZnSe(001) system. The very low values obtained for the valence-band offset confirm the possibility of using ...
Lunar resource utilization has focused principally on the extraction of oxygen from the lunar regolith. A number of schemes have been proposed for oxygen extraction from Ilmenite and Anorthite. Serendipitously, these schemes have as their by-products (or more directly as their "waste products"), materials needed for the fabrication of thin film silicon solar cells. Thus lunar surface possesses both the elemental components needed for the fabrication of silicon solar cells and a vacuum environment that allows for vacuum deposition of thin film solar cells directly on the surface of the Moon without the need for vacuum chambers. In support of the US space exploration initiative a new architecture for the production of thin film solar cells on directly on the lunar surface is proposed. The paper discusses experimental data on the fabrication and properties of lunar glass substrates, evaporated lunar regolith thin films (anti-reflect coatings and insulators), and ...
Context: Our previous models of a giant planet migrating through an inner protoplanet/planetesimal disk find that the giant shepherds a portion of the material it encounters into interior orbits, whilst scattering the rest into external orbits. Scattering tends to dominate, leaving behind abundant material that can accrete into terrestrial planets. Aims: We add to the possible realism of our model by simulating type I migration forces which cause an inward drift, and strong eccentricity and inclination damping of protoplanetary bodies. This extra dissipation might be expected to enhance shepherding at the expense of scattering, possibly modifying our previous conclusions. Methods: We employ an N-body code that is linked to a viscous gas disk algorithm capable of simulating: gas accretion onto the central star; gap formation in the vicinity of the giant planet; type II migration of the giant planet; type I migration of ...
Ion Beam Induced Luminescence (IBIL) and Ion Beam Induced Charge Collection (IBICC) have been applied in the study of the luminescence emission efficiency and investigation of the homogeneity of the luminescence emission in phosphors. The IBIL imaging was performed by using sharply focused ion beams or broad/partially-focused ion beams. The luminescence emission homogeneity in samples was examined to reveal possible distributed crystal-defects that may lead to the inhomogeneity of the luminescence emission in samples.The purpose of the study is to search for suitable luminescent thin films that have high homogeneity of luminescence emission, large IBIL efficiency under heavy ion excitation, and can be placed as a thin layer on the top of microelectronic devices to be analyzed with Ion Photon Emission Microscopy (IPEM). The emission yield was found to be low for organic materials, due to saturation of the light output dependence on the energy deposition of heavy ...
The PuO/sub 2/ cask or SP 5320-2 and 3 cask is designed for surface shipment of americium or plutonium. The cask design was physically tested to demonstrate that it met the criteria specified in US ERDA Manual Chapter 0529, and Chapter I, Interstate Commerce Commission. The package has been assessed for transport of up to 357 grams of plutonium (403 grams PuO/sub 2/ powder) and up to 176 grams of americium (200 grams AmO/sub 2/ powder), having a maximum decay heat of 203 watts. Criticality evaluation alone would allow the shipment as Fissile Class II but the radiation level of the cask, measured at the time of shipment, may exceed 50 mrem/h at the surface and require shipment as Fissile Class III. Sample calculations address only the more restrictive of the two materials, which in most cases is /sup 238/PuO/sub 2/.
The Sp-100 reactor is a lithium-cooled high-temperature fast-spectrum reactor. The fuel is UN. The cladding is fabricated from PWC-11, a Nb alloy, as are all the primary structural components. A reactor lifetime of up to ten years with an operating temperature of 1370 K is required. The accumulated fluence is expected to be 6 x10"2"2 n/cm"2. The damage, which could result in swelling or embrittlement, anneals out as fast as it occurs for the majority of the structure. This has been confirmed by earlier radiation testing. A number of components, however, are exposed to lower temperatures and the reactor design and materials selection for these components must take this into consideration. Radiation effects must also be considered for the UN fuel, bearing materials, etc. To data an instrumented experiment, MOTO 1000A, has been conducted in the FFTF reactor and as uninstrumented experiment SPM-1 in the EBR-II reactor. In this ...
The plastic displacements around Knoop indentations made in hard titanium/aluminum multilayered films on soft aluminum alloy substrates have been studied. Indentations were cross-sectioned and imaged using the focused-ion-beam (FIB) milling and high-resolution scanning electron microscopy (SEM), respectively. The FIB milling method has the advantage of removing material in a localized region without producing mechanical damage to the specimen. The micrographs of the cross-sectioned indentations indicate that most of the plastic deformation around the indentation is dominated by the soft aluminum substrate. There is a very small change in the multilayered film thickness around the indentation{emdash}less than 10{percent}. The plastic deformation of the thin film resembles a membrane being deflected by a localized pressure gradient across the membrane. Stress-induced voids are also observed in the multilayered film, especially in the area around the indentation apex. ...
Natural, formaldehyde-treated and copolymer-grafted orange peels were evaluated as adsorbents to remove lead ions from aqueous solutions. The optimum pH for lead adsorption was found to be pH 5. The adsorption process was fast, reaching 99% of sorbent capacity in 10 min for the natural and treated biomasses and 20 min for the grafted material. The treated biomass showed the highest sorption rate and capacity in the batch experiments, with the results fitting well to a pseudo-first order rate equation. In the continuous test with the treated biomass, the capacity at complete exhaustion was 46.61 mg g{sup -1} for an initial concentration of 150 mg L{sup -1}. Scanning electronic microscopy and energy dispersive X-ray spectroscopy indicated that the materials had a rough surface, and that the adsorption of the metal took place on the surface. Fourier transform infrared spectroscopy revealed that the functional groups responsible for metallic ...
The sulfur-iodine (SI) thermochemical cycle is one of the main candidate methods to produce hydrogen from non-fossil sources like nuclear (GEN IV reactor) or solar thermal power. A major issue for the successful implementation of the SI cycle is the selection of technically viable and economic materials for construction of process components, particularly heat exchangers. Challenging conditions are encountered in each of the three sections of the SI cycle due to the corrosive chemicals present, including sulfuric acid, iodine, hydroiodic acid, sulfur dioxide, hydrogen, oxygen, and others. In Section I, aqueous, non-aqueous (liquid iodine), and gaseous multi-component phases are present at about 120 {sup o}C and 0.7 MPa. Section II involves gaseous and aqueous phases of sulfuric acid, sulfur dioxide, and oxygen at up to about 830 {sup o}C and 3.6 MPa. In Section III , aqueous, non-aqueous, and gaseous phases, at up to 310 {sup o}C and 2.2 MPa, ...
A structurally conserved element, the trigger loop, has been suggested to play a key role in substrate selection and catalysis of RNA polymerase II (pol II) transcription elongation. Recently resolved...Full Text Available
The insulin/IGF-1 signaling (IIS) pathway is a conserved regulator of longevity, development, and metabolism. In Caenorhabditis elegans IIS involves activation of DAF-2 (insulin/IGF-1...Full Text Available
DNA from the peripheral blood mononuclear cells of 17 different individuals infected with human T-cell lymphoma/leukemia virus type II (HTLV-II) was successfully amplified by the polymerase chain reaction...Full Text Available
A systematic study for the materials design of III-V and II-VI compound-based ferromagnetic diluted magnetic semiconductors is given based on ab initio calculations within the local spin density approximation. The electronic structures of 3d-transition-metal-atom-doped GaN and Mn-doped InN, InP, InAs, InSb, GaN, GaP, GaAs, GaSb, AlN, AlP, AlAs and AlSb were calculated by the Korringa-Kohn-Rostoker method combined with the coherent potential approximation. It is found that the ferromagnetic ground states are readily achievable in V-, Cr- or Mn-doped GaN without any additional carrier doping treatments, and that InN is the most promising candidate for high-T_C ferromagnet. A simple explanation of the systematic behavior of the magnetic states in III-V and II-VI compound-based diluted magnetic semiconductors is also given. It is also shown that V or Cr-doped ZnS, ZnSe, and ZnTe are ferromagnetic without p- or n-type doping ...
Full text: Based on experience with nuclear material confiscated in Hungary from illicit trafficking activities in the nineties it has been decided that traditional gamma-spectrometry should be complemented by destructive analytical techniques. The 17/1996 (I. 31.) Korm. Governmental Decree delegated the identification, categorization and characterization tasks to the Institute of Isotopes, Budapest. Routine gamma-spectrometric methods have been further developed aiming at the i) age (production date) determination of seized samples and complete (nondismountable) uranium-bearing items (such as fresh fuel bundles and fission chambers) by HRGS technique, ii) improvement of measurement accuracy and reliability. Starting in 2005 mass spectrometry (ICP-SFMS) and scanning electron microscopy have been implemented to characterize nuclear samples in more detail and to analyze environmental samples both for isotopic and elemental composition focusing on ...
The results of this research centered on the experimental studies of a single superconducting persistent current qubit, the implementation of type-II algorithms using these qubits, and the proposal for adiabatic quantum computing using these qubits. The m...
The in vivo photochemical activity of photosystem II was inferred from modulated chlorophyll fluorescence and photoacoustic measurements in intact leaves of several plant species (Lycopersicon...Full Text Available
Woolfolk, C. A. (University of Washington, Seattle). Reduction of inorganic compounds with molecular hydrogen by Micrococcus lactilyticus. II. Stoichiometry with inorganic...Full Text Available
... and high-quality photospheric-phase Type II SN spectra to constrain core- collapse SN explosions, massive star evolution, and distances in the Universe ...
This document describes payload control at LLNL to ensure that all shipments of CH-TRU waste in the TRUPACT-II (Transuranic Package Transporter-II) meet the requirements of the TRUPACT-II SARP (safety report for packaging). This document also provides specific instructions for the selection of authorized payloads once individual payload containers are qualified for transport. The physical assembly of the qualified payload and operating procedures for the use of the TRUPACT-II, including loading and unloading operations, are described in HWM Procedure No. 204, based on the information in the TRUPACT-II SARP. The LLNL TRAMPAC, along with the TRUPACT-II operating procedures contained in HWM Procedure No. 204, meet the documentation needs for the use of the TRUPACT-II at LLNL. Table 14-1 provides a summary of the LLNL waste generation and ...
Biosorption using activated sludge biomass (ASB) as a potentially sustainable technology for the treatment of wastewater containing different metal ions (Cd(II), Pb(II) and Zn(II)) was investigated. ASB metal uptake clearly competed with protons consumed by microbial biomass compared with control tests with non-activated sludge biomass. Biosorption tests confirmed maximum exchange between metal ions and protons at pH 2.0-4.5. It was revealed by the study that the amount of metal ions released from the biomass increased with biomass sludge concentration. The result showed that maximum absorption of metal ions was observed for Cd(II) at pH 3.5, Pb(II) at pH 4.0, and pH 4.5 for Zn(II) ions. The maximum absorption capacities of ASB for Cd(II), Pb(II) and Zn(II) were determined to be 59.3, 68.5 and 86.5%, ...
Research highlights: {yields} The use of resonant photoemission in its 'core-hole clock' expression for the study of the dynamical charge transfer across hybrid organic-inorganic interfaces and for the intermolecular charge transfer in the bulk of organic thin films is reviewed. {yields} The electronic coupling to the substrate and the efficiency of charge transport across hybrid interfaces is different for individual electronic subsystems of the molecular adsorbate. {yields} The intermolecular charge transfer in the bulk of discotic liquid crystals occurs on the order of a few femtoseconds and is faster than expected from the macroscopic charge transport characteristics of the material. -- Abstract: The focus of this brief review is the use of resonant photoemission in its 'core-hole clock' expression for the study of two important problems relevant for the field of organic electronics: the dynamical charge transfer across ...
Apart from the vulnerability implied by the START II treaty, it will bear the burden of the general political opposition to the Yeltsin administration. START II will be seen as part of an overall Yeltsin-Andrei Kozyrev foreign policy that is under fire for selling out Russian national interests in Yugoslavia, the Persian Gulf, and elsewhere. This article discusses public opinion concerning START II, the cost of its implementation, and the general purpose of the treaty.
The upgraded CDF II detector has collected first data during the initial operation of the Tevatron accelerator in Run II. The simulation of the CDF electromagnetic and hadronic central and upgraded plug (forward) calorimeter is based on the Gflash calorimeter parameterization package used within the GEANT based detector simulation of the Run II CDF detector. We present the results of tuning the central and plug calorimeter response to test beam data.
PRESTO-II is a computer code developed to evaluate possible health effects from shallow land disposal of low level radioactive wastes. PRESTO-PREP is a data preprocessor that has been developed to expedite the formation of input data sets for PRESTO-II. PRESTO-PREP utilizes a library of nuclide and risk-specific data. Given an initial waste inventory, the code creates the radionuclide portion of the associated input data set for PRESTO-II. 2 references.
The purpose of this paper is to describe the embedded computer systems approach taken at Experimental Breeder Reactor II (EBR-II) for non-safety related systems. The hardware and software structures for typical embedded systems are presented The embedded systems development process is described. Three examples are given which illustrate typical embedded computer applications in EBR-II.
Angiotensin II (Ang II) is a key proapoptotic factor in fibrotic tissue diseases. However, the mechanism of Ang-II-induced cell death in endothelial cells has not been previously elucidated....Full Text Available
1. Contest rules The European Space Agency (ESA) is launching a public competition to find the most suitable names for its four Cluster II space weather satellites. The quartet, which are currently known as flight models 5, 6, 7 and 8, are scheduled for launch from Baikonur Space Centre in Kazakhstan in June and July 2000. Professor Roger Bonnet, ESA Director of Science Programme, announced the competition for the first time to the European Delegations on the occasion of the Science Programme Committee (SPC) meeting held in Paris on 21-22 February 2000. The competition is open to people of all the ESA member states (*). Each entry should include a set of FOUR names (places, people, or things from history, mythology, or fiction, but NOT living persons). Contestants should also describe in a few sentences why their chosen names would be appropriate for the four Cluster II satellites. The winners will be those which are considered most suitable ...
Carbalkoxylation of vinyl electrophiles was investigated using platinum complexes. This reaction occurs in two steps: (a) carbonyl insertion of {sigma}-vinyl Pt(II) halides and (b) alcoholysis of vinylic acyl Pt(II) complexes. Alcoholysis of vinylic acyl Pt(II) triflate complexes is investigated kinetically. Vinylic acyl Pt(II) complexes were isolated and characterized. 51 refs., 5 figs., 6 tabs.
Background: EGFR (epidermal growth factor receptor) and VEGF (vascular endothelial growth factor) inhibitors confer clinical benefit in metastatic colorectal cancer when combined with chemotherapy. An emerging strategy to improve outcomes in rectal cancer is to integrate biologically active, targeted agents as triple therapy into chemoradiation protocols. Material and methods: cetuximab and bevacizumab have now been incorporated into phase I-II studies of preoperative chemoradiation therapy (CRT) for rectal cancer. The rationale of these combinations, early efficacy and toxicity data, and possible molecular predictors for tumor response are reviewed. Computerized bibliographic searches of Pubmed were supplemented with hand searches of reference lists and abstracts of ASCO and ASTRO meetings. Results: the combination of cetuximab and CRT can be safely applied without dose compromises of the respective treatment components. Disappointingly low ...
(Materials and Methods) (I) VX/sub 2/ carcinoma was transplanted to the rabbit tibia, sup(99m)Tc-MDP was intravenously injected when bone destruction was radiologically seen. Preoperative scintigraphs, postoperative one of the resected tibia and fibra and scintigraphs of sliced tumor were compared with each other. Tissue fragments were collected from the sliced tumor, and RI was measured to compare concentration rates at different parts together with histological investigations. (II) Tetracycline was given to the rabbit of Experiment (I) to compare with the concentration of sup(99m)Tc-MDP. (III) Microautoradiography method was done on the experimental animals for investigation of the concentration of sup(99m)Tc-MDP. (Results) (I) Localization of sup(99m)Tc-MDP was increased at the sites of tumorous bone formation, of reactive bone formation at tumor edges, and of cartilage calcification, with little concentration at tumor cells or necrotic ...
Background and purpose: A series of phase I/II clinical trials are being initiated in several UK centres to explore the use of dose-escalated schedules for the treatment of non-small cell lung cancer (NSCLC). Among them the IDEAL-CRT trial (ISRCTN12155469) will investigate the introduction of individualised 'isotoxic' treatment schedules based on the relative mean lung normalised total dose (rNTDmean), an estimator related to lung toxicity. Since treatment planning will be performed using different treatment planning systems (TPSs), for the quality assurance of the trial we have carried out work to quantify the influence of dose calculation algorithms based on the determination of rNTDmean and on the choice of individualised prescription doses. Material and methods: Twenty-five patient plans with stage I, II and III NSCLC were calculated, with the same prescription dose, using the Adaptive Convolve (AC) and Collapsed Cone ...
Background and purpose: In order to investigate the feasibility, toxicity and antitumor efficacy of hyperfractionated radiation therapy, 37 adult patients with incompletely resected supratentorial low-grade glioma were entered into a phase II study. Materials and methods: The radiation therapy dose was 55 Gy in 50 fractions in 25 treatment days over 5 weeks to the tumor plus a 2-cm margin, with an additional 17.6 Gy given in 16 fractions in 8 treatment days over 1.5 weeks to the tumor plus a 1-cm margin, using 1.1 Gy b.i.d. fractionation with a 6 h interfraction interval. The total tumor dose was 72.6 Gy in 66 fractions in 33 treatment days over 6.5 weeks. Results: The median survival time (MST) for all 37 patients has not yet been attained, while 5- and 7-year survival rates were 75% and 69%, respectively. The median time to tumor progression (MTP) has also not yet been attained, while 5- and 7-year progression-free survival (PFS) rates were ...
Twenty autopsy cases with 2009 pandemic influenza A (2009 H1N1) virus infection, performed between August 2009 and February 2010, were histopathologically analyzed. Hematoxylin-eosin staining, immunohistochemistry for type A influenza nucleoprotein antigen, and real-time reverse transcription-PCR assay for viral RNA were performed on formalin-fixed and paraffin-embedded specimens. In addition, the D222G amino acid substitution in influenza virus hemagglutinin, which binds to specific cell receptors, was analyzed in formalin-fixed and paraffin-embedded trachea and lung sections by direct sequencing of PCR-amplified products. There were several histopathological patterns in the lung according to the most remarkable findings in each case: acute diffuse alveolar damage (DAD) with a hyaline membrane (four cases), organized DAD (one case), acute massive intra-alveolar edema with variable degrees of hemorrhage (three cases), neutrophilic bronchopneumonia (five cases) and tracheobronchitis ...
The electronic structure and properties of the cubic Laves phase (C15) compounds ZrZn_2 and ZrV_2 have been determined using our all-electron full-potential linearized-augmented-plane-wave (FLAPW) method for bulk solids. The computations were performed in two stages: (i) self-consistent warped muffin tin and (ii) self-consistent full potential. Spin-orbit coupling was included after either stage. The effects of the inclusion of the nonspherical terms inside the muffin tins on the eigenvalues is found to be small (of order 1 mRy). However, due to the fact that some of the bands near the Fermi level are flat, this effect leads to a much higher value of the density of states at E/sub F/ in ZnZr_2. The most important difference between the materials ZrZn_2 and ZrV_2 is the position of the d bands derived from the Zr and V atoms. Consequently, these materials have completely different Fermi surfaces. We have investigated the ...
The electronic structure and properties of the cubic Laves phase (C15) compounds ZrZn/sub 2/ and ZrV/sub 2/ have been determined using our all-electron full-potential linearized-augmented-plane-wave (FLAPW) method for bulk solids. The computations were performed in two stages: (i) self-consistent warped muffin tin and (ii) self-consistent full potential. Spin-orbit coupling was included after either stage. The effects of the inclusion of the nonspherical terms inside the muffin tins on the eigenvalues is found to be small (of order 1 mRy). However, due to the fact that some of the bands near the Fermi level are flat, this effect leads to a much higher value of the density of states at E/sub F/ in ZnZr/sub 2/. The most important difference between the materials ZrZn/sub 2/ and ZrV/sub 2/ is the position of the d bands derived from the Zr and V atoms. Consequently, these materials have completely different Fermi surfaces. We ...
The general principles of Cu(II) binding to algal waste from agar extraction, composite material and algae Gelidium, and different modelling approaches, are discussed. FTIR analyses provided a detailed description of the possible binding groups present in the biosorbents, as carboxylic groups (D-glucuronic and pyruvic acids), hydroxyl groups (cellulose, agar and floridean starch) and sulfonate groups (sulphated galactans). Potentiometric acid-base titrations showed a heterogeneous distribution of two major binding groups, carboxyl and hydroxyl, following the quasi-Gaussian affinity constant distribution suggested by Sips, which permitted to estimate the maximum amount of acid functional groups (0.36, 0.25 and 0.1 mmol g{sup -1}) and proton binding parameters (pK{sup '}{sub H}=5.0,5.3and4.4;m{sub H} = 0.43, 0.37, 0.33), respectively for algae Gelidium, algal waste and composite material. A non-ideal, semi-empirical, ...
A geochemical survey to assess and evaluate the Devonian oil shale resources of north Alabama, northwest Georgia, and south-central Tennessee has been performed. Information is provided on the location and extent of the more favorable kerogen-bearing Devonian shale, oil and uranium content of the shale, trace metal and standard rock analyses for shale, data on the physical properties of the shale rock, mineralogy of the shale, chemical properties of the oil, and other pertinent data deemed necessary for resource development. The results indicate that the oil yield from areas underlain by Chattanooga Shale can be divided into areas having greater than 7 g/t and areas having less than 7 g/t. In general, the oil yield by Fischer assay of samples from the folded Appalachian Valley and Ridge and the Appalachian Plateaus provinces is poor, all having less than 5 g/t and most samples closer to 0 g/t. The extreme variance of Fischer assay values in the Chattanooga Shale could be the result of ...
The manual was prepared for State and local government officials, local emergency planning committee (LEPCs), and other community groups that want to make Title III work. It is intended as a practical guide for those who have little or no previous experience in the field of communication, whose time must be snatched from home and office, and whose resources are limited. The manual has three major sections: Part I discusses planning, which is vital to the success of a communication program; Part II suggests ways to get and keep people involved, especially important because Title III affects so many different sectors of the community; Part III, a how-to-do-it section, talks about specific tasks, such as giving a speech or writing a press release. Appendices include a detailed explanation of the law, a glossary, a list of recent studies related to Title III communications, a list of educational materials, and a list of State contacts.
In 1972 a consortium consisting of Gebruder Sulzer A.G., Winterthur and EVT, Energie- und Verfahrenstechnik G.m.b.H., Stuttgart, was awarded the contract by HBR, Hochtemperatur Reaktorbau G.m.b.H., Koln/Mannheim, for the design, manufacture and installation of the 6 steam generator units for the prototype 300 MWe Thorium High Temperature Reactor (THTR) at Schmehausen, Germany. The design and manufacture of the 6 units is done by Sulzer; installation of the units as well as the manufacture of the external pipework and headers is done by EVT. The units are built under semiclean conditions in a special workshop at CCM-Sulzer in mantes, France. This workshop had been used previously for the manufacture of the steam generators for the nuclear power plants St. Laurent I, II, Vandellos (500 Mwe each) and EL-4 (70 Mwe). The present paper defines the operating conditions and the chemical composition of the materials used, including Alloy 800. Reasons ...
A computational model has been developed to calculate the potential and current distributions in the electrolyte phase and on the electrode surface for a system in which a part of the anode is passivated while the rest remains in the active dissolution state. The computation employs the finite element method allied with a boundary variation and a trial and error technique. From the obtained distributions, the location of the boundary between the active and passive regions on the anode can be predicted. In the case of a crevice, this means that a critical distance into the crevice exists beyond which active corrosion (crevice corrosion) takes place. In addition to the active/passive behavior of the material, solution conductivity, applied potential at the sample's outer surface, crevice gap and depth dimensions, and passive current density influence this critical distance to different degrees. The developed software package may also be used for (i) ...
Material related to routine as well as sensitive aspects of parent/day care center relationships is presented in this training module, one of a series providing staff development information for programs operated for dependents of military personnel. The module offers a brief discussion of ways caregivers can help parents feel at ease about leaving their children in child care and presents a set of multiple-choice skill-building exercises for effectively working with parents. Exercises focus on various topics, including how parents can be approached when their child may have a health problem, when child abuse or neglect is suspected, and when parental cooperation is needed to stop a child's undesirable or disruptive behavior. Exercises are also devoted to the questions of whether or not caregivers should act as advisors to parents or tell parents about their child's behavior at the center. Concluding exercises indicate how caregivers can handle parent requests for ...
A study has been made of the precipitation and growth processes which occur during cooling from solution treatment and under isothermal hold conditions in a magnesia-partially-stabilized zirconia alloy. Three types of precipitate have been identified which develop during cooling or during isothermal hold treatments just above and below the eutectoid temperature. These precipitate forms are termed (i) primary, (ii) large random, and (iii) secondary. Further precipitation, slow growth of existing precipitates, and subeutectoid decomposition result when an additional 1100/sup 0/C aging treatment is given to the previously cooled material. It is shown that type (iii) secondary precipitates from rapidly within the temperature range of 1300/sup 0/ to 1375/sup 0/C. The secondary precipitates are largely responsible for the improved room-temperature strength properties of the heat-treated samples. The formation and effects on mechanical properties of ...
A study has been made of the precipitation and growth processes which occur during cooling from solution treatment and under isothermal hold conditions in a magnesia-partially-stabilized zirconia alloy. Three types of precipitate have been identified which develop during cooling or during isothermal hold treatments just above and below the eutectoid temperature. These precipitate forms are termed (i) primary, (ii) large random, and (iii) secondary. Further precipitation, slow growth of existing precipitates, and subeutectoid decomposition result when an additional 1100"0C aging treatment is given to the previously cooled material. It is shown that type (iii) secondary precipitates from rapidly within the temperature range of 1300"0 to 1375"0C. The secondary precipitates are largely responsible for the improved room-temperature strength properties of the heat-treated samples. The formation and effects on mechanical properties of each type of ...
Argentina has two operating PHWR nuclear power plants. Atucha I NPP is a pressure vessel type heavy water reactor of 360 MW e with 25 years of operation and Embalse NPP is a pressure tube type CANDU-600 reactor of 640 MW e. Atucha II, a third plant of 600 MW e of the pressure vessel type similar to Atucha I, is being constructed. NASA (Nucleoelectrica Argentina S.A.) currently operates both nuclear power plants. The National Atomic Energy Commission (Comision Nacional de Energia Atomica - CNEA) provides operational support to the plants, including research and development assistance, and actual technical services and maintenance work in different areas. The Chemistry Department, formerly the Reactor Chemistry Department has carried out project and support activities to the plants during the past 20 years. The aim of this work is to describe the present organization and the activities in reactor chemistry of the Chemistry Department. In particular, the projects to ...
This research report discusses the radiation hardening of a commercially available mobile robot, the REMOTEC ANDROS. This hardening effort is culminating in the availability of a megarad hardened mobile platform to access areas in nuclear facilities with extremely high levels of radiation (0.1 to 1 Mrad). These radiation levels may be encountered both during routine repair and monitoring activities and accident situations. The project has completed a phase-I U.S. Department of Energy Small Business Innovative Research contract and is now in a phase-II effort with completion scheduled in early 1995. The research involves the evaluation of the material and electrical components of an ANDROS robot to determine the anticipated radiation hardness of the current production version and evaluation of the components that must be replaced or modified to harden the system to higher radiation levels. The work being reported is based on an evaluation of the ...
The weldability and high temperature strength properties of tungsten-inert-gas (TIG) weldments of Hastelloy alloy XR were investigated by using two different heats of filler metals; the first (HXRF1) was designed on the basis of multiple regression analysis; the second (HXRF2) was the reference material. Bend tests, the FISCO cracking test and optical metallography were used to evaluate weldability. Tensile and creep tests were performed at 900deg C to evaluate high temperature strength properties. The results of weldability tests for both alloys showed good performance. The tensile properties of the weldments were remarkably improved in particular with respect to high temperature ductility. The creep rupture strength in the weldments made with alloy-designed HXRF1 was much higher than those of the Hastelloy alloy XR-II base metal with a higher B content. Furthermore, the creep properties were stable with respect to variations in welding ...
The weldability and high temperature strength properties of tungsten-inert-gas (TIG) weldments of Hastelloy alloy XR were investigated by using two different heats of filler metals; the first (HXRF1) was designed on the basis of multiple regression analysis; the second (HXRF2) was the reference material. Bend tests, the FISCO cracking test and optical metallography were used to evaluate weldability. Tensile and creep tests were performed at 900deg C to evaluate high temperature strength properties. The results of weldability tests for both alloys showed good performance. The tensile properties of the weldments were remarkably improved in particular with respect to high temperature ductility. The creep rupture strength in the weldments made with alloy-designed HXRF1 was much higher than those of the Hastelloy alloy XR-II base metal with a higher B content. Furthermore, the creep properties were stable with respect to variations in welding ...
The overall objective of the study in this report was to gather data on waste management technologies to allow comparison of various alternatives for managing municipal solid waste (MSW). The specific objectives of the study were to: 1. Compile detailed data for existing waste management technologies on costs, environmental releases, energy requirements and production, and coproducts such as recycled materials and compost. Identify missing information necessary to make energy, economic, and environmental comparisons of various MSW management technologies, and define needed research that could enhance the usefulness of the technology. 3. Develop a data base that can be used to identify the technology that best meets specific criteria defined by a user of the data base. Volume I contains the report text. Volume II contains supporting exhibits. Volumes III through X are appendices, each addressing a specific MSW management technology. Volumes XI ...
Experience at SRS, ORNL, BNL, and Georgia Institute of Technology involving irradiated aluminum clad fuel and target elements, as well as studies of non-irradiated aluminum indicate that some types of aluminum assemblies can be kept in a continually well-deionized water atmosphere for up to 25 years without problems. SRS experience ranges from 2.75 years for the L-1.1 charge kept in deionized D[sub 2]O[sup 1] to greater than 10 years for assemblies stored in the Receiving Basin for Off-site Fuel (RBOF)[sup 2]. Experience at Georgia Institute of Technology reactor in Atlanta yielded the longest value of 25 years without problems. The common denominators in all of the reports is that the water is continually deionized to approximately 2 M[Omega] (2 [times] 10[sup 6]ohms) resistivity and the containers for the water are stainless steel or other non-porous material. This resistivity value is equivalent to a value of 0.5 micromhos or microSiemens conductivity and is ...
Experience at SRS, ORNL, BNL, and Georgia Institute of Technology involving irradiated aluminum clad fuel and target elements, as well as studies of non-irradiated aluminum indicate that some types of aluminum assemblies can be kept in a continually well-deionized water atmosphere for up to 25 years without problems. SRS experience ranges from 2.75 years for the L-1.1 charge kept in deionized D{sub 2}O{sup 1} to greater than 10 years for assemblies stored in the Receiving Basin for Off-site Fuel (RBOF){sup 2}. Experience at Georgia Institute of Technology reactor in Atlanta yielded the longest value of 25 years without problems. The common denominators in all of the reports is that the water is continually deionized to approximately 2 M{Omega} (2 {times} 10{sup 6}ohms) resistivity and the containers for the water are stainless steel or other non-porous material. This resistivity value is equivalent to a value of 0.5 micromhos or microSiemens conductivity and is ...
The subfornical organ is a major receptor area for one of the principal stimuli of thirst, the octapeptide, angiotensin II. In conscious water-sated rats, the authors examined the effects of intravenous infusion of angiotensin II on the rate of glucose utilization in the subfornical organ and in structures anatomically and functionally connected with it. Angiotensin II produced pressor and drinking responses and increased glucose utilization selectively in the subfornical organ and pituitary neural lobe and in no other brain structure. Treatment with the angiotensin II antagonist, sar1-leu8-angiotensin II, before intravenous administration of angiotensin II prevented metabolic stimulation of the subfornical organ and neural lobe. Captopril, an inhibitor of angiotensin-converting enzyme, reduced subfornical organ glucose metabolism to a level similar to that ...
Adsorptive removal of Pb(II) ions from aqueous solution onto a non-activated charcoal (CC) of oak wood origin was studied in comparison with an activated carbon of coal origin. The adsorption capacity for Pb(II) of the non-activated charcoal increased significantly with deceasing particle diameter, whereas the activated carbon (AC) exhibited approximately constant capacity for Pb(II) adsorption as a function of particle size. Adsorption to the ashes prepared from the non-activated charcoal and the activated carbon was also investigated to examine the role of mineral ash. Although the ash from the activated carbon did not show any Pb(II) adsorption, the ash from the charcoal was very effective for Pb(II) adsorption. Furthermore, Pb(II) was hardly adsorbed when the ash was removed from the non-activated charcoal by acid treatment. Based on the results, the ...
The isotherms, kinetics and thermodynamics of Cd(II), Zn(II) and Pb(II) biosorption by Penicillium simplicissimum were investigated in a batch system. The effects of pH, initial metal ions concentration, biomass dose, contact time, temperature and co-ions on the biosorption were studied. Adsorption data were well described by both the Redlich-Peterson and Langmuir model. Chemical ion-exchange was found to be an important process based on free energy value from Dubini-Radushkevich isotherm for all metal ions. The results of the kinetic studies of all metal ions at different temperature showed that the rate of adsorption followed the pseudo second-order kinetics well. The thermodynamics constants {delta}G{sup o}, {delta}H{sup o} and {delta}S{sup o} of the adsorption process showed that biosorption of Cd(II), Zn(II) and Pb(II) ions on Penicillium simplicissimum ...
In this paper, multilayer oxide nanorods were deposited in the nanopores of anodic aluminum oxide (AAO) via solution infiltration followed by heat treatment. The nanorods have a core-shell structure. First, the shell (nanotube) with the thickness of about 40nm was made of TiO"2 through the hydrolysis of (NH"4)"2TiF"6. Second, silver nanoparticles with the diameter of about 3nm were added into the TiO"2 layer through thermal decomposition of AgNO"3 at elevated temperatures. Then, cylindrical cores (nanorods) of CoO and ZnO with 200nm diameter were prepared, respectively. Scanning electron microscopy (SEM) and transmission electron microscopy (TEM) were used to characterize the structure and composition of the nanorods. UV-vis light absorption measurements in the wavelength range from 350 to...
Abstract A series of polypropylene carbonate (PPC)/ZnO nanocomposite films with different ZnO contents were prepared via a solution blending method. The morphological structures, thermal properties, oxygen permeability, water sorption, and antibacterial properties of the films were investigated as a function of ZnO concentration. While all of the composite films with less than 5 wt % ZnO exhibited good dispersion of ZnO in the PPC matrix, FTIR and SEM results revealed that solution blending did not lead to a strong interaction between PPC and unmodified ZnO. As such, poor dispersion was induced in the composite films with a high ZnO content. By incorporating inorganic ZnO filler nanoparticles, the diffusion coefficient, water uptake in equilibrium, and oxygen permeability decreased as the ...
Several compatibilising systems were added to high-density polyethylene (HDPE) and polyamide 6 (PA6) blends in the presence of an organically modified montmorillonite (OMM). All the blends were prepared by using a co-rotating twin-screw extruder and characterized by SEM, TEM and XRD analyses. In addition, the rheological behaviour and the mechanical properties - tensile and impact - were evaluated. The presence of OMM affects the dimensions of the polymeric phases in the blend but not their mutual adhesion, granted only by the compatibilisers. TEM, SEM and XRD analyses indicated that there is a strict correlation between the compatibilisation level and the final interlayer distance achieved by OMM. Even if some filled compatibilised blends showed a fairly good morphology - in terms of phas...
A poly(ether urethane) (PEUR)/poly(ethylene oxide) (PEO)/SiO2 based nanocomposite polymer is prepared and employed in the construction of high efficiency all-solid-state dye-sensitized nanocrystalline solar cells. The introduction of low-molecular weight PEUR prepolymer into PEO electrolyte has greatly enhance the electrolyte performance by both improving the interfacial contact properties of electrode/electrolyte and decreasing the PEO crystallization, which were confirmed by XRD and SEM characteristics. The effects of polymer composition, nano SiO2 content on the ionic conductivity and I3- ions diffusion of polymer-blend electrolyte are investigated. The optimized composition yields an energy conversion efficiency of 3.71% under irradiation by white light (100 mW cm-2).
Yb3+?Tm3+ codoped tellurite glasses containing silver nanoparticles (NPs) were synthesized and characterized using transmission electron microscopy and optical techniques. The samples? composition and the nucleation of NPs were investigated using electron diffraction and energy dispersive spectroscopy. For the optical experiments, the samples were excited using a diode laser operating at 980?nm, in resonance with the Yb3+ transition 2F7/2?2F5/2. Photoluminescence (PL) bands corresponding to Tm3+ transitions were observed at 480, 650, and 800?nm due to the Yb3+? Tm3+ energy transfer. PL enhancement was achieved by heat-treatment of the samples at 325?C during different time intervals. The growth of the PL bands correlates with the increase of the silver NPs concentration. The relevant mecha...
Emeraldine base (EB) polymer?ZnO nanoparticles composite films has been synthesized by solution casting technique on ITO-coated glass substrate and characterized by XRD, FTIR and TEM for their structure and morphology. Dielectric behaviour of these composite films has been investigated in the very low frequency region to medium frequency region (1?kHz?1?MHz). The dielectric constant of the composite with 30% nanoparticles is almost one-tenth of the pure EB. The dielectric value becomes constant in the frequency region greater than 400?kHz. The change in dielectric behaviour of the composite is explained on the basis of multilayered interface formed between the ZnO nanoparticles and emeraldine chains. Nanoparticles have high energy surface which is responsible for the decrease of free volum...
An exact cosmological solution of Einstein's equations which has time-dependent rotation is presented. The t-constant sections are of Bianchi type II. The source of this geometry is a fluid which has not been thermalized. (Author).
Exposure of albumin to Cu(II) (10-100 microM) and ascorbate (0.1-2 mM) results in extensive molecular modifications, indicated by decreased fluorescence and chain breaks. The rate of utilization of...Full Text Available
ObjectivesThe updated Rome III criteria for pediatric functional gastrointestinal disorders (FGIDs) include new FGID categories and changes to the Rome II criteria...Full Text Available
Interleukin 2 (IL-2) and B-cell growth factors I and II (BCGF I and BCGF II) are lymphokines produced by T cells that play a major role in T- and B-cell cooperation. Peripheral blood lymphocytes from...Full Text Available
In this article are presented main results on electric potential investigations in stellarator/torsatron TJ-II and tokamak T-10 in a comparable regimes of device operation.
Aminopeptidase II, one of the two major aminopeptidases in the giant alga Chara australis, was partially purified. Its molecular weight was estimated to be about 80,000 by gel permeation...Full Text Available
New palladium(II) and platinum(II) complexes of saccharinate (sac), trans-[Pd(py)"2(sac)"2] (1), cis-[Pt(py)"2(sac)"2] (2), trans-[Pd(3-acpy)"2(sac)"2] (3) and cis-[Pt(3-acpy)"2(sac)"2] (4) (py=pyridine and 3-acpy=3-acetylpyridine) have been synthesized. Elemental analysis, UV-Vis, IR, NMR and TG/DTA characterizations have been carried out. The structures of 1-4 were determined by X-ray diffraction. The palladium(II) and platinum(II) ions are coordinated by two N-bonded sac ligands, and two nitrogen atoms of py or 3-acpy, forming a distorted square-planar geometry. The palladium(II) complexes (1 and 3) are trans isomers, while the platinum(II) complexes (2 and 4) are cis isomers. The mononuclear species in the solid state are connected by weak intermolecular C-H...O hydrogen bonds, C-H...@...
BackgroundThe binding of peptide fragments of antigens to class II MHC is a crucial step in initiating a helper T cell immune response. The identification of such peptide epitopes...Full Text Available
The aim of this article was to investigate the interactions of metal cations in aqueous solutions with the biomass of the freshwater macroalga Vaucheria sp. This problem is important when elaborating new applications of biosorption, e.g. the production of mineral feed additives for livestock from the biomass of algae enriched with microelement ions. Potentiometric titration was applied as a quick and cheap screening test to search for new efficient biosorbents. It revealed a variety of functional groups capable of cation exchange on the macroalgal surface, including carboxyl, phosphate, hydroxyl or amino groups. Fourier transform infrared spectroscopy on natural and chromium-loaded Vaucheria sp. confirmed that carboxyl groups played a dominant role in the biosorption. The study also showed that Ca(II), Na(I), K(I), and Mg(II) ions were released from the biomass after biosorption of Cu(II), Mn(II), ...
BackgroundPromoter region plays an important role in determining where the transcription of a particular gene should be initiated. Computational prediction of eukaryotic Pol II promoter...Full Text Available
Rotazyme II, which is a shorter version of Rotazyme (less than 3 h), was compared with electron microscopy and Rotazyme for sensitivity and specificity on 229 human stool specimens. Compared with electron...Full Text Available
The biosorption of lead (II) and copper (II) ions, single component and binary systems, by dried P. putida was investigated in a batch system. The effects of initial pH, temperature, initial single and binary mixture concentrations on the biosorption kinetics and equilibrium uptake of each component, both single and binary mixtures were investigated. The bacterial biomass exhibited the highest single and binary lead (II) and copper (II) ions uptake capacity at 25 and 30 deg. C, respectively, the initial pH value of 5.5 and at the initial metal ions concentration of 100 mg dm{sup -3}. The Freundlich and Langmuir adsorption models were used for the mathematical description of the biosorption equilibrium and isotherm constants were evaluated at different temperatures. Adsorption data were well described by the Langmuir model, although they could be modeled by the Freundlich equation. The thermodynamics ...
BackgroundPerfluorocarbons (PFC) are used to improve gas exchange in diseased lungs. PFC have been shown to affect various cell types. Thus, effects on alveolar type II (ATII) cells...Full Text Available
ATP-binding cassette A3 (ABCA3) is a lipid transport protein required for synthesis and storage of pulmonary surfactant in type II cells in the alveoli. Abca3 was conditionally deleted...Full Text Available
Cytokinesis in animal and fungal cells utilizes a contractile actomyosin ring (AMR). However, how myosin II is targeted to the division site and promotes AMR assembly, and how the AMR coordinates with...Full Text Available
Anaerobic reactions of Rhus vernicifera laccase and its type-2 copper-depleted derivatives with hexacyanoferrate(II) were investigated by absorption and e.s.r. spectroscopy. When native laccase was...Full Text Available
Photobilirubin II, a stereoisomer of bilirubin, binds to human serum albumin at a single binding site (K = 2.2 x 10(6)M-1), presumably the high-affinity bilirubin-binding site. Binding in the secondary...Full Text Available
The identification of MHC class II restricted peptide epitopes is an important goal in immunological research. A number of computational tools have been developed for this purpose, but there is a lack...Full Text Available
ii) Flammability: (iii) A capacity to oxidise: (iv) Corrosiveness: (v) Toxicity (including chronic ...an explosion or fire: (d) For substances with corrosive properties: (i) To reduce the ...likelihood of any unintended corrosion:(ii) To control the adverse effects of any corrosion:
A bottom-up approach is used here to combine carbon nanotubes synthesized by CVD and organically capped platinum nanoparticles electrocatalyst exhibiting a direct electrochemical activity towards oxygen reduction. Both nano-objects are handled in liquid suspension and are associated together in a controlled way. The nanocomposite liquid dispersions can be precisely controlled in terms of platinum nanoparticles to carbon nanotubes weight ratios (NP/NT) which correspond to different coverages of nanotubes by nanoparticles. Electrodes with low to ultra-low platinum loadings can then be prepared on porous fuel cell carbon supports by filtration. The direct electrochemical activity towards aqueous oxygen reduction reaction (ORR) of electrodes with platinum loadings ranging from about 1 to 60 {mu}g/cm{sup 2} is reported without any activation step in order to keep the features of the nanoparticles intact. Before that, we studied the responses obtained when impregnating ...
... Materials (PREM) Synopsis of Program: The objective of PREM is to enhance diversity in materials ... careers in materials research. The Partnerships for Research and Education in Materials (PREM ...
... Materials (PREM) Synopsis of Program: The objective of PREM is to enhance diversity in materials ... careers in materials research.The Partnerships for Research and Education in Materials (PREM ...
... Materials Research - Major Instrumentation Project (IMR-MIP) program in the Division of Materials ... for materials preparation and characterization essential for researchers studying materials in a ...
... Instrumentation for Materials Research (IMR) Division of Materials Research Synopsis of Program ... for Materials Research (IMR) program in the Division of Materials Research (DMR) is designed to ...
... Materials Development Program TECHNOLOGY EDUCATION INSTRUCTIONAL MATERIALS Elementary - High School ... of technology education materials through its Instructional Materials Development (IMD) program. The ...
... Screening Adjudication Monitoring Applicants of Information Behavior II I Conducting Investigations ... Applicants of Information Behavior Conducting ...
Titanate nanotubes were hydrothermally synthesized and their adsorption performances for lead(II) ion removal were studied. The results showed that titanate nanotubes ruptured in the adsorption process resulting in two distinct adsorption stages, thus achieving a maximum adsorption capacity of 3.752mmolg^-^1 of lead(II). Furthermore, it was found that the regeneration of titanate nanotubes loaded with the lead(II) ions can be readily achieved using the saturated EDTA disodium salt aqueous solution, thereby avoiding the trouble of disposal of adsorbent. The adsorption mechanism was also discussed in detail.
The interaction between N-donor adsorbates such as ammonia and pyridine with Cu(II)-exchanged montmorillonite, beidellite, flourohectorite into smectite clays has been studied by electron spin resonance. Cu(II) cations exchanged into smectites coordinate five ammonia or pyridine molecules in beidellite, four ammonia of pyridine molecules in hydroxyhectorite. Thus, the Cu(II) cations bound to the interior surfaces of these smectite clays constitute strong Lewis acid sites. 26 refs., 7 figs., 1 tab.
Time-temperature-precipitation diagrams have been established for two steels with 6% Mo, 21% Cr, 25% Ni, 0.14 and 0.19% N (Cronifer 1925 h Mo = 1.4529, UNS N 08925) and for one steel with 6% Mo, 20% Cr, 18% Ni and 0.21% N (UNS S 31 254). The corresponding time-temperature-sensitization diagrams (in accordance to SEP 1877/II) and time-temperature-pitting diagrams (testing in 6% FeCl{sub 3} solution) have been evaluated as well. Precipitation of intermetallics occurs rapidly especially in the range between 700 and 1000{sup 0}C. In case of the 18% Ni steel and the 25% Ni/0.14% N steel grain boundaries are covered to a large extent with precipitates after only 15 min at 850 or 950{sup 0}C. In case of the 25% Ni/0.19% N steel precipitation is considerably slower. Therefore, when welding according to established rules and recommendations, no deterioration of the corrosion resistance in the heat-affected zone is to be expected. Additionally, the steel with 25% Ni has an ...
The valence and spin-state distributions of Co ions and the complex structure of antiferromagnetic Ba_2Co_9O_1_4 have led to the suggestion that doped Ba_2Co_9O_1_4 compounds may be good thermoelectric materials. We have checked this suggestion by measuring the magnetic properties as well as the transport properties of nominal Ba_1_._9A_0_._1Co_9O_1_4 (A=La or Na). We show that although all compounds are indicated to be single phase by powder X-ray diffraction analysis, they are all p-type polaronic conductors with low mobile-hole concentrations. Magnetic-susceptibility data of the parent and La-doped compounds give evidence of a second magnetic phase with ferromagnetic order setting in below 215 K; but this second phase is not seen in the Na-doped sample. We conclude that the structure is stabilized by oxidation and that cation exolution from the Ba_2Co_9O_1_4 structure creates cation vacancies that oxidize the high-spin (HS) Co(II) to the ...
When exposure-calibrated ionization chambers are used to calibrate megavoltage X-ray and electron beam therapy machines, the calibration factor can be divided into a chamber-dependent and a chamber-independent component. Until recently, only the chamber-independent part, which has been derived theoretically, has been used; the chamber-dependent component has been ignored. Recent experimental and theoretical considerations, however, have indicated that the dependent component must be taken into account and can affect the calibration by as much as 4%. The calibration can change due to (i) the thickness of the chamber wall, (ii) the chamber wall composition, i.e. whether the chamber is constructed of air-equivalent material, or tissue- or water-equivalent material, and (iii) the size of the chamber changing the displacement factor. Theoretical and experimental evidence indicates that the third factor varies from approximately ...
When Silk fibre derived from Bombyx mori, a native biopolymer, was dissolved in highly concentrated neutral salts such as CaCl{sub 2}, the regenerated liquid silk, a gradually degraded peptide mixture of silk fibroin, could be obtained. The silk fibroin nanoparticles were prepared rapidly from the liquid silk by using water-miscible protonic and polar aprotonic organic solvents. The nanoparticles are insoluble but well dispersed and stable in aqueous solution and are globular particles with a range of 35-125 nm in diameter by means of TEM, SEM, AFM and laser sizer. Over one half of the {epsilon}-amino groups exist around the protein nanoparticles by using a trinitrobenzenesulfonic acid (TNBS) method. Raman spectra shows the tyrosine residues on the surface of the globules are more exposed than those on native silk fibers. The crystalline polymorph and conformation transition of the silk nanoparticles from random-coil and {alpha}-helix form (Silk I) into anti-parallel {beta}-sheet form ...
Proposals for use of Alloy 800 as a H.T.R. boiler material have prompted studies of its creep and high temperature fatigue properties in impure helium with comparative tests in air. In impure helium, as expected in a H.T.R., reactions of potential importance are selective oxidation (of chromium, aluminium and titanium) and possibly carburisation from carbon monoxide or methane. In air, general oxidation will occur, possibly accompanied by nitridation. The effects of these reactions will depend on specimen geometry and the nature of the deformation. Two important possibilities are: (i) that environment affects the structure and properties of a surface zone of material undegoing uniform deformation (this may modify creep rate and crack nucleation); and (ii) that environment affects behaviour of a small region (e.g. at the root of a notch or ahead of a crack) in a specimen undergoing non-uniform deformation (this will modify ...
The cost of liquid fuels from coal is a complex function of many factors, such as capital investment, cost of coal and labor cost. Furthermore, the cost will depend on geographical position, the size of the operation and the efficiency of the process. There is no single answer and case studies will have to be made to establish economics at different locations. In the following, the 1980 order-of-magnitude investment costs and operating costs for a coal liquefaction plant are estimated. For a Sasol II type of plant with the product output indicated earlier, the total capital cost is estimated at $4 billion in 1980 dollars. Capital cost accounts for approximately 50%, utilities and materials for 30%, and labor for 20% of the total cost. Given the market value of by-product ethylene ($175/t), tar products ($300/t), chemicals ($300/t), ammonia ($200/t) and sulfur ($25/t), the credit for by-products is $146 million per year. The cost of motor fuel ...
Organic materials released from energy-related activities could affect human health and the environment. To better assess possible impacts, we developed a model to predict the fate of spills or discharges of pollutants into flowing or static bodies of fresh water. A computer code, Aquatic Pathways Model (APM), was written to implement the model. The computer programs use compartmental analysis to simulate aquatic ecosystems. The APM estimates the concentrations of chemicals in fish tissue, water and sediment, and is therefore useful for assessing exposure to humans through aquatic pathways. The APM will consider any aquatic pathway for which the user has transport data. Additionally, APM will estimate transport rates from physical and chemical properties of chemicals between several key compartments. The major pathways considered are biodegradation, fish and sediment uptake, photolysis, and evaporation. The model has been implemented with parameters for ...
Non-first order (FO) kinetics models are of three types; second order (SO), general order (GO) and mixed order (MO). It is shown that all three of these have constraints in their energy level schemes and their applicable parameter values. In nature such restrictions are not expected to exist. The thermoluminescence (TL) glow peaks produced by these models shift their position and change their shape as the trap occupancies change. Such characteristics are very unlike those found in samples of real materials. In these models, in general, retrapping predominates over recombination. It is shown that the quasi-equilibrium (QE) assumption implied in the derivation of the TL equation of these models is quite valid, thus disproving earlier workers' conclusion that QE cannot be held under retrapping dominant conditions. However notwithstanding their validity, they suffer from the shortcomings as stated above and have certain lacunae. For example, the kinetic order ...
We report the of the existence of RV Tauri stars in the Large Magellanic Cloud (LMC). This class of variable star has hitherto been unidentified in the Magellanic Clouds. In light and color curve behavior the RV Tauri stars appear to be an extension of the Type II Cepheids to longer periods. A single period-luminosity-color relationship is seen to describe both the Type II Cepheids and the RV Tauri stars in the LMC.
Incorporation of /sup 32/P from (gamma-32P)ATP into tyrosine residues of the insulin-like growth factor (IGF)-II receptor was observed in a Triton X-100-insoluble fraction of rat adipocyte plasma membranes. IGF-II receptor phosphorylation proceeded to a stoichiometry of approximately 0.5 mol of phosphate/IGF-II binding site after 10 min of incubation at 4 degrees C. A Km for ATP of 6 microM was calculated for this phosphorylation reaction. Addition of IGF-II caused an approximately 2-fold increase in tyrosine phosphorylation of the IGF-II receptor in this preparation. In contrast, phosphorylation of angiotensin II by the Triton X-100 washed membranes was not stimulated by IGF-II. Incubation of purified receptor immobilized on IGF-II agarose or of receptor-enriched low density microsomal membranes with (gamma-32P)ATP did ...
Fragrance mix II (FM II) is a relatively new screening marker for fragrance contact allergy. It was introduced in the patch test baseline series in Denmark in 2005 and contains six different fragrance chemicals commonly present in cosmetic products and which are known allergens.
Fatty acid biosynthesis is crucial for all living cells. In contrast to higher organisms, bacteria use a type II fatty acid synthase (FAS II) composed of a series of individual proteins, making...Full Text Available
... materials science and engineering, condensed-matter or materials physics, solid-state or materials ... include materials theory, condensed-matter and materials physics, solid-state and materials ...
The structural ordering of oxygen deficient and Co-doped YBCO (YBa_2Cu_3_-_yCo_yO_6_+_x) have been studied experimentally, and by computer simulations of the oxygen ordering in the basal plane of the structure. The calculations are based on the two-dimensional ASYNNNI model and its modifications. Good agreement is established between the ASYNNNI calculations and the experimentally observed structural properties of the double cell ortho-II structure and the oxygen disordering process from Co-doping into the basal plane. A model that relates the superconducting transition temperature T_c(x) of undoped YBCO and T_c(y) of Co-doped YBCO to the formation of specific domains of the two orthorhombic ordered oxygen phases, ortho-I and ortho-II, shows a close agreement with experimental T_c(x) and T_c(y) data of samples prepared under equilibrium conditions. The structural changes as a result of metal ion substitutions and oxidation/reduction processes ...
Some acylhydrazine derived ONO donor Schiff bases and their Co(II) and Ni(II) complexes have been prepared having the same metal ion (cation) but different anions. These synthesized metal(II) complexes have been characterized on the basis of their elemental analyses, magnetic moment, molar conductance, and IR and electronic spectral data. All of the Schiff base ligands function as tridentates and the deprotonated enolic form is preferred for coordination. In order to evaluate the effect of anions on the bactericidal activity, these synthesized complexes, in comparison to the uncomplexed Schiff bases have been screened against bacterial species., Escherichia coli, Staphylococcus aureus and Pseudomonas aeruginosa and the results are reported. PMID:18475936
We determined the chromosomal localization and structure of the gene encoding human type II inosine 5{prime}-monophosphate dehydrogenase (IMPDH, EC 1.1.1.205), an enzyme associated with cellular proliferation, malignant transformation, and differentiation. Using polymerase chain reaction (PCR) primers specific for type II IMPDH, we screened a panel of human-Chinese hamster cell somatic hybrids and a separate deletion panel of chromosome 3 hybrids and localized the gene to 3p21.1{yields}p24.2. Two overlapping yeast artificial chromosome clones containing the full gene for type II IMPDH were isolated and a physical map of 117 kb of human genomic DNA in this region of chromosome 3 was constructed. The gene for type II IMPDH was localized and oriented on this map and found to span no more than 12.5 kb.
In this study we compared various maturity dependent aromatic, steroid and triterpenoid hydrocarbon ratios in bitumens that are freely extractable from sedimentary rocks (Bitumen I) with those in second extracts that comprised hydrocarbons closely associated with the kerogen/mineral matrix (Bitumen II). Bitumen II was released through kerogen isolation and demineralisation using HCl and HF/H3BO3. The samples studied, although of similar age, come from different localities. They represent a range of facies and two kerogen types (II and III), and all were deposited under marine conditions. The results show that the more stable b isomers of methylnaphthalene (MN) and methylphenanthrene (MP) are relatively more abundant in Bitumen II. The difference between the methylnaphthalene ratio (MNR) of...
In this study, the biosorption of Cd(II), Ni(II) and Pb(II) on Aspergillus niger in a batch system was investigated, and optimal condition determined by means of central composite design (CCD) under response surface methodology (RSM). Biomass inactivated by heat and pretreated by alkali solution was used in the determination of optimal conditions. The effect of initial solution pH, biomass dose and initial ion concentration on the removal efficiency of metal ions by A. niger was optimized using a design of experiment (DOE) method. Experimental results indicated that the optimal conditions for biosorption were 5.22 g/L, 89.93 mg/L and 6.01 for biomass dose, initial ion concentration and solution pH, respectively. Enhancement of metal biosorption capacity of the dried biomass by pretreatment with sodium hydroxide was observed. Maximal removal efficiencies for Cd(II), Ni(III) and ...
The radiation reduction of bis(1-ethylimidazole)tartratoplatinum(II) (EITPt(II)) complexes in methanol-water solution have been examined. The yields of Pt(I) depend on the presence of O{sub 2} in solutions as well as the dose applied. The rate constants of e{sub s}{sup -} scavenging by EITPt(II) and cis(diammine-1,1-cyclobutanedicarboxylato) platinum(II) (CBDCAPt(II)) have been determined by pulse radiolysis to be equal to 5.4 x 10{sup 9} and 6.4 x 10{sup 9} M{sup -1} s{sup -1}, respectively. The efficiencies of e{sub t}{sup -} scavenging by EITPt(II) and the rate of e{sub t}{sup -} photobleaching have also been determined in LiCl : H{sub 2}O : CH{sub 3}OH and MgCl{sub 2} : H{sub 2}O : CH{sub 3}OH glasses, respectively. (author).
Materials World Network: Cooperative Activity in Materials Research between US Investigators and ... Program Title: Materials World Network: Cooperative Activity in Materials Research between US ...
Materials World Network: Cooperative Activity in Materials Research between US Investigators and ... Program Title: Materials World Network: Cooperative Activity in Materials Research between US ...
This definitive reference is organized in an easy-to-follow format based on materials properties. It features new and existing data verified through major professional societies in the materials fields, such as ASM International and the American Ceramic Society. The third edition has been significantly expanded, most notably by the addition of new tabular material for a wide range of nonferrous alloys and various materials. The contents include: Structure of materials; Composition of materials; Phase diagram sources; Thermodynamic and kinetic data; Thermal properties of materials; Mechanical properties of materials; Electrical properties of materials; Optical properties of materials; Chemical properties of materials.
The palladium(II) and platinum(II)complexes(where, (M(L){sub 2}X{sub 2}), M=Pd(II), Pt(II); L=isoxazole (isox), 3, 5-dimethylisoxazole(3, 5-diMeisox), 3-methyl, 5-phenylisoxazole(3-Me, 5-Ph-isox), and 4-amino-3, 5-di-methylisoxazole (4-ADI); X=Cl, Br) with isoxazole and its derivatives were investigated on antitumor activity by MM2 and EHMO calculation. Because for all the complexes the {sigma}MO energy level (E{sub {sigma}}{sub (M-X)} between d{sub x}{sup 2}{sub -y}{sup 2} orbital of central metal and p{sub x} orbital of halogen atom is less than {sigma}MO energy level E{sub {sigma}}{sub (M-N)} between d{sub x}{sup 2}{sub -y}{sup 2} orbital of central metal and p{sub x} orbital of N atom, without exception. And judging, from the lower E{sub {sigma}}{sub (M-X)} value in trans, the bonding strength was found to be weaker in trans isomer than in cis. For the Pd(II) and ...
Varying coordination modes of the Schiff base ligand H"2L [5-methyl-1-H-pyrazole-3-carboxylic acid (1-pyridin-2-yl-ethylidene)-hydrazide] towards different metal centers are reported with the syntheses and characterization of four mononuclear Mn(II), Co(II), Cd(II) and Zn(II) complexes, [Mn(H"2L)(H"2O)"2](ClO"4)"2(MeOH) (1), [Co(H"2L)(NCS)"2] (2), [Cd(H"2L)(H"2O)"2](ClO"4)"2 (3) and [Zn(H"2L)(H"2O)"2](ClO"4)"2 (4), and a binuclear Cu(II) complex, [Cu"2(L)"2](ClO"4)"2 (5). In the complexes 1-4 the neutral ligand serves as a 3N,2O donor where the pyridine ring N, two azomethine N and two carbohydrazine oxygen atoms are coordinatively active, leaving the pyrazole-N atoms inactive. In the case of complex 5, each ligand molecule behaves as a 4N,O donor utilizing the pyridine N, one azomethine N...
The biosorption characteristics of Pb(II) and Cd(II) ions from aqueous solution using the green alga (Ulva lactuca) biomass were investigated as a function of pH, biomass dosage, contact time, and temperature. Langmuir, Freundlich and Dubinin-Radushkevich (D-R) models were applied to describe the biosorption isotherm of the metal ions by U. lactuca biomass. Langmuir model fitted the equilibrium data better than the Freundlich isotherm. The monolayer biosorption capacity of U. lactuca biomass for Pb(II) and Cd(II) ions was found to be 34.7 mg/g and 29.2 mg/g, respectively. From the D-R isotherm model, the mean free energy was calculated as 10.4 kJ/mol for Pb(II) biosorption and 9.6 kJ/mol for Cd(II) biosorption, indicating that the biosorption of both metal ions was taken place by chemisorption. The calculated thermodynamic parameters ({delta}G{sup o}, ...
NSF-NIST Interaction in Chemistry, Materials Research, Molecular Biosciences, Bioengineering, and ... Laboratory (CSTL). Materials research is centralized in the Materials Science and Engineering ...
A method is described for immobilizing or solidifying waste material, which includes blending the waste material with powdered metal and subjecting the mixture of waste material and powdered metal to high pressure. (author).
... Schioler (703) 306-1836 lschiole@nsf.gov This material is available primarily for archival purposes ... of superconducting materials. Colossal magnetoresistance materials are those in which the electrical ...
... of this material is, however, outside the currently approved earth fill materials collection area ... fill material suitable for its intended use. The currently approved site contains material that is ...
The investigated hybrid nanocomposite consists of a porous silicon template with electrochemically embedded Ni or Co nanostructures and offers magnetic characteristics which can be tailored by the electrochemical process parameters during fabrication. A twofold magnetic behaviour can be observed, a first one due to the spinmagnetism at magnetic fields below the saturation magnetization of the deposited metals and a second non-saturating term at higher fields (>1 T up to 7 T) above the saturation magnetization. In case of Ni deposited within the pores this non-saturating term shows a paramagnetic characteristic and follows exactly the Curie-Weiss law, whereas for Co/porous silicon samples the temperature dependent magnetization shows some deviations from the Curie Weiss law. In this high field region a difference in the temperature dependence between Ni and Co is observed whereas the non-saturating term does not depend on the geometry of the embedded ...
This paper introduces a new method to produce nano-composite powder for the preparation of high performance ZnO varistors. ZnO particles were coated with Bi{sub 2}O{sub 3}, Sb{sub 2}O{sub 3}, Co{sub 2}O{sub 3}, Cr{sub 2}O{sub 3} and other additives via liquid nano-coating technique. Then the prepared powder was characterized by scanning electron microscopy (SEM), transmission electron microscopy (TEM), thermal gravity and differential scanning calorimetry (TG-DSC) and particle size distribution. The results showed that the ZnO composite powder is homogeneously coated and ultrafine. The densification, phase composition and microstructure of ZnO varistors was studied by linear shrinkage, X-ray diffraction (XRD) and SEM, respectively. The preliminary electrical parameters of ZnO varistors showed that the breakdown voltage V {sub b} (1 mA/cm{sup 2}) and nonlinear coefficient {alpha} is 5400 V/cm and 50, respectively, much higher than that of conventional ball milling ...
Functionalizing nanoparticle surfaces is essential for achieving homogeneous dispersions of monodisperse particles in polymer nanocomposites for successful utilization in engineering applications. Functionalization reduces the surface energy of the nanoparticles, thereby limiting the tendency to agglomerate. Moreover, reactive groups on the surface can also participate in the polymerization, creating covalent bonds between the inorganic and organic phases. In this paper, a fluidized bed inductively coupled plasma (FB-ICP) reactor is used to break apart the agglomerates and functionalize commercial TiO2 nanoparticle powders in a batch of several grams. The fluidized bed could be implemented into a continuous flow reactor, potentially making this a viable method to treat larger quantities of commercial powders. The particles are treated with acrylic acid (AA) and tetraethylorthosilicate (TEOS) plasma and the functionalized particles were collected separately from ...
In the present study, new light weight nano-composites (AZ31B-3.3Al2O3-Cu) based on magnesium alloy AZ31B are developed using disintegrated melt deposition technique. Microstructural characterization studies revealed grain refinement and significant increase in amount of second phases as a result of increasing presence of copper. All the samples exhibited minimal porosity and good matrix-second phase interfacial integrity. The results also showed that addition of both nano-Al2O3 and Cu led to a simultaneous improvement in 0.2% yield compressive strength (0.2%YCS), ultimate compressive strength (UCS) and work of fracture (WoF) of the AZ31B magnesium alloy while failure strain was marginally affected. The results of this study clearly illustrate the capability of AZ31B-Al2O3-Cu formulations ...
The nanocomposite WC-Co powders were prepared through planetary ball milling method. Effects of grain growth inhibitor addition and the vacuum sintering parameters on the microstructure and properties of ultrafine WC-10Co cemented carbides were investigated using X-ray diffractometer, scanning electron microscope and mechanical property tester. The results show that VC and NbC additions can refine the WC grains, decrease the volume fraction of Co3W3C phase in ultrafine WC-10Co cemented carbides, and increase the hardness and fracture toughness of the base alloys. After sintering for 60 min at 1400 degreeC, the average grain size and hardness of ultrafine-grained WC-10Co-1VC cemented carbide are 470 nm and HRA 91.5, respectively. The fracture toughness of cemented carbide WC-10Co-1NbC alloy...
Dye-sensitized solar cells (DSSCs) based on anatase TiO2 hollow spheres (TiO2HS)/multi-walled carbon nanotubes (CNT) nanocomposite films are prepared by a directly mechanical mixing and doctor blade method. The prepared samples are characterized by scanning electron microscopy, transmission electron microscopy, X-ray diffraction, UV-vis absorption spectroscopy and N2 adsorption-desorption isotherms. The photoelectric conversion performances of the DSSCs based on TiO2HS/CNT composite film electrodes are also compared with commercial-grade Degussa P25 TiO2 nanoparticles (P25)/CNT composite solar cells at the same film thickness. The results indicate that the photoelectric conversion efficiencies () of the TiO2HS/CNT composite DSSCs are dependent on CNT loading in the electrodes. A small amou...
We report a templated-synthetic approach based on apoferritin to prepare radionuclide nanoparticle (NP) conjugates. Non-radioactive yttrium (89Y) was used as model target and surrogate for radioyttrium (90Y) to prepare the nanoparticle conjugate. The center cavity and multiple channel structure of apoferritin offer a fast and facile method to precipitate yttrium phosphate by diffusing yttrium and phosphate ions into the cavity of apofrritin, resulting a core-shell nanocomposite. The yttrium phosphate/apoferritin nanoparticle was functionalized with biotin for further application. The synthesized nanoparticle was characterized by transmission electron microscopy (TEM) and x-ray photoelectron spectroscopy (XPS). We found that the resulting nanoparticles were uniform in size, with a diameter of around 8 nm. We tested the pre-targeting capability of the biotin-modified yttrium phosphate/apoferritin nanoparticle (yttrium phosphate/apoferritin nanoparticle) conjugate ...
A tri-functional polyhedral oligomeric silsesquioxane (POSS) based silane precursor R_xR_yR_z(SiO_3_/_2)_n (x + y + z = n = 6, 8, 10, ...) bearing 3-(N-(3-triethoxysilylpropyl)ureido)propyl, isooctyl and perfluoropropyl groups was synthesized and investigated as corrosion protective coating for AA 2024 alloy. Infrared reflection-absorption (IR RA) combined with X-ray photoelectron spectroscopy and atomic force microscopy provided information about partial self-assembling of coatings having a fluorine enriched upper layer with a low surface energy (#gamma#"t"o"t = 12.37 mN/m). The structural changes that accompanied corrosion produced under chronocoulometrical conditions were assessed from ex-situ IR RA spectra. A new band at 1690-1700 cm"-"1 appeared above the corrosion potential, and was assigned to the formation of amidonium ions and consequent relaxation of urea-urea associations.
The interaction of cis-diamminediaquoplatinum(II) nitrate with adenosylcobalamin and a series of alkylcobalamins was studied by carbon-13 nuclear magnetic resonance spectroscopy and by electronic spectroscopy. With these cobalamins cis-(Pt(NH/sub 3/)/sub 2/(OH/sub 2/)/sub 2/)/sup 2 +/ forms adducts in which N(3) of the 5,6-methylbenzimidazole moiety is co-ordinated to platinum(II) rather than to cobalt(III) of the corrin. The chemical shifts of the 5'-methylene carbon of adenosylcobalamin-platinum adduct and of the Co-methyl carbon of the methylcobalamin-platinum adduct are characteristic of these cobalamins in the base-off form. Furthermore, these cobalamin-platinum complexes have visible spectra identical to those of the cobalamins in acidic solution. The /sup 13/C NMR spectrum of the adenosylcobalamin-platinum complex suggests the presence of a second adduct in which platinum(II) complexes are co-ordinated to ...
The relationship between serum PG I, PG II levels and extent of atrophic gastritis was examined. The subjects were 64 patients (male: 32, female: 32, 51.9 years old on average) with established diagnosis of either atrophic gastritis or normal. In the X-ray gastric examination, Fuji Computed Radiography (FCR) was used to obtain clear-cut images of the gastric area. Concerning the serum PG I level, patients in the group with atrophic gastritis showed lower levels than those of the people in the group with no atrophic change, but the variation was wide, and no definite tendency was seen in the relationship between the atrophic change and the serum PG I levels. Concerning the serum PG II level, as the atrophic change progresses, the serum PG II level tended to increase gradually. A significant reduction in the PG I/II ratio was seen in the group with atrophic changes (p<0.01) in comparison with the group ...
The relationship between serum PG I, PG II levels and extent of atrophic gastritis was examined. The subjects were 64 patients (male: 32, female: 32, 51.9 years old on average) with established diagnosis of either atrophic gastritis or normal. In the X-ray gastric examination, Fuji Computed Radiography (FCR) was used to obtain clear-cut images of the gastric area. Concerning the serum PG I level, patients in the group with atrophic gastritis showed lower levels than those of the people in the group with no atrophic change, but the variation was wide, and no definite tendency was seen in the relationship between the atrophic change and the serum PG I levels. Concerning the serum PG II level, as the atrophic change progresses, the serum PG II level tended to increase gradually. A significant reduction in the PG I/II ratio was seen in the group with atrophic changes (p<0.01) in comparison with the group ...
The biosorption characteristics of Cd(II) ions using the red alga (Ceramium virgatum) were investigated. Experimental parameters affecting the biosorption process such as pH, contact time, biomass dosage and temperature were studied. Langmuir, Freundlich and Dubinin-Radushkevich (D-R) models were applied to describe the biosorption isotherms. The biosorption capacity of C. virgatum biomass for Cd(II) ions was found to be 39.7 mg/g. From the D-R isotherm model, the mean free energy was calculated as 12.7 kJ/mol, indicating that the biosorption of Cd(II) the metal ions was taken place by chemisorption. The calculated thermodynamic parameters ({delta}G{sup o}, {delta}H{sup o} and {delta}S{sup o}) showed that the biosorption of Cd(II) ions onto C. virgatum was feasible, spontaneous and exothermic at 293-323 K. Evaluation of experimental data in terms of biosorption kinetics showed that the biosorption of ...
Apparent molar volumes V{sub phi} and apparent molar heat capacities C{sub p,phi} were determined for aqueous solutions of nickel(II) nitrate, copper(II) nitrate, and zinc(II) nitrate at molalities m=(0.01 to 0.5) mol {center_dot} kg{sup -1}, and at the pressure p=0.35 MPa. Solution densities obtained using a vibrating-tube densimeter at T=(278.15 to 368.15) K were used to calculate V{sub phi} values. Heat capacity measurements obtained with a twin fixed-cell, differential-output, power-compensating, temperature-scanning calorimeter at T=(278.15 to 393.15) K were used to calculate values of C{sub p,phi}. Our results were then fitted to functions of m and T and compared to literature values.
The aim of this case study is to analyse the socio-economic effects of forest fuel supply and use chains. Two of the four cases are rural district heating plants. In Perho, the co-operative organisation of forest owners maintains the fuel supply and operates the plant. In Ruukki, the local forestry association supplies forest chips to the plant. These medium-scale plants use small-sized trees from young thinning stands as their main fuel. The trees are felled manually. The other two cases are large power plants. Alholmens Kraft's new power plant in Pietarsaari aim to use 250 000 solid-m3 of forest chips annually. The logging residues are hauled to the plant as bales using traditional timber harvesting equipment or as bulk material. At young thinning stands the trees are harvested using an accumulating feller buncher. The Toppila I and II power plants in the city of Oulu used about 36 000 solid-m3 of forest chips. Over 300 000 solid-m3 ...
From 1946 - 1990, i.e. from shortly after the end of World War II and the rise of the cold war until the German reunification, there had been extensive uranium mining both in Saxony and Thuringia, which formed the southern parts of the former German Democratic Republic. Mining activities started in Saxony in the Ore Mountains (German: Erzgebirge). Mining was conducted by a Soviet, since 1954 by a Soviet- German Incorporated Company named Wismut. It is estimated that about 400,000 persons may have worked in this time period with the company, most of them underground or in uranium ore processing facilities. In the early years, exposure to radiation and dust was particularly high for underground workers. After introduction of several ventilation measures and wet drilling from 1955 onwards, the levels of exposures to the various agents steadily decreased. After German reunification, it was decided by the German Federal Ministry for the Environment to save health data ...
This Streamlined Approach for Environmental Restoration (SAFER) plan addresses closure for Corrective Action Unit (CAU) 118, Area 27 Super Kukla Facility, identified in the ''Federal Facility Agreement and Consent Order''. Corrective Action Unit 118 consists of one Corrective Action Site (CAS), 27-41-01, located in Area 27 of the Nevada Test Site. Corrective Action Site 27-41-01 consists of the following four structures: (1) Building 5400A, Reactor High Bay; (2) Building 5400, Reactor Building and access tunnel; (3) Building 5410, Mechanical Building; and (4) Wooden Shed, a.k.a. ''Brock House''. This plan provides the methodology for field activities needed to gather the necessary information for closing the CAS. There is sufficient information and process knowledge from historical documentation and site confirmation data collected in 2005 and 2006 to recommend closure of CAU 118 using the SAFER process. The Data ...
In 2004, the Southeastern France regional council asked the regional health observatory to conduct an environmental health inventory to i) identify environmental health problems in this area; ii) examine the relations between environmental exposure to pollutants and human health; and iii) help public officials to identify priorities in this area. We collected and validated data from national, regional and local institutions, constructed environmental (levels of emissions and pollutants), health (mortality, incidence, prevalence) and behavioral indicators (e.g., complaints about odors), and compared these over time and between places when possible. For each topic, we summarized current knowledge about the links between environment and health. In southeastern France, as in other French areas, indoor air pollution, home and leisure injuries and other home-related risks are public health issues. Other topics are more significant or particular to southeastern France: ...
The full text follows. A thermal neutron imaging facility (TNIF) capable of real time neutron radiography and computed tomography was developed for the University of Texas TRIGA Mark II (UT-TRIGA) reactor from 1994-1998. The facility was developed with a through reactor beam port capable of producing a 5.2 x 10{sup 6} n/cm{sup 2}/s thermal neutron flux with a gamma dose rate of less than 1 mR/s after collimation. The original TNIF included the UT-TRIGA reactor, neutron collimation array, sample positioning system, neutron image intensifier tube, video camera, computerized image acquisition system, and a radiation shield. A 0.7 mm slit in cadmium was easily detectable using neutron radiography, and 1.4 mm diameter holes bored in an aluminum block were easily resolved using computed neutron tomography. Precise lower limits of the system resolution have hot been determined. The TNIF is currently being revamped to begin work with the non-destructive evaluation (NDE) of ...
PURPOSE: To determine the recommended dose of radiotherapy when combined with full-dose gemcitabine and erlotinib for unresected pancreas cancer. METHODS AND MATERIALS: Patients with unresected pancreatic cancer (Zubrod performance status 0-2) were eligible for the present study. Gemcitabine was given weekly for 7 weeks (1,000 mg/m(2)) with erlotinib daily for 8 weeks (100 mg). A final toxicity assessment was performed in Week 9. Radiotherapy (starting at 30 Gy in 2-Gy fractions, 5 d/wk) was given to the gross tumor plus a 1-cm margin starting with the first dose of gemcitabine. A standard 3 plus 3 dose escalation (an additional 4 Gy within 2 days for each dose level) was used, except for the starting dose level, which was scheduled to contain 6 patients. In general, Grade 3 or greater gastrointestinal toxicity was considered a dose-limiting toxicity, except for Grade 3 anorexia or Grade 3 fatigue alone. RESULTS: A total of 20 patients were treated (10 men and 10 ...
Manganese is a common contaminant of mine water and other waste waters. Due to its high solubility over a wide pH range, it is notoriously difficult to remove from contaminated waters. Previous systems that effectively remove Mn from mine waters have involved oxidising the soluble Mn(II) species at an elevated pH using substrates such as limestone and dolomites. However it is currently unclear what effect the substrate type has upon abiotic Mn removal compared to biotic removal by in situ micro-organisms (biofilms). In order to investigate the relationship between substrate type, Mn precipitation and the biofilm community, net-alkaline Mn-contaminated mine water was treated in reactors containing one of the pure materials: dolomite, limestone, magnesite and quartzite. Mine water chemistry and Mn removal rates were monitored over a 3-month period in continuous-flow reactors. For all substrates except quartzite, Mn was removed from the mine water ...
The meeting featured seven sessions with 18 papers abstracted/indexed therein as follows: keynote address: tailings dams safety - implications for the dam safety community; 1 - design and performance: performance monitoring of dams: are we doing what we should be doing?; tailings dams from the perspective of conventional dam engineering; and design overview of Syncrude's Mildred Lake east toe berm; 2 - design and modelling: use of a 2D model for a dam break study on the ALCAN hydroelectric complex in Quebec; and spillway design implications resulting from changes in rainfall extremes; 3 - risk and dam safety I: closing the gaps in the dam safety guidelines; the reality of life safety consequence classification; and surveillance practices for the next millenium; 4 - risk and dam safety II: quantitative risk-assessment using the capacity-demand analysis; and new guidelines for dam safety classification; 5 - millenium issues: expectations of immortality, dam ...
This is the 1st revision of the INIS/ETDE Joint Thesaurus. It contains 20 953 valid descriptors and 8 600 forbidden terms. It was last updated in December 2003. The Joint Thesaurus contains the controlled terminology for indexing all information within the subject scope of both INIS (International Nuclear Information System) and ETDE (Energy Technology Data Exchange) information systems. The terminology is intended for use in subject description for input or retrieval of information in those systems. The thesaurus is a terminological control device used in translating from the natural language of documents, indexers or users into a more constrained system language It is also a controlled and dynamic vocabulary of semantically and generically related terms which covers a specific domain of knowledge. The domain of knowledge covered by this Thesaurus includes physics (in particular, plasma physics, atomic and molecular physics, and especially nuclear and high-energy physics), chemistry, ...
Intermetallic compounds based on the Al-Co system were synthesized by solid state method - mechanical alloying and their properties were investigated using XRD, SEM, and DSC. The powder was used to make new targets of irradiation for gamma sources in order to enhance the specific activity and to reduce the consumption of material. The intermetallic compound AlCo was formed in the first 4 hours of milling. After 8 hours of milling the medium size of crystallites were of 5.58 nm. This value decreases with the increase of milling time up to 3 nm, corresponding to the 28 hours of grinding. There was calculated and plotted the Gibbs function, #DELTA#_f"0, for the reaction of formation AlCo and Al_3Co from the Al-Co system. It had negative values over the entire range of temperatures for both investigated compounds. After 28 hours milling a phase composition was obtained as follows: 0.2% Al; 21%Co ; 55.5%AlCo; 23.3% Al_1_3Co_4. AlCo 98% has been obtained after a ...
Investigation and flow testing of the enlarged Phase I heat-extraction system at Fenton Hill continued throughout FY80. Temperature drawdown observed at that time indicated an effective fracture of approximately 40,000 to 60,000 m/sup 2/. In May 1980, hot dry rock (HDR) technology was used to produce electricity in an interface demonstration experiment at Fenton Hill. A 60-kVA binary-cycle electrical generator was installed in the Phase I surface system and heat from about 3 kg/s of geothermal fluid at 132/sup 0/C was used to boil Freon R-114, whose vapor drove a turboalternator. A Phase II system was designed and is now being constructed at Fenton Hill that should approach commercial requirements. Borehole EE-2, the injection well, was completed on May 12, 1980. It was drilled to a vertical depth of about 4500 m, where the rock temperature is approximately 320/sup 0/C. The production well, EE-3 had been drilled to a depth of 3044 m and drilling was continuing. ...
Runit Island on Enewetak Atoll was very heavily impacted by the U.S. nuclear testing campaign in the northern Marshall Islands (1946-58). The primary source of contamination on Runit Island was the 1958 Quince safety test where a large quantity of device plutonium (Pu) was scattered over the area near the GZ. A second low-yield device was detonated on the same site 10 days later, further disturbing the soil and leaving behind a very heterogeneous pattern of contamination including milligram-size particles of plutonium. A limited cleanup of the Fig-Quince zone was carried out in 1979. During this period, the effectiveness of the cleanup operations was primarily evaluated on the basis of bulk soil concentration data with little consideration given to the heterogeneity and long-term material-, biological-, and environmental-specific impacts of residual high activity (hot) particle contamination. The aim of the present study was twofold; (i) to characterize the levels ...
We apply our previously developed first-principles nonlocal pseudopotentials (obtained for all atoms of rows 1--5 in the Periodic Table) to study self-consistently the electronic structure of Si and Ge and the transition metals Mo and W. For Si and Ge we find that the first-principles pseudopotentials yield valence-band states in good agreement with the empirically adjusted pseudopotential and photoemission data, whereas the low conduction-band states appear to be consistently lower in energy due apparently to incomplete cancellation of the self-interaction effects. The calculated x-ray scattering factors (obtained by core orthogonalization of the pseudo-wave-functions) are in excellent agreement with experiment. The self-consistent valence charge density shows a distinct elongation of the covalent bond along the internuclear axis, in good agreement with the experimentally synthesized density. The systematic deviations of the empirical pseudopotential results from the present are ...
Full text: Semiconductor detectors coated with boron or lithium compounds have been studied for neutron detection for decades but, until recently, have been limited to thermal neutron detection efficiencies of less than 5%. We reported previously on development and simulation studies of perforated detectors whose perforations are filled with neutron-reactive material in order to produce higher detection efficiencies. Incorporation of bare and cadmium-backed detectors into battery-powered devices with low-power electronics enables us to produce compact personal neutron dosimeters that provide LED readout of counts, which can be related approximately to neutron dose. We report here on experimental studies with such compact devices; devices capable of direct readout in dose units are anticipated. The thermal and epithermal neutron flux densities from the tangential beam tube of the TRIGA Mark II reactor at Kansas State University were measured. ...
The field of neutron imaging has a broad scope of applications and has played a pivotal role in visualizing and quantifying hydrogenous masses in metallic matrices. The field continues to expand into new applications with the installation of new neutron imaging facilities. In this scope, a neutron imaging facility for computed tomography and real-time neutron radiography is currently being developed around 2.0 MW TRIGA MARK-II Reactor at Maamora Nuclear Research Centre in Morocco (CENM). The neutron imaging facility consists of a neutron collimator, a real-time neutron imaging system and imaging process systems. In order to reduce the gamma-ray content in the neutron beam, the reactor tangential channel was selected. For power of 250 kW, the corresponding thermal neutron flux measured at the inlet of the tangential channel is around 3.10{sup 11} n*cm{sup 2}/s. This facility will be based on a conical neutron collimator with two circular diaphragms with diameters of ...
The field of neutron imaging has a broad scope of applications and has played a pivotal role in visualizing and quantifying hydrogenous masses in metallic matrices. The field continues to expand into new applications with the installation of new neutron imaging facilities. In this scope, a neutron imaging facility for computed tomography and real-time neutron radiography is currently being developed around 2.0 MW TRIGA MARK-II Reactor at Maamora Nuclear Research Centre in Morocco (CENM). The neutron imaging facility consists of a neutron collimator, a real-time neutron imaging system and imaging process systems. In order to reduce the gamma-ray content in the neutron beam, the reactor tangential channel was selected. For power of 250 kW, the corresponding thermal neutron flux measured at the inlet of the tangential channel is around 3.1011 n*cm2/s. This facility will be based on a conical neutron collimator with two circular diaphragms with diameters of 4 cm and 2 ...
The samples comprise the foliage of four pteridosperm-medullosalean plant fossil species of differing preservation states and one of a cordaitean species from two Canadian Maritime sub-basins of Carboniferous age (300 Ma; Sydney and Stellarton coalfields, Nova Scotia, respectively). Included in the sample set were some coal samples from Sydney Coalfield, along with published data for coal macerals for comparison. By applying Schulze's maceration process to the fossil foliage to obtain the cuticles, five sample forms evolved, viz. compressions, cuticles and fossilized cuticles, and acidic and alkaline solutions from Schulze's process, to which was added the Sydney coal samples as the sixth form. Area integration of the absorbance spectra from solid and liquid state Fourier transform infrared (FTIR) spectroscopy, produced functional chemical parameters which were organized into a data matrix of eight variables and 62 samples (8 x 62 matrix). Principal components were ...
Samarium cobaltite ceramic perovskites, with and without platinum particles dispersion, are possible candidates as electrode for electrochemical conversion of hydrocarbon and for intermediate temperature solid oxide fuel cells (ITSOFC). In this work, samarium cobaltites were synthesized by the combustion method using cobalt, and samarium nitrates as cation precursors and urea as fuel. For containing-platinum compositions Pt (II) acetyl acetonate was also employed as precursor. The effect of Sr on the phase formation and its electrical behavior is also studied. Specific surface area (BET), SEM-EDX, TEM and XRD analysis are used to characterize the powders obtained. Powders were pressed into pellets and sintered in air in the temperature range of 1200 -1400 C. Electrical impedance spectroscopy studies (EIS) are performed on sintered samples. The as-prepared powders showed an amorphous structure and by TEM a very small particle size ({proportional_to}10 nm) was ...
This report presents highlights of activities in the Acceleartor Technology (AT) Division from April through December 1978. The report is divided into 10 sections to cover work done by the four groups that make up AT Division (AT-1, AT-2, AT-3, and AT-4). Section I is a brief summary of the whole report. Sections II through VI describe work done by At-1, the Linac Technology Group. Subjects covered are the Pion Generation for Medical Irradiation Program, the Electronuclear Fuel-Producing Accelerator Program, the Gyrocon rf Amplifier Program, the Electron Linear Accelerator Program, and the Free Electron Laser Program. Section VII covers the Linear Accelerator Beam Dynamics development, and Sec. VIII deals with work with the H/sup -/ Ion Source. Most of the work in Secs. VII and VIII was done by AT-2, the Special Projects Group, although work on factors influencing emittance growth was done by MP-9, and results on emittance growth in the new European Council for ...
Los Alamos National Laboratory (LANL) was established during World War II with a single mission -- to design and build an atomic bomb. In the 65 years since, nuclear weapons physics, design and engineering have been the Laboratory's primary and sustaining mission. Experimental and process operations -- and associated cleanout and upgrade activities -- have generated a significant inventory of transuranic (TRU) waste that is stored at LANL's Technical Area 54, Material Disposal Area G (MDA G). When the Waste Isolation Pilot Plant (WIPP) opened its doors in 1999, LANL's TRU inventory totaled about 10,200 m{sup 3}, with a plutonium 239-equivalent curie (PE Ci) content of approximately 250,000 curies. By December 2008, a total of about 2,300 m3 (61,000 PE Ci) had been shipped to WIPP from LANL. This has resulted in a net reduction of about 1,000 m{sup 3} of TRU inventory over that time frame. This paper presents progress ...
Boron Neutron Capture Therapy (BNCT) is a promising binary treatment modality for high-grade primary brain tumors (glioblastoma multiforme, GM) and other cancers. BNCT employs a boron-10 containing compound that preferentially accumulates in the cancer cells in the brain. Upon neutron capture by {sup 10}B energetic alpha particles and triton released at the absorption site kill the cancer cell. In order to gain penetration depth in the brain Fairchild proposed, for this purpose, the use of energetic epithermal neutrons at about 10 keV. Phase I/II clinical trials of BNCT for GM are underway at the Brookhaven Medical Research Reactor (BMRR) and at the MIT Reactor, using these nuclear reactors as the source for epithermal neutrons. In light of the limitations of new reactor installations, e.g. cost, safety and licensing, and limited capability for modulating the reactor based neutron beam energy spectra alternative neutron sources are being contemplated for wider ...
This is the final report of a three year DOE funded project titled ''A real-time coal content/ore grade (C{sub 2}OG) sensor''. The sensor, which is based on hyperspectral imaging technology, was designed to give a machine vision assay of ore or coal. Sensors were designed and built at Resonon, Inc., and then deployed at the Stillwater Mining Company core room in southcentral Montana for analyzing platinum/palladium ore and at the Montana Tech Spectroscopy Lab for analyzing coal and other materials. The Stillwater sensor imaged 91' of core and analyzed this data for surface sulfides which are considered to be pathfinder minerals for platinum/palladium at this mine. Our results indicate that the sensor could deliver a relative ore grade provided tool markings and iron oxidation were kept to a minimum. Coal, talc, and titanium sponge samples were also imaged and analyzed for content and grade with promising results. This ...
This paper presents the characteristics of selected parameters of organic matter of the Tertiary coal samples and organic matter of Carboniferous rock samples from the Spitsbergen. The coal samples were taken from Central Coal Basin (the Longyearbyen region) and from the Forlandsundet Basin (Oscar II Land, the Kaffioyra region). Samples of dispersed organic matter were collected from Suffolk Pynten and Sergeijevfjellet area in Sorkapp Land. The optical properties of coal samples are different from properties of dispersed organic matter. Macerals of vitrinite group dominate in all of the samples. The average content of vitrinite group macerals is much lower in dipersed organic matter samples than it is in coals. The average content of liptinite group macerals is a little lower, and inertinite group macerals is much higher. The average content of mineral matter is higher in organic matter samples than in coal samples. The average value of vitrinite reflectance and ...
Mass accretion onto (proto-)stars at high accretion rates M-dot_*> 10"-"4 M_s_u_n yr"-"1 is expected in massive star formation. We study the evolution of massive protostars at such high rates by numerically solving the stellar structure equations. In this paper, we examine the evolution via disk accretion. We consider a limiting case of 'cold' disk accretion, whereby most of the stellar photosphere can radiate freely with negligible backwarming from the accretion flow, and the accreting material settles onto the star with the same specific entropy as the photosphere. We compare our results to the calculated evolution via spherically symmetric accretion, the opposite limit, whereby the material accreting onto the star contains the entropy produced in the accretion shock front. We examine how different accretion geometries affect the evolution of massive protostars. For cold disk accretion at 10"-"3 M_s_u_n yr"-"1, the radius of a protostar is ...
The aim of this paper was to describe ability to intercalation of laboratory prepared carbon composites and their constituents. In work the following materials were tested; pinch-based fibres of P-120 and K-1100 manufacturer's designations, carbon matrix and resulting composites. To prepare a matrix of composites, phenol-formaldehyde resin (Z) and pinch-based precursor (PAK) were used. After initial carbonization, the carbon matrix was heated to 2150 "oC i to improve ability to the future intercalation. Three kinds of composites (P/Z, K/Z and K/PAK), with two directional reinforcement (2D), were prepared. All carbon samples were intercalated with copper chloride(II). To study the structure of all materials, before and after intercalation, X-ray diffraction method was used. It enabled to measure microstructure parameters (L_c and L_a), interplanar distance (d_0_0_2) thickness of an intercalation layer (d_i). Before ...
The chemical operational concept originally established for the water-steam circuit of Angra II nuclear power plant has undergone several modifications throughout the development of the project. This work discusses the two main modifications giving special attention to the costs involved and analyses the main points and the consequences of such modifications 1 ref., 4 figs., 2 tabs.
System-level-operational testing of the ETX-II test-bed electric vehicle is described and the results discussed. Because the traction battery is a major factor in the performance of an electric vehicle, previously reported work on the sodium-sulfur battery designed for use with the ETX-II is reviewed in detail. Chassis dynamometer performance of the test-bed vehicle met or exceeded design goals and compared reasonably well with SIMPLEV computer modeling results. Areas are identified wherein further work is needed to establish a firmer basis for comparison of the simulation and the observed results.
A lot of effort has been made to spread the application of RTOS in embedded system development in China. RTOS, #mu#C/OS and #mu#C/OS-II, with its opened source code, is well known in embedded systems. Learning RTOS, Using RTOS, becomes more and more popular. The Book of 'Micro C/OS-II The Real-Time Kennel Second Edition' was published in 2002. Here some new progress of the RTOS, especially the safety certifications, the reliability of software is introduced. (authors)
The KENTORT II process includes integral fluidized bed zones for pyrolysis, gasification, and combustion of the oil shale. The purpose of this program is to design and test the KENTORT II process at the 50-lb/hr scale. Along with the major activity of assembling the components of the 50-lb/hr retort, work was also completed in other areas this quarter. Basic studies of the cracking and coking kinetics of model compounds in a fixed bed reactor were continued. Additionally, as part of the effort to investigate niche market applications for KENTORT II-derived products, a study of the synthesis of carbon fibers from the heavy fraction of KENTORT II shale oil was initiated.
Active Activator (Ac) elements undergo mutations to become nonautonomous Dissociation (Ds) elements at a low frequency. To understand...Full Text Available
... in Taylor and Williamson.* Most satellite sensors cannot be ... The coordinates of the rocket Ii ... I - Incoming Global Radiant Flux between 0.285 and ...
Abstract Copper(II) bis(thiosemicarbazone) are very useful for blood flow and hypoxic imaging. The aim of this study was to identify structure-activity relationships (SARs) within a series of analogues with different substitution patterns in the ligands, in order to design improved hypoxia imaging agents and elucidate hypoxia selectivity mechanisms. Genetic algorithms (GAs) were used to develop specific copper metal-ligand force field parameters for the MM3 force-field calculations. These new parameters produced results in good agreement with experiment and previously reported copper metal-ligand parameters. A successful quantitative SAR (QSAR) for predicting the several classes of Cu(II)-chelating ligands was built using a training set of 21 Cu(II) complexes. The QSAR exhibited a correlat...
missionaries and cannibals puzzle. He noted that in order to be able to use a boat to cross a river one would need ... a quali cation that the vertical exhaust stack ...
... And those who study cognition select problems (eg, tower of Hanoi, missionaries and cannibals, logic theorems) with minimal perceptual and motor ...
Form as the end result of massive star evolution; Type II supernova: collapse of iron core in highly evolved massive star; outer regions blasted away in ...
The biosorption of lead, copper and zinc ions on Rhizopus arrhizus has been studied for three single-component and two binary systems. The equilibrium data have been analysed using the Freundlich adsorption model. The characteristic parameters for the Freundlich adsorption model have been determined and the competition coefficients for the competitive biosorption of Pb(II)-Cu(II) at pH 4.0 and 5.0, and Pb(II)-Zn(II) at pH 5.0 have been calcualted. For the individual single-component isotherms, lead has the highest biosorption capacity followed by copper, then zinc. The capacity of lead in the two binary systems is always significantly greater than those of the other metal ions, in agreement with the single-component data. Only a partial selectivity for copper ions has been obtained at pH 4.0. (orig.)
Hexavalent chromium in corrosion preventive coating 64 ...To prevent corrosion of rims, weights can be provided with a coating. ...integrated clips brought up technical problems due to corrosion
... Science, Computer Vision, Digital Government, Digital Libraries, Digital Society and Technologies ... for Robust Intelligence, Digital Government, and Digital Libraries and Archives. In subsequent years ...
... Ready-to-Eat (MRE) VIII operational ration was evaluated at a field training exercise (Market Square II) with troops of the 82nd Airborne Division. ...
Given a double complex $X$ there are spectral sequences with the $E_2$ terms being either H$_I$ (H$_{II}(X))$ or H$_{II}($H$_I (X))$. But if $H_I(X)=H_{II}(X)=0$ both spectral sequences have all their terms 0. This can happen even though there is nonzero (co)homology of interest associated with $X$. This is frequently the case when dealing with Tate (co)homology. So in this situation the spectral sequences may not give any information about the (co)homology of interest. In this article we give a different way of constructing homology groups of $X$ when H$_I(X)=$H$_{II}(X)=0$. With this result we give a new and elementary proof of balance of Tate homology and cohomology.
This objective of this work was to summarize the main results obtained in previous papers related to the adsorbent-adsorbate interactions involved in the adsorption of naphthalenesulphonic acids and heavy metals (Cd(II) or Hg(II)) by modified activated carbons. The adsorption of organic compounds (1-naphthalenesulphonic acid, 1,5-naphthalenedisulphonic acid and 1,3,6-naphthalenetrisulphonic acid) and inorganic species (Cd(II) and Hg(II)) was studied on a series of ozonized activated carbon in aqueous phase. Commercial activated carbon (Filtrasorb 400) was treated with different ozone doses to study the effect of ozone treatment on its surface properties and investigate the behavior of the treated carbon samples in the above adsorption processes. After ozonation, carbonyl- and carboxyl-type...
A survey is given on the results in hand on the natural radioactivity of building materials. It is shown that only a small percentage of building materials has an increased content of radioactive materials. The results are compared with approximate values given in a Russian publication. (orig./AK).
... Highly-Functional Materials" was launched in JFY1996 under the New Materials field. This project was ... Bio-mimetic materials" (1) Advanced stimuli responsive materials (2) Harmonized molecular materials ...
... materials science and education beyond what is expected from any one Center. "Advanced materials are ... for DMR's Division of Materials Research. "Fundamental research on materials is essential to the ...
... 1995 Trilateral Materials Workshop PDF (202K) Report of the Workshop on Materials for Future ... in Materials Research Technology and Education PDF (163K) US-Asian Pacific Materials Research ...
This thesis deals with the evaluation of Solar Grade Silicon (SoG-Si) purified by different techniques, and also the fabrication and characterization of high efficiency and advanced bifacial solar cells. In the beginning of Chapter 1, various SoG-Si production methods relevant for this work are qualitatively described. The three feedstock materials used in this work are from the Fluidized Bed Reactor (FBR) process, metallurgical feedstock-I and feedstock-II process. In metallurgical feedstock-I, the lifetime of the minority charge carriers in multicrystalline silicon (mc-Si) samples at the grain boundaries are found to be higher than the grains themselves possibly due to lower resistivities in the grain boundaries. The efficiency of the best solar cell obtained using the mc-Si metallurgical feedstock-I is 16.1%. It has been identified that the fast light induced degradation, whose magnitude is lower than that of a reference cell suggests the ...
The results of the thermo-hydro-mechanical (THM) study of the FEBEX bentonite performed during FEBEX II are presented. The laboratory test program continued in part with the works carried out during FEBEX I, particularly in activities related to tests aimed to the calibration of the models, the acquisition of parameters by back-analysis and the improvement of the knowledge on the behaviour of expansive clays. But the program has also included tests on new areas: investigations about the influence of the microstructure changes in bentonite, of temperature and of the solute concentration on the behaviour of clay. Besides, several tests were proposed in order to understand the unexpected behaviour observed in the mock-up test, towards the end of year 2. Temperature effects on water retention curves in confined and unconfined conditions were determined, and swelling pressure, hydraulic conductivity and swelling and consolidation strains as a function of temperature ...
Full text: Pigments possessing the ability to confer high solar reflectance have received considerable attention in recent years. The inorganic class of NIR reflective pigments are mainly metal oxides and are primarily employed in two applications: (i) visual camouflage and (ii) reducing heat build up. More than half of the solar radiation consists of near-infrared radiation (52%), the remaining being 43% visible light and 5% ultraviolet radiation. Over heating due to solar radiation negatively affects comfort in the built environment and contributes substantially to electrical consumption for air conditioning and release of green house gases. A pigment which has strong reflections in the NIR region (780-2500 nm) can be referred to as a 'cool' pigment. However, most of the NIR reflective inorganic pigments particularly yellow (eg. cadmium yellow, lead chromate, chrome titanate yellow etc.) contain toxic metals and hence their consumption is being limited. Replacing ...
In order to study the intragenic profiles of active transcription, we determined the relative levels of active RNA polymerase II present at the 3′- and 5′-ends of 261 yeast genes by...Full Text Available
The temporal patterns of protein phosphorylation in the adrenal glomerulosa cell were analysed by two-dimensional electrophoresis after stimulation with 10 nM-angiotensin II or various agents [10 nM-12-O-tetradecanoylphorbol...Full Text Available
Silanization of the silica gel surface in the synthesis of silica gel polyamine composites uses (chloropropyl)-trichlorosilane (CPTCS). It is possible to substitute a molar fraction of reagent CPTCS with methyltrichlorosilane (MTCS), creating a mixed silane surface layer. Two types of silica gels were modified with a series of MTCS:CPTCS molar ratios. Solid-state CP/MAS 29Si and 13C NMR spectroscopies were used to evaluate the surface silane composition. Surface silane coverage was markedly improved for the resulting gels. When polyamines were grafted to the resultant MTCS:CPTCS silane layers, it was shown that the decrease in the number of propyl attachments to the polyamine resulted in increased quantities of ''free amines''. Optimum MTCS:CPTCS ratios were determined for three polyamines grafted onto one silica gel. A substantial free amine increase was observed for poly(allylamine) (PAA). Metal uptake studies show increases in ...
Silanization of the silica gel surface in the synthesis of silica gel polyamine composites uses (chloropropyl)-trichlorosilane (CPTCS). It is possible to substitute a molar fraction of reagent CPTCS with methyltrichlorosilane (MTCS), creating a mixed silane surface layer. Two types of silica gels were modified with a series of MTCS:CPTCS molar ratios. Solid-state CP/MAS 29Si and 13C NMR spectroscopies were used to evaluate the surface silane composition. Surface silane coverage was markedly improved for the resulting gels. When polyamines were grafted to the resultant MTCS:CPTCS silane layers, it was shown that the decrease in the number of propyl attachments to the polyamine resulted in increased quantities of ''free amines''. Optimum MTCS:CPTCS ratios were determined for three polyamines grafted onto one silica gel. A substantial free amine increase was observed for poly(allylamine) (PAA). Metal uptake studies show increases in ...
The spin-up problem of He II in a cylindrical container of infinite and finite height is considered on the basis of the Hall-Vinen-Bekarevich-Khalatnikov equations. The boundary conditions include the assumption of the generation of superfluid vorticity at the walls of the container. In the lowest order approximation with respect to viscosity, the problem is reduced to a Stefan problem for a single diffusion-type equation. Examples of solutions are given which show that the method used gives a good insight into the physical development of the spin-up flow.
Type II NAD(P)H:quinone oxidoreductases (NDH-2) catalyze the two-electron transfer from NAD(P)H to quinones, without any energy-transducing site. NDH-2 accomplish the turnover of NAD(P)H, regenerating...Full Text Available
It is shown that observations of the lithium isotope ratio in high surface temperature Population II stars may be critical to cosmological nucleosynthesis models. In particular, decaying particle scenarios as derived in some supersymmetric models may stand or fall with such observations. 18 references.
The theoretical evolution of a horizontal branch star of Population II is followed through the helium burning in the core phase and is compared with the results given by other investigators. The m- fluence of different physics and interpolation schemes in the opacity tables is discussed. Some thoughts are given on the explanation of the erratic period variations observed in some of the RR Lyrae variables in the globular clusters. (auth)
Experimental results are presented on the quasi-statistic polarization reversal and on the effect of high dc electric field on the behaviour of LiNH_4SO_4 and LiND_4SO_4 monocrystals, namely in the vicinity of the II-III phase transformation.
PurposeRTOG protocol 95-17 was a phase I/II trial to evaluate multi-catheter brachytherapy as the sole method of adjuvant breast radiotherapy for stage I/II breast...Full Text Available
A comparison was made of the advantages and disadvantages of two codes, SAND-II and FERRET, for determining the neutron flux spectrum and uncertainty from experimental dosimeter measurements as anticipated in the FFTF Reactor Characterization Program. This comparison involved an examination of the methodology and the operational performance of each code. The merits of each code were identified with respect to theoretical basis, directness of method, solution uniqueness, subjective influences, and sensitivity to various input parameters.
The answer to the title is ''NO''. The authors investigate the low energy particle spectra of type-II superstring theory after compactification to 4 dimensional space-time by means of the super Kac-Moody algebra as well as the twisted super Kac-Moody algebra. They show that there is no solution containing all of the particle contents in the standard model.
Several closely related Mn(II)-oxidizing alpha-Proteobacteria were isolated from very different marine environments: strain SI85-9A1 from the oxic/anoxic interface of a stratified...Full Text Available
The nature of binding of Ru(phen) 2+ (I), Ru(bipy) 2+ (II), Ru(terpy) 2+ (III) (phen = 1,10-phenanthroline, bipy 3 = 2,2'-bipyridyl, 3 terpy = 2,2'2," - 2 terpyridyl) to DNA, poly[d(G-C)] and poly[d(A-T)]...Full Text Available
This report summarizes the progress made on the development of an integrated multistage fluidized bed retorting process (KENTORT II) during the period of October 1, 1992 through September 30, 1993 under Cooperative Agreement No. DE-FC21-90MC27286 with the Morgantown Energy Technology Center, US Department of Energy. The KENTORT II process includes integral fluidized bed zones for pyrolysis, gasification, and combustion of the oil shale. The purpose of this program is to design and test the KENTORT II process at the 50-lb/hr scale. The PDU was assembled, instrumented and tested during this fiscal year. Along with the major activity of commissioning the 50-lb/hr retort, work was also completed in other areas. Basic studies of the cracking and coking kinetics of model compounds in a fixed bed reactor were continued. Additionally, as part of the effort to investigate niche market applications for KENTORT ...
The properties of the highest velocity ejecta of normal Type Ia supernovae (SNe Ia) are studied via models of very early optical spectra of 6 SNe. At epochs earlier than 1 week before maximum, SNe with a rapidly evolving Si II 6355 line velocity (HVG) have a larger photospheric velocity than SNe with a slowly evolving Si II 6355 line velocity (LVG). Since the two groups have comparable luminosities, the temperature at the photosphere is higher in LVG SNe. This explains the different overall spectral appearance of HVG and LVG SNe. However, the variation of the Ca II and Si II absorptions at the highest velocities (v >~ 20,000 km/s) suggests that additional factors, such as asphericity or different abundances in the progenitor white dwarf, affect the outermost layers. The C II 6578 line is marginally detected in 3 LVG SNe, suggesting that LVG undergo less intense burning. The ...
A series of NHC silver(I), mercury(II) and palladium(II) complexes, [(1,3-diethylbimy)6Ag4I3]I (2), [(1-benzyl-3-picolylbimy)Ag2Br2]n (3), [(1-benzyl-3-picolylbimy)HgI(CH2CN)]2 (4), {[(1-picolyl-3-npropylbimy)2Hg][Hg2I6]}n (5) and [(1,3-dipicolylbimy)PdCl]Cl (6), as well as one anionic complex [1,3-diethylbimidazolium]2[HgI4] (1) (bimy=benzimidazol-2-ylidene), have been prepared and characterized. Interestingly, a wind wheel-like Ag4I3 arrangement in 2 is formed, 1D polymeric chain containing 12-membered macrometallocycles and quadrangle Ag2Br2 units in 3 is generated, and the a-carbon atom of deprotonated acetonitrile ([CH2CN]-) in 4 participates in coordination with mercury(II) atom. In the crystal packings of complexes 1-6, 2D supramolecular layers or 3D supramolecular architectures are...
A number of amines can be employed for all volatile treatment (AVT) of steam generator (SG) systems of nuclear power reactors. These amines form complexes with Cu{sup 2+} and Ni{sup 2+} ions which come into water due to corrosion. The redox reactions of a number of Cu(II)-AVT amine complexes and the stability of the transient species formed have been studied by pulse radiolysis technique. Rate constants for the reaction of e{sub aq}{sup -} with a number of Cu(II)-amine complexes have been determined by following the decay of e{sub aq}{sup -} absorption. Stability of Cu(I)-amine complexes was studied by following the kinetics of the bleaching signal formed at the {lambda}{sub max} of the Cu(II) amine complex. Except for Cu(I)-triethanolamine complex all other Cu(I)-amine complexes were found to be stable. One-electron oxidation of Cu(II) amine complexes was studied using azidyl radicals for the oxidation ...
Coutinho MF, Encarnao M, Gomes R, da Silva Santos L, Martins S, Sirois-Gagnon D, Bargal R, Filocamo M, Raas-Rothschild A, Tappino B, Laprise C, Cury GK, Schwartz IV, Artigals O, Prata MJ, Alves S. Origin and spread of a common deletion causing mucolipidosis type II: insights from patterns of haplotypic diversity. Mucolipidosis II (ML II alpha/beta), or I-cell disease, is a rare genetic disease in which activity of the uridine diphosphate (UDP)-N-acetylglucosamine:lysosomal enzyme N-acetylglucosamine-1-phosphotransferase (GlcNAc-phosphotransferase) is absent. GlcNAc-phosphotransferase is a multimeric enzyme encoded by two genes, GNPTAB and GNPTG. A spectrum of mutations in GNPTAB has been recently reported to cause ML II alpha/beta. Most of these mutations were found to be private or rare. ...
We study the condensation of localized closed string tachyons in C{sup 3}/Z{sub N} non-supersymmetric noncompact orbifold singularities via renormalization group flows that preserve supersymmetry in the worldsheet conformal field theory and their interrelations with the toric geometry of these orbifolds. We show that for worldsheet supersymmetric tachyons, the endpoint of tachyon condensation generically includes 'geometric' terminal singularities (orbifolds that do not have any marginal or relevant Kahler blowup modes) as well as singularities in co-dimension two. Some of the various possible distinct geometric resolutions are related by flip transitions. For Type II theories, we show that the residual singularities that arise under tachyon condensation in various classes of Type II theories also admit a Type II GSO projection. We further show that Type II orbifolds entirely devoid of ...
Our studies have shown that endotoxin intratracheally instilled into the rat lung induces proliferation of alveolar type II cells. In that study, the alveolar type II cells. In that study, the alveolar type II cell hyperplasia occurred 2 d after instillation of endotoxin and persisted for a further 2 d. After hyperplasia, the lung remodeled and returned to a normal state within 24-48 h. Understanding the mechanisms involved in the remodeling process of this transient hyperplasia may be useful to identify molecular changes that are altered in neoplasia. The purpose of the present study was to corroborate induction of epithelial cell hyperplasia by endotoxin and to delineate mechanisms involved in tissue remodeling after endotoxin-induced alveolar type II cell hyperplasia. In conclusion, immonostaining with cyclin D1 and cytokeratin shows that endotoxin induced epithelial cell proliferation and resulted ...
Two overlapping cDNA clones encoding human DNA topoisomerase II were identified by two independent methods. In one, a human cDNA library in phage {lambda} was screened by hybridization with a mixed oligonucleotide probe encoding a stretch of seven amino acids found in yeast and Drosophila DNA topoisomerase II; in the other, a different human cDNA library in a {lambda}gt11 expression vector was screened for the expression of antigenic determinants that are recognized by rabbit antibodies specific to human DNA topoisomerase II. The entire coding sequences of the human DNA topoisomerase II gene were determined from these and several additional clones, identified through the use of the cloned human TOP2 gene sequences as probes. Hybridization between the cloned sequences and mRNA and genomic DNA indicates that the human enzyme is encoded by a single-copy gene. The location of the gene was mapped to ...
The ability of white-rot fungus, Pycnoporus sanguineus to adsorb copper (II) ions from aqueous solution is investigated in a batch system. The live fungus cells were immobilized into Ca-alginate gel to study the influence of pH, initial metal ions concentration, biomass loading and temperature on the biosorption capacity. The optimum uptake of Cu (II) ions was observed at pH 5 with a value of 2.76 mg/g. Biosorption equilibrium data were best described by Langmuir isotherm model followed by Redlich-Peterson and Freundlich models, respectively. The biosorption kinetics followed the pseudo-second order and intraparticle diffusion equations. The thermodynamic parameters enthalpy change (10.16 kJ/mol) and entropy change (33.78 J/mol K) were determined from the biosorption equilibrium data. The FTIR analysis showed that -OH, -NH, C-H, C=O, -COOH and C-N groups were involved in the biosorption of Cu (II) ions onto immobilized ...
... Astronomy & Space Biology Chemistry & Materials Computing Earth & Environment Education ... Materials Research Center at the University of Chicago, one of nearly 30 NSF-supported Materials ...
... of Award Costs (Schedule A), are free of material misstatement. An audit includes examining, on a ... support costs, materials and supplies, and the indirect costs. We found two material internal ...
International Patenting Trends in Advanced Materials: Ceramics (June 18, 1999) This report is the ... manufacturing, biotechnology, and advanced materials. Hypertext Format Portable Document Format ...
... s guides and "how-to" videos and other materials, and 7. Receive continuing support from GLOBE's ... and educational materials that result from international proposals in its materials and support ...
As adulterated and substituted Chinese medicinal materials are common in the market, therapeutic effectiveness of such materials cannot be guaranteed. Identification at species-, strain- and locality-levels,...Full Text Available
... curricula and prototypical instructional materials have been emphasized. The program has provided ... materials are adapted and implemented on a state-wide basis. The laboratory materials and the text ...
The biomedical and ecological interest for the microwave impact on the Earth biosphere is continuously increased since the industrial, military and communication activities strongly contribute to the electromagnetic stress of living bodies. In the next the authors present some of the main results obtained regarding the microwave exposure of various types of biological material: bacteria, fungi, young plant seedlings, dry seeds, animal tissues. The electromagnetic exposure was carried out in open space in well controlled environmental conditions by using 10.75 GHz/1 m W cm{sup -2} microwaves. Biochemical assays and cytogenetic tests have been carried out to reveal the changes induced post irradiation. The response of some pathogen bacteria, have been emphasized by means of turbidimetric measurements - the stimulatory effect being noticed at the level of the microbial population density (the stimulation of the human body microbial flora seems to be one of the side ...
In early 2004, the U.S. Department of Energy (DOE) Richland and Fluor Hanford requested technical assistance from the DOE Headquarters EM-23 Technical Assistance Program to provide a team of technical experts to develop recommendations for mending the In Situ Redox Manipulation (ISRM) Barrier in the 100-D Area of the Hanford Site in Washington State. To accommodate this request, EM-23 provided support to convene a group of technical experts from industry, a national laboratory, and a DOE site to participate in a 2 1/2-day workshop with the objective of identifying and recommending options to enhance the performance of the 100-D Area reactive barrier and of a planned extension to the northeast. This report provides written documentation of the team's findings and recommendations. In 1995, a plume of dissolved hexavalent chromium [Cr(VI)], which resulted from operation of the D/DR Reactors at the Hanford site, was discovered along the Columbia River shoreline and in the 100-D ...
This is the second revision of the ETDE/INIS Joint Thesaurus, including all updates up to September 2006. It contains 21 147 valid descriptors and 9 114 forbidden terms. The Joint Thesaurus contains the controlled terminology for indexing all information within the subject scopes of the International Nuclear Information System (INIS) and the Energy Technology Data Exchange (ETDE). The terminology is intended for use in subject descriptions for input or retrieval of information in these systems. The thesaurus is a terminological control device used in translating from the natural language of documents, indexers or users into a more constrained system language It is also a controlled and dynamic vocabulary of semantically and generically related terms which covers a specific domain of knowledge. The basic terminology in this thesaurus goes back to the 1969 edition of the EURATOM Thesaurus. The structure subsequently given to that terminology was the result of a systematic study performed ...
Dust detection and control in real time, represent one of the most challenging problem in all those environments where fine and ultrafine airborne particulate solids products are present. The presence of such products can be linked to several factors, often directly related and influenced by the working-production actions performed. Independently from the causes generating dust, airborne contaminants are an occupational problem of increasing interest as they are related to a wide number of diseases. In particular, airborne dusts are well known to be associated with several classical occupational lung diseases, such as the pneumoconiosis, especially at high levels of exposure. Nowadays there is also an increasing interest in other dust related diseases, from the most serious as cancer and asthma, to those related with allergies or irritation and other illnesses, also occurring at lower levels of exposure. Among the different critical factors influencing health risk for airborne dust ...
For heavy-ion beam driven inertial fusion ''liquid-protected'' reactor designs such as HYLIFE-II, a mixture of molten salts made of F{sup 10}, Li{sup -6}, Li{sup 7} and Be{sup 9} (called flibe) allows small chambers and final-focus magnets closer to the target with superconducting coils suffering higher radiation damage, though they can stand only a certain amount of energy deposited before quenching. This work has been primarily focusing on verifying that total energy deposited by fusion neutrons and induced gamma rays remain under such limit values and the final purpose is the optimization of the shielding of the magnetic lens system from the points of view of the geometrical configuration and of the physical nature of the materials adopted. The system is analyzed in terms of six geometrical models going from simplified up to much more realistic representations of a system of 192 beam lines, each focused by ...
Purpose/Objective: With the advent of computed tomography and magnetic resonance imaging, the three dimensional representation of the patient anatomy has become an invaluable resource for better diagnosis and delineation of the target volume and sensitive structures in radiation therapy. Although the therapeutic linear accelerator industry has made available highly sophisticated equipment, the aggressiveness in dose prescription and delivery has to be complimented by accurate dose computation methods. We have adopted a convolution/superposition algorithm for the calculation of absolute dose that fully accounts for the external shape and internal structure of the patient for photon treatment radiotherapy. In this paper, we will discuss the principles of the convolution algorithm and we will show how the computed dose compares to clinically relevant treatment techniques. Materials and Methods: A computer controlled data acquisition system and a water tank where used ...
This document is the Final Report for the project Introduccion de Mejoras Tecnologicas en el SISCOM II, or Improvements in SISCOM II Technology. It consists of a brief description of the activities carried out during the project, and several Annexes that explain in a deeper way each result. SISCOM II is the main telemetry system currently in use in the Spanish underground coal mining, but it was developed ten years ago and needed a technological update, which was the objective of this project. The aims of the project were: To develop Hardware and Software for the Out stations currently used (maintenance developments) To design new hardware and software, easier to use in the current and new applications of SISCOM II Both objectives were met, although not in the way originally intended. The main results were: In the field of old Out stations update: A new set of boards for the old Out stations was ...
The purpose of the current study was to evaluate the difference in prognostic factors between stage IB and II uterine cervical carcinoma patients treated with postoperative radiation therapy. Between May 1988 and May 1998, a total of 94 patients including 47 patients with stage IB and 47 patients with stage II uterine cervical carcinoma were treated with postoperative radiation therapy at Tokyo Metropolitan Komagome Hospital. All patients were treated with 10 MV X-rays using an anterior-posterior parallel opposed field which covered the whole pelvis. Fractionation was 2 Gy per day, five fractions per week, to a total dose of 50 Gy. The 5-year overall survival rates of stage IB and II were 89.4% and 79.3%, respectively. In multivariate analysis for all patients, lymph node status, histology, and surgical margin status were recognized as prognostic factors. Limited to stage IB patients, lymph node status was the only ...
... Tokyo Report: Japanese Government Budget for Materials R&D Date: 6/17/97 The National Science ... Graded Materials Area coordinator: Dr. Toshio Hirai, Professor, Institute for Materials Research ...
... impact criterion, as demonstrated by the materials research community. These include training ... designing new materials or new processing/fabrication routes to existing materials; exploring and ...
... of new construction materials; and the behavior of infrastructure materials and structural ... polymers, reinforcing materials, wood and biodegradable structural materials; scale effects from ...
The US National Energy Policy of 2001 advocated the development of advanced fuel and fuel cycle technologies that are cleaner, more efficient, less waste-intensive, and more proliferation resistant. The need for advanced fuel development is emphasized in on-going DOE-supported programs, e.g., Global Nuclear Energy Initiative (GNEI), Advanced Fuel Cycle Initiative (AFCI), and GEN-IV Technology Development. The Directorates of Energy & Environment (E&E) and Chemistry & Material Sciences (C&MS) at Lawrence Livermore National Laboratory (LLNL) are interested in advanced fuel research and manufacturing using its multi-disciplinary capability and facilities to support a design concept of a small, secure, transportable, and autonomous reactor (SSTAR). The E&E and C&MS Directorates co-sponsored this Laboratory Directed Research & Development (LDRD) Project on Mono-Uranium Nitride Fuel Development for SSTAR and Space Applications. ...
Alloy 800 and Alloy 600 are well known for their resistance to corrosion in an aqueous medium at high pressure and temperature, for which they have been widely used for more than 3 decades in different structural components of water refrigerated nuclear reactors, especially as material for the steam generator tubes (SG) in these nuclear plants. The SG tubes in the Atucha I and Embalse Nuclear Plants are made with Alloy 800. The speed of corrosion of these materials in a reactor's refrigerant medium, while very small is perfectly measurable and can be described by parabolic or logarithmic type kinetics. In other words this speed is high in the first states of growth during the formation of a protective oxide film but then drops to almost stationary values. One characteristic of these films is the formation of a double layer (or duplex): i) an internal adhering layer, of approximately constant thickness, formed by small microcrystals (#<=#0.05 ...
The CDF II eXtremely Fast Tracker (XFT) is the trigger processor which reconstructs charged particle tracks in the CDF II central outer tracking chamber. The XFT tracks are also extrapolated to the electromagnetic calorimeter and muon chambers and are associated to electromagnetic clusters and muon stubs to generate trigger electron and muon candidates. The steady increase of the Tevatron instantaneous luminosity and the resulting higher occupancy of the chamber demanded an upgrade of the original system, which performed tracking only in the transverse plane of the chamber and was consequently affected by a significant level of fake tracks. In the upgraded XFT, tracking is reinforced by using additional data from the stereo layers of the chamber to reduce the level of fake tracks and to perform three-dimensional track reconstruction. A review of this upgrade is presented.
Feasibility Study-II examined a high-performance Neutrino Factory providing 1 x 10{sup 20} neutrinos per year aimed at a long-baseline detector. The Study was sponsored jointly by BNL and the Neutrino Factory and Muon Collider Collaboration ration (MC) and is based on a 1 MW proton driver operating at 24 GeV, i.e., an upgraded version of the AGS accelerator. Compared with the earlier FNAL-sponsored study (Feasibility Study-I), there is a sixfold improvement in performance. Here we describe details of the implementation of Study-II concepts and discuss their efficacy. Alternative approaches that will be pursued in follow-on R and D activities are also described briefly.
Cu(II)-ATSM continues to be investigated, both in the laboratory and in the clinic, as a tumor hypoxia imaging agent. However, meaningful interpretation of these images requires a more complete understanding of the mechanism by which the tracer is trapped within the cell. Cu(II)-ATSM is a simple molecule and its biochemical interaction with cells is similarly simple, mainly based upon redox chemistry. Here we suggest that the trapping mechanism is biphasic. The first phase is a reduction/oxidation cycle involving thiols and molecular oxygen. This can be followed by interaction with proteins in the mitochondria leading to more permanent retention of the tracer. The uptake mechanism is complicated by this second step because of the changes in the cell resulting from hypoxia, such as an incre...
The distribution of the alkaline earth elements strontium and barium between the solid phases of phosphates of transition elements of group 4 and chloride melts was studied. The distribution coefficients of strontium and barium were found at T = 700-800/sup 0/C. Phosphates of the type NaM/sub 2//sup (IV)/(PO/sub 4/)/sub 3/, where M/sub (IV)/ represents titanium, zirconium, and hafnium, were used as the solid phases. It was established that there is an enrichment of the precipitates with the distributed components. The distribution coefficient depends on the nature of the solid phase and the temperature. It was suggested that M/sup (II)/ x M/sub 4//sup (IV)/(PO/sub 4/)/sub 6/ is formed in processes of distribution, where M/sup (II)/ represents Sr, Ba.
Raman and infrared spectroscopy of para-H{sub 2} to pressures in excess of 200GPa and to 8K using new ultrapure synthetic diamond anvils reveals numerous new vibrational excitations in the three high-pressure phases. Highly resolved Raman-active librons indicate differences in orientational ordering between phasesII and III, including evidence for changes within phaseII. The librons in phaseIII are strongly pressure dependent and reflect a substantial increase in ordering with pressure. Multiple vibrons in all three phases (I, II, and III) are observed. The results place new bounds on predicted crystal structures and dynamics of the dense molecular solid. {copyright} {ital 1997} {ital The American Physical Society}
The EXAFS spectra of the platinum(III) complexes Pt/sub 4/(OAc)/sub 10/(OH)/sub 2/ (I) and Pt/sub 4/ (OAc)/sub 4/(OH)/sub 8/(H/sub 2/O)/sub 2/ (II) have been investigated. It has been found by a curve-fitting method and with the aid of Fourier transformations that the shortest Pt-Pt distances are 2.61 A in complex I and 2.36 and 2.6 A in II. The values of the bond lengths obtained are consistent with the molecular structures proposed for complexes I and II, which contain skeletons of four platinum atoms in the form of a square or a rectangle, as well as with the known literature data on the lengths of Pt-Pt bonds in Pt(III) complexes.
Purpose Evaluation of the all-trans retinoic acid (t-RA) effects on in vitro maturation (IVM) and in vitro fertilization (IVF) of immature mouse oocytes in the presence and absence of granulosa cell monolayer. Methods Denuded oocytes isolated from mice ovaries and matured in IVM medium alone (Control I), IVM medium in the presence of granulosa cells (Control II), IVM medium with t-RA (Experimental I) and IVM medium simultaneously with t-RA and granulosa cells (Experimental II). After 24?h, matured oocytes were fertilized in T6 medium and their development was followed until the blastocyst stage. Metaphase II oocytes ploidy were evaluated by chromosome counting. Results The t-RA group compared to the control groups showed no obvious abnormalities. Additionally maturation and embryo developm...
The synthesis, characterization, and some analytical applications of a new triazine resin are described. Separation of group IB, IIB, VIB, and VIIB metal ions from group VIII metal ions is achieved by this PDT-4 resin. Calcium(II) and magnesium(II) are taken up at pH = 6, 0.1 M acetate and are eluted at pH = 6, 0.1 M sodium nitrate. Copper(II) is retained at pH = 6, 0.1 M acetate and pH = 1 hydrochloric acid and is eluted subsequently by 5 M perchloric acid. Molybdenum(VI) is sorbed selectively from 0.1 N sulfuric acid or hydrochloric acid and is eluted in a tight band by 0.1 N sodium hydroxide. Numerous rapid column chromatographic separations are reported using this new resin, including analysis of NBS standard samples.
We study the localized tachyon condensation of non-supersymmetric orbifold backgrounds in their mirror Landau-Ginzburg picture. We first show that the R-charges of chiral primaries increase under the process of condensing the tachyon in the same chiral ring. Then, utilizing the existence of four copies of (2,2) worldsheet supersymmetry, we show that the minimal tachyon mass in twisted sectors increases in CFT and type 0 string and it plays the role of the c-function of the twisted sectors. We also study the GSO projection in detail and show that type II decays to only to type II while type 0 can mix with type 0 and II under the RG-flow.
Summary Background Sorafenib is an oral multikinase inhibitor that blocks cell proliferation via the ERK pathway and angiogenesis via the VEGF pathway. This phase II trial was conducted to determine the efficacy and tolerability of sorafenib for the treatment of patients with metastatic urothelial cancer (UC) who had not had prior chemotherapy for advanced disease. Patients and Methods Seventeen chemo-na?ve UC patients with adequate performance status and organ function were treated with sorafenib 400?mg twice daily on a continuous basis until progression or unacceptable toxicity. The primary endpoint was objective tumor response rate as measured by RECIST criteria. Secondary endpoints included rate of prolonged stable disease (>3?months), time to progression, median and 1?yr survival and ...
... The Effect of the Temperature to Which the Material is Heated on the Process of Formation of Intermetallic Compounds in Magnetic Pulse Welding,. ...
... and Security..........................13 Materials Science ... hybrid system theory, Internet analysis, materials science, mixing, physiology, iterative control ...
... many intriguing new possibilities in the materials sciences. Or consider solitons, a mathematical ... point out that advanced instrumentation, new materials, novel production methods, and efficient ...
Sensory rhodopsins (SRs) belong to a subfamily of heptahelical transmembrane proteins containing a retinal chromophore. These photoreceptors mediate the cascade of vision in animal eyes and phototaxis...Full Text Available
The Ty transposable elements of Saccharomyces cerevisiae form a heterogeneous family within which two broad structural classes (I and II) exist. The two classes differ by two large substitutions and...Full Text Available
Molecular Misreading (MM) is the inaccurate conversion of genomic information into aberrant proteins. For example, when RNA polymerase II transcribes a GAGAG motif it synthesizes at low frequency RNA...Full Text Available
... NE Mall Room B-607, EPA Headquarters, 401 M ... formally adopted and initiated a joint strategy for ... CLI kick-off Partner and Task Force meeting. ...
Highly polymorphic genes with central roles in lymphocyte mediated immune surveillance are grouped together in the major histocompatibility complex (MHC) in higher vertebrates. Generally, across vertebrate...Full Text Available
Thin film solar cells and solar cell testing - photovoltaic cells, radiation damage to cadmium sulfide solar cells, and airplane testing of solar cells
The article is divided into three sections: (i) an overview of the main ethical models in public health (theoretical foundations); (ii) a summary of several published frameworks for public health ethics...Full Text Available
The effect of Escherichia coli lipopolysaccharide (LPS) on the expression of major histocompatibility complex (MHC) class II molecules by bovine mammary macrophages was examined. The ability of LPS-treated...Full Text Available
The world's oceans contain a complex mixture of micro-organisms that are for the most part, uncharacterized both genetically and biochemically. We report here a metagenomic study of the marine planktonic...Full Text Available
The clinical management of adults with low-grade gliomas (LGGs) remains a challenge. There is no curative treatment, and management of individual patients is a matter of deciding optimal timing as well...Full Text Available
Feb 23, 2011 ... THEMIS-D: The Solid State Telescope (SST) measures the incoming ... Each single sensor covers an angle of 36 degrees. .... The five small satellites were launched together on a Delta II rocket and they carry identical ...
Six related Staphylococcus phages spontaneously produced various abnormal head and tail structures: (i) giant capsids which were tailed and apparently contained nucleic acid; (ii) regular and irregular...Full Text Available
Sedentary adult males with spinal lesions, all habitual wheelchair users, were allocated to exercise (n = 11) and control (n = 4) groups. A Cybex II dynamometer was used to assess peak power, average...Full Text Available
Spectral line intensity data are presented for ionized hydrogen regions in the giant spiral galaxy M101. The influence of interstellar extinction is assessed and electron temperatures of the gas clouds are derived.
THEMIS-A: The Solid State Telescope (SST) measures the incoming intensity ... units (heads), each SST unit has two pairs of opposing ion and electron sensors. .... The five small satellites were launched together on a Delta II rocket and they ...
The planned spallation source can be of considerable significance for biomedical basic research and for clinically relevant diagnostic and therapeutic applications. The following gives a brief description and explanations for its possible use in clinical medicine: I. Treatment of Malignant Tumors II. Production of Isotopes for Biochemical Investigations in Living Organisms for Diagnostic Purposes.
We designed a multicenter study to compare tobramycin/clindamycin to imipenem/cilastatin for intra-abdominal infections. We included the Acute Physiology and Chronic Health Evaluation (APACHE II) index...Full Text Available
SUMMARYReplication timing is frequently discussed superficially in terms of its relationship to transcriptional activity via chromatin structure. However, so little is known about...Full Text Available
The results of the radon concentration measurements in dwellings in Belgrade were shown in this paper. The measurements were done using long term method with diffusion cups equipped with solid state nuclear track detector LR-115-II or CR-39. (author).
The Gordon Research Conference (GRC) on ROCK DEFORMATION was held at II Ciocco from 5/19/02 thru 5/24/02. Emphasis was placed on current unpublished research and discussion of the future target areas in this field.
Human longevity is in part genetically determined, and the insulin/IGF-1 signal transduction (IIS) pathway has consistently been implicated. In humans, type 2 diabetes is a frequent disease that results...Full Text Available
PurposePlatinum and taxane compounds have demonstrated activity in uterine carcinosarcoma (malignant mixed Mullerian tumor). Ifosfamide plus paclitaxel is the regimen with established...Full Text Available
A study of the joint evolution of the normal- and neutron-star components of massive binaries opens with a classification scheme and the analytic expressions to be applied in Paper II for computer simulation of the observable properties of such systems.
Endosomal sorting complexes required for transport (ESCRTs) are heteromeric protein complexes required for multivesicular body (MVB) morphogenesis. ESCRTs I, II, III and III-associated are ubiquitous...Full Text Available
Obesity and metabolic syndrome result from excess calorie intake and genetic predisposition and are mechanistically linked to type II diabetes and accelerated body aging; abnormal nutrient and insulin...Full Text Available
SummaryThe general transcription factor TFIID is a large multi-subunit complex required for the transcription of most protein-encoding genes by RNA polymerase II. Taking advantage...Full Text Available
Type II collagen-induced arthritis (CIA) in mice is an autoimmune experimental model for rheumatoid arthritis. Susceptibility to CIA is associated with certain major histocompatibility complex class...Full Text Available
Mammals possess multiple insulin-like growth factor (IGF) binding proteins (IGFBPs), and related proteins, that modulate the activity of insulin/IGF signalling (IIS), a conserved neuroendocrine signalling...Full Text Available
Rationale: Human data suggest that the incidence of acute lung injury is reduced in patients with type II diabetes mellitus. However, the mechanisms by which diabetes confers protection...Full Text Available
The importance of a properly functioning and well-balanced immune system for maintaining health has become strikingly evident over the past decades. Roughly since World War II, there has been an apparent...Full Text Available
Several examples of the 14-membered, para-bridged ring system of the cyclopeptide alkaloids have been synthesized via an active ester cyclization. The yield of monomeric cyclopeptide varied from 1 to 33% and was affected by the amino acid substitution pat...
Microarray data has a high dimension of variables but available datasets usually have only a small number of samples, thereby making the study of such datasets interesting and challenging. In the task...Full Text Available
We present results of near--IR long-slit spectroscopy in the J and K bands of the Seyfert 2 galaxies NGC 2110 and Circinus, investigating the gaseous distribution, excitation, reddening and kinematics. In NGC 2110, the emission line ratio [FeII]/Pa beta increases towards the nucleus (to ~ 7). The nuclear [Fe II]1.257 (microns) and Pa beta lines are broader (FWHM ~ 500 km/s) than the H2 (2.121) line (FWHM ~ 300 km/s). Both these results suggest that shocks, driven by the radio jet, are an important source of excitation of [Fe II]. The H2 excitation appears to be dominated by X-rays from the nucleus. In Circinus, both [FeII]/Pa beta and H2/Br gamma decrease from ~ 2 at 4 arcsec from the nucleus to nuclear values of ~ 0.6 and ~ 1, respectively, suggesting that the starburst dominates the nuclear excitation, while the AGN dominates the excitation further out (r > 2 arcsec). For both galaxies, the gaseous ...
Purpose.The hypothesis that drivers with homonymous hemianopia (HH) would take a lane position that increased the safety margin on their blind side was tested with a driving simulator.Methods.Twelve...Full Text Available
Systemic administration of lipopolysaccharide (LPS), which causes endotoxemia and systemic inflammation, has been reported to induce expression of the gene for type II inducible nitric oxide synthase...Full Text Available
Realization that dental caries is a reversible, dynamic biochemical event at a micron level has changed the way the profession recognizes the caries disease and the caries lesion. The diagnosis of dental...Full Text Available
BackgroundThe rate of emergence of human pathogens is steadily increasing; most of these novel agents originate in wildlife. Bats, remarkably, are the natural reservoirs of many...Full Text Available
This report documents the operation, maintenance, calibration, data acquisition and data reduction at the Chalk Point Meteorological Station for the period November 15, 1978 through November 15, 1979. Climatological data summaries for each month and calib...
Benzodiazepine withdrawal anxiety is associated with potentiation of α-amino-3-hydroxy-5-methyl-4-isoxazolepropionate receptor (AMPAR) currents in hippocampal CA1 pyramidal...Full Text Available
BackgroundThere is no consensus as to the prognostic model for brachytherapy of tongue carcinoma. This study was designed to evaluate the prognostic factors for local control based...Full Text Available
Alterations in basement membrane components, notably proteoglycans, in a rat model of polycystic kidney disease have been investigated. Rats were fed phenol II (2-amino-4-hydroxyphenyl-5-phenyl thiazole)...Full Text Available
This report made for the Swiss Federal Office of Energy (SFOE) discusses the conception, planning and construction of an easy-to-operate pilot heating plant that uses chicken litter as its fuel. The plant, which is installed at a chicken farm in Boesingen, Switzerland, produces 250 - 350 kW and not only supplies heat for two chicken sheds and two households, but also provides energy for a drying plant in summer. The results of measurements made on emissions are discussed and, within the framework of an eco-balance analysis, comparisons are made between the direct use of the droppings as manure or as a fuel. The cost-effectiveness of the plant is examined and the influence of plant size and other factors discussed. Further, legal questions concerning the use of chicken litter as a fuel for heating installations are discussed; the use of the droppings as a fuel is not foreseen in the legislation concerning water protection and airborne emissions of pollutants. Although normally this type ...
The protein kinase CK2 (formerly casein kinase II) is thought to be involved in light-regulated gene expression in plants because...Full Text Available
Pharmacologic or genetic deletion of components of the renin-angiotensin system leads to postnatal kidney injury, but the roles of these components in kidney development are unknown. To test the hypothesis...Full Text Available
PurposeWe previously reported a randomized phase II clinical trial combining a poxvirus-based vaccine encoding PSA with radiotherapy in patients with localized prostate...Full Text Available
...capacity, and ownership of all planned and existing onshore pipelines, storage facilities, refineries, petrochemical...will be served by the port, including: (i) Onshore pipelines; (ii) Storage facilities; (iii)...
...competent person shall inspect haulage equipment before each shift. (ii...used. (2) Powered mobile haulage equipment shall have suitable means of... (3)(i) Power mobile haulage equipment, including trains, shall...