40 CFR 63.1105 - Transfer racks.

Code of Federal Regulations, 2011 CFR

2011-07-01

... manner as a material that fulfills the same function in that process; (ii) Transformed by chemical reaction into materials that are not HAP; (iii) Incorporated into a product; and/or (iv) Recovered. (4...

40 CFR 63.1105 - Transfer racks.

Code of Federal Regulations, 2012 CFR

2012-07-01

... manner as a material that fulfills the same function in that process; (ii) Transformed by chemical reaction into materials that are not HAP; (iii) Incorporated into a product; and/or (iv) Recovered. (4...

40 CFR 63.1105 - Transfer racks.

Code of Federal Regulations, 2013 CFR

2013-07-01

... manner as a material that fulfills the same function in that process; (ii) Transformed by chemical reaction into materials that are not HAP; (iii) Incorporated into a product; and/or (iv) Recovered. (4...

Heavy metals adsorption by novel EDTA-modified chitosan-silica hybrid materials.

PubMed

Repo, Eveliina; Warchoł, Jolanta K; Bhatnagar, Amit; Sillanpää, Mika

2011-06-01

Novel adsorbents were synthesized by functionalizing chitosan-silica hybrid materials with (ethylenediaminetetraacetic acid) EDTA ligands. The synthesized adsorbents were found to combine the advantages of both silica gel (high surface area, porosity, rigid structure) and chitosan (surface functionality). The Adsorption potential of hybrid materials was investigated using Co(II), Ni(II), Cd(II), and Pb(II) as target metals by varying experimental conditions such as pH, contact time, and initial metal concentration. The kinetic results revealed that the pore diffusion process played a key role in adsorption kinetics, which might be attributed to the porous structure of synthesized adsorbents. The obtained maximum adsorption capacities of the hybrid materials for the metal ions ranged from 0.25 to 0.63 mmol/g under the studied experimental conditions. The adsorbent with the highest chitosan content showed the best adsorption efficiency. Bi-Langmuir and Sips isotherm model fitting to experimental data suggested the surface heterogeneity of the prepared adsorbents. In multimetal solutions, the hybrid adsorbents showed the highest affinity toward Pb(II). Copyright © 2011 Elsevier Inc. All rights reserved.

Microcomputer Applications for Health Care Professionals. Volume II. Curriculum Improvement Project. Region II.

ERIC Educational Resources Information Center

Bruce, Lucy

This volume is one of three in a self-paced computer literacy course that gives allied health students a firm base of knowledge concerning computer usage in the hospital environment. It also develops skill in several applications software packages. Volume II contains materials for three one-hour courses on word processing applications, spreadsheet…

Surface adsorption of poisonous Pb(II) ions from water using chitosan functionalised magnetic nanoparticles.

PubMed

Christopher, Femina Carolin; Anbalagan, Saravanan; Kumar, Ponnusamy Senthil; Pannerselvam, Sundar Rajan; Vaidyanathan, Vinoth Kumar

2017-06-01

In this study, chitosan functionalised magnetic nano-particles (CMNP) was synthesised and utilised as an effective adsorbent for the removal of Pb(II) ions from aqueous solution. The experimental studies reveal that adsorbent material has finer adsorption capacity for the removal of heavy metal ions. Parameters affecting the adsorption of Pb(II) ions on CMNP, such as initial Pb(II) ion concentration, contact time, solution pH, adsorbent dosage and temperature were studied. The adsorption equilibrium study showed that present adsorption system followed a Freundlich isotherm model. The experimental kinetic studies on the adsorption of Pb(II) ions exhibited that present adsorption process best obeyed with pseudo-first order kinetics. The maximum monolayer adsorption capacity of CMNP for the removal of Pb(II) ions was found to be 498.6 mg g -1 . The characterisation of present adsorbent material was done by FTIR, energy disperse X-ray analysis and vibrating sample magnetometer studies. Thermodynamic parameters such as Gibbs free energy (Δ G °), enthalpy (Δ H °) and entropy (Δ S °) have declared that the adsorption process was feasible, exothermic and spontaneous in nature. Sticking probability reported that adsorption of Pb(II) ions on CMNP was favourable at lower temperature and sticking capacity of Pb(II) ions was very high.

Hierarchically Superstructured Prussian Blue Analogues: Spontaneous Assembly Synthesis and Applications as Pseudocapacitive Materials

DOE PAGES

Yue, Yanfeng; Zhang, Zhiyong; Binder, Andrew J.; ...

2014-11-10

Hierarchically superstructured Prussian blue analogues (hexa- conventional hybrid graphene/MnO 2 nanostructured textiles. cyanoferrate, M = Ni II, Co II and Cu II) are synthesized through Because sodium or potassium ions are involved in energy stor- a spontaneous assembly technique. In sharp contrast to mac- age processes, more environmentally neutral electrolytes can roporous-only Prussian blue analogues, the hierarchically su- be utilized, making the superstructured porous Prussian blue perstructured porous Prussian blue materials are demonstrated analogues a great contender for applications as high-per- to possess a high capacitance, which is similar to those of the formance pseudocapacitors.

Agricultural Construction Volume II. Oxy-Gas and Other Cutting/Welding Processes. Woodworking, Metals, Finishing. Instructor's Guide.

ERIC Educational Resources Information Center

Admire, Myron; Maricle, Gary

This guide contains instructor's materials for teaching a secondary agricultural construction course consisting of instructional units on oxy-gas and other cutting and welding processes (10 lessons), woodworking (6 lessons), metals (10 lessons), and finishing (4 lessons). The materials for each unit include student objectives, a list of…

Blade System Design Study. Part II, final project report (GEC).

DOE Office of Scientific and Technical Information (OSTI.GOV)

Griffin, Dayton A.

2009-05-01

As part of the U.S. Department of Energy's Low Wind Speed Turbine program, Global Energy Concepts LLC (GEC)1 has studied alternative composite materials for wind turbine blades in the multi-megawatt size range. This work in one of the Blade System Design Studies (BSDS) funded through Sandia National Laboratories. The BSDS program was conducted in two phases. In the Part I BSDS, GEC assessed candidate innovations in composite materials, manufacturing processes, and structural configurations. GEC also made recommendations for testing composite coupons, details, assemblies, and blade substructures to be carried out in the Part II study (BSDS-II). The BSDS-II contract periodmore » began in May 2003, and testing was initiated in June 2004. The current report summarizes the results from the BSDS-II test program. Composite materials evaluated include carbon fiber in both pre-impregnated and vacuum-assisted resin transfer molding (VARTM) forms. Initial thin-coupon static testing included a wide range of parameters, including variation in manufacturer, fiber tow size, fabric architecture, and resin type. A smaller set of these materials and process types was also evaluated in thin-coupon fatigue testing, and in ply-drop and ply-transition panels. The majority of materials used epoxy resin, with vinyl ester (VE) resin also used for selected cases. Late in the project, testing of unidirectional fiberglass was added to provide an updated baseline against which to evaluate the carbon material performance. Numerous unidirectional carbon fabrics were considered for evaluation with VARTM infusion. All but one fabric style considered suffered either from poor infusibility or waviness of fibers combined with poor compaction. The exception was a triaxial carbon-fiberglass fabric produced by SAERTEX. This fabric became the primary choice for infused articles throughout the test program. The generally positive results obtained in this program for the SAERTEX material have led to its being used in innovative prototype blades of 9-m and 30-m length, as well as other non-wind related structures.« less

Treatment of model solutions and wastewater containing selected hazardous metal ions using a chitin/lignin hybrid material as an effective sorbent.

PubMed

Bartczak, Przemysław; Klapiszewski, Łukasz; Wysokowski, Marcin; Majchrzak, Izabela; Czernicka, Weronika; Piasecki, Adam; Ehrlich, Hermann; Jesionowski, Teofil

2017-12-15

A chitin/lignin material with defined physicochemical and morphological properties was used as an effective adsorbent of environmentally toxic metals from model systems. Particularly significant is its use in the neutralization of real industrial wastes. The ions Ni 2+ , Cu 2+ , Zn 2+ and Pb 2+ were adsorbed on the functional sorbent, confirming the high sorption capacity of the newly obtained product, primarily due to the presence on its surface of numerous active functional groups from the component biopolymers. The kinetics of the process of ion adsorption from model solution were investigated, and the experimental data were found to fit significantly better to a type 1 pseudo-second-order kinetic model, as confirmed by the high correlation coefficient of 0.999 for adsorption of both nickel(II) copper(II) zinc(II) and lead(II) ions. The experimental data obtained on the basis of adsorption isotherms corresponded to the Langmuir model. The sorption capacity of the chitin/lignin material was measured at 70.41 mg(Ni 2+ )/g, 75.70 mg(Cu 2+ )/g, 82.41 mg(Zn 2+ )/g and 91.74 mg(Pb 2+ )/g. Analysis of thermodynamic parameters confirmed the endothermic nature of the process. It was also shown that nitric acid is a very effective desorbing (regenerating) agent, enabling the chitin/lignin material to be reused as an effective sorbent of metal ions. The sorption abilities of the chitin/lignin system with respect to particular metal ions can be ordered in the sequence Ni 2+

SCALE UP OF CERAMIC WASTE FORMS FOR THE EBR-II SPENT FUEL TREATMENT PROCESS

DOE Office of Scientific and Technical Information (OSTI.GOV)

Matthew C. Morrison; Kenneth J. Bateman; Michael F. Simpson

2010-11-01

ABSTRACT SCALE UP OF CERAMIC WASTE FORMS FOR THE EBR-II SPENT FUEL TREATMENT PROCESS Matthew C. Morrison, Kenneth J. Bateman, Michael F. Simpson Idaho National Laboratory, P.O. Box 1625, Idaho Falls, ID 83415 The ceramic waste process is the intended method for disposing of waste salt electrolyte, which contains fission products from the fuel-processing electrorefiners (ER) at the INL. When mixed and processed with other materials, the waste salt can be stored in a durable ceramic waste form (CWF). The development of the CWF has recently progressed from small-scale testing and characterization to full-scale implementation and experimentation using surrogate materialsmore » in lieu of the ER electrolyte. Two full-scale (378 kg and 383 kg) CWF test runs have been successfully completed with final densities of 2.2 g/cm3 and 2.1 g/cm3, respectively. The purpose of the first CWF was to establish material preparation parameters. The emphasis of the second pre-qualification test run was to evaluate a preliminary multi-section CWF container design. Other considerations were to finalize material preparation parameters, measure the material height as it consolidates in the furnace, and identify when cracking occurs during the CWF cooldown process.« less

Structural, Electronic, and Electrochemical Properties of LixCo[Fe(CN)6]0.902.9H2O

NASA Astrophysics Data System (ADS)

Takachi, Masamitsu; Matsuda, Tomoyuki; Moritomo, Yutaka

2013-04-01

Prussian blue analogues with jungle-gym-type structure are promising candidates for cathode materials of the lithium-ion secondary battery (LIB). Here, we investigated the structural, electronic, and electrochemical properties of cobalt hexacyanoferrate, LixCo[Fe(CN)6]0.902.9H2O, against Li concentration (x). The capacity (= 139 mAh/g) of the thin-film electrode was close to the ideal value (= 132 mAh/g) for the two-electron reaction. The discharge curve exhibits three plateaus, i.e., plateaus I, II, and III. The material exhibits a first-order phase transition accompanied by significant volume expansion by 7% at the boundary between plateaus II and III. Ex situ X-ray absorption spectroscopy (XAS) indicates that the discharge processes of plateaus I, II, and III are ascribed to the reduction processes of Fe3+, Co3+, and Fe3+, respectively. The rate (r) and cycle (n) dependence of the electrode performance will be discussed in terms of the reduction processes.

Fabrication of the tea saponin functionalized reduced graphene oxide for fast adsorptive removal of Cd(II) from water

NASA Astrophysics Data System (ADS)

Li, Zhigang; Liu, Zhifeng; Wu, Zhibin; Zeng, Guangming; Shao, Binbin; Liu, Yujie; Jiang, Yilin; Zhong, Hua; Liu, Yang

2018-05-01

A novel graphene-based material of tea saponin functionalized reduced graphene oxide (TS-RGO) was synthesized via a facil thermal method, and it was characterized as the absorbent for Cd(II) removal from aqueous solutions. The factors on adsorption process including solution pH, contact time, initial concentration of Cd(II) and background electrolyte cations were studied to optimize the conditions for maximum adsorption at room temperature. The results indicated that Cd(II) adsorption was strongly dependent on pH and could be strongly affected by background electrolytes and ionic strength. The optimal pH and required equilibrium time was 6.0 and 10 min, respectively. The Cd(II) removal decreased with the presence of background electrolyte cations (Na+ < Ca2+ < Al3+). The adsorption kinetics of Cd(II) followed well with the pseudo-second-order model. The adsorption isotherm fitted well to the Langmuir model, indicating that the adsorption was a monolayer adsorption process occurred on the homogeneous surfaces of TS-RGO. The maximum monolayer adsorption capacity was 127 mg/g at 313 K and pH 6.0. Therefore, the TS-RGO was considered to be a cost-effective and promising material for the removal of Cd(II) from wastewater.

IUE observations of stars in the neighborhood of the Lambda Orionis nebula

NASA Technical Reports Server (NTRS)

Bergoffen, Martin J.; Van Buren, Dave

1988-01-01

Results are presented from an IUE archive study of five stars along the line of sight towards the Lambda Ori H II region. H I, Fe II, Si II, and Mn II column densities have been found using a profile-fitting technique for H I and the curve-of-growth method for the ions. HD 36861 and HD 36822 lie at or near the center of the H II region, while HD 35468 and HD 37490 are imbedded in the dense neutral shell surrounding the H II region. HD 38899 is a foreground star. The depletion factors in the gas of this nebula are indicative of some shock processing of the material along these lines of sight. This processing probably occurred in the early stages of the nebula's evolution.

40 CFR 65.144 - Fuel gas systems and processes to which storage vessel, transfer rack, or equipment leak...

Code of Federal Regulations, 2010 CFR

2010-07-01

...; (ii) Transformed by chemical reaction into materials that are not regulated materials; (iii... section for a storage vessel, the owner or operator shall prepare a design evaluation (or engineering...

49 CFR 236.1009 - Procedural requirements.

Code of Federal Regulations, 2014 CFR

2014-10-01

... fraud; (ii) Potentially invalidated assumptions determined as a result of in-service experience or one... inspect processes, procedures, facilities, documents, records, design and testing materials, artifacts, training materials and programs, and any other information used in the design, development, manufacture...

Automotive Manufacturing Processes. Volume II - Manufacturing Processes for Passive Restraint Systems

DOT National Transportation Integrated Search

1981-02-01

Extensive material substitution and resizing of the domestic automotive fleet, as well as the introduction of new technologies, will require major changes in the techniques and equipment used in the various manufacturing processes employed in the pro...

Focused electron beam induced deposition of pure SIO II

NASA Astrophysics Data System (ADS)

Perentes, Alexandre; Hoffmann, Patrik; Munnik, Frans

2007-02-01

Focused electron beam induced processing (FEBID) equipments are the "all in one" tools for high resolution investigation, and modification of nano-devices. Focused electron beam induced deposition from a gaseous precursor usually results in a nano-composite sub-structured material, in which the interesting material is embedded in an amorphous carbonaceous matrix. Using the Hydrogen free tetraisocyanatosilane Si(NCO) 4 molecule as Si source, we show how a controlled oxygen flux, simultaneously injected with the precursor vapors, causes contaminants to vanish from the FEB deposits obtained and leads to the deposition of pure SiO II. The chemical composition of the FEBID material could be controlled from SiC IINO 3 to SiO II, the latter containing undetectable foreign element contamination. The [O II] / [TICS] ratio needed to obtain SiO II in our FEB deposition equipment is larger than 300. The evolution of the FEBID material chemical composition is presented as function of the [O II] / [TICS] molecular flux ratios. A hypothetical decomposition pathway of this silane under these conditions is discussed based on the different species formed under electron bombardment of TICS. Transmission electron microscopy investigations demonstrated that the deposited oxide is smooth (roughness sub 2nm) and amorphous. Infrared spectroscopy confirmed the low concentration of hydroxyl groups. The Hydrogen content of the deposited oxide, measured by elastic recoil detection analysis, is as low as 1 at%. 193nm wavelength AIMS investigations of 125nm thick SiO II pads (obtained with [O II] / [TICS] = 325) showed an undetectable light absorption.

Micro-Raman spectroscopy as a tool for the characterization of silicon carbide in power semiconductor material processing

NASA Astrophysics Data System (ADS)

De Biasio, M.; Kraft, M.; Schultz, M.; Goller, B.; Sternig, D.; Esteve, R.; Roesner, M.

2017-05-01

Silicon carbide (SiC) is a wide band-gap semi-conductor material that is used increasingly for high voltage power devices, since it has a higher breakdown field strength and better thermal conductivity than silicon. However, in particular its hardness makes wafer processing difficult and many standard semi-conductor processes have to be specially adapted. We measure the effects of (i) mechanical processing (i.e. grinding of the backside) and (ii) chemical and thermal processing (i.e. doping and annealing), using confocal microscopy to measure the surface roughness of ground wafers and micro-Raman spectroscopy to measure the stresses induced in the wafers by grinding. 4H-SiC wafers with different dopings were studied before and after annealing, using depth-resolved micro-Raman spectroscopy to observe how doping and annealing affect: i.) the damage and stresses induced on the crystalline structure of the samples and ii.) the concentration of free electrical carriers. Our results show that mechanical, chemical and thermal processing techniques have effects on this semiconductor material that can be observed and characterized using confocal microscopy and high resolution micro Raman spectroscopy.

Identification of the Cause of the Stem Neck Fracture in the Hip Joint Endoprosthesis

NASA Astrophysics Data System (ADS)

Ryniewicz, A. M.; Bojko, Ł.; Ryniewicz, A.; Pałka, P.; Ryniewicz, W.

2018-02-01

Endoprosthesis stem fractures are among the rarest complications that occur after hip joint arthroplasty. The aim of this paper is to evaluate the causes of the fractures of the Aura II stem neck, which is an element of an endoprosthesis implanted in a patient. In order to achieve it, a radiogram was evaluated, the FEM analysis was carried out for the hip joint replaced using the Aura II prosthesis and scanning tests as well as a chemical analysis were performed for the focus of fatigue. The tests performed indicate that the most probable causes leading to the fatigue fracture of the Aura II stem under examination were material defects in the process of casting and forging (forging the material with delamination and the presence of brittle oxides and carbides) that resulted in a significant reduction of strength and resistance to corrosion. In the light of an unprecedented stem neck fracture, this information should be an indication for non-destructive tests of ready-made stems aiming to discover the material and technological defects that may arise in the process of casting and drop forging.

Mechanical Mercury Extraction Process® Test Results at Combie Reservoir

NASA Astrophysics Data System (ADS)

Monohan, C.; Alpers, C. N.; Marvin-DiPasquale, M. C.

2016-12-01

More than 4,500,000 kilograms (10,000,000 pounds) of mercury (Hg) were used during hydraulic and hard rock mining during the California Gold Rush era, and it is estimated that 10-30% of liquid Hg was lost to the environment. Mercury is entrained in river gravels containing hydraulic mining debris and is incorporated into the aquatic food chain, causing numerous environmental and public health problems for California communities today. One of the problems is that Hg-contaminated sediment accumulates in water-supply reservoirs such as the Combie Reservoir. Sand miners and irrigation districts have removed these accumulated materials for more than 30 years. The Combie Reservoir Sediment and Mercury Removal Project is to dredge Hg-contaminated sediment from Combie Reservoir while implementing an innovative recovery process to remove the free elemental Hg (Hg(0)) from the dredged material. The project is estimated to take 3 to 5 years to complete and would remove and treat an estimated 100,000 cubic meters (135,000 cubic yards) of sediment from the upstream end of Combie Reservoir. The dredged material will be processed with the Pegasus Mercury Extraction Process® which passes the material through a specialized centrifuge, thereby removing Hg(0) as well as other heavy minerals, including gold (Au) and Au-Hg amalgam. To measure the effectiveness of removal process, multiple equipment tests were conducted in September and October 2009. Total Hg (THg), methylmercury (MeHg) and reactive Hg(II) (operationally defined by reduction of divalent inorganic Hg(II) to Hg(0) with tin(II)) were measured in heads (input material) and tails (output material) from replicate closed system tests. Mass balances were calculated for water, sediment and the above forms of Hg to estimate Hg removal effectiveness in different grain-size fractions. The free Hg(0) in the sand size fraction (> 0.063 mm) that was removed by the Pegasus Mercury Extraction Process® represents approximately 93% of the calculated THg in the head material. Process and equipment design modifications are being pursued to improve Hg recovery from the fine-grained fraction (< 0.063 mm). [Any use of trade, product, or firm names is for descriptive purposes only and does not imply endorsement by the U.S. Government.

Cantilever epitaxial process

DOEpatents

Ashby, Carol I.; Follstaedt, David M.; Mitchell, Christine C.; Han, Jung

2003-07-29

A process of growing a material on a substrate, particularly growing a Group II-VI or Group III-V material, by a vapor-phase growth technique where the growth process eliminates the need for utilization of a mask or removal of the substrate from the reactor at any time during the processing. A nucleation layer is first grown upon which a middle layer is grown to provide surfaces for subsequent lateral cantilever growth. The lateral growth rate is controlled by altering the reactor temperature, pressure, reactant concentrations or reactant flow rates. Semiconductor materials, such as GaN, can be produced with dislocation densities less than 10.sup.7 /cm.sup.2.

Emergent properties resulting from type-II band alignment in semiconductor nanoheterostructures.

PubMed

Lo, Shun S; Mirkovic, Tihana; Chuang, Chi-Hung; Burda, Clemens; Scholes, Gregory D

2011-01-11

The development of elegant synthetic methodologies for the preparation of monocomponent nanocrystalline particles has opened many possibilities for the preparation of heterostructured semiconductor nanostructures. Each of the integrated nanodomains is characterized by its individual physical properties, surface chemistry, and morphology, yet, these multicomponent hybrid particles present ideal systems for the investigation of the synergetic properties that arise from the material combination in a non-additive fashion. Of particular interest are type-II heterostructures, where the relative band alignment of their constituent semiconductor materials promotes a spatial separation of the electron and hole following photoexcitation, a highly desirable property for photovoltaic applications. This article highlights recent progress in both synthetic strategies, which allow for material and architectural modulation of novel nanoheterostructures, as well as the experimental work that provides insight into the photophysical properties of type-II heterostructures. The effects of external factors, such as electric fields, temperature, and solvent are explored in conjunction with exciton and multiexciton dynamics and charge transfer processes typical for type-II semiconductor heterostructures.

Validation of contractor HMA testing data in the materials acceptance process - phase II : final report.

DOT National Transportation Integrated Search

2016-08-01

This study conducted an analysis of the SCDOT HMA specification. A Research Steering Committee provided oversight : of the process. The research process included extensive statistical analyses of test data supplied by SCDOT. : A total of 2,789 AC tes...

World War II Spy Kit: "The Great Nazi Intelligence Coup."

ERIC Educational Resources Information Center

Haight, David

This instructional packet is designed to introduce students to primary source material by having them participate in an historical "what might have been." Students engage in critical thinking and document analysis, and through the process learn about Operation OVERLORD and World War II in general. This spy kit centers on Operation…

40 CFR 63.984 - Fuel gas systems and processes to which storage vessel, transfer rack, or equipment leak...

Code of Federal Regulations, 2010 CFR

2010-07-01

... function in that process; (ii) Transformed by chemical reaction into materials that are not regulated... evaluation (or engineering assessment) that demonstrates the extent to which one or more of the conditions...

40 CFR 63.984 - Fuel gas systems and processes to which storage vessel, transfer rack, or equipment leak...

Code of Federal Regulations, 2011 CFR

2011-07-01

... function in that process; (ii) Transformed by chemical reaction into materials that are not regulated... evaluation (or engineering assessment) that demonstrates the extent to which one or more of the conditions...

DOE Office of Scientific and Technical Information (OSTI.GOV)

Wu, T.; Griffin, A. M.; Gorski, C. A.

Dissimilatory microbial reduction of solid-phase Fe(III)-oxides and Fe(III)-bearing phyllosilicates (Fe(III)-phyllosilicates) is an important process in anoxic soils, sediments, and subsurface materials. Although various studies have documented the relative extent of microbial reduction of single-phase Fe(III)-oxides and Fe(III)-phyllosilicates, detailed information is not available on interaction between these two processes in situations where both phases are available for microbial reduction. The goal of this research was to use the model dissimilatory iron-reducing bacterium (DIRB) Geobacter sulfurreducens to study Fe(III)-oxide vs. Fe(III)-phyllosilicate reduction in a range of subsurface materials and Fe(III)-oxide stripped versions of the materials. Low temperature (12K) Mossbauer spectroscopy was usedmore » to infer changes in the relative abundances of Fe(III)-oxide, Fe(III)-phyllosilicate, and phyllosilicate-associated Fe(II) (Fe(II)-phyllosilicate). A Fe partitioning model was employed to analyze the fate of Fe(II) and assess the potential for abiotic Fe(II)-catalyzed reduction of Fe(III)-phyllosilicates. The results showed that in most cases Fe(III)- oxide utilization dominated (70-100 %) bulk Fe(III) reduction activity, and that electron transfer from oxide-derived Fe(II) played only a minor role (ca. 10-20 %) in Fe partitioning. In addition, the extent of Fe(III)-oxide reduction was positively correlated to surface area-normalized cation exchange capacity and the phyllosilicate-Fe(III)/total Fe(III) ratio, which suggests that the phyllosilicates in the natural sediments promoted Fe(III)-oxide reduction by binding of oxide-derived Fe(II), thereby enhancing Fe(III)-oxide reduction by reducing or delaying the inhibitory effect that Fe(II) accumulation on oxide and DIRB cell surfaces has on Fe(III)-oxide reduction. In general our results suggest that although Fe(III)-oxide reduction is likely to dominate bulk Fe(III) reduction in most subsurface sediments, Fe(II) binding by phyllosilicates is likely to play a key role in controlling the long-term kinetics of Fe(III)-oxide reduction.« less

Computation of Material Demand in the Risk Assessment and Mitigation Framework for Strategic Materials (RAMF-SM) Process

DTIC Science & Technology

2015-08-01

Congress concerning requirements for the National Defense Stockpile (NDS) of strategic and critical non- fuel materials. 1 RAMF-SM, which was...critical non- fuel materials. The NDS was established in the World War II era and has been managed by the Department of Defense (DOD) since 1988. By...Department of the Interior. An alternative algorithm is used for materials with intensive defense demands. v Contents 1 .  Introduction

Pyroprocessing of Oxidized Sodium-Bonded Fast Reactor Fuel -- an Experimental Study of Treatment Options for Degraded EBR-II Fuel

DOE Office of Scientific and Technical Information (OSTI.GOV)

S. D. Herrmann; L. A. Wurth; N. J. Gese

An experimental study was conducted to assess pyrochemical treatment options for degraded EBR-II fuel. As oxidized material, the degraded fuel would need to be converted back to metal to enable electrorefining within an existing electrometallurgical treatment process. A lithium-based electrolytic reduction process was studied to assess the efficacy of converting oxide materials to metal with a particular focus on the impact of zirconium oxide and sodium oxide on this process. Bench-scale electrolytic reduction experiments were performed in LiCl-Li2O at 650 °C with combinations of manganese oxide (used as a surrogate for uranium oxide), zirconium oxide, and sodium oxide. The experimentalmore » study illustrated how zirconium oxide and sodium oxide present different challenges to a lithium-based electrolytic reduction system for conversion of select metal oxides to metal.« less

Enhanced Removal of Lead by Chemically and Biologically Treated Carbonaceous Materials

PubMed Central

Mahmoud, Mohamed E.; Osman, Maher M.; Ahmed, Somia B.; Abdel-Fattah, Tarek M.

2012-01-01

Hybrid sorbents and biosorbents were synthesized via chemical and biological treatment of active carbon by simple and direct redox reaction followed by surface loading of baker's yeast. Surface functionality and morphology of chemically and biologically modified sorbents and biosorbents were studied by Fourier Transform Infrared analysis and scanning electron microscope imaging. Hybrid carbonaceous sorbents and biosorbents were characterized by excellent efficiency and superiority toward lead(II) sorption compared to blank active carbon providing a maximum sorption capacity of lead(II) ion as 500 μmol g−1. Sorption processes of lead(II) by these hybrid materials were investigated under the influence of several controlling parameters such as pH, contact time, mass of sorbent and biosorbent, lead(II) concentration, and foreign ions. Lead(II) sorption mechanisms were found to obey the Langmuir and BET isotherm models. The potential applications of chemically and biologically modified-active carbonaceous materials for removal and extraction of lead from real water matrices were also studied via a double-stage microcolumn technique. The results of this study were found to denote to superior recovery values of lead (95.0–99.0 ± 3.0–5.0%) by various carbonaceous-modified-bakers yeast biosorbents. PMID:22629157

Treatment of model and galvanic waste solutions of copper(II) ions using a lignin/inorganic oxide hybrid as an effective sorbent.

PubMed

Ciesielczyk, Filip; Bartczak, Przemysław; Klapiszewski, Łukasz; Jesionowski, Teofil

2017-04-15

A study was made concerning the removal of copper(II) ions from model and galvanic waste solutions using a new sorption material consisting of lignin in combination with an inorganic oxide system. Specific physicochemical properties of the material resulted from combining the activity of the functional groups present in the structure of lignin with the high surface area of the synthesized oxide system (585m 2 /g). Analysis of the porous structure parameters, particle size and morphology, elemental composition and characteristic functional groups confirmed the effective synthesis of the new type of sorbent. A key element of the study was a series of tests of adsorption of copper(II) ions from model solutions. It was determined how the efficiency of the adsorption process was affected by the process time, mass of sorbent, concentration of adsorbate, pH and temperature. Potential regeneration of adsorbent, which provides the possibility of its reusing and recovering the adsorbed copper, was also analyzed. The sorption capacity of the material was measured (83.98mg/g), and the entire process was described using appropriate kinetic models. The results were applied to the design of a further series of adsorption tests, carried out on solutions of real sewage from a galvanizing plant. Copyright © 2017 Elsevier B.V. All rights reserved.

Novel Fabrication and Simple Hybridization of Exotic Material MEMS

DOE Office of Scientific and Technical Information (OSTI.GOV)

Datskos, P.G.; Rajic, S.

1999-11-13

Work in materials other than silicon for MEMS applications has typically been restricted to metals and metal oxides instead of more ''exotic'' semiconductors. However, group III-V and II-VI semiconductors form a very important and versatile collection of material and electronic parameters available to the MEMS and MOEMS designer. With these materials, not only are the traditional mechanical material variables (thermal conductivity, thermal expansion, Young's modulus, etc.) available, but also chemical constituents can be varied in ternary and quaternary materials. This flexibility can be extremely important for both friction and chemical compatibility issues for MEMS. In addition, the ability to continuallymore » vary the bandgap energy can be particularly useful for many electronics and infrared detection applications. However, there are two major obstacles associated with alternate semiconductor material MEMS. The first issue is the actual fabrication of non-silicon devices and the second impediment is communicating with these novel devices. We will describe an essentially material independent fabrication method that is amenable to most group III-V and II-VI semiconductors. This technique uses a combination of non-traditional direct write precision fabrication processes such as diamond turning, ion milling, laser ablation, etc. This type of deterministic fabrication approach lends itself to an almost trivial assembly process. We will also describe in detail the mechanical, electrical, and optical self-aligning hybridization technique used for these alternate-material MEMS.« less

Removal of Cd (II) from synthetic wastewater by alginate-Ayous wood sawdust (Triplochiton scleroxylon) composite material.

PubMed

Njimou, Jacques Romain; Măicăneanu, Andrada; Indolean, Cerasella; Nanseu-Njiki, Charles Péguy; Ngameni, Emmanuel

2016-01-01

The biosorption characteristics of Cd (II) ions from synthetic wastewater using raw Ayous wood sawdust (Triplochiton scleroxylon), r-AS, immobilized by sodium alginate were investigated with respect to pH, biomass quantity, contact time, initial concentration of heavy metal, temperature and stirring rate. The experimental data fitted well with the Langmuir isotherm, suggesting that monolayer adsorption of the cadmium ions onto alginate-Ayous sawdust composite (a-ASC). The obtained monolayer adsorption capacity of a-ASC for Cd (II) was 6.21 mg/g. From the Dubinin-Radushkevich isotherm model, a 5.39 kJ/mol value for the mean free energy was calculated, indicating that Cd (II) biosorption could include an important physisorption stage. Thermodynamic calculations showed that the Cd (II) biosorption process was feasible, endothermic and spontaneous in nature under examined conditions. The results indicated that a-ASC could be an alternative material replacing more costly adsorbents used for the removal of heavy metals.

Numerical Modeling of Contaminant Transport with Rate-Limited Sorption/Desorption in an Aquifer.

DTIC Science & Technology

1989-12-01

thes -t anil duratiin (f ’ls’atiij s𔃻rrts, andi tos gaint fuirthesr midi , of the physical processes involved Ii tie( transport of foreign materials Ii...foruriila rejireselitatiur i f Iic lc~cls of curitirinarit Ili both regliMs waV In~t.rl \\ th105 rtest rictiori, the miodel omu1 hot siriiilaie pulse

COMPLETE ELEMENT ABUNDANCES OF NINE STARS IN THE r -PROCESS GALAXY RETICULUM II

DOE Office of Scientific and Technical Information (OSTI.GOV)

Ji, Alexander P.; Frebel, Anna; Chiti, Anirudh

We present chemical abundances derived from high-resolution Magellan /Magellan Inamori Kyocera Echelle spectra of the nine brightest known red giant members of the ultra-faint dwarf galaxy Reticulum II (Ret II). These stars span the full metallicity range of Ret II (−3.5 < [Fe/H] < −2). Seven of the nine stars have extremely high levels of r -process material ([Eu/Fe] ∼ 1.7), in contrast to the extremely low neutron-capture element abundances found in every other ultra-faint dwarf galaxy studied to date. The other two stars are the most metal-poor stars in the system ([Fe/H] < −3), and they have neutron-capture elementmore » abundance limits similar to those in other ultra-faint dwarf galaxies. We confirm that the relative abundances of Sr, Y, and Zr in these stars are similar to those found in r -process halo stars, but they are ∼0.5 dex lower than the solar r -process pattern. If the universal r -process pattern extends to those elements, the stars in Ret II display the least contaminated known r -process pattern. The abundances of lighter elements up to the iron peak are otherwise similar to abundances of stars in the halo and in other ultra-faint dwarf galaxies. However, the scatter in abundance ratios is large enough to suggest that inhomogeneous metal mixing is required to explain the chemical evolution of this galaxy. The presence of low amounts of neutron-capture elements in other ultra-faint dwarf galaxies may imply the existence of additional r -process sites besides the source of r -process elements in Ret II. Galaxies like Ret II may be the original birth sites of r -process enhanced stars now found in the halo.« less

43 CFR 45.40 - What are the requirements for prehearing conferences?

Code of Federal Regulations, 2010 CFR

2010-10-01

... and the schedule of remaining steps in the hearing process. (e) Failure to attend. Unless the ALJ... an initial prehearing conference with the parties at the time specified in the docketing notice under... material fact and exclude issues that do not qualify for review as factual, material, and disputed; (ii) To...

Workshop on the Design and Processing of Materials by Biomimicking Held in Seattle, Washington on 2-4 April 1991

DTIC Science & Technology

1991-11-01

These materials feature repeating stem-turn elements composed of 1-strands and amino acids predicted to participate in 1-hairpin formation. The...highly ordered crystalline material. Presently we are studying: (i) the effects of amino acid sequence on 1-turn formation, (ii) the influence of stem...length and amino acid composition on chain folding and materials properties, and (iii) the potential for biological incorporation of unnatural amino

Micromechanical Structures Fabrication

DOE Office of Scientific and Technical Information (OSTI.GOV)

Rajic, S

2001-05-08

Work in materials other than silicon for MEMS applications has typically been restricted to metals and metal oxides instead of more ''exotic'' semiconductors. However, group III-V and II-VI semiconductors form a very important and versatile collection of material and electronic parameters available to the MEMS and MOEMS designer. With these materials, not only are the traditional mechanical material variables (thermal conductivity, thermal expansion, Young's modulus, etc.) available, but also chemical constituents can be varied in ternary and quaternary materials. This flexibility can be extremely important for both friction and chemical compatibility issues for MEMS. In addition, the ability to continuallymore » vary the bandgap energy can be particularly useful for many electronics and infrared detection applications. However, there are two major obstacles associated with alternate semiconductor material MEMS. The first issue is the actual fabrication of non-silicon micro-devices and the second impediment is communicating with these novel devices. We have implemented an essentially material independent fabrication method that is amenable to most group III-V and II-VI semiconductors. This technique uses a combination of non-traditional direct write precision fabrication processes such as diamond turning, ion milling, laser ablation, etc. This type of deterministic fabrication approach lends itself to an almost trivial assembly process. We also implemented a mechanical, electrical, and optical self-aligning hybridization technique for these alternate-material MEMS substrates.« less

Advanced Information Processing. Volume I. Student's Materials. Curriculum Improvement Project. Region II.

ERIC Educational Resources Information Center

Stanford, Linda

This course curriculum is intended for use in an advanced information processing course. It builds on the skills developed in the previous information processing course but goes one step further by requiring students to perform in a simulated office environment and improve their decision-making skills. This volume contains two parts of the…

Acquisitions. ERIC Processing Manual, Section II.

ERIC Educational Resources Information Center

Mathews, Gail, Ed.

Rules and guidelines are provided for the process of acquiring documents and journal articles to be considered for inclusion in the ERIC database. The differing responsibilities of the Government, the ERIC Clearinghouses, and the ERIC Facility are delineated. The various methods by which documentary material can be obtained are described. Sample…

The guayule plant : a renewable, domestic source of binder materials for flexible pavement mixtures.

DOT National Transportation Integrated Search

2013-01-01

The guayule (pronounced 'why-YOU-lee') plant grows in arid and semi-arid regions (e.g. the southwestern U.S.) and is a source of natural rubber. It was cultivated and processed during the World War II rubber shortage and is currently being processed ...

Growth of Bulk Wide Bandgap Semiconductor Crystals and Their Potential Applications

NASA Technical Reports Server (NTRS)

Chen, Kuo-Tong; Shi, Detang; Morgan, S. H.; Collins, W. Eugene; Burger, Arnold

1997-01-01

Developments in bulk crystal growth research for electro-optical devices in the Center for Photonic Materials and Devices since its establishment have been reviewed. Purification processes and single crystal growth systems employing physical vapor transport and Bridgman methods were assembled and used to produce high purity and superior quality wide bandgap materials such as heavy metal halides and II-VI compound semiconductors. Comprehensive material characterization techniques have been employed to reveal the optical, electrical and thermodynamic properties of crystals, and the results were used to establish improved material processing procedures. Postgrowth treatments such as passivation, oxidation, chemical etching and metal contacting during the X-ray and gamma-ray device fabrication process have also been investigated and low noise threshold with improved energy resolution has been achieved.

27 CFR 19.372 - Receipt of spirits, wines and alcoholic flavoring materials for processing.

Code of Federal Regulations, 2010 CFR

2010-04-01

... 27 Alcohol, Tobacco Products and Firearms 1 2010-04-01 2010-04-01 false Receipt of spirits, wines... Spirits, Wines and Alcoholic Flavoring Materials § 19.372 Receipt of spirits, wines and alcoholic...) Wines (i) from the storage account at the same plant, or (ii) by transfer in bond from a bonded wine...

Micarta Propellers II : Method of Construction

NASA Technical Reports Server (NTRS)

Caldwell, F W; Clay, N S

1924-01-01

The methods used in manufacturing Micarta propellers differ considerably from those employed with wood propellers on account of the hardness of the materials. The propellers must be formed accurately to size in a mold and afterwards balanced without the customary trimming of the material from the tips. Described here are the pressing and molding processes, filing, boring, balancing, and curing.

Materials Science Clean Room Facility at Tulane University (Final Technical Report)

DOE Office of Scientific and Technical Information (OSTI.GOV)

Altiero, Nicholas

2010-09-30

The project involves conversion of a 3,000 sq. ft. area into a clean room facility for materials science research. It will be accomplished in phases. Phase I will involve preparation of the existing space, acquisition and installation of clean room equipped with a pulsed laser deposition (PLD) processing system, and conversion of ancillary space to facilitate the interface with the clean room. From a capital perspective, Phases II and III will involve the acquisition of additional processing, fabrication, and characterization equipment and capabilities.

Electrochemical and mechanical polishing and shaping method and system

NASA Technical Reports Server (NTRS)

Engelhaupt, Darell E. (Inventor); Gubarev, Mikhail V. (Inventor); Jones, William David (Inventor); Ramsey, Brian D. (Inventor); Benson, Carl M. (Inventor)

2011-01-01

A method and system are provided for the shaping and polishing of the surface of a material selected from the group consisting of electrically semi-conductive materials and conductive materials. An electrically non-conductive polishing lap incorporates a conductive electrode such that, when the polishing lap is placed on the material's surface, the electrode is placed in spaced-apart juxtaposition with respect to the material's surface. A liquid electrolyte is disposed between the material's surface and the electrode. The electrolyte has an electrochemical stability constant such that cathodic material deposition on the electrode is not supported when a current flows through the electrode, the electrolyte and the material. As the polishing lap and the material surface experience relative movement, current flows through the electrode based on (i) adherence to Faraday's Law, and (ii) a pre-processing profile of the surface and a desired post-processing profile of the surface.

International Collaboration Program in Innovative Chemical Processing of Superior Electronic and Optical Materials

DTIC Science & Technology

1993-06-01

Peyghambarian for X(3) measurements. 3. Research on Nonlinear Optical Materials based on Ultrafine Metal Clusters in ORMOSILS Another family of ultrafine ... particles which, when dispersed in a glassy matrix, has been show to have high X(3) involves metal clusters. Because of the importance of obtaining...NSG Workshop on: Science and Application of Photonic Materials II, Osaka, Japan, November (1992). Haixing, Z., and Mackenzie, J.D., " Ultrafine

Bridging the Gap: Linking Simulation and Testing

DOE Office of Scientific and Technical Information (OSTI.GOV)

Krajewski, Paul E.; Carsley, John; Stoudt, Mark R.

2012-09-01

The Materials Genome Initiative (MGI) which is a key enabler for the Advanced Manufacturing Partnership, announced in 2011 by U.S. President Barack Obama, was established to accelerate the development and deployment of advanced materials. The MGI is driven by the need to "bridge the gap" between (I) experimental results and computational analysis to enable the rapid development and validation of new mateirals, and (II) the processes required to convert these materials into useable goods.

FY-16 Technology Gap Study Technical Report: Analysis of Undissolved Anode Materials of Mark-IV Electrorefiner

DOE Office of Scientific and Technical Information (OSTI.GOV)

Yoo, Tae-Sic; Vaden, DeeEarl; Westphal, Brian Robert

2016-01-01

The Experimental Breeder Reactor II (EBR-II) is a sodium cooled fast reactor developed at Argonne National Laboratory (ANL). The used fuels from the EBR-II are currently being treated in the Fuel Conditioning Facility (FCF) at the Idaho National Laboratory (INL). The Mark IV (Mk-IV) electrorefiner (ER) is a unit process in the FCF, which is primarily assigned to treating the used driver fuels. The stainless steel anode baskets hold the chopped spent driver fuel segments. During electrorefining, the anode baskets are immersed into the electrolyte and the used fuel is dissolved electrochemically. Perforated sides and bottoms allow the flow ofmore » the electrolyte into and out of the anode baskets. The steel cathode is also immersed into the electrolyte and collects the reduced products. The active metal contents in the used fuel (e.g., Cs, Sr, lanthanides, Pu, etc.) reacts with uranium cations in the electrolyte and progressively reports to the electrolyte. Noble metals are mostly retained in the cladding hulls. Varying quantities of zirconium are retained in the cladding hulls depending on the operational conditions of the Mk-IV ER. The undissolved anode materials are removed from the anode baskets and stored for subsequent metal waste form processing. These undissolved materials typically include undissolved fuels, stainless steel cladding, and adhering electrolyte. A couple of hulls are retrieved for chemical analysis and used for estimating the composition of the entire undissolved anode materials. The mass balance attempt based on this practice of estimating the undissolved anode materials has been a challenge due to inherently high sampling errors associated with heterogeneous undissolved material compositions. Responding to the prescribed challenge, this report investigates chemical analysis data as a whole and finds noticeable trends in the compositions of undissolved anode material samples with respect to the mass of the whole undissolved anode materials. Based upon this discovery, an empirical model is proposed.« less

Use of DSC and DMA Techniques to Help Investigate a Material Anomaly for PTFE Used in Processing a Piston Cup for the Urine Processor Assembly (UPA) on International Space Station (ISS)

NASA Technical Reports Server (NTRS)

Wingard, Doug

2010-01-01

Human urine and flush water are eventually converted into drinking water with the Urine Processor Assembly (UPA) aboard the International Space Station (ISS). This conversion is made possible through the Distillation Assembly (DA) of the UPA. One component of the DA is a molded circular piston cup made of virgin polytetrafluoroethylene (PTFE). The piston cup is assembled to a titanium component using eight fasteners and washers. Molded PTFE produced for spare piston cups in the first quarter of 2010 was different in appearance and texture, and softer than material molded for previous cups. For the suspect newer PTFE material, cup fasteners were tightened to only one-half the required torque value, yet the washers embedded almost halfway into the material. The molded PTFE used in the DA piston cup should be Type II, based on AMS 3667D and ASTM D4894 specifications. The properties of molded PTFE are considerably different between Type I and II materials. Engineers working with the DA thought that if Type I PTFE was molded by mistake instead of Type II material, that could have resulted in the anomalous material properties. Typically, the vendor molds flat sheet PTFE from the same material lot used to mold the piston cups, and tensile testing as part of quality control should verify that the PTFE is Type II material. However, for this discrepant lot of material, such tensile data was not available. Differential scanning calorimetry (DSC) and dynamic mechanical analysis (DMA) were two of the testing techniques used at the NASA/Marshall Space Flight Center (MSFC) to investigate the anomaly for the PTFE material. Other techniques used on PTFE specimens were: Shore D hardness testing, tensile testing on dog bone specimens and a qualitative estimation of porosity by optical and scanning electron microscopy.

Advanced bulk processing of lightweight materials for utilization in the transportation sector

NASA Astrophysics Data System (ADS)

Milner, Justin L.

The overall objective of this research is to develop the microstructure of metallic lightweight materials via multiple advanced processing techniques with potentials for industrial utilization on a large scale to meet the demands of the aerospace and automotive sectors. This work focused on (i) refining the grain structure to increase the strength, (ii) controlling the texture to increase formability and (iii) directly reducing processing/production cost of lightweight material components. Advanced processing is conducted on a bulk scale by several severe plastic deformation techniques including: accumulative roll bonding, isolated shear rolling and friction stir processing to achieve the multiple targets of this research. Development and validation of the processing techniques is achieved through wide-ranging experiments along with detailed mechanical and microstructural examination of the processed material. On a broad level, this research will make advancements in processing of bulk lightweight materials facilitating industrial-scale implementation. Where accumulative roll bonding and isolated shear rolling, currently feasible on an industrial scale, processes bulk sheet materials capable of replacing more expensive grades of alloys and enabling low-temperature and high-strain-rate formability. Furthermore, friction stir processing to manufacture lightweight tubes, made from magnesium alloys, has the potential to increase the utilization of these materials in the automotive and aerospace sectors for high strength - high formability applications. With the increased utilization of these advanced processing techniques will significantly reduce the cost associated with lightweight materials for many applications in the transportation sectors.

Long-Term Effects of Soldering By-Products on Nickel-Coated Copper Wire

NASA Technical Reports Server (NTRS)

Rolin, T. D.; Hodge, R. E.

2008-01-01

An analysis of thirty-year-old, down graded flight cables was conducted to determine the makeup of a green material on the surface of the shielded wire near soldered areas and to ascertain if the green material had corroded the nickel-coated copper wire. Two likely candidates were possible due to the handling and environments to which these cables were exposed. The flux used to solder the cables is known to contain abietic acid, a carboxylic acid found in many pine rosins used for the soldering process. The resulting material copper abietate is green in color and is formed during the application of heat during soldering operations. Copper (II) chloride, which is also green in color is known to contaminate flight parts and is corrosive. Data is presented that shows the material is copper abietate, not copper (II) chloride, and more importantly that the abietate does not aggressively attack nickel-plated copper wire.

A Bookless Library, Part II: Managing Access Services with No In-House Collections

ERIC Educational Resources Information Center

Sewell, Bethany B.

2013-01-01

In the spring of 2011, the Penrose Library at the University of Denver began the process of storing all materials, services, and staff to temporary locations in preparation for a building renovation project. The library was faced with the challenge of delivering all materials from an off-site storage facility within two hours of request. A new…

Composition, apparatus, and process, for sorption of gaseous compounds of group II-VII elements

DOEpatents

Tom, Glenn M.; McManus, James V.; Luxon, Bruce A.

1991-08-06

Scavenger compositions are disclosed, which have utility for effecting the sorptive removal of hazardous gases containing Group II-VII elements of the Periodic Table, such as are widely encountered in the manufacture of semiconducting materials and semiconductor devices. Gas sorption processes including the contacting of Group II-VII gaseous compounds with such scavenger compositions are likewise disclosed, together with critical space velocity contacting conditions pertaining thereto. Further described are gas contacting apparatus, including mesh structures which may be deployed in gas contacting vessels containing such scavenger compositions, to prevent solids from being introduced to or discharged from the contacting vessel in the gas stream undergoing treatment. A reticulate heat transfer structure also is disclosed, for dampening localized exothermic reaction fronts when gas mixtures comprising Group II-VII constituents are contacted with the scavenger compositions in bulk sorption contacting vessels according to the invention.

Adsorption of Azo-Dye Orange II from Aqueous Solutions Using a Metal-Organic Framework Material: Iron- Benzenetricarboxylate

PubMed Central

Rojas García, Elizabeth; López Medina, Ricardo; May Lozano, Marcos; Hernández Pérez, Isaías; Valero, Maria J.; Maubert Franco, Ana M.

2014-01-01

A Metal-Organic Framework (MOF), iron-benzenetricarboxylate (Fe(BTC)), has been studied for the adsorptive removal of azo-dye Orange II from aqueous solutions, where the effect of various parameters was tested and isotherm and kinetic models were suggested. The adsorption capacities of Fe(BTC) were much higher than those of an activated carbon. The experimental data can be best described by the Langmuir isotherm model (R2 > 0.997) and revealed the ability of Fe(BTC) to adsorb 435 mg of Orange II per gram of adsorbent at the optimal conditions. The kinetics of Orange II adsorption followed a pseudo-second-order kinetic model, indicating the coexistence of physisorption and chemisorption, with intra-particle diffusion being the rate controlling step. The thermodynamic study revealed that the adsorption of Orange II was feasible, spontaneous and exothermic process (−25.53 kJ·mol−1). The high recovery of the dye showed that Fe(BTC) can be employed as an effective and reusable adsorbent for the removal of Orange II from aqueous solutions and showed the economic interest of this adsorbent material for environmental purposes. PMID:28788289

Efficiency of a cleanup technology to remove mercury from natural waters by means of rice husk biowaste: ecotoxicological and chemical approach.

PubMed

Rocha, Luciana S; Lopes, I; Lopes, Cláudia B; Henriques, Bruno; Soares, Amadeu M V M; Duarte, Armando C; Pereira, Eduarda

2014-01-01

In the present work, the efficiency of rice husk to remove Hg(II) from river waters spiked with realistic environmental concentrations of this metal (μg L(-1) range) was evaluated. The residual levels of Hg(II) obtained after the remediation process were compared with the guideline values for effluents discharges and water for human consumption, and the ecotoxicological effects using organisms of different trophic levels were assessed. The rice husk sorbent proved to be useful in decreasing Hg(II) contamination in river waters, by reducing the levels of Hg(II) to values of ca. 8.0 and 34 μg L(-1), for an Hg(II) initial concentration of 50 and 500 μg L(-1), respectively. The remediation process with rice husk biowaste was extremely efficient in river waters spiked with lower levels of Hg(II), being able to eliminate the toxicity to the exposed organisms algae Pseudokirchneriella subcapitata and rotifer Brachionus calyciflorus and ensure the total survival of Daphnia magna species. For concentrations of Hg(II) tenfold higher (500 μg L(-1)), the remediation process was not adequate in the detoxification process, still, the rice husk material was able to reduce considerably the toxicity to the bacteria Vibrio fischeri, algae P. subcapitata and rotifer B. calyciflorus, whose responses where fully inhibited during its exposure to the non-remediated river water. The use of a battery of bioassays with organisms from different trophic levels and whose sensitivity revealed to be different and dependent on the levels of Hg(II) contamination proved to be much more accurate in predicting the ecotoxicological hazard assessment of the detoxification process by means of rice husk biowaste.

Comparative transition performance of several nosetip materials as defined by ballistics-range testing

DOE Office of Scientific and Technical Information (OSTI.GOV)

Reda, D.C.

1979-01-01

Requirements and techniques for conducting aerothermodynamic tests of reentry body nosetips/materials in hypersonic ballistics-range environments (ISA 22nd IIS), and associated data interpretation/analyses methods using interactive graphics (ISA 24th IIS) have been outlined. Such testing, which centers on the utilization of electro-optical pyrometry for the measurement of nosetip surface temperature distributions, has provided both the aerothermodynamics and materials-development communities with valuable new capabilities. From an aerothermodynamics standpoint, experimental results serve to test the validity of existing computer codes/correlations, as well as to expand the data base necessary for the generation of improved predictive techniques. From a materials-development standpoint, results serve tomore » define relationships between fabrication/processing methods and associated material thermal response as well as to provide for relative ranking of candidate materials under controlled reentry conditions. Following these multipurpose objectives, ballistic-range tests of preablated graphite and carbon/carbon composite nosetips have been conducted. Results are presented herein which illustrate the comparative transition performance of five nosetip materials from both mean and statistical (degree-of-asymmetry) viewpoints.« less

An analysis of variability in the manufacturing of dexosomes: implications for development of an autologous therapy.

PubMed

Patel, Sanjay; Mehta-Damani, Anita; Shu, Helen; Le Pecq, Jean-Bernard

2005-10-20

Dexosomes are nanometer-size vesicles released by dendritic-cells, possessing much of the cellular machinery required to stimulate an immune response (i.e. MHC Class I and II). The ability of patient-derived dexosomes loaded with tumor antigens to elicit anti-tumor activity is currently being evaluated in clinical trials. Unlike conventional biologics, where variability between lots of product arises mostly from the manufacturing process, an autologous product has inherent variability in the starting material due to heterogeneity in the human population. In an effort to assess the variability arising from the dexosome manufacturing process versus the human starting material, 144 dexosome preparations from normal donors (111) and cancer patients (33) from two Phase I clinical trials were analyzed. A large variability in the quantity of dexosomes (measured as the number of MHC Class II molecules) produced between individual lots was observed ( > 50-fold). An analysis of intra-lot variability shows that the manufacturing process introduces relatively little of this variability. To identify the source(s) of variability arising from the human starting material, distributions of the key parameters involved in dexosome production were established, and a model created. Computer simulations using this model were performed, and compared to the actual data observed. The main conclusion from these simulations is that the number of cells collected per individual and the productivity of these cells of are the principal sources of variability in the production of Class II. The approach described here can be extended to other autologous therapies in general to evaluate control of manufacturing processes. Moreover, this analysis of process variability is directly applicable to production at a commercial scale, since the large scale manufacture of autologous products entails an exact process replication rather than scale-up in volume, as is the case with traditional drugs or biologics. Copyright 2005 Wiley Periodicals, Inc.

[Preparation of polyacrylonitrile/natural sand composite materials and analysis of adsorption properties of Pb(II) on it by FAAS].

PubMed

Abduwayit, Medine; Nurulla, Ismayil; Abliz, Shawket

2015-02-01

Surfaces of natural sand particles were modified with (3-chloropropyl) trichlorosilane, so that bridging groups were introduced on the surfaces of natural sand particles; By grafting polyacrylonitrile onto the modified surfaces of the natural sand particles, a novelpolyacrylonitrile/natural sand composite material was prepared from the acrylonitrile, the azobisisobutyronitrile, the divinylbenzene and the modified natural sand particles, which are as functional monomer, initiator, either skeleton monomer or cross-linking agent and carrier respectively; the composite materials were characterized by using infrared spectroscopy and scanning electron microscopy; On the FTIR spectrum, the main characteristic peaks of various functional groups including nitrile, benzene ring, and silicon hydroxyl, which were from functional monomer, cross-linking agent and carrier respectively, were observed. On the SEM, two different cross section morphologies having different density which were from acrylonitrile and modified sand particles were observed; This proved that the polyacrylonitrile was decorated on modified sand particles during our preparation process. After preparing the composite materials, micro-column of separation and preconcentration was prepared using the composite materials as filler; the adsorption of some toxic heavy metal ions onto the composite materials was observed by flame atomic absorption spectrometry (FAAS); The results show that the adsorption of Pb2+ onto the composite materials was more stronger than the absorption of other toxic heavy metal ions, therefore, in this paper, the adsorption of Pb2+ onto the composite materials was mainly studied, at room temperature, when pH and flow rate of solution were 5. 4 and 4 mL x min(-1) respectively, the trace Pb(II) ions could be quantitatively adsorbed onto the composite materials; the maximum adsorption capacity of Pb(II) on the composite materials can reach 62.9 mg x g(-1). The column was eluted by 0.5 mol x L(-1) HCl and recovery of Pb(II) was more than 96%.

30 CFR 250.912 - What plans must I submit under the Platform Verification Program?

Code of Federal Regulations, 2010 CFR

2010-07-01

... computer programs used in the design process; and (3) A summary of the major design considerations and the...) Structural tolerances; (ii) Welding procedures; (iii) Material (concrete, gravel, or silt) placement methods...

DOE Office of Scientific and Technical Information (OSTI.GOV)

Bramante, Joseph; Linden, Tim

Recent observations of Reticulum II have uncovered an overabundance of r -process elements compared to similar ultra-faint dwarf spheroidal galaxies (UFDs). Because the metallicity and star formation history of Reticulum II appear consistent with all known UFDs, the high r -process abundance of Reticulum II suggests enrichment through a single, rare event, such as a double neutron star (NS) merger. However, we note that this scenario is extremely unlikely, as binary stellar evolution models require significant supernova natal kicks to produce NS–NS or NS–black hole (BH) mergers, and these kicks would efficiently remove compact binary systems from the weak gravitationalmore » potentials of UFDs. We examine alternative mechanisms for the production of r -process elements in UFDs, including a novel mechanism wherein NSs in regions of high dark matter (DM) density implode after accumulating a BH-forming mass of DM. We find that r -process proto-material ejection by tidal forces, when a single NS implodes into a BH, can occur at a rate matching the r -process abundance of both Reticulum II and the Milky Way. Remarkably, DM models which collapse a single NS in observed UFDs also solve the missing pulsar problem in the Milky Way Galactic Center. We propose tests specific to DM r -process production which may uncover or rule out this model.« less

Development of a Mini-Freeze Dryer for Material-Sparing Laboratory Processing with Representative Product Temperature History.

PubMed

Obeidat, Wasfy M; Sahni, Ekneet; Kessler, William; Pikal, Michael

2018-02-01

The goal of the work described in this publication was to evaluate a new, small, material-sparing freeze dryer, denoted as the "mini-freeze dryer or mini-FD", capable of reproducing the product temperature history of larger freeze dryers, thereby facilitating scale-up. The mini-FD wall temperatures can be controlled to mimic loading procedures and dryer process characteristics of larger dryers. The mini-FD is equipped with a tunable diode laser absorption spectroscopy (TDLAS) water vapor mass flow monitor and with other advanced process analytical technology (PAT) sensors. Drying experiments were performed to demonstrate scalability to larger freeze dryers, including the determination of vial heat transfer coefficients, K v . Product temperature histories during K v runs were evaluated and compared with those obtained with a commercial laboratory-scale freeze dryer (LyoStar II) for sucrose and mannitol product formulations. When the mini-FD wall temperature was set at the LyoStar II band temperature (- 20°C) to mimic lab dryer edge vials, edge vial drying in the mini-FD possessed an average K v within 5% of those obtained during drying in the LyoStar II. When the wall temperature of the mini-FD was set equal to the central vial product temperature, edge vials behaved as center vials, possessing a K v value within 5% of those measured in the LyoStar II. During both K v runs and complete product freeze drying runs, the temperature-time profiles for the average edge vials and central vial in the mini-FD agreed well with the average edge and average central vials of the LyoStar II.

Dynamic free energy surfaces for sodium diffusion in type II silicon clathrates.

PubMed

Slingsby, J G; Rorrer, N A; Krishna, L; Toberer, E S; Koh, C A; Maupin, C M

2016-02-21

Earth abundant semiconducting type II Si clathrates have attracted attention as photovoltaic materials due to their wide band gaps. To realize the semiconducting properties of these materials, guest species that arise during the synthesis process must be completely evacuated from the host cage structure post synthesis. A common guest species utilized in the synthesis of Si clathrates is Na (metal), which templates the clathrate cage formation. Previous experimental investigations have identified that it is possible to evacuate Na from type II clathrates to an occupancy of less than 1 Na per unit cell. This work investigates the energetics, kinetics, and resulting mechanism of Na diffusion through type II Si clathrates by means of biased molecular dynamics and kinetic Monte Carlo simulations. Well-tempered metadynamics has been used to determine the potential of mean force for Na moving between clathrate cages, from which the thermodynamic preferences and transition barrier heights have been obtained. Kinetic Monte Carlo simulations based on the metadynamics results have identified the mechanism of Na diffusion in type II Si clathrates. The overall mechanism consists of a coupled diffusive process linked via electrostatic guest-guest interactions. The large occupied hexakaidechedral cages initially empty their Na guests to adjacent empty large cages, thereby changing the local electrostatic environment around the occupied small pentagonal dodecahedral cages and increasing the probability of Na guests to leave the small cages. This coupled process continues through the cross-over point that is identified as the point where large and small cages are equally occupied by Na guests. Further Na removal results in the majority of guests residing in the large cages as opposed to the small cages, in agreement with experiments, and ultimately a Na free structure.

Kinetic characteristics of Cu (II) adsorption on nano(poly)-cumulene

NASA Astrophysics Data System (ADS)

Babkin, Alexander; Neskoromnaya, Elena; Burakova, Irina; Kucherova, Ananstasia; Burakov, Alexander; Mkrtchyan, Elina

2017-11-01

The present paper considers the possibility of using a new type of nanocarbon materials for sorption - polycumulene modified with "Taunit-M" carbon nanotubes or graphene nanoplatelets. To evaluate the efficiency of these novel nanomodified materials as sorbents, the following studies were carried out: 1) determination of the optimum pH value to perform static batch sorption experiments, 2) identification of the onset of equilibrium for the adsorption of heavy metal ions (on the example of Cu(II) ions), and 3) elucidation of kinetic adsorption mechanisms. As a result of implementation of kinetic models such as external and internal diffusion, as well as pseudo-first- and pseudo-second-order and Elovich (to determine the contribution of chemisorption), rate constants for the Cu(II) adsorption were estimated. It was noted that the absorption process occurs in a mixed-diffusion mode with the influence of the limiting factor - "sorbate-sorbate" chemical interaction. The equilibrium time was found to be 45 min at the sorption capacity values of about 30.71 mg g-1 (in the case of the material containing carbon nanotubes) and about 24.7 mg g-1 (in the case of the material containing graphene nanoplatelets).

Overview of SBIR Phase II Work on Hollow Graphite Fibers

NASA Technical Reports Server (NTRS)

Stallcup, Michael; Brantley, Lott W. (Technical Monitor)

2001-01-01

Ultra-Lightweight materials are enabling for producing space based optical components and support structures. Heretofore, innovative designs using existing materials has been the approach to produce lighter-weight optical systems. Graphite fiber reinforced composites, because of their light weight, have been a material of frequent choice to produce space based optical components. Hollow graphite fibers would be lighter than standard solid graphite fibers and, thus, would save weight in optical components. The Phase I SBIR program demonstrated it is possible to produce hollow carbon fibers that have strengths up to 4.2 GPa which are equivalent to commercial fibers, and composites made from the hollow fibers had substantially equivalent composite strengths as commercial fiber composites at a 46% weight savings. The Phase II SBIR program will optimize processing and properties of the hollow carbon fiber and scale-up processing to produce sufficient fiber for fabricating a large ultra-lightweight mirror for delivery to NASA. Information presented here includes an overview of the strength of some preliminary hollow fibers, photographs of those fibers, and a short discussion of future plans.

Proceedings of a Workshop on Polar Stratospheric Clouds: Their Role in Atmospheric Processes

NASA Technical Reports Server (NTRS)

Hamill, P. (Editor); Mcmaster, L. R. (Editor)

1984-01-01

The potential role of polar stratospheric clouds in atmospheric processes was assessed. The observations of polar stratospheric clouds with the Nimbus 7 SAM II satellite experiment were reviewed and a preliminary analysis of their formation, impact on other remote sensing experiments, and potential impact on climate were presented. The potential effect of polar stratospheric clouds on climate, radiation balance, atmospheric dynamics, stratospheric chemistry and water vapor budget, and cloud microphysics was assessed. Conclusions and recommendations, a synopsis of materials and complementary material to support those conclusions and recommendations are presented.

Spectroscopic characterization of iron-doped II-VI compounds for laser applications

NASA Astrophysics Data System (ADS)

Martinez, Alan

The middle Infrared (mid-IR) region of the electromagnetic spectrum between 2 and 15 ?m has many features which are of interest to a variety of fields such as molecular spectroscopy, biomedical applications, industrial process control, oil prospecting, free-space communication and defense-related applications. Because of this, there is a demand for broadly tunable, laser sources operating over this spectral region which can be easily and inexpensively produced. II-VI semiconductor materials doped with transition metals (TM) such as Co 2+, Cr2+, or Fe2+ exhibit highly favorable spectroscopic characteristics for mid-IR laser applications. Among these TM dopants, Fe2+ has absorption and emission which extend the farthest into the longer wavelength portion of the mid-IR. Fe2+:II-VI crystals have been utilized as gain elements in laser systems broadly tunable over the 3-5.5 microm range [1] and as saturable absorbers to Q -switch [2] and mode-lock [3] laser cavities operating over the 2.7-3 microm. TM:II-VI laser gain elements can be fabricated inexpensively by means of post-growth thermal diffusion with large homogeneous dopant concentration and good optical quality[4,5]. The work outlined in this dissertation will focus on the spectroscopic characterization of TM-doped II-VI semiconductors. This work can be categorized into three major thrusts: 1) the development of novel laser materials, 2) improving and extending applications of TM:II-VI crystals as saturable absorbers, and 3) fabrication of laser active bulk crystals. Because current laser sources based on TM:II-VI materials do not cover the entire mid-IR spectral region, it is necessary to explore novel laser sources to extend available emissions toward longer wavelengths. The first objective of this dissertation is the spectroscopic characterization of novel ternary host crystals doped with Fe2+ ions. Using crystal field engineering, laser materials can be prepared with emissions placed in spectral regions not currently covered by available sources while maintaining absorption which overlaps with available pump sources. Because optimization of these materials requires extensive experimentation, a technique to fabricate and characterize novel crystals in powder form was developed, eliminating the need for the crystal growth. Powders were characterized using Raman, photoluminescence studies, and kinetics of luminescence. The first demonstration of random lasing of Fe:ZnCdTe powder at 6 microm was reported. These results show promise for the development of these TM-doped ternary II-VI compounds as laser gain media operating at 6 microm and longer. The second major objective was to study the performance of TM:II-VI elements as saturable absorber Q-switches and mode-lockers in flash lamp pumped Er:YAG and Er:Cr:YSGG cavities. Different cavity schemes were arranged to eliminate depolarization losses and improve Q-switching performance in Er:YAG and the first use of Cr:ZnSe to passively Q -switch an Er:Cr:YSGG cavity was demonstrated. While post-growth thermal diffusion is an effective way to prepare large-scale highly doped TM:II-VI laser elements, the diffusion rate of some ions into II-VI semiconductors is too low to make this method practical for large crystals. The third objective was to improve the rate of thermal diffusion of iron into II-VI semiconductor crystals by means of gamma-irradiation during the diffusion process. When exposed to a dose rate of 44 R/s during the diffusion process, the diffusion coefficient for Fe into ZnSe showed improvement of 60% and the diffusion coefficient of Fe into ZnS showed improvement of 30%.

PATRAM '80. Proceedings. Volume 1

DOE Office of Scientific and Technical Information (OSTI.GOV)

Huebner, H.W.

Volume 1 contains papers from the following sessions: Plenary Session; Regulations, Licensing and Standards; LMFBR Systems Concepts; Risk/Safety Assessment I; Systems and Package Design; US Institutional Issues; Risk/Safety Assessment II; Leakage, Leak Rate and Seals; Poster Session A; Operations and Systems Experience I; Manufacturing Processes and Materials; and Quality Assurance and Maintenance. Individual papers were processed. (LM)

Service Delivery to the Handicapped: The Role of the Federal Procurement Process. Part II. Selecting Contractors by Competitive Award.

ERIC Educational Resources Information Center

Donaldosn, William S.; Stephens, Thomas M.

1979-01-01

Sections address the RFP/IFB (Request for Proposals/Invitation for Bids) process and procedures for selecting the "best" contract. In reviewing the federal procurement code, and the recent decision of the Government Accounting Office, particularly regarding the NIMIS (National Instructional Materials Information System contract), inconsistencies…

Military Curricula for Vocational & Technical Education. Metals Processing Specialist, Blocks I and II, Classroom Course 13-5.

ERIC Educational Resources Information Center

Ohio State Univ., Columbus. National Center for Research in Vocational Education.

These curriculum materials are the first section of a four-part, secondary-postsecondary-level course in metals processing. The course is one of a number of military-developed curriculum packages selected for adaptation to vocational instruction and curriculum development in a civilian setting. Block I, Introduction to Oxyacetylene Welding,…

Distance Learning for Teacher Education. Report of a Technical Working Group Meeting (Islamabad, Pakistan, 4-16 November 1981). Volume II: Guidelines on Development of Materials.

ERIC Educational Resources Information Center

United Nations Educational, Scientific, and Cultural Organization, Bangkok (Thailand). Regional Office for Education in Asia and the Pacific.

This handbook, the second volume in a series of three publications on distance education, presents guidelines on structures and strategies in organizations and the processes of materials development. A checklist of specific items is included for each topic addressed. The first guidelines are addressed to policymakers and senior administrators and…

Study of the Effect of Swelling on Irradiation Assisted Stress Corrosion Cracking

DOE Office of Scientific and Technical Information (OSTI.GOV)

Teysseyre, Sebastien Paul

2016-09-01

This report describes the methodology used to study the effect of swelling on the crack growth rate of an irradiation-assisted stress corrosion crack that is propagating in highly irradiated stainless steel 304 material irradiated to 33 dpa in the Experimental Breeder Reactor-II. The material selection, specimens design, experimental apparatus and processes are described. The results of the current test are presented.

Innovation processes in technologies for the processing of refractory mineral raw materials

NASA Astrophysics Data System (ADS)

Chanturiya, V. A.

2008-12-01

Analysis of the grade of mineral resources of Russia and other countries shows that end products that are competitive in terms of both technological and environmental criteria in the world market can only be obtained by the development and implementation of progressive technologies based on the up-to-date achievements of fundamental sciences. The essence of modern innovation processes in technologies developed in Russia for the complex and comprehensive processing of refractory raw materials with a complex composition is ascertained. These processes include (i) radiometric methods of concentration of valuable components, (ii) high-energy methods of disintegration of highly dispersed mineral components, and (iii) electrochemical methods of water conditioning to obtain target products for solving specific technological problems.

Research & Development of Materials/Processing Methods for Continuous Fiber Ceramic Composites (CFCC) Phase 2 Final Report.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Szweda, A.

2001-01-01

The Department of Energy's Continuous Fiber Ceramic Composites (CFCC) Initiative that begun in 1992 has led the way for Industry, Academia, and Government to carry out a 10 year R&D plan to develop CFCCs for these industrial applications. In Phase II of this program, Dow Corning has led a team of OEM's, composite fabricators, and Government Laboratories to develop polymer derived CFCC materials and processes for selected industrial applications. During this phase, Dow Corning carried extensive process development and representative component demonstration activities on gas turbine components, chemical pump components and heat treatment furnace components.

Strawman II. Recommendations for a regulatory program for mining waste and materials under Subtitle D of the Resource Conservation and Recovery Act. Final report

DOE Office of Scientific and Technical Information (OSTI.GOV)

Not Available

1990-05-21

The package, referred to as 'Strawman II', is a working document that represents EPA's latest staff position on an effective program to regulate wastes and other materials uniquely associated with noncoal mining. Strawman II does not represent a proposed rule. The package consists of two parts: (1) the Foreward, which describes the pre-rulemaking Strawman process, a background and overview of the mining waste program as envisioned in the package, and discussions of major issues concerning the program and its scope; and (2) the Regulatory Approach, presented as '40 CFR XXX, XXY, and XXZ' to reflect how the program might appearmore » in regulatory language. Discussions and amplifications of specific points are also interspersed throughout the Regulatory Approach. EPA encourages all interested parties to convey their views on any and all aspects of the program concept.« less

Biosorption of Pb(II) from aqueous solution by Solanum melongena leaf powder as a low-cost biosorbent prepared from agricultural waste.

PubMed

Yuvaraja, Gutha; Krishnaiah, Nettem; Subbaiah, Munagapati Venkata; Krishnaiah, Abburi

2014-02-01

Solanum melongena leaves are relatively galore and used as inexpensive material. This paper presents the characterization and evaluation of potential of S. melongena leaf powder (SMLP) for removal of Pb(II) from aqueous solution as a function of pH, biomass dosage, initial metal ion concentration, contact time and temperature. Experimental data were analyzed in terms of three kinetic models such as the pseudo-first-order, pseudo-second-order and intraparticle diffusion models and the results showed that the biosorption processes of Pb(II) followed well pseudo-second-order kinetics. Langmuir and Freundlich isotherm models were applied to describe the biosorption process. Langmuir isotherm described the equilibrium data very well, with a maximum monolayer sorption capacity of 71.42 mg/g for Pb(II) ions at 323 K. The biosorption process was spontaneous and endothermic in nature with negative ΔG° (-8.746, -8.509 and -7.983 kJ/mol) and positive value for ΔH° (3.698 kJ/mol). Copyright © 2013 Elsevier B.V. All rights reserved.

Comparison of measured and calculated composition of irradiated EBR-II blanket assemblies.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Grimm, K. N.

1998-07-13

In anticipation of processing irradiated EBR-II depleted uranium blanket subassemblies in the Fuel Conditioning Facility (FCF) at ANL-West, it has been possible to obtain a limited set of destructive chemical analyses of samples from a single EBR-II blanket subassembly. Comparison of calculated values with these measurements is being used to validate a depletion methodology based on a limited number of generic models of EBR-II to simulate the irradiation history of these subassemblies. Initial comparisons indicate these methods are adequate to meet the operations and material control and accountancy (MC and A) requirements for the FCF, but also indicate several shortcomingsmore » which may be corrected or improved.« less

FISPACT-II: An Advanced Simulation System for Activation, Transmutation and Material Modelling

NASA Astrophysics Data System (ADS)

Sublet, J.-Ch.; Eastwood, J. W.; Morgan, J. G.; Gilbert, M. R.; Fleming, M.; Arter, W.

2017-01-01

Fispact-II is a code system and library database for modelling activation-transmutation processes, depletion-burn-up, time dependent inventory and radiation damage source terms caused by nuclear reactions and decays. The Fispact-II code, written in object-style Fortran, follows the evolution of material irradiated by neutrons, alphas, gammas, protons, or deuterons, and provides a wide range of derived radiological output quantities to satisfy most needs for nuclear applications. It can be used with any ENDF-compliant group library data for nuclear reactions, particle-induced and spontaneous fission yields, and radioactive decay (including but not limited to TENDL-2015, ENDF/B-VII.1, JEFF-3.2, JENDL-4.0u, CENDL-3.1 processed into fine-group-structure files, GEFY-5.2 and UKDD-16), as well as resolved and unresolved resonance range probability tables for self-shielding corrections and updated radiological hazard indices. The code has many novel features including: extension of the energy range up to 1 GeV; additional neutron physics including self-shielding effects, temperature dependence, thin and thick target yields; pathway analysis; and sensitivity and uncertainty quantification and propagation using full covariance data. The latest ENDF libraries such as TENDL encompass thousands of target isotopes. Nuclear data libraries for Fispact-II are prepared from these using processing codes PREPRO, NJOY and CALENDF. These data include resonance parameters, cross sections with covariances, probability tables in the resonance ranges, PKA spectra, kerma, dpa, gas and radionuclide production and energy-dependent fission yields, supplemented with all 27 decay types. All such data for the five most important incident particles are provided in evaluated data tables. The Fispact-II simulation software is described in detail in this paper, together with the nuclear data libraries. The Fispact-II system also includes several utility programs for code-use optimisation, visualisation and production of secondary radiological quantities. Included in the paper are summaries of results from the suite of verification and validation reports available with the code.

Green Adsorbents for Wastewaters: A Critical Review

PubMed Central

Kyzas, George Z.; Kostoglou, Margaritis

2014-01-01

One of the most serious environmental problems is the existence of hazardous and toxic pollutants in industrial wastewaters. The major hindrance is the simultaneous existence of many/different types of pollutants as (i) dyes; (ii) heavy metals; (iii) phenols; (iv) pesticides and (v) pharmaceuticals. Adsorption is considered to be one of the most promising techniques for wastewater treatment over the last decades. The economic crisis of the 2000s led researchers to turn their interest in adsorbent materials with lower cost. In this review article, a new term will be introduced, which is called “green adsorption”. Under this term, it is meant the low-cost materials originated from: (i) agricultural sources and by-products (fruits, vegetables, foods); (ii) agricultural residues and wastes; (iii) low-cost sources from which most complex adsorbents will be produced (i.e., activated carbons after pyrolysis of agricultural sources). These “green adsorbents” are expected to be inferior (regarding their adsorption capacity) to the super-adsorbents of previous literature (complex materials as modified chitosans, activated carbons, structurally-complex inorganic composite materials etc.), but their cost-potential makes them competitive. This review is a critical approach to green adsorption, discussing many different (maybe in some occasions doubtful) topics such as: (i) adsorption capacity; (ii) kinetic modeling (given the ultimate target to scale up the batch experimental data to fixed-bed column calculations for designing/optimizing commercial processes) and (iii) critical techno-economical data of green adsorption processes in order to scale-up experiments (from lab to industry) with economic analysis and perspectives of the use of green adsorbents. PMID:28788460

It Systems Supporting the Management of Production Capacity

NASA Astrophysics Data System (ADS)

Milewska, Elżbieta

2017-03-01

The paper presents the problem of manufacturing process flexibility in view of a company's material and information flow stream management. The author of the article has described the functions of a production process control system and presented the characteristics of production capacity intensive and extensive reserves. The MRP II/ERP, MES and APS class IT tools supporting the process of production planning, organization and control have also been discussed.

Power Electronic Semiconductor Materials for Automotive and Energy Saving Applications - SiC, GaN, Ga2O3, and Diamond.

PubMed

Wellmann, Peter J

2017-11-17

Power electronics belongs to the future key technologies in order to increase system efficiency as well as performance in automotive and energy saving applications. Silicon is the major material for electronic switches since decades. Advanced fabrication processes and sophisticated electronic device designs have optimized the silicon electronic device performance almost to their theoretical limit. Therefore, to increase the system performance, new materials that exhibit physical and chemical properties beyond silicon need to be explored. A number of wide bandgap semiconductors like silicon carbide, gallium nitride, gallium oxide, and diamond exhibit outstanding characteristics that may pave the way to new performance levels. The review will introduce these materials by (i) highlighting their properties, (ii) introducing the challenges in materials growth, and (iii) outlining limits that need innovation steps in materials processing to outperform current technologies.

Power Electronic Semiconductor Materials for Automotive and Energy Saving Applications – SiC, GaN, Ga2O3, and Diamond

PubMed Central

2017-01-01

Power electronics belongs to the future key technologies in order to increase system efficiency as well as performance in automotive and energy saving applications. Silicon is the major material for electronic switches since decades. Advanced fabrication processes and sophisticated electronic device designs have optimized the silicon electronic device performance almost to their theoretical limit. Therefore, to increase the system performance, new materials that exhibit physical and chemical properties beyond silicon need to be explored. A number of wide bandgap semiconductors like silicon carbide, gallium nitride, gallium oxide, and diamond exhibit outstanding characteristics that may pave the way to new performance levels. The review will introduce these materials by (i) highlighting their properties, (ii) introducing the challenges in materials growth, and (iii) outlining limits that need innovation steps in materials processing to outperform current technologies. PMID:29200530

10 CFR 71.75 - Qualification of special form radioactive material.

Code of Federal Regulations, 2010 CFR

2010-01-01

... temperature of 30°C (86°F) or greater; (v) The process in paragraph (c)(2)(i), (ii), and (iii) of this section... test specified in the International Organization for Standardization document ISO 2919-1980(e), “Sealed...

Recent Progress in Photocatalysis Mediated by Colloidal II-VI Nanocrystals

PubMed Central

Wilker, Molly B; Schnitzenbaumer, Kyle J; Dukovic, Gordana

2012-01-01

The use of photoexcited electrons and holes in semiconductor nanocrystals as reduction and oxidation reagents is an intriguing way of harvesting photon energy to drive chemical reactions. This review focuses on recent research efforts to understand and control the photocatalytic processes mediated by colloidal II-VI nanocrystalline materials, such as cadmium and zinc chalcogenides. First, we highlight how nanocrystal properties govern the rates and efficiencies of charge-transfer processes relevant to photocatalysis. We then describe the use of nanocrystal catalyst heterostructures for fuel-forming reactions, most commonly H2 generation. Finally, we review the use of nanocrystal photocatalysis as a synthetic tool for metal–semiconductor nano-heterostructures. PMID:24115781

Adsorption of Pb(II) from fish sauce using carboxylated cellulose nanocrystal: Isotherm, kinetics, and thermodynamic studies.

PubMed

Wang, Nan; Jin, Ru-Na; Omer, A M; Ouyang, Xiao-Kun

2017-09-01

In the present study, a new adsorbent based on carboxylated cellulose nanocrystal (CCN) was developed for the adsorption of Pb(II) from fish sauce. The prepared adsorbent material was characterized by zeta potential, FT-IR, XRD, and XPS tools. The changes in the morphological structure of the developed CCN surface were evidenced by SEM and TEM. The favorable adsorption conditions were selected by studying the contact time, initial concentration, temperature, and concentration of the used glutamic acid and NaCl. The results indicated that the Langmuir isotherm model agrees very well with experimental adsorption data (R 2 =0.9962) with a maximum adsorption capacity 232.56mg/g of Pb(II) at 293.2K. Additionally, data of the adsorption kinetics follow the pseudo-second-order kinetics (R 2 >0.9990). On the other hand, the thermodynamics studies show that the adsorption process is spontaneous and endothermic. Furthermore, the developed CCN could be regenerated using acid treatment with a good reusability for Pb(II) adsorption. The results clearly indicated that the synthesized CCN could be effectively applied as a new material for Pb(II) adsorption from fish sauce solutions. Copyright © 2017 Elsevier B.V. All rights reserved.

Pb(II) removal from water using Fe-coated bamboo charcoal with the assistance of microwaves.

PubMed

Zhang, Zengsheng; Wang, Xuejiang; Wang, Yin; Xia, Siqing; Chen, Ling; Zhang, Yalei; Zhao, Jianfu

2013-05-01

Bamboo charcoal (BC) was used as starting material to prepare iron-modified bamboo charcoal (Fe-MBC) by its impregnation in FeCl3 and HNO3 solutions simultaneously, followed by microwave heating. The material can be used as an adsorbent for Pb(II) contaminants removal in water. The composites were prepared with Fe molar concentration of 0.5, 1.0 and 2.0 mol/L and characterized by means of N2 adsorption-desorption isotherms, X-ray diffraction spectroscopy (XRD), scanning electron microscopy coupled with energy dispersive X-ray spectrometry (SEM-EDS), Fourier transform infrared (FT-IR) and point of zero charge (pH(pzc)) measurements. Nitrogen adsorption analyses showed that the BET specific surface area and total pore volume increased with iron impregnation. The adsorbent with Fe molar concentration of 2 mol/L (2Fe-MBC) exhibited the highest surface area and produced the best pore structure. The Pb(II) adsorption process of 2Fe-MBC and BC were evaluated in batch experiments and 2Fe-MBC showed an excellent adsorption capability for removal Pb(II). The adsorption of Pb(II) strongly depended on solution pH, with maximum values at pH 5.0. The ionic strength had a significant effect on the adsorption at pH < 6.0. The adsorption isotherms followed the Langmuir isotherm model well, and the maximum adsorption capacity for Pb(II) was 200.38 mg/g for 2Fe-MBC. The adsorption processes were well fitted by a pseudo second-order kinetic model. Thermodynamic parameters showed that the adsorption of Pb(II) onto Fe-MBC was feasible, spontaneous, and exothermic under the studied conditions, and the ion exchange mechanism played an significant role. These results have important implications for the design of low-cost and effective adsorbents in the removal of Pb(II) from wastewater.

Extra-terrestrial construction processes - Advancements, opportunities and challenges

NASA Astrophysics Data System (ADS)

Lim, Sungwoo; Prabhu, Vibha Levin; Anand, Mahesh; Taylor, Lawrence A.

2017-10-01

Government space agencies, including NASA and ESA, are conducting preliminary studies on building alternative space-habitat systems for deep-space exploration. Such studies include development of advanced technologies for planetary surface exploration, including an in-depth understanding of the use of local resources. Currently, NASA plans to land humans on Mars in the 2030s. Similarly, other space agencies from Europe (ESA), Canada (CSA), Russia (Roscosmos), India (ISRO), Japan (JAXA) and China (CNSA) have already initiated or announced their plans for launching a series of lunar missions over the next decade, ranging from orbiters, landers and rovers for extended stays on the lunar surface. As the Space Odyssey is one of humanity's oldest dreams, there has been a series of research works for establishing temporary or permanent settlement on other planetary bodies, including the Moon and Mars. This paper reviews current projects developing extra-terrestrial construction, broadly categorised as: (i) ISRU-based construction materials; (ii) fabrication methods; and (iii) construction processes. It also discusses four categories of challenges to developing an appropriate construction process: (i) lunar simulants; (ii) material fabrication and curing; (iii) microwave-sintering based fabrication; and (iv) fully autonomous and scaled-up construction processes.

The in situ synthesis of PbS nanocrystals from lead(II) n-octylxanthate within a 1,3-diisopropenylbenzene–bisphenol A dimethacrylate sulfur copolymer

PubMed Central

Bear, J. C.; Mayes, A. G.; Parkin, I. P.; O'Brien, P.

2017-01-01

The synthesis of lead sulfide nanocrystals within a solution processable sulfur ‘inverse vulcanization’ polymer thin film matrix was achieved from the in situ thermal decomposition of lead(II) n-octylxanthate, [Pb(S2COOct)2]. The growth of nanocrystals within polymer thin films from single-source precursors offers a faster route to networks of nanocrystals within polymers when compared with ex situ routes. The ‘inverse vulcanization’ sulfur polymer described herein contains a hybrid linker system which demonstrates high solubility in organic solvents, allowing solution processing of the sulfur-based polymer, ideal for the formation of thin films. The process of nanocrystal synthesis within sulfur films was optimized by observing nanocrystal formation by X-ray photoelectron spectroscopy and X-ray diffraction. Examination of the film morphology by scanning electron microscopy showed that beyond a certain precursor concentration the nanocrystals formed were not only within the film but also on the surface suggesting a loading limit within the polymer. We envisage this material could be used as the basis of a new generation of materials where solution processed sulfur polymers act as an alternative to traditional polymers. PMID:28878986

Postsynthetic Improvement of the Physical Properties in a Metal-Organic Framework through a Single Crystal to Single Crystal Transmetallation.

PubMed

Grancha, Thais; Ferrando-Soria, Jesús; Zhou, Hong-Cai; Gascon, Jorge; Seoane, Beatriz; Pasán, Jorge; Fabelo, Oscar; Julve, Miguel; Pardo, Emilio

2015-05-26

A single crystal to single crystal transmetallation process takes place in the three-dimensional (3D) metal-organic framework (MOF) of formula Mg(II) 2 {Mg(II) 4 [Cu(II) 2 (Me3 mpba)2 ]3 }⋅45 H2 O (1; Me3 mpba(4-) =N,N'-2,4,6-trimethyl-1,3-phenylenebis(oxamate)). After complete replacement of the Mg(II) ions within the coordination network and those hosted in the channels by either Co(II) or Ni(II) ions, 1 is transmetallated to yield two novel MOFs of formulae Co2 (II) {Co(II) 4 [Cu(II) 2 (Me3 mpba)2 ]3 }⋅56 H2 O (2) and Ni2 (II) {Ni(II) 4 [Cu(II) 2 (Me3 mpba)2 ]3 }⋅ 54 H2 O (3). This unique postsynthetic metal substitution affords materials with higher structural stability leading to enhanced gas sorption and magnetic properties. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Study of the adsorption of mercury (II) on lignocellulosic materials under static and dynamic conditions.

PubMed

Arias Arias, Fabian E; Beneduci, Amerigo; Chidichimo, Francesco; Furia, Emilia; Straface, Salvatore

2017-08-01

WHO has declared mercury as one of the most dangerous pollutants for human health. Unfortunately, several cases of rivers and aquifers contaminated by mercury inevitably poses the problem on how to remediate them. Considerable efforts are being addressed to develop cost-effective methodologies, among which the use of low-cost adsorbing materials. In this paper, the adsorption performances of an alternative lignocellulosic material derived from the Spanish broom plant, are presented. This plant is widely diffused in the world and its usage for Hg(II) removal from water in real working conditions requires only minimal pretreatment steps. A thoroughly investigation on the kinetics and thermodynamics of Hg(II) adsorption on Spanish broom is presented, by using Hg(II) polluted aqueous solutions specifically prepared in order to simulate typical groundwater conditions. Several batch experiments, under static conditions, were carried out in order to evaluate the effect of pH, contact time, adsorbent dosage, initial concentration, temperature. A maximum adsorption capacity of 20 mg L -1 can be obtained at pH 5, following a pseudo second order kinetics. Moreover, adsorption experiments in dynamic conditions were carried out using Spanish broom filters. Interestingly, a systematic, unconventional double S-shape breakthrough curve was observed under different experimental conditions, revealing the occurrence of two adsorption processes with different time scales. This behavior has been fitted by a bimodal Thomas model which, unlike the single Thomas fitting, gives satisfactory results with the introduction of a new parameter related to the fraction of surface active sites involved in the adsorption processes. Copyright © 2017 Elsevier Ltd. All rights reserved.

Historical generations and psychology. The case of the Great Depression and World War II.

PubMed

Rogler, Lloyd H

2002-12-01

The author assembles a theory of historical generations from dispersed sources in the social and behavioral sciences and in the humanities, differentiates the theory from formulations of other generation concepts, and applies it to central features in the lives of persons in the generation of the Great Depression and World War II. The application of the theory to historical materials explains how a commitment to social interdependence emerged as the signature orientation of the generation of the Great Depression and World War II. Challenges to the perspective of contextualism stem from the theory's hypotheses about linkages that mediate between cataclysmic events and psychological processes, the influence of historical generations on many of psychology's everyday concerns, and instructive comparisons with a body of growing research on processes involving adaptations to different cultures.

Technology of welding aluminum alloys-II

NASA Technical Reports Server (NTRS)

1978-01-01

Step-by-step procedures were developed for high integrity manual and machine welding of aluminum alloys. Detailed instructions are given for each step with tables and graphs to specify materials and dimensions. Throughout work sequence, processing procedure designates manufacturing verification points and inspection points.

Astrophysics with Extraterrestrial Materials

NASA Astrophysics Data System (ADS)

Nittler, Larry R.; Ciesla, Fred

2016-09-01

Extraterrestrial materials, including meteorites, interplanetary dust, and spacecraft-returned asteroidal and cometary samples, provide a record of the starting materials and early evolution of the Solar System. We review how laboratory analyses of these materials provide unique information, complementary to astronomical observations, about a wide variety of stellar, interstellar and protoplanetary processes. Presolar stardust grains retain the isotopic compositions of their stellar sources, mainly asymptotic giant branch stars and Type II supernovae. They serve as direct probes of nucleosynthetic and dust formation processes in stars, galactic chemical evolution, and interstellar dust processing. Extinct radioactivities suggest that the Sun's birth environment was decoupled from average galactic nucleosynthesis for some tens to hundreds of Myr but was enriched in short-lived isotopes from massive stellar winds or explosions shortly before or during formation of the Solar System. Radiometric dating of meteorite components tells us about the timing and duration over which solar nebula solids were assembled into the building blocks of the planets. Components of the most primitive meteoritical materials provide further detailed constraints on the formation, processing, and transport of material and associated timescales in the Sun's protoplanetary disk as well as in other forming planetary systems.

Multifunctional Nanomaterials: Design, Synthesis and Application Properties.

PubMed

Martinelli, Marisa; Strumia, Miriam Cristina

2017-02-07

The immense scope of variation in dendritic molecules (hyper-branching, nano-sized, hydrophobicity/hydrophilicity, rigidity/flexibility balance, etc.) and their versatile functionalization, with the possibility of multivalent binding, permit the design of highly improved, novel materials. Dendritic-based materials are therefore viable alternatives to conventional polymers. The overall aim of this work is to show the advantages of dendronization processes by presenting the synthesis and characterization of three different dendronized systems: (I) microbeads of functionalized chitosan; (II) nanostructuration of polypropylene surfaces; and (III) smart dendritic nanogels. The particular properties yielded by these systems could only be achieved thanks to the dendronization process.

Experimental investigation of CNT effect on curved beam strength and interlaminar fracture toughness of CFRP laminates

NASA Astrophysics Data System (ADS)

Arca, M. A.; Coker, D.

2014-06-01

High mechanical properties and light weight structures of composite materials and advances in manufacturing processes have increased the use of composite materials in the aerospace and wind energy industries as a primary load carrying structures in complex shapes. However, use of composite materials in complex geometries such as L-shaped laminates creates weakness at the radius which causes delamination. Carbon nanotubes (CNTs) is preferred as a toughening materials in composite matrices due to their high mechanical properties and aspect ratios. However, effect of CNTs on curved beam strength (CBS) is not investigated in literature comprehensively. The objective of this study is to investigate the effect of CNT on Mode I and Mode II fracture toughness and CBS. L-shaped beams are fabric carbon/epoxy composite laminates manufactured by hand layup technique. Curved beam composite laminates were subjected to four point bending loading according to ASTM D6415/D6415M-06a. Double cantilever beam (DCB) tests and end notch flexure (ENF) tests were conducted to determine mode-I and mode-II fracture toughness, respectively. Preliminary results show that 3% CNT addition to the resin increased the mode-I fracture toughness by %25 and mode-II fracture toughness by %10 compared to base laminates. In contrast, no effect on curved beam strength was found.

Biosorption of copper by marine algae Gelidium and algal composite material in a packed bed column.

PubMed

Vilar, Vítor J P; Botelho, Cidália M S; Loureiro, José M; Boaventura, Rui A R

2008-09-01

Marine algae Gelidium and algal composite material were investigated for the continuous removal of Cu(II) from aqueous solution in a packed bed column. The biosorption behaviour was studied during one sorption-desorption cycle of Cu(II) in the flow through column fed with 50 and 25 mg l(-1) of Cu(II) in aqueous solution, at pH 5.3, leading to a maximum uptake capacity of approximately 13 and 3 mg g(-1), respectively, for algae Gelidium and composite material. The breakthrough time decreases as the inlet copper concentration increases, for the same flow rate. The pH of the effluent decreases over the breakthrough time of copper ions, which indicates that ion exchange is one of the mechanisms involved in the biosorption process. Temperature has little influence on the metal uptake capacity and the increase of the ionic strength reduces the sorption capacity, decreasing the breakthrough time. Desorption using 0.1M HNO(3) solution was 100% effective. After two consecutive sorption-desorption cycles no changes in the uptake capacity of the composite material were observed. A mass transfer model including film and intraparticle resistances, and the equilibrium relationship, for adsorption and desorption, was successfully applied for the simulation of the biosorption column performance.

Biosorption of Cr (VI), Cr (III), Pb (II) and Cd (II) from aqueous solutions by Sargassum wightii and Caulerpa racemosa algal biomass

NASA Astrophysics Data System (ADS)

Tamilselvan, Narayanaswamy; Saurav, Kumar; Kannabiran, Krishnan

2012-03-01

Heavy metal pollution is one of the most important environmental problems today. Biosorption is an innovative technology that employs biological materials to accumulate heavy metals from waste water through metabolic process or physicochemical pathways of uptake. Even though several physical and chemical methods are available for removal of heavy metals, currently many biological materials such as bacteria, algae, yeasts and fungi have been widely used due to their good performance, low cost and large quantity of availability. The aim of the present study is to explore the biosorption of toxic heavy metals, Cr(VI), Cr(III), Pb(II) and Cd(II) by algal biomass obtained from algae Sargassum wightii (brown) and Caulerpa racemosa (green). Biosorption of algal biomass was found to be biomass concentration- and pH-dependent, while the maximal biosorption was found at pH 5.0 and with the metal concentration of 100 mg L-1. S. wightii showed the maximal metal biosorption at the biomass concentration of 25 g L-1, followed by C. racemosa with the maximal biosorption at 30 g L-1. S. wightii showed 78% biosorption of Cr(VI), Cr(III), Pb(II) and Cd(II) ions. C. racemosa exhibited 85% biosorption of Cd(II) and Cr(VI), and 50% biosorption of Cr(III) and Pb(II). The results of our study suggest that seaweed biomass can be used efficiently for biosorption of heavy metals.

Viability of thin wall tube forming of ATF FeCrAl

DOE Office of Scientific and Technical Information (OSTI.GOV)

Maloy, Stuart Andrew; Aydogan, Eda; Anderoglu, Osman

Fabrication of thin walled tubing of FeCrAl alloys is critical to its success as a candidate enhanced accident-tolerant fuel cladding material. Alloys that are being investigated are Generation I and Generation II FeCrAl alloys produced at ORNL and an ODS FeCrAl alloy, MA-956 produced by Special Metals. Gen I and Gen II FeCrAl alloys were provided by ORNL and MA-956 was provided by LANL (initially produced by Special Metals). Three tube development efforts were undertaken. ORNL led the FeCrAl Gen I and Gen II alloy development and tube processing studies through drawing tubes at Rhenium Corporation. LANL received alloys frommore » ORNL and led tube processing studies through drawing tubes at Century Tubing. PNNL led the development of tube processing studies on MA-956 through pilger processing working with Sandvik Corporation. A summary of the recent progress on tube development is provided in the following report and a separate ORNL report: ORNL/TM-2015/478, “Development and Quality Assessments of Commercial Heat Production of ATF FeCrAl Tubes”.« less

Nuclear Technology Series. Course 17: Radiation Protection II.

ERIC Educational Resources Information Center

Center for Occupational Research and Development, Inc., Waco, TX.

This technical specialty course is one of thirty-five courses designed for use by two-year postsecondary institutions in five nuclear technician curriculum areas: (1) radiation protection technician, (2) nuclear instrumentation and control technician, (3) nuclear materials processing technician, (4) nuclear quality-assurance/quality-control…

40 CFR 65.143 - Closed vent systems.

Code of Federal Regulations, 2010 CFR

2010-07-01

... storage vessel, process vent, transfer rack, or equipment leaks. (1) Collection of emissions. Each closed... material from a storage vessel, transfer rack or equipment leaks. Inspection records shall be generated as... (B) Conduct annual visual inspections for visible, audible, or olfactory indications of leaks. (ii...

Nuclear Technology Series. Course 34: Control Systems II.

ERIC Educational Resources Information Center

Center for Occupational Research and Development, Inc., Waco, TX.

This technical specialty course is one of thirty-five courses designed for use by two-year postsecondary institutions in five nuclear technician curriculum areas: (1) radiation protection technician, (2) nuclear instrumentation and control technician, (3) nuclear materials processing technician, (4) nuclear quality-assurance/quality-control…

BIBLIOGRAPHY ON LEARNING PROCESS. SUPPLEMENT II.

ERIC Educational Resources Information Center

Harvard Univ., Cambridge, MA. Graduate School of Education.

THIS SUPPLEMENTARY BIBLIOGRAPHY LISTS MATERIALS ON VARIOUS FACETS OF HUMAN LEARNING. APPROXIMATELY 60 UNANNOTATED REFERENCES ARE PROVIDED FOR DOCUMENTS DATING FROM 1954 TO 1966. JOURNAL ARTICLES, BOOKS, RESEARCH REPORTS, AND CONFERENCE PAPERS ARE LISTED. SOME SUBJECT AREAS INCLUDED ARE (1) LEARNING PARAMETERS AND ABILITY, (2) RETENTION AND…

Exploratory study of hot-in-place recycling of asphalt pavements, volume II : appendices.

DOT National Transportation Integrated Search

1994-11-01

Hot-in-place recycling (HIR) is a method for rehabilitation of asphalt pavements. Potential for cost savings and resource preservation are high because existing pavement materials are processed on-site, with only the addition of small amounts of recy...

The r-process Pattern of a Bright, Highly r-process-enhanced Metal-poor Halo Star at [Fe/H] ∼ ‑2

NASA Astrophysics Data System (ADS)

Sakari, Charli M.; Placco, Vinicius M.; Hansen, Terese; Holmbeck, Erika M.; Beers, Timothy C.; Frebel, Anna; Roederer, Ian U.; Venn, Kim A.; Wallerstein, George; Davis, Christopher Evan; Farrell, Elizabeth M.; Yong, David

2018-02-01

A high-resolution spectroscopic analysis is presented for a new highly r-process-enhanced ([Eu/Fe] = 1.27, [Ba/Eu] = ‑0.65), very metal-poor ([Fe/H] = ‑2.09), retrograde halo star, RAVE J153830.9–180424, discovered as part of the R-Process Alliance survey. At V = 10.86, this is the brightest and most metal-rich r-II star known in the Milky Way halo. Its brightness enables high-S/N detections of a wide variety of chemical species that are mostly created by the r-process, including some infrequently detected lines from elements like Ru, Pd, Ag, Tm, Yb, Lu, Hf, and Th, with upper limits on Pb and U. This is the most complete r-process census in a very metal-poor r-II star. J1538–1804 shows no signs of s-process contamination, based on its low [Ba/Eu] and [Pb/Fe]. As with many other r-process-enhanced stars, J1538–1804's r-process pattern matches that of the Sun for elements between the first, second, and third peaks, and does not exhibit an actinide boost. Cosmo-chronometric age-dating reveals the r-process material to be quite old. This robust main r-process pattern is a necessary constraint for r-process formation scenarios (of particular interest in light of the recent neutron star merger, GW170817), and has important consequences for the origins of r-II stars. Additional r-I and r-II stars will be reported by the R-Process Alliance in the near future.

Sulfur‐Limonene Polysulfide: A Material Synthesized Entirely from Industrial By‐Products and Its Use in Removing Toxic Metals from Water and Soil

PubMed Central

Crockett, Michael P.; Evans, Austin M.; Worthington, Max J. H.; Albuquerque, Inês S.; Slattery, Ashley D.; Gibson, Christopher T.; Campbell, Jonathan A.; Lewis, David A.; Bernardes, Gonçalo J. L.

2015-01-01

Abstract A polysulfide material was synthesized by the direct reaction of sulfur and d‐limonene, by‐products of the petroleum and citrus industries, respectively. The resulting material was processed into functional coatings or molded into solid devices for the removal of palladium and mercury salts from water and soil. The binding of mercury(II) to the sulfur‐limonene polysulfide resulted in a color change. These properties motivate application in next‐generation environmental remediation and mercury sensing. PMID:26481099

The target material influence on the current pulse during high power pulsed magnetron sputtering

NASA Astrophysics Data System (ADS)

Moens, Filip; Konstantinidis, Stéphanos; Depla, Diederik

2017-10-01

The current-time characteristic during high power pulsed magnetron sputtering is measured under identical conditions for seventeen different target materials. Based on physical processes such as gas rarefaction, ion-induced electron emission, and electron impact ionization, two test parameters were derived that significantly correlate with specific features of the current-time characteristic: i) the peak current is correlated to the momentum transfer between the sputtered material and the argon gas, ii) while the observed current plateau after the peak is connected to the metal ionization rate.

New silver-halide-sensitized gelatin material: the influence of bleaches on holograms

NASA Astrophysics Data System (ADS)

Zhang, Weiping; Pang, Lin; Guo, Lurong

1996-12-01

A new high-resolution-silver-halide (HRSH-II) material was produced, which has proper initial hardness for fabricating silver halide sensitized gelatin (SHSG) holograms. That would avoid high noise by seeking the gelatin in hot water. With different alkali halide component in B solution and its concentration (the ratio B/A), experiments were presented about bleaching effect with R-10 on processing for SHSG derived from this new material. High diffraction efficiency, as high as 81%, was achieved. Some of the observations are discussed.

Refining of Military Jet Fuels from Shale Oil. Part II. Volume III. Above Ground Shale Oil Process Data.

DTIC Science & Technology

1982-03-01

system. Regenerator flue gas composi- tion, spent catalyst carbon content and regenerated cata- lyst content are monitored for material balance purposes...and good material balance closures obtained. During each run pro- duct gas samples, regenerator flue gas samples, spent and -85- regenerated...TEMPERATURE DEPENDENCE OF DENITROGENATION AT 2 LHSV ON CO/MO ......................... 26 111-2 TEMPERATURE DEPENDENCE OF DESULFURIZATION AT 2 LHSV ON

Phase Transformations and Microstructural Evolution: Part II

DOE PAGES

Clarke, Amy Jean

2015-10-30

The activities of the Phase Transformations Committee of the Materials Processing & Manufacturing Division (MPMD) of The Minerals, Metals & Materials Society (TMS) are oriented toward understanding the fundamental aspects of phase transformations. Emphasis is placed on the thermodynamic driving forces for phase transformations, the kinetics of nucleation and growth, interfacial structures and energies, transformation crystallography, surface reliefs, and, above all, the atomic mechanisms of phase transformations. Phase transformations and microstructural evolution are directly linked to materials processing, properties, and performance. In this issue, aspects of liquid–solid and solid-state phase transformations and microstructural evolution are highlighted. Many papers in thismore » issue are highlighted by this paper, giving a brief summary of what they bring to the scientific community.« less

Carbon-carbon mirrors for exoatmospheric and space applications

NASA Astrophysics Data System (ADS)

Krumweide, Duane E.; Wonacott, Gary D.; Woida, Patrick M.; Woida, Rigel Q.; Shih, Wei

2007-09-01

The cost and leadtime associated with beryllium has forced the MDA and other defense agencies to look for alternative materials with similar structural and thermal properties. The use of carbon-carbon material, specifically in optical components has been demonstrated analytically in prior SBIR work at San Diego Composites. Carbon-carbon material was chosen for its low in-plane and through-thickness CTE (athermal design), high specific stiffness, near-zero coefficient of moisture expansion, availability of material (specifically c-c honeycomb for lightweight substrates), and compatibility with silicon monoxide (SiO) and silicon dioxide (SiO II) coatings. Subsequent development work has produced shaped carbon-carbon sandwich substrates which have been ground, polished, coated and figured using traditional optical processing. Further development has also been done on machined monolithic carbon-carbon mirror substrates which have also been processed using standard optical finishing techniques.

Heat-Affected Zone Liquation Cracking Resistance of Friction Stir Processed Aluminum-Copper Alloy AA 2219

NASA Astrophysics Data System (ADS)

Karthik, G. M.; Janaki Ram, G. D.; Kottada, Ravi Sankar

2017-04-01

In the current work, the effect of friction stir processing on heat-affected zone (HAZ) liquation cracking resistance of aluminum-copper alloy AA 2219 was evaluated. In Gleeble hot-ductility tests and longitudinal Varestraint tests, the FSPed material, despite its very fine dynamically recrystallized equiaxed grain structure, showed considerably higher susceptibility to HAZ liquation cracking when compared to the base material. Detailed microstructural studies showed that the increased cracking susceptibility of the FSPed material is due to (i) increase in the amount of liquating θ phase (equilibrium Al2Cu) and (ii) increase in the population of grain boundary θ particles. An important learning from the current work is that, in certain materials like alloy 2219, the use of FSP as a pretreatment to fusion welding can be counterproductive.

Composite materials formed with anchored nanostructures

DOEpatents

Seals, Roland D; Menchhofer, Paul A; Howe, Jane Y; Wang, Wei

2015-03-10

A method of forming nano-structure composite materials that have a binder material and a nanostructure fiber material is described. A precursor material may be formed using a mixture of at least one metal powder and anchored nanostructure materials. The metal powder mixture may be (a) Ni powder and (b) NiAl powder. The anchored nanostructure materials may comprise (i) NiAl powder as a support material and (ii) carbon nanotubes attached to nanoparticles adjacent to a surface of the support material. The process of forming nano-structure composite materials typically involves sintering the mixture under vacuum in a die. When Ni and NiAl are used in the metal powder mixture Ni.sub.3Al may form as the binder material after sintering. The mixture is sintered until it consolidates to form the nano-structure composite material.

Prediction of equilibrium parameters of adsorption of lead (II) ions onto diatomite

NASA Astrophysics Data System (ADS)

Salman, Taylan; Ardalı, Yüksel; Gamze Turan, N.

2013-04-01

Heavy metals from industrial wastewaters are one of the most important environmental issues to be solved today. Due to their toxicity and nonbiodegradable nature, heavy metals cause environmental and public health problems. Various techniques have been developed to remove heavy metals from aqueous solutions. These include chemical precipitation, reverse osmosis, ion Exchange and adsorption. Among them, adsorption is considered to be a particularly competitive and effective process for the removal of heavy metals from aqueous solutions. There is growing interest in using low cost, commercially available materials for the adsorption of heavy metals. Diatomite is a siliceous sedimentary rock having an amorphous form of silica (SiO2. nH2O) containing a small amount of microcrystalline material. It has unique combination of physical and chemical properties such as high porosity, high permeability, small particle size, large surface area, and low thermal conductivity. In addition, it is available in Turkey and in various locations around the world. Therefore, diatomite has been successfully used as adsorbent for the removal of heavy metals. The aim of the study is to investigate the adsorption properties of diatomite. The equilibrium adsorption data were applied to the Langmuir, Freundlich and Dubinin-Radushkevic (D-R) isotherm models. Adsorption experiments were performed under batch process, using Pb (II) initial concentration, pH of solution and contact time as variables. The results demonstrated that the adsorption of Pb (II) was strongly dependent on pH of solution. The effect of pH on adsorption of Pb(II) on diatomite was conducted by varying pH from 2 to 12 at 20 oC. In the pH range of 2.0-4.0, the adsorption percentage increases slightly as the pH increasing. At pH>4, the adsorption percentage decreases with increasing pH because hydrolysis product and the precipitation begin to play an important role in the sorption of Pb (II). At pH4, the maximum adsorption capacity of diatomite was found as 26.158 mg/g. The adsorption isotherms of Pb (II) on diatomite can be described well by the Freundlich model. The high adsorption capacity of diatomite makes it suitable low-cost material in the removal of Pb (II) from aqueous solutions.

Nuclear Technology Series. Course 32: Nondestructive Examination (NDE) Techniques II.

ERIC Educational Resources Information Center

Center for Occupational Research and Development, Inc., Waco, TX.

This technical specialty course is one of thirty-five courses designed for use by two-year postsecondary institutions in five nuclear technician curriculum areas: (1) radiation protection technician, (2) nuclear instrumentation and control technician, (3) nuclear materials processing technician, (4) nuclear quality-assurance/quality-control…

The Logistics Planning Process of the Far East Air Material Command during the Korean War

DTIC Science & Technology

1988-09-01

Figures . . ........... ........ vii Abstract ........... ........................ viii I. Introduction to the Research ............. 1 Overview ...31 Particular Method . . . ........... 32 II. The National Defense Planning Structure. . . ... 34 Overview ...Air Materiel Command’s Logistics Plans and Policy Making Response to Korean Tasking . . . . ........ 83 Overview

40 CFR 725.428 - Requirements for the Tier II exemption.

Code of Federal Regulations, 2010 CFR

2010-07-01

... SUBSTANCES CONTROL ACT REPORTING REQUIREMENTS AND REVIEW PROCESSES FOR MICROORGANISMS General Exemptions for... material meets the criteria under § 725.421. (c) Adequate physical containment and control technologies are used. The criteria listed under § 725.422 for physical containment and control technologies of...

Influence of bone morphogenetic protein and proportion of hydroxyapatite on new bone formation in biphasic calcium phosphate graft: two pilot studies in animal bony defect model.

PubMed

Yun, Pil-Young; Kim, Young-Kyun; Jeong, Kyung-In; Park, Ju-Cheol; Choi, Yeon-Jo

2014-12-01

The purpose of these two pilot studies using animal bony defect models was to evaluate the influence of bone morphogenetic protein (BMP) and proportion of hydroxyapatite (HA)/beta-tricalcium phosphate (β-TCP) in biphasic calcium phosphate (BCP) graft on new bone formation. In this study, four kinds of synthetic osteoconductive bone materials known for bone growth scaffold, OSTEON™II(HA:β-TCP 30:70), OSTEON™III (HA:β-TCP 20:80), OSTEON™II Collagen, and OSTEON™III Collagen, were prepared as BCP graft materials. In pilot study 1, three BCP materials (OSTEON™II, OSTEON™III, and OSTEON™II Collagen) were grafted in rabbit calvarial defects after impregnating in rhBMP-2. OSTEON™II without the rhBMP-2 impregnation was included in the study as the control. The amount of new bone was examined and measured histologically at 2, 4, and 8 weeks. In pilot study 2, four BCP materials (OSTEON™II, OSTEON™III, OSTEON™II Collagen, and OSTEON™III Collagen) were grafted in beagle dog mandibular defects after soaking in the rhBMP-2. The amount of total bone and new bone were measured three-dimensionally using microCT and healing process was examined histologically at 2, 4, and 8 weeks. In pilot study 1, rhBMP-2 impregnated groups showed more new bone formation than the rhBMP-2 free group. In pilot study 2, increased new bone formation was observed in time-dependent manner after graft of BCP and BCP-collagen (OSTEON™II, OSTEON™III, OSTEON™II Collagen, and OSTEON™III Collagen) impregnated with rhBMP-2. Also, BCP with a higher proportion of HA (30% HA) showed more favorable result in new bone formation and space maintenance, especially at the 8 weeks. From the results of the pilot studies, rhBMP-2 played positive roles in new bone formation and BCP could become a scaffold candidate for rhBMP-2 impregnation to induce new bone formation. Moreover, BCP with a higher proportion of HA (30% HA) could be considered more appropriate for rhBMP-2 carrier. Copyright © 2014 European Association for Cranio-Maxillo-Facial Surgery. Published by Elsevier Ltd. All rights reserved.

Structure and transport properties of dense polycrystalline clathrate-II (K,Ba) 16(Ga,Sn) 136 synthesized by a new approach employing SPS

DOE PAGES

Wei, Kaya; Zeng, Xiaoyu; Tritt, Terry M.; ...

2016-08-26

Tin clathrate-II framework-substituted compositions are of current interest as potential thermoelectric materials for medium-temperature applications. A review of the literature reveals different compositions reported with varying physical properties, which depend strongly on the exact composition as well as the processing conditions. We therefore initiated an approach whereby single crystals of two different (K,Ba) 16(Ga,Sn) 136 compositions were first obtained, followed by grinding of the crystals into fine powder for low temperature spark plasma sintering consolidation into dense polycrystalline solids and subsequent high temperature transport measurements. Powder X-ray refinement results indicate that the hexakaidecahedra are empty, K and Ba occupying onlymore » the decahedra. Their electrical properties depend on composition and have very low thermal conductivities. As a result, the structural and transport properties of these materials are compared to that of other Sn clathrate-II compositions.« less

Finite element analysis of the end notched flexure specimen for measuring Mode II fracture toughness

NASA Technical Reports Server (NTRS)

Gillespie, J. W., Jr.; Carlsson, L. A.; Pipes, R. B.

1986-01-01

The paper presents a finite element analysis of the end-notched flexure (ENF) test specimen for Mode II interlaminar fracture testing of composite materials. Virtual crack closure and compliance techniques employed to calculate strain energy release rates from linear elastic two-dimensional analysis indicate that the ENF specimen is a pure Mode II fracture test within the constraints of small deflection theory. Furthermore, the ENF fracture specimen is shown to be relatively insensitive to process-induced cracks, offset from the laminate midplane. Frictional effects are investigated by including the contact problem in the finite element model. A parametric study investigating the influence of delamination length, span, thickness, and material properties assessed the accuracy of beam theory expressions for compliance and strain energy release rate, GII. Finite element results indicate that data reduction schemes based upon beam theory underestimate GII by approximately 20-40 percent for typical unidirectional graphite fiber composite test specimen geometries. Consequently, an improved data reduction scheme is proposed.

Removal of Co(II) from waste water using dry cow dung powder : a green ambrosia to soil

NASA Astrophysics Data System (ADS)

Bagla, Hemlata; Khilnani, Roshan

2015-04-01

Co(II) is one of the hazardous products found in the waste streams. The anthropogenic activities are major sources of Co(II) in our environment. Some of the well-established processes such as chemical precipitation, membrane process, liquid extraction and ion exchange have been applied as a tool for the removal of this metal ion [1]. All the above methods are not considered to be greener due to some of their shortcomings such as incomplete metal ion removal, high requirement of energy and reagents, generation of toxic sludge or other waste materials which in turn require further treatments for their cautious disposal. The present investigation entails the application of dry cow dung powder (DCP) as an indigenous, inexpensive and eco-friendly material for the removal of Co(II) from aqueous medium. DCP, is naturally available bio-organic, complex, polymorphic humified fecal matter of cow and is enriched with minerals, carbohydrates, fats, proteins, bile pigments, aliphatic-aromatic species such as 'Humic acid' (HA), Fulvic acid, Ulmic acid [2,3]. Batch biosorption experiments were conducted employing 60Co(II) as a tracer and effect of various process parameters such as pH (1-8), temperature (283-363K), amount of biosorbent (5-40 g/L), time of equilibration (0-30 min), agitation speed (0-4000 rpm), concentration of initial metal ions (0.5-20 mg/mL) and interfering effect of different organic as well as inorganic salts were studied. The Kinetic studies were carried out employing various models but the best fitting was given by Lagergren Pseudo-second order model [4] with high correlation coefficient R2 value of 0.999 and adsorption capacity of 2.31 mg/g. The thermodynamic parameters for biosorption were also evaluated which indicated spontaneous and exothermic process with high affinity of DCP for Co(II). Many naturally available materials are used for biosorption of hazardous metal pollutants, where most of them are physically or chemically modified. In this research work, DCP has been utilized without pre or post chemical treatment. Thus it manifests the principal of green chemistry and proves to be an eco-friendly biosorbent. References 1. N.S. Barot, H.K. Bagla, Biosorption of Radiotoxic 90Sr by Green adsorbent: Dry Cow Dung Powder, Journal of Radioanalytical and Nuclear Chemistry, 294, pp. 81-86, (2012). 2. N.S. Barot, H.K. Bagla, Eco-friendly waste water treatment by cow-dung powder (Adsorption studies of Cr(III), Cr (VI) & Cd(II) using Tracer Technique), Desalination & Water Treatment, 38(1-3), pp.104-113, (2012). 3. N.S. Barot, R.P. Khilnani, H.K. Bagla, "Biosorptive profile of Synthetic and Natural Humiresin for the remediation of Metallic Water Pollutants", Journal of Radioanalytical and Nuclear Chemistry, 301(1):1-9, (2014). 4. S. Lagergren, Zur theorie der sogenannten adsorption geloster stoffe. Kungliga Svenska Vetenskapsakademiens, Handlingar 24(4):1-39, (1898).

Optimized Gen-II FeCrAl cladding production in large quantity for campaign testing

DOE Office of Scientific and Technical Information (OSTI.GOV)

Yamamoto, Yukinori; Sun, Zhiqian; Pint, Bruce A.

2016-06-03

There are two major objectives in this report; (1) to optimize microstructure control of ATF FeCrAl alloys during tube drawing processes, and (2) to provide an update on the progress of ATF FeCrAl tube production via commercial manufacturers. Experimental efforts have been made to optimize the process parameters balancing the tube fabricability, especially for tube drawing processes, and microstructure control of the final tube products. Lab-scale sheet materials of Gen II FeCrAl alloys (Mo-containing and Nb-containing FeCrAl alloys) were used in the study, combined with a stepwise warm-rolling process and intermediate annealing, aiming to simulate the tube drawing process inmore » a commercial tube manufacturer. The intermediate annealing at 650ºC for 1h was suggested for the tube-drawing process of Mo-containing FeCrAl alloys because it successfully softened the material by recovering the work hardening introduced through the rolling step, without inducing grain coarsening due to recrystallization. The final tube product is expected to have stabilized deformed microstructure providing the improved tensile properties with sufficient ductility. Optimization efforts on Nb-containing FeCrAl alloys focused on the effect of alloying additions and annealing conditions on the stability of deformed microstructure. Relationships between the second-phase precipitates (Fe 2Nb-Laves phase) and microstructure stability are discussed. FeCrAl tube production through commercial tube manufacturers is currently in progress. Three different manufacturers, Century Tubes, Inc. (CTI), Rhenium Alloys, Inc. (RAI), and Superior Tube Company, Inc. (STC), are providing capabilities for cold-drawing, warm-drawing, and HPTR cold-pilgering, respectively. The first two companies are currently working on large quantity tube production (expected 250 ft length) of Gen I model FeCrAl alloy (B136Y3, at CTI) and Gen II (C35M4, at RAI), with the process parameters obtained from the experimental efforts. The expected delivery dates are at the end of July, 2016, and the middle of June, 2016, respectively. Tube production at STC would be the first attempt to apply cold-pilgering to the FeCrAl alloys. Communication has been initiated, and the materials have been machined for the cold-pilgering process.« less

Efficient adsorption of multiple heavy metals with tailored silica aerogel-like materials.

PubMed

Vareda, João P; Durães, Luisa

2017-11-10

Recently developed tailored adsorbents for heavy metal uptake are studied in batch tests with Cu, Pb, Cd, Ni, Cr and Zn, in order to decontaminate polluted environments where these heavy metals are found in solution - water courses and groundwater. The adsorbents feature mercapto or amine-mercapto groups that are capable of complexating the cations. Through the use of equilibrium tests it is found that a remarkably high heavy metal uptake is obtained for all metals (ranging from 84 to 140 mg/g). These uptake values are quite impressive when compared to other adsorbents reported in the literature, which is also due to the double functionalization present in one of the adsorbents. For the best adsorbent, adsorption capacities followed the order Cu(II) > Pb(II) > Zn(II) > Cr(III) > Cd(II) > Ni(II). With these adsorbents, the removal process was fast with most of the metals being removed in less than 1 h. Competitive sorption tests were performed in tertiary mixtures that were based on real world polluted sites. It was found that although competitive sorption occurs, affecting the individual removal of each metal, all the cations in solution still interact with the adsorbent, achieving removal values that make this type of material very interesting for its proposed application.

Simulating neutron star mergers as r-process sources in ultrafaint dwarf galaxies

NASA Astrophysics Data System (ADS)

Safarzadeh, Mohammadtaher; Scannapieco, Evan

2017-10-01

To explain the high observed abundances of r-process elements in local ultrafaint dwarf (UFD) galaxies, we perform cosmological zoom simulations that include r-process production from neutron star mergers (NSMs). We model star formation stochastically and simulate two different haloes with total masses ≈108 M⊙ at z = 6. We find that the final distribution of [Eu/H] versus [Fe/H] is relatively insensitive to the energy by which the r-process material is ejected into the interstellar medium, but strongly sensitive to the environment in which the NSM event occurs. In one halo, the NSM event takes place at the centre of the stellar distribution, leading to high levels of r-process enrichment such as seen in a local UFD, Reticulum II (Ret II). In a second halo, the NSM event takes place outside of the densest part of the galaxy, leading to a more extended r-process distribution. The subsequent star formation occurs in an interstellar medium with shallow levels of r-process enrichment that results in stars with low levels of [Eu/H] compared to Ret II stars even when the maximum possible r-process mass is assumed to be ejected. This suggests that the natal kicks of neutron stars may also play an important role in determining the r-process abundances in UFD galaxies, a topic that warrants further theoretical investigation.

Modeling Neutron stars as r-process sources in Ultra Faint Dwarf galaxies

NASA Astrophysics Data System (ADS)

Safarzadeh, Mohammadtaher; Scannapieco, Evan

2018-06-01

To explain the high observed abundances of r-process elements in local ultrafaint dwarf (UFD) galaxies, we perform cosmological zoom simulations that include r-process production from neutron star mergers (NSMs). We model star formation stochastically and simulate two different haloes with total masses ≈108 M⊙ at z = 6. We find that the final distribution of [Eu/H] versus [Fe/H] is relatively insensitive to the energy by which the r-process material is ejected into the interstellar medium, but strongly sensitive to the environment in which the NSM event occurs. In one halo, the NSM event takes place at the centre of the stellar distribution, leading to high levels of r-process enrichment such as seen in a local UFD, Reticulum II (Ret II). In a second halo, the NSM event takes place outside of the densest part of the galaxy, leading to a more extended r-process distribution. The subsequent star formation occurs in an interstellar medium with shallow levels of r-process enrichment that results in stars with low levels of [Eu/H] compared to Ret II stars even when the maximum possible r-process mass is assumed to be ejected. This suggests that the natal kicks of neutron stars may also play an important role in determining the r-process abundances in UFD galaxies, a topic that warrants further theoretical investigation.

Hazardous Waste Minimization Initiation Decision Report. Volume 1

DTIC Science & Technology

1988-06-01

different treatment and disposal practices for spent caustic materials. In some cases, the material is placed in drums and sent to DRMO for disposal or to a...often available. As at some Navy facilities, waste caustic may be neutralized with spent acid at the process line with the effluent sent to the IWTP...3-111 PART II - Spent Battery Electrolyte .... 3-112 PART III- Battery Acid Sludges ........ 3-113 3.13.3 Disposal of Wastes from Battery Repair and

Delta II Stardust Mission Briefing

NASA Technical Reports Server (NTRS)

1999-01-01

An overview of the Stardust Mission is shown. NASA personnel is seen discussing and explaining the path of the probe. An animated clip is presented to demonstrate how the probe will collect interstellar dust materials, and space particles by using an aerogel. The animation also described the process by which the probe will take photographs of the comets from the on board camera. The dust samples and the photographs will be analyzed in order to learn more about interstellar materials.

34 CFR 642.25 - What is the review process for unsuccessful applicants?

Code of Federal Regulations, 2011 CFR

2011-07-01

...) OFFICE OF POSTSECONDARY EDUCATION, DEPARTMENT OF EDUCATION TRAINING PROGRAM FOR FEDERAL TRIO PROGRAMS How... was not evaluated during the competition may request that the Secretary review the application if— (i... notice inviting applications and the other published application materials for the competition; and (ii...

INSTRUCTIONAL TELEVISION FOR THE FOURTH GRADE. A TEACHER GUIDE SEMESTER II.

ERIC Educational Resources Information Center

PELIKAN, ALFRED; AND OTHERS

PROGRAMS FOR FOURTH GRADE ARE DIVIDED INTO FOUR AREAS--ART, MUSIC PHYSICAL EDUCATION AND SCIENCE. ART LESSONS INCLUDE THE PAPER CONSTRUCTION OF ROCKETS AND SPACESHIPS, FINGER PUPPETS, SANDPAPER PRINTS AND GLASS ADDITIVE PRINTS. EACH LESSON IS PRESENTED COMPLETE WITH PURPOSES, PROCESS AND MEDIUM, SUBJECT, MATERIALS, PROPOSED SEQUENCE, AND…

BASIC Simulation Programs; Volumes I and II. Biology, Earth Science, Chemistry.

ERIC Educational Resources Information Center

Digital Equipment Corp., Maynard, MA.

Computer programs which teach concepts and processes related to biology, earth science, and chemistry are presented. The seven biology problems deal with aspects of genetics, evolution and natural selection, gametogenesis, enzymes, photosynthesis, and the transport of material across a membrane. Four earth science problems concern climates, the…

Activated Sludge. Selected Instructional Activities and References. Instructional Resources Monograph Series.

ERIC Educational Resources Information Center

Shepard, Clinton L.; Walasek, James B.

This monograph contains a variety of selected materials related to wastewater treatment and water quality education and instruction. Part I presents a brief discussion of the activated sludge process in wastewater treatment operations. Part II, Instructional Units, contains selected portions of existing programs which may be utilized in…

Nanocrystal solar cells processed from solution

DOEpatents

Alivisatos, A. Paul; Gur, Ilan; Milliron, Delia

2013-05-14

A photovoltaic device having a first electrode layer, a high resistivity transparent film disposed on the first electrode, a second electrode layer, and an inorganic photoactive layer disposed between the first and second electrode layers, wherein the inorganic photoactive layer is disposed in at least partial electrical contact with the high resistivity transparent film, and in at least partial electrical contact with the second electrode. The photoactive layer has a first inorganic material and a second inorganic material different from the first inorganic material, wherein the first and second inorganic materials exhibit a type II band offset energy profile, and wherein the photoactive layer has a first population of nanostructures of a first inorganic material and a second population of nanostructures of a second inorganic material.

On stress field near a stationary crack tip

NASA Technical Reports Server (NTRS)

Nemat-Nasser, S.; Obata, M.

1984-01-01

It is well known that the stress and elastic-plastic deformation fields near a crack tip have important roles in the corresponding fracture process. For elastic-perfectly-plastic solids, different solutions are given in the literature. In this work several of these solutions are examined and compared for Mode I (tension), Mode II (shear), and mixed Modes I and II loading conditions in plane strain. By consideration of the dynamic solution, it is shown that the assumption that the material is yielding all around a crack tip may not be reasonable in all cases. By admitting the existence of some elastic sectors, continuous stress fields are obtained even for mixed Modes I and II.

CO2 lasers and applications II; Proceedings of the Third European Congress on Optics, The Hague, Netherlands, Mar. 12-14, 1990

NASA Technical Reports Server (NTRS)

Opower, Hans (Editor)

1990-01-01

Recent advances in CO2 laser technology and its applications are examined. Topics discussed include the excitation of CO2 lasers by microwave discharge, a compact RF-excited 12-kW CO2 laser, a robotic laser for three-dimensional cutting and welding, three-dimensional CO2-laser material processing with gantry machine systems, and a comparison of hollow metallic waveguides and optical fibers for transmitting CO2-laser radiation. Consideration is given to an aerodynamic window with a pump cavity and a supersonic jet, cutting and welding Al using a high-repetition-rate pulsed CO2 laser, speckle reduction in CO2 heterodyne laser radar systems, high-power-laser float-zone crystal growth, melt dynamics in surface processing with laser radiation, laser hardfacing, surface melting of AlSi10Mg with CO2 laser radiation, material processing with Cu-vapor lasers, light-induced flow at a metal surface, and absorption measurements in high-power CW CO2-laser processing of materials.

Luminescent zinc(ii) and copper(i) complexes for high-performance solution-processed monochromic and white organic light-emitting devices.

PubMed

Cheng, Gang; So, Gary Kwok-Ming; To, Wai-Pong; Chen, Yong; Kwok, Chi-Chung; Ma, Chensheng; Guan, Xiangguo; Chang, Xiaoyong; Kwok, Wai-Ming; Che, Chi-Ming

2015-08-01

The synthesis and spectroscopic properties of luminescent tetranuclear zinc(ii) complexes of substituted 7-azaindoles and a series of luminescent copper(i) complexes containing 7,8-bis(diphenylphosphino)-7,8-dicarba- nido -undecaborate ligand are described. These complexes are stable towards air and moisture. Thin film samples of the luminescent copper(i) complexes in 2,6-dicarbazolo-1,5-pyridine and zinc(ii) complexes in poly(methyl methacrylate) showed emission quantum yields of up to 0.60 (for Cu-3 ) and 0.96 (for Zn-1 ), respectively. Their photophysical properties were examined by ultrafast time-resolved emission spectroscopy, temperature dependent emission lifetime measurements and density functional theory calculations. Monochromic blue and orange solution-processed OLEDs with these Zn(ii) and Cu(i) complexes as light-emitting dopants have been fabricated, respectively. Maximum external quantum efficiency (EQE) of 5.55% and Commission Internationale de l'Eclairage (CIE) coordinates of (0.16, 0.19) were accomplished with the optimized Zn-1 -OLED while these values were, respectively 15.64% and (0.48, 0.51) for the optimized Cu-3 -OLED. Solution-processed white OLEDs having maximum EQE of 6.88%, CIE coordinates of (0.42, 0.44), and colour rendering index of 81 were fabricated by using these luminescent Zn(ii) and Cu(i) complexes as blue and orange light-emitting dopant materials, respectively.

The electric and thermoelectric properties of Cu(II)-Schiff base nano-complexes

NASA Astrophysics Data System (ADS)

Ibrahim, E. M. M.; Abdel-Rahman, Laila H.; Abu-Dief, Ahmed M.; Elshafaie, A.; Hamdan, Samar Kamel; Ahmed, A. M.

2018-05-01

The physical properties, such as electric and optical properties, of metal-Schiff base complexes have been widely investigated. However, their thermoelectric (TE) properties remain unreported. This work presents Cu(II)-Schiff base complexes as promising materials for TE power generation. Therefore, three Cu(II)-Schiff base complexes (namely, [Cu(C32H22N4O2)].3/2H2O, [Cu(C23H17N4O7Br)], and [Cu(C27H22N4O8)].H2O) have been synthesized in nanosized scale. The electric and TE properties have been studied and comprehensive discussions have been presented to promote the nano-complexes (NCs) practical applications in the field of TE power generation. The electrical measurements confirm that the NCs are semiconductors and the electrical conduction process is governed by intermolecular and intramolecular transfer of the charge carriers. The TE measurements reveal that the Cu(II)-Schiff base NCs are nondegenerate P-type semiconductors. The measured Seebeck coefficient values were higher compared to the values reported in previous works for other organic materials indicating that the complexes under study are promising candidates for theremoelectric applications if the electrical conductivity could be enhanced.

Modifications in the AA5083 Johnson-Cook Material Model for Use in Friction Stir Welding Computational Analyses

NASA Astrophysics Data System (ADS)

Grujicic, M.; Pandurangan, B.; Yen, C.-F.; Cheeseman, B. A.

2012-11-01

Johnson-Cook strength material model is frequently used in finite-element analyses of various manufacturing processes involving plastic deformation of metallic materials. The main attraction to this model arises from its mathematical simplicity and its ability to capture the first-order metal-working effects (e.g., those associated with the influence of plastic deformation, rate of deformation, and the attendant temperature). However, this model displays serious shortcomings when used in the engineering analyses of various hot-working processes (i.e., those utilizing temperatures higher than the material recrystallization temperature). These shortcomings are related to the fact that microstructural changes involving: (i) irreversible decrease in the dislocation density due to the operation of annealing/recrystallization processes; (ii) increase in grain-size due to high-temperature exposure; and (iii) dynamic-recrystallization-induced grain refinement are not accounted for by the model. In this study, an attempt is made to combine the basic physical-metallurgy principles with the associated kinetics relations to properly modify the Johnson-Cook material model, so that the model can be used in the analyses of metal hot-working and joining processes. The model is next used to help establish relationships between process parameters, material microstructure and properties in friction stir welding welds of AA5083 (a non-age-hardenable, solid-solution strengthened, strain-hardened/stabilized Al-Mg-Mn alloy).

Ground-based research of crystal growth of II-VI compound semiconductors by physical vapor transport

NASA Technical Reports Server (NTRS)

Volz, M. P.; Gillies, D. C.; Szofran, F. R.; Lehoczky, S. L.; Su, Ching-Hua; Sha, Yi-Gao; Zhou, W.; Dudley, M.; Liu, Hao-Chieh; Brebrick, R. F.;

Constitutional dynamic self-sensing in a zinc(II)/polyiminofluorenes system.

PubMed

Giuseppone, Nicolas; Lehn, Jean-Marie

2004-09-22

The interaction of an external effector, ZnII ions, with a constitutional dynamic library of fluorescent polyiminofluorenes leads to component exchange, which generates an entity responding by a change in emission to the effector that has induced its formation. The overall coupled system displays a tuning of optical signal, resulting from two synergistic processes: adaptative constitutional reorganization and self-sensing. In broader terms, this work highlights the perspectives opened by constitutional dynamic chemistry toward the design of smart materials, capable of expressing different latent properties in response to environmental conditions.

Vapor Grown Perovskite Solar Cells

NASA Astrophysics Data System (ADS)

Abdussamad Abbas, Hisham

Perovskite solar cells has been the fastest growing solar cell material till date with verified efficiencies of over 22%. Most groups in the world focuses their research on solution based devices that has residual solvent in the material bulk. This work focuses extensively on the fabrication and properties of vapor based perovskite devices that is devoid of solvents. The initial part of my work focuses on the detailed fabrication of high efficiency consistent sequential vapor NIP devices made using P3HT as P-type Type II heterojunction. The sequential vapor devices experiences device anomalies like voltage evolution and IV hysteresis owing to charge trapping in TiO2. Hence, sequential PIN devices were fabricated using doped Type-II heterojunctions that had no device anomalies. The sequential PIN devices has processing restriction, as organic Type-II heterojunction materials cannot withstand high processing temperature, hence limiting device efficiency. Thereby bringing the need of co-evaporation for fabricating high efficiency consistent PIN devices, the approach has no-restriction on substrates and offers stoichiometric control. A comprehensive description of the fabrication, Co-evaporator setup and how to build it is described. The results of Co-evaporated devices clearly show that grain size, stoichiometry and doped transport layers are all critical for eliminating device anomalies and in fabricating high efficiency devices. Finally, Formamidinium based perovskite were fabricated using sequential approach. A thermal degradation study was conducted on Methyl Ammonium Vs. Formamidinium based perovskite films, Formamidinium based perovskites were found to be more stable. Lastly, inorganic films such as CdS and Nickel oxide were developed in this work.

Preparation of Pt Nanocatalyst on Carbon Materials via a Reduction Reaction of a Pt Precursor in a Drying Process.

PubMed

Lee, Jae-Young; Lee, Woo-Kum; Rim, Hyung-Ryul; Joung, Gyu-Bum; Weidner, John W; Lee, Hong-Ki

2016-06-01

Platinum (Pt) nanocatalyst for a proton-exchange membrane fuel cell (PEMFC) was prepared on a carbon black particle or a graphite particle coated with a nafion polymer via a reduction of platinum(II) bis(acetylacetonate) denoted as Pt(acac)2 as a Pt precursor in a drying process. Sublimed Pt(acac)2 adsorbed on the nafion-coated carbon materials was reduced to Pt nanoparticles in a glass reactor at 180 degrees C of N2 atmosphere. The morphology of Pt nanoparticles on carbon materials was observed by scanning electron microscopy (SEM) and the distribution of Pt nanoparticles was done by transmission electron microscopy (TEM). The particle size was estimated by analyzing the TEM image using an image analyzer. It was found that nano-sized Pt particles were deposited on the surface of carbon materials, and the number density and the average particle size increased with increasing reduction time.

Impacts of flocculation on the distribution and diagenesis of iron in boreal estuarine sediments

NASA Astrophysics Data System (ADS)

Jilbert, Tom; Asmala, Eero; Schröder, Christian; Tiihonen, Rosa; Myllykangas, Jukka-Pekka; Virtasalo, Joonas J.; Kotilainen, Aarno; Peltola, Pasi; Ekholm, Päivi; Hietanen, Susanna

2018-03-01

Iron (Fe) plays a key role in sedimentary diagenetic processes in coastal systems, participating in various redox reactions and influencing the burial of organic carbon. Large amounts of Fe enter the marine environment from boreal river catchments associated with dissolved organic matter (DOM) and as colloidal Fe oxyhydroxides, principally ferrihydrite. However, the fate of this Fe pool in estuarine sediments has not been extensively studied. Here we show that flocculation processes along a salinity gradient in an estuary of the northern Baltic Sea efficiently transfer Fe and OM from the dissolved phase into particulate material that accumulates in the sediments. Flocculation of Fe and OM is partially decoupled. This is likely due to the presence of discrete colloidal ferrihydrite in the freshwater Fe pool, which responds differently from DOM to estuarine mixing. Further decoupling of Fe from OM occurs during sedimentation. While we observe a clear decline with distance offshore in the proportion of terrestrial material in the sedimentary particulate organic matter (POM) pool, the distribution of flocculated Fe in sediments is modulated by focusing effects. Labile Fe phases are most abundant at a deep site in the inner basin of the estuary, consistent with input from flocculation and subsequent focusing. The majority of the labile Fe pool is present as Fe (II), including both acid-volatile sulfur (AVS)-bound Fe and unsulfidized phases. The ubiquitous presence of unsulfidized Fe (II) throughout the sediment column suggests Fe (II)-OM complexes derived from reduction of flocculated Fe (III)-OM, while other Fe (II) phases are likely derived from the reduction of flocculated ferrihydrite. Depth-integrated rates of Fe (II) accumulation (AVS-Fe + unsulfidized Fe (II) + pyrite) for the period 1970-2015 are greater in the inner basin of the estuary with respect to a site further offshore, confirming higher rates of Fe reduction in near-shore areas. Mössbauer 57Fe spectroscopy shows that refractory Fe is composed largely of superparamagnetic Fe (III), high-spin Fe (II) in silicates, and, at one station, also oxide minerals derived from past industrial activities. Our results highlight that the cycling of Fe in boreal estuarine environments is complex, and that the partial decoupling of Fe from OM during flocculation and sedimentation is key to understanding the role of Fe in sedimentary diagenetic processes in coastal areas.

Synthesis, structure, and optoelectronic properties of II-IV-V 2 materials

DOE PAGES

Martinez, Aaron D.; Fioretti, Angela N.; Toberer, Eric S.; ...

2017-03-07

II-IV-V 2 materials offer the promise of enhanced functionality in optoelectronic devices due to their rich ternary chemistry. In this review, we consider the potential for new optoelectronic devices based on nitride, phosphide, and arsenide II-IV-V 2 materials. As ternary analogs to the III-V materials, these compounds share many of the attractive features that have made the III-Vs the basis of modern optoelectronic devices (e.g. high mobility, strong optical absorption). Control of cation order parameter in the II-IV-V 2 materials can produce significant changes in optoelectronic properties at fixed chemical composition, including decoupling band gap from lattice parameter. Recent progressmore » has begun to resolve outstanding questions concerning the structure, dopability, and optical properties of the II-IV-V 2 materials. Furthermore, remaining research challenges include growth optimization and integration into heterostructures and devices.« less

Adsorption of heavy metals from aqueous solution by UV-mutant Bacillus subtilis loaded on biochars derived from different stock materials.

PubMed

Wang, Ting; Sun, Hongwen; Ren, Xinhao; Li, Bing; Mao, Hongjun

2018-02-01

Two kinds of biochars, one derived from corn straw (CBC) and one from pig manure (PBC), were used as the carriers of a bacterium (B38) to adsorb heavy metals in solution. CBC exhibited high affinity to Hg(II), while PBC showed large adsorption capacity of Pb(II). After loading with B38, the sorption capacity of the co-sorbents were enhanced for Pb(II), but weakened for Hg(II). In a binary system, the overall adsorption capacity to Hg-Pb (CBC+B38, 136.7mg/g; PBC+B38, 181.3mg/g) on co-sorbents was equal to the sum of the single-component values for Hg(II) and Pb(II). Electrostatic interactions and precipitation are the major mechanisms in the adsorption of Hg(II). In contrast, cation-π interactions and precipitation were involved in the sorption process of Pb(II). Moreover, the sorption sites of Hg(II) and Pb(II) partially overlapped on the biochar surface, but were different on co-sorbents. Hence, the co-sorbents have an advantage over the biochar alone in the removal of heavy metal mixtures. Copyright © 2017 Elsevier Inc. All rights reserved.

Army Sustainment. Volume 43, Issue 4, July-August 2011

DTIC Science & Technology

2011-08-01

ManageMent coMMand. he holdS a B.a. degree in criMinal juStice froM con- cordia college in Michigan and iS level ii certified in PrograM ManageMent and...got there. Think about the entire process, from raw-materials extraction to transformation at a plant or mill, movement of these materials to a manu...facturing plant , assembly of the product’s various components, packaging and further movement to a warehouse or distribution center, delivery to the

Post-synthetic transformation of a Zn(ii) polyhedral coordination network into a new supramolecular isomer of HKUST-1.

PubMed

Chen, Yao; Wojtas, Lukasz; Ma, Shengqian; Zaworotko, Michael J; Zhang, Zhenjie

2017-08-03

A Zn-based porphyrin containing metal-organic material (porphMOM-1) was transformed into a novel Cu-based porphyrin-encapsulating metal-organic material (porph@HKUST-1-β) via a one-pot post-synthetic modification (PSM) process involving both metal ion exchange and linker installation of trimesic acid. HKUST-1-β is the first example of yao topology and is to our knowledge the first supramolecular isomer of the archetypal coordination network HKUST-1.

Nursing Process. Nursing: Basic Needs I. Nursing: Basic Needs II. Nursing through the Life Span. Entry into Professional Nursing. A Basic Course Outline (College Freshmen) for Nursing. A Four Year "2+2" Articulated Curriculum for the Occupation of Nursing.

ERIC Educational Resources Information Center

Maddox, Gaylon; And Others

This course outline provides materials for third-year courses in a "2+2" curriculum for the occupation of registered nurse. It is part of a planned and articulated 4-year curriculum that spans the junior and senior years of high school and the freshman and sophomore years of the postsecondary institution. Introductory materials include:…

[Studies on the extraction process of total saponins from Paris polyphylla Smith].

PubMed

Sun, Zhi-Guo; Zhang, Lin; Li, Ling-Jun; Tian, Jing-Kui

2007-06-01

To optimize the extraction process of total saopnins from Paris polyphylla Smith. The single factor test and orthogonal experiment were used to determine the optimum extraction process. The optimum extraction process was obtained as follows: the plant materials were extracted with 70% ethanol twice, respectively with 10BV for 2 hours and then with 8BV the solvents for 1.5 hours. The yield of total saponins could be up to 4.24% and the total extraction rate of Paris polyphylla I and Paris polyphylla II was 93.28%. The optimum process obtained is steady, reasonable and feasible.

Steric stabilization of nonaqueous silicon slips. I - Control of particle agglomeration and packing. II - Pressure casting of powder compacts

NASA Technical Reports Server (NTRS)

Kerkar, Awdhoot V.; Henderson, Robert J. M.; Feke, Donald L.

1990-01-01

The application of steric stabilization to control particle agglomeration and packing of silicon powder in benzene and trichloroethylene is reported. The results provide useful guidelines for controlling unfavorable particle-particle interactions during nonaqueous processing of silicon-based ceramic materials. The application of steric stabilization to the control and improvement of green processing of nonaqueous silicon slips in pressure consolidation is also demonstrated.

46 CFR 128.210 - Class II vital systems-materials.

Code of Federal Regulations, 2013 CFR

2013-10-01

... ENGINEERING: EQUIPMENT AND SYSTEMS Materials and Pressure Design § 128.210 Class II vital systems—materials... Commanding Officer, Marine Safety Center, if shown to provide a level of safety equivalent to materials in...

46 CFR 128.210 - Class II vital systems-materials.

Code of Federal Regulations, 2011 CFR

2011-10-01

... ENGINEERING: EQUIPMENT AND SYSTEMS Materials and Pressure Design § 128.210 Class II vital systems—materials... Commanding Officer, Marine Safety Center, if shown to provide a level of safety equivalent to materials in...

46 CFR 128.210 - Class II vital systems-materials.

Code of Federal Regulations, 2010 CFR

2010-10-01

... ENGINEERING: EQUIPMENT AND SYSTEMS Materials and Pressure Design § 128.210 Class II vital systems—materials... Commanding Officer, Marine Safety Center, if shown to provide a level of safety equivalent to materials in...

46 CFR 128.210 - Class II vital systems-materials.

Code of Federal Regulations, 2012 CFR

2012-10-01

... ENGINEERING: EQUIPMENT AND SYSTEMS Materials and Pressure Design § 128.210 Class II vital systems—materials... Commanding Officer, Marine Safety Center, if shown to provide a level of safety equivalent to materials in...

46 CFR 128.210 - Class II vital systems-materials.

Code of Federal Regulations, 2014 CFR

2014-10-01

... ENGINEERING: EQUIPMENT AND SYSTEMS Materials and Pressure Design § 128.210 Class II vital systems—materials... Commanding Officer, Marine Safety Center, if shown to provide a level of safety equivalent to materials in...

Continuous powder feeding for pharmaceutical solid dosage form manufacture: a short review.

PubMed

Blackshields, Caroline A; Crean, Abina M

2018-07-01

There has been a noticeable shift from pharmaceutical batch processing towards a more continuous mode of manufacture for solid oral dosage forms. Continuous solid oral dose processes would not be possible in the absence of a highly accurate feeding system. The performance of feeders defines the content of formulations and is therefore a critical operation in continuous manufacturing of solid dosage forms. It was the purpose of this review to review the role of the initial powder feeding step in a continuous manufacturing process. Different feeding mechanisms are discussed with a particular emphasis on screw controlled loss in weight (LIW) feeding. The importance of understanding the physical properties of the raw materials and its impact on the feeding process is reviewed. Prior knowledge of materials provides an initial indication of how the powders will behave through processing and facilitates in the selection of the most suitable (i) feeder (capacity), (ii) feeding mechanism, and (iii) in the case of screw feeder - screw type. The studies identified in this review focus on the impact of material on powder feeding performance.

A Process for Manufacturing Metal-Ceramic Cellular Materials with Designed Mesostructure

NASA Astrophysics Data System (ADS)

Snelling, Dean Andrew, Jr.

The goal of this work is to develop and characterize a manufacturing process that is able to create metal matrix composites with complex cellular geometries. The novel manufacturing method uses two distinct additive manufacturing processes: i) fabrication of patternless molds for cellular metal castings and ii) printing an advanced cellular ceramic for embedding in a metal matrix. However, while the use of AM greatly improves the freedom in the design of MMCs, it is important to identify the constraints imposed by the process and its process relationships. First, the author investigates potential differences in material properties (microstructure, porosity, mechanical strength) of A356 - T6 castings resulting from two different commercially available Binder Jetting media and traditional "no-bake" silica sand. It was determined that they yielded statistically equivalent results in four of the seven tests performed: dendrite arm spacing, porosity, surface roughness, and tensile strength. They differed in sand tensile strength, hardness, and density. Additionally, two critical sources of process constraints on part geometry are examined: (i) depowdering unbound material from intricate casting channels and (ii) metal flow and solidification distances through complex mold geometries. A Taguchi Design of Experiments is used to determine the relationships of important independent variables of each constraint. For depowdering, a minimum cleaning diameter of 3 mm was determined along with an equation relating cleaning distance as a function of channel diameter. Furthermore, for metal flow, choke diameter was found to be significantly significant variable. Finally, the author presents methods to process complex ceramic structure from precursor powders via Binder Jetting AM technology to incorporate into a bonded sand mold and the subsequently casted metal matrix. Through sintering experiments, a sintering temperature of 1375°C was established for the ceramic insert (78% cordierite). Upon printing and sintering the iii ceramic, three point bend tests showed the MMCs had less strength than the matrix material likely due to the relatively high porosity developed in the body. Additionally, it was found that the ceramic metal interface had minimal mechanical interlocking and chemical bonding limiting the strength of the final MMCs.

Australian Biology Test Item Bank, Years 11 and 12. Volume II: Year 12.

ERIC Educational Resources Information Center

Brown, David W., Ed.; Sewell, Jeffrey J., Ed.

This document consists of test items which are applicable to biology courses throughout Australia (irrespective of course materials used); assess key concepts within course statement (for both core and optional studies); assess a wide range of cognitive processes; and are relevant to current biological concepts. These items are arranged under…

49 CFR 173.469 - Tests for special form Class 7 (radioactive) materials.

Code of Federal Regulations, 2010 CFR

2010-10-01

... prescribed in the International Organization for Standardization document ISO 9978-1992(E): “Radiation... not less than 90%. (v) The process in paragraphs (c)(2)(i), (c)(2)(ii), and (c)(2)(iii) of this... International Organization for Standardization document ISO 2919-1980(e), “Sealed Radioactive Sources...

Defense Small Business Innovation Research Program (SBIR). Abstracts of Phase II Awards 1983.

DTIC Science & Technology

1985-01-01

INDEPENDENT EVALUATION OF PROPERTIES. PRELI- MINARY ESTIMATES OF PROCESS COSTS AND COST SAVINGS WILL BE FORMU- LATED. N.J. DAMASKOS , INC. NAVY POST...OFFICE BOX 469 CONCORDVILLE, PA 19331 JOHN L. WALLACE TITLE: A NOVEL LOW-COST INFRARED ABSORBING MATERIAL TOPIC: 100 OFFICE: NAVAIR DAMASKOS , INC. HAS

OP-AMPS on Flexible Substrates with Printable Materials

DTIC Science & Technology

2011-08-10

Zinc Tin Oxide Thin - Film - Transistor Enhancement...II196, 2010. [3] D. Geng, D. H. Kang, and J. Jang, "High-Performance Amorphous Indium-Gallium- Zinc - Oxide Thin - Film Transistor With a Self-Aligned...B., Dodabalapur, A., “Band transport and mobility edge in amorphous solution-processed zinc tin oxide thin - film transistors ”, Applied

Teacher Effectiveness Research. Part II: Special Topics. Bibliographies in Education No. 78.

ERIC Educational Resources Information Center

Gilliss, Geraldine; Moll, Marita

This 723-item bibliography lists materials on teacher effectiveness research published from 1978 to early 1984. Reference to some earlier works of significance is also included. Teacher effectiveness research is here defined to include principally studies conducted in the presage-context-process-product tradition in an attempt to determine…

Recalling Prerequisite Material in a Calculus II Course to Improve Student Success

ERIC Educational Resources Information Center

Mokry, Jeanette

2016-01-01

This article discusses preparation assignments used in a Calculus II course that cover material from prerequisite courses. Prior to learning new material, students work on problems outside of class involving concepts from algebra, trigonometry, and Calculus I. These problems are directly built upon in order to answer Calculus II questions,…

On the Origin of the Type II Spicules: Dynamic Three-dimensional MHD Simulations

NASA Astrophysics Data System (ADS)

Martínez-Sykora, Juan; Hansteen, Viggo; Moreno-Insertis, Fernando

2011-07-01

Recent high temporal and spatial resolution observations of the chromosphere have forced the definition of a new type of spicule, "type II's," that are characterized by rising rapidly, having short lives, and by fading away at the end of their lifetimes. Here, we report on features found in realistic three-dimensional simulations of the outer solar atmosphere that resemble the observed type II spicules. These features evolve naturally from the simulations as a consequence of the magnetohydrodynamical evolution of the model atmosphere. The simulations span from the upper layer of the convection zone to the lower corona and include the emergence of a horizontal magnetic flux. The state-of-art Oslo Staggered Code is used to solve the full MHD equations with non-gray and non-LTE radiative transfer and thermal conduction along the magnetic field lines. We describe in detail the physics involved in a process which we consider a possible candidate for the driver mechanism that produces type II spicules. The modeled spicule is composed of material rapidly ejected from the chromosphere that rises into the corona while being heated. Its source lies in a region with large field gradients and intense electric currents, which lead to a strong Lorentz force that squeezes the chromospheric material, resulting in a vertical pressure gradient that propels the spicule along the magnetic field, as well as Joule heating, which heats the jet material, forcing it to fade.

Real time neutron diffraction and NMR of the Empress II glass-ceramic system.

PubMed

O'Donnell, M D; Hill, R G; Karpukhina, N; Law, R V

2011-10-01

This study reports real time neutron diffraction on the Empress II glass-ceramic system. The commercial glass-ceramics was characterized by real time neutron diffraction, ³¹P and ²⁹Si solid-state MAS-NMR, DSC and XRD. On heating, the as-received glass ceramic contained lithium disilicate (Li₂Si₂O₅), which melted with increasing temperature. This was revealed by neutron diffraction which showed the Bragg peaks for this phase had disappeared by 958°C in agreement with thermal analysis. On cooling lithium metasilicate (Li₂SiO₃) started to form at around 916°C and a minor phase of cristobalite at around 852°C. The unit cell volume of both Li-silicate phases increased linearly with temperature at a rate of +17×10⁻³ ų.°C⁻¹. Room temperature powder X-ray diffraction (XRD) of the material after cooling confirms presence of the lithium metasilicate and cristobalite as the main phases and shows, in addition, small amount of lithium disilicate and orthophosphate. ³¹P MAS-NMR reveals presence of the lithiorthophosphate (Li₃PO₄) before and after heat treatment. The melting of lithium disilicate on heating and crystallisation of lithium metasilicate on cooling agree with endothermic and exotermic features respectively observed by DSC. ²⁹Si MAS-NMR shows presence of lithium disilicate phase in the as-received glass-ceramic, though not in the major proportion, and lithium metasilicate in the material after heat treatment. Both phases have significantly long T₁ relaxation time, especially the lithium metasilicate, therefore, a quantitative analysis of the ²⁹Si MAS-NMR spectra was not attempted. Significance. The findings of the present work demonstrate importance of the commercially designed processing parameters in order to preserve desired characteristics of the material. Processing the Empress II at a rate slower than recommended 60°C min⁻¹ or long isothermal hold at the maximal processing temperature 920°C can cause crystallization of lithium metasilicate and cristobalite instead of lithium disilicate as major phase. Copyright © 2011 Academy of Dental Materials. Published by Elsevier Ltd. All rights reserved.

Highly effective removal of mercury and lead ions from wastewater by mercaptoamine-functionalised silica-coated magnetic nano-adsorbents: Behaviours and mechanisms

NASA Astrophysics Data System (ADS)

Bao, Shuangyou; Li, Kai; Ning, Ping; Peng, Jinhui; Jin, Xu; Tang, Lihong

2017-01-01

A novel hybrid material was fabricated using mercaptoamine-functionalised silica-coated magnetic nanoparticles (MAF-SCMNPs) and was effective in the extraction and recovery of mercury and lead ions from wastewater. The properties of this new magnetic material were explored using various characterisation and analysis methods. Adsorbent amounts, pH levels and initial concentrations were optimised to improve removal efficiency. Additionally, kinetics, thermodynamics and adsorption isotherms were investigated to determine the mechanism by which the fabricated MAF-SCMNPs adsorb heavy metal ions. The results revealed that MAF-SCMNPs were acid-resistant. Sorption likely occurred by chelation through the amine group and ion exchange between heavy metal ions and thiol functional groups on the nanoadsorbent surface. The equilibrium was attained within 120 min, and the adsorption kinetics showed pseudo-second-order (R2 > 0.99). The mercury and lead adsorption isotherms were in agreement with the Freundlich model, displaying maximum adsorption capacities of 355 and 292 mg/g, respectively. The maximum adsorptions took place at pH 5-6 and 6-7 for Hg(II) and Pb(II), respectively. The maximum adsorptions were observed at 10 mg and 12 mg adsorbent quantities for Hg(II) and Pb(II), respectively. The adsorption process was endothermic and spontaneous within the temperature range of 298-318 K. This work demonstrates a unique magnetic nano-adsorbent for the removal of Hg(II) and Pb(II) from wastewater.

Effect of iron and magnesium addition for ethanol production from the conversion of palm oil mill effluent by anaerobic processes

NASA Astrophysics Data System (ADS)

Handajani, M.; Gumilar, A.; Syafila, M.

2018-01-01

Nowadays, crisis of the energy is the main problem in the world. Currently, most the energy resource derived from the fossil material that cannot be refurbished. Ethanol is an alternative fuel that content as a fossil fuels. Wastewater with the high concentration of the organic can be used for the ethanol production to replace foodstuff as a raw material. In this study, palm oil mill effluent (POME) with the concentration of COD is 24,500 mg/L has been used as a substrate. The purpose of this study was to determine the effect of the metal addition in the substrate metabolic pathways. Circulating batch reactor (CBR) is used with the flushing N2 1L/min for 24 hours and continued operates for 72 hours by internal biogas. The additional variation concentration of Fe(II) ion are 0.5; 1.0 and 2.5 mg/L, and Mg(II) are 0.5 and 1.5 mg/L were added by combination. The results showed that the combination of Fe (II) 2.5 mg/L and Mg(II) 1.5 mg/L produced the highest ethanol concentration is 715.8 mg/L and degree of acidification (DA) 0.284-0.357. Another combination of Fe(II) and Mg(II) provide results for the ethanol production 463.7-689.7 mg/L with the rate of ethanol production is 1.09-26.5 mg/L/hour.

40 CFR 52.2635 - Original identification of plan section.

Code of Federal Regulations, 2010 CFR

2010-07-01

... October 30, 1990. (ii) Additional material. (A) November 5, 1990, letter from Douglas Skie, EPA, to...)(ii)(B), (k)(vii) and (o). (ii) Additional material. (A) Letter from Mary A. Throne, Assistant...

40 CFR 52.2635 - Original identification of plan section.

Code of Federal Regulations, 2013 CFR

2013-07-01

... October 30, 1990. (ii) Additional material. (A) November 5, 1990, letter from Douglas Skie, EPA, to...)(ii)(B), (k)(vii) and (o). (ii) Additional material. (A) Letter from Mary A. Throne, Assistant...

40 CFR 52.2635 - Original identification of plan section.

Code of Federal Regulations, 2014 CFR

2014-07-01

... October 30, 1990. (ii) Additional material. (A) November 5, 1990, letter from Douglas Skie, EPA, to...)(ii)(B), (k)(vii) and (o). (ii) Additional material. (A) Letter from Mary A. Throne, Assistant...

40 CFR 52.2635 - Original identification of plan section.

Code of Federal Regulations, 2011 CFR

2011-07-01

... October 30, 1990. (ii) Additional material. (A) November 5, 1990, letter from Douglas Skie, EPA, to...)(ii)(B), (k)(vii) and (o). (ii) Additional material. (A) Letter from Mary A. Throne, Assistant...

40 CFR 52.2635 - Original identification of plan section.

Code of Federal Regulations, 2012 CFR

2012-07-01

... October 30, 1990. (ii) Additional material. (A) November 5, 1990, letter from Douglas Skie, EPA, to...)(ii)(B), (k)(vii) and (o). (ii) Additional material. (A) Letter from Mary A. Throne, Assistant...

Adsorption of Cd(II) from aqueous solutions by rape straw biochar derived from different modification processes.

PubMed

Li, Bing; Yang, Lan; Wang, Chang-Quan; Zhang, Qing-Pei; Liu, Qing-Cheng; Li, Yi-Ding; Xiao, Rui

2017-05-01

In order to deal with cadmium (Cd(II)) pollution, three modified biochar materials: alkaline treatment of biochar (BC-NaOH), KMnO 4 impregnation of biochar (BC-MnO x ) and FeCl 3 magnetic treatment of biochar (BC-FeO x ), were investigated. Nitrogen adsorption-desorption isotherms, Fourier transform infrared spectroscopy (FTIR), Boehm titration, and scanning electron microscopy (SEM) were used to determine the characteristics of adsorbents and explore the main adsorption mechanism. The results show that manganese oxide particles are carried successfully within the biochar, contributing to micropore creation, boosting specific surface area and forming innersphere complexes with oxygen-containing groups, while also increasing the number of oxygen-containing groups. The adsorption sites created by the loaded manganese oxide, rather than specific surface areas, play the most important roles in cadmium adsorption. Batch adsorption experiments demonstrate a Langmuir model fit for Cd(II), and BC-MnO x provided the highest sorption capacity (81.10 mg g -1 ). The sorption kinetics of Cd(II) on adsorbents follows pseudo-second-order kinetics and the adsorption rate of the BC-MnO x material was the highest (14.46 g (mg·h) -1 ). Therefore, biochar modification methods involving KMnO 4 impregnation may provide effective ways of enhancing Cd(II) removal from aqueous solutions. Copyright © 2017 Elsevier Ltd. All rights reserved.

Physical Properties of the MER and Beagle II Landing Sites on Mars

NASA Astrophysics Data System (ADS)

Jakosky, B. M.; Pelkey, S. M.; Mellon, M. T.; Putzig, N.; Martinez-Alonso, S.; Murphy, N.; Hynek, B.

2003-12-01

The ESA Beagle II and the NASA Mars Exploration Rover spacecraft are scheduled to land on the martian surface in December 2003 and January 2004, respectively. Mission operations and success depends on the physical properties of the surfaces on which they land. Surface structural characteristics such as the abundances of loose, unconsolidated fine material, of fine material that has been cemented into a duricrust, and of rocks affect the ability to safely land and to successfully sample and traverse the surface. Also, physical properties affect surface and atmospheric temperatures, which affect lander and rover functionality. We are in the process of analyzing surface temperature information for these sites, derived from MGS TES and Odyssey THEMIS daytime and nighttime measurements. Our approach is to: (i) remap thermal inertia using TES data at ~3-km resolution, to obtain the most complete coverage possible; (ii) interpret physical properties from TES coverage in conjunction with other remote-sensing data sets; (iii) map infrared brightness using daytime and nighttime THEMIS data at 100-m resolution, and do qualitative analysis of physical properties and processes; and (iv) derive thermal inertia from THEMIS nighttime data in conjunction with daytime albedo measurements derived from TES, THEMIS, and MOC observations. In addition, we will use measured temperatures and derived thermal inertia to predict surface temperatures for the periods of the missions.

76 FR 62447 - Importer of Controlled Substances; Notice of Registration

Federal Register 2010, 2011, 2012, 2013, 2014

2011-10-07

... narcotic raw material are not appropriate. With regard to all non-Narcotic Raw Material drugs on this...-phenethyl-4-piperidine (8333)... II Phenylacetone (8501) II Opium, raw (9600) II Poppy Straw Concentrate...

Iron oxide impregnated Morus alba L. fruit peel for biosorption of Co(II): biosorption properties and mechanism.

PubMed

Koduru, Janardhan Reddy; Chang, Yoon-Young; Yang, Jae-Kyu; Kim, Im-Soon

2013-01-01

Biosorption is an ecofriendly wastewater treatment technique with high efficiency and low operating cost involving simple process for the removal of heavy metal ions from aqueous solution. In the present investigation, Morus alba L. fruit peel powder (MAFP) and iron oxide impregnated Morus alba L. fruit peel powder (IO-MAFP) were prepared and used for treating Co(II) contaminated aqueous solutions. Further the materials were characterized by using FTIR and SEM-EDX analysis. From FT-IR analysis it was found that hydroxyl, methoxy, and carbonyl groups are responsible for Co(II) biosorption. The kinetic data obtained for both biosorbents was well fitted with pseudo-second-order kinetic model. The equilibrium data was in tune with the Langmuir and Freundlich isotherm models. The thermodynamic studies were also carried and it was observed that sorption process was endothermic at 298-328 K. These studies demonstrated that both biosorbents were promising, efficient, economic, and biodegradable sorbents.

Lunar-forming impacts: processes and alternatives

PubMed Central

Canup, R. M.

2014-01-01

The formation of a protolunar disc by a giant impact with the early Earth is discussed, focusing on two classes of impacts: (i) canonical impacts, in which a Mars-sized impactor produces a planet–disc system whose angular momentum is comparable to that in the current Earth and Moon, and (ii) high-angular-momentum impacts, which produce a system whose angular momentum is approximately a factor of 2 larger than that in the current Earth and Moon. In (i), the disc originates primarily from impactor-derived material and thus is expected to have an initial composition distinct from that of the Earth's mantle. In (ii), a hotter, more compact initial disc is produced with a silicate composition that can be nearly identical to that of the silicate Earth. Both scenarios require subsequent processes for consistency with the current Earth and Moon: disc–planet compositional equilibration in the case of (i), or large-scale angular momentum loss during capture of the newly formed Moon into the evection resonance with the Sun in the case of (ii). PMID:25114302

Iron Oxide Impregnated Morus alba L. Fruit Peel for Biosorption of Co(II): Biosorption Properties and Mechanism

PubMed Central

Koduru, Janardhan Reddy; Chang, Yoon-Young; Yang, Jae-Kyu; Kim, Im-Soon

2013-01-01

Biosorption is an ecofriendly wastewater treatment technique with high efficiency and low operating cost involving simple process for the removal of heavy metal ions from aqueous solution. In the present investigation, Morus alba L. fruit peel powder (MAFP) and iron oxide impregnated Morus alba L. fruit peel powder (IO-MAFP) were prepared and used for treating Co(II) contaminated aqueous solutions. Further the materials were characterized by using FTIR and SEM-EDX analysis. From FT-IR analysis it was found that hydroxyl, methoxy, and carbonyl groups are responsible for Co(II) biosorption. The kinetic data obtained for both biosorbents was well fitted with pseudo-second-order kinetic model. The equilibrium data was in tune with the Langmuir and Freundlich isotherm models. The thermodynamic studies were also carried and it was observed that sorption process was endothermic at 298–328 K. These studies demonstrated that both biosorbents were promising, efficient, economic, and biodegradable sorbents. PMID:24324384

Nitrogen enriched mesoporous organic polymer anchored copper(II) material: an efficient and reusable catalyst for the synthesis of esters and amides from aromatic systems.

PubMed

Molla, Rostam Ali; Iqubal, Md Asif; Ghosh, Kajari; Kamaluddin; Islam, Sk Manirul

2015-04-14

A new copper-grafted mesoporous poly-melamine-formaldehyde (Cu-mPMF) has been synthesized from melamine and paraformaldehyde in DMSO medium, followed by grafting of Cu(ii) at its surface. Cu-mPMF has been characterized by elemental analysis, powder XRD, HR TEM, FE-SEM, N2 adsorption study, FT-IR, UV-vis DRS, TGA-DTA, EPR spectroscopy, Raman spectroscopy and X-ray photoelectron spectroscopy (XPS). The Cu-grafted mesoporous material showed very good catalytic activity in methyl esterification of benzylic alcohols and amidation of nitriles. Moreover, the catalyst is easily recoverable and can be reused seven times without appreciable loss of catalytic activity in the above reactions. The highly dispersed and strongly bound Cu(ii) sites in the Cu-grafted mesoporous polymer could be responsible for the observed high activities of the Cu-mPMF catalyst. Due to strong binding with the functional groups of the polymer, no evidence of leached copper from the catalyst during the course of reaction emerged, suggesting true heterogeneity in the catalytic process.

Structural changes of oviduct of freshwater shrimp, Macrobrachium nipponense (Decapoda, Palaemonidae), during spawning*

PubMed Central

Lu, Jian-ping; Zhang, Xiao-hui; Yu, Xiao-yun

2006-01-01

The structural change of the oviduct of freshwater shrimp (Macrobrachium nipponense) during spawning was examined by electron microscopy. The oviduct wall structural characteristics seem to be influenced significantly by the spawning process. Before the parturition and ovulation, two types of epithelial cells (types I and II) are found in the epithelium. The free surfaces of type I and type II cells have very dense long microvilli. Under the type I and type II cells, are a relatively thick layer of secreting material and a layer of mostly dead cells. After ovulation, two other types of epithelial cells (types III and IV) are found in the oviduct wall epithelium. The free surface of type III cells only has short microvilli scattered on the surface. The thick layer with secreting material and the dead cell layer disappeared at this stage. In some type III cells, the leaking out of cytoplasm from broken cell membrane led to the death of these type III cells. The transformation of all four types of epithelial cells was in the order: IV→I→II→III. PMID:16365928

Adsorption of mercury from aqueous solutions using palm oil fuel ash as an adsorbent - batch studies

NASA Astrophysics Data System (ADS)

Imla Syafiqah, M. S.; Yussof, H. W.

2018-03-01

Palm oil fuel ash (POFA) is one of the most abundantly produced waste materials. POFA is widely used by the oil palm industry which was collected as ash from the burning of empty fruit bunches fiber (EFB) and palm oil kernel shells (POKS) in the boiler as fuel to generate electricity. Mercury adsorption was conducted in a batch process to study the effects of contact time, initial Hg(II) ion concentration, and temperature. In this study, POFA was prepared and used for the removal of mercury(II) ion from the aqueous phase. The effects of various parameters such as contact time (0- 360 min), temperature (15 – 45 °C) and initial Hg(II) ion concentration (1 – 5 mg/L) for the removal of Hg(II) ion were studied in a batch process. The surface characterization was examined by scanning electron microscopy (SEM) and particle size distribution analysis. From this study, it was found that the highest Hg(II) ion removal was 99.60 % at pH 7, contact time of 4 h, initial Hg(II) ion concentration of 1 mg/L, adsorbent dosage 0.25 g and agitation speed of 100 rpm. The results implied that POFA has the potential as a low-cost and environmental friendly adsorbent for the removal of mercury from aqueous solution.

In vitro chemotaxis and tissue remodeling assays quantitatively characterize foreign body reaction.

PubMed

Jannasch, Maren; Weigel, Tobias; Engelhardt, Lisa; Wiezoreck, Judith; Gaetzner, Sabine; Walles, Heike; Schmitz, Tobias; Hansmann, Jan

2017-01-01

Surgical implantation of a biomaterial triggers foreign-body-induced fibrous encapsulation. Two major mechanisms of this complex physiological process are (I) chemotaxis of fibroblasts from surrounding tissue to the implant region, followed by (II) tissue remodeling. As an alternative to animal studies, we here propose a process-aligned in vitro test platform to investigate the material dependency of fibroblast chemotaxis and tissue remodeling mediated by material-resident macrophages. Embedded in a biomimetic three-dimensional collagen hydrogel, chemotaxis of fibroblasts in the direction of macrophage-material-conditioned cell culture supernatant was analyzed by live cell imaging. A combination of statistical analysis with a complementary parameterized random walk model allowed quantitative and qualitative characterization of the cellular walk process. We thereby identified an increasing macrophage-mediated chemotactic potential ranking of biomaterials from glass over polytetrafluorethylene to titanium. To address long-term effects of bio-material-resident macrophages on fibroblasts in a three-dimensional microenvironment, we further studied tissue remodeling by applying macrophage-material-conditioned medium on fibrous in vitro tissue models. A high correlation of the in vitro tissue model to state of the art in vivo study data was found. Titanium exhibited a significantly lower tissue remodeling capacity compared to polytetrafluorethylene. With this approach, we identified a material dependency of both chemotaxis and tissue remodeling processes, strengthening knowledge on their specific contribution to the foreign body reaction.

Facile and green preparation of novel adsorption materials by combining sol-gel with ion imprinting technology for selective removal of Cu(II) ions from aqueous solution

NASA Astrophysics Data System (ADS)

Ren, Zhongqi; Zhu, Xinyan; Du, Jian; Kong, Delong; Wang, Nian; Wang, Zhuo; Wang, Qi; Liu, Wei; Li, Qunsheng; Zhou, Zhiyong

2018-03-01

A novel green adsorption polymer was prepared by ion imprinted technology in conjunction with sol-gel process under mild conditions for the selective removal of Cu(II) ions from aqueous solution. Effects of preparation conditions on adsorption performance of prepared polymers were studied. The ion-imprinted polymer was prepared using Cu(II) ion as template, N-[3-(2-aminoethylamino) propyl] trimethoxysilane (AAPTMS) as functional monomer and tetraethyl orthosilicate (TEOS) as cross-linker. Water was used as solvent in the whole preparation process. The imprinted and non-imprinted polymers were characterized by Fourier transform infrared spectroscopy (FT-IR), X-ray photoelectron spectroscopy (XPS), scanning electron microscope (SEM), atomic force microscope (AFM), Brunauer, Emmett and Teller (BET) and zeta potential. Three-dimensional network structure was formed and functional monomer was successfully cross-linked into the network structure of polymers. Effects of adsorption conditions on adsorption performance of prepared polymers were studied too. The pH value is of great influence on adsorption behavior. Adsorption by ion-imprinted polymer was fast (adsorption equilibrium was reached within 60 min). The adsorption capacity of Cu(II) ion-imprinted polymer was always larger than that of non-imprinted polymer. Pseudo-second-order kinetics model and Freundlich isotherm model fitted well with adsorption data. The maximum adsorption capacity of Cu(II) ion-imprinted polymer was 39.82 mg·g-1. However, the preparation conditions used in this work are much milder than those reported in literatures. The Cu(II) ion-imprinted polymer showed high selectivity and relative selectivity coefficients for Pb(II), Ni(II), Cd(II) and Co(II). In addition, the prepared ion-imprinted polymer could be reused several times without significant loss of adsorption capacity.

Chromium(II) Metal–Organic Polyhedra as Highly Porous Materials

DOE Office of Scientific and Technical Information (OSTI.GOV)

Park, Jinhee; Perry, Zachary; Chen, Ying-Pin

2017-08-10

Herein we report for the first time the synthesis of Cr(II)-based metal–organic polyhedra (MOPs) and the characterization of their porosities. Unlike the isostructural Cu(II)- or Mo(II)-based MOPs, Cr(II)-based MOPs show unusually high gas uptakes and surface areas. The combination of comparatively robust dichromium paddlewheel units (Cr 2 units), cage symmetries, and packing motifs enable these materials to achieve Brunauer–Emmett–Teller surface areas of up to 1000 m 2/g. Reducing the aggregation of the Cr(II)-based MOPs upon activation makes their pores more accessible than their Cu(II) or Mo(II) counterparts. Further comparisons of surface areas on a molar (m2/mol cage) rather than gravimetricmore » (m 2/g) basis is proposed as a rational method of comparing members of a family of related molecular materials.« less

Ear-like poly (acrylic acid)-activated carbon nanocomposite: A highly efficient adsorbent for removal of Cd(II) from aqueous solutions.

PubMed

Ge, Huacai; Wang, Jincui

2017-02-01

Poly (acrylic acid) modified activated carbon nanocomposite (PAA-AC) was synthesized. The structure and morphology of this nanocomposite were characterized by FTIR, SEM, TEM, XRD and Zeta potential. The adsorption of some heavy metal ions on PAA-AC was studied. The characterization results indicated that PAA-AC was a novel and ear-like nanosheet material with the thickness of about 40 nm and the diameter of about 300 nm. The adsorption results exhibited that the introduction of carboxyl groups into activated carbon evidently increased the uptake for heavy metal ions and the nanocomposite had maximum uptake for Cd(II). Various variables affecting adsorption of PAA-AC for Cd(II) were systematically explored. The maximum capacity and equilibrium time for adsorption of Cd(II) by PAA-AC were 473.2 mg g -1 and 15 min. Moreover, the removal of Cd(II) for real electroplating wastewater by PAA-AC could reach 98.5%. These meant that the removal of Cd(II) by PAA-AC was highly efficient and fast. The sorption kinetics and isotherm fitted well with the pseudo-second-order model and Langmuir model, respectively. The adsorption mainly was a chemical process by chelation. Thermodynamic studies revealed that the adsorption was a spontaneous and endothermic process. The results revealed that PAA-AC could be considered as a potential candidate for Cd(II) removal. Copyright © 2016 Elsevier Ltd. All rights reserved.

Influence of hydroxyapatite granule size, porosity, and crystallinity on tissue reaction in vivo. Part A: synthesis, characterization of the materials, and SEM analysis.

PubMed

Maté Sánchez de Val, José E; Calvo-Guirado, José L; Gómez-Moreno, Gerardo; Pérez-Albacete Martínez, Carlos; Mazón, Patricia; De Aza, Piedad N

2016-11-01

The aim of this study was the synthesis and analysis of the tissue reaction to three different Hydroxyapatite (HA)-based bone substitute materials differing only in granule size, porosity, and crystallinity through an animal experimental model at 60 days. Three different HA-based biomaterials were synthesized and characterized by X-ray diffraction, SEM, and EDS analysis, the resultant product was ground in three particle sizes: Group I (2000-4000 μm), Group II (1000-2000 μm), and Group III (600-1000 μm). Critical size defects were created in both tibias of 15 rabbits. Four defects per rabbit for a total of 60 defects were grafted with the synthesized materials as follows: Group I (15 defects), Group II (15 defects), Group III (15 defects), and empty (15 defects control). After animals sacrifice at 60 days samples were obtained and processed for SEM and EDS evaluation of Ca/P ratios, elemental mapping was performed to determine the chemical degradation process and changes to medullary composition in all the four study groups. The tendency for the density was to increase with the increasing annealing temperature; in this way it was possible to observe that the sample that shows highest crystallinity and crystal size corresponding to that of group I. The SEM morphological examination showed that group III implant showed numerous resorption regions, group II implant presented an average resorption rate of all the implants. The group I displayed smoother surface features, in comparison with the other two implants. The data from this study show that changing the size, porosity, and crystallinity of one HA-based bone substitute material can influence the integration of the biomaterials within the implantation site and the new bone formation. © 2015 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

77 FR 31388 - Importer of Controlled Substances; Notice of Application; Noramco, Inc.

Federal Register 2010, 2011, 2012, 2013, 2014

2012-05-25

... material are not appropriate. 72 FR 3417 (2007). In regard to the non-narcotic raw material, any bulk... following basic classes of controlled substances: Drug Schedule Phenylacetone (8501) II Opium, raw (9600) II Poppy Straw Concentrate (9670) II Tapentadol (9780) II The company plans to import the raw Opium (9600...

Dental ceramics: a review of new materials and processing methods.

PubMed

Silva, Lucas Hian da; Lima, Erick de; Miranda, Ranulfo Benedito de Paula; Favero, Stéphanie Soares; Lohbauer, Ulrich; Cesar, Paulo Francisco

2017-08-28

The evolution of computerized systems for the production of dental restorations associated to the development of novel microstructures for ceramic materials has caused an important change in the clinical workflow for dentists and technicians, as well as in the treatment options offered to patients. New microstructures have also been developed by the industry in order to offer ceramic and composite materials with optimized properties, i.e., good mechanical properties, appropriate wear behavior and acceptable aesthetic characteristics. The objective of this literature review is to discuss the main advantages and disadvantages of the new ceramic systems and processing methods. The manuscript is divided in five parts: I) monolithic zirconia restorations; II) multilayered dental prostheses; III) new glass-ceramics; IV) polymer infiltrated ceramics; and V) novel processing technologies. Dental ceramics and processing technologies have evolved significantly in the past ten years, with most of the evolution being related to new microstructures and CAD-CAM methods. In addition, a trend towards the use of monolithic restorations has changed the way clinicians produce all-ceramic dental prostheses, since the more aesthetic multilayered restorations unfortunately are more prone to chipping or delamination. Composite materials processed via CAD-CAM have become an interesting option, as they have intermediate properties between ceramics and polymers and are more easily milled and polished.

Fate of nuclear material during subsequent steps of the kinetin-induced PCD in apical parts of Vicia faba ssp. minor seedling roots.

PubMed

Kaźmierczak, Andrzej; Soboska, Kamila

2018-07-01

In animals during apoptosis, the best examined type of programmed cell death (PCD), three main phases are distinguished: (i) specification (signaling), (ii) killing and (iii) execution one. It has bean postulated that plant PCD also involves three subsequent phases: (i) transmission of death signals to cells (signaling), (ii) initiation of killing processes and (iii) destruction of cells. One of the most important hallmarks of animal and plant PCD are those regarding nucleus, not thoroughly studied in plants so far. To study kinetin-induced PCD (Kin-PCD) in the context of nuclear material faith, 2-cm apical parts of Vicia faba ssp. minor seedling roots were used. Applied assays involving spectrophotometry, transmission electron microscopy, fluorescence and white light microscopy allowed to examine metabolic and cytomorphologic hallmarks such as changes in DNA content, ssDNA formation and activity of acidic and basic nucleases (DNases and RNases) as well as malformations and fragmentation of nucleoli and nuclei. The obtained results concerning the PCD hallmarks and influence of ZnSO 4 on Kin-PCD allowed us to confirmed presence of specification/signaling, killing and execution/degradation phases of the process and broaden the knowledge about processes affecting nuclei during PCD. Copyright © 2018 Elsevier Ltd. All rights reserved.

Materials, devices, techniques, and applications for Z-plane focal plane array technology II; Proceedings of the Meeting, San Diego, CA, July 12, 13, 1990

NASA Astrophysics Data System (ADS)

Carson, John C.

1990-11-01

Various papers on materials, devices, techniques, and applications for X-plane focal plane array technology are presented. Individual topics addressed include: application of Z-plane technology to the remote sensing of the earth from GEO, applications of smart neuromorphic focal planes, image-processing of Z-plane technology, neural network Z-plane implementation with very high interconnection rates, using a small IR surveillance satellite for tactical applications, establishing requirements for homing applications, Z-plane technology. Also discussed are: on-array spike suppression signal processing, algorithms for on-focal-plane gamma circumvention and time-delay integration, current HYMOSS Z-technology, packaging of electrons for on- and off-FPA signal processing, space/performance qualification of tape automated bonded devices, automation in tape automated bonding, high-speed/high-volume radiometric testing of Z-technology focal planes, 128-layer HYMOSS-module fabrication issues, automation of IRFPA production processes.

46 CFR 160.132-13 - Approval inspections and tests for prototype davits.

Code of Federal Regulations, 2012 CFR

2012-10-01

... reviewed under § 160.132-9 of this subpart; and (C) When welding is part of the construction process, is constructed by the welding procedure and materials as per the plans reviewed under § 160.132-9 of this subpart and the welders are appropriately qualified; (ii) Assuring that the quality-assurance program of the...

46 CFR 160.115-13 - Approval inspections and tests for prototype winches.

Code of Federal Regulations, 2012 CFR

2012-10-01

... reviewed under § 160.115-9 of this subpart; and (C) When welding is part of the construction process, is constructed by the welding procedure and materials as per the plans reviewed under § 160.115-9 of this subpart and the welders are appropriately qualified; (ii) Assuring that the quality-assurance program of the...

46 CFR 160.115-13 - Approval inspections and tests for prototype winches.

Code of Federal Regulations, 2014 CFR

2014-10-01

... reviewed under § 160.115-9 of this subpart; and (C) When welding is part of the construction process, is constructed by the welding procedure and materials as per the plans reviewed under § 160.115-9 of this subpart and the welders are appropriately qualified; (ii) Assuring that the quality-assurance program of the...

46 CFR 160.115-13 - Approval inspections and tests for prototype winches.

Code of Federal Regulations, 2013 CFR

2013-10-01

... reviewed under § 160.115-9 of this subpart; and (C) When welding is part of the construction process, is constructed by the welding procedure and materials as per the plans reviewed under § 160.115-9 of this subpart and the welders are appropriately qualified; (ii) Assuring that the quality-assurance program of the...

46 CFR 160.132-13 - Approval inspections and tests for prototype davits.

Code of Federal Regulations, 2013 CFR

2013-10-01

... reviewed under § 160.132-9 of this subpart; and (C) When welding is part of the construction process, is constructed by the welding procedure and materials as per the plans reviewed under § 160.132-9 of this subpart and the welders are appropriately qualified; (ii) Assuring that the quality-assurance program of the...

46 CFR 160.132-13 - Approval inspections and tests for prototype davits.

Code of Federal Regulations, 2014 CFR

2014-10-01

... reviewed under § 160.132-9 of this subpart; and (C) When welding is part of the construction process, is constructed by the welding procedure and materials as per the plans reviewed under § 160.132-9 of this subpart and the welders are appropriately qualified; (ii) Assuring that the quality-assurance program of the...

16 CFR 303.33 - Country where textile fiber products are processed or manufactured.

Code of Federal Regulations, 2013 CFR

2013-01-01

... [Foreign Country]”. (ii) When the U.S. Customs Service requires an origin label on the unfinished product... manufacturer needs to consider the origin of only those materials that are covered under the Act and that are... species of product. Variant spellings which clearly indicate the English name of the country, such as...

16 CFR 303.33 - Country where textile fiber products are processed or manufactured.

Code of Federal Regulations, 2014 CFR

2014-01-01

... [Foreign Country]”. (ii) When the U.S. Customs Service requires an origin label on the unfinished product... manufacturer needs to consider the origin of only those materials that are covered under the Act and that are... species of product. Variant spellings which clearly indicate the English name of the country, such as...

16 CFR 303.33 - Country where textile fiber products are processed or manufactured.

Code of Federal Regulations, 2012 CFR

2012-01-01

... [Foreign Country]”. (ii) When the U.S. Customs Service requires an origin label on the unfinished product... manufacturer needs to consider the origin of only those materials that are covered under the Act and that are... species of product. Variant spellings which clearly indicate the English name of the country, such as...

40 CFR 261.2 - Definition of solid waste.

Code of Federal Regulations, 2010 CFR

2010-07-01

... reclaimed, it is not a spent lead acid battery (see § 266.80 and § 273.2), it does not meet the listing... are solid wastes if they are recycled—or accumulated, stored, or treated before recycling—as specified... are not used or reused during the recycling process; and (ii) The material may pose a substantial...

40 CFR 261.2 - Definition of solid waste.

Code of Federal Regulations, 2011 CFR

2011-07-01

... reclaimed, it is not a spent lead acid battery (see § 266.80 and § 273.2), it does not meet the listing... are solid wastes if they are recycled—or accumulated, stored, or treated before recycling—as specified... are not used or reused during the recycling process; and (ii) The material may pose a substantial...

40 CFR 261.2 - Definition of solid waste.

Code of Federal Regulations, 2014 CFR

2014-07-01

... reclaimed, it is not a spent lead acid battery (see § 266.80 and § 273.2), it does not meet the listing... are solid wastes if they are recycled—or accumulated, stored, or treated before recycling—as specified... are not used or reused during the recycling process; and (ii) The material may pose a substantial...

40 CFR 261.2 - Definition of solid waste.

Code of Federal Regulations, 2013 CFR

2013-07-01

... reclaimed, it is not a spent lead acid battery (see § 266.80 and § 273.2), it does not meet the listing... are solid wastes if they are recycled—or accumulated, stored, or treated before recycling—as specified... are not used or reused during the recycling process; and (ii) The material may pose a substantial...

40 CFR 261.2 - Definition of solid waste.

Code of Federal Regulations, 2012 CFR

2012-07-01

... reclaimed, it is not a spent lead acid battery (see § 266.80 and § 273.2), it does not meet the listing... are solid wastes if they are recycled—or accumulated, stored, or treated before recycling—as specified... are not used or reused during the recycling process; and (ii) The material may pose a substantial...

Effects of Meaningfulness and Context on Information Processing in Third-Graders.

ERIC Educational Resources Information Center

Montgomery, Theresa; Richman, Shanna

The effects of meaningfulness of the stimulus materials and the presence or absence of contextual cues on problem-solving behavior were investigated. Third-graders (N=80) were randomly assigned to one of four conditions and their performance in a series of discrimination problems was observed. Subjects in Conditions I and II responded to stimuli…

7 CFR 1.640 - What are the requirements for prehearing conferences?

Code of Federal Regulations, 2010 CFR

2010-01-01

... and the schedule of remaining steps in the hearing process. (e) Failure to attend. Unless the ALJ... prehearing conference with the parties at the time specified in the docketing notice under § 1.630, on or... exclude issues that do not qualify for review as factual, material, and disputed; (ii) To consider the...

Upward Mobility Programs in the Service Sector for Disadvantaged and Dislocated Workers. Volume II: Technical Appendices.

ERIC Educational Resources Information Center

Tao, Fumiyo; And Others

This volume contains technical and supporting materials that supplement Volume I, which describes upward mobility programs for disadvantaged and dislocated workers in the service sector. Appendix A is a detailed description of the project methodology, including data collection methods and information on data compilation, processing, and analysis.…

Synthesis, characterization, photoluminescence, and electrochemical studies of novel mononuclear Cu(II) and Zn(II) complexes with the 1-benzylimidazolium ligand

NASA Astrophysics Data System (ADS)

Bibi, Sherino; Mohammad, Sharifah; Manan, Ninie Suhana Abdul; Ahmad, Jimmy; Kamboh, Muhammad Afzal; Khor, Sook Mei; Yamin, Bohari M.; Abdul Halim, Siti Nadiah

2017-08-01

Two new mononuclear coordination complexes [Cu(bim)4Cl2]ṡ2H2O (1) and [Zn(bim)2Cl2] (2) containing the 1-benzylimidazole (bim) ligand were successfully synthesized. Both complexes were characterized by IR, UV-vis, and fluorescence spectroscopies, single crystal and powder X-ray diffraction measurements, and thermogravimetric analysis. Self-assembly during the recrystallization process resulted in the formation of octahedral and tetrahedral Cu(II) and Zn(II) complexes, respectively. The single crystals obtained are representative of the bulk material, as shown by the powder X-ray diffraction patterns. Cyclic voltammetry measurements showed that complex 1 undergoes a quasi-reversible redox reaction, while complex 2 undergoes reduction alone, and no oxidation peak was observed; this is due to the stability of the reduced form of complex 2.

The identification of group II inclusions in carbonaceous chondrites by electron probe microanalysis of perovskite

NASA Technical Reports Server (NTRS)

Kornacki, A. S.; Wood, J. A.

1985-01-01

The technique developed by Kornacki (1984) for identifying group II Ca/Al-rich inclusions in carbonaceous chondrites by electron-microprobe analysis of the ZrO2 or Y2O3 content of their perovskite component is demonstrated using material from 20 Allende inclusions. The results are presented in tables and graphs and compared with findings obtained by other procedures. Group II inclusions are found to have perovskites generally containing less than 0.10 wt pct ZrO2 and/or Y2O3 (average of several grains), while those of groups I, III, V, and VI have more than 0.25 wt pct ZrO2. Analysis of data on eight Allende Ca/Al-rich inclusions shows that 75 percent of the fine-grained inclusions belong to group II. The implications of these findings for fractionation processes in the primitive solar nebula are indicated.

Disposition of fuel elements from the Aberdeen and Sandia pulse reactor (SPR-II) assemblies

DOE Office of Scientific and Technical Information (OSTI.GOV)

Mckerley, Bill; Bustamante, Jacqueline M; Costa, David A

2010-01-01

We describe the disposition of fuel from the Aberdeen (APR) and the Sandia Pulse Reactors (SPR-II) which were used to provide intense neutron bursts for radiation effects testing. The enriched Uranium - 10% Molybdenum fuel from these reactors was shipped to the Los Alamos National Laboratory (LANL) for size reduction prior to shipment to the Savannah River Site (SRS) for final disposition in the H Canyon facility. The Shipper/Receiver Agreements (SRA), intra-DOE interfaces, criticality safety evaluations, safety and quality requirements and key materials management issues required for the successful completion of this project will be presented. This work is inmore » support of the DOE Consolidation and Disposition program. Sandia National Laboratories (SNL) has operated pulse nuclear reactor research facilities for the Department of Energy since 1961. The Sandia Pulse Reactor (SPR-II) was a bare metal Godiva-type reactor. The reactor facilities have been used for research and development of nuclear and non-nuclear weapon systems, advanced nuclear reactors, reactor safety, simulation sources and energy related programs. The SPR-II was a fast burst reactor, designed and constructed by SNL that became operational in 1967. The SPR-ll core was a solid-metal fuel enriched to 93% {sup 235}U. The uranium was alloyed with 10 weight percent molybdenum to ensure the phase stabilization of the fuel. The core consisted of six fuel plates divided into two assemblies of three plates each. Figure 1 shows a cutaway diagram of the SPR-II Reactor with its decoupling shroud. NNSA charged Sandia with removing its category 1 and 2 special nuclear material by the end of 2008. The main impetus for this activity was based on NNSA Administrator Tom D'Agostino's six focus areas to reenergize NNSA's nuclear material consolidation and disposition efforts. For example, the removal of SPR-II from SNL to DAF was part of this undertaking. This project was in support of NNSA's efforts to consolidate the locations of special nuclear material (SNM) to reduce the cost of securing many SNM facilities. The removal of SPR-II from SNL was a significant accomplishment in SNL's de-inventory efforts and played a key role in reducing the number of locations requiring the expensive security measures required for category 1 and 2 SNM facilities. A similar pulse reactor was fabricated at the Y-12 National Security Complex beginning in the late 1960's. This Aberdeen Pulse Reactor (APR) was operated at the Army Pulse Radiation Facility (APRF) located at the Aberdeen Test Center (ATC) in Maryland. When the APRF was shut down in 2003, a portion of the DOE-owned Special Nuclear Material (SNM) was shipped to an interim facility for storage. Subsequently, the DOE determined that the material from both the SPR-II and the APR would be processed in the H-Canyon at the Savannah River Site (SRS). Because of the SRS receipt requirements some of the material was sent to the Los Alamos National Laboratory (LANL) for size-reduction prior to shipment to the SRS for final disposition.« less

Cell migration and antigen capture are antagonistic processes coupled by myosin II in dendritic cells

PubMed Central

Chabaud, Mélanie; Heuzé, Mélina L.; Bretou, Marine; Vargas, Pablo; Maiuri, Paolo; Solanes, Paola; Maurin, Mathieu; Terriac, Emmanuel; Le Berre, Maël; Lankar, Danielle; Piolot, Tristan; Adelstein, Robert S.; Zhang, Yingfan; Sixt, Michael; Jacobelli, Jordan; Bénichou, Olivier; Voituriez, Raphaël; Piel, Matthieu; Lennon-Duménil, Ana-Maria

2015-01-01

The immune response relies on the migration of leukocytes and on their ability to stop in precise anatomical locations to fulfil their task. How leukocyte migration and function are coordinated is unknown. Here we show that in immature dendritic cells, which patrol their environment by engulfing extracellular material, cell migration and antigen capture are antagonistic. This antagonism results from transient enrichment of myosin IIA at the cell front, which disrupts the back-to-front gradient of the motor protein, slowing down locomotion but promoting antigen capture. We further highlight that myosin IIA enrichment at the cell front requires the MHC class II-associated invariant chain (Ii). Thus, by controlling myosin IIA localization, Ii imposes on dendritic cells an intermittent antigen capture behaviour that might facilitate environment patrolling. We propose that the requirement for myosin II in both cell migration and specific cell functions may provide a general mechanism for their coordination in time and space. PMID:26109323

Effects of marine actinomycete on the removal of a toxicity alga Phaeocystis globose in eutrophication waters.

PubMed

Zhang, Huajun; Zhang, Su; Peng, Yun; Li, Yi; Chen, Zhangran; Xu, Hong; Yu, Zhiming; Zheng, Wei; Zheng, Tianling

2015-01-01

Phaeocystis globosa blooms in eutrophication waters can cause severely damage in marine ecosystem and consequently influence human activities. This study investigated the effect and role of an algicidal actinomycete (Streptomyces sp. JS01) on the elimination process of P. globosa. JS01 supernatant could alter algal cell membrane permeability in 4 h when analyzed with flow cytometry. Reactive oxygen species (ROS) levels were 7.2 times higher than that at 0 h following exposure to JS01 supernatant for 8 h, which indicated that algal cells suffered from oxidative damage. The Fv/Fm value which could reflect photosystem II (PS II) electron flow status also decreased. Real-time PCR showed that the expression of the photosynthesis related genes psbA and rbcS were suppressed by JS01 supernatant, which might induce damage to PS II. Our results demonstrated that JS01 supernatant can change algal membrane permeability in a short time and then affect photosynthesis process, which might block the PS II electron transport chain to produce excessive ROS. This experiment demonstrated that Streptomyces sp. JS01 could eliminate harmful algae in marine waters efficiently and may be function as a harmful algal bloom controller material.

Effects of marine actinomycete on the removal of a toxicity alga Phaeocystis globose in eutrophication waters

PubMed Central

Zhang, Huajun; Zhang, Su; Peng, Yun; Li, Yi; Chen, Zhangran; Xu, Hong; Yu, Zhiming; Zheng, Wei; Zheng, Tianling

2015-01-01

Phaeocystis globosa blooms in eutrophication waters can cause severely damage in marine ecosystem and consequently influence human activities. This study investigated the effect and role of an algicidal actinomycete (Streptomyces sp. JS01) on the elimination process of P. globosa. JS01 supernatant could alter algal cell membrane permeability in 4 h when analyzed with flow cytometry. Reactive oxygen species (ROS) levels were 7.2 times higher than that at 0 h following exposure to JS01 supernatant for 8 h, which indicated that algal cells suffered from oxidative damage. The Fv/Fm value which could reflect photosystem II (PS II) electron flow status also decreased. Real-time PCR showed that the expression of the photosynthesis related genes psbA and rbcS were suppressed by JS01 supernatant, which might induce damage to PS II. Our results demonstrated that JS01 supernatant can change algal membrane permeability in a short time and then affect photosynthesis process, which might block the PS II electron transport chain to produce excessive ROS. This experiment demonstrated that Streptomyces sp. JS01 could eliminate harmful algae in marine waters efficiently and may be function as a harmful algal bloom controller material. PMID:26042109

Fuel-Flexible Gasification-Combustion Technology for Production of H2 and Sequestration-Ready CO2

DOE Office of Scientific and Technical Information (OSTI.GOV)

Parag Kulkarni; Jie Guan; Raul Subia

In the near future, the nation will continue to rely on fossil fuels for electricity, transportation, and chemicals. It is necessary to improve both the process efficiency and environmental impact of fossil fuel utilization including greenhouse gas management. GE Global Research (GEGR) investigated an innovative fuel-flexible Unmixed Fuel Processor (UFP) technology with potential to produce H{sub 2}, power, and sequestration-ready CO{sub 2} from coal and other solid fuels. The UFP technology offers the long-term potential for reduced cost, increased process efficiency relative to conventional gasification and combustion systems, and near-zero pollutant emissions. GE was awarded a contract from U.S. DOEmore » NETL to investigate and develop the UFP technology. Work started on the Phase I program in October 2000 and on the Phase II effort in April 2005. In the UFP technology, coal, water and air are simultaneously converted into (1) hydrogen rich stream that can be utilized in fuel cells or turbines, (2) CO{sub 2} rich stream for sequestration, and (3) high temperature/pressure vitiated air stream to produce electricity in a gas turbine expander. The process produces near-zero emissions with an estimated efficiency higher than Integrated Gasification Combined Cycle (IGCC) process with conventional CO{sub 2} separation. The Phase I R&D program established the chemical feasibility of the major reactions of the integrated UFP technology through lab-, bench- and pilot-scale testing. A risk analysis session was carried out at the end of Phase I effort to identify the major risks in the UFP technology and a plan was developed to mitigate these risks in the Phase II of the program. The Phase II effort focused on three high-risk areas: economics, lifetime of solids used in the UFP process, and product gas quality for turbines (or the impact of impurities in the coal on the overall system). The economic analysis included estimating the capital cost as well as the costs of hydrogen and electricity for a full-scale UFP plant. These costs were benchmarked with IGCC polygen plants with similar level of CO{sub 2} capture. Based on the promising economic analysis comparison results (performed with the help from Worley Parsons), GE recommended a 'Go' decision in April 2006 to continue the experimental investigation of the UFP technology to address the remaining risks i.e. solids lifetime and the impact of impurities in the coal on overall system. Solids attrition and lifetime risk was addressed via bench-scale experiments that monitor solids performance over time and by assessing materials interactions at operating conditions. The product gas under the third reactor (high-temperature vitiated air) operating conditions was evaluated to assess the concentration of particulates, pollutants and other impurities relative to the specifications required for gas turbine feed streams. During this investigation, agglomeration of solids used in the UFP process was identified as a serious risk that impacts the lifetime of the solids and in turn feasibility of the UFP technology. The main causes of the solids agglomeration were the combination of oxygen transfer material (OTM) reduction at temperatures {approx}1000 C and interaction between OTM and CO{sub 2} absorbing material (CAM) at high operating temperatures (>1200 C). At the end of phase II, in March 2008, GEGR recommended a 'No-go' decision for taking the UFP technology to the next level of development, i.e. development of a 3-5 MW prototype system, at this time. GEGR further recommended focused materials development research programs on improving the performance and lifetime of solids materials used in UFP or chemical looping technologies. The scale-up activities would be recommended only after mitigating the risks involved with the agglomeration and overall lifetime of the solids. This is the final report for the phase II of the DOE-funded Vision 21 program entitled 'Fuel-Flexible Gasification-Combustion Technology for Production of H{sub 2} and Sequestration-Ready CO{sub 2}' (DOE Award No. DE-FC26-00NT40974). The report focuses on the major accomplishments and lessons learned in analyzing the risks of the novel UFP technology during Phase II of the DOE program.« less

The Rise of Highly Efficient and Stable Perovskite Solar Cells.

PubMed

Grätzel, Michael

2017-03-21

Recently, metal halide perovskite solar cells (PSCs) of the general formular ABX 3 where A is a monovalent cation, that is, methylammonium (MA) CH 3 NH 3 +• , formamidinium CH 2 (NH 2 ) 2 + , Cs + , or Rb + , B stands for Pb(II) or Sn(II), and X for iodide or bromide have achieved solar to electric power conversion efficiencies (PCEs) above 22%, exceeding the efficiency of the present market leader polycrystalline silicon while using 1000 times less light harvesting material and simple solution processing for their fabrication. The top performing devices all employ formulations containing a mixture of up to four A cations and iodide as well as a small fraction of bromide as anion, whose emergence will be described in this Commentary. Apart from leading the current PV efficiency race, these new perovskite materials exhibit intense electroluminescence and an extraordinarily high stability under heat and light stress.

Effects of Chemistry and Processing on the Fracture Related Properties of P/M Alloy CT91.

DTIC Science & Technology

1985-08-01

Paris- Erdogan equation [151]. da/dN = AAk’ (8) where A and m are material constants. Stage II is generally characterized by a continuum mechanism...1. Paris and Erdogan [151] da/dN = CAKm (15) where da/dN = crack growth per cycle C, m = material constants AK = stress intensity parameter range The...extensometer was placed on two strips of masking tape to avoid notching the specimen and was carefully attached by two springs. A plastic bag was placed

Portable Device Analyzes Rocks and Minerals

NASA Technical Reports Server (NTRS)

2008-01-01

inXitu Inc., of Mountain View, California, entered into a Phase II SBIR contract with Ames Research Center to develop technologies for the next generation of scientific instruments for materials analysis. The work resulted in a sample handling system that could find a wide range of applications in research and industrial laboratories as a means to load powdered samples for analysis or process control. Potential industries include chemical, cement, inks, pharmaceutical, ceramics, and forensics. Additional applications include characterizing materials that cannot be ground to a fine size, such as explosives and research pharmaceuticals.

US-UK Collaboration on Fossil Energy Advanced Materials: Task 1—Steam Oxidation

DOE Office of Scientific and Technical Information (OSTI.GOV)

Holcomb, Gordon R.; Tylczak, Joseph; Carney, Casey

This presentation goes over the following from the US-UK collaboration on Fossil Energy Advanced Materials: Task 1, Steam Oxidation: US-led or co-led deliverables, Phase II products (US), 2011-present, Phase III products, Phase III Plan, an explanation of sCO 2 compared with sH 2O, an explanation of Ni-base Alloys, an explanation of 300 Series (18Cr-8Ni)/E-Brite, an explanation of the typical Microchannel HX Fabrication process, and an explanation of diffusion bonded Ni-base superalloys.

Mössbauer spectroscopy on Mars: goethite in the Columbia Hills at Gusev crater

NASA Astrophysics Data System (ADS)

Klingelhöfer, G.; Degrave, E.; Morris, R. V.; van Alboom, A.; de Resende, V. G.; de Souza, P. A.; Rodionov, D.; Schröder, C.; Ming, D. W.; Yen, A.

2005-11-01

In January 2004 the USA space agency NASA landed two rovers on the surface of Mars, both carrying the Mainz Mössbauer spectrometer MIMOS II. The instrument on the Mars-Exploration-Rover (MER) Spirit analyzed soils and rocks on the plains and in the Columbia Hills of Gusev crater landing site on Mars. The surface material in the plains have an olivine basaltic signature [1, 5] suggesting physical rather than chemical weathering processes present in the plains. The Mössbauer signature for the Columbia Hills surface material is very different ranging from nearly unaltered material to highly altered material. Some of the rocks, in particular a rock named Clovis, contain a significant amount of the Fe oxyhydroxide goethite, α-FeOOH, which is mineralogical evidence for aqueous processes because it is formed only under aqueous conditions. In this paper we describe the analysis of these data using hyperfine field distributions (HFD) and discuss the results in comparison to terrestrial analogues.

Surface Modifications of Materials by Electrochemical Methods to Improve the Properties for Industrial and Medical Applications

NASA Astrophysics Data System (ADS)

Benea, Lidia

2018-06-01

There are two applied electrochemical methods in our group in order to obtain advanced functional surfaces on materials: (i) direct electrochemical synthesis by electro-codeposition process and (ii) anodization of materials to form nanoporous oxide layers followed by electrodeposition of hydroxyapatite or other bioactive molecules and compounds into porous film. Electrodeposition is a process of low energy consumption, and therefore very convenient for the surface modification of various types of materials. Electrodeposition is a powerful method compared with other methods, which led her to be adopted and spread rapidly in nanotechnology to obtain nanostructured layers and films. Nanoporous thin oxide layers on titanum alloys as support for hydroxyapatite or other biomolecules electrodeposition in view of biomedical applications could be obtained by electrochemical methods. For surface modification of titanium or titanium alloys to improve the biocompatibility or osseointegration, the two steps must be fulfilled; the first is controlled growth of oxide layer followed by second being biomolecule electrodeposition into nanoporous formed titanium oxide layer.

Synthesis and adsorption of silica gel modified 3-aminopropyltriethoxysilane (APTS) from corn cobs against Cu(II) in water

NASA Astrophysics Data System (ADS)

Purwanto, Agung; Yusmaniar, Ferdiani, Fatmawati; Damayanti, Rachma

2017-03-01

Silica gel modified APTS was synthesized from silica gel which was obtained from corn cobs via sol-gel process. Silica gel was synthesized from corn cobs and then chemically modified with silane coupling agent which has an amine group (NH2). This process resulting modified silica gel 3-aminopropyltriethoxysilane (APTS). Characterization of silica gel modified APTS by SEM-EDX showed that the size of the particles of silica gel modified APTS was 20µm with mass percentage of individual elements were nitrogen (N) 15.56%, silicon (Si) 50.69% and oxygen (O) 33.75%. In addition, silica gel modified APTS also showed absorption bands of functional groups silanol (Si-OH), siloxane (Si-O-Si), and an aliphatic chain (-CH2-), as well as amine (NH2) from FTIR spectra. Based on the characterization of XRD, silica gel 2θ of 21.094° and 21.32° respectively. It indicated that both material were amorphous. Determination of optimum pH and contact time on adsorption of silica gel 3-aminopropyltriethoxysilane (APTS) against Cu(II). The optimum pH and contact time was measured by using AAS. Optimum pH of adsorption silica gel modified APTS against metal Cu(II) could be obtained at pH 6 while optimum contact time was at 30 minutes, with the process of adsorption metal Cu(II) occured based on the model Freundlich isotherm.

49 CFR 178.46 - Specification 3AL seamless aluminum cylinders.

Code of Federal Regulations, 2010 CFR

2010-10-01

... material; or (ii) Obtaining a certified chemical analysis from the material or cylinder manufacturer for each melt, or cast of material; or (iii) Obtaining a certified check analysis on one cylinder out of...) Selecting the samples for check analyses performed by other than the material producer; (ii) Verifying that...

Validation and refinement of mixture volumetric material properties identified in superpave monitoring project II : phase II.

DOT National Transportation Integrated Search

2015-02-01

This study was initiated to validate and refine mixture volumetric material properties identified in the : Superpave Monitoring Project II. It has been found that differences in performance are primarily controlled : by differences in gradation and r...

Identification of a thermo-elasto-viscoplastic behavior law for the simulation of thermoforming of high impact polystyrene

NASA Astrophysics Data System (ADS)

Atmani, O.; Abbès, B.; Abbès, F.; Li, Y. M.; Batkam, S.

2018-05-01

Thermoforming of high impact polystyrene sheets (HIPS) requires technical knowledge on material behavior, mold type, mold material, and process variables. Accurate thermoforming simulations are needed in the optimization process. Determining the behavior of the material under thermoforming conditions is one of the key parameters for an accurate simulation. The aim of this work is to identify the thermomechanical behavior of HIPS in the thermoforming conditions. HIPS behavior is highly dependent on temperature and strain rate. In order to reproduce the behavior of such material, a thermo-elasto-viscoplastic constitutive law was implement in the finite element code ABAQUS. The proposed model parameters are considered as thermo-dependent. The strain-dependence effect is introduced using Prony series. Tensile tests were carried out at different temperatures and strain rates. The material parameters were then identified using a NSGA-II algorithm. To validate the rheological model, experimental blowing tests were carried out on a thermoforming pilot machine. To compare the numerical results with the experimental ones the thickness distribution and the bubble shape were investigated.

Computational Investigation of Technetium(IV) Incorporation into Inverse Spinels: Magnetite (Fe 3 O 4 ) and Trevorite (NiFe 2 O 4 )

DOE Office of Scientific and Technical Information (OSTI.GOV)

Smith, Frances N.; Um, Wooyong; Taylor, Christopher D.

2016-05-17

Iron oxides and oxyhydroxides play an important role in minimizing the mobility of redox-sensitive elements in engineered and natural environments. For the radionuclide technetium-99 (Tc), these phases hold promise as primary hosts for increasing Tc loading into glass waste form matrices, or as secondary sinks during the long-term storage of nuclear materials. Recent experiments show that the inverse spinel, magnetite [Fe(II)Fe(III)2O4], can incorporate Tc(IV) into its octahedral sub-lattice, and in that same class of materials, trevorite [Ni(II)Fe(III)2O4] is also being investigated for its ability to host Tc(IV). However, questions remain regarding the most energetically favorable charge-compensation mechanism for Tc(IV) incorporationmore » in each structure, which will affect Tc behavior under changing waste processing or storage conditions. Here, quantum-mechanical methods were used to evaluate incorporation energies and optimized lattice bonding environments for three different, charge-balanced Tc(IV) incorporation mechanisms in magnetite and trevorite. In both cases, the removal of two octahedral Fe(II) or Ni(II) ions upon the addition of Tc(IV) to an octahedral site is the most stable mechanism, relative to the creation of octahedral Fe(III) defects or increasing octahedral Fe(II) content. Following hydration-energy corrections, Tc(IV) incorporation into magnetite is energetically favorable while an energy barrier exists for trevorite.« less

Summer Institute to Train Data Processing Teachers for the New Oklahoma State-Wide Computer Science System, Phase II. Final Report.

ERIC Educational Resources Information Center

Tuttle, Francis

Twenty-three instructors participated in an 8-week summer institute to develop their technical competency to teach the second year of a 2-year Technical Education Computer Science Program. Instructional material covered the following areas: (1) compiler languages and systems design, (2) cost studies, (3) business organization, (4) advanced…

New Generation Materials and Structures for Nanophotonics and Nanoelectronics

DTIC Science & Technology

2006-04-30

been investigated using thermogravimetric analysis and FTIR spectroscopy. The nanoparticles appear to have excess surfactants on their surface, but...processes. We continued analysis of the vibrational modes of the InP/II- VI core-shell nanoparticles determined by IR and Raman studies, and initiated...photoelectron spectroscopy (XPS), thermogravimetric analysis (TGA), BET surface area analysis , transmission electron microscopy (TEM), and SQUID magnetometry. In

On the Interplay Between Adhesion Strength and Tensile Properties of Thermal Spray Coated Laminates—Part II: Low-Velocity Thermal Spray Coatings

NASA Astrophysics Data System (ADS)

Luo, Xiaotao; Smith, Gregory M.; Sampath, Sanjay

2018-02-01

In this two-part study, uniaxial tensile testing was used to evaluate coating/substrate bonding and compared with traditional ASTM C633 bond pull test results for thermal spray (TS) coated steel laminates. In Part I, the rationale, methodology, and applicability of the test to high-velocity TS coatings were demonstrated. In this Part II, the method was investigated for low-velocity TS processes (air plasma spray and arc spray) on equivalent materials. Ni and Ni-5wt.%Al coatings were deposited on steel substrates with three different roughness levels and tested using both uniaxial tensile and ASTM C633 methods. The results indicate the uniaxial tensile approach provides useful information about the nature of the coating/substrate bonding and goes beyond the traditional bond pull test in providing insightful information on the load sharing processes across the interface. Additionally, this proposed methodology alleviates some of the longstanding shortcomings and potentially reduces error associated with the traditional ASTM C633 test. The mechanisms governing the load transfer between the substrate and the coating were investigated, and the influence of Al in the coating material evaluated.

Hazardous Materials Routing Study Phase II: Analysis of Hazardous Materials Truck Routes in Proximity to the Dallas Central Business District

DOT National Transportation Integrated Search

1985-10-01

This report summarizes the findings from the second phase of a two-part analysis of hazardous materials truck routes in the Dallas-Fort Worth area. Phase II of this study analyzes the risk of transporting hazardous materials on freeways and arterial ...

Synthesis and Characterization of Reduced Graphene Oxide-Supported Nanoscale Zero-Valent Iron (nZVI/rGO) Composites Used for Pb(II) Removal

PubMed Central

Fan, Mingyi; Li, Tongjun; Hu, Jiwei; Cao, Rensheng; Wu, Qing; Wei, Xionghui; Li, Lingyun; Shi, Xuedan; Ruan, Wenqian

2016-01-01

Reduced graphene oxide-supported nanoscale zero-valent iron (nZVI/rGO) composites were prepared by chemical deposition method and were characterized by scanning electron microscopy (SEM), X-ray diffraction (XRD), Raman spectroscopy, N2-sorption and X-ray photoelectron spectroscopy (XPS). Operating parameters for the removal process of Pb(II) ions, such as temperature (20–40 °C), pH (3–5), initial concentration (400–600 mg/L) and contact time (20–60 min), were optimized using a quadratic model. The coefficient of determination (R2 > 0.99) obtained for the mathematical model indicates a high correlation between the experimental and predicted values. The optimal temperature, pH, initial concentration and contact time for Pb(II) ions removal in the present experiment were 21.30 °C, 5.00, 400.00 mg/L and 60.00 min, respectively. In addition, the Pb(II) removal by nZVI/rGO composites was quantitatively evaluated by using adsorption isotherms, such as Langmuir and Freundlich isotherm models, of which Langmuir isotherm gave a better correlation, and the calculated maximum adsorption capacity was 910 mg/g. The removal process of Pb(II) ions could be completed within 50 min, which was well described by the pseudo-second order kinetic model. Therefore, the nZVI/rGO composites are suitable as efficient materials for the advanced treatment of Pb(II)-containing wastewater. PMID:28773813

Synthesis and Characterization of Reduced Graphene Oxide-Supported Nanoscale Zero-Valent Iron (nZVI/rGO) Composites Used for Pb(II) Removal.

PubMed

Fan, Mingyi; Li, Tongjun; Hu, Jiwei; Cao, Rensheng; Wu, Qing; Wei, Xionghui; Li, Lingyun; Shi, Xuedan; Ruan, Wenqian

2016-08-12

Reduced graphene oxide-supported nanoscale zero-valent iron (nZVI/rGO) composites were prepared by chemical deposition method and were characterized by scanning electron microscopy (SEM), X-ray diffraction (XRD), Raman spectroscopy, N₂-sorption and X-ray photoelectron spectroscopy (XPS). Operating parameters for the removal process of Pb(II) ions, such as temperature (20-40 °C), pH (3-5), initial concentration (400-600 mg/L) and contact time (20-60 min), were optimized using a quadratic model. The coefficient of determination ( R ² > 0.99) obtained for the mathematical model indicates a high correlation between the experimental and predicted values. The optimal temperature, pH, initial concentration and contact time for Pb(II) ions removal in the present experiment were 21.30 °C, 5.00, 400.00 mg/L and 60.00 min, respectively. In addition, the Pb(II) removal by nZVI/rGO composites was quantitatively evaluated by using adsorption isotherms, such as Langmuir and Freundlich isotherm models, of which Langmuir isotherm gave a better correlation, and the calculated maximum adsorption capacity was 910 mg/g. The removal process of Pb(II) ions could be completed within 50 min, which was well described by the pseudo-second order kinetic model. Therefore, the nZVI/rGO composites are suitable as efficient materials for the advanced treatment of Pb(II)-containing wastewater.

Equilibrium and kinetics of adsorption of phosphate onto iron-doped activated carbon.

PubMed

Wang, Zhengfang; Nie, Er; Li, Jihua; Yang, Mo; Zhao, Yongjun; Luo, Xingzhang; Zheng, Zheng

2011-08-01

Two series of activated carbons modified by Fe (II) and Fe (III) (denoted as AC/N-Fe(II) and AC/N-Fe(III)), respectively, were used as adsorbents for the removal of phosphate in aqueous solutions. The synthesized adsorbent materials were investigated by different experimental analysis means. The adsorption of phosphate on activated carbons has been studied in kinetic and equilibrium conditions taking into account the adsorbate concentration, temperature, and solution pH as major influential factors. Maximum removals of phosphate are obtained in the pH range of 3.78-6.84 for both adsorbents. Langmuir isotherm adsorption equation well describes the experimental adsorption isotherms. Kinetic studies revealed that the adsorption process followed a pseudo-second order kinetic model. Results suggest that the main phase formed in AC/N-Fe(II) and AC/N-Fe(III) is goethite and akaganeite, respectively; the presence of iron oxides significantly affected the surface area and the pore structure of the activated carbon. Studies revealed that iron-doped activated carbons were effective in removing phosphate. AC/N-Fe(II) has a higher phosphate removal capacity than AC/N-Fe(III), which could be attributed to its better intra-particle diffusion and higher binding energy. The activation energy for adsorption was calculated to be 22.23 and 10.89 kJ mol(-1) for AC/N-Fe(II) and AC/N-Fe(III), respectively. The adsorption process was complex; both surface adsorption and intra-particle diffusion were simultaneously occurring during the process and contribute to the adsorption mechanism.

PROCESS DEVELOPMENT QUARTERLY REPORT. II. PILOT PLANT WORK

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kuhlman, N. ed.

1957-05-01

Progress is reported on the gross solubility of U in digestions of Mallinokrodt feed materials, studies of variables affecting U purity in a TBP hexane extraction cycle, low-acid flowsheet for TBP--hexane extraction process based on a 440 g U/liter in lM HNO/sub 3/ digest liquor, hacking studies in the pilot plant pumperdecanter system, recovery of U from residues from the dingot process, lowering the H level in dingot metal, forging of dingot bar stock, dingot extrusion, fubrication of UO/sub 2/ fuel elements, and the determination of H content of derby and ingot metal. (W.L.H.)

30 CFR 57.22222 - Ventilation materials (I-A, I-B, I-C, II-A, III, V-A, and V-B mines).

Code of Federal Regulations, 2011 CFR

2011-07-01

... 30 Mineral Resources 1 2011-07-01 2011-07-01 false Ventilation materials (I-A, I-B, I-C, II-A, III, V-A, and V-B mines). 57.22222 Section 57.22222 Mineral Resources MINE SAFETY AND HEALTH....22222 Ventilation materials (I-A, I-B, I-C, II-A, III, V-A, and V-B mines). Brattice cloth and...

30 CFR 57.22222 - Ventilation materials (I-A, I-B, I-C, II-A, III, V-A, and V-B mines).

Code of Federal Regulations, 2010 CFR

2010-07-01

... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Ventilation materials (I-A, I-B, I-C, II-A, III, V-A, and V-B mines). 57.22222 Section 57.22222 Mineral Resources MINE SAFETY AND HEALTH....22222 Ventilation materials (I-A, I-B, I-C, II-A, III, V-A, and V-B mines). Brattice cloth and...

Synthesis of organically templated nanoporous tin (II/IV) phosphate for radionuclide and metal sequestration

DOE Office of Scientific and Technical Information (OSTI.GOV)

Wellman, Dawn M.; Mattigod, Shas V.; Parker, Kent E.

2006-03-20

Nanoporous tin (II/IV) phosphate materials, with spherical morphology, have been synthesized using cetyltrimethylammonium chloride (CH3(CH2)15N(CH3)3Cl) as the surfactant. The structure of the material is stable at 500°C; however, partial oxidation of the material occurs with redox conversion of Sn2+ to Sn4+, resulting in a mixed Sn(II)/ Sn(IV) material. Preliminary batch contact studies were conducted to assess the effectiveness of nanoporous tin phosphate, NP-SnPO, in sequestering redox sensitive metals and radionuclides, technetium(VII), neptunium(V), thorium(IV), and a toxic metal, chromium(VI), from aqueous matrices. Results indicate tin (II) phosphate removed > 95% of all contaminants investigated from solution.

Adsorption of transition metal ions from aqueous solutions onto a novel silica gel matrix inorganic-organic composite material.

PubMed

Yin, Ping; Xu, Qiang; Qu, Rongjun; Zhao, Guifang; Sun, Yanzhi

2010-01-15

A novel inorganic-organic composite material silica gel microspheres encapsulated by imidazole functionalized polystyrene (SG-PS-azo-IM) has been synthesized and characterized. This composite material was used to investigate the adsorption of Cr(III), Mn(II), Fe(III), Ni(II), Cu(II), Zn(II), Hg(II), Pb(II), Pd(II), Pt(II), Ag(I), and Au(III) from aqueous solutions, and the research results displayed that SG-PS-azo-IM has the highest adsorption capacity for Au(III). Langmuir and Freundlich isotherm models were applied to analyze the experimental data, the best interpretation for the experimental data was given by the Langmuir isotherm equation, and the maximum adsorption capacity for Au(III) is 1.700 mmol/g. The adsorption selectivity, the dynamic adsorption and desorption properties of SG-PS-azo-IM for Au(III) have also been studied. The results showed that SG-PS-azo-IM had excellent adsorption for Au(III) in four binary ions system, especially in the systems of Au(III)-Zn(II) and Au(III)-Cu(II), and almost Au(III) could be desorbed with the eluent solution of 0.5% thiourea in 1 mol/L HCl. Moreover, this novel composite material was used to preconcentrate Au(III) before its determination by flame atomic adsorption spectrometry. In the initial concentration range of 0.10-0.20 microg/mL, multiple of enrichment could reach 5.28. Thus, silica gel encapsulated by polystyrene coupling with imidazole (SG-PS-azo-IM) is favorable and useful for the removal of transition metal ions, and the high adsorption capacity makes it a good promising candidate material for Au(III) removal.

Utilising Fine and Coarse Recycled Aggregates from the Gulf Region in Concrete

NASA Astrophysics Data System (ADS)

Jones, M. Rod; Halliday, Judith E.; Csetenyi, Laszlo; Zheng, Li; Strompinis, N.

This paper explores the feasibility in utilising materials generated from C&DW to produce a `green' concrete. The two materials that are considered here are, (i) up-sizing silt-size material generated from recycled aggregates to produce a synthetic silt-sand and (ii) processed recycled coarse aggregates (RA) sourced from a Gulf Region landfill site. The work has demonstrated that there is potential for utilising silt wastes into foamed concrete, which can then be crushed to a sand-sized material suitable for use in concrete, however the porous nature of the material has highlighted that the water demand of this RA is high. RAs were characterised to BS EN 12620 and found suitable for use in concrete. The effect of RA on concrete properties is minimal when used up to 35% replacement levels, provided that they are pre-soaked.

A Study of Green's Function Methods Applied to Space Radiation Protection

NASA Technical Reports Server (NTRS)

Heinbockel, John H.

2001-01-01

The purpose of this research was to study the propagation of galactic ions through various materials. Galactic light ions result from the break up of heavy ion particles and their propagation through materials is modeled using the one-dimensional Boltzmann equation. When ions enter materials there can occur (i) the interaction of ions with orbital electrons which causes ionization within the material and (ii) ions collide with atoms causing production of secondary particles which penetrate deeper within the material. These processes are modeled by a continuum model. The basic idea is to place a control volume within the material and examine the change in ion flux across this control volume. In this way on can derive the basic equations for the transport of light and heavy ions in matter. Green's function perturbation methods can then be employed to solve the resulting equations using energy dependent nuclear cross sections.

Development of Processing Techniques for Advanced Thermal Protection Materials

NASA Technical Reports Server (NTRS)

Selvaduray, Guna; Cox, Michael; Srinivasan, Vijayakumar

1997-01-01

Thermal Protection Materials Branch (TPMB) has been involved in various research programs to improve the properties and structural integrity of the existing aerospace high temperature materials. Specimens from various research programs were brought into the analytical laboratory for the purpose of obtaining and refining the material characterization. The analytical laboratory in TPMB has many different instruments which were utilized to determine the physical and chemical characteristics of materials. Some of the instruments that were utilized by the SJSU students are: Scanning Electron Microscopy (SEM), Energy Dispersive X-ray analysis (EDX), X-ray Diffraction Spectrometer (XRD), Fourier Transform-Infrared Spectroscopy (FTIR), Ultra Violet Spectroscopy/Visible Spectroscopy (UV/VIS), Particle Size Analyzer (PSA), and Inductively Coupled Plasma Atomic Emission Spectrometer (ICP-AES). The above mentioned analytical instruments were utilized in the material characterization process of the specimens from research programs such as: aerogel ceramics (I) and (II), X-33 Blankets, ARC-Jet specimens, QUICFIX specimens and gas permeability of lightweight ceramic ablators. In addition to analytical instruments in the analytical laboratory at TPMB, there are several on-going experiments. One particular experiment allows the measurement of permeability of ceramic ablators. From these measurements, physical characteristics of the ceramic ablators can be derived.

Parametric study for use of stainless steel as a material for thermal shield in PIP2IT transferline at FNAL

DOE Office of Scientific and Technical Information (OSTI.GOV)

Rane, Tejas

Proton Improvement Plant – II (PIP-II) has been planned at Fermilab for providing high-intensity proton beams to the laboratory’s experiments. Fermilab has undertaken the PIP-II Injector Test (PIP2IT) for integrated systems testing of critical components comprising the PIP-II front end. PIP2IT includes two cryomodules, to be tested using a pre-existing Supercritical helium refrigerator and distribution box. The PIP2IT transferline connects the Distribution box to the cryomodules of PI2IT. It contains 5 process lines as follows - supercritical 5K He supply and return lines, thermal shield supply(40K) and return(80K) lines and a sub-atmospheric 2K return line. Such cryogenic transferlines are generallymore » provided with cylindrical thermal shields at 80K, enclosing multiple process lines. The thermal shields are cooled by dedicated cooling lines welded/brazed to the shield at a single point along the circumference. Higher thermal diffusivity provides faster cooling and uniformity o f temperature along the shield surface. Hence, Copper/Aluminium is widely used to fabricate thermal shields. However, raw material price, the cost of fabrication depending on standard sizes of pipes/tubes, often drives up the final price of thermal shields. To reduce the cost by making use of easily available stock of standard pipe/tube, it is decided to use stainless steel as a material in thermal shields for the PIP2IT transferline. To this effect, a parametric study has been undertaken to evaluate the suitability of replacing Copper/Aluminium with stainless steel in thermal shields. The low thermal conductivity of steel results in bowing of the shield due to differential temperature distribution along the circumferential direction. The resulting suitable design has limiting parameters in terms of maximum allowable length of a shield section and the maximum allowable heat transfer coefficient for cooling flow. Starting with the design specific to PIP2IT transferline, an at tempt is made to have non-dimensionalised parameters for sim! ilar thermal shields.« less

NDCX-II target experiments and simulations

DOE PAGES

Barnard, J. J.; More, R. M.; Terry, M.; ...

2013-06-13

The ion accelerator NDCX-II is undergoing commissioning at Lawrence Berkeley National Laboratory (LBNL). Its principal mission is to explore ion-driven High Energy Density Physics (HEDP) relevant to Inertial Fusion Energy (IFE) especially in the Warm Dense Matter (WDM) regime. We have carried out hydrodynamic simulations of beam-heated targets for parameters expected for the initial configuration of NDCX-II. For metal foils of order one micron thick (thin targets), the beam is predicted to heat the target in a timescale comparable to the hydrodynamic expansion time for experiments that infer material properties from measurements of the resulting rarefaction wave. We have alsomore » carried out hydrodynamic simulations of beam heating of metallic foam targets several tens of microns thick (thick targets) in which the ion range is shorter than the areal density of the material. In this case shock waves will form and we derive simple scaling laws for the efficiency of conversion of ion energy into kinetic energy of fluid flow. Geometries with a tamping layer may also be used to study the merging of a tamper shock with the end-of-range shock. As a result, this process can occur in tamped, direct drive IFE targets.« less

Quarterly Report: Microchannel-Assisted Nanomaterial Deposition Technology for Photovoltaic Material Production

DOE Office of Scientific and Technical Information (OSTI.GOV)

Palo, Daniel R.

2011-04-26

Quarterly report to ITP for Nanomanufacturing program. Report covers FY11 Q2. The primary objective of this project is to develop a nanomanufacturing process which will reduce the manufacturing energy, environmental discharge, and production cost associated with current nano-scale thin-film photovoltaic (PV) manufacturing approaches. The secondary objective is to use a derivative of this nanomanufacturing process to enable greener, more efficient manufacturing of higher efficiency quantum dot-based photovoltaic cells now under development. The work is to develop and demonstrate a scalable (pilot) microreactor-assisted nanomaterial processing platform for the production, purification, functionalization, and solution deposition of nanomaterials for photovoltaic applications. The highmore » level task duration is shown. Phase I consists of a pilot platform for Gen II PV films along with parallel efforts aimed at Gen III PV quantum dot materials. Status of each task is described.« less

Novel composite material polyoxovanadate@MIL-101(Cr): a highly efficient electrocatalyst for ascorbic acid oxidation.

PubMed

Fernandes, Diana M; Barbosa, André D S; Pires, João; Balula, Salete S; Cunha-Silva, Luís; Freire, Cristina

2013-12-26

A novel hybrid composite material, PMo10V2@MIL-101 was prepared by the encapsulation of the tetra-butylammonium (TBA) salt of the vanadium-substituted phosphomolybdate [PMo10V2O40](5-) (PMo10V2) into the porous metal-organic framework (MOF) MIL-101(Cr). The materials characterization by powder X-ray diffraction, Fourier transform infrared spectra and scanning electron microscopy confirmed the preparation of the composite material without disruption of the MOF porous structure. Pyrolytic graphite electrodes modified with the original components (MIL-101(Cr), PMo10V2), and the composite material PMo10V2@MIL-101 were prepared and their electrochemical responses were studied by cyclic voltammetry. Surface confined redox processes were observed for all the immobilized materials. MIL-101(Cr) showed one-electron reduction process due to chromium centers (Cr(III) → Cr(II)), while PMo10V2 presented five reduction processes: the peak at more positive potentials is attributed to two superimposed 1-electron vanadium reduction processes (V(V) → V(IV)) and the other four peaks to Mo-centred two-electron reduction processes (Mo(VI) → Mo(V)). The electrochemical behavior of the composite material PMo10V2@MIL-101 showed both MIL-101(Cr) and PMo10V2 redox features, although with the splitting of the two vanadium processes and the shift of the Mo- and Cr- centered processes to more negative potentials. Finally, PMo10V2@MIL-101 modified electrode showed outstanding enhanced vanadium-based electrocatalytic properties towards ascorbic acid oxidation, in comparison with the free PMo10V2, as a result of its immobilization into the porous structure of the MOF. Furthermore, PMo10V2@MIL-101 modified electrode showed successful simultaneous detection of ascorbic acid and dopamine.

High-pressure phase transitions, amorphization, and crystallization behaviors in Bi2Se3.

PubMed

Zhao, Jinggeng; Liu, Haozhe; Ehm, Lars; Dong, Dawei; Chen, Zhiqiang; Gu, Genda

2013-03-27

The phase transition, amorphization, and crystallization behaviors of the topological insulator bismuth selenide (Bi2Se3) were discovered by performing in situ high-pressure angle-dispersive x-ray diffraction experiments during an increasing, decreasing, and recycling pressure process. In the compression process, Bi2Se3 transforms from the original rhombohedral structure (phase I(A)) to a monoclinic structure (phase II) at about 10.4 GPa, and further to a body-centered tetragonal structure (phase III) at about 24.5 GPa. When releasing pressure to ambient conditions after the complete transformation from phase II to III, Bi2Se3 becomes an amorphous solid (AM). In the relaxation process from this amorphous state, Bi2Se3 starts crystallizing into an orthorhombic structure (phase I(B)) about five hours after releasing the pressure to ambient. A review of the pressure-induced phase transition behaviors of A2B3-type materials composed from the V and VI group elements is presented.

Continuum Thermodynamics - Part II: Applications and Examples

NASA Astrophysics Data System (ADS)

Albers, Bettina; Wilmanski, Krzysztof

The intention by writing Part II of the book on continuum thermodynamics was the deepening of some issues covered in Part I as well as a development of certain skills in dealing with practical problems of oscopic processes. However, the main motivation for this part is the presentation of main facets of thermodynamics which appear when interdisciplinary problems are considered. There are many monographs on the subjects of solid mechanics and thermomechanics, on fluid mechanics and on coupled fields but most of them cover only special problems in great details which are characteristic for the chosen field. It is rather seldom that relations between these fields are discussed. This concerns, for instance, large deformations of the skeleton of porous materials with diffusion (e.g. lungs), couplings of deformable particles with the fluid motion in suspensions, couplings of adsorption processes and chemical reactions in immiscible mixtures with diffusion, various multi-component aspects of the motion, e.g. of avalanches, such as segregation processes, etc...

A systematic review and appraisal of the quality of practice guidelines for the management of Neisseria gonorrhoeae infections.

PubMed

Dickson, Catherine; Arnason, Trevor; Friedman, Dara Spatz; Metz, Gila; Grimshaw, Jeremy M

2017-11-01

Clinical guidelines help ensure consistent care informed by current evidence. As shifts in antimicrobial resistance continue to influence first-line treatment, up-to-date guidelines are important for preventing treatment failure. A guideline's development process will influence its recommendations and users' trust. To assess the quality of current gonorrhoea guidelines' development processes. Multiple databases. Original and current English-language guidelines targeting health professionals and containing treatment recommendations for uncomplicated gonorrhoea in the general adult population. Two appraisers assessed the guidelines independently using the Appraisal of Guidelines for Research and Evaluation II (AGREE II) tool. Scores were combined as per the AGREE II users' manual. We identified 10 guidelines meeting the inclusion criteria. The quality of the gonorrhoea treatment guidelines varied. Most scored poorly on Rigour of Development ; information on the evidence review process and methods for formulating recommendations was often missing. The WHO Guidelines for the Treatment of Neisseria gonorrhoeae and UK National Guideline for the Management of Gonorrhoea in Adults scored the highest on Rigour of Development . Methods to address conflicts of interest were often not described in the materials reviewed. Implementation of recommendations was often not addressed. By limiting our study to English-language guidelines, a small number of guidelines we identified were excluded. Our analysis was limited to either published or online materials that were readily available to users. We could not differentiate between items addressed in the development process but not documented from items that were not addressed. Gonorrhoea treatment guidelines may slow antimicrobial resistance. Many current guidelines are not in line with the current guideline development best practices; this might undermine the perceived trustworthiness of guidelines. By identifying current limitations, this study can help improve the quality of future guidelines. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/.

Development and fabrication of a graphite polyimide box beam

NASA Technical Reports Server (NTRS)

Nadler, M. A.; Darms, F. J.

1972-01-01

The state-of-the-art of graphite/polyimide structures was evaluated and key design and fabrication issues to be considered in future hardware programs are defined. The fabrication and testing at 500 F of a graphite/polyimide center wing box beam using OV-10A aircraft criteria was accomplished. The baseline design of this box was developed in a series of studies of other advanced composite materials: glass/epoxy, boron/epoxy, and boron/polyimide. The use of this basic design permits ready comparison of the performance of graphite/polyimide with these materials. Modifications to the baseline composite design were made only in those areas effected by the change of materials. Processing studies of graphite fiber polyimide resins systems resulted in the selection of a Modmor II/Gemon L material.

Feasibility studies for the treatment and reuse of contaminated marine sediments.

PubMed

Bonomoa, L; Careghini, A; Dastoli, S; De Propris, L; Ferrari, G; Gabellini, M; Saponaro, S

2009-07-01

This paper presents preliminary results of laboratory tests aimed at evaluating the easibility of the remediation of marine sediments, which are polluted by mercury and petroleum hydrocarbons, dredged at the bay of Augusta (SR, Italy). The treatment is composed of two sequential steps: in the first, a cement-based granular material is produced (based on a high performance concrete approach); then, the volatile and the semi-volatile compounds in the granular material are removed by a thermal desorption step. Treated materials could be reused or put into caissons, according to their mechanical properties and environmental compatibility. The experiments were focused on evaluating the effect of the process parameter values on: (i) the evolution of cement hydration reactions, (ii) thermal desorption removal efficiencies, (iii) leaching behaviour of the treated material.

DIissolution of low enriched uranium from the experimental breeder reactor-II fuel stored at the Idaho National Laboratory

DOE Office of Scientific and Technical Information (OSTI.GOV)

Daniel, G.; Rudisill, T.; Almond, P.

The Idaho National Laboratory (INL) is actively engaged in the development of electrochemical processing technology for the treatment of fast reactor fuels using irradiated fuel from the Experimental Breeder Reactor-II (EBR-II) as the primary test material. The research and development (R&D) activities generate a low enriched uranium (LEU) metal product from the electrorefining of the EBR-II fuel and the subsequent consolidation and removal of chloride salts by the cathode processor. The LEU metal ingots from past R&D activities are currently stored at INL awaiting disposition. One potential disposition pathway is the shipment of the ingots to the Savannah River Sitemore » (SRS) for dissolution in H-Canyon. Carbon steel cans containing the LEU metal would be loaded into reusable charging bundles in the H-Canyon Crane Maintenance Area and charged to the 6.4D or 6.1D dissolver. The LEU dissolution would be accomplished as the final charge in a dissolver batch (following the dissolution of multiple charges of spent nuclear fuel (SNF)). The solution would then be purified and the 235U enrichment downblended to allow use of the U in commercial reactor fuel. To support this potential disposition path, the Savannah River National Laboratory (SRNL) developed a dissolution flowsheet for the LEU using samples of the material received from INL.« less

Molecular Engineering of Platinum(II) Terpyridine Complexes with Tetraphenylethylene-Modified Alkynyl Ligands: Supramolecular Assembly via Pt···Pt and/or π-π Stacking Interactions and the Formation of Various Superstructures.

PubMed

Cheng, Heung-Kiu; Yeung, Margaret Ching-Lam; Yam, Vivian Wing-Wah

2017-10-18

A series of platinum(II) terpyridine complexes with tetraphenylethylene-modified alkynyl ligands has been designed and synthesized. The introduction of the tetraphenylethylene motif has led to aggregation-induced emission (AIE) properties, which upon self-assembly led to the formation of metal-metal-to-ligand charge transfer (MMLCT) behavior stabilized by Pt···Pt and/or π-π interactions. Tuning the steric bulk or hydrophilicity through molecular engineering of the platinum(II) complexes has been found to alter their spectroscopic properties and result in interesting superstructures (including nanorods, nanospheres, nanowires, and nanoleaves) in the self-assembly process. The eye-catching color and emission changes upon varying the solvent compositions may have potential applications in chemosensing materials for the detection of microenvironment changes. Furthermore, the importance of the directional Pt···Pt and/or π-π interactions on the construction of distinctive superstructures has also been examined by UV-vis absorption and emission spectroscopy and transmission electron microscopy. This work represents the interplay of both inter- and intramolecular interactions as well as the energies of the two different chromophoric/luminophoric systems that may open up a new route for the development of platinum(II)-AIE hybrids as functional materials.

46 CFR 197.320 - Diving ladder and stage.

Code of Federal Regulations, 2011 CFR

2011-10-01

... corrosion-resistant material; or (ii) Protected against and maintained free from injurious corrosion. (b... corrosion-resistant material; or (ii) Protected against and maintained free from injurious corrosion. ...

46 CFR 197.320 - Diving ladder and stage.

Code of Federal Regulations, 2010 CFR

2010-10-01

... corrosion-resistant material; or (ii) Protected against and maintained free from injurious corrosion. (b... corrosion-resistant material; or (ii) Protected against and maintained free from injurious corrosion. ...

46 CFR 197.320 - Diving ladder and stage.

Code of Federal Regulations, 2012 CFR

2012-10-01

... corrosion-resistant material; or (ii) Protected against and maintained free from injurious corrosion. (b... corrosion-resistant material; or (ii) Protected against and maintained free from injurious corrosion. ...

46 CFR 197.320 - Diving ladder and stage.

Code of Federal Regulations, 2013 CFR

2013-10-01

... corrosion-resistant material; or (ii) Protected against and maintained free from injurious corrosion. (b... corrosion-resistant material; or (ii) Protected against and maintained free from injurious corrosion. ...

46 CFR 197.320 - Diving ladder and stage.

Code of Federal Regulations, 2014 CFR

2014-10-01

... corrosion-resistant material; or (ii) Protected against and maintained free from injurious corrosion. (b... corrosion-resistant material; or (ii) Protected against and maintained free from injurious corrosion. ...

The road to business process improvement--can you get there from here?

PubMed

Gilberto, P A

1995-11-01

Historically, "improvements" within the organization have been frequently attained through automation by building and installing computer systems. Material requirements planning (MRP), manufacturing resource planning II (MRP II), just-in-time (JIT), computer aided design (CAD), computer aided manufacturing (CAM), electronic data interchange (EDI), and various other TLAs (three-letter acronyms) have been used as the methods to attain business objectives. But most companies have found that installing computer software, cleaning up their data, and providing every employee with training on how to best use the systems have not resulted in the level of business improvements needed. The software systems have simply made management around the problems easier but did little to solve the basic problems. The missing element in the efforts to improve the performance of the organization has been a shift in focus from individual department improvements to cross-organizational business process improvements. This article describes how the Electric Boat Division of General Dynamics Corporation, in conjunction with the Data Systems Division, moved its focus from one of vertical organizational processes to horizontal business processes. In other words, how we got rid of the dinosaurs.

Cassava root husks powder as green adsorbent for the removal of Cu(II) from natural river water

NASA Astrophysics Data System (ADS)

Jorgetto, A. O.; Silva, R. I. V.; Saeki, M. J.; Barbosa, R. C.; Martines, M. A. U.; Jorge, S. M. A.; Silva, A. C. P.; Schneider, J. F.; Castro, G. R.

2014-01-01

Through a series of simple processes, cassava root husks were turned into a fine powder of controlled particle size (63-75 μm). FTIR spectrum demonstrated the existence of alcohol, amine and carboxylic groups; and elemental analysis confirmed the presence of elements of interest such as sulphur, nitrogen and oxygen. Cross-polarized {1H}sbnd 13C NMR technique indicated the existence of methionine and thiamine through the signals observed at 55 ppm and 54 ppm, respectively, and the point of zero charge (pHpzc) was achieved at pH 5.2. The material was applied in solid-phase extraction of Cu(II) via batch experiments. Optimum adsorption pH was found to be in range of 3-6 and in the kinetic experiment the equilibrium was attained in 1 min. The highest adsorption capacity was 0.14 mmol g-1. The adsorption data were fit to the modified Langmuir equation, and the maximum amount of metal species extracted from the solution, Ns, was determined to be ∼0.14 mmol g-1, which is an indicative that the main adsorption mechanism is through chemisorption. Under optimized conditions, the material was utilized in preconcentration experiments, which culminated in an enrichment factor of 41.3-fold. With the aid of the enrichment factor, experiments were carried out to determine the Cu(II) content in tap water and natural water. Preconcentration method was also applied to a certified reference material (1643e) and the concentration found was 23.03 ± 0.79 μg L-1, whereas the specified Cu(II) concentration was 22.7 ± 0.31 μg L-1.

No-Oven, No-Autoclave Composite Processing

NASA Technical Reports Server (NTRS)

Rauscher, Michael D.

2015-01-01

Very large composite structures, such as those used in NASA's Space Launch System, push the boundaries imposed by current autoclaves. New technology is needed to maintain composite performance and free manufacturing engineers from the restraints of curing equipment size limitations. Recent efforts on a Phase II project by Cornerstone Research Group, Inc. (CRG), have advanced the technology and manufacturing readiness levels of a unique two-part epoxy resin system. Designed for room-temperature infusion of a dry carbon preform, the system includes a no-heat-added cure that delivers 350 F composite performance in a matter of hours. This no-oven, no-autoclave (NONA) composite processing eliminates part-size constraints imposed by infrastructure and lowers costs by increasing throughput and reducing capital-specific, process-flow bottlenecks. As a result of the Phase II activity, NONA materials and processes were used to make high-temperature composite tooling suitable for further production of carbon-epoxy laminates and honeycomb/ sandwich-structure composites with an aluminum core. The technology platform involves tooling design, resin infusion processing, composite part design, and resin chemistry. The various technology elements are combined to achieve a fully cured part. The individual elements are not unusual, but they are combined in such a way that enables proper management of the heat generated by the epoxy resin during cure. The result is a self-cured carbon/ epoxy composite part that is mechanically and chemically stable at temperatures up to 350 F. As a result of the successful SBIR effort, CRG has launched NONA Composites as a spinoff subsidiary. The company sells resin to end users, fabricates finished goods for customers, and sells composite tooling made with NONA materials and processes to composite manufacturers.

Ti film deposition process of a plasma focus: Study by an experimental design

NASA Astrophysics Data System (ADS)

Inestrosa-Izurieta, M. J.; Moreno, J.; Davis, S.; Soto, L.

2017-10-01

The plasma generated by plasma focus (PF) devices have substantially different physical characteristics from another plasma, energetic ions and electrons, compared with conventional plasma devices used for plasma nanofabrication, offering new and unique opportunities in the processing and synthesis of Nanomaterials. This article presents the use of a plasma focus of tens of joules, PF-50J, for the deposition of materials sprayed from the anode by the plasma dynamics in the axial direction. This work focuses on the determination of the most significant effects of the technological parameters of the system on the obtained depositions through the use of a statistical experimental design. The results allow us to give a qualitative understanding of the Ti film deposition process in our PF device depending on four different events provoked by the plasma dynamics: i) an electric erosion of the outer material of the anode; ii) substrate ablation generating an interlayer; iii) electron beam deposition of material from the center of the anode; iv) heat load provoking clustering or even melting of the deposition surface.

IN SITU SOURCE TREATMENT OF CR(VI) USING A FE(II)-BASED REDUCTANT BLEND: LONG-TERM MONITORING AND EVALUATION

EPA Science Inventory

The long-term effectiveness of a FeSO4 + Na2S2O4 reductant solution blend for in situ saturated zone treatment of dissolved and solid phase Cr(VI) in a high pH chromite ore processing solid waste (COPSW) fill material was investigated. Two field pilot injection studies were cond...

Perspectives of ruthenium(ii) polyazaaromatic photo-oxidizing complexes photoreactive towards tryptophan-containing peptides and derivatives.

PubMed

Estalayo-Adrián, S; Garnir, K; Moucheron, C

2018-01-04

Ru II polyazaaromatic complexes have been studied with the aim of developing molecular tools for DNA and oligonucleotides. In this context, Ru II -TAP (TAP = 1,4,5,8-tetraazaphenanthrene) complexes have been developed as specific photoreagents targeting the genetic material. The advantage of such compounds is due to the formation of photo-addition products between the Ru-TAP complex and the biomolecule, originating from a photo-induced electron transfer process that takes place between the excited Ru-TAP complex and guanine (G) bases of DNA. This photo-addition has been more recently extended to amino acids in view of applications involving peptides, such as inhibition or photocontrol of proteins. More particularly, tryptophan (Trp) and Trp-containing peptides are also able to be photo-oxidized by Ru II -TAP complexes, leading to the formation of photo-addition products. This mini review focuses on recent advances in the search for Ru II polyazaaromatic photo-oxidizing complexes of interest as molecular tools and photoreagents for Trp-containing peptides and proteins. Different possible future directions in this field are also discussed.

I12: the Joint Engineering, Environment and Processing (JEEP) beamline at Diamond Light Source.

PubMed

Drakopoulos, Michael; Connolley, Thomas; Reinhard, Christina; Atwood, Robert; Magdysyuk, Oxana; Vo, Nghia; Hart, Michael; Connor, Leigh; Humphreys, Bob; Howell, George; Davies, Steve; Hill, Tim; Wilkin, Guy; Pedersen, Ulrik; Foster, Andrew; De Maio, Nicoletta; Basham, Mark; Yuan, Fajin; Wanelik, Kaz

2015-05-01

I12 is the Joint Engineering, Environmental and Processing (JEEP) beamline, constructed during Phase II of the Diamond Light Source. I12 is located on a short (5 m) straight section of the Diamond storage ring and uses a 4.2 T superconducting wiggler to provide polychromatic and monochromatic X-rays in the energy range 50-150 keV. The beam energy enables good penetration through large or dense samples, combined with a large beam size (1 mrad horizontally × 0.3 mrad vertically). The beam characteristics permit the study of materials and processes inside environmental chambers without unacceptable attenuation of the beam and without the need to use sample sizes which are atypically small for the process under study. X-ray techniques available to users are radiography, tomography, energy-dispersive diffraction, monochromatic and white-beam two-dimensional diffraction/scattering and small-angle X-ray scattering. Since commencing operations in November 2009, I12 has established a broad user community in materials science and processing, chemical processing, biomedical engineering, civil engineering, environmental science, palaeontology and physics.

I12: the Joint Engineering, Environment and Processing (JEEP) beamline at Diamond Light Source

PubMed Central

Drakopoulos, Michael; Connolley, Thomas; Reinhard, Christina; Atwood, Robert; Magdysyuk, Oxana; Vo, Nghia; Hart, Michael; Connor, Leigh; Humphreys, Bob; Howell, George; Davies, Steve; Hill, Tim; Wilkin, Guy; Pedersen, Ulrik; Foster, Andrew; De Maio, Nicoletta; Basham, Mark; Yuan, Fajin; Wanelik, Kaz

2015-01-01

I12 is the Joint Engineering, Environmental and Processing (JEEP) beamline, constructed during Phase II of the Diamond Light Source. I12 is located on a short (5 m) straight section of the Diamond storage ring and uses a 4.2 T superconducting wiggler to provide polychromatic and monochromatic X-rays in the energy range 50–150 keV. The beam energy enables good penetration through large or dense samples, combined with a large beam size (1 mrad horizontally × 0.3 mrad vertically). The beam characteristics permit the study of materials and processes inside environmental chambers without unacceptable attenuation of the beam and without the need to use sample sizes which are atypically small for the process under study. X-ray techniques available to users are radiography, tomography, energy-dispersive diffraction, monochromatic and white-beam two-dimensional diffraction/scattering and small-angle X-ray scattering. Since commencing operations in November 2009, I12 has established a broad user community in materials science and processing, chemical processing, biomedical engineering, civil engineering, environmental science, palaeontology and physics. PMID:25931103

49 CFR 173.212 - Non-bulk packagings for solid hazardous materials in Packing Group II.

Code of Federal Regulations, 2011 CFR

2011-10-01

... 49 Transportation 2 2011-10-01 2011-10-01 false Non-bulk packagings for solid hazardous materials... Hazardous Materials Other Than Class 1 and Class 7 § 173.212 Non-bulk packagings for solid hazardous materials in Packing Group II. (a) When § 172.101 of this subchapter specifies that a solid hazardous...

49 CFR 173.212 - Non-bulk packagings for solid hazardous materials in Packing Group II.

Code of Federal Regulations, 2010 CFR

2010-10-01

... 49 Transportation 2 2010-10-01 2010-10-01 false Non-bulk packagings for solid hazardous materials... Hazardous Materials Other Than Class 1 and Class 7 § 173.212 Non-bulk packagings for solid hazardous materials in Packing Group II. (a) When § 172.101 of this subchapter specifies that a solid hazardous...

Enhanced Materials Based on Submonolayer Type-II Quantum Dots

DOE Office of Scientific and Technical Information (OSTI.GOV)

Tamargo, Maria C; Kuskovsky, Igor L.; Meriles, Carlos

2017-04-15

We have investigated a nanostructured material known as sub-monolayer type-II QDs, made from wide bandgap II-VI semiconductors. Our goal is to understand and exploit their tunable optical and electrical properties by taking advantage of the type-II band alignment and quantum confinement effects. Type-II ZnTe quantum dots (QDs) in a ZnSe host are particularly interesting because of their relatively large valence band and conduction band offsets. In the current award we have developed new materials based on sub-monolayer type-II QDs that may be advantageous for photovoltaic and spintronics applications. We have also expanded the structural characterization of these materials by refiningmore » the X-ray diffraction methodologies needed to investigate them. In particular, we have 1) demonstrated ZnCdTe/ZnCdSe type-II QDs materials that have ideal properties for the development of novel high efficiency “intermediate band solar cells”, 2) we developed a comprehensive approach to describe and model the growth of these ultra-small type-II QDs, 3) analysis of the evolution of the photoluminescence (PL) emission, combined with other characterization probes allowed us to predict the size and density of the QDs as a function of the growth conditions, 4) we developed and implemented novel sophisticated X-ray diffraction techniques from which accurate size and shape of the buried type-II QDs could be extracted, 5) a correlation of the shape anisotropy with polarization dependent PL was observed, confirming the QDs detailed shape and providing insight about the effects of this shape anisotropy on the physical properties of the type-II QD systems, and 6) a detailed “time-resolved Kerr rotation” investigation has led to the demonstration of enhanced electron spin lifetimes for the samples with large densities of type-II QDs and an understanding of the interplay between the QDs and Te-isoelectroic centers, a defect that forms in the spacer layers that separate the QDs.« less

Evidence for supernova injection into the solar nebula and the decoupling of r-process nucleosynthesis

PubMed Central

Brennecka, Gregory A.; Borg, Lars E.; Wadhwa, Meenakshi

2013-01-01

The isotopic composition of our Solar System reflects the blending of materials derived from numerous past nucleosynthetic events, each characterized by a distinct isotopic signature. We show that the isotopic compositions of elements spanning a large mass range in the earliest formed solids in our Solar System, calcium–aluminum-rich inclusions (CAIs), are uniform, and yet distinct from the average Solar System composition. Relative to younger objects in the Solar System, CAIs contain positive r-process anomalies in isotopes A < 140 and negative r-process anomalies in isotopes A > 140. This fundamental difference in the isotopic character of CAIs around mass 140 necessitates (i) the existence of multiple sources for r-process nucleosynthesis and (ii) the injection of supernova material into a reservoir untapped by CAIs. A scenario of late supernova injection into the protoplanetary disk is consistent with formation of our Solar System in an active star-forming region of the galaxy. PMID:24101483

Evidence for supernova injection into the solar nebula and the decoupling of r-process nucleosynthesis.

PubMed

Brennecka, Gregory A; Borg, Lars E; Wadhwa, Meenakshi

2013-10-22

The isotopic composition of our Solar System reflects the blending of materials derived from numerous past nucleosynthetic events, each characterized by a distinct isotopic signature. We show that the isotopic compositions of elements spanning a large mass range in the earliest formed solids in our Solar System, calcium-aluminum-rich inclusions (CAIs), are uniform, and yet distinct from the average Solar System composition. Relative to younger objects in the Solar System, CAIs contain positive r-process anomalies in isotopes A < 140 and negative r-process anomalies in isotopes A > 140. This fundamental difference in the isotopic character of CAIs around mass 140 necessitates (i) the existence of multiple sources for r-process nucleosynthesis and (ii) the injection of supernova material into a reservoir untapped by CAIs. A scenario of late supernova injection into the protoplanetary disk is consistent with formation of our Solar System in an active star-forming region of the galaxy.

10 CFR 76.115 - Special nuclear material of moderate strategic significance-Category II.

Code of Federal Regulations, 2012 CFR

2012-01-01

... 10 Energy 2 2012-01-01 2012-01-01 false Special nuclear material of moderate strategic significance-Category II. 76.115 Section 76.115 Energy NUCLEAR REGULATORY COMMISSION (CONTINUED) CERTIFICATION OF GASEOUS DIFFUSION PLANTS Safeguards and Security § 76.115 Special nuclear material of moderate...

10 CFR 76.115 - Special nuclear material of moderate strategic significance-Category II.

Code of Federal Regulations, 2011 CFR

2011-01-01

... 10 Energy 2 2011-01-01 2011-01-01 false Special nuclear material of moderate strategic significance-Category II. 76.115 Section 76.115 Energy NUCLEAR REGULATORY COMMISSION (CONTINUED) CERTIFICATION OF GASEOUS DIFFUSION PLANTS Safeguards and Security § 76.115 Special nuclear material of moderate...

10 CFR 76.115 - Special nuclear material of moderate strategic significance-Category II.

Code of Federal Regulations, 2010 CFR

2010-01-01

... 10 Energy 2 2010-01-01 2010-01-01 false Special nuclear material of moderate strategic significance-Category II. 76.115 Section 76.115 Energy NUCLEAR REGULATORY COMMISSION (CONTINUED) CERTIFICATION OF GASEOUS DIFFUSION PLANTS Safeguards and Security § 76.115 Special nuclear material of moderate...

10 CFR 76.115 - Special nuclear material of moderate strategic significance-Category II.

Code of Federal Regulations, 2013 CFR

2013-01-01

... 10 Energy 2 2013-01-01 2013-01-01 false Special nuclear material of moderate strategic significance-Category II. 76.115 Section 76.115 Energy NUCLEAR REGULATORY COMMISSION (CONTINUED) CERTIFICATION OF GASEOUS DIFFUSION PLANTS Safeguards and Security § 76.115 Special nuclear material of moderate...

10 CFR 76.115 - Special nuclear material of moderate strategic significance-Category II.

Code of Federal Regulations, 2014 CFR

2014-01-01

... 10 Energy 2 2014-01-01 2014-01-01 false Special nuclear material of moderate strategic significance-Category II. 76.115 Section 76.115 Energy NUCLEAR REGULATORY COMMISSION (CONTINUED) CERTIFICATION OF GASEOUS DIFFUSION PLANTS Safeguards and Security § 76.115 Special nuclear material of moderate...

Modeling the self-assembly of ordered nanoporous materials

DOE Office of Scientific and Technical Information (OSTI.GOV)

Monson, Peter; Auerbach, Scott

This report describes progress on a collaborative project on the multiscale modeling of the assembly processes in the synthesis of nanoporous materials. Such materials are of enormous importance in modern technology with application in the chemical process industries, biomedicine and biotechnology as well as microelectronics. The project focuses on two important classes of materials: i) microporous crystalline materials, such as zeolites, and ii) ordered mesoporous materials. In the first case the pores are part of the crystalline structure, while in the second the structures are amorphous on the atomistic length scale but where surfactant templating gives rise to order onmore » the length scale of 2 - 20 nm. We have developed a modeling framework that encompasses both these kinds of materials. Our models focus on the assembly of corner sharing silica tetrahedra in the presence of structure directing agents. We emphasize a balance between sufficient realism in the models and computational tractibility given the complex many-body phenomena. We use both on-lattice and off-lattice models and the primary computational tools are Monte Carlo simulations with sampling techniques and ensembles appropriate to specific situations. Our modeling approach is the first to capture silica polymerization, nanopore crystallization, and mesopore formation through computer-simulated self assembly.« less

Synthesis, characterization and investigation of electrochemical and spectroelectrochemical properties of non-peripherally tetra-5-methyl-1,3,4-thiadiazole substituted copper(II) iron(II) and oxo-titanium (IV) phthalocyanines

NASA Astrophysics Data System (ADS)

Demirbaş, Ümit; Akyüz, Duygu; Akçay, Hakkı Türker; Barut, Burak; Koca, Atıf; Kantekin, Halit

2017-09-01

In this study novel substituted phthalonitrile (3) and non-peripherally tetra 5-Methyl-1,3,4-thiadiazole substituted copper(II) (4), iron(II) (5) and oxo-titanium (IV) (6) phthalocyanines were synthesized. These novel compounds were fully characterized by FT-IR, 1H NMR, UV-vis and MALDI-TOF mass spectroscopic techniques. Voltammetric and in situ spectroelectrochemical measurements were performed for metallo-phthalocyanines (4-6). TiIVOPc and FeIIPc showed metal-based and ligand-based electron transfer reactions while CuIIPc shows only ligand-based electron transfer reaction. Voltammetric measurements indicated that the complexes have reversible, diffusion controlled and one-electron redox reactions. The assignments of the redox processes and color of the electrogenerated species of the complexes were determined with in-situ spectroelectrochemical and electrocolorimetric measurements. These measurements showed that the complexes can be used as the electrochromic materials for various display technologies.

Improved Tubulars for Better Economics in Deep Gas Well Drilling Using Microwave Technology

DOE Office of Scientific and Technical Information (OSTI.GOV)

Dinesh Agrawal

2006-09-30

The main objective of the entire research program has been to improve the rate-of-penetration in deep hostile environments by improving the life cycle and performance of coiled-tubing, an important component of a deep well drilling system for oil and gas exploration, by utilizing the latest developments in the microwave materials technology. Based on the results of the Phase I and insurmountable difficulties faced in the extrusion and de-waxing processes, the approach of achieving the goals of the program was slightly changed in the Phase II in which an approach of microwave sintering combined with Cold Isostatic Press (CIP) and joiningmore » (by induction or microwave) has been adopted. This process can be developed into a semicontinuous sintering process if the CIP can produce parts fast enough to match the microwave sintering rates. The main objective of the Phase II research program is to demonstrate the potential to economically manufacture microwave processed coiled tubing with improved performance for extended useful life under hostile coiled tubing drilling conditions. After the completion of the Phase II, it is concluded that scale up and sintering of a thin wall common O.D. size tubing that is widely used in the market is still to be proved and further experimentation and refinement of the sintering process is needed in Phase III. Actual manufacturing capability of microwave sintered, industrial quality, full length tubing will most likely require several million dollars of investment.« less

Improved Tubulars for Better Economics in Deep Gas Well Drilling using Microwave Technology

DOE Office of Scientific and Technical Information (OSTI.GOV)

Dinesh Agrawal; Paul Gigl; Mark Hunt

2007-07-31

The main objective of the entire research program has been to improve the rate-of-penetration in deep hostile environments by improving the life cycle and performance of coiled-tubing, an important component of a deep well drilling system for oil and gas exploration, by utilizing the latest developments in the microwave materials technology. Based on the results of the Phase I and insurmountable difficulties faced in the extrusion and de-waxing processes, the approach of achieving the goals of the program was slightly changed in the Phase II in which an approach of microwave sintering combined with Cold Isostatic Press (CIP) and joiningmore » (by induction or microwave) has been adopted. This process can be developed into a semicontinuous sintering process if the CIP can produce parts fast enough to match the microwave sintering rates. The main objective of the Phase II research program is to demonstrate the potential to economically manufacture microwave processed coiled tubing with improved performance for extended useful life under hostile coiled tubing drilling conditions. After the completion of the Phase II, it is concluded that scale up and sintering of a thin wall common O.D. size tubing that is widely used in the market is still to be proved and further experimentation and refinement of the sintering process is needed in Phase III. Actual manufacturing capability of microwave sintered, industrial quality, full length tubing will most likely require several million dollars of investment.« less

Novel bright-emission small-molecule NIR-II fluorophores for in vivo tumor imaging and image-guided surgery† †Electronic supplementary information (ESI) available. See DOI: 10.1039/c7sc00251c Click here for additional data file.

PubMed Central

Sun, Yao; Ding, Mingmin; Zeng, Xiaodong; Xiao, Yuling; Wu, Huaping; Zhou, Hui; Ding, Bingbing; Qu, Chunrong; Hou, Wei; Er-bu, AGA; Zhang, Yejun; Cheng, Zhen

2017-01-01

Though high brightness and biocompatible small NIR-II dyes are highly desirable in clinical or translational cancer research, their fluorescent cores are relatively limited and their synthetic processes are somewhat complicated. Herein, we have explored the design and synthesis of novel NIR-II fluorescent materials (H1) without tedious chromatographic isolation with improved fluorescence performance (QY ≈ 2%) by introducing 2-amino 9,9-dialkyl-substituted fluorene as a donor into the backbone. Several types of water-soluble and biocompatible NIR-II probes: SXH, SDH, and H1 NPs were constructed via different chemical strategies based on H1, and then their potential to be used in in vivo tumor imaging and image-guided surgery in the NIR-II region was explored. High levels of uptake were obtained for both passive and active tumor targeting probes SXH and SDH. Furthermore, high resolution imaging of blood vessels on tumors and the whole body of living mice using H1 NPs for the first time has demonstrated precise NIR-II image-guided sentinel lymph node (SLN) surgery. PMID:28507722

Removal of copper and nickel from water using nanocomposite of magnetic hydroxyapatite nanorods

NASA Astrophysics Data System (ADS)

Thanh, Dong Nguyen; Novák, Pavel; Vejpravova, Jana; Vu, Hong Nguyen; Lederer, Jaromír; Munshi, Tasnim

2018-06-01

A nanocomposite of magnetic hydroxyapatite was synthesized and tested as an adsorbent for the removal of copper (Cu (II)) and nickel (Ni(II)) from aqueous solution. The adsorbent was investigated using Transmission Electron Microscopy (TEM), Scanning Electron Microscopy equipped with an Energy Dispersive Spectrometer (SEM/EDS), X-ray powder diffraction (XRD) and the Brunauer-Elmet-Teller nitrogen adsorption technique (BET-N2 adsorption). Batch experiments were carried out to determine and compare the adsorption parameters of Fe3O4 and its composite with hydroxyapatite. It was found that the adsorbent is nanostructured and has a specific surface area of 101.2 m2 g-1. The Langmuir adsorption isotherm was found to be an appropriate model to describe the adsorption processes, showing the adsorption capacities of Cu(II) and Ni(II) of 48.78 mg g-1 and 29.07 mg g-1, respectively. In addition to the high adsorption capacity, the fully-adsorbed material could be easily separated from aqueous media using an external magnetic field. These results suggested that the utilization of new hydroxyapatite - Fe3O4 nanocomposite for the removal of Cu(II) and Ni(II) is a promising method in water technology.

The importance of Thermo-Hydro-Mechanical couplings and microstructure to strain localization in 3D continua with application to seismic faults. Part II: Numerical implementation and post-bifurcation analysis

NASA Astrophysics Data System (ADS)

Rattez, Hadrien; Stefanou, Ioannis; Sulem, Jean; Veveakis, Manolis; Poulet, Thomas

2018-06-01

In this paper we study the phenomenon of localization of deformation in fault gouges during seismic slip. This process is of key importance to understand frictional heating and energy budget during an earthquake. A infinite layer of fault gouge is modeled as a Cosserat continuum taking into account Thermo-Hydro-Mechanical (THM) couplings. The theoretical aspects of the problem are presented in the companion paper (Rattez et al., 2017a), together with a linear stability analysis to determine the conditions of localization and estimate the shear band thickness. In this Part II of the study, we investigate the post-bifurcation evolution of the system by integrating numerically the full system of non-linear equations using the method of Finite Elements. The problem is formulated in the framework of Cosserat theory. It enables to introduce information about the microstructure of the material in the constitutive equations and to regularize the mathematical problem in the post-localization regime. We emphasize the influence of the size of the microstructure and of the softening law on the material response and the strain localization process. The weakening effect of pore fluid thermal pressurization induced by shear heating is examined and quantified. It enhances the weakening process and contributes to the narrowing of shear band thickness. Moreover, due to THM couplings an apparent rate-dependency is observed, even for rate-independent material behavior. Finally, comparisons show that when the perturbed field of shear deformation dominates, the estimation of the shear band thickness obtained from linear stability analysis differs from the one obtained from the finite element computations, demonstrating the importance of post-localization numerical simulations.

Silica-bound copper(II)triazacyclononane as a phosphate esterase: effect of linker length and surface hydrophobicity.

PubMed

Bodsgard, Brett R; Clark, Robert W; Ehrbar, Anthony W; Burstyn, Judith N

2009-04-07

A series of silica-bound Cu(ii) triazacyclononane materials was prepared to study the effect of linker length and surface hydrophobicity on the hydrolysis of phosphate esters. The general synthetic approach for these heterogeneous reagents was rhodium-catalyzed hydrosilation between an alkenyl-modified triazacyclononane and hydride-modified silica followed by metallation with a Cu(ii) salt. Elemental analysis confirmed that organic functionalization of the silica gel was successful and provided an estimate of the surface concentration of triazacyclononane. EPR spectra were consistent with square pyramidal Cu(ii), indicating that Cu(ii) ions were bound to the immobilized macrocycles. The hydrolytic efficacies of these heterogeneous reagents were tested with bis(p-nitrophenyl)phosphate (BNPP) and diethyl 4-nitrophenyl phosphate (paraoxon). The agent that performed best was an octyl-linked, propanol-blocked material. This material had the most hydrophilic surface and the most accessible active site, achieving a rate maximum on par with the other materials, but in fewer cycles and without an induction period.

Plumbing Specialist II & III, 3-22. Military Curriculum Materials for Vocational and Technical Education.

ERIC Educational Resources Information Center

Ohio State Univ., Columbus. National Center for Research in Vocational Education.

These military-developed curriculum materials consist of a course description, course chart, plan of instruction, lesson plans, study guides, and workbooks for use in training plumbing specialists II and III. Covered in the course blocks are building waste systems and exterior and interior supply systems. Course block II, on building waste…

Recovery of 238PuO2 by Molten Salt Oxidation Processing of 238PuO2 Contaminated Combustibles (Part II)

NASA Astrophysics Data System (ADS)

Remerowski, Mary Lynn; Dozhier, C.; Krenek, K.; VanPelt, C. E.; Reimus, M. A.; Spengler, D.; Matonic, J.; Garcia, L.; Rios, E.; Sandoval, F.; Herman, D.; Hart, R.; Ewing, B.; Lovato, M.; Romero, J. P.

2005-02-01

Pu-238 heat sources are used to fuel radioisotope thermoelectric generators (RTG) used in space missions. The demand for this fuel is increasing, yet there are currently no domestic sources of this material. Much of the fuel is material reprocessed from other sources. One rich source of Pu-238 residual material is that from contaminated combustible materials, such as cheesecloth, ion exchange resins and plastics. From both waste minimization and production efficiency standpoints, the best solution is to recover this material. One way to accomplish separation of the organic component from these residues is a flameless oxidation process using molten salt as the matrix for the breakdown of the organic to carbon dioxide and water. The plutonium is retained in the salt, and can be recovered by dissolution of the carbonate salt in an aqueous solution, leaving the insoluble oxide behind. Further aqueous scrap recovery processing is used to purify the plutonium oxide. Recovery of the plutonium from contaminated combustibles achieves two important goals. First, it increases the inventory of Pu-238 available for heat source fabrication. Second, it is a significant waste minimization process. Because of its thermal activity (0.567 W per gram), combustibles must be packaged for disposition with much lower amounts of Pu-238 per drum than other waste types. Specifically, cheesecloth residues in the form of pyrolyzed ash (for stabilization) are being stored for eventual recovery of the plutonium.

Recovery of 238PuO2 by Molten Salt Oxidation Processing of 238PuO2 Contaminated Combustibles (Part II)

DOE Office of Scientific and Technical Information (OSTI.GOV)

Remerowski, Mary Lynn; Dozhier, C.; Krenek, K.

2005-02-06

Pu-238 heat sources are used to fuel radioisotope thermoelectric generators (RTG) used in space missions. The demand for this fuel is increasing, yet there are currently no domestic sources of this material. Much of the fuel is material reprocessed from other sources. One rich source of Pu-238 residual material is that from contaminated combustible materials, such as cheesecloth, ion exchange resins and plastics. From both waste minimization and production efficiency standpoints, the best solution is to recover this material. One way to accomplish separation of the organic component from these residues is a flameless oxidation process using molten salt asmore » the matrix for the breakdown of the organic to carbon dioxide and water. The plutonium is retained in the salt, and can be recovered by dissolution of the carbonate salt in an aqueous solution, leaving the insoluble oxide behind. Further aqueous scrap recovery processing is used to purify the plutonium oxide. Recovery of the plutonium from contaminated combustibles achieves two important goals. First, it increases the inventory of Pu-238 available for heat source fabrication. Second, it is a significant waste minimization process. Because of its thermal activity (0.567 W per gram), combustibles must be packaged for disposition with much lower amounts of Pu-238 per drum than other waste types. Specifically, cheesecloth residues in the form of pyrolyzed ash (for stabilization) are being stored for eventual recovery of the plutonium.« less

Materials and systems for unassisted photoelectrochemical solar fuels production (Conference Presentation)

NASA Astrophysics Data System (ADS)

Lee, Jae Sung

2016-10-01

About 400 semiconductor solids are known to have photocatalytic activity for water splitting. Yet there is no single material that could satisfy all the requirements for desired photocatalysts: i) suitable band gap energy (1.7 eV< Eg < 2.3 eV) for high efficiency, ii) proper band position for reduction and/or oxidation of water, iii) long-term stability in aqueous solutions, iv) low cost, v) high crystallinity, and vi) high conductivity. Hence, in the selection of photocatalytic materials, we better start from intrinsically stable materials made of earth-abundant elements. The band bap energy is also the primary consideration to absorb ample amount of solar energy of wide wavelength spectrum. It sets the limit of theoretically maximum efficiency and it could also be extended by band engineering techniques. Upon selection of the candidate materials, we can also modify the materials for full utilization their potentials. The main path of efficiency loss in PEC water splitting process is recombination of photoelectrons and holes. We discuss the material designs including i) p-n heterojunction photoanodes for effective electron-hole separation, ii) electron highway to facilitate interparticle electron transfer, iii) metal or anion doping to improve conductivity of the semiconductor and to extend the range of light absorption, iv) one-dimensional nanomaterials to secure a short hole diffusion distance and vectoral electron transfer, and v) loading co-catalysts for facile charge separation. High efficiency has been demonstrated for all these examples due to efficient electron-hole separation. Finally, total systems for unassisted solar fuel production are demonstrated.

Commercially pure titanium (cp-Ti) versus titanium alloy (Ti6Al4V) materials as bone anchored implants - Is one truly better than the other?

PubMed

Shah, Furqan A; Trobos, Margarita; Thomsen, Peter; Palmquist, Anders

2016-05-01

Commercially pure titanium (cp-Ti) and titanium alloys (typically Ti6Al4V) display excellent corrosion resistance and biocompatibility. Although the chemical composition and topography are considered important, the mechanical properties of the material and the loading conditions in the host have, conventionally, influenced material selection for different clinical applications: predominantly Ti6Al4V in orthopaedics while cp-Ti in dentistry. This paper attempts to address three important questions: (i) To what extent do the surface properties differ when cp-Ti and Ti6Al4V materials are manufactured with the same processing technique?, (ii) Does bone tissue respond differently to the two materials, and (iii) Do bacteria responsible for causing biomaterial-associated infections respond differently to the two materials? It is concluded that: (i) Machined cp-Ti and Ti6Al4V exhibit similar surface morphology, topography, phase composition and chemistry, (ii) Under experimental conditions, cp-Ti and Ti6Al4V demonstrate similar osseointegration and biomechanical anchorage, and (iii) Experiments in vitro fail to disclose differences between cp-Ti and Ti6Al4V to harbour Staphylococcus epidermidis growth. No clinical comparative studies exist which could determine if long-term, clinical differences exist between the two types of bulk materials. It is debatable whether cp-Ti or Ti6Al4V exhibit superiority over the other, and further comparative studies, particularly in a clinical setting, are required. Copyright © 2016 Elsevier B.V. All rights reserved.

A framework for sustainable nanomaterial selection and design based on performance, hazard, and economic considerations.

PubMed

Falinski, Mark M; Plata, Desiree L; Chopra, Shauhrat S; Theis, Thomas L; Gilbertson, Leanne M; Zimmerman, Julie B

2018-04-30

Engineered nanomaterials (ENMs) and ENM-enabled products have emerged as potentially high-performance replacements to conventional materials and chemicals. As such, there is an urgent need to incorporate environmental and human health objectives into ENM selection and design processes. Here, an adapted framework based on the Ashby material selection strategy is presented as an enhanced selection and design process, which includes functional performance as well as environmental and human health considerations. The utility of this framework is demonstrated through two case studies, the design and selection of antimicrobial substances and conductive polymers, including ENMs, ENM-enabled products and their alternatives. Further, these case studies consider both the comparative efficacy and impacts at two scales: (i) a broad scale, where chemical/material classes are readily compared for primary decision-making, and (ii) within a chemical/material class, where physicochemical properties are manipulated to tailor the desired performance and environmental impact profile. Development and implementation of this framework can inform decision-making for the implementation of ENMs to facilitate promising applications and prevent unintended consequences.

40 CFR 280.20 - Performance standards for new UST systems.

Code of Federal Regulations, 2010 CFR

2010-07-01

... protected in the following manner: (i) The tank is coated with a suitable dielectric material; (ii) Field... suitable dielectric material; (ii) Field-installed cathodic protection systems are designed by a corrosion...

40 CFR 280.20 - Performance standards for new UST systems.

Code of Federal Regulations, 2011 CFR

2011-07-01

... protected in the following manner: (i) The tank is coated with a suitable dielectric material; (ii) Field... suitable dielectric material; (ii) Field-installed cathodic protection systems are designed by a corrosion...

Luminescent zinc(ii) and copper(i) complexes for high-performance solution-processed monochromic and white organic light-emitting devices† †Electronic supplementary information (ESI) available: Experimental procedures, device performances, and computational details. CCDC 1054456, 1400003 and 1400004. For ESI and crystallographic data in CIF or other electronic format see DOI: 10.1039/c4sc03161j Click here for additional data file. Click here for additional data file.

PubMed Central

Cheng, Gang; So, Gary Kwok-Ming; To, Wai-Pong; Chen, Yong; Kwok, Chi-Chung; Ma, Chensheng; Guan, Xiangguo; Chang, Xiaoyong; Kwok, Wai-Ming

2015-01-01

The synthesis and spectroscopic properties of luminescent tetranuclear zinc(ii) complexes of substituted 7-azaindoles and a series of luminescent copper(i) complexes containing 7,8-bis(diphenylphosphino)-7,8-dicarba-nido-undecaborate ligand are described. These complexes are stable towards air and moisture. Thin film samples of the luminescent copper(i) complexes in 2,6-dicarbazolo-1,5-pyridine and zinc(ii) complexes in poly(methyl methacrylate) showed emission quantum yields of up to 0.60 (for Cu-3) and 0.96 (for Zn-1), respectively. Their photophysical properties were examined by ultrafast time-resolved emission spectroscopy, temperature dependent emission lifetime measurements and density functional theory calculations. Monochromic blue and orange solution-processed OLEDs with these Zn(ii) and Cu(i) complexes as light-emitting dopants have been fabricated, respectively. Maximum external quantum efficiency (EQE) of 5.55% and Commission Internationale de l'Eclairage (CIE) coordinates of (0.16, 0.19) were accomplished with the optimized Zn-1-OLED while these values were, respectively 15.64% and (0.48, 0.51) for the optimized Cu-3-OLED. Solution-processed white OLEDs having maximum EQE of 6.88%, CIE coordinates of (0.42, 0.44), and colour rendering index of 81 were fabricated by using these luminescent Zn(ii) and Cu(i) complexes as blue and orange light-emitting dopant materials, respectively. PMID:29142704

PHASE I MATERIALS PROPERTY DATABASE DEVELOPMENT FOR ASME CODES AND STANDARDS

DOE Office of Scientific and Technical Information (OSTI.GOV)

Ren, Weiju; Lin, Lianshan

2013-01-01

To support the ASME Boiler and Pressure Vessel Codes and Standard (BPVC) in modern information era, development of a web-based materials property database is initiated under the supervision of ASME Committee on Materials. To achieve efficiency, the project heavily draws upon experience from development of the Gen IV Materials Handbook and the Nuclear System Materials Handbook. The effort is divided into two phases. Phase I is planned to deliver a materials data file warehouse that offers a depository for various files containing raw data and background information, and Phase II will provide a relational digital database that provides advanced featuresmore » facilitating digital data processing and management. Population of the database will start with materials property data for nuclear applications and expand to data covering the entire ASME Code and Standards including the piping codes as the database structure is continuously optimized. The ultimate goal of the effort is to establish a sound cyber infrastructure that support ASME Codes and Standards development and maintenance.« less

MATERIALS DEGRADATION ANALYSIS AND DEVELOPMENT TO ENABLE ULTRA LOW COST, WEB-PROCESSED WHITE P-OLED FOR SSL

DOE Office of Scientific and Technical Information (OSTI.GOV)

DR. DEVIN MACKENZIE

2011-12-13

Progress over Phase II of DE-FG02-07ER86293 'Materials Degradation Analysis and Development to Enable Ultra Low Cost, Web-Processed White P-OLED for SSL' was initially rapid in terms of device performance improvements. We exceeded our device luminance lifetime goals for printed flexible white OLEDs as laid out in our project proposal. Our Phase II performance target was to demonstrate >1500 hours luminance lifetime at 100 Cd/m2 from a printed flexible device. We now have R&D devices well in excess of 8000 hrs lifetime at 100 Cd/m2, tested in air. We also were able to produce devices which met the voltage target ofmore » >1500 hours below 15V operation. After completing the initial performance milestones, we went on to focus on color-related degradation issues which were cited as important to commercialization of the technology by our manufacturing partners. We also put additional focus on cathode work as the active material development that occurred over the STTR time period required an adaptation of the cathode from the original cathode formulations which were developed based on previous generation active layer materials. We were able to improve compatibility of the cathode with some of the newer generation active layer materials and improve device yield and voltage behavior. An additional objective of the initial Phase II was to further develop the underlying manufacturing technology and real-life product specifications. This is a key requirement that must be met to ensure eventual commercialization of this DOE-funded technology. The link between commercial investment for full commercialization and R&D efforts in OLED solid State Lighting is often a large one. Add-Vision's lower cost, printed OLED manufacturing approach is an attraction, but close engagement with manufacturing partners and addressing customer specifications is a very important link. Manufacturing technology encompasses development of moisture reduction encapsulation technology, improved cost performance, and reductions in operating voltage through thinner and higher uniformity active device layers. We have now installed a pilot encapsulation system at AVI for controlled, high throughput lamination encapsulation of flexible OLEDs in a novel process. Along with this, we have developed, with our materials supply partners, adhesives, barrier films and other encapsulation materials and we are showing total air product lifetimes in the 2-4 years range from a process consistent with our throughput goals of {approx}1M device per month ({approx}30,000 sq. ft. of processed OLEDs). Within the last year of the project, we have been working to introduce the manufacturing improvements made in our LEP deposition and annealing process to our commercial partners. Based on the success of this, a pilot scale-up program was begun. During this process, Add-Vision was acquired by a strategic partner, in no small part, because of the promise of future success of the technology as evidenced by our commercial partners pilot scale-up plans. Overall, the performance, manufacturing and product work in this project has been successful. Additional analysis and device work at LBL has also shown a unique adhesion change with device bias stressing which may result from active layer polymer cross-linking during bias stressing of device. It was shown that even small bias stresses, as a fraction of a full device lifetime stress period, result in measurable chemical change in the device. Further work needs to be conducted to fully understand the chemical nature of this interaction. Elucidation of this effect would enable doped OLED formulation to be engineered to suppress this effect and further extend lifetimes and reduce voltage climb.« less

Preparation of thiol-functionalized activated carbon from sewage sludge with coal blending for heavy metal removal from contaminated water.

PubMed

Li, Juan; Xing, Xing; Li, Jiao; Shi, Mei; Lin, Aijun; Xu, Congbin; Zheng, Jianzhong; Li, Ronghua

2018-03-01

Sewage sludge produced from wastewater treatment is a pressing environmental issue. Mismanagement of the massive amount of sewage sludge would threat our valuble surface and shallow ground water resources. Use of activated carbon prepared from carbonization of these sludges for heavy metal removal can not only minimize and stabilize these hazardous materials but also realize resources reuse. In this study, thiol-functionalized activated carbon was synthesized from coal-blended sewage sludge, and its capacity was examined for removing Cu(II), Pb(II), Cd(II) and Ni(II) from water. Pyrolysis conditions to prepare activated carbons from the sludge and coal mixture were examined, and the synthesized material was found to achieve the highest BET surface area of 1094 m 2 /g under 500 °C and 30 min. Batch equilibrium tests indicated that the thiol-functionalized activated carbon had a maximum sorption capacity of 238.1, 96.2, 87.7 and 52.4 mg/g for Pb(II), Cd(II), Cu(II) and Ni(II) removal from water, respectively. Findings of this study suggest that thiol-functionalized activated carbon prepared from coal-blended sewage sludge would be a promising sorbent material for heavy metal removal from waters contaminated with Cu(II), Pb(II), Cd(II) and Ni(II). Copyright © 2017 Elsevier Ltd. All rights reserved.

Process for treating alkaline wastes for vitrification

DOEpatents

Hsu, Chia-lin W.

1994-01-01

According to its major aspects and broadly stated, the present invention is a process for treating alkaline waste materials, including high level radioactive wastes, for vitrification. The process involves adjusting the pH of the wastes with nitric acid, adding formic acid (or a process stream containing formic acid) to reduce mercury compounds to elemental mercury and MnO{sub 2} to the Mn(II) ion, and mixing with class formers to produce a melter feed. The process minimizes production of hydrogen due to noble metal-catalyzed formic acid decomposition during, treatment, while producing a redox-balanced feed for effective melter operation and a quality glass product. An important feature of the present invention is the use of different acidifying and reducing, agents to treat the wastes. The nitric acid acidifies the wastes to improve yield stress and supplies acid for various reactions; then the formic acid reduces mercury compounds to elemental mercury and MnO{sub 2}) to the Mn(II) ion. When the pH of the waste is lower, reduction of mercury compounds and MnO{sub 2}) is faster and less formic acid is needed, and the production of hydrogen caused by catalytically-active noble metals is decreased.

Color stable manganese-doped phosphors

DOEpatents

Lyons, Robert Joseph; Setlur, Anant Achyut; Deshpande, Anirundha Rajendra; Grigorov, Ljudmil Slavchev

2014-04-29

A lighting apparatus capable of emitting white light includes a semiconductor light source; and a phosphor material radiationally coupled to the light source. The phosphor material includes a color-stable Mn.sup.+4 doped phosphor prepared by a process including providing a phosphor of formula I; A.sub.x[MF.sub.y]:Mn.sup.+4 I and contacting the phosphor in particulate form with a saturated solution of a composition of formula II in aqueous hydrofluoric acid; A.sub.x[MF.sub.y]; II wherein A is Li, Na, K, Rb, Cs, NR.sub.4 or a combination thereof; M is Si, Ge, Sn, Ti, Zr, Al, Ga, In, Sc, Y, La, Nb, Ta, Bi, Gd, or a combination thereof; R is H, lower alkyl, or a combination thereof; x is the absolute value of the charge of the [MF.sub.y] ion; and y is 5, 6 or 7. In particular embodiments, M is Si, Ge, Sn, Ti, Zr, or a combination thereof.

EASY-II Renaissance: n, p, d, α, γ-induced Inventory Code System

NASA Astrophysics Data System (ADS)

Sublet, J.-Ch.; Eastwood, J. W.; Morgan, J. G.

2014-04-01

The European Activation SYstem has been re-engineered and re-written in modern programming languages so as to answer today's and tomorrow's needs in terms of activation, transmutation, depletion, decay and processing of radioactive materials. The new FISPACT-II inventory code development project has allowed us to embed many more features in terms of energy range: up to GeV; incident particles: alpha, gamma, proton, deuteron and neutron; and neutron physics: self-shielding effects, temperature dependence and covariance, so as to cover all anticipated application needs: nuclear fission and fusion, accelerator physics, isotope production, stockpile and fuel cycle stewardship, materials characterization and life, and storage cycle management. In parallel, the maturity of modern, truly general purpose libraries encompassing thousands of target isotopes such as TENDL-2012, the evolution of the ENDF-6 format and the capabilities of the latest generation of processing codes PREPRO, NJOY and CALENDF have allowed the activation code to be fed with more robust, complete and appropriate data: cross sections with covariance, probability tables in the resonance ranges, kerma, dpa, gas and radionuclide production and 24 decay types. All such data for the five most important incident particles (n, p, d, α, γ), are placed in evaluated data files up to an incident energy of 200 MeV. The resulting code system, EASY-II is designed as a functional replacement for the previous European Activation System, EASY-2010. It includes many new features and enhancements, but also benefits already from the feedback from extensive validation and verification activities performed with its predecessor.

The DARPA High-Performance Polymer Program. Volume 2. Appendix--Selected Presentation Material From the Program Review Held on 14-15 January 1992

DTIC Science & Technology

1992-09-01

BLOCK COPOLYMERS 9:45 M. DRUY (FMI): PROCESSING 9:59 F.E. KARASZ: WRAP UP ll-A-3 1- c-i ) ’a I CLo CL- ___ __ LU. cnl .Z Osc__ LU I-M Cm ~ 0 0I 01 U...FACULTY ASSOCIATES: Prof. Lahti; Druy (FMI) * PPV AND DERIVATIVES; COPOLYMERS AND BLENDS * PROCESSING (COUPLE TO NLO) II-A-7 NON LINEAR OPTICAL PROPERTIES I...PENNSYLVANIA I "POLYMERS BY NON-REDOX PROCESSES : SYNTHESIS, PHYSICAL STUDIES I AND APPLICATION" I CONTRACT NO.: N00014-86-K-0766 SEPTEMBER 16, 1986 - OCTOBER

Rheological of chocolate-flavored, reduced-calories coating as a function of conching process.

PubMed

Medina-Torres, Luis; Sanchez-Olivares, Guadalupe; Nuñez-Ramirez, Diola Marina; Moreno, Leonardo; Calderas, Fausto

2014-07-01

Continuous flow and linear viscoelasticity rheology of chocolate coating is studied in this work using fat substitute gums (xanthan, GX). An alternative conching process, using a Rotor-Estator (RE) type impeller, is proposed. The objective is to obtain a chocolate coating material with improved flow properties. Characterization of the final material through particle size distribution (PSD), differential scanning calorimetry (DSC) and proximal analysis is reported. Particle size distribution of the final material showed less polydispersity and therefore, greater homogeneity; fusion points were also generated at around 20 °C assuming crystal type I (β'2) and II (α). Moreover, the final material exhibited crossover points (higher structure material), whereas the commercial brand chocolate used for comparison did not. The best conditions to produce the coating were maturing of 36 h and 35 °C, showing crossover points around 76 Pa and a 0.505 solids particle dispersion (average particle diameter of 0.364 μm), and a fusion point at 20.04 °C with a ΔHf of 1.40 (J/g). The results indicate that xanthan gum is a good substitute for cocoa butter and provides stability to the final product.

Development of CASI (Computer Aided Speckle Interferometry) and LSS (Laser Speckle Sensor) with Application to Material Response under High Strain Rate, High Temperature, Vibration and Fatigue

DTIC Science & Technology

1991-02-10

25. 1"S. revised mcp recerved Apnil 10, 19W, thnnsmte into a VAX- 11� computer. Fringf_ spacing * acceped for puablI Al 126. 1990 This paPetis a...W.Il.Peters, W.F.llanson mtid S.WI.-MN1il, "Detcrintation of dis. placements using an improved (digit al rorrela Ii’’i ii’’ h. . 111 aad Vision Y*omput ing...experiimental mcchaniics", Experiment al Mechianics, Vol.25, No.3, pp 232-.1-1 (1985). 5.~ A.Rosenfeld and A.C.Kak, Digital Pict nre processing, Vol 1

Synthesis and Performance of LiFe1-xMnxPO4 in Lithium-ion Battery

NASA Astrophysics Data System (ADS)

Bazzi, Khadije; Nazri, Maryam; Vaishnava, Prem; Naik, Vaman; Nazri, Gholam-Abbas; Naik, Ratna

2013-03-01

Olivine-type lithium transition metal phosphates (i.e. LiFePO4) have been intensively investigated as promising electrode materials for rechargeable lithium-ion batteries. There have been attempts to improve energy density and voltage quality of phosphate based electrode. In this study, we have partially substituted FeII/FeIII redox center with MnII/MnIII in LiFePO4 that provides over 600 mV higher voltage. We prepared various compositions of LiFe1-xMnxPO4 (x =0, 0.2, 0.4, 0.6, 0.8 and 1) between the two end members (LiFePO4 - LiMnPO4) . Due to intrinsic low electronic conductivity of lithium transition metal phosphates, we coat these materials with a uniform conductive carbon through a unique sol-gel process developed in our laboratory. In addition, we made a composite of the carbon coated phosphate with carbon nano-tubes to develop a highly conductive matrix electrode. We report the materials structure, morphology, electrical conductivity and electrochemical performances of LiFe1-xMnxPO4 using XRD, Raman spectroscopy, SEM, TEM, XPS, electrical conductivity and galvanostatic charge/discharge measurements.

Investigation to reduce students’ misconception in energy material

NASA Astrophysics Data System (ADS)

Wijayanti, M. D.; Raharjo, S. B.; Saputro, S.; Mulyani, S.

2018-05-01

The purpose of this study is to analyse the misconception of Teacher Candidate of Elementary School (PGSD) on energy materials. This research is expected to be a common misconception in teaching and learning activities. One solution to overcome misconceptions is by investigation. This study uses qualitative research. The subject of this research needs 35 students. Data analysis is done by comparing the observation and test results. The results of this study is the result of students learning outcomes through cycle I and cycle II. The first cycle is due to overweight misconceptions of 18.57% and cycle II of 35.71%. Misconception can be caused by a procedural negligence. Students of PGSD Are examined to show if they understood in a simple movement problem which needs a neverse proportionality concept, to find out a way to prevent misunderstanding. The examination may consist of the question of energy materials by different representation for each student. The conceptual knowledge of the students show incorrectness because they feel confused of existing knowledge they got in their daily lives. It can cause scientific misunderstanding. The declining in student misconceptions is caused by investigation process. Search and data collection are helpful in improving their thinking skills.

Time-dependent constitutive modeling of drive belts—II. The effect of the shape of material retardation spectrum on the strain accumulation process

NASA Astrophysics Data System (ADS)

Zupančič, B.; Emri, I.

2009-11-01

This is the second paper in the series addressing the constitutive modeling of dynamically loaded elastomeric products such as power transmission belts. During the normal operation of such belts certain segments of the belt structure are loaded via tooth-like cyclical loading. When the time-dependent properties of the elastomeric material “match” the time-scale of the dynamic loading a strain accumulation (incrementation) process occurs. It was shown that the location of a critical rotation speed strongly depends on the distribution (shape) of the retardation spectrum, whereas the magnitude of the accumulated strain is governed by the strength of the corresponding spectrum lines. These interrelations are extremely non-linear. The strain accumulation process is most intensive at the beginning of the drive belt operation, and is less intensive for longer belts. The strain accumulation process is governed by the spectrum lines that are positioned within a certain region, which we call the Strain Accumulation Window (SAW). An SAW is always located to the right of the spectrum line, L i , at log ( ω λ i )=0, where ω is the operational angular velocity. The width of the SAW depends on the width of the material spectrum. Based on the following analysis a new designing criterion is proposed for use in engineering applications for selecting a proper material for general drive-belt operations.

IEEE Photovoltaic Specialists Conference, 20th, Las Vegas, NV, Sept. 26-30, 1988, Conference Record. Volumes 1 & 2

NASA Astrophysics Data System (ADS)

Various papers on photovoltaics are presented. The general topics considered include: amorphous materials and cells; amorphous silicon-based solar cells and modules; amorphous silicon-based materials and processes; amorphous materials characterization; amorphous silicon; high-efficiency single crystal solar cells; multijunction and heterojunction cells; high-efficiency III-V cells; modeling and characterization of high-efficiency cells; LIPS flight experience; space mission requirements and technology; advanced space solar cell technology; space environmental effects and modeling; space solar cell and array technology; terrestrial systems and array technology; terrestrial utility and stand-alone applications and testing; terrestrial concentrator and storage technology; terrestrial stand-alone systems applications; terrestrial systems test and evaluation; terrestrial flatplate and concentrator technology; use of polycrystalline materials; polycrystalline II-VI compound solar cells; analysis of and fabrication procedures for compound solar cells.

Process for dezincing galvanized steel

DOEpatents

Morgan, William A.; Dudek, Frederick J.; Daniels, Edward J.

1998-01-01

A process for removing zinc from galvanized steel. The galvanized steel is immersed in an electrolyte containing at least about 15% by weight of sodium or potassium hydroxide and having a temperature of at least about 75.degree. C. and the zinc is galvanically corroded from the surface of the galvanized steel. The material serving as the cathode is principally a material having a standard electrode potential which is intermediate of the standard electrode potentials of zinc and cadmium in the electrochemical series. The corrosion rate may be accelerated by (i) increasing the number density of corrosion sites in the galvanized steel by mechanically abrading or deforming the galvanized steel, (ii) heating the galvanized steel to form an alloy of zinc on the surface of the galvanized steel, (iii) mixing the galvanized steel with a material having a standard electrode potential which is intermediate of the standard electrode potentials of zinc and cadmium in the electrochemical series, or (iv) moving the galvanized steel relative to itself and to the electrolyte while immersed in the electrolyte.

Platinum Acetylide Two-Photon Chromophores (Preprint)

DTIC Science & Technology

2007-04-01

nonlinear photonics,6-s microfabrication,9,10 fluorescence imaging, II and photodynamic therapy.12Instantaneous absorption of two lower energy photons...results in initiation of the same photophysical processes as one-photon absorption (lP A) of one high- energy photon. This is advantageous for two...reasons. The first is that because of the use of a lower energy photon a material will be guarded from ionization effects from multiphoton absorption in

Modelling the drying of three-dimensional pulp moulded structures. Part II, Drying data obtained from flat panels using virgin and recycled paper fibre

Treesearch

John F. Hunt; Margit Tamasy-Bano; Heike Nyist

1999-01-01

A three-dimensional structural panel, called FPL Spaceboard, was developed at the USDA Forest Products Laboratory. Spaceboard panels have been formed using a variety of fibrous materials using either a wet- or dry-forming process. Geometrically, the panel departs from the traditional two-dimensional flat panel by integrally forming an array of perpendicular ribs and...

Direct Fabrication of a-Si:H Thin Film Transistor Arrays on Plastic and Metal Foils for Flexible Displays

DTIC Science & Technology

2008-12-01

TFTs ) arrays for high information content active matrix flexible displays for Army applications. For all flexible substrates a manufacturable...impermeable flexible substrate systems “display-ready” materials and handling protocols, (ii) high performance TFT devices and circuits fabricated...processes for integration with the flexible TFT arrays. Approaches and solution to address each of these major challenges are described in the

Adhesive bonded structural repair. II - Surface preparation procedures, tools, equipment and facilities

NASA Astrophysics Data System (ADS)

Wegman, Raymond F.; Tullos, Thomas R.

1993-10-01

A development status report is presented on the surface preparation procedures, tools, equipment, and facilities used in adhesively-bonded repair of aerospace and similar high-performance structures. These methods extend to both metallic and polymeric surfaces. Attention is given to the phos-anodize containment system, paint removal processes, tools for cutting composite prepreg and fabric materials, autoclaves, curing ovens, vacuum bagging, and controlled atmospheres.

Baseline tests for arc melter vitrification of INEL buried wastes. Volume II: Baseline test data appendices

DOE Office of Scientific and Technical Information (OSTI.GOV)

Oden, L.L.; O`Conner, W.K.; Turner, P.C.

1993-11-19

This report presents field results and raw data from the Buried Waste Integrated Demonstration (BWID) Arc Melter Vitrification Project Phase 1 baseline test series conducted by the Idaho National Engineering Laboratory (INEL) in cooperation with the U.S. Bureau of Mines (USBM). The baseline test series was conducted using the electric arc melter facility at the USBM Albany Research Center in Albany, Oregon. Five different surrogate waste feed mixtures were tested that simulated thermally-oxidized, buried, TRU-contaminated, mixed wastes and soils present at the INEL. The USBM Arc Furnace Integrated Waste Processing Test Facility includes a continuous feed system, the arc meltingmore » furnace, an offgas control system, and utilities. The melter is a sealed, 3-phase alternating current (ac) furnace approximately 2 m high and 1.3 m wide. The furnace has a capacity of 1 metric ton of steel and can process as much as 1,500 lb/h of soil-type waste materials. The surrogate feed materials included five mixtures designed to simulate incinerated TRU-contaminated buried waste materials mixed with INEL soil. Process samples, melter system operations data and offgas composition data were obtained during the baseline tests to evaluate the melter performance and meet test objectives. Samples and data gathered during this program included (a) automatically and manually logged melter systems operations data, (b) process samples of slag, metal and fume solids, and (c) offgas composition, temperature, velocity, flowrate, moisture content, particulate loading and metals content. This report consists of 2 volumes: Volume I summarizes the baseline test operations. It includes an executive summary, system and facility description, review of the surrogate waste mixtures, and a description of the baseline test activities, measurements, and sample collection. Volume II contains the raw test data and sample analyses from samples collected during the baseline tests.« less

Non-Equilibrium Phenomena in High Power Beam Materials Processing

NASA Astrophysics Data System (ADS)

Tosto, Sebastiano

2004-03-01

The paper concerns some aspects of non-equilibrium materials processing with high power beams. Three examples show that the formation of metastable phases plays a crucial role to understand the effects of beam-matter interaction: (i) modeling of pulsed laser induced thermal sputtering; (ii) formation of metastable phases during solidification of the melt pool; (i) possibility of carrying out heat treatments by low power irradiation ``in situ''. The case (i) deals with surface evaporation and boiling processes in presence of superheating. A computer simulation model of thermal sputtering by vapor bubble nucleation in molten phase shows that non-equilibrium processing enables the rise of large surface temperature gradients in the boiling layer and the possibility of sub-surface temperature maximum. The case (ii) concerns the heterogeneous welding of Cu and AISI 304L stainless steel plates by electron beam irradiation. Microstructural investigation of the molten zone has shown that dwell times of the order of 10-1-10-3 s, consistent with moderate cooling rates in the range 10^3-10^5 K/s, entail the formation of metastable Cu-Fe phases. The case (iii) concerns electron beam welding and post-welding treatments of 2219 Al base alloy. Electron microscopy and positron annihilation have explained why post-weld heat transients induced by low power irradiation of specimens in the as welded condition enable ageing effects usually expected after some hours of treatment in furnace. The problem of microstructural instability is particularly significant for a correct design of components manufactured with high power beam technologies and subjected to severe acceptance standards to ensure advanced performances during service life.

Environmental impact of rejected materials generated in organic fraction of municipal solid waste anaerobic digestion plants: Comparison of wet and dry process layout.

PubMed

Colazo, Ana-Belén; Sánchez, Antoni; Font, Xavier; Colón, Joan

2015-09-01

Anaerobic digestion of source separated organic fraction of municipal solid waste is an increasing waste valorization alternative instead of incineration or landfilling of untreated biodegradable wastes. Nevertheless, a significant portion of biodegradable wastes entering the plant is lost in pre-treatments and post-treatments of anaerobic digestion facilities together with other improper materials such as plastics, paper, textile materials and metals. The rejected materials lost in these stages have two main implications: (i) less organic material enters to digesters and, as a consequence, there is a loss of biogas production and (ii) the rejected materials end up in landfills or incinerators contributing to environmental impacts such as global warming or eutrophication. The main goals of this study are (i) to estimate potential losses of biogas in the rejected solid materials generated during the pre- and post-treatments of two full-scale anaerobic digestion facilities and (ii) to evaluate the environmental burdens associated to the final disposal (landfill or incineration) of these rejected materials by means of Life Cycle Assessment. This study shows that there is a lost of potential biogas production, ranging from 8% to 15%, due to the loss of organic matter during pre-treatment stages in anaerobic digestion facilities. From an environmental point of view, the Life Cycle Assessment shows that the incineration scenario is the most favorable alternative for eight out of nine impact categories compared with the landfill scenario. The studied impact categories are Climate Change, Fossil depletion, Freshwater eutrophication, Marine eutrophication, Ozone depletion, Particulate matter formation, Photochemical oxidant formation, Terrestrial acidification and Water depletion. Copyright © 2015 Elsevier Ltd. All rights reserved.

78 FR 19016 - Importer of Controlled Substances; Notice of Registration; Johnson Matthey, Inc.

Federal Register 2010, 2011, 2012, 2013, 2014

2013-03-28

... Schedule Coca Leaves (9040) II Thebaine (9333) II Opium, raw (9600) II Noroxymorphone (9668) II Poppy Straw Concentrate (9670) II The company plans to import the listed controlled substances as raw materials, to be...

Composting on Mars or the Moon: II. Temperature feedback control with top-wise introduction of waste material and air

NASA Technical Reports Server (NTRS)

Finstein, M. S.; Hogan, J. A.; Sager, J. C.; Cowan, R. M.; Strom, P. F.; Janes, H. W. (Principal Investigator)

1999-01-01

Whereas Earth-based composting reactors that effectively control the process are batch operations with bottom-to-top airflow, in extraterrestrial application both the fresh waste and the air need to be introduced from above. Stabilized compost and used air would exit below. This materials flow pattern permits the addition of waste whenever generated, obviating the need for multiple reactors, and the incorporation of a commode in the lid. Top loading in turn dictates top-down aeration, so that the most actively decomposing material (greatest need for heat removal and O2 replenishment) is first encountered. This novel material and aeration pattern was tested in conjunction with temperature feedback process control. Reactor characteristics were: working, volume, 0.15 m3; charge, 2 kg dry biomass per day (comparable to a 3-4 person self-sufficient bioregenerative habitat); retention time, 7 days. Judging from temperature profile, O2 level, air usage, pressure head loss, moisture, and odor, the system was effectively controlled over a 35-day period. Dry matter disappearance averaged 25% (10-42%). The compost product was substantially, though not completely, stabilized. This demonstrates the compatibility of top-wise introduction of waste and air with temperature feedback process control.

Composting on Mars or the Moon: II. Temperature feedback control with top-wise introduction of waste material and air.

PubMed

Finstein, M S; Hogan, J A; Sager, J C; Cowan, R M; Strom, P F

1999-01-01

Whereas Earth-based composting reactors that effectively control the process are batch operations with bottom-to-top airflow, in extraterrestrial application both the fresh waste and the air need to be introduced from above. Stabilized compost and used air would exit below. This materials flow pattern permits the addition of waste whenever generated, obviating the need for multiple reactors, and the incorporation of a commode in the lid. Top loading in turn dictates top-down aeration, so that the most actively decomposing material (greatest need for heat removal and O2 replenishment) is first encountered. This novel material and aeration pattern was tested in conjunction with temperature feedback process control. Reactor characteristics were: working, volume, 0.15 m3; charge, 2 kg dry biomass per day (comparable to a 3-4 person self-sufficient bioregenerative habitat); retention time, 7 days. Judging from temperature profile, O2 level, air usage, pressure head loss, moisture, and odor, the system was effectively controlled over a 35-day period. Dry matter disappearance averaged 25% (10-42%). The compost product was substantially, though not completely, stabilized. This demonstrates the compatibility of top-wise introduction of waste and air with temperature feedback process control.

Superpave in-situ stress/strain investigation--phase II : vol. II, materials characterization.

DOT National Transportation Integrated Search

2009-05-01

The characterization of materials is an intergral part of the overall effort to validate the Superpave system and to calibrate the performance prdeictionmodels for the environmental conditions observed in the Commonwealth of Pennsylvania.

Stable optical oxygen sensing materials based on click-coupling of fluorinated platinum(II) and palladium(II) porphyrins—A convenient way to eliminate dye migration and leaching

PubMed Central

Koren, Klaus; Borisov, Sergey M.; Klimant, Ingo

2012-01-01

Nucleophilic substitution of the labile para-fluorine atoms of 2,3,4,5,6-pentafluorophenyl groups enables a click-based covalent linkage of an oxygen indicator (platinum(II) or palladium(II) 5,10,15,20-meso-tetrakis-(2,3,4,5,6-pentafluorophenyl)-porphyrin) to the sensor matrix. Copolymers of styrene and pentafluorostyrene are chosen as polymeric materials. Depending on the reaction conditions either soluble sensor materials or cross-linked microparticles are obtained. Additionally, we prepared Ormosil-based sensors with linked indicator, which showed very high sensitivity toward oxygen. The effect of covalent coupling on sensor characteristics, stability and photophysical properties is studied. It is demonstrated that leaching and migration of the dye are eliminated in the new materials but excellent photophysical properties of the indicators are preserved. PMID:23576845

Multifunctional Materials Held in Boston, Massachusetts on November 29- December 1 1989. Materials Research Proceedings. Volume 175

DTIC Science & Technology

1991-02-01

MULTIFUNCTIONAL MATERIALS *MULTIFUNCTIONAL MOLECULAR AND POLYMERIC MATERIALS FOR NONLINEAR OPTICS AND PHOTONICS 79 Paras N. Prasad ENHANCEMENT OF...in solution 121. Only the ortho photo-Fries product can be formed for the polymer as well as for 5 since the para positions in both cases are blocked...fhII11111 Itf 111111111ll1111111II 111 111 , 9 MULTIFUNCTIONAL MOLECULAR AND POLYMERIC MATERIALS FOR NONLINEAR OPTICS AND PHOTONICS PARAS N. PRASAD

An economic analysis of the processing technologies in CDW recycling platforms.

PubMed

Oliveira Neto, Raul; Gastineau, Pascal; Cazacliu, Bogdan Grigore; Le Guen, Lauredan; Paranhos, Régis Sebben; Petter, Carlos Otávio

2017-02-01

This paper proposes an economic analysis of three different types of processing in CDW (construction and demolition waste) recycling platforms, according to the sophistication of the processing technologies (current advanced, advanced and advanced sorting). The methodology that is adopted is in the economic evaluation concept of projects and is classified with a scoping study phase. In these contexts, three levels of CDW processing capabilities for recycling platforms are analyzed (100, 300 and 600 thousand tons per year). This article considers databases obtained from similar projects that have been published in the specialized literature; the data sources are primarily from the European continent. The paper shows that current advanced process has better economic performance, in terms of IRR, related to the other two processes. The IRR associated with advanced and advanced sorting processes could be raised by, (i) higher price of secondary primary material, and/or (ii) higher capacity of platforms, and/or (iii) higher sharing of secondary primary material in the total production. The first two points depend on the market conditions (prices and total quantity of CDW available) and (potential) fiscal or incentive policies. The last one depends on technological progress. Copyright © 2016 Elsevier Ltd. All rights reserved.

Using ICP-OES and SEM-EDX in biosorption studies

PubMed Central

Chojnacka, Katarzyna; Marycz, Krzysztof

2010-01-01

We have compared the analytical results obtained by inductively coupled plasma optical emission spectroscopy (ICP-OES) and by scanning electron microscopy with an energy dispersive X-ray analytical system (SEM-EDX) in order to explore the mechanism of metal ions biosorption by biomass using two independent methods. The marine macroalga Enteromorpha sp. was enriched with Cu(II), Mn(II), Zn(II), and Co(II) ions via biosorption, and the biosorption capacity of alga determined from the solution and biomass composition before and after biosorption process was compared. The first technique was used to analyze the composition of the natural and metal-loaded biomass, and additionally the composition of the solution before and after biosorption. The second technique was used to obtain a picture of the surface of natural and metal ion-loaded macroalgae, to map the elements on the cell wall of dry biomass, and to determine their concentration before and after biosorption. ICP-OES showed a better precision and lower detection limit than EDX, but SEM-EDX gave more information regarding the sample composition of Enteromorpha sp. Both techniques confirmed that biosorption is a surface phenomenon, in which alkali and alkaline earth metal ions were exchanged by metal ions from aqueous solution. Figure The advantages and disadvantages of ICP-OES and SEM-EDX techniques Electronic supplementary material The online version of this article (doi:10.1007/s00604-010-0468-0) contains supplementary material, which is available to authorized users. PMID:21423317

Using ICP-OES and SEM-EDX in biosorption studies.

PubMed

Michalak, Izabela; Chojnacka, Katarzyna; Marycz, Krzysztof

2011-02-01

We have compared the analytical results obtained by inductively coupled plasma optical emission spectroscopy (ICP-OES) and by scanning electron microscopy with an energy dispersive X-ray analytical system (SEM-EDX) in order to explore the mechanism of metal ions biosorption by biomass using two independent methods. The marine macroalga Enteromorpha sp. was enriched with Cu(II), Mn(II), Zn(II), and Co(II) ions via biosorption, and the biosorption capacity of alga determined from the solution and biomass composition before and after biosorption process was compared. The first technique was used to analyze the composition of the natural and metal-loaded biomass, and additionally the composition of the solution before and after biosorption. The second technique was used to obtain a picture of the surface of natural and metal ion-loaded macroalgae, to map the elements on the cell wall of dry biomass, and to determine their concentration before and after biosorption. ICP-OES showed a better precision and lower detection limit than EDX, but SEM-EDX gave more information regarding the sample composition of Enteromorpha sp. Both techniques confirmed that biosorption is a surface phenomenon, in which alkali and alkaline earth metal ions were exchanged by metal ions from aqueous solution.FigureThe advantages and disadvantages of ICP-OES and SEM-EDX techniques ELECTRONIC SUPPLEMENTARY MATERIAL: The online version of this article (doi:10.1007/s00604-010-0468-0) contains supplementary material, which is available to authorized users.

R-process enrichment from a single event in an ancient dwarf galaxy.

PubMed

Ji, Alexander P; Frebel, Anna; Chiti, Anirudh; Simon, Joshua D

2016-03-31

Elements heavier than zinc are synthesized through the rapid (r) and slow (s) neutron-capture processes. The main site of production of the r-process elements (such as europium) has been debated for nearly 60 years. Initial studies of trends in chemical abundances in old Milky Way halo stars suggested that these elements are produced continually, in sites such as core-collapse supernovae. But evidence from the local Universe favours the idea that r-process production occurs mainly during rare events, such as neutron star mergers. The appearance of a plateau of europium abundance in some dwarf spheroidal galaxies has been suggested as evidence for rare r-process enrichment in the early Universe, but only under the assumption that no gas accretes into those dwarf galaxies; gas accretion favours continual r-process enrichment in these systems. Furthermore, the universal r-process pattern has not been cleanly identified in dwarf spheroidals. The smaller, chemically simpler, and more ancient ultrafaint dwarf galaxies assembled shortly after the first stars formed, and are ideal systems with which to study nucleosynthesis events such as the r-process. Reticulum II is one such galaxy. The abundances of non-neutron-capture elements in this galaxy (and others like it) are similar to those in other old stars. Here, we report that seven of the nine brightest stars in Reticulum II, observed with high-resolution spectroscopy, show strong enhancements in heavy neutron-capture elements, with abundances that follow the universal r-process pattern beyond barium. The enhancement seen in this 'r-process galaxy' is two to three orders of magnitude higher than that detected in any other ultrafaint dwarf galaxy. This implies that a single, rare event produced the r-process material in Reticulum II. The r-process yield and event rate are incompatible with the source being ordinary core-collapse supernovae, but consistent with other possible sources, such as neutron star mergers.

Investigation of periodically driven systems by x-ray absorption spectroscopy using asynchronous data collection mode

NASA Astrophysics Data System (ADS)

Singh, H.; Donetsky, D.; Liu, J.; Attenkofer, K.; Cheng, B.; Trelewicz, J. R.; Lubomirsky, I.; Stavitski, E.; Frenkel, A. I.

2018-04-01

We report the development, testing, and demonstration of a setup for modulation excitation spectroscopy experiments at the Inner Shell Spectroscopy beamline of National Synchrotron Light Source - II. A computer algorithm and dedicated software were developed for asynchronous data processing and analysis. We demonstrate the reconstruction of X-ray absorption spectra for different time points within the modulation pulse using a model system. This setup and the software are intended for a broad range of functional materials which exhibit structural and/or electronic responses to the external stimulation, such as catalysts, energy and battery materials, and electromechanical devices.

Novel method to sample very high power CO2 lasers: II Continuing Studies

NASA Astrophysics Data System (ADS)

Eric, John; Seibert, Daniel B., II; Green, Lawrence I.

2005-04-01

For the past 28 years, the Laser Hardened Materials Evaluation Laboratory (LHMEL) at the Wright-Patterson Air Force Base, OH, has worked with CO2 lasers capable of producing continuous energy up to 150 kW. These lasers are used in a number of advanced materials processing applications that require accurate spatial energy measurements of the laser. Conventional non-electronic methods are not satisfactory for determining the spatial energy profile. This paper describes continuing efforts in qualifying the new method in which a continuous, real-time electronic spatial energy profile can be obtained for very high power, (VHP) CO2 lasers.

The Role of Pectin in Pb Binding by Carrot Peel Biosorbents: Isoterm Adsorption Study

NASA Astrophysics Data System (ADS)

Hastuti, B.; Totiana, F.; Winiasih, R.

2018-04-01

Cheaply and abundantly biosorption available materials such as carrot peels can be a cost-efficient method for removing heavy metals from wastewater. To investigate the role pectin plays in metal binding by carrot peels, commerce pectin was compared. FTIR spectra confirmed the presence of carboxyl and hydroxyl groups in commerce pectin and carrot pectin. Isoterm experiments showed that all materials could remove Pb (II) ion. All of materials binding Pb (II) follow Freundlich models adsorption. The commerce pectin bindsPb (II) by involving energy 16.6 KJ/mole whereas pectin from carrot peel involves energy 21.09 KJ/mole. It indicates that commerce pectin binds the Pb (II) by physics adsorption whereas pectin from carrot peel by physics and chemical adsorption.

Interlaminar shear fracture toughness and fatigue thresholds for composite materials

NASA Technical Reports Server (NTRS)

Obrien, T. Kevin; Murri, Gretchen B.; Salpekar, Satish A.

1987-01-01

Static and cyclic end notched flexure tests were conducted on a graphite epoxy, a glass epoxy, and graphite thermoplastic to determine their interlaminar shear fracture toughness and fatigue thresholds for delamination in terms of limiting values of the mode II strain energy release rate, G-II, for delamination growth. The influence of precracking and data reduction schemes are discussed. Finite element analysis indicated that the beam theory calculation for G-II with the transverse shear contribution included was reasonably accurate over the entire range of crack lengths. Cyclic loading significantly reduced the critical G-II for delamination. A threshold value of the maximum cyclic G-II below which no delamination occurred after one million cycles was identified for each material. Also, residual static toughness tests were conducted on glass epoxy specimens that had undergone one million cycles without delamination. A linear mixed-mode delamination criteria was used to characterize the static toughness of several composite materials; however, a total G threshold criterion appears to characterize the fatigue delamination durability of composite materials with a wide range of static toughness.

Evaluation of five CAD/CAM materials by microstructural characterization and mechanical tests: a comparative in vitro study.

PubMed

Sonmez, Nesrin; Gultekin, Pinar; Turp, Volkan; Akgungor, Gokhan; Sen, Deniz; Mijiritsky, Eitan

2018-01-08

Polymer infiltrated ceramics and nano-ceramic resins are the new restorative materials which have been developed in order to enhance the adverse properties of glass-matrix ceramics and resin composites. The aim of the present in vitro study was to evaluate the characteristics of various CAD/CAM materials through mechanical, microstructural, and SEM analysis. Five test groups (n = 22) were formed by using the indicated CAD/CAM blocks: VITA Enamic (VITA Zahnfabrik), Lava Ultimate (3 M ESPE), IPS e.max CAD (Ivoclar Vivadent), IPS Empress CAD (Ivoclar Vivadent), and VITA Mark II (VITA Zahnfabrik). Two specimens from each test group were used for XRD and EDS analysis. Remaining samples were divided into two subgroups (n = 10). One subgroup specimens were thermocycled (5 °C to 55 °C, 30s, 10,000 cycles) whereas the other were not. All of the specimens were evaluated in terms of flexural strength, Vickers hardness, and fracture toughness. Results were statistically analyzed using two-way ANOVA, one-way ANOVA, Tukey's HSD, and Student's t tests (α = .05). Fractured specimens were evaluated using SEM. The highest Vickers microhardness value was found for VITA Mark II (p < .001), however flexural strength and fracture toughness results were lowest conversely (p < .05). IPS e.max CAD was found to have the highest flexural strength (p < .001). Fracture toughness of IPS e.max CAD was also higher than other tested block materials (p < .001). Lava Ultimate and VITA Enamic's mechanical properties were affected negatively from thermocycling (p < .05). Microhardness, flexural strength, and fracture toughness values of Lava Ultimate and VITA Enamic were found to be similar to VITA Mark II and IPS Empress CAD groups. It should be realised that simulated aging process seem to affect ceramic-polymer composite materials more significantly than glass ceramics.

Tribochemical Competition within a MoS2/Ti Dry Lubricated Macroscale Contact in Ultrahigh Vacuum: A Time-of-Flight Secondary Ion Mass Spectrometry Investigation.

PubMed

Colas, Guillaume; Saulot, Aurélien; Philippon, David; Berthier, Yves; Léonard, Didier

2018-06-13

Controlling and predicting the tribological behavior of dry lubricants is a necessity to ensure low friction, long life, and low particle generation. Understanding the tribochemistry of the materials as a function of the environment is of primary interest as synergistic effects exist between the mechanics, the physicochemistry, and the thermodynamics within a contact. However, in most studies the role of the coating internal contaminants in the process is often discarded to the benefit of a more common approach in which the performances of the materials are compared as a function of different atmospheric pressure environments. The study focuses on the understanding of the tribochemical processes occurring between the materials and their internal contaminants inside an AISI440C contact lubricated by a MoS 2 /Ti coating. Time-of-flight secondary ion mass spectrometry is used to study at the molecular level, the material before and after friction. Friction tests with different durations are performed in ultrahigh vacuum at the macroscale to stay relevant to the real application (space). The adsorption/desorption of gaseous species during friction is monitored by mass spectrometry to ensure reliable study of the tribochemical processes inside the contact. The study shows that a competition exists between the Ti- and MoS 2 -based materials to create the appropriate lubricating materials via (i) recrystallization of MoS 2 materials with creation of a MoS x O y material via reactions with internal contaminants (presumably H 2 O), (ii) reaction of Ti-based materials with internal contaminants (mostly H 2 O and N 2 ). The biphasic material created is highly similar to the one created in both humid air and dry N 2 environments and providing low friction and low particle generation. However, the process is incomplete. The study thus brings insight into the possibility of controlling friction via a rational inclusion of reactants in a form of contaminants to control the tribochemical processes governing the low friction and long life.

Tensions between materials and environmental quality.

PubMed

Carpenter, R A

1976-02-20

The tensions between availability of materials and quality of the environment will increase with economic growth and the appreciation of environmental values. These tensions can be relieved to an extent by internalizing the costs of environmental protection so that they are reflected in the price of materials. Economic incentives and disincentives, such as effluent fees, are receiving renewed attention (5, pp. 49-51). In addition, government regulation to protect the environment will, perhaps arbitrarily, affect the availability and use of materials. The report, Man, Materials, and Environment (5, p. 25), concluded that: A national materials policy should be based upon the principle that calculations of benefits and costs associated with the extraction, transport, processing, use, and disposal of materials should take full account of the value of common property resources and of any change in the value of common properties resulting from the impact of materials on the environment; and should support the principle that those responsible for impairment of the environment should bear the costs of damage or repair. These principles should become a commonplace element of property rights, legislation, and administrative practice at all levels of government. The difficulty of measuring benefits and costs should not delay adoption of these principles but suggests the need for continuous observation and experimentation. Environmental protection regulations will result in: (i) increased costs for many materials; (ii) disruptive changes in use of materials, due to environmental characteristics and revised cost effectiveness calculations; (iii) restrictions on the siting of processing and manufacturing installations; (iv) preemption of access and surface rights to some mineral bearing lands, particularly those that are federally controlled; (v) diversion of capital from new production facilities; and (vi) frustrating delays in decisions, such as those affecting leasing and plant siting. In return for these generally undesirable disruptions in the continued development and supply of materials, society will obtain: (i) improved quality of air and water; (ii) long-term protection of the natural ecosystems of which man is a part; (iii) more efficient allocation of natural resources on the basis of more accurate and complete accounting of costs; (iv) improved human health through decreased contamination of the environment with toxic substances; and (v) conservation of materials through a closing of the production, use, and disposal cycle. Ingenuity and a more complete understanding of the parts and interactions of the energy, materials, and environment system can do much to reduce the tensions in these conflicts and bring about equitable trade-offs among societal goals.

75 FR 32505 - Importer of Controlled Substances; Notice of Registration

Federal Register 2010, 2011, 2012, 2013, 2014

2010-06-08

... 55858), Johnson Matthey, Inc., Pharmaceutical Materials, 2003 Nolte Drive, West Deptford, New Jersey... Phenylacetone (8501) II Coca Leaves (9040) II Thebaine (9333) II Opium, raw (9600) II Noroxymorphone (9668) II Poppy Straw Concentrate (9670) II The company plans to import the listed controlled substances as raw...

Investigation and Control of "Sphere-Like" Buckminsterfullerene C60 and "Disk-Like" Copper(II) Phthalocyanine

NASA Astrophysics Data System (ADS)

McAfee, Terry Richard

Due to the growing global need for cheap, flexible, and portable electronics, numerous research groups from mechanical and electrical engineering, material science, chemistry, and physics have increasingly turned to organic electronics research over the last ˜5--10 years. Largely, the focus of researchers in this growing field have sought to obtain the next record holding device, allowing a heuristic approach of trial and error to become dominant focus of research rather than a fundamental understanding. Rather than working with the latest high performance organic semiconducting materials and film processing techniques, I have chosen to investigate and control the fundamental self-assembly interactions of organic photovoltaic thin films using simplified systems. Specifically, I focus on organic photovoltaic research using two of the oldest and well studies semiconducting materials, namely "sphere-like" electron donor material Buckminsterfullerene C60 and "disklike" electron acceptor material Copper(II) Phthalocyanine. I manufactured samples using the well-known technique of physical vapor deposition using a high vacuum chamber that I designed and built to accommodate my need of precise material deposition control, with codeposition capability. Films were characterized using microscopy and spectroscopy techniques locally at NCSU, including Atomic Force Microscopy, scanning tunneling microscopy, X-ray photoelectron spectroscopy, and Ultraviolet-visible spectroscopy, as well as at National Laboratory based synchrotron x-ray techniques, including Carbon and Nitrogen k-edge Total Electron Yield and Transmission Near Edge X-ray absorption fine structure spectroscopy, Carbon k-edge Resonant Soft x-ray Microscopy, Resonant Soft x-ray reflectivity, and Grazing Incidence Wide-Angle X-ray scattering.

Biochar prepared from castor oil cake at different temperatures: A voltammetric study applied for Pb(2+), Cd(2+) and Cu(2+) ions preconcentration.

PubMed

Kalinke, Cristiane; Mangrich, Antonio Sálvio; Marcolino-Junior, Luiz H; Bergamini, Márcio F

2016-11-15

Biochar is a carbonaceous material similar produced by pyrolysis of biomass under oxygen-limited conditions. Pyrolysis temperature is an important parameter that can alters biochar characteristics (e.g. surface area, pore size distribution and surface functional groups) and affects it efficacy for adsorption of several probes. In this work, biochar samples have been prepared from castor oil cake using different temperatures of pyrolysis (200-600°C). For the first time, a voltammetric procedure based on carbon paste modified electrode (CPME) was used to investigate the effect of temperature of pyrolysis on the adsorptive characteristics of biochar for Pb(II), Cd(II) and Cu(II) ions. Besides the electrochemical techniques, several characterizations have been performed to evaluate the physicochemical properties of biochar in function of the increase of the pyrolysis temperature. Results suggest that biochar pyrolized at 400°C (BC400) showed a better potential for ions adsorption. The CPME modified with BC400 showed better relative current signal with adsorption affinity: Pb(II)>Cd(II)>Cu(II). Kinetic studies revealed that the pseudo-second order model describes more accurately the adsorption process suggesting that the surface reactions control the adsorption rate. Values found for amount adsorbed were 15.94±0.09; 4.29±0.13 and 2.38±0.39μgg(-1) for Pb(II), Cd(II) and Cu(II) ions, respectively. Copyright © 2016 Elsevier B.V. All rights reserved.

Effect of Cu(II), Cd(II) and Zn(II) on Pb(II) biosorption by algae Gelidium-derived materials.

PubMed

Vilar, Vítor J P; Botelho, Cidália M S; Boaventura, Rui A R

2008-06-15

Biosorption of Pb(II), Cu(II), Cd(II) and Zn(II) from binary metal solutions onto the algae Gelidium sesquipedale, an algal industrial waste and a waste-based composite material was investigated at pH 5.3, in a batch system. Binary Pb(II)/Cu(II), Pb(II)/Cd(II) and Pb(II)/Zn(II) solutions have been tested. For the same equilibrium concentrations of both metal ions (1 mmol l(-1)), approximately 66, 85 and 86% of the total uptake capacity of the biosorbents is taken by lead ions in the systems Pb(II)/Cu(II), Pb(II)/Cd(II) and Pb(II)/Zn(II), respectively. Two-metal results were fitted to a discrete and a continuous model, showing the inhibition of the primary metal biosorption by the co-cation. The model parameters suggest that Cd(II) and Zn(II) have the same decreasing effect on the Pb(II) uptake capacity. The uptake of Pb(II) was highly sensitive to the presence of Cu(II). From the discrete model it was possible to obtain the Langmuir affinity constant for Pb(II) biosorption. The presence of the co-cations decreases the apparent affinity of Pb(II). The experimental results were successfully fitted by the continuous model, at different pH values, for each biosorbent. The following sequence for the equilibrium affinity constants was found: Pb>Cu>Cd approximately Zn.

Blade system design studies volume II : preliminary blade designs and recommended test matrix.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Griffin, Dayton A.

2004-06-01

As part of the U.S. Department of Energy's Wind Partnerships for Advanced Component Technologies (WindPACT) program, Global Energy Concepts, LLC is performing a Blade System Design Study (BSDS) concerning innovations in materials, processes and structural configurations for application to wind turbine blades in the multi-megawatt range. The BSDS Volume I project report addresses issues and constraints identified to scaling conventional blade designs to the megawatt size range, and evaluated candidate materials, manufacturing and design innovations for overcoming and improving large blade economics. The current report (Volume II), presents additional discussion of materials and manufacturing issues for large blades, including amore » summary of current trends in commercial blade manufacturing. Specifications are then developed to guide the preliminary design of MW-scale blades. Using preliminary design calculations for a 3.0 MW blade, parametric analyses are performed to quantify the potential benefits in stiffness and decreased gravity loading by replacement of a baseline fiberglass spar with carbon-fiberglass hybrid material. Complete preliminary designs are then presented for 3.0 MW and 5.0 MW blades that incorporate fiberglass-to-carbon transitions at mid-span. Based on analysis of these designs, technical issues are identified and discussed. Finally, recommendations are made for composites testing under Part I1 of the BSDS, and the initial planned test matrix for that program is presented.« less

Fe-As sludge stability and effluent quality for a two-stage As-contaminated water treatment with Fe(II) and aeration.

PubMed

Zhuang, J Ming; Hobenshield, Evan; Walsh, Tony

2009-02-01

A two-stage (I and II) lab-scale treatment system has been studied for arsenic removal from water using Fe(II) and lignosulphonates with aeration. In stage I, using an Fe/As mole ratio of 1.5-2.5 at a pH of around 6.5-7.5, the dissolved arsenic can be reduced with Fe(II) oxidation-precipitation from an initial 72 mg L(-1) to < 2 mg L(-1). The generated sludge is entirely recycled to the second tank of stage II. In the first tank of stage II, the water is further treated with the same amount of Fe(II) as that used in stage I, in the presence of lignosulphonates and aeration. The air-oxidization of Fe(II) to Fe(III) is continued for about 30 minutes at a pH of around 7.0-8.0. The water output from the first tank is transferred to the second tank in which mixing under aeration occurs with the sludge recycled from stage I. Accordingly, the dissolved arsenic in the effluent is reduced to < 0.1 mg L(-1). The results show that this two-stage process can save more than 50% of total chemical costs, and reduce the amount of sludge by more than 50%, in comparison with the conventional Fe(III)/lime-treatment process. According to US EPA regulations, the final Fe-As sludge is classified as non-hazardous materials by the Toxicity Characteristic Leaching Procedure. But, the study shows that the instability of Fe-As sludge could be influenced by some factors, such as higher pH levels, a longer water-leaching time and larger water-leaching volume, leading to the liberation of more dissolvable As species. After being treated with Ligmet stabilizer, the Fe-As sludge showed an improved stability under varying pH conditions and large amounts of water leaching. The treated Fe-As sludge is suitable for landfill disposal.

Solid-phase materials for chelating metal ions and methods of making and using same

DOEpatents

Harrup, Mason K.; Wey, John E.; Peterson, Eric S.

2003-06-10

A solid material for recovering metal ions from aqueous streams, and methods of making and using the solid material, are disclosed. The solid material is made by covalently bonding a chelating agent to a silica-based solid, or in-situ condensing ceramic precursors along with the chelating agent to accomplish the covalent bonding. The chelating agent preferably comprises a oxime type chelating head, preferably a salicylaldoxime-type molecule, with an organic tail covalently bonded to the head. The hydrocarbon tail includes a carbon-carbon double bond, which is instrumental in the step of covalently bonding the tail to the silica-based solid or the in-situ condensation. The invented solid material may be contacted directly with aqueous streams containing metal ions, and is selective to ions such as copper (II) even in the presence of such ions as iron (III) and other materials that are present in earthen materials. The solid material with high selectivity to copper may be used to recover copper from mining and plating industry streams, to replace the costly and toxic solvent extraction steps of conventional copper processing.

Functional microporous materials of metal carboxylate: Gas-occlusion properties and catalytic activities

NASA Astrophysics Data System (ADS)

Mori, Wasuke; Sato, Tomohiko; Ohmura, Tesushi; Nozaki Kato, Chika; Takei, Tohru

2005-08-01

Copper(II) terephthalate is the first transition metal complex found capable of adsorbing gases. This complex has opened the new field of adsorbent complex chemistry. It is recognized as the lead complex in the construction of microporous complexes. This specific system has been expanded to a systematic series of derivatives of other isomorphous transition metals, molybdenum(II), ruthenium(II, III), and rhodium(II). These complexes with open frameworks are widely recognized as very useful materials for applications to catalysis, separation at molecular level, and gas storage.

Chemical degradation and morphological instabilities during focused ion beam prototyping of polymers.

PubMed

Orthacker, A; Schmied, R; Chernev, B; Fröch, J E; Winkler, R; Hobisch, J; Trimmel, G; Plank, H

2014-01-28

Focused ion beam processing of low melting materials, such as polymers or biological samples, often leads to chemical and morphological instabilities which prevent the straight-forward application of this versatile direct-write structuring method. In this study the behaviour of different polymer classes under ion beam exposure is investigated using different patterning parameters and strategies with the aim of (i) correlating local temperatures with the polymers' chemistry and its morphological consequences; and (ii) finding a way of processing sensitive polymers with lowest chemical degradation while maintaining structuring times. It is found that during processing of polymers three temperature regimes can be observed: (1) at low temperatures all polymers investigated show stable chemical and morphological behaviour; (2) very high temperatures lead to strong chemical degradation which entails unpredictable morphologies; and (3) in the intermediate temperature regime the behaviour is found to be strongly material dependent. A detailed look reveals that polymers which rather cross-link in the proximity of the beam show stable morphologies in this intermediate regime, while polymers that rather undergo chain scission show tendencies to develop a creeping phase, where material follows the ion beam movement leading to instable and unpredictable morphologies. Finally a simple, alternative patterning strategy is suggested, which allows stable processing conditions with lowest chemical damage even for challenging polymers undergoing chain scission.

Cation-induced coagulation of aquatic plant-derived dissolved organic matter: Investigation by EEM-PARAFAC and FT-IR spectroscopy.

PubMed

Liu, Shasha; Zhu, Yuanrong; Liu, Leizhen; He, Zhongqi; Giesy, John P; Bai, Yingchen; Sun, Fuhong; Wu, Fengchang

2018-03-01

Complexation and coagulation of plant-derived dissolved organic matter (DOM) by metal cations are important biogeochemical processes of organic matter in aquatic systems. Thus, coagulation and fractionation of DOM derived from aquatic plants by Ca(II), Al(III), and Fe(III) ions were investigated. Metal ion-induced removal of DOM was determined by analyzing dissolved organic carbon in supernatants after addition of these metal cations individually. After additions of metal ions, both dissolved and coagulated organic fractions were characterized by use of fluorescence excitation emission matrix-parallel factor (EEM-PARAFAC) analysis and Fourier transform infrared (FT-IR) spectroscopy. Addition of Ca(II), Fe(III) or Al(III) resulted in net removal of aquatic plant-derived DOM. Efficiencies of removal of DOM by Fe(III) or Al(III) were greater than that by Ca(II). However, capacities to remove plant-derived DOM by the three metals were less than which had been previously reported for humic materials. Molecular and structural features of plant-derived DOM fractions in associations with metal cations were characterized by changes in fluorescent components and infrared absorption peaks. Both aromatic and carboxylic-like organic matters could be removed by Ca(II), Al(III) or Fe(III) ions. Whereas organic matters containing amides were preferentially removed by Ca(II), and phenolic materials were selectively removed by Fe(III) or Al(III). These observations indicated that plant-derived DOM might have a long-lasting effect on water quality and organisms due to its poor coagulation with metal cations in aquatic ecosystems. Plant-derived DOM is of different character than natural organic matter and it is not advisable to attempt removal through addition of metal salts during treatment of sewage. Copyright © 2017 Elsevier Ltd. All rights reserved.

Mechanisms of Mn(II) catalytic oxidation on ferrihydrite surfaces and the formation of manganese (oxyhydr)oxides

NASA Astrophysics Data System (ADS)

Lan, Shuai; Wang, Xiaoming; Xiang, Quanjun; Yin, Hui; Tan, Wenfeng; Qiu, Guohong; Liu, Fan; Zhang, Jing; Feng, Xionghan

2017-08-01

Oxidation of Mn(II) is an important process that controls the mobility and bioavailability of Mn, as well as the formation of Mn (oxyhydr)oxides in natural systems. It was found that the surfaces of minerals, such as iron (oxyhydr)oxides, can accelerate Mn(II) oxidation to a certain degree, but the underlying mechanism has not been clearly understood. This study explores the reaction pathways and mechanisms of Mn(II) oxidation on ferrihydrite surfaces at neutral pH, commonly found in natural environments, by comparisons with montmorillonite, amorphous Al(OH)3, goethite, and magnetite using macroscopic experiments and spectroscopic analyses. Results show that when Mn(II) concentrations are below 4 mM, macroscopic Mn(II) adsorption on the three iron (oxyhydr)oxide surfaces conforms well to the Langmuir equation, with ferrihydrite showing the highest adsorption capacity. With Mn(II) concentrations ranging within 6-24 mM, the adsorbed Mn(II) is mainly oxidized into manganite (γ-MnOOH) and/or feitknechtite (β-MnOOH) by dissolved O2, and Mn(II) removal on a unit mass basis in the presence of magnetite is the highest compared with ferrihydrite and goethite. Ferrihydrite, a semiconductor material, shows stronger catalytic ability for Mn(II) oxidation on the same surface area than insulator minerals (i.e., montmorillonite and amorphous Al(OH)3). Additionally, the products of Mn(II) oxidation in the presence of semiconductor iron (oxyhydr)oxides (i.e., ferrihydrite, goethite, or magnetite) at the same Fe/Mn molar ratio include both manganite and a small amount of Mn(IV) minerals, and the Mn average oxidation states (Mn AOSs) of these products follow the order: magnetite > goethite > ferrihydrite. Magnetite and goethite, with relatively smaller SSAs and lower band gap energies, exhibit greater catalysis for Mn(II) oxidation than ferrihydrite at the same Fe/Mn ratio, which goes against the conventional interfacial effect and is related to the electrochemical properties. Thus, the Mn(II) catalytic oxidation by O2 on ferrihydrite surfaces should include an electrochemical pathway, i.e., electron transfer (ET) in the Mn(II)-Conduction Band (CB)Ferrihydrite-O2 complexes, in addition to the conventional two interfacial catalytic pathways, i.e., ET in the Mn(II)-Fe(II, III)-O2 complexes and direct ET in the Mn(II)-O2 complexes. These results reveal new implications for understanding the processes and mechanisms of Mn(II) oxidation on iron (oxyhydr)oxide surfaces and the abiotic formation of Mn (oxyhydr)oxides in surface environments.

NASA's In-Space Manufacturing Project: Materials and Manufacturing Process Development Update

NASA Technical Reports Server (NTRS)

Prater, Tracie; Bean, Quincy; Werkheiser, Niki; Ledbetter, Frank

2017-01-01

The mission of NASA's In-Space Manufacturing (ISM) project is to identify, design, and implement on-demand, sustainable manufacturing solutions for fabrication, maintenance and repair during exploration missions. ISM has undertaken a phased strategy of incrementally increasing manufacturing capabilities to achieve this goal. The ISM project began with the development of the first 3D printer for the International Space Station. To date, the printer has completed two phases of flight operations. Results from phase I specimens indicated some differences in material properties between ground-processed and ISS-processed specimens, but results of follow-on analyses of these parts and a ground-based study with an equivalent printer strongly indicate that this variability is likely attributable to differences in manufacturing process settings between the ground and flight prints rather than microgravity effects on the fused deposition modeling (FDM) process. Analysis of phase II specimens from the 3D Printing in Zero G tech demo, which shed further light on the sources of material variability, will be presented. The ISM project has also developed a materials characterization plan for the Additive Manufacturing Facility, the follow-on commercial multimaterial 3D printing facility developed for ISS by Made in Space. This work will yield a suite of characteristic property values that can inform use of AMF by space system designers. Other project activities include development of an integrated 3D printer and recycler, known as the Refabricator, by Tethers Unlimited, which will be operational on ISS in 2018. The project also recently issued a broad area announcement for a multimaterial fabrication laboratory, which may include in-space manufacturing capabilities for metals, electronics, and polymeric materials, to be deployed on ISS in the 2022 timeframe.

Improving student learning in calculus through applications

NASA Astrophysics Data System (ADS)

Young, C. Y.; Georgiopoulos, M.; Hagen, S. C.; Geiger, C. L.; Dagley-Falls, M. A.; Islas, A. L.; Ramsey, P. J.; Lancey, P. M.; Straney, R. A.; Forde, D. S.; Bradbury, E. E.

2011-07-01

Nationally only 40% of the incoming freshmen Science, Technology, Engineering and Mathematics (STEM) majors are successful in earning a STEM degree. The University of Central Florida (UCF) EXCEL programme is a National Science Foundation funded STEM Talent Expansion Programme whose goal is to increase the number of UCF STEM graduates. One of the key requirements for STEM majors is a strong foundation in Calculus. To improve student learning in calculus, the EXCEL programme developed two special courses at the freshman level called Applications of Calculus I (Apps I) and Applications of Calculus II (Apps II). Apps I and II are one-credit classes that are co-requisites for Calculus I and II. These classes are teams taught by science and engineering professors whose goal is to demonstrate to students where the calculus topics they are learning appear in upper level science and engineering classes as well as how faculty use calculus in their STEM research programmes. This article outlines the process used in producing the educational materials for the Apps I and II courses, and it also discusses the assessment results pertaining to this specific EXCEL activity. Pre- and post-tests conducted with experimental and control groups indicate significant improvement in student learning in Calculus II as a direct result of the application courses.

Constituting fully integrated visual analysis system for Cu(II) on TiO₂/cellulose paper.

PubMed

Li, Shun-Xing; Lin, Xiaofeng; Zheng, Feng-Ying; Liang, Wenjie; Zhong, Yanxue; Cai, Jiabai

2014-07-15

As a cheap and abundant porous material, cellulose filter paper was used to immobilize nano-TiO2 and denoted as TiO2/cellulose paper (TCP). With high adsorption capacity for Cu(II) (more than 1.65 mg), TCP was used as an adsorbent, photocatalyst, and colorimetric sensor at the same time. Under the optimum adsorption conditions, i.e., pH 6.5 and 25 °C, the adsorption ratio of Cu(II) was higher than 96.1%. Humic substances from the matrix could be enriched onto TCP but the interference of their colors on colorimetric detection could be eliminated by the photodegradation. In the presence of hydroxylamine, neocuproine, as a selective indicator, was added onto TCP, and a visual color change from white to orange was generated. The concentration of Cu(II) was quantified by the color intensity images using image processing software. This fully integrated visual analysis system was successfully applied for the detection of Cu(II) in 10.0 L of drinking water and seawater with a preconcentration factor of 10(4). The log-linear calibration curve for Cu(II) was in the range of 0.5-50.0 μg L(-1) with a determination coefficient (R(2)) of 0.985 and its detection limit was 0.073 μg L(-1).

Sintering, properties and fabrication of Si3N4 + Y2O3 based ceramics

NASA Technical Reports Server (NTRS)

Quackenbush, C. L.; Smith, J. T.; Neil, J. T.; French, K. W.

1983-01-01

Pure silicon nitride shows a remarkable resistance to sintering without the use of densification additives. The present investigation is concerned with results which show the effect of chemical content on sinterability, taking into account the composition, raw material impurities, and processing contaminants. Aspects of sintering are discussed along with strength characteristics, and oxidation relations. Attention is given to phase field I and II materials, phase field III and IV materials, tungsten carbide and oxidation at 600 C, and studies involving shape fabrication by injection molding. It was found that in sintering Si3N4 + Y2O3 an increase in the amount of Y2O3 and, in particular, the addition of Al2O3 enhances the fluidity of the liquid phase.

New porphyrin-polyoxometalate hybrid materials: synthesis, characterization and investigation of catalytic activity in acetylation reactions.

PubMed

Araghi, Mehdi; Mirkhani, Valiollah; Moghadam, Majid; Tangestaninejad, Shahram; Mohammdpoor-Baltork, Iraj

2012-10-14

New hybrid complexes based on covalent interaction between 5,10,15,20-tetrakis(4-aminophenyl)porphyrinatozinc(II) and 5,10,15,20-tetrakis(4-aminophenyl)porphyrinatotin(IV) chloride, and a Lindqvist-type polyoxometalate, Mo(6)O(19)(2-), were prepared. These new porphyrin-polyoxometalate hybrid materials were characterized by (1)H NMR, FT IR and UV-Vis spectroscopic methods and cyclic voltammetry. These spectro- and electrochemical studies provided several spectral data for synthesis of these compounds. Cyclic voltammetry showed the influence of the polyoxometalate on the redox process of the porphyrin ring. The catalytic activity of tin(IV)porphyrin-hexamolybdate hybrid material was investigated in the acetylation of alcohols and phenols with acetic anhydride. The reusability of this catalyst was also investigated.

A History of the Chemical Innovations in Silver-Halide Materials for Color PhotographyII. Color-Forming Development, Part 5. Coupler Innovations after the 1970's—Two-Equivalent Coupler and DIR Coupler

NASA Astrophysics Data System (ADS)

Oishi, Yasushi

After the 1970's on, several manufacturers including Fuji Film, Konica and Agfa-Gevaert participated in innovating color photographic materials by adding their own coupler chemistry to the technological architecture built by Kodak before then. One area of their major advances was development of the couplers having a coupling-off organic group. One of their functional forms was two-equivalent coupler which made the dye-forming process efficient and made the photosensitive layers slim. And another was DIR coupler which improved dramatically the image quality of color negative materials. In this paper a historical overview of these innovations is constructed from the technical documents, mainly patents.

Adsorption of ferrous ions onto montmorillonites

NASA Astrophysics Data System (ADS)

Qin, Dawei; Niu, Xia; Qiao, Min; Liu, Gang; Li, Hongxin; Meng, Zhenxiao

2015-04-01

The adsorption of Fe (II) onto montmorillonites was investigated through initial concentration, contact time, pH and temperature. During the whole adsorption process, the ascorbic acid (Vitamin C) was added as a kind of antioxidant, at the same time, deionized water (after boiling) and nitrogen protection were also used to avoid oxidation. The Fe2+/Fetotal ratio of the iron exists in the Fe-montmorillonites was found more than 95%. Two kinetic models, including pseudo-first-order and pseudo-second-order model, were used to analyze the adsorption process of Fe (II) on montmorillonites. The results of our study showed that adsorption process fitted with pseudo-second-order well. Adsorption isotherms showed that Langmuir model was better than Freundlich model. The thermodynamic parameters ΔG0 and ΔH0 were 3.696 kJ/mol and 6.689 kJ/mol (we just gave the values at 298 K), respectively. The positive values at different temperatures showed that the adsorption process was non-spontaneous and endothermic. The characteristics of materials were determined by X-ray diffraction (XRD), Fourier transform infrared (FT-IR), Surface area and porosity analyzer, Thermogravimetric analysis (TGA), Differential scanning calorimeter (DSC) and Zeta potential distribution.

Communications for Lifelong Success I and II (Tech Prep English I and II). Pilot Test Materials for Pendleton High School, Pendleton, South Carolina. Draft.

ERIC Educational Resources Information Center

Turlington, Anita; And Others

These instructional materials include six supplementary units for Tech Prep English I (grade 9) and six assignments for Tech Prep English II (grade 10). The Tech Prep English I units have these components: unit objectives, introduction, and follow-up exercises. Topics include goal setting, problem solving and decision making, listening and reading…

North Carolina Biomolecular Engineering and Materials Applications Center (NC-BEMAC).

DTIC Science & Technology

1987-12-29

enzyme has been replaced with cobalt(II). A further objective was to investigate Co2 activation by low molecular weight transition metal complexes as...Characterization of Low Molecular Weight Metal Complexes as Potential Models for IBio-Catalytic Processes. A number of transit ion met~~il oom~pi cxe; hive...binding, the enzyme suffered loss of activity during radiation polymerization. When covalent binding was u:sed it was necessary to introduce suitably

Crystallization of Nanocomposite Glasses Made by the SSG Process

DTIC Science & Technology

1993-01-12

thermogravimetric analysis (TGA). The role of glass structure and composition in the thermochemical stability will be discussed. 37 II. EXPERIMENTAL PROCEDLRES The...applications in the materials field. tion and r-plot analysis of this porous nanocomposite showed Because of the nanoscale mixing of inorganic and organic a... nanoparticles in There is a need for substrates with very low relative permit- magnetic recording media can lead to smaller storage units tivitv 1ɛ) in %ery

Manufacturing Methods and Technology Program Plan, CY 1980.

DTIC Science & Technology

1980-09-01

AD-A092 2Ii3 &RMY INDUSTRIAL BASE ENGINEERING ACTIVITY ROCK ISLAND IL FIG 1346 ..ANIJPACTRItd METH4OS AND TECNOLOGY PROGRAM PLAN. CY 1960. (U) %EP 60... innovative solutions. For example, material handling, process tools and inspection systems must be computerized to achieve the desired operating economics and...to decrease expensive direct labor; however, the new systems must also be capable of economic layaway for periods of ten years or more, a situation

Biomimetic and Bioinspired Synthesis of Nanomaterials/Nanostructures.

PubMed

Zan, Guangtao; Wu, Qingsheng

2016-03-16

In recent years, due to its unparalleled advantages, the biomimetic and bioinspired synthesis of nanomaterials/nanostructures has drawn increasing interest and attention. Generally, biomimetic synthesis can be conducted either by mimicking the functions of natural materials/structures or by mimicking the biological processes that organisms employ to produce substances or materials. Biomimetic synthesis is therefore divided here into "functional biomimetic synthesis" and "process biomimetic synthesis". Process biomimetic synthesis is the focus of this review. First, the above two terms are defined and their relationship is discussed. Next different levels of biological processes that can be used for process biomimetic synthesis are compiled. Then the current progress of process biomimetic synthesis is systematically summarized and reviewed from the following five perspectives: i) elementary biomimetic system via biomass templates, ii) high-level biomimetic system via soft/hard-combined films, iii) intelligent biomimetic systems via liquid membranes, iv) living-organism biomimetic systems, and v) macromolecular bioinspired systems. Moreover, for these five biomimetic systems, the synthesis procedures, basic principles, and relationships are discussed, and the challenges that are encountered and directions for further development are considered. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Lu, Q.; Hu, X; Wang, X

Water-insoluble regenerated silk materials are normally produced by increasing the {beta}-sheet content (silk II). In the present study water-insoluble silk films were prepared by controlling the very slow drying of Bombyx mori silk solutions, resulting in the formation of stable films with a predominant silk I instead of silk II structure. Wide angle X-ray scattering indicated that the silk films stabilized by slow drying were mainly composed of silk I rather than silk II, while water- and methanol-annealed silk films had a higher silk II content. The silk films prepared by slow drying had a globule-like structure at the coremore » surrounded by nano-filaments. The core region was composed of silk I and silk II, surrounded by hydrophilic nano-filaments containing random turns and {alpha}-helix secondary structures. The insoluble silk films prepared by slow drying had unique thermal, mechanical and degradative properties. Differential scanning calorimetry results revealed that silk I crystals had stable thermal properties up to 250 C, without crystallization above the T{sub g}, but degraded at lower temperatures than silk II structure. Compared with water- and methanol-annealed films the films prepared by slow drying had better mechanical ductility and were more rapidly enzymatically degraded, reflecting the differences in secondary structure achieved via differences in post processing of the cast silk films. Importantly, the silk I structure, a key intermediate secondary structure for the formation of mechanically robust natural silk fibers, was successfully generated by the present approach of very slow drying, mimicking the natural process. The results also point to a new mode of generating new types of silk biomaterials with enhanced mechanical properties and increased degradation rates, while maintaining water insolubility, along with a low {beta}-sheet content.« less

Executive functions in becoming writing readers and reading writers: note taking and report writing in third and fifth graders.

PubMed

Altemeier, Leah; Jones, Janine; Abbott, Robert D; Berninger, Virginia W

2006-01-01

Results are reported for a study of 2 separate processes of report writing-taking notes while reading source material and composing a report from those notes-and related individual differences in executive functions involved in integrating reading and writing during these writing activities. Third graders (n = 122) and 5th graders (n = 106; overall, 127 girls and 114 boys) completed two reading-writing tasks-read paragraph (mock science text)-write notes and use notes to generate written report, a reading comprehension test, a written expression test, four tests of executive functions (inhibition, verbal fluency, planning, switching attention), and a working memory test. For the read-take notes task, the same combination of variables was best (explained the most variance and each variable added unique variance) for 3rd graders and 5th graders: Wechsler Individual Achievement Test-Second Edition (WIAT-II) Reading Comprehension, Process Assessment of the Learner Test for Reading and Writing (PAL) Copy Task B, WIAT-II Written Expression, and Delis-Kaplan Executive Function System (D-KEFS) Inhibition. For the use notes to write report task, the best combinations of variables depended on grade level: For 3rd graders, WIAT-II Reading Comprehension, WIAT-II Written Expression, D-KEFS Verbal Fluency, and Tower of Hanoi; for 5th graders, WIAT-II Reading Comprehension, D-KEFS Verbal Fluency, WIAT-II Written Expression, and PAL Alphabet Task. These results add to prior research findings that executive functions contribute to the writing development of elementary-grade students and additionally support the hypothesis that executive functions play a role in developing reading-writing connections.

Synthesis and Characteristics of HgCdSe for IR Detection

DTIC Science & Technology

2014-03-11

Photoelectron Spectroscopy Study of Oxide Removal Using Atomic Hydrogen for Large-Area II–VI Material Growth, Journal of Electronic Materials...Workshop on the Physics and Chemistry of II-VI Materials, Chicago IL (October 1-3, 2013) “Use of Atomic Hydrogen to Prepare GaSb(211)B and GaSb(100...Workshop on the Physics and Chemistry of II-VI Materials, Chicago IL (October, 2011) "Xray photoelectron spectroscopy study of oxide removal using

76 FR 35239 - Importer of Controlled Substances; Notice of Application

Federal Register 2010, 2011, 2012, 2013, 2014

2011-06-16

... (9040) II Raw Opium (9600) II Poppy Straw (9650) II Concentrate of Poppy Straw (9670) II The company... narcotic raw material are not appropriate. As noted in a previous notice published in the Federal Register...

75 FR 22844 - Importer of Controlled Substances; Notice of Application

Federal Register 2010, 2011, 2012, 2013, 2014

2010-04-30

... narcotic raw material are not appropriate. As noted in a previous notice published in the Federal Register... Coca Leaves (9040) II Raw Opium (9600) II Poppy Straw (9650) II Concentrate of Poppy Straw (9670) II...

Solution synthesis of germanium nanocrystals

DOEpatents

Gerung, Henry [Albuquerque, NM; Boyle, Timothy J [Kensington, MD; Bunge, Scott D [Cuyahoga Falls, OH

2009-09-22

A method for providing a route for the synthesis of a Ge(0) nanometer-sized material from. A Ge(II) precursor is dissolved in a ligand heated to a temperature, generally between approximately 100.degree. C. and 400.degree. C., sufficient to thermally reduce the Ge(II) to Ge(0), where the ligand is a compound that can bond to the surface of the germanium nanomaterials to subsequently prevent agglomeration of the nanomaterials. The ligand encapsulates the surface of the Ge(0) material to prevent agglomeration. The resulting solution is cooled for handling, with the cooling characteristics useful in controlling the size and size distribution of the Ge(0) materials. The characteristics of the Ge(II) precursor determine whether the Ge(0) materials that result will be nanocrystals or nanowires.

Method of passivating semiconductor surfaces

DOEpatents

Wanlass, M.W.

1990-06-19

A method is described for passivating Group III-V or II-VI semiconductor compound surfaces. The method includes selecting a passivating material having a lattice constant substantially mismatched to the lattice constant of the semiconductor compound. The passivating material is then grown as an ultrathin layer of passivating material on the surface of the Group III-V or II-VI semiconductor compound. The passivating material is grown to a thickness sufficient to maintain a coherent interface between the ultrathin passivating material and the semiconductor compound. In addition, a device formed from such method is also disclosed.

Method of passivating semiconductor surfaces

DOEpatents

Wanlass, Mark W.

1990-01-01

A method of passivating Group III-V or II-VI semiconductor compound surfaces. The method includes selecting a passivating material having a lattice constant substantially mismatched to the lattice constant of the semiconductor compound. The passivating material is then grown as an ultrathin layer of passivating material on the surface of the Group III-V or II-VI semiconductor compound. The passivating material is grown to a thickness sufficient to maintain a coherent interface between the ultrathin passivating material and the semiconductor compound. In addition, a device formed from such method is also disclosed.

30 CFR 784.22 - Geologic information.

Code of Federal Regulations, 2010 CFR

2010-07-01

... occurring; (ii) Chemical analyses identifying those strata that may contain acid- or toxic-forming, or... that the analysis for alkalinity-producing material is unnecessary; and (iii) Chemical analysis of the...; (ii) Chemical analyses for acid- or toxic-forming or alkalinity-producing materials and their content...

Confocal Raman spectroscopy and AFM for evaluation of sidewalls in type II superlattice FPAs

NASA Astrophysics Data System (ADS)

Rotter, T. J.; Busani, T.; Rathi, P.; Jaeckel, F.; Reyes, P. A.; Malloy, K. J.; Ukhanov, A. A.; Plis, E.; Krishna, S.; Jaime-Vasquez, M.; Baril, N. F.; Benson, J. D.; Tenne, D. A.

2015-06-01

We propose to utilize confocal Raman spectroscopy combined with high resolution atomic force microscopy (AFM) for nondestructive characterisation of the sidewalls of etched and passivated small pixel (24 μm×24 μm) focal plane arrays (FPA) fabricated using LW/LWIR InAs/GaSb type-II strained layer superlattice (T2SL) detector material. Special high aspect ratio Si and GaAs AFM probes, with tip length of 13 μm and tip aperture less than 7°, allow characterisation of the sidewall morphology. Confocal microscopy enables imaging of the sidewall profile through optical sectioning. Raman spectra measured on etched T2SL FPA single pixels enable us to quantify the non-uniformity of the mesa delineation process.

Water decontamination via the removal of Pb (II) using a new generation of highly energetic surface nano-material: Co(+2)Mo(+6) LDH.

PubMed

Mostafa, Mohsen S; Bakr, Al-Sayed A; El Naggar, Ahmed M A; Sultan, El-Sayed A

2016-01-01

CoMo(CO3(2-)) layered double hydroxide of a highly energetic surface, as a new LDH consisting of divalent and hexavalent cations (M(+2)/M(+6)-LDH), was prepared by a homogeneous co-precipitation method. The structure and morphology of the prepared material was confirmed by several analytical techniques namely; X-ray diffraction analysis (XRD), X-ray fluorescence (XRF), Fourier transform infra-red (FT-IR) spectroscopy, differential scanning calorimetry and thermal gravimetric analysis (DSC-TGA), N2 adsorption-desorption isotherm and scanning electron microscope (SEM). The highly energetic surface of the prepared LDH was demonstrated via the X-ray photoelectron spectroscopy (XPS). The surface energy is due to the formation of +4 surface charges in the brucite layer between Co(+2) and Mo(+6). The prepared LDH was applied as a novel adsorbent for the removal of Pb (II) from its aqueous solution at different experimental conditions of time, temperature and initial Pb (II) concentrations. The change of the Pb (II) concentrations; due to adsorption, was monitored by atomic absorption spectrophotometer (AAS). The maximum uptake of Pb (II) by the Co Mo LDH was (73.4 mg/g) at 298 K. The Pb (II) adsorption was found to follow Langmuir isotherm and pseudo second order model. The adsorption process was spontaneous and endothermic. The interference of other cations on the removal of the Pb (II) was studied. Na(+) and K(+) were found to increase the adsorption capacity of the Co Mo LDH toward Pb (II) while it was slightly decreased by the presence of Mn(+2) and Cu(+2). The synthesized LDH showed a great degree of recoverability (7 times) while completely conserving its parental morphology and adsorption capacity. The mechanism of the lead ions removal had exhibited more reliability through a surface adsorption by the coordination between the Mo(+6) of the brucite layers and the oxygen atoms of the nitrates counter ions. Copyright © 2015 Elsevier Inc. All rights reserved.

Lateral-access Class II restoration using resin-modified glass-ionomer or silver-cermet cement.

PubMed

Croll, T P

1995-02-01

Direct-access preparation of a carious proximal surface is perhaps the most conservative approach to restoration. Physical properties and handling characteristics of silver amalgam and of resin composite and lack of fluoride ion release make these materials unsuitable for direct buccal- or lingual-access proximal restoration. Insufficient strengths and radiolucency of self-hardening glass-ionomer cements preclude their use for Class II restorations. However, glass-ionomer silver-cermet cement and some resin-modified glass-ionomer materials are proving useful for non-stress-bearing Class II restorations and may have applications in preventive dentistry. This article describes lateral-access Class II restoration with modified glass-ionomer cements. Emphasis is placed on careful handling of materials, maintenance of an ideal operative field, and conservation of tooth structure.

The Type II Supernova Mechanism

NASA Astrophysics Data System (ADS)

Bruenn, Stephen W.

1996-05-01

Supernova 1987A has confirmed the basic core collapse paradigm for Type-II supernovae by the detection of electron antineutrinos in the Kamiokande II and IMB experiments several hours prior to the first optical sighting. Furthermore, the evidence of large-scale mixing and overturn in the debris of SN1987A indicates that hydrodynamic instabilities occurred early on in the evolution of the remnant and have played a crucial role in the explosion mechanism itself. Despite these important clues, and many years of theoretical and numerical investigation of increasing sophistication, the core collapse explosion mechanism is still not well understood. I review the status of the currently favored scenario, which is the transfer of energy from hot material at small radii to cooler material in the region further out behind the stalled shock by a combination of neutrino flow and hydrodynamic instabilities. The nature and role of these hydrodynamic instabilities is explored in detail on the basis of linear perturbation analyses and multidimensional hydrodynamic simulations. Neutrino flow is shown to have an inhibiting effect on convection in the region immediately below the neutrinosphere. Farther in, material is likely to be semiconvective for several hundred milliseconds, but stable thereafter. Convection in the neutrino heated-layer outside the neutrinosphere and below the shock front is found to help but by no means guarantee and explosion. General relativistic effects are shown to be deleterious for neutrino heated explosions. The role of the progenitor structure is discussed on the basis of two distinct but representative examples. Finally, the importance of several neutrino processes not incorporated in current calculations is assessed.

II ZWICKY 23 AND FAMILY: A GROUP IN INTERACTION

DOE Office of Scientific and Technical Information (OSTI.GOV)

Wehner, Elizabeth M. H.; Gallagher III, John S.; Cigan, Phillip J.

2016-09-01

II Zw 23 (UGC 3179) is a luminous (M{sub B}  ∼ −21) nearby compact narrow emission line starburst galaxy with blue optical colors and strong emission lines. We present a photometric and morphological study of II Zw 23 and its interacting companion, KPG103a, using data obtained with the WIYN 3.5 m telescope in combination with a WFPC2 image from the Hubble Space Telescope archives. II Zw 23 has a highly disturbed outer structure with long trails of debris that may be contributing material toward the production of tidal dwarfs. Its central regions appear disky, a structure that is consistent with themore » overall rotation pattern observed in the H α velocity field measured from Densepak observations obtained with WIYN. We find additional evidence for interaction in this system, including the discovery of a new tidal loop extending from an associated dwarf galaxy, which appears to be in the process of disrupting along its orbit. We also present H α equivalent widths and discuss the relative star formation rates across this interacting system.« less

A photofunctional bottom-up bis(dipyrrinato)zinc(II) complex nanosheet

PubMed Central

Sakamoto, Ryota; Hoshiko, Ken; Liu, Qian; Yagi, Toshiki; Nagayama, Tatsuhiro; Kusaka, Shinpei; Tsuchiya, Mizuho; Kitagawa, Yasutaka; Wong, Wai-Yeung; Nishihara, Hiroshi

2015-01-01

Two-dimensional polymeric nanosheets have recently gained much attention, particularly top-down nanosheets such as graphene and metal chalcogenides originating from bulk-layered mother materials. Although molecule-based bottom-up nanosheets manufactured directly from molecular components can exhibit greater structural diversity than top-down nanosheets, the bottom-up nanosheets reported thus far lack useful functionalities. Here we show the design and synthesis of a bottom-up nanosheet featuring a photoactive bis(dipyrrinato)zinc(II) complex motif. A liquid/liquid interfacial synthesis between a three-way dipyrrin ligand and zinc(II) ions results in a multi-layer nanosheet, whereas an air/liquid interfacial reaction produces a single-layer or few-layer nanosheet with domain sizes of >10 μm on one side. The bis(dipyrrinato)zinc(II) metal complex nanosheet is easy to deposit on various substrates using the Langmuir–Schäfer process. The nanosheet deposited on a transparent SnO2 electrode functions as a photoanode in a photoelectric conversion system, and is thus the first photofunctional bottom-up nanosheet. PMID:25831973

Kinetics of methane-ethane gas replacement in clathrate-hydrates studied by time-resolved neutron diffraction and Raman spectroscopy.

PubMed

Murshed, M Mangir; Schmidt, Burkhard C; Kuhs, Werner F

2010-01-14

The kinetics of CH(4)-C(2)H(6) replacement in gas hydrates has been studied by in situ neutron diffraction and Raman spectroscopy. Deuterated ethane structure type I (C(2)H(6) sI) hydrates were transformed in a closed volume into methane-ethane mixed structure type II (CH(4)-C(2)H(6) sII) hydrates at 5 MPa and various temperatures in the vicinity of 0 degrees C while followed by time-resolved neutron powder diffraction on D20 at ILL, Grenoble. The role of available surface area of the sI starting material on the formation kinetics of sII hydrates was studied. Ex situ Raman spectroscopic investigations were carried out to crosscheck the gas composition and the distribution of the gas species over the cages as a function of structure type and compared to the in situ neutron results. Raman micromapping on single hydrate grains showed compositional and structural gradients between the surface and core of the transformed hydrates. Moreover, the observed methane-ethane ratio is very far from the one expected for a formation from a constantly equilibrated gas phase. The results also prove that gas replacement in CH(4)-C(2)H(6) hydrates is a regrowth process involving the nucleation of new crystallites commencing at the surface of the parent C(2)H(6) sI hydrate with a progressively shrinking core of unreacted material. The time-resolved neutron diffraction results clearly indicate an increasing diffusion limitation of the exchange process. This diffusion limitation leads to a progressive slowing down of the exchange reaction and is likely to be responsible for the incomplete exchange of the gases.

Hybrid catechin silica nanoparticle influence on Cu(II) toxicity and morphological lesions in primary neuronal cells.

PubMed

Halevas, E; Nday, C M; Salifoglou, A

2016-10-01

Morphological alterations compromising inter-neuronal connectivity may be directly linked to learning-memory deficits in Central Nervous System neurodegenerative processes. Cu(II)-mediated oxidative stress plays a pivotal role in regulating redox reactions generating reactive oxygen species (ROS) and reactive nitrogen species (RNS), known contributors to Alzheimer's disease (AD) pathology. The antioxidant properties of flavonoid catechin have been well-documented in neurodegenerative processes. However, the impact that catechin encapsulation in nanoparticles may have on neuronal survival and morphological lesions has been poorly demonstrated. To investigate potential effects of nano-encapsulated catechin on neuronal survival and morphological aberrations in primary rat hippocampal neurons, poly(ethyleneglycol) (PEG) and cetyltrimethylammonium bromide (CTAB)-modified silica nanoparticles were synthesized. Catechin was loaded on silica nanoparticles in a concentration-dependent fashion, and release studies were carried out. Further physicochemical characterization of the new nano-materials included elemental analysis, particle size, z-potential, FT-IR, Brunauer-Emmett-Teller (BET), thermogravimetric (TGA), and scanning electron microscopy (SEM) analysis in order to optimize material composition linked to the delivery of loaded catechin in the hippocampal cellular milieu. The findings reveal that, under Cu(II)-induced oxidative stress, the loading ability of the PEGylated/CTAB silica nanoparticles was concentration-dependent, based on their catechin release profile. The overall bio-activity profile of the new hybrid nanoparticles a) denoted their enhanced protective activity against oxidative stress and hippocampal cell survival compared to previously reported quercetin, b) revealed that morphological lesions affecting neuronal integrity can be counterbalanced at high copper concentrations, and c) warrants in-depth perusal of molecular events underlying neuronal function and degeneration, collectively linked to preventive nanotechnology in neurodegeneration. Copyright © 2016 Elsevier Inc. All rights reserved.

Microencapsulation of Drugs: New Cancer Therapies and Improved Drug Delivery Derived from Micro Gravity Research

NASA Technical Reports Server (NTRS)

Morrison, Dennis R.; Haddad, Ruwaida S.

2003-01-01

Experiments on the ISS include encapsulation of several different anti-cancer drugs, magnetic triggering particles, and encapsulation of genetically engineered DNA. Eight experiments, using the MEPS-II apparatus, were conducted to study the limitations of the fluid shear and g-dependent forces. These studies included: 1) formation of anti-tumor microcapsules containing drugs for "Chemoembolization" of vascularized tumors, 2) formation of microcapsules containing a photo-activated drug which can be used for Photo Dynamic Therapy of solid tumors by activation with near infrared light (630 nm), 3) coencapsulation of magnetic trigger particles and anti-tumor drugs, and 4) encapsulation of plasmid DNA. The Microencapsulation Electrostatic Processing System (MEPS-II) is an automated apparatus modified for use in the ISS Express Rack. The process brings together two immiscible liquids, restricting fluid shear to permitting surface tension forces to predominate at the interface of the fluids. Microcapsules were recovered from all 8 experiments and are currently being analyzed for size distribution and drug content. Six NASA Patents have issued from the space research and several more are pending. The preliminary results from the Increment 5 - UF-2 experiments have provided new insight into the best formulations and conditions required to produce microcapsules of different drugs, esp. special capsules containing diagnostic imaging materials and triggered release particles. Co-encapsulation of multiple drugs and Photodynamic Therapy (PDT) drugs has enabled new engineering strategies for production of microcapsules on Earth designed for direct delivery into cancer tissues. Other microcapsules have now been made for treatment of deep tissue infections, clotting disorders, and to provide delivery of genetic engineered materials for potential gene therapy approaches. The MEPS-II apparatus remains in the ISS awaiting microencapsulation experiments to be conducted in micro-g, and returned to Earth for analysis.

High-performance 193-nm photoresist materials based on ROMA polymers: sub-90-nm contact hole application with resist reflow

NASA Astrophysics Data System (ADS)

Joo, Hyun S.; Seo, Dong C.; Kim, Chang M.; Lim, Young T.; Cho, Seong D.; Lee, Jong B.; Song, Ji Y.; Kim, Kyoung M.; Park, Joo H.; Jung, Jae Chang; Shin, Ki S.; Bok, Cheol Kyu; Moon, Seung C.

2004-05-01

There are numerous methods being explored by lithographers to achieve the patterning of sub-90nm contact hole features. Regarding optical impact on contact imaging, various optical extension techniques such as assist features, focus drilling, phase shift masks, and off-axis illumination are being employed to improve the aerial image. One possible option for improving of the process window in contact hole patterning is resist reflow. We have already reported the resist using a ring opened polymer of maleic anhydride unit(ROMA) during the past two years in this conference. It has several good properties such as UV transmittance, PED stability, solubility and storage stability. The resist using ROMA polymer as a matrix resin showed a good lithographic performance at C/H pattern and one of the best characteristics in a ROMA polymer is the property of thermal shrinkage. It has a specific glass transition temperature(Tg) each polymers, so they made a applying of resist reflow technique to print sub-90nm C/H possible. Recently, we have researched about advanced ROMA polymer(ROMA II), which is composed of cycloolefine derivatives with existing ROMA type polymer(ROMA I), for dry etch resistance increasing, high resolution, and good thermal shrinkage property. In this paper, we will present the structure, thermal shrinkage properties, Tg control, material properties for ROMA II polymer and will show characteristics, the lithographic performance for iso and dense C/H applications of the resist using ROMA II polymer. In addition, we will discuss resist reflow data gained at C/H profile of sub-90nm sizes, which has good process window.

Seminar on the Acquisition of Latin American Library Materials (13th, Lawrence, Kansas, June 20-22, 1968). Final Report and Working Papers. Vol. II.

ERIC Educational Resources Information Center

Jordan, Alma; Rovira, Carmen

The eight working papers used as documentation for the Thirteenth Seminar are included in volume II. They are: (1) "Progress Report on the Seminars on the Acquisition of Latin American Library Materials, 1968;" (2) "Significant Acquisitions of Latin American Material by U.S. Libraries, 1967/68;" (3) "A Report of…

77 FR 55503 - Importer of Controlled Substances; Notice of Registration; Cambrex Charles City, Inc.

Federal Register 2010, 2011, 2012, 2013, 2014

2012-09-10

... hearings on applications to import narcotic raw material are not appropriate. 72 FR 3417 (2007). DEA has...-piperidine (8333).. II Phenylacetone (8501) II Opium, raw (9600) II Poppy Straw Concentrate (9670) II The...

78 FR 39337 - Importer of Controlled Substances; Notice Of Registration; Mallinckrodt, LLC.

Federal Register 2010, 2011, 2012, 2013, 2014

2013-07-01

... narcotic raw material are not appropriate, 72 FR 3417 (2007). Regarding Phenylacetone (8501), a basic class... Phenylacetone (8501) II Coca Leaves (9040) II Opium, raw (9600) II Poppy Straw Concentrate (9670) II The company...

New Methods of Simulation of Mn(II) EPR Spectra: Single Crystals, Polycrystalline and Amorphous (Biological) Materials

NASA Astrophysics Data System (ADS)

Misra, Sushil K.

Biological systems exhibit properties of amorphous materials. The Mn(II) ion in amorphous materials is characterized by distributions of spin-Hamiltonian parameters around mean values. It has a certain advantage over other ions, being one of the most abundant elements on the earth. The extent to which living organisms utilize manganese varies from one organism to the other. There is a fairly high concentration of the Mn(II) ion in green plants, which use it in the O2 evolution reaction of photosynthesis (Sauer, 1980). Structure-reactivity relationships in Mn(II)-O2 complexes are given in a review article by Coleman and Taylor (1980). Manganese is a trace requirement in animal nutrition; highly elevated levels of manganese in the diet can be toxic, probably because of an interference with iron homeostasis (Underwood, 1971). On the other hand, animals raised with a dietary deficiency of manganese exhibit severe abnormalities in connective tissue; these problems have been attributed to the obligatory role of Mn(II) in mucopolysaccharide metabolism (Leach, 1971). Mn(II) has been detected unequivocally in living organisms.

Communication Arts: A Tentative Curriculum Guide for English 7-12, Basic, Regular, STS, [Advanced], Junior High Speech A & B, Speech I and II, Drama I and II, and Journalism I and II.

ERIC Educational Resources Information Center

Irving Independent School District, TX.

This guide is intended to be used for instruction in communication skills from the seventh grade through the twelfth. Each section of the guide is identified by grade level and includes instructional objectives, suggestions for introducing and motivating the unit, required material, suggested activities, audiovisual aids, resource materials, and…

Functionalized mesoporous silica supported copper(II) and nickel(II) catalysts for liquid phase oxidation of olefins.

PubMed

Nandi, Mahasweta; Roy, Partha; Uyama, Hiroshi; Bhaumik, Asim

2011-12-14

Highly ordered 2D-hexagonal mesoporous silica has been functionalized with 3-aminopropyltriethoxysilane (3-APTES). This is followed by its condensation with a dialdehyde, 4-methyl-2,6-diformylphenol to produce an immobilized Schiff-base ligand (I). This material is separately treated with methanolic solution of copper(II) chloride and nickel(II) chloride to obtain copper and nickel anchored mesoporous materials, designated as Cu-AMM and Ni-AMM, respectively. The materials have been characterized by Fourier transform infrared (FT-IR) and UV-vis diffuse reflectance (DRS) spectroscopy, powder X-ray diffraction (XRD), transmission electron microscopy (TEM), N(2) adsorption-desorption studies and (13)C CP MAS NMR spectroscopy. The metal-grafted mesoporous materials have been used as catalysts for the efficient and selective epoxidation of alkenes, viz. cyclohexene, trans-stilbene, styrene, α-methyl styrene, cyclooctene and norbornene to their corresponding epoxides in the presence of tert-butyl hydroperoxide (TBHP) as the oxidant under mild liquid phase conditions.

Flexural strength of pure Ti, Ni-Cr and Co-Cr alloys submitted to Nd:YAG laser or TIG welding.

PubMed

Rocha, Rick; Pinheiro, Antônio Luiz Barbosa; Villaverde, Antonio Balbin

2006-01-01

Welding of metals and alloys is important to Dentistry for fabrication of dental prostheses. Several methods of soldering metals and alloys are currently used. The purpose of this study was to assess, using the flexural strength testing, the efficacy of two processes Nd:YAG laser and TIG (tungsten inert gas) for welding of pure Ti, Co-Cr and Ni-Cr alloys. Sixty cylindrical specimens were prepared (20 of each material), bisected and welded using different techniques. Four groups were formed (n=15). I: Nd:YAG laser welding; II- Nd:YAG laser welding using a filling material; III- TIG welding and IV (control): no welding (intact specimens). The specimens were tested in flexural strength and the results were analyzed statistically by one-way ANOVA. There was significant differences (p<0.001) among the non-welded materials, the Co-Cr alloy being the most resistant to deflection. Comparing the welding processes, significant differences (p<0.001) where found between TIG and laser welding and also between laser alone and laser plus filling material. In conclusion, TIG welding yielded higher flexural strength means than Nd:YAG laser welding for the tested Ti, Co-Cr and Ni-Cr alloys.

Cometary dust: the diversity of primitive refractory grains

PubMed Central

Ishii, H. A.

2017-01-01

Comet dust is primitive and shows significant diversity. Our knowledge of the properties of primitive cometary particles has expanded significantly through microscale investigations of cosmic dust samples (anhydrous interplanetary dust particles (IDPs), chondritic porous (CP) IDPs and UltraCarbonaceous Antarctic micrometeorites, Stardust and Rosetta), as well as through remote sensing (Spitzer IR spectroscopy). Comet dust are aggregate particles of materials unequilibrated at submicrometre scales. We discuss the properties and processes experienced by primitive matter in comets. Primitive particles exhibit a diverse range of: structure and typology; distribution of constituents; concentration and form of carbonaceous and refractory organic matter; Mg- and Fe-contents of the silicate minerals; sulfides; existence/abundance of type II chondrule fragments; high-temperature calcium–aluminium inclusions and ameboid-olivine aggregates; and rarely occurring Mg-carbonates and magnetite, whose explanation requires aqueous alteration on parent bodies. The properties of refractory materials imply there were disc processes that resulted in different comets having particular selections of primitive materials. The diversity of primitive particles has implications for the diversity of materials in the protoplanetary disc present at the time and in the region where the comets formed. This article is part of the themed issue ‘Cometary science after Rosetta’. PMID:28554979

Charge relaxation and dynamics in organic semiconductors

NASA Astrophysics Data System (ADS)

Kwok, H. L.

2006-08-01

Charge relaxation in dispersive materials is often described in terms of the stretched exponential function (Kohlrausch law). The process can be explained using a "hopping" model which in principle, also applies to charge transport such as current conduction. This work analyzed reported transient photoconductivity data on functionalized pentacene single crystals using a geometric hopping model developed by B. Sturman et al and extracted values (or range of values) on the materials parameters relevant to charge relaxation as well as charge transport. Using the correlated disorder model (CDM), we estimated values of the carrier mobility for the pentacene samples. From these results, we observed the following: i) the transport site density appeared to be of the same order of magnitude as the carrier density; ii) it was possible to extract lower bound values on the materials parameters linked to the transport process; and iii) by matching the simulated charge decay to the transient photoconductivity data, we were able to refine estimates on the materials parameters. The data also allowed us to simulate the stretched exponential decay. Our observations suggested that the stretching index and the carrier mobility were related. Physically, such interdependence would allow one to demarcate between localized molecular interactions and distant coulomb interactions.

Fracture toughness and fractography of dental cements, lining, build-up, and filling materials.

PubMed

Mueller, H J

1990-06-01

The plane strain fracture toughness (K1c) at 23 degrees C and the fractography of zinc phosphate and zinc polycarboxylate cements, buffered glass ionomer liner, amalgam alloy admixed glass ionomer build-up material, and glass ionomer, microfilled and conventionally filled bis-GMA resin composite filling materials were analyzed by elastic-plastic short-rod and scanning electron microscopy methodologies. Results indicated that significant differences occurred in their K1c's from the lowest to the highest in the following groups of materials, (i) buffered glass ionomer, (ii) zinc phosphate, glass ionomer, zinc polycarboxylate, and alloy mixed glass ionomer, (iii) microfilled resin, and (iv) conventionally filled resin. All materials except the microfilled resin, which fractured via crack jumping, fractured via smooth crack advance. Filler debonding without any crack inhibiting process was related to materials with low K1c values. The incorporation of either buffering compounds or alloy particles into glass ionomer had no beneficial effect upon fracture toughness. This was in contrast to microfilled and conventionally filled resins where either crack blunting or crack pinning processes, respectively, were likely involved with their increased K1c's. For microfilled resin, distinct radial zones positioned around the chevron apex and characterized by plastically deformed deposited material were related to distinct crack jumps that occurred in the load versus displacement behavior. Finally, for the two remaining materials of zinc phosphate and polycarboxylate, particle cleavage and matrix debonding for the former and shear yielding for the latter occurred.

Analysis and assessment on heavy metal sources in the coastal soils developed from alluvial deposits using multivariate statistical methods.

PubMed

Li, Jinling; He, Ming; Han, Wei; Gu, Yifan

2009-05-30

An investigation on heavy metal sources, i.e., Cu, Zn, Ni, Pb, Cr, and Cd in the coastal soils of Shanghai, China, was conducted using multivariate statistical methods (principal component analysis, clustering analysis, and correlation analysis). All the results of the multivariate analysis showed that: (i) Cu, Ni, Pb, and Cd had anthropogenic sources (e.g., overuse of chemical fertilizers and pesticides, industrial and municipal discharges, animal wastes, sewage irrigation, etc.); (ii) Zn and Cr were associated with parent materials and therefore had natural sources (e.g., the weathering process of parent materials and subsequent pedo-genesis due to the alluvial deposits). The effect of heavy metals in the soils was greatly affected by soil formation, atmospheric deposition, and human activities. These findings provided essential information on the possible sources of heavy metals, which would contribute to the monitoring and assessment process of agricultural soils in worldwide regions.

Ultrasound-Induced Organogel Formation Followed by Thin Film Fabrication via Simple Doctor Blading Technique for Field-Effect Transistor Applications.

PubMed

Xu, Jiaju; Wang, Yulong; Shan, Haiquan; Lin, Yiwei; Chen, Qian; Roy, V A L; Xu, Zongxiang

2016-07-27

We demonstrate doctor blading technique to fabricate high performance transistors made up of printed small molecular materials. In this regard, we synthesize a new soluble phthalocyanine, tetra-n-butyl peripheral substituted copper(II) phthalocaynine (CuBuPc), that can easily undergo gel formation upon ultrasonic irradiation, leading to the formation of three-dimensional (3D) network composed of one-dimensional (1D) nanofibers structure. Finally, taking the advantage of thixotropic nature of the CuBuPc organogel, we use the doctor blade processing technique that limits the material wastage for the fabrication of transistor devices. Due to the ultrasound induced stronger π-π interaction, the transistor fabricated by doctor blading based on CuBuPc organogel exhibits significant increase in charge carrier mobility in comparison with other solution process techniques, thus paving a way for a simple and economically viable preparation of electronic circuits.

Two-Component Additive Manufacturing of Nanothermite by Reactive Inkjet Printing

NASA Astrophysics Data System (ADS)

Murray, Allison; Novotny, Whitney; Fleck, Trevor; Gunduz, Emre; Son, Steven; Chiu, George; Rhoads, Jeffrey

2017-06-01

To broaden the type of energetic materials that can be selectively deposited and improve the safety of their deposition, this work demonstrates the use of combinatorial inkjet printing for the selective deposition of energetic material. Two inert colloidal suspensions of nano-aluminum and nano-copper (II) oxide in dimethylformamide (DMF) with polyvinylpyrrolidone (PVP) were sequentially deposited on a substrate using piezoelectric inkjet printing. By depositing the materials at the same location, in situ mixing produced a reactive nanothermite. This process was continued to produce layers of nanothermite until the desired quantity of material was deposited. Samples with precise geometric control and high fidelity energetic performance were achieved. This work proves the feasibility of reactive inkjet printing as a means for depositing energetic materials from two largely-inert suspensions. In doing so, it opens the doors for safe material handling and the development of a wide array of energetic materials that were previously deemed incompatible with inkjet printing. This research is supported by the U.S. Department of Defense, Defense Threat Reduction Agency through Grant No. HDTRA1-15-1-0010.

Removal of Pb(II) from aqueous solutions using waste textiles/poly(acrylic acid) composite synthesized by radical polymerization technique.

PubMed

Zhou, Tao; Xia, Fafa; Deng, Yue; Zhao, Youcai

2018-05-01

Waste textiles (WTs) are the inevitable outcome of human activity and should be separated and recycled in view of sustainable development. In this work, WT was modified through grafting with acrylic acid (AA) via radical polymerization process using ceric ammonium nitrate (CAN) as an initiator and microwave and/or UV irradiation as energy supply. The acrylic acid-grafted waste textiles (WT-g-AA) thus obtained was then used as an adsorbent to remove Pb(II) from Pb(II)-containing wastewater. The effects of pH, initial concentrations of Pb(II) and adsorbent dose were investigated, and around 95% Pb(II) can be removed from the aqueous solution containing 10mg/L at pH6.0-8.0. The experimental adsorption isotherm data was fitted to the Langmuir model with maximum adsorption capacity of 35.7mg Pb/g WT-g-AA. The Pb-absorbed WT-g-AA was stripped using dilute nitric acid solution and the adsorption capacity of Pb-free material decreased from 95.4% (cycle 1) to 91.1% (cycle 3). It was considered that the WT-g-AA adsorption for Pb(II) may be realized through the ion-exchange mechanism between COOH and Pb(II). The promising results manifested that WT-g-AA powder was an efficient, eco-friendly and reusable adsorbent for the removal of Pb(II) from wastewater. Copyright © 2017. Published by Elsevier B.V.

Coating carbon nanotubes with humic acid using an eco-friendly mechanochemical method: Application for Cu(II) ions removal from water and aquatic ecotoxicity.

PubMed

Côa, Francine; Strauss, Mathias; Clemente, Zaira; Rodrigues Neto, Laís L; Lopes, Josias R; Alencar, Rafael S; Souza Filho, Antônio G; Alves, Oswaldo L; Castro, Vera Lúcia S S; Barbieri, Edison; Martinez, Diego Stéfani T

2017-12-31

In this work, industrial grade multi-walled carbon nanotubes (MWCNT) were coated with humic acid (HA) for the first time by means of a milling process, which can be considered an eco-friendly mechanochemical method to prepare materials and composites. The HA-MWCNT hybrid material was characterized by atomic force microscopy (AFM), scanning electron microscopies (SEM and STEM), X-ray photoelectron spectroscopy (XPS), termogravimetric analysis (TGA), and Raman spectroscopy. STEM and AFM images demonstrated that the MWCNTs were efficiently coated by the humic acid, thus leading to an increase of 20% in the oxygen content at the nanotube surface as observed by the XPS data. After the milling process, the carbon nanotubes were shortened as unveiled by SEM images and the values of ID/IG intensity ratio increased due to shortening of the nanotubes and increasing in the number defects at the graphitic structure of carbon nanotubes walls. The analysis of TGA data showed that the quantity of the organic matter of HA on the nanotube surface was 25%. The HA coating was responsible to favor the dispersion of MWCNTs in ultrapure water (i.e. -42mV, zeta-potential value) and to improve their capacity for copper removal. HA-MWCNTs hybrid material adsorbed 2.5 times more Cu(II) ions than oxidized MWCNTs with HNO 3 , thus evidencing that it is a very efficient adsorbent material for removing copper ions from reconstituted water. The HA-MWCNTs hybrid material did not show acute ecotoxicity to the tested aquatic model organisms (Hydra attenuata, Daphnia magna, and Danio rerio embryos) up to the highest concentration evaluated (10mgL -1 ). The results allowed concluding that the mechanochemical method is effective to coat carbon nanotubes with humic acid, thus generating a functional hybrid material with low aquatic toxicity and great potential to be applied in environmental nanotechnologies such as the removal of heavy metal ions from water. Copyright © 2017 Elsevier B.V. All rights reserved.

Layout design in order to improve efficiency in manufacturing

NASA Astrophysics Data System (ADS)

Siregar, I.; Tarigan, U.; Nasution, T. H.

2018-02-01

This research was conducted at the company that produces bobbins and ream type cigarette paper. Problems that found on the production process is the back and forth (back tracking) movement. Back and forth (back tracking) movement extending the total distance moved by the material and increase the total moment of transfer materials thus reducing the efficiency of the transfer of materials in the production process. The purpose of this study is to give design for the layout of production facilities in the company, so that the expected production produced by the company can reach the targets set by the management company. The method used in this research is the Graph-Based Construction and Travel Chart Method. The results of the analysis of the proposed layout with Graph-Based Construction was selected with a total value that is equal to the moment of transfer of 780 758 m / year. This result is better than the actual layout in the amount of 1,021,038.12 meters / year and the results of the method Travel Alternative Chart I of 826.236,60 meters/year, Alternative II of 1.004.433,56 meters / year, and Alternative III for 828,467.12 meters/year. The design layout of Graph-Based Construction material increases the transfer efficiency for 23.53%. With this layout proposal, expected production capacity will be increased along with the shortening of the distance of the displacement that must be passed by the material to be processed.

SNRB{trademark} air toxics monitoring. Final report

DOE Office of Scientific and Technical Information (OSTI.GOV)

Not Available

1994-01-01

Babcock & Wilcox (B&W) is currently conducting a project under the DOE`s Clean Coal Technology (CCT II) Program to demonstrate its SO{sub x}NO{sub x}-Rox Box{trademark} (SNRB{trademark}) process in a 5 MWe Field Demonstration Unit at Ohio Edison`s R. E. Burger Plant near Shadyside, Ohio. The objective of the SNRB{trademark} Air Toxics Monitoring Project was to provide data on SNRB{trademark} air toxics emissions control performance to B&W and to add to the DOE/EPRI/EPA data base by quantifying the flow rates of selected hazardous substances (or air toxics) in all of the major input and output streams of the SNRB{trademark} process asmore » well as the power plant. Work under the project included the collection and analysis of representative samples of all major input and output streams of the SNRB{trademark} demonstration unit and the power plant, and the subsequent laboratory analysis of these samples to determine the partitioning of the hazardous substances between the various process streams. Material balances for selected air toxics were subsequently calculated around the SNRB{trademark} and host boiler systems, including the removal efficiencies across each of the major air pollution control devices. This report presents results of the SNRB{trademark} Air Toxics Monitoring Project. In addition to the Introduction, a brief description of the test site, including the Boiler No. 8 and the SNRB{trademark} process, is included in Section H. The concentrations of air toxic emissions are presented in Section II according to compound class. Material balances are included in Section IV for three major systems: boiler, electrostatic precipitator, and SNRB{trademark}. Emission factors and removal efficiencies are also presented according to compound class in Sections V and VI, respectively. A data evaluation is provided in Section VII.« less

Enhancement of Fe diffusion in ZnSe/S laser crystals under hot isostatic pressing

NASA Astrophysics Data System (ADS)

Gafarov, Ozarfar; Martinez, Alan; Fedorov, Vladimir; Mirov, Sergey

2017-02-01

Many organic molecules have strong and narrow absorption features in the middle Infrared (mid-IR) spectral range. The ability to directly probe absorption features of molecules enables numerous mid-IR applications in non-invasive medical diagnosis, industrial processing and process control, environmental monitoring, etc. Thus, there is a strong demand for lasers operating in mid-IR spectral range. Transition metal (TM) doped II-VI semiconductors such as Fe/Cr:ZnSe/S are the material of choice for fabrication of mid-IR gain media due to favorable combination of properties: a four level energy structure, absence of excited state absorption , broad mid-IR vibronic absorption and emission bands. Despite the significant progress in post-growth thermal diffusion technology of TM:II-VI fabrication there are still some difficulties associated with diffusion of certain TM's in these materials. In this work we address the issue of poor diffusion of Fe in ZnSe/S polycrystals. It is well known that with the temperature increase the diffusion rate of impurity also increases. However, simple application of high temperatures during the diffusion process is problematic for ZnSe/S crystals due to their strong sublimation. The sublimation processes can be suppressed by application of high pressures. Hot isostatic pressing was utilized as the means for simultaneous application of high temperatures (1300°C) and high pressures (1000atm, 3000atm). It was determined that diffusion coefficient of Fe was improved 13 and 14 fold in ZnSe and ZnS, respectively, as compared to the standard diffusion at 950°C. The difference in diffusion coefficients can be due to strong increase in the grain size of polycrystals.

Mode II Interlaminar Fracture Toughness and Fatigue Characterization of a Graphite Epoxy Composite Material

NASA Technical Reports Server (NTRS)

O'Brien, T. Kevin; Johnston, William M.; Toland, Gregory J.

2010-01-01

Mode II interlaminar fracture toughness and delamination onset and growth characterization data were generated for IM7/8552 graphite epoxy composite materials from two suppliers for use in fracture mechanics analyses. Both the fracture toughness testing and the fatigue testing were conducted using the End-notched Flexure (ENF) test. The ENF test for mode II fracture toughness is currently under review by ASTM as a potential standard test method. This current draft ASTM protocol was used as a guide to conduct the tests on the IM7/8552 material. This report summarizes the test approach, methods, procedures and results of this characterization effort.

Carrier and photon dynamics in a topological insulator Bi{sub 2}Te{sub 3}/GaN type II staggered heterostructure

DOE Office of Scientific and Technical Information (OSTI.GOV)

Chaturvedi, P.; Chouksey, S.; Banerjee, D.

2015-11-09

We have demonstrated a type-II band-aligned heterostructure between pulsed laser deposited topological insulator bismuth telluride and metal organic-chemical-vapour deposited GaN on a sapphire substrate. The heterostructure shows a large valence band-offset of 3.27 eV as determined from x-ray photoelectron spectroscopy, which is close to the bandgap of GaN (3.4 eV). Further investigation using x-ray diffraction, Raman spectroscopy, and energy-dispersive x-ray spectrum reveals the stoichiometric and material properties of bismuth telluride on GaN. Steady state photon emission from GaN is found to be modulated by the charge transfer process due to diffusion across the junction. The time constant involved with the charge transfermore » process is found to be 0.6 ns by transient absorption spectroscopy. The heterostructure can be used for designing devices with different functionalities and improving the performance of the existing devices on GaN.« less

Sensor materials for an intravascular fiber optic nitric oxide sensor

NASA Astrophysics Data System (ADS)

Soller, Babs R.; Parikh, Bhairavi R.; Stahl, Russell F.

1996-04-01

Nitric oxide (NO) is an important regulatory molecule in physiological processes including neurotransmission and the control of blood pressure. It is produced in excess during septic shock, the profound hypotensive state which accompanies severe infections. In-vivo measurement of NO would enhance the understanding of its varied biological roles. Our goal is the development of an intravascular fiber-optic sensor for the continuous measurement of NO. This study evaluated nitric oxide sensitive compounds as potential sensing materials in the presence and absence of oxygen. Using absorption spectroscopy we studied both the Fe II and Fe III forms of three biologically active hemes known to rapidly react with NO: hemoglobin, myoglobin, and cytochrome-c. The Fe II forms of hemoglobin and myoglobin and the Fe III form of cytochrome-c were found to have the highest sensitivity to NO. Cytochrome c (Fe III) is selective for NO even at high oxygen levels, while myoglobin is selective only under normal oxygen levels. NO concentrations as low as 1 (mu) M can be detected with our fiber-optic spectrometer using cytochrome c, and as low as 300 nM using myoglobin. Either of these materials would be adequate to monitor the increase in nitric oxide production during the onset of septic shock.

Laboratory Studies of Cometary Materials - Continuity Between Asteroid and Comet

NASA Technical Reports Server (NTRS)

Messenger, Scott; Walker, Robert M.

2015-01-01

Laboratory analysis of cometary samples have been enabled by collection of cometary dust in the stratosphere by high altitude aircraft and by the direct sampling of the comet Wild-2 coma by the NASA Stardust spacecraft. Cometary materials are composed of a complex assemblage of highly primitive, unprocessed interstellar and primordial solar system materials as well as a variety of high temperature phases that must have condensed in the inner regions of the protoplanetary disk. These findings support and contradict conclusions of comet properties based solely on astronomical observations. These sample return missions have instead shown that there is a continuity of properties between comets and asteroids, where both types of materials show evidence for primitive and processed materials. Furthermore, these findings underscore the importance and value of direct sample return. There will be great value in comparing the findings of the Stardust cometary coma sample return mission with those of future asteroid surface sample returns OSIRIS-REx and Hayabusa II as well as future comet nucleus sample returns.

Design and characterization of a composite material based on Sr(II)-loaded clay nanotubes included within a biopolymer matrix.

PubMed

Del Buffa, Stefano; Bonini, Massimo; Ridi, Francesca; Severi, Mirko; Losi, Paola; Volpi, Silvia; Al Kayal, Tamer; Soldani, Giorgio; Baglioni, Piero

2015-06-15

This paper reports on the preparation, characterization, and cytotoxicity of a hybrid nanocomposite material made of Sr(II)-loaded Halloysite nanotubes included within a biopolymer (3-polyhydroxybutyrate-co-3-hydroxyvalerate) matrix. The Sr(II)-loaded inorganic scaffold is intended to provide mechanical resistance, multi-scale porosity, and to favor the in-situ regeneration of bone tissue thanks to its biocompatibility and bioactivity. The interaction of the hybrid system with the physiological environment is mediated by the biopolymer coating, which acts as a binder, as well as a diffusional barrier to the Sr(II) release. The degradation of the polymer progressively leads to the exposure of the Sr(II)-loaded Halloysite scaffold, tuning its interaction with osteogenic cells. The in vitro biocompatibility of the composite was demonstrated by cytotoxicity tests on L929 fibroblast cells. The results indicate that this composite material could be of interest for multiple strategies in the field of bone tissue engineering. Copyright © 2015 Elsevier Inc. All rights reserved.

Radical formation, chemical processing, and explosion of interstellar grains

NASA Technical Reports Server (NTRS)

Greenberg, J. M.

1976-01-01

The ultraviolet radiation in interstellar space is shown to create a sufficient steady-state density of free radicals in the grain mantle material consisting of oxygen, carbon, nitrogen, and hydrogen to satisfy the critical condition for initiation of chain reactions. The criterion for minimum critical particle size for maintaining the chain reaction is of the order of the larger grain sizes in a distribution satisfying the average extinction and polarization measures. The triggering of the explosion of interstellar grains leading to the ejection of complex interstellar molecules is shown to be most probable where the grains are largest and where radiation is suddenly introduced; i.e., in regions of new star formation. Similar conditions prevail at the boundaries between very dark clouds and H II regions. When the energy released by the chemical activity of the free radicals is inadequate to explode the grain, the resulting mantle material must consist of extremely large organic molecules which are much more resistant to the hostile environment of H II regions than the classical dirty-ice mantles made up of water, methane, and ammonia.

Carbon/tin oxide composite electrodes for improved lithium-ion batteries

DOE PAGES

Li, Yunchao; Levine, Alan M.; Zhang, Jinshui; ...

2018-05-17

Tin and tin oxide-based electrodes are promising high-capacity anodes for lithium-ion batteries. However, poor capacity retention is the major issue with these materials due to the large volumetric expansion that occurs when lithium is alloyed with tin during lithiation and delithiation process. Here, a method to prepare a low-cost, scalable carbon and tin(II) oxide composite anode is reported. The composite material was prepared by ball milling of carbon recovered from used tire powders with 25 wt% tin(II) oxide to form lithium-ion battery anode. With the impact of energy from the ball milling, tin oxide powders were uniformly distributed inside themore » pores of waste-tire-derived carbon. During lithiation and delithiation, the carbon matrix can effectively absorb the volume expansion caused by tin, thereby minimizing pulverization and capacity fade of the electrodes. In conclusion, the as-synthesized anode yielded a capacity of 690 mAh g –1 after 300 cycles at a current density of 40 mA g –1 with a stable battery performance.« less

Carbon/tin oxide composite electrodes for improved lithium-ion batteries

DOE Office of Scientific and Technical Information (OSTI.GOV)

Li, Yunchao; Levine, Alan M.; Zhang, Jinshui

Tin and tin oxide-based electrodes are promising high-capacity anodes for lithium-ion batteries. However, poor capacity retention is the major issue with these materials due to the large volumetric expansion that occurs when lithium is alloyed with tin during lithiation and delithiation process. Here, a method to prepare a low-cost, scalable carbon and tin(II) oxide composite anode is reported. The composite material was prepared by ball milling of carbon recovered from used tire powders with 25 wt% tin(II) oxide to form lithium-ion battery anode. With the impact of energy from the ball milling, tin oxide powders were uniformly distributed inside themore » pores of waste-tire-derived carbon. During lithiation and delithiation, the carbon matrix can effectively absorb the volume expansion caused by tin, thereby minimizing pulverization and capacity fade of the electrodes. In conclusion, the as-synthesized anode yielded a capacity of 690 mAh g –1 after 300 cycles at a current density of 40 mA g –1 with a stable battery performance.« less

Colloidal Material Box: In-situ Observations of Colloidal Self-Assembly and Liquid Crystal Phase Transitions in Microgravity

NASA Astrophysics Data System (ADS)

Li, WeiBin; Lan, Ding; Sun, ZhiBin; Geng, BaoMing; Wang, XiaoQing; Tian, WeiQian; Zhai, GuangJie; Wang, YuRen

2016-05-01

To study the self-assembly behavior of colloidal spheres in the solid/liquid interface and elucidate the mechanism of liquid crystal phase transition under microgravity, a Colloidal Material Box (CMB) was designed which consists of three modules: (i) colloidal evaporation experimental module, made up of a sample management unit, an injection management unit and an optical observation unit; (ii) liquid crystal phase transition experimental module, including a sample management unit and an optical observation unit; (iii) electronic control module. The following two experimental plans will be performed inside the CMB aboard the SJ-10 satellite in space. (i) Self-assembly of colloidal spheres (with and without Au shell) induced by droplet evaporation, allowing observation of the dynamic process of the colloidal spheres within the droplet and the change of the droplet outer profile during evaporation; (ii) Phase behavior of Mg2Al LDHs suspensions in microgravity. The experimental results will be the first experimental observations of depositing ordered colloidal crystals and their self-assembly behavior under microgravity, and will illustrate the influence of gravity on liquid crystal phase transition.

Environmentally Safe and Effective Processes for Paint Removal

DTIC Science & Technology

1995-04-01

Urea Formaldehyde 3.5 1.5 Type III Melamine Formaldehyde 4.0 1.5 Type IV Phenol Formaldehyde 3.5 1.5...Polyester 3.0 34 - 42 1.04 - 1.46 Type II Urea Formaldehyde 3.5 54 - 62 1.47- 1.54 Type III Melamine Formaldehyde 4.0 64- 72 1.47- 1.52 Type IV Phenol... Melamine Formaldehyde electronics industry and to remove coatings from fibreglass and composite materials. Melamine formaldehyde resin is produced

Direct Reduction Processes for the Production of Titanium Metal. Report of the Ad Hoc Panel of the Committee on Technical Aspects of Critical and Strategic Materials

DTIC Science & Technology

1974-03-01

Members Dr. Nevin K. Hiester Director, Technoeconomics Program Stanford Research Institute Menlo Park, California 94025 Dr. Michael Hoch...Titanium Sponge Statistics 11 TABLE II. Plants for the Production of Titanium Sponge 12 TABLE III. Estimated Sponge Production...de Nemours and Co. built the first nongovernment pilot plant . That year is considered the start of small-scale commercial pro- duction of

Control of GaAs Microwave Schottky Diode Electrical Characteristics by Contact Geometry: The Gap Diode.

DTIC Science & Technology

1982-05-01

semiconductor Schottky-barrier contacts are used in many semiconductor devices, including switches, rectifiers, varactors , IMPATTs, mixer and detector...ionic materials such as most of the II-VI compound semiconductors (e.g. ZnS and ZnO) and the transition-metal oxides , the barrier height is strongly...the alloying process described above is nonuniformity, due to the incomplete removal of residual surface oxides prior to the evaporation of the metal

Bio-organic compounds and glassy microparticles in lunar fines and other materials.

PubMed

Fox, S W; Harada, K; Hare, P E; Hinsch, G; Mueller, G

1970-01-30

Acid hydrolyzates of aqueous extracts indicated: glycine, alanine, glutamic acid, serine, aspartic acid, threonine, and I-diaminopropionic acid. The sources of these amino acids may be terrestrial contaminants, fuel exhaust products, or indigenous lunar material. The lunar particles found in the sample include: (i) spherules, rotational ellipsoids, dumbbells, tear-drops, rings, and crescents which have (ii) diameters of 0.1 to 500 microns; (iii) budlike features on the particles; and (iv) chemical inhomogeneity (electron probe). Some of the processes and results inferred for the moon have been simulated by the electron beam and low pressure of the electron microscope. Basalt (Kilauea-lki) and chondrite (Orgueil) have been found to behave similarly.

Clathrate compounds and method of manufacturing

DOEpatents

Nolas, George S [Tampa, FL; Witanachchi, Sarath [Tampa, FL; Mukherjee, Pritish [Tampa, FL

2009-05-19

The present invention comprises new materials, material structures, and processes of fabrication of such that may be used in technologies involving the conversion of light to electricity and/or heat to electricity, and in optoelectronics technologies. The present invention provide for the fabrication of a clathrate compound comprising a type II clathrate lattice with atoms of silicon and germanium as a main framework forming lattice spacings within the framework, wherein the clathrate lattice follows the general formula Si.sub.136-yGe.sub.y, where y indicates the number of Ge atoms present in the main framework and 136-y indicates the number of Si atoms present in the main framework, and wherein y>0.

Origami-inspired active graphene-based paper for programmable instant self-folding walking devices.

PubMed

Mu, Jiuke; Hou, Chengyi; Wang, Hongzhi; Li, Yaogang; Zhang, Qinghong; Zhu, Meifang

2015-11-01

Origami-inspired active graphene-based paper with programmed gradients in vertical and lateral directions is developed to address many of the limitations of polymer active materials including slow response and violent operation methods. Specifically, we used function-designed graphene oxide as nanoscale building blocks to fabricate an all-graphene self-folding paper that has a single-component gradient structure. A functional device composed of this graphene paper can (i) adopt predesigned shapes, (ii) walk, and (iii) turn a corner. These processes can be remote-controlled by gentle light or heating. We believe that this self-folding material holds potential for a wide range of applications such as sensing, artificial muscles, and robotics.

Shear History Extensional Rheology Experiment II (SHERE II) Microgravity Rheology with Non-Newtonian Polymeric Fluids

NASA Technical Reports Server (NTRS)

Jaishankar, Aditya; Haward, Simon; Hall, Nancy Rabel; Magee, Kevin; McKinley, Gareth

2012-01-01

The primary objective of SHERE II is to study the effect of torsional preshear on the subsequent extensional behavior of filled viscoelastic suspensions. Microgravity environment eliminates gravitational sagging that makes Earth-based experiments of extensional rheology challenging. Experiments may serve as an idealized model system to study the properties of lunar regolith-polymeric binder based construction materials. Filled polymeric suspensions are ubiquitous in foods, cosmetics, detergents, biomedical materials, etc.

A new ejecta shell surrounding a Wolf-Rayet star in the LMC

NASA Technical Reports Server (NTRS)

Garnett, Donald R.; Chu, You-Hua

1994-01-01

We have obtained CCD spectra of newly discovered shell-like nebulae around the WN4 star Breysacher 13 and the WN1 star Breysacher 2 in the Large Magellanic Cloud (LMC). The shell around Br 13 shows definite signs of enrichment in both nitrogen and helium, having much stronger (N II) and He I emission lines than are seen in typical LMC H II regions. From the measured electron temperature of about 17,000 K in the shell, we derive He/H and N/O abundance ratios which are factors of 2 and more than 10 higher, respectively, than the average LMC interstellar values. The derived oxygen abundance in the Br 13 shell is down by a factor of 8 compared to the local LMC interstellar medium (ISM); however, the derived electron temperature is affected by the presence of an incomplete shock arising from the interaction of the stellar wind with photoionized material. This uncertainty does not affect the basic conclusion that the Br 13 shell is enriched by processed material from the Wolf-Rayet star. In contrast, the shell around Br 2 shows no clear evidence of enrichment. The nebular spectrum is characterized by extremely strong (O III) and He II emission and very weak (N II). We derive normal He, O, and N abundances from our spectrum. This object therefore appears to be simply a wind-blown structure associated with a relatively dense cloud near the Wolf-Rayet star, although the very high-ionization state of the gas is unusual for a nebula associated with a Wolf-Rayet star.

Influence of surrounding environment on subcritical crack growth in marble

NASA Astrophysics Data System (ADS)

Nara, Yoshitaka; Kashiwaya, Koki; Nishida, Yuki; , Toshinori, Ii

2017-06-01

Understanding subcritical crack growth in rock is essential for determining appropriate measures to ensure the long-term integrity of rock masses surrounding structures and for construction from rock material. In this study, subcritical crack growth in marble was investigated experimentally, focusing on the influence of the surrounding environment on the relationship between the crack velocity and stress intensity factor. The crack velocity increased with increasing temperature and/or relative humidity. In all cases, the crack velocity increased with increasing stress intensity factor. However, for Carrara marble (CM) in air, we observed a region in which the crack velocity still increased with temperature, but the increase in the crack velocity with increasing stress intensity factor was not significant. This is similar to Region II of subcritical crack growth observed in glass in air. Region II in glass is controlled by mass transport to the crack tip. In the case of rock, the transport of water to the crack tip is important. In general, Region II is not observed for subcritical crack growth in rock materials, because rocks contain water. Because the porosity of CM is very low, the amount of water contained in the marble is also very small. Therefore, our results imply that we observed Region II in CM. Because the crack velocity increased in both water and air with increasing temperature and humidity, we concluded that dry conditions at low temperature are desirable for the long-term integrity of a carbonate rock mass. Additionally, mass transport to the crack tip is an important process for subcritical crack growth in rock with low porosity.

Drying time of tray adhesive for adequate tensile bond strength between polyvinylsiloxane impression and tray resin material.

PubMed

Yi, Myong-Hee; Shim, Joon-Sung; Lee, Keun-Woo; Chung, Moon-Kyu

2009-07-01

Use of custom tray and tray adhesive is clinically recommended for elastomeric impression material. However there is not clear mention of drying time of tray adhesive in achieving appropriate bonding strength of tray material and impression material. This study is to investigate an appropriate drying time of tray adhesives by evaluating tensile bonding strength between two types of polyvinylsiloxane impression materials and resin tray, according to various drying time intervals of tray adhesives, and with different manufacturing company combination of impression material and tray adhesive. Adhesives used in this study were Silfix (Dentsply Caulk, Milford, Del, USA) and VPS Tray Adhesive (3M ESPE, Seefeld, Germany) and impression materials were Aquasil Ultra (monophase regular set, Dentsply Caulk, Milford, Del, USA) and Imprint II Garant (regular body, 3M ESPE, Seefeld, Germany). They were used combinations from the same manufacture and exchanged combinations of the two. The drying time was designed to air dry, 5 minutes, 10 minutes, 15 minutes, 20 minutes, and 25 minutes. Total 240 of test specimens were prepared by auto-polymerizing tray material (Instant Tray Mix, Lang, Wheeling, Il, USA) with 10 specimens in each group. The specimens were placed in the Universal Testing machine (Instron, model 3366, Instron Corp, University avenue, Nowood, MA, USA) to perform the tensile test (cross head speed 5 mm/min). The statistically efficient drying time was evaluated through ANOVA and Scheffe test. All the tests were performed at 95% confidence level. The results revealed that at least 10 minutes is needed for Silfix-Aquasil, and 15 minutes for VPS Tray Adhesive-Imprint II, to attain an appropriate tensile bonding strength. VPS Tray Adhesive-Imprint II had a superior tensile bonding strength when compared to Silfix-Aquasil over 15 minutes. Silfix-Aquasil had a superior bonding strength to VPS Tray Adhesive-Aquasil, and VPS Tray Adhesive-Imprint II had a superior tensile bonding strength to Silfix-Imprint II at all drying periods. Significant increase in tensile bonding strength with Silfix-Aquasil and VPS Tray adhesive-Imprint II combination until 10 and 15 minutes respectively. Tray adhesive-impression material combination from the same company presented higher tensile bonding strength at all drying time intervals than when using tray adhesive-impression material of different manufactures.

Adsorption of Pb(II), Cu(II), Cd(II), Zn(II), Ni(II), Fe(II), and As(V) on bacterially produced metal sulfides.

PubMed

Jong, Tony; Parry, David L

2004-07-01

The adsorption of Pb(II), Cu(II), Cd(II), Zn(II), Ni(II), Fe(II) and As(V) onto bacterially produced metal sulfide (BPMS) material was investigated using a batch equilibrium method. It was found that the sulfide material had adsorptive properties comparable with those of other adsorbents with respect to the specific uptake of a range of metals and, the levels to which dissolved metal concentrations in solution can be reduced. The percentage of adsorption increased with increasing pH and adsorbent dose, but decreased with increasing initial dissolved metal concentration. The pH of the solution was the most important parameter controlling adsorption of Cd(II), Cu(II), Fe(II), Ni(II), Pb(II), Zn(II), and As(V) by BPMS. The adsorption data were successfully modeled using the Langmuir adsorption isotherm. Desorption experiments showed that the reversibility of adsorption was low, suggesting high-affinity adsorption governed by chemisorption. The mechanism of adsorption for the divalent metals was thought to be the formation of strong, inner-sphere complexes involving surface hydroxyl groups. However, the mechanism for the adsorption of As(V) by BPMS appears to be distinct from that of surface hydroxyl exchange. These results have important implications to the management of metal sulfide sludge produced by bacterial sulfate reduction.

Preparation, characterization and dissolution of passive oxide film on the 400 series stainless steel surfaces

NASA Astrophysics Data System (ADS)

Sathyaseelan, V. S.; Rufus, A. L.; Chandramohan, P.; Subramanian, H.; Velmurugan, S.

2015-12-01

Full system decontamination of Primary Heat Transport (PHT) system of Pressurised Heavy Water Reactors (PHWRs) resulted in low decontamination factors (DF) on stainless steel (SS) surfaces. Hence, studies were carried out with 403 SS and 410 SS that are the material of construction of "End-Fitting body" and "End-Fitting Liner tubes". Three formulations were evaluated for the dissolution of passive films formed over these alloys viz., i) Two-step process consisting of oxidation and reduction reactions, ii) Dilute Chemical Decontamination (DCD) and iii) High Temperature Process. The two-step and high temperature processes could dissolve the oxide completely while the DCD process could remove only 60%. Various techniques like XRD, Raman spectroscopy and SEM-EDX were used for assessing the dissolution process. The two-step process is time consuming, laborious while the high temperature process is less time consuming and is recommended for SS decontamination.

Advanced Booster Composite Case/Polybenzimidazole Nitrile Butadiene Rubber Insulation Development

NASA Technical Reports Server (NTRS)

Gentz, Steve; Taylor, Robert; Nettles, Mindy

2015-01-01

The NASA Engineering and Safety Center (NESC) was requested to examine processing sensitivities (e.g., cure temperature control/variance, debonds, density variations) of polybenzimidazole nitrile butadiene rubber (PBI-NBR) insulation, case fiber, and resin systems and to evaluate nondestructive evaluation (NDE) and damage tolerance methods/models required to support human-rated composite motor cases. The proposed use of composite motor cases in Blocks IA and II was expected to increase performance capability through optimizing operating pressure and increasing propellant mass fraction. This assessment was to support the evaluation of risk reduction for large booster component development/fabrication, NDE of low mass-to-strength ratio material structures, and solid booster propellant formulation as requested in the Space Launch System NASA Research Announcement for Advanced Booster Engineering Demonstration and/or Risk Reduction. Composite case materials and high-energy propellants represent an enabling capability in the Agency's ability to provide affordable, high-performing advanced booster concepts. The NESC team was requested to provide an assessment of co- and multiple-cure processing of composite case and PBI-NBR insulation materials and evaluation of high-energy propellant formulations.

Cadmium-free junction fabrication process for CuInSe.sub.2 thin film solar cells

DOEpatents

Ramanathan, Kannan V.; Contreras, Miguel A.; Bhattacharya, Raghu N.; Keane, James; Noufi, Rommel

1999-01-01

The present invention provides an economical, simple, dry and controllable semiconductor layer junction forming process to make cadmium free high efficiency photovoltaic cells having a first layer comprised primarily of copper indium diselenide having a thin doped copper indium diselenide n-type region, generated by thermal diffusion with a group II(b) element such as zinc, and a halide, such as chlorine, and a second layer comprised of a conventional zinc oxide bilayer. A photovoltaic device according the present invention includes a first thin film layer of semiconductor material formed primarily from copper indium diselenide. Doping of the copper indium diselenide with zinc chloride is accomplished using either a zinc chloride solution or a solid zinc chloride material. Thermal diffusion of zinc chloride into the copper indium diselenide upper region creates the thin n-type copper indium diselenide surface. A second thin film layer of semiconductor material comprising zinc oxide is then applied in two layers. The first layer comprises a thin layer of high resistivity zinc oxide. The second relatively thick layer of zinc oxide is doped to exhibit low resistivity.

49 CFR 172.407 - Label specifications.

Code of Federal Regulations, 2012 CFR

2012-10-01

... one color background of green, red or blue. (ii) White must be used for the text and class number for... Hazardous Materials Safety, Office of Hazardous Materials Standards, Room 8422, Nassif Building, 400 Seventh... markings and hazard warning labels and placards: (i) For Red—Use PANTONE ® 186 U (ii) For Orange—Use...

Validation and refinement of mixture volumetric material properties identified in superpave monitoring project II : phase II : [summary].

DOT National Transportation Integrated Search

2015-02-01

Superpave is a set of methods and materials for asphalt paving and the primary method : used by the Florida Department of Transportation. It is well documented that performance : of asphalt mixtures is strongly affected by size composition of aggrega...

77 FR 5846 - Importer of Controlled Substances; Notice of Registration

Federal Register 2010, 2011, 2012, 2013, 2014

2012-02-06

... import narcotic raw material are not appropriate, in accordance with 72 FR 3417 (2007). DEA has... basic classes of controlled substances: Drug Schedule Phenylacetone (8501) II Opium, raw (9600) II Poppy... to use it as a base material in the bulk manufacture of another controlled substance. No comments or...

40 CFR 52.515 - Original identification of plan section.

Code of Federal Regulations, 2012 CFR

2012-07-01

..., 567 F. 2d 1091 (D.C. Cir. 1977)), Congressional action, or rescission by EPA. (20) Inspection and... September 30, 1993. (ii) Additional material. (A) Remainder of October 22, 1993 District of Columbia..., Freeboard ratio, Mayor, Vehicular fuel tank. Abbreviations: (Degree), VOC, “%”. (ii) Additional material. (A...

Morphological transformation of soot: investigation of microphysical processes during the condensation of sulphuric acid and limonene ozonolysis products vapours

NASA Astrophysics Data System (ADS)

Pathak, R. K. P.; Pei, X.; Hallquist, M.; Pagels, J. H.

2017-12-01

Morphological transformation of soot particle by condensation of low volatility materials on it is a dominant atmospheric process with serious implications for its optical and hygroscopic properties, and atmospheric lifetime. In this study, the morphological transformation of soot agglomerate under the influence of condensation of vapours of sulphuric acid, and/or limonene ozonolysis products were investigated systematically using a Differential Mobility Analyser-Aerosol Particle Mass Analyser (DMA-APM) and the Tandem DMA techniques integrated with a laminar flow-tube system. We discovered that the morphology transformation of soot in general was a sequence of two-step process, i.e. (i) filling of void space within soot agglomerate; (ii) growth of particle diameter. These two steps followed and complimented each other. In the very beginning the filling was the dominant process followed by growth until it led to the accumulation of enough material that in turn exerted surface forces that eventually facilitated the further filling. The filling of void space was constrained by the initial morphology of fresh soot and the nature and amount of the material condensed. This process continued in several sequential steps until all void space within the soot agglomerate was filled completely and then growth of a spherical particle continued as long as mass was condensed on it. In this study, we developed a framework to quantify the microphysical transformation of soot upon the condensation of various materials. The framework utilized experimental data and hypothesis of ideal sphere growth and filling of voids to quantify the distribution of condensed materials in these two processes complimenting each other. Using this framework, we have quantified the percentage of material that went into processes of particle growth and void filling at each step. Using the same framework, we further estimated the fraction of internal voids and open voids and used this information to derive the volume equivalent diameter of soot agglomerate containing internal voids and calculated in-situ dynamic shape factor. Our study is the first study that tracks in situ microphysical changes in soot morphology quantitatively, providing the detailed status of both fresh and coated soot particles.

Experimental characterization of meteoric material exposed to a high enthalpy flow in the Plasmatron

NASA Astrophysics Data System (ADS)

Zavalan, Luiza; Bariselli, Federico; Barros Dias, Bruno; Helber, Bernd; Magin, Thierry

2017-04-01

Meteoroids, disintegrated during their entry in the atmosphere, contribute massively to the input of cosmic metals to Earth. Yet, this phenomenon is not well understood. Experimental studies on meteor material degradation in high enthalpy facilities are scarce and often do not provide quantitative data which are necessary for the validation of the simulation tools. In this work, we tried to duplicate typical meteor flight conditions in a ground testing facility to analyze the thermo-chemical degradation mechanisms by reproducing the stagnation point region conditions. The VKI Plasmatron is one of the most powerful induction-coupled plasma wind-tunnels in the world. It represents an important tool for the characterization of ceramic and ablative materials employed in the fabrication of Thermal Protection Systems (TPS) of spacecraft. The testing methodology and measurement techniques used for TPS characterization were adapted for the investigation of evaporation and melting in samples of basalt (meteorite surrogate) and ordinary chondrite. The materials were exposed to stagnation point heat fluxes of 1 MW/m2 and 3 MW/m2. During the test, numerous local pockets were formed at the surface of the samples by the emergence of gas bubbles. Images recorded through a digital 14bit CCD camera system clearly revealed the frothing of the surface for both tested materials. This process appeared to be more heterogeneous for the basaltic samples than for the ordinary chondritic material. Surface temperature measurements obtained via a two-color pyrometer showed a maximum surface temperature in the range between 2160 and 2490 Kelvins. Some of the basaltic samples fractured during the tests. This is probably due to the strong thermal gradients experienced by the material in these harsh conditions. Therefore, the surface temperature measurements suffered sudden drops in correspondence with the fracturing time. Emission spectra of air and ablated species were collected with resolution in time and space thanks to a set-up counting three synchronized spectrometers with different line of sights. The spectra indicated dominant radiating molecules in the range from 240 to 450 nm [CN Violet and N2+ (1-)]. By analyzing the spectra of all tests, it was observed that the most volatile components Na and K were released more efficiently than the Si, Fe, Ca, Mg and Ti components. Also, some ionized atoms (Ca II, Mg II and Fe II) were identified, the lines of Ca II being the strongest in the range from 350 to 450 nm. The differences in composition between the two materials was highlighted by tracking the emission histories of the neutral elements. For example, the emission of the Si line (288.2 nm) was almost null for the ordinary chondrite compared to the basalt. Moreover, iron lines, which were present in the spectra collected for the ordinary chondrite, were not visible for basalt. These results are consistent with the different chemical composition of both materials.

The hierarchical porous structure bio-char assessments produced by co-pyrolysis of municipal sewage sludge and hazelnut shell and Cu(II) adsorption kinetics.

PubMed

Zhao, Bing; Xu, Xinyang; Zeng, Fanqiang; Li, Haibo; Chen, Xi

2018-05-04

The co-pyrolysis technology was applied to municipal sewage sludge (MSS) and hazelnut shell with alkaline activating agent K 2 CO 3 under N 2 atmosphere. The innovative bio-char produced by co-pyrolysis had significant physical and chemical characteristics. The specific surface area reached 1990.23 m 2 /g, and the iodine absorption number was 1068.22 mg/g after co-pyrolysis at 850 °C. Although hazelnut shell was a kind of solid waste, it also had abundant cellulose resource, which could contribute to porous structure of bio-char during co-pyrolysis with MSS and decrease total heavy metals contents of raw material to increase security of bio-chars. Meanwhile, the residual fractions of heavy metals in bio-char were above 92.95% after co-pyrolysis at 900 °C except Cd to prevent heavy metals digestion, and the bio-char presented significant immobilization behavior from co-pyrolysis technology. Moreover, the yield and the iodine absorption number of bio-chars under different process variables were analyzed, and it was confirmed that appropriate process variables could contribute the yield and the iodine absorption number of bio-char and prevent to etch pore structure excessively to collapse. The changes of surface functional groups and crystallographic structure before and after co-pyrolysis were analyzed by FTIR and XRD, respectively. The hierarchical porous structure of bio-char was presented by SEM and N 2 adsorption-desorption isotherm. The Cu(II) adsorption capacity of the bio-char was 42.28 mg/g after 24 h, and surface functional groups acted as active binding sites for Cu(II) adsorption. Langmuir model and pseudo-second-order model can describe process of Cu(II) adsorption well.

Methods and systems for utilizing carbide lime or slag

DOE Office of Scientific and Technical Information (OSTI.GOV)

Devenney, Martin; Fernandez, Miguel; Chen, Irvin

Provided herein are methods comprising a) treating a slag solid or carbide lime suspension with an ammonium salt in water to produce an aqueous solution comprising calcium salt, ammonium salt, and solids; b) contacting the aqueous solution with carbon dioxide from an industrial process under one or more precipitation conditions to produce a precipitation material comprising calcium carbonate and a supernatant aqueous solution wherein the precipitation material and the supernatant aqueous solution comprise residual ammonium salt; and c) removing and optionally recovering ammonia and/or ammonium salt using one or more steps of (i) recovering a gas exhaust stream comprising ammoniamore » during the treating and/or the contacting step; (ii) recovering the residual ammonium salt from the supernatant aqueous solution; and (iii) removing and optionally recovering the residual ammonium salt from the precipitation material.« less

Preliminary Results from Duplex Procedure for Obtain of Fe Based Materials for Automotive Applications

NASA Astrophysics Data System (ADS)

Crăciun, R. C.; Stanciu, S.; Geantă, V.; Voiculescu, I.; Manole, V.; Gârneţ, I. A.; Alexandru, A.; Cimpoesu, N.; Săndulache, F.

2017-06-01

Abstract Iron based materials still represent a high percentage from metallic materials used in industry, in general, and in automotive industry, in particular. In this case we used a duplex process in order to obtain the FeMnSiAl experimental alloy for a more efficient use of various units. In the first stage iron, manganese, silicon and aluminum were melted and mixed together using arc melting technology and for the second stage the alloy was re-melt for homogeneity in an induction furnace. Chemical composition, after each melting step, was analyzed using EDS Bruker detector for various areas and microstructural characterization using SEM, VegaTescan LMH II with SE detector, equipment. This alloy is proposed as a metallic approach of mechanical dumpers used in automotive industry for low and medium impact contacts.

Microbial ecology to manage processes in environmental biotechnology.

PubMed

Rittmann, Bruce E

2006-06-01

Microbial ecology and environmental biotechnology are inherently tied to each other. The concepts and tools of microbial ecology are the basis for managing processes in environmental biotechnology; and these processes provide interesting ecosystems to advance the concepts and tools of microbial ecology. Revolutionary advancements in molecular tools to understand the structure and function of microbial communities are bolstering the power of microbial ecology. A push from advances in modern materials along with a pull from a societal need to become more sustainable is enabling environmental biotechnology to create novel processes. How do these two fields work together? Five principles illuminate the way: (i) aim for big benefits; (ii) develop and apply more powerful tools to understand microbial communities; (iii) follow the electrons; (iv) retain slow-growing biomass; and (v) integrate, integrate, integrate.

Potential for microbial oxidation of ferrous iron in basaltic glass.

PubMed

Xiong, Mai Yia; Shelobolina, Evgenya S; Roden, Eric E

2015-05-01

Basaltic glass (BG) is an amorphous ferrous iron [Fe(II)]-containing material present in basaltic rocks, which are abundant on rocky planets such as Earth and Mars. Previous research has suggested that Fe(II) in BG can serve as an energy source for chemolithotrophic microbial metabolism, which has important ramifications for potential past and present microbial life on Mars. However, to date there has been no direct demonstration of microbially catalyzed oxidation of Fe(II) in BG. In this study, three different culture systems were used to investigate the potential for microbial oxidation of Fe(II) in BG, including (1) the chemolithoautotrophic Fe(II)-oxidizing, nitrate-reducing "Straub culture"; (2) the mixotrophic Fe(II)-oxidizing, nitrate-reducing organism Desulfitobacterium frappieri strain G2; and (3) indigenous microorganisms from a streambed Fe seep in Wisconsin. The BG employed consisted of clay and silt-sized particles of freshly quenched lava from the TEB flow in Kilauea, Hawaii. Soluble Fe(II) or chemically reduced NAu-2 smectite (RS) were employed as positive controls to verify Fe(II) oxidation activity in the culture systems. All three systems demonstrated oxidation of soluble Fe(II) and/or structural Fe(II) in RS, whereas no oxidation of Fe(II) in BG material was observed. The inability of the Straub culture to oxidize Fe(II) in BG was particularly surprising, as this culture can oxidize other insoluble Fe(II)-bearing minerals such as biotite, magnetite, and siderite. Although the reason for the resistance of the BG toward enzymatic oxidation remains unknown, it seems possible that the absence of distinct crystal faces or edge sites in the amorphous glass renders the material resistant to such attack. These findings have implications with regard to the idea that Fe(II)-Si-rich phases in basalt rocks could provide a basis for chemolithotrophic microbial life on Mars, specifically in neutral-pH environments where acid-promoted mineral dissolution and utilization of dissolved Fe(II) as an energy source is not likely to take place.

Author Contribution to the Pu Handbook II: Chapter 37 LLNL Integrated Sample Preparation Glovebox (TEM) Section

DOE Office of Scientific and Technical Information (OSTI.GOV)

Wall, Mark A.

The development of our Integrated Actinide Sample Preparation Laboratory (IASPL) commenced in 1998 driven by the need to perform transmission electron microscopy studies on naturally aged plutonium and its alloys looking for the microstructural effects of the radiological decay process (1). Remodeling and construction of a laboratory within the Chemistry and Materials Science Directorate facilities at LLNL was required to turn a standard radiological laboratory into a Radiological Materials Area (RMA) and Radiological Buffer Area (RBA) containing type I, II and III workplaces. Two inert atmosphere dry-train glove boxes with antechambers and entry/exit fumehoods (Figure 1), having a baseline atmospheremore » of 1 ppm oxygen and 1 ppm water vapor, a utility fumehood and a portable, and a third double-walled enclosure have been installed and commissioned. These capabilities, along with highly trained technical staff, facilitate the safe operation of sample preparation processes and instrumentation, and sample handling while minimizing oxidation or corrosion of the plutonium. In addition, we are currently developing the capability to safely transfer small metallographically prepared samples to a mini-SEM for microstructural imaging and chemical analysis. The gloveboxes continue to be the most crucial element of the laboratory allowing nearly oxide-free sample preparation for a wide variety of LLNL-based characterization experiments, which includes transmission electron microscopy, electron energy loss spectroscopy, optical microscopy, electrical resistivity, ion implantation, X-ray diffraction and absorption, magnetometry, metrological surface measurements, high-pressure diamond anvil cell equation-of-state, phonon dispersion measurements, X-ray absorption and emission spectroscopy, and differential scanning calorimetry. The sample preparation and materials processing capabilities in the IASPL have also facilitated experimentation at world-class facilities such as the Advanced Photon Source at Argonne National Laboratory, the European Synchrotron Radiation Facility in Grenoble, France, the Stanford Synchrotron Radiation Facility, the National Synchrotron Light Source at Brookhaven National Laboratory, the Advanced Light Source at Lawrence Berkeley National Laboratory, and the Triumph Accelerator in Canada.« less

DOE Office of Scientific and Technical Information (OSTI.GOV)

Sublet, J.-Ch., E-mail: jean-christophe.sublet@ukaea.uk; Eastwood, J.W.; Morgan, J.G.

Fispact-II is a code system and library database for modelling activation-transmutation processes, depletion-burn-up, time dependent inventory and radiation damage source terms caused by nuclear reactions and decays. The Fispact-II code, written in object-style Fortran, follows the evolution of material irradiated by neutrons, alphas, gammas, protons, or deuterons, and provides a wide range of derived radiological output quantities to satisfy most needs for nuclear applications. It can be used with any ENDF-compliant group library data for nuclear reactions, particle-induced and spontaneous fission yields, and radioactive decay (including but not limited to TENDL-2015, ENDF/B-VII.1, JEFF-3.2, JENDL-4.0u, CENDL-3.1 processed into fine-group-structure files, GEFY-5.2more » and UKDD-16), as well as resolved and unresolved resonance range probability tables for self-shielding corrections and updated radiological hazard indices. The code has many novel features including: extension of the energy range up to 1 GeV; additional neutron physics including self-shielding effects, temperature dependence, thin and thick target yields; pathway analysis; and sensitivity and uncertainty quantification and propagation using full covariance data. The latest ENDF libraries such as TENDL encompass thousands of target isotopes. Nuclear data libraries for Fispact-II are prepared from these using processing codes PREPRO, NJOY and CALENDF. These data include resonance parameters, cross sections with covariances, probability tables in the resonance ranges, PKA spectra, kerma, dpa, gas and radionuclide production and energy-dependent fission yields, supplemented with all 27 decay types. All such data for the five most important incident particles are provided in evaluated data tables. The Fispact-II simulation software is described in detail in this paper, together with the nuclear data libraries. The Fispact-II system also includes several utility programs for code-use optimisation, visualisation and production of secondary radiological quantities. Included in the paper are summaries of results from the suite of verification and validation reports available with the code.« less

Macrocyclic receptors immobilized to monodisperse porous polymer particles by chemical grafting and physical impregnation for strontium capture: a comparative study.

PubMed

Song, Yang; Du, Yi; Lv, Dachao; Ye, Gang; Wang, Jianchen

2014-06-15

Separation of strontium is of great significance for radioactive waste treatment and environmental remediation after nuclear accidents. In this work, a novel class of adsorbent (Crown-g-MPPPs) was synthesized by chemical grafting a macrocyclic ether receptor to monodisperse porous polymer particles (MPPPs) for strontium adsorption. Meanwhile, a counterpart material (Crown@MPPPs) with the receptor molecules immobilized to the MPPPs substrate by physical impregnation was prepared. To investigate how the immobilization manner and distribution of the receptors influence the adsorption ability, a comparative study on the adsorption behaviour of the two materials towards Sr(II) in HNO3 media was accomplished. Due to the shorter diffusion path and covalently-bonded structure, Crown-g-MPPPs showed faster adsorption kinetics and better stability for cycle use. While Crown@MPPPs had the advantages of facile synthesis and higher adsorption capacity, owing to the absence of conformational constraint to form complexation with Sr(II). Kinetic functions (Lagergren pseudo-first-order/pseudo-second-order functions) and adsorption isotherm models (Langmuir/Freundlich models) were used to fit the experimental data and examine the adsorption mechanism. On this basis, a chromatographic process was proposed by using Crown@MPPPs for an effective separation of Sr(II) (91%) in simulated high level liquid waste (HLLW). Copyright © 2014 Elsevier B.V. All rights reserved.

Robust Informatics Infrastructure Required For ICME: Combining Virtual and Experimental Data

NASA Technical Reports Server (NTRS)

Arnold, Steven M.; Holland, Frederic A. Jr.; Bednarcyk, Brett A.

2014-01-01

With the increased emphasis on reducing the cost and time to market of new materials, the need for robust automated materials information management system(s) enabling sophisticated data mining tools is increasing, as evidenced by the emphasis on Integrated Computational Materials Engineering (ICME) and the recent establishment of the Materials Genome Initiative (MGI). This need is also fueled by the demands for higher efficiency in material testing; consistency, quality and traceability of data; product design; engineering analysis; as well as control of access to proprietary or sensitive information. Further, the use of increasingly sophisticated nonlinear, anisotropic and or multi-scale models requires both the processing of large volumes of test data and complex materials data necessary to establish processing-microstructure-property-performance relationships. Fortunately, material information management systems have kept pace with the growing user demands and evolved to enable: (i) the capture of both point wise data and full spectra of raw data curves, (ii) data management functions such as access, version, and quality controls;(iii) a wide range of data import, export and analysis capabilities; (iv) data pedigree traceability mechanisms; (v) data searching, reporting and viewing tools; and (vi) access to the information via a wide range of interfaces. This paper discusses key principles for the development of a robust materials information management system to enable the connections at various length scales to be made between experimental data and corresponding multiscale modeling toolsets to enable ICME. In particular, NASA Glenn's efforts towards establishing such a database for capturing constitutive modeling behavior for both monolithic and composites materials

Lack of Detection of Bt Sugarcane Cry1Ab and NptII DNA and Proteins in Sugarcane Processing Products Including Raw Sugar

PubMed Central

Cheavegatti-Gianotto, Adriana; Gentile, Agustina; Oldemburgo, Danielle Angeloni; Merheb, Graciela do Amaral; Sereno, Maria Lorena; Lirette, Ron Peter; Ferreira, Thais Helena Silva; de Oliveira, Wladecir Salles

2018-01-01

Brazil is the largest sugarcane producer and the main sugar exporter in the world. The industrial processes applied by Brazilian mills are very efficient in producing highly purified sugar and ethanol. Literature presents evidence of lack of DNA/protein in these products, regardless of the nature of sugarcane used as raw material. Recently CTNBio, the Brazilian biosafety authority, has approved the first biotechnology-derived sugarcane variety for cultivation, event CTC175-A, which expresses the Cry1Ab protein to control the sugarcane borer (Diatraea saccharalis). The event also expresses neomycin-phosphotransferase type II (NptII) protein used as selectable marker during the transformation process. Because of the high purity of sugar and ethanol produced from genetically modified sugarcane, these end-products should potentially be classified as “pure substances, chemically defined,” by Brazilian Biosafety Law No. 11.105. If this classification is to be adopted, these substances are not considered as “GMO derivatives” and fall out of the scope of Law No. 11.105. In order to assess sugar composition and quality, we evaluate Cry1Ab and NptII expression in several sugarcane tissues and in several fractions from laboratory-scale processing of event CTC175-A for the presence of these heterologous proteins as well as for the presence of traces of recombinant DNA. The results of these studies show that CTC175-A presents high expression of Cry1Ab in leaves and barely detectable expression of heterologous proteins in stalks. We also evaluated the presence of ribulose-1,5-bisphosphate carboxylase/oxygenase protein and DNA in the fractions of the industrial processing of conventional Brazilian sugarcane cultivars. Results from both laboratory and industrial processing were concordant, demonstrating that DNA and protein are not detected in the clarified juice and downstream processed fractions, including ethanol and raw sugar, indicating that protein and DNA are removed and/or degraded during processing. In conclusion, the processing of conventional sugarcane and CTC175-A Bt event results in downstream products with no detectable concentrations of heterologous DNA or new protein. These results help in the classification of sugar and ethanol derived from CTC175-A event as pure, chemically defined substances in Brazil and may relieve regulatory burdens in countries that import Brazilian sugar. PMID:29637070

Flotation of metal-loaded clay anion exchangers. Part II: the case of arsenates.

PubMed

Lazaridis, N K; Hourzemanoglou, A; Matis, K A

2002-04-01

Hydrotalcite-like materials, or otherwise termed layered double hydroxides, are clays with an ability to remove anions. As they usually are in powder form, these sorbents often present appreciable problems in the solid/liquid separation process following the sorption stage. Sorptive flotation of metal-loaded particles was investigated in this paper, as an alternative two-stage process. In the sorption process, satisfactory removals of arsenic(V) were obtained onto synthetic hydrotalcite particles from water. The effect of some parameters, like the solution ionic strength, concentrations, temperature, etc. was examined. During the second stage of the process, hydrotalcite fine particles were removed from the liquid phase by dispersed-air flotation; various surfactants were tested in relation to the ionic strength of the solution. The combined process of sorptive flotation provides promising results for arsenic removal.

Type-II GaSb/GaAs quantum-dot intermediate band with extended optical absorption range for efficient solar cells

NASA Astrophysics Data System (ADS)

Boustanji, Hela; Jaziri, Sihem

2018-02-01

GaSb/GaAs type-II quantum-dot solar cells (QD SCs) have attracted attention as highly efficient intermediate band SCs due to their infrared absorption. Type-II QDs exhibited a staggered confinement potential, where only holes are strongly confined within the dots. Long wavelength light absorption of the QDSCs is enhanced through the improved carriers number in the IB. The absorption of dots depends on their shape, material quality, and composition. Therefore, the optical properties of the GaSbGaAs QDs before and after thermal treatment are studied. Our intraband studies have shown an extended absorption into the long wavelength region 1.77 μ {m}. The annealed QDs have shown significantly more infrared response of 7.2 μ {m} compared to as-grown sample. The photon absorption and hole extraction depend strongly on the thermal annealing process. In this context, emission of holes from localized states in GaSb QDs has been studied using conductance-voltage ( G- V ) characteristics.

Process for making ceramic insulation

DOEpatents

Akash, Akash [Salt Lake City, UT; Balakrishnan, G Nair [Sandy, UT

2009-12-08

A method is provided for producing insulation materials and insulation for high temperature applications using novel castable and powder-based ceramics. The ceramic components produced using the proposed process offers (i) a fine porosity (from nano-to micro scale); (ii) a superior strength-to-weight ratio; and (iii) flexibility in designing multilayered features offering multifunctionality which will increase the service lifetime of insulation and refractory components used in the solid oxide fuel cell, direct carbon fuel cell, furnace, metal melting, glass, chemical, paper/pulp, automobile, industrial heating, coal, and power generation industries. Further, the ceramic components made using this method may have net-shape and/or net-size advantages with minimum post machining requirements.

Insert Design and Manufacturing for Foam-Core Composite Sandwich Structures

NASA Astrophysics Data System (ADS)

Lares, Alan

Sandwich structures have been used in the aerospace industry for many years. The high strength to weight ratios that are possible with sandwich constructions makes them desirable for airframe applications. While sandwich structures are effective at handling distributed loads such as aerodynamic forces, they are prone to damage from concentrated loads at joints or due to impact. This is due to the relatively thin face-sheets and soft core materials typically found in sandwich structures. Carleton University's Uninhabited Aerial Vehicle (UAV) Project Team has designed and manufactured a UAV (GeoSury II Prototype) which features an all composite sandwich structure fuselage structure. The purpose of the aircraft is to conduct geomagnetic surveys. The GeoSury II Prototype serves as the test bed for many areas of research in advancing UAV technologies. Those areas of research include: low cost composite materials manufacturing, geomagnetic data acquisition, obstacle detection, autonomous operations and magnetic signature control. In this thesis work a methodology for designing and manufacturing inserts for foam-core sandwich structures was developed. The results of this research work enables a designer wishing to design a foam-core sandwich airframe structure, a means of quickly manufacturing optimized inserts for the safe introduction of discrete loads into the airframe. The previous GeoSury II Prototype insert designs (v.1 & v.2) were performance tested to establish a benchmark with which to compare future insert designs. Several designs and materials were considered for the new v.3 inserts. A plug and sleeve design was selected, due to its ability to effectively transfer the required loads to the sandwich structure. The insert material was chosen to be epoxy, reinforced with chopped carbon fibre. This material was chosen for its combination of strength, low mass and also compatibility with the face-sheet material. The v.3 insert assembly is 60% lighter than the previous insert designs. A casting process for manufacturing the v.3 inserts was developed. The developed casting process, when producing more than 13 inserts, becomes more economical than machining. An exploratory study was conducted looking at the effects of dynamic loading on the v.3 insert performance. The results of this study highlighted areas for improving dynamic testing of foam-core sandwich structure inserts. Correlations were developed relating design variables such as face-sheet thickness and insert diameter to a failure load for different load cases. This was done through simulations using Computer Aided Engineering (CAE) software, and experimental testing. The resulting correlations were integrated into a computer program which outputs the required insert dimensions given a set of design parameters, and load values.

78 FR 70326 - Rigging Equipment for Material Handling; Extension of the Office of Management and Budget's (OMB...

Federal Register 2010, 2011, 2012, 2013, 2014

2013-11-25

...OSHA solicits public comments concerning its proposal to extend the OMB approval of the information collection requirements contained in paragraphs (b)(1), (b)(6)(i), (b)(6)(ii), (c)(15)(ii), (e)(1)(i), (ii), and (iii) and (f)(2) of the Standard on Rigging Equipment for Material Handling (29 CFR 1926.251). These paragraphs require affixing identification tags or markings on rigging equipment, developing and maintaining inspection records, and retaining proof- testing certificates.

A family of acetato-diphenoxo triply bridged dimetallic Zn(II)Ln(III) complexes: SMM behavior and luminescent properties.

PubMed

Oyarzabal, Itziar; Artetxe, Beñat; Rodríguez-Diéguez, Antonio; García, JoséÁngel; Seco, José Manuel; Colacio, Enrique

2016-06-21

Eleven dimetallic Zn(II)-Ln(III) complexes of the general formula [Zn(µ-L)(µ-OAc)Ln(NO3)2]·CH3CN (Ln(III) = Pr (1), Nd (2), Sm (3), Eu (4), Gd (5), Tb (6), Dy (7), Ho (8), Er (9), Tm (10), Yb (11)) have been prepared in a one-pot reaction from the compartmental ligand N,N'-dimethyl-N,N'-bis(2-hydroxy-3-formyl-5-bromo-benzyl)ethylenediamine (H2L). In all these complexes, the Zn(II) ions occupy the internal N2O2 site whereas the Ln(III) ions show preference for the O4 external site. Both metallic ions are bridged by an acetate bridge, giving rise to triple mixed diphenoxido/acetate bridged Zn(II)Ln(III) compounds. The Nd, Dy, Er and Yb complexes exhibit field induced single-ion magnet (SIM) behaviour, with Ueff values ranging from 14.12 to 41.55 K. The Er complex shows two relaxation processes, but only the second relaxation process with an energy barrier of 21.0 K has been characterized. The chromophoric L(2-) ligand is able to act as an "antenna" group, sensitizing the near-infrared (NIR) Nd(III) and Yb(III)-based luminescence in complexes 2 and 11 and therefore, both compounds can be considered as magneto-luminescent materials. In addition, the Sm(III), Eu(III) and Tb(III) derivatives exhibit characteristic emissions in the visible region.

Rapid thermal processing for production of chalcopyrite thin films for solar cells: Design, analysis, and experimental implementation

NASA Astrophysics Data System (ADS)

Lovelett, Robert J.

The direct conversion of solar energy to electricity, or photovoltaic energy conversion, has a number of environmental, social, and economic advantages over conventional electricity generation from fossil fuels. Currently, the most commonly-used material for photovoltaics is crystalline silicon, which is now produced at large scale and silicon-based devices have achieved power conversion efficiencies over 25% However, alternative materials, such as inorganic thin films, offer a number of advantages including the potential for lower manufacturing costs, higher theoretical efficiencies, and better performance in the field. One of these materials is the chalcopyrite Cu(InGa)(SeS) 2, which has demonstrated module efficiencies over 17% and cell efficiencies over 22%. Cu(InGa)(SeS)2 is now in the early stages of commercialization using a precursor reaction process referred to as a "selenization/sulfization" reaction. The precursor reaction process is promising because it has demonstrated high efficiency along with the large area (approximately 1 m2) uniformity that is required for modules. However, some challenges remain that limit the growth of the chalcopyrite solar cell industry including: slow reactions that limit process throughput, a limited understanding of complex reaction kinetics and transport phenomena that affect the through-film composition, and the use of highly toxic H2Se in the reaction process. In this work, I approach each of these challenges. First, to improve process throughput, I designed and implemented a rapid thermal processing (RTP) reactor, whereby the samples are heated by a 1000 W quartz-halogen lamp that is capable of fast temperature ramps and high temperature dwells. With the reactor in place, however, achieving effective temperature control in the thin film material system is complicated by two intrinsic process characteristics: (i) the temperature of the Cu(InGa)(SeS)2 film cannot be measured directly, which leaves the system without complete state feedback; and (ii), the process is significantly nonlinear due to the dominance of radiative heat transfer at high temperatures. Therefore, I developed a novel control system using a first principles-based observer and a specialized temperature controller. Next, to understand the complex kinetics governing the selenization/sulfization processes, a stochastic model of solid state reaction kinetics was developed and applied to the system. The model is capable of predicting several important phenomena observed experimentally, including steep through-film gradients in gallium mole fraction. Furthermore, the model is mathematically general and can be useful for understanding a number of solid state reaction systems. Finally, the RTP system was then used to produce and characterize chalcopyrite films using two general methods: (i) single stage and multi stage reactions in H2Se and H2S, and (ii), reaction of a selenium "capped" precursor in H2S, where selenium was deposited on the precursor by thermal evaporation and the use of toxic H2Se was avoided. It was found that the processing conditions could be used to control material properties including relative sulfur incorporation, crystallinity, and through-film gallium and sulfur profiles. Films produced using the selenium-capped precursor reaction process were used to fabricate solar cell devices using a Mo/Cu(InGa)(SeS)2/CdS/ZnO/ITO substrate device structure, and the devices were tested by measuring the current-voltage characteristic under standard conditions. Devices with approximately 10% efficiency were obtained over a range of compositions and the best device obtained in this work had an efficiency of 12.7%.

Sorption of As(V) on aluminosilicates treated with Fe(II) nanoparticles.

PubMed

Dousová, Barbora; Grygar, Tomás; Martaus, Alexandr; Fuitová, Lucie; Kolousek, David; Machovic, Vladimír

2006-10-15

Adsorption of arsenic on clay surfaces is important for the natural and simulated removal of arsenic species from aqueous environments. In this investigation, three samples of clay minerals (natural metakaoline, natural clinoptilolite-rich tuff, and synthetic zeolite) in both untreated and Fe-treated forms were used for the sorption of arsenate from model aqueous solution. The treatment of minerals consisted of exposing them to concentrated solution of Fe(II). Within this process the mineral surface has been laden with Fe(III) oxi(hydroxides) whose high affinity for the As(V) adsorption is well known. In all investigated systems the sorption capacity of Fe(II)-treated sorbents increased significantly in comparison to the untreated material (from about 0.5 to >20.0 mg/g, which represented more than 95% of the total As removal). The changes of Fe-bearing particles in the course of treating process and subsequent As sorption were investigated by the diffuse reflectance spectroscopy and the voltammetry of microparticles. IR spectra of treated and As(V)-saturated solids showed characteristic bands caused by Fe(III)SO(4), Fe(III)O, and AsO vibrations. In untreated As(V)-saturated solids no significant AsO vibrations were observed due to the negligible content of sorbed arsenate.

A novel route for the removal of bodily heavy metal lead (II)

NASA Astrophysics Data System (ADS)

Huang, Weirong; Zhang, Penghua; Xu, Hui; Chang, Shengli; He, Yongju; Wang, Fei; Liang, Gaowei

2015-09-01

The lead ion concentration in bile is considerably higher than in blood, and bile is released into the alimentary tract. Thiol-modified SBA-15 administered orally can combine with lead ions in the alimentary tract. In this paper, the in vitro lead absorption of bile was investigated. This thiol-modified SBA-15 material was used in pharmacodynamics studies on rabbits. The result that the lead content in faeces was notably higher indicates that thiol-modified SBA-15 can efficiently remove lead. The mechanism could include the following: thiol-modified SBA-15 material cuts off the heavy metal lead recirculation in the process of bile enterohepatic circulation by chelating the lead in the alimentary tract, causing a certain proportion of lead to be removed by the thiol mesoporous material, and the lead is subsequently egested out of the body in faeces. The results indicate that this material might be a potential non-injection material for the removal bodily heavy metal lead in the alimentary tract. This material may also be a useful means of lead removal, especially for non-acute sub-poisoning symptoms.

Synthesis and luminescence properties of cinnamide based nanohybrid materials containing Eu (II) ions

NASA Astrophysics Data System (ADS)

Kiran Kumar, A. B. V.; Jayasimhadri, M.; Cha, Hyeongrae; Chen, Kuangcai; Lim, Jae-Min; Lee, Yong-Ill

2011-07-01

In the present work, the cinnamide based organic-inorganic hybrid luminescent materials were prepared by using sol-gel technique, in which both the components are covalently linked via Si-C bonds. The organic precursor N-(3-(triethoxysilyl)propyl)cinnamide (Cn-Si) was synthesized by (3-aminopropyl) triethoxysilane being reacted with cinnamoyal chloride. Finally, novel hybrid materials were prepared successfully through hydrolysis and polycondensation processes between the alkoxide groups of precursors Cn-Si and tetraethylorthosilane (TEOS) in the presence of europium nitrate. We have characterized thoroughly the prepared samples using FT-IR, thermal analysis (TGA/DTA), X-ray diffraction (XRD), field emission scanning electron microscopy (FESEM), transmission electron microscopy (TEM), energy-dispersive spectroscopy (EDS) and photoluminescence (PL) spectroscopy. The results indicate that these materials exhibit the excellent thermal stability up to 350 °C. The X-ray diffraction patterns confirmed the amorphous nature of the developed materials. The rare-earth doped hybrid materials have exhibited an intense green emission at 530 nm with CIE chromaticity coordinates (0.4801, 0.4669). Whereas, the un-doped one gives some remarkable blue emission properties under UV excitation.

Mo/Si multilayers with enhanced TiO II- and RuO II-capping layers

NASA Astrophysics Data System (ADS)

Yulin, Sergiy; Benoit, Nicolas; Feigl, Torsten; Kaiser, Norbert; Fang, Ming; Chandhok, Manish

2008-03-01

The lifetime of Mo/Si multilayer-coated projection optics is one of the outstanding issues on the road of commercialization of extreme-ultraviolet lithography (EUVL). The application of Mo/Si multilayer optics in EUVL requires both sufficient radiation stability and also the highest possible normal-incidence reflectivity. A serious problem of conventional high-reflective Mo/Si multilayers capped by silicon is the considerable degradation of reflective properties due to carbonization and oxidation of the silicon surface layer under exposure by EUV radiation. In this study, we focus on titanium dioxide (TiO II) and ruthenium dioxide (RuO II) as promising capping layer materials for EUVL multilayer coatings. The multilayer designs as well as the deposition parameters of the Mo/Si systems with different capping layers were optimized in terms of maximum peak reflectivity at the wavelength of 13.5 nm and longterm stability under high-intensive irradiation. Optimized TiO II-capped Mo/Si multilayer mirrors with an initial reflectivity of 67.0% presented a reflectivity drop of 0.6% after an irradiation dose of 760 J/mm2. The reflectivity drop was explained by the partial oxidation of the silicon sub-layer. No reflectivity loss after similar irradiation dose was found for RuO II-capped Mo/Si multilayer mirrors having initial peak reflectivity of 66%. In this paper we present data on improved reflectivity of interface-engineered TiO II- and RuO II-capped Mo/Si multilayer mirrors due to the minimization of both interdiffusion processes inside the multilayer stack and absorption loss in the oxide layer. Reflectivities of 68.5% at the wavelength of 13.4 nm were achieved for both TiO II- and RuO II-capped Mo/Si multilayer mirrors.

Smaller-lateral-size graphene oxide hydrosols sealed in dialysis bags for enhanced trace Pb(II) removal from water without re-pollution

NASA Astrophysics Data System (ADS)

Guo, Lanyu; Liu, Liyun; Zhuo, Mingpeng; Fu, Shulei; Xu, Yunpeng; Zhou, Wenwei; Shi, Ce; Ye, Bin; Li, Yongxiu; Chen, Weifan

2018-07-01

In this work, presented is a novel and facile strategy to enhance Pb(II) adsorption capacity of graphene oxide (GO) hydrosols via the modified Hummers' method, using the smaller-sized natural flake graphite as starting materials. The as-prepared micron GO (MGO) and submicron GO (SMGO) hydrosols were sealed in dialysis bags for adsorptive separation of Pb(II) from water to avoid secondary pollution. The effects of pH and contact duration on Pb(II) adsorption on MGO and SMGO as well as their thermodynamics and kinetics were investigated comparatively. Their performances for recycling and regeneration were also evaluated. The results indicated that SMGO exhibited an enhanced maximum sorption capacity for Pb(II) up to 1162.60 mg·g-1 higher than MGO by 25.75% and achieved adsorption equilibrium faster, which can be attributed to the fact that SMGO has more oxygen-containing functional groups on the sheet basal planes and especially at the sheet edges than SMGO. The adsorption of Pb(II) on MGO and SMGO was a spontaneous and endothermic process and well fitted the pseudo-second-order kinetics and the Langmuir sorption model. Significantly, MGO and SMGO nanosheets still kept the high sorption capacities of 514.26 mg·g-1 and 700.35 mg·g-1 after the 5 cycles, respectively, promising of enormous potential applications.

Combined Mode I and Mode II Fracture of Plasma-Sprayed Thermal Barrier Coatings at Ambient and Elevated Temperatures

NASA Technical Reports Server (NTRS)

Choi, Sung R.; Zhu, Dongming; Miller, Robert A.

2003-01-01

The mode I, mode II, and combined mode I-mode II fracture behavior of ZrO2- 8wt%Y2O3 thermal barrier coatings was determined in asymmetric flexure loading at both ambient and elevated temperatures. Precracks were introduced in test specimens using the single-edge-v-notched beam (SEVNB) method incorporated with final diamond polishing to achieve sharp crack tips. A fracture envelope of KI versus KII was determined for the coating material at ambient and elevated temperatures. Propagation angles of fracture as a function of K(sub I)/K(sub II) were also determined. The mixed-mode fracture behaviors of the coating material were compared with those of monolithic advanced ceramics determined previously. The mixed-mode fracture behavior of the plasma-sprayed thermal barrier coating material was predicted in terms of fracture envelope and propagation angle using mixed-mode fracture theories.

Graphitization in Carbon MEMS and Carbon NEMS

NASA Astrophysics Data System (ADS)

Sharma, Swati

Carbon MEMS (CMEMS) and Carbon NEMS (CNEMS) are an emerging class of miniaturized devices. Due to the numerous advantages such as scalable manufacturing processes, inexpensive and readily available precursor polymer materials, tunable surface properties and biocompatibility, carbon has become a preferred material for a wide variety of future sensing applications. Single suspended carbon nanowires (CNWs) integrated on CMEMS structures fabricated by electrospinning of SU8 photoresist on photolithographially patterned SU8 followed by pyrolysis are utilized for understanding the graphitization process in micro and nano carbon materials. These monolithic CNW-CMEMS structures enable the fabrication of very high aspect ratio CNWs of predefined length. The CNWs thus fabricated display core---shell structures having a graphitic shell with a glassy carbon core. The electrical conductivity of these CNWs is increased by about 100% compared to glassy carbon as a result of enhanced graphitization. We explore various tunable fabrication and pyrolysis parameters to improve graphitization in the resulting CNWs. We also suggest gas-sensing application of the thus fabricated single suspended CNW-CMEMS devices by using the CNW as a nano-hotplate for local chemical vapor deposition. In this thesis we also report on results from an optimization study of SU8 photoresist derived carbon electrodes. These electrodes were applied to the simultaneous detection of traces of Cd(II) and Pb(II) through anodic stripping voltammetry and detection limits as low as 0.7 and 0.8 microgL-1 were achieved. To further improve upon the electrochemical behavior of the carbon electrodes we elucidate a modified pyrolysis technique featuring an ultra-fast temperature ramp for obtaining bubbled porous carbon from lithographically patterned SU8. We conclude this dissertation by suggesting the possible future works on enhancing graphitization as well as on electrochemical applications

Timing of Expansions of the Quelccaya Ice Cap, Peru, and Implications for Cosmogenic Nuclide Production Rate Calibration

NASA Astrophysics Data System (ADS)

Lowell, T. V.; Kelly, M. A.; Applegate, P. J.; Smith, C. A.; Phillips, F. M.; Hudson, A. M.

2010-12-01

We calibrate the production rate of the cosmogenic nuclide beryllium-10 (10Be) at a low-latitude, high-elevation site, using nuclide concentrations measured in moraine boulders and an independent chronology determined with bracketing radiocarbon dates. The measurement of terrestrial cosmogenic nuclide (TCN) concentrations in earth surface materials has been an important development for understanding a host of earth surface processes. Uncertainty in cosmogenic nuclide production rates has hampered application of this method. Here, we contribute to the estimation of 10Be production rates by reporting both preliminary 10Be concentrations and independent radiocarbon dates from a low latitude, high elevation site. Our study site in the southeastern Peruvian Andes (~13.9°S, 70.9°W, 4850 m asl) is centered on a moraine set, known as the Huancané II moraines, that represents a ~4 km expansion of Quelccaya Ice Cap during late glacial time. At this location, organic material situated both stratigraphically below and above moraines in two adjacent valleys provide material for radiocarbon dating. Based on geomorphic arguments, we correlate results from the two valleys. The timing of ice cap margin advance is bracketed by 13 radiocarbon ages on organic material within the outermost Huancané II moraines that range from 13.6 to 12.5 ka. Two stratigraphic sections upvalley from the moraines yield 6 radiocarbon ages from 11.3 to 12.4 ka, indicating the time of retreat . We computed the probability density function that lies between these two sets of dates, and assign an age of 12.4 ka (+/-???) for the formation of the Huancané II moraines. Calculating beryllium-10 exposure dates from the measured concentrations yield exposure dates that significantly underestimate the independently determined age of the moraine (~8-30%), if existing production rate estimates are used. We suggest that the radiocarbon age for the moraines can be used as a robust independent calibration for 10Be production rates at this site.

Preparation of chitosan/MCM-41-PAA nanocomposites and the adsorption behaviour of Hg(II) ions

NASA Astrophysics Data System (ADS)

Fu, Yong; Huang, Yue; Hu, Jianshe

2018-03-01

A novel functional hybrid mesoporous composite material (CMP) based on chitosan and MCM-41-PAA was reported and its application as an excellent adsorbent for Hg(II) ions was also investigated. Innovatively, MCM-41-PAA was prepared by using diatomite and polyacrylic acid (PAA) with integrated polymer-silica hybrid frameworks, and then CMP was fabricated by introducing MCM-41-PAA to chitosan using glutaraldehyde as a cross-linking agent. The structure and morphology of CMP were characterized by X-ray diffraction, Fourier transform infrared spectra, thermogravimetric analysis, scanning electron microscopy and Brunauer-Emmett-Teller measurements. The results showed that the CMP possessed multifunctional groups such as -OH, -COOH and -NH2 with large specific surface area. Adsorption behaviour of Hg(II) ions onto CMP was fitted better by the pseudo-second-order kinetic model and the Langmuir model when the initial Hg(II) concentration, pH, adsorption temperature and time were 200 mg l-1, 4, 298 K and 120 min, respectively, as the optimum conditions. The corresponding maximum adsorption capacity could reach 164 mg g-1. According to the thermodynamic parameters determined such as free energy, enthalpy and entropy, the adsorption process of Hg(II) ions was spontaneous endothermic adsorption.

Preparation of chitosan/MCM-41-PAA nanocomposites and the adsorption behaviour of Hg(II) ions

PubMed Central

Fu, Yong; Huang, Yue; Hu, Jianshe

2018-01-01

A novel functional hybrid mesoporous composite material (CMP) based on chitosan and MCM-41-PAA was reported and its application as an excellent adsorbent for Hg(II) ions was also investigated. Innovatively, MCM-41-PAA was prepared by using diatomite and polyacrylic acid (PAA) with integrated polymer–silica hybrid frameworks, and then CMP was fabricated by introducing MCM-41-PAA to chitosan using glutaraldehyde as a cross-linking agent. The structure and morphology of CMP were characterized by X-ray diffraction, Fourier transform infrared spectra, thermogravimetric analysis, scanning electron microscopy and Brunauer–Emmett–Teller measurements. The results showed that the CMP possessed multifunctional groups such as –OH, –COOH and –NH2 with large specific surface area. Adsorption behaviour of Hg(II) ions onto CMP was fitted better by the pseudo-second-order kinetic model and the Langmuir model when the initial Hg(II) concentration, pH, adsorption temperature and time were 200 mg l−1, 4, 298 K and 120 min, respectively, as the optimum conditions. The corresponding maximum adsorption capacity could reach 164 mg g−1. According to the thermodynamic parameters determined such as free energy, enthalpy and entropy, the adsorption process of Hg(II) ions was spontaneous endothermic adsorption. PMID:29657793

Monitoring of trace amounts of heavy metals in different food and water samples by flame atomic absorption spectrophotometer after preconcentration by amine-functionalized graphene nanosheet.

PubMed

Behbahani, Mohammad; Tapeh, Nasim Akbari Ghareh; Mahyari, Mojtaba; Pourali, Ali Reza; Amin, Bahareh Golrokh; Shaabani, Ahmad

2014-11-01

We are introducing graphene oxide modified with amine groups as a new solid phase for extraction of heavy metal ions including cadmium(II), copper(II), nickel(II), zinc(II), and lead(II). Effects of pH value, flow rates, type, concentration, and volume of the eluent, breakthrough volume, and the effect of potentially interfering ions were studied. Under optimized conditions, the extraction efficiency is >97 %, the limit of detections are 0.03, 0.05, 0.2, 0.1, and 1 μg L(-1) for the ions of cadmium, copper, nickel, zinc, and lead, respectively, and the adsorption capacities for these ions are 178, 142, 110, 125, and 210 mg g(-1). The amino-functionalized graphene oxide was characterized by thermogravimetric analysis, transmission electron microscopy, scanning electron microscopy, and Fourier transform infrared spectrometry. The proposed method was successfully applied in the analysis of environmental water and food samples. Good spiked recoveries over the range of 95.8-100.0 % were obtained. This work not only proposes a useful method for sample preconcentration but also reveals the great potential of modified graphene as an excellent sorbent material in analytical processes.

Cervical and Incisal Marginal Discrepancy in Ceramic Laminate Veneering Materials: A SEM Analysis

PubMed Central

Ranganathan, Hemalatha; Ganapathy, Dhanraj M.; Jain, Ashish R.

2017-01-01

Context: Marginal discrepancy influenced by the choice of processing material used for the ceramic laminate veneers needs to be explored further for better clinical application. Aims: This study aimed to evaluate the amount of cervical and incisal marginal discrepancy associated with different ceramic laminate veneering materials. Settings and Design: This was an experimental, single-blinded, in vitro trial. Subjects and Methods: Ten central incisors were prepared for laminate veneers with 2 mm uniform reduction and heavy chamfer finish line. Ceramic laminate veneers fabricated over the prepared teeth using four different processing materials were categorized into four groups as Group I - aluminous porcelain veneers, Group II - lithium disilicate ceramic veneers, Group III - lithium disilicate-leucite-based veneers, Group IV - zirconia-based ceramic veneers. The cervical and incisal marginal discrepancy was measured using a scanning electron microscope. Statistical Analysis Used: ANOVA and post hoc Tukey honest significant difference (HSD) tests were used for statistical analysis. Results: The cervical and incisal marginal discrepancy for four groups was Group I - 114.6 ± 4.3 μm, 132.5 ± 6.5 μm, Group II - 86.1 ± 6.3 μm, 105.4 ± 5.3 μm, Group III - 71.4 ± 4.4 μm, 91.3 ± 4.7 μm, and Group IV - 123.1 ± 4.1 μm, 142.0 ± 5.4 μm. ANOVA and post hoc Tukey HSD tests observed a statistically significant difference between the four test specimens with regard to cervical marginal discrepancy. The cervical and incisal marginal discrepancy scored F = 243.408, P < 0.001 and F = 180.844, P < 0.001, respectively. Conclusion: This study concluded veneers fabricated using leucite reinforced lithium disilicate exhibited the least marginal discrepancy followed by lithium disilicate ceramic, aluminous porcelain, and zirconia-based ceramics. The marginal discrepancy was more in the incisal region than in the cervical region in all the groups. PMID:28839415

Cervical and Incisal Marginal Discrepancy in Ceramic Laminate Veneering Materials: A SEM Analysis.

PubMed

Ranganathan, Hemalatha; Ganapathy, Dhanraj M; Jain, Ashish R

2017-01-01

Marginal discrepancy influenced by the choice of processing material used for the ceramic laminate veneers needs to be explored further for better clinical application. This study aimed to evaluate the amount of cervical and incisal marginal discrepancy associated with different ceramic laminate veneering materials. This was an experimental, single-blinded, in vitro trial. Ten central incisors were prepared for laminate veneers with 2 mm uniform reduction and heavy chamfer finish line. Ceramic laminate veneers fabricated over the prepared teeth using four different processing materials were categorized into four groups as Group I - aluminous porcelain veneers, Group II - lithium disilicate ceramic veneers, Group III - lithium disilicate-leucite-based veneers, Group IV - zirconia-based ceramic veneers. The cervical and incisal marginal discrepancy was measured using a scanning electron microscope. ANOVA and post hoc Tukey honest significant difference (HSD) tests were used for statistical analysis. The cervical and incisal marginal discrepancy for four groups was Group I - 114.6 ± 4.3 μm, 132.5 ± 6.5 μm, Group II - 86.1 ± 6.3 μm, 105.4 ± 5.3 μm, Group III - 71.4 ± 4.4 μm, 91.3 ± 4.7 μm, and Group IV - 123.1 ± 4.1 μm, 142.0 ± 5.4 μm. ANOVA and post hoc Tukey HSD tests observed a statistically significant difference between the four test specimens with regard to cervical marginal discrepancy. The cervical and incisal marginal discrepancy scored F = 243.408, P < 0.001 and F = 180.844, P < 0.001, respectively. This study concluded veneers fabricated using leucite reinforced lithium disilicate exhibited the least marginal discrepancy followed by lithium disilicate ceramic, aluminous porcelain, and zirconia-based ceramics. The marginal discrepancy was more in the incisal region than in the cervical region in all the groups.

Optimized Extraction, Preliminary Characterization, and In Vitro Antioxidant Activity of Polysaccharides from Glycyrrhiza Uralensis Fisch

PubMed Central

Chen, Jie; Li, Wan-chen; Gu, Xin-li

2017-01-01

Background This study performed optimized extraction, preliminary characterization, and in vitro antioxidant activities of polysaccharides from Glycyrrhiza uralensis Fisch. Material/Methods Three parameters (extraction temperature, ratio of water to raw material, and extraction time) were optimized for yields of G. uralensis polysaccharides (GUP) using response surface methodology with Box-Behnken design (BBD). The GUP was purified using DEAE cellulose 32-column chromatography. The main fraction obtained from G. uralensis Fisch was GUP-II, which was composed of rhamnose, arabinose, galactose, and glucose monosaccharide, was screened for antioxidant properties using DP Hand hydroxyl radical scavenging assays. In addition, immunological activity of GUP-II was determined by nitric oxide and lymphocyte proliferation assays. Results Optimization revealed maximum GUP yields with an extraction temperature of 99°C, water: raw material ratio of 15: 1, and extraction duration of 2 h. GUP-II purified from G. uralensis Fisch had good in vitro DPPH and hydroxyl radical scavenging abilities. Immunologically, GUP-II significantly stimulated NO production in RAW 264.7 macrophages, and significantly enhanced LPS-induced lymphocyte proliferation. Conclusions Extraction of GUP from G. uralensis Fisch can be optimized with respect to temperature, extraction period, and ratio of water to material, using response surface methodology. The purified product (GUP-II) possesses excellent antioxidant and immunological activities. PMID:28404983

Doorways II: Community Counselor Reference Materials. On School-Related Gender-Based Violence Prevention and Response

ERIC Educational Resources Information Center

US Agency for International Development, 2009

2009-01-01

The Doorways training program was designed by the U.S. Agency for International Development (USAID)-funded Safe Schools Program (Safe Schools) to enable teachers, community members and students to prevent and respond to school-related gender-based violence (SRGBV). This booklet, "Doorways II: Community Counselor Reference Materials on…

Utilization of protein-rich residues in biotechnological processes.

PubMed

Pleissner, Daniel; Venus, Joachim

2016-03-01

A drawback of biotechnological processes, where microorganisms convert biomass constituents, such as starch, cellulose, hemicelluloses, lipids, and proteins, into wanted products, is the economic feasibility. Particularly the cost of nitrogen sources in biotechnological processes can make up a large fraction of total process expenses. To further develop the bioeconomy, it is of considerable interest to substitute cost-intensive by inexpensive nitrogen sources. The aim of this mini-review was to provide a comprehensive insight of utilization methods of protein-rich residues, such as fish waste, green biomass, hairs, and food waste. The methods described include (i) production of enzymes, (ii) recovery of bioactive compounds, and/or (iii) usage as nitrogen source for microorganisms in biotechnological processes. In this aspect, the utilization of protein-rich residues, which are conventionally considered as waste, allows the development of value-adding processes for the production of bioactive compounds, biomolecules, chemicals, and materials.

Heterobimetallic porphyrin complexes displaying triple dynamics: coupled metal motions controlled by constitutional evolution.

PubMed

Le Gac, Stéphane; Fusaro, Luca; Roisnel, Thierry; Boitrel, Bernard

2014-05-07

A bis-strap porphyrin ligand (1), with an overhanging carboxylic acid group on each side of the macrocycle, has been investigated toward the formation of dynamic libraries of bimetallic complexes with Hg(II), Cd(II), and Pb(II). Highly heteroselective metalation processes occurred in the presence of Pb(II), with Hg(II) or Cd(II) bound out-of-plane to the N-core and "PbOAc" bound to a carboxylate group of a strap on the opposite side. The resulting complexes, 1(Hg)·PbOAc and 1(Cd)·PbOAc, display three levels of dynamics. The first is strap-level (interactional dynamics), where the PbOAc moiety swings between the left and right side of the strap owing to a second sphere of coordination with lateral amide functions. The second is ligand-level (motional dynamics), where 1(Hg)·PbOAc and 1(Cd)·PbOAc exist as two degenerate states in equilibrium controlled by a chemical effector (AcO(-)). The process corresponds to a double translocation of the metal ions according to an intramolecular migration of Hg(II) or Cd(II) through the N-core, oscillating between the two equivalent overhanging carbonyl groups, coupled to an intermolecular pathway for PbOAc exchanging between the two equivalent overhanging carboxylate groups (N-core(up) ⇆ N-core(down) coupled to strap(down) ⇆ strap(up), i.e., coupled motion #1 in the abstract graphic). The third is library-level (constitutional dynamics), where a dynamic constitutional evolution of the system was achieved by the successive addition of two chemical effectors (DMAP and then AcO(-)). It allowed shifting equilibrium forward and backward between 1(Hg)·PbOAc and the corresponding homobimetallic complexes 1(Hg2)·DMAP and 1(Pb)·PbOAc. The latter displays a different ligand-level dynamics, in the form of an intraligand coupled migration of the Pb(II) ions (N-core(up) ⇆ strap(up) coupled to strap(down) ⇆ N-core(down), i.e., coupled motion #2 in the abstract graphic). In addition, the neutral "bridged" complexes 1HgPb and 1CdPb, with the metal ions on opposite sides both bound to the N-core and to a carboxylate of a strap, were structurally characterized. These results establish an unprecedented approach in supramolecular coordination chemistry, by considering the reversible interaction of a metal ion with the porphyrin N-core as a new source of self-organization processes. This work should provide new inspirations for the design of innovative adaptative materials and devices.

Randomized clinical trial of two resin-modified glass ionomer materials: 1-year results.

PubMed

Perdigão, J; Dutra-Corrêa, M; Saraceni, S H C; Ciaramicoli, M T; Kiyan, V H

2012-01-01

With institutional review board approval, 33 patients who needed restoration of noncarious cervical lesions (NCCL) were enrolled in this study. A total of 92 NCCL were selected and randomly assigned to three groups: (1) Ambar (FGM), a two-step etch-and-rinse adhesive (control), combined with the nanofilled composite resin Filtek Supreme Plus (FSP; 3M ESPE); (2) Fuji II LC (GC America), a traditional resin-modified glass ionomer (RMGIC) restorative material; (3) Ketac Nano (3M ESPE), a nanofilled RMGIC restorative material. Restorations were evaluated at six months and one year using modified United States Public Health Service parameters. At six months after initial placement, 84 restorations (a 91.3% recall rate) were evaluated. At one year, 78 restorations (a 84.8% recall rate) were available for evaluation. The six month and one year overall retention rates were 93.1% and 92.6%, respectively, for Ambar/FSP; 100% and 100%, respectively, for Fuji II LC; and 100% and 100%, respectively, for Ketac Nano with no statistical difference between any pair of groups at each recall. Sensitivity to air decreased for all three adhesive materials from the preoperative to the postoperative stage, but the difference was not statistically significant. For Ambar/FSP, there were no statistical differences for any of the parameters from baseline to six months and from baseline to one year. For Fuji II LC, surface texture worsened significantly from baseline to six months and from baseline to one year. For Ketac Nano, enamel marginal staining increased significantly from baseline to one year and from six months to one year. Marginal adaptation was statistically worse at one year compared with baseline only for Ketac Nano. When parameters were compared for materials at each recall, Ketac Nano resulted in significantly worse color match than any of the other two materials at any evaluation period. At one year, Ketac Nano resulted in significantly worse marginal adaptation than the other two materials and worse marginal staining than Fuji II LC. Surface texture was statistically worse for Fuji II LC compared with the other two materials at all evaluation periods. The one-year retention rate was statistically similar for the three adhesive materials. Nevertheless, enamel marginal deficiencies and color mismatch were more prevalent for Ketac Nano. Surface texture of Fuji II LC restorations deteriorated quickly.

Structure-Property-Environmental Relations in Glass and Glass-Ceramics.

DTIC Science & Technology

1980-03-01

dense Al203 result in a deep surface layer of preferred orientation detection by RKS methods. ii: C Mv CL.ASSIFICAIC S . e .. fa " " p h D e TABLE OF...distribution and decreases the isoelectric point of the powders. Variations in processing of dense Al 203 result in a deep surface layer of preferred...by their surfaces, it is essential that we learn how to predict the surface chemistry of these materials in order to optimize their performance. The

Synergistic effect of graphene oxide on the methanol oxidation for fuel cell application

NASA Astrophysics Data System (ADS)

Siwal, Samarjeet; Ghosh, Sarit; Nandi, Debkumar; Devi, Nishu; Perla, Venkata K.; Barik, Rasmita; Mallick, Kaushik

2017-09-01

Aromatic polypyrene was synthesized by the oxidative polymerization of pyrene with potassium tetrachloropalladate (II), as oxidant. During the polymerization process the palladium salt was reduced to metallic palladium and forms the metal-polymer composite material. Polypyrene stabilized palladium nanoparticles showed electrocatalytic activity toward the oxidation of methanol. The performance of the electrocatalytic activity was substantially improved with the incorporation of graphene oxide to the palladium-polypyrene composite and the synergistic performance was attributed to the electronic and structural properties of the system.

DARPA - Advanced Composite Materials Annual Presentation Held in Gainesville, Florida on 19-20 November 1992

DTIC Science & Technology

1992-11-20

34 and M.D. Sacks 13) "Fabrication of SiC -Based Composites by Reactive Infiltration of Metals (RIM)" K. Wang," G.W. Scheiffele, P.J. Sanchez-Soto, and...Ig I I keactive Infiltration of Metals (RIM) Ii * Densification with little or no shrinkage e SIC -based composites with little or no residual metal...M.D. Sacks I) Indicates Presenter Intermetallic: Matrix Composites 14) *Processing of Compositionally Tailored Silica-Free MoSi 2/ SiC Composites ’ S

Copper(II)-catalyzed oxidative [3+2] cycloaddition reactions of secondary amines with α-diazo compounds: a facile and efficient synthesis of 1,2,3-triazoles.

PubMed

Li, Yi-Jin; Li, Xue; Zhang, Shao-Xiao; Zhao, Yu-Long; Liu, Qun

2015-07-25

A novel copper-catalyzed [3+2] cycloaddition reaction of secondary amines with α-diazo compounds has been developed via a cross-dehydrogenative coupling process. The reaction involves a sequential aerobic oxidation/[3+2] cycloaddition/oxidative aromatization procedure and provides an efficient method for the construction of 1,2,3-triazoles in a single step in an atom-economic manner from readily available starting materials under very mild conditions.

Client-Side Data Processing and Training for Multispectral Imagery Applications in the GOES-R Era

NASA Technical Reports Server (NTRS)

Fuell, Kevin; Gravelle, Chad; Burks, Jason; Berndt, Emily; Schultz, Lori; Molthan, Andrew; Leroy, Anita

2016-01-01

RGB imagery can be created locally (i.e. client-side) from single band imagery already on the system with little impact given recommended change to texture cache in AWIPS II. Training/Reference material accessible to forecasters within their operational display system improves RGB interpretation and application as demonstrated at OPG. Application examples from experienced forecasters are needed to support the larger community use of RGB imagery and these can be integrated into the user's display system.

Refining of Military Jet Fuels from Shale Oil. Volume I. Part II. Preparation of Laboratory-Scale Fuel Samples.

DTIC Science & Technology

1982-03-01

ON SPEC Meeting Specifications *1 OXY Test Series on In Situ Shale Oil P Pressure (P + N) Paraffins and Naphthenes PHO Test Series on Above-Ground...material, the crude shale is heated and processed through caustic desalt- ing similar to conventional technology. The desalted oil is mixed with recycle...with hot regenerated catalyst. Spent catalyst and oil vapors are disengaqed by -.eans of high temperature cyclones. The spent catalyst first passes

Advanced Antireflection Coatings for High-Performance Solar Energy Applications

NASA Technical Reports Server (NTRS)

Pan, Noren

2015-01-01

Phase II objectives: Develop and refine antireflection coatings incorporating lanthanum titanate as an intermediate refractive index material; Investigate wet/dry thermal oxidation of aluminum containing semiconductor compounds as a means of forming a more transparent window layer with equal or better optical properties than its unoxidized form; Develop a fabrication process that allows integration of the oxidized window layer and maintains the necessary electrical properties for contacting the solar cell; Conduct an experimental demonstration of the best candidates for improved antireflection coatings.

Technical Basis Document for Internal Dosimetry at Sandia National Laboratories Revision 2.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Potter, Charles A.

2014-09-01

The RPID Project will be implemented at all SNL facilities for activities involving the processing and/or storing of radioactive materials. This project includes activities at the Tech Area (TA) I, TA II, TA III, TA IV, TA V, Coyote Test Field, and environmental restoration sites at SNL, located in Albuquerque, New Mexico, and the Kauai Test Facility(SNL/KTF). Reference to SNL throughout this document includes facilities and activities at the Albuquerque location and at SNL/KTF.

77 FR 64142 - Importer of Controlled Substances, Notice of Application, Noramco, Inc.

Federal Register 2010, 2011, 2012, 2013, 2014

2012-10-18

... following basic classes of controlled substances: Drug Schedule Phenylacetone (8501) II Opium, raw (9600) II Poppy Straw Concentrate (9670) II Tapentadol (9780) II The company plans to import raw Opium (9600) and... substance. Comments and requests for hearings on applications to import narcotic raw material are not...

Chromium and zinc uptake by algae Gelidium and agar extraction algal waste: kinetics and equilibrium.

PubMed

Vilar, Vítor J P; Botelho, Cidália M S; Boaventura, Rui A R

2007-11-19

Biosorption of chromium and zinc ions by an industrial algal waste, from agar extraction industry has been studied in a batch system. This biosorbent was compared with the algae Gelidium itself, which is the raw material for agar extraction, and the industrial waste immobilized with polyacrylonitrile (composite material). Langmuir and Langmuir-Freundlich equilibrium models describe well the equilibrium data. The parameters of Langmuir equilibrium model at pH 5.3 and 20 degrees C were for the algae, q(L)=18 mg Cr(III)g(-1) and 13 mgZn(II)g(-1), K(L) = 0.021l mg(-1)Cr(III) and 0.026l mg(-1) Zn(II); for the algal waste, q(L)=12 mgCr(III)g(-1) and 7mgZn(II)g(-1), K(L)=0.033lmg(-1) Cr(III) and 0.042l mg(-1) Zn(II); for the composite material, q(L) = 9 mgCr(III)g(-1) and 6 mgZn(II)g(-1), K(L)=0.032l mg(-1)Cr(III) and 0.034l mg(-1)Zn(II). The biosorbents exhibited a higher preference for Cr(III) ions and algae Gelidium is the best one. The pseudo-first-order Lagergren and pseudo-second-order models fitted well the kinetic data for the two metal ions. Kinetic constants and equilibrium uptake concentrations given by the pseudo-second-order model for an initial Cr(III) and Zn(II) concentration of approximately 100 mgl(-1), at pH 5.3 and 20 degrees C were k(2,ads)=0.04 g mg(-1)Cr(III)min(-1) and 0.07 g mg(-1)Zn(II)min(-1), q(eq)=11.9 mgCr(III)g(-1) and 9.5 mgZn(II)g(-1) for algae; k(2,ads)=0.17 g mg(-1)Cr(III)min(-1) and 0.19 g mg(-1)Zn(II)min(-1), q(eq)=8.3 mgCr(III)g(-1) and 5.6 mgZn(II)g(-1) for algal waste; k(2,ads)=0.01 g mg(-1)Cr(III)min(-1) and 0.18 g mg(-1)Zn(II)min(-1), q(eq)=8.0 mgCr(III)g(-1) and 4.4 mgZn(II)g(-1) for composite material. Biosorption was modelled using a batch adsorber mass transfer kinetic model, which successfully predicts Cr(III) and Zn(II) concentration profiles. The calculated average homogeneous diffusivities, D(h), were 4.2 x 10(-8), 8.3 x 10(-8) and 1.4 x 10(-8)cm(2)s(-1) for Cr(III) and 4.8 x 10(-8), 9.7 x 10(-8) and 6.2 x 10(-8)cm(2)s(-1) for Zn(II), respectively, for Gelidium, algal waste and composite material. The algal waste has the lower intraparticle resistance.

77 FR 19717 - Importer of Controlled Substances; Notice of Registration Mallinckrodt LLC

Federal Register 2010, 2011, 2012, 2013, 2014

2012-04-02

... raw material are not appropriate, 72 FR 3417 (2007). Regarding all other basic classes of controlled...) II Opium, raw (9600) II Poppy Straw Concentrate (9670) II The company plans to import the listed...

77 FR 24984 - Importer of Controlled Substances; Notice of Application; Rhodes Technologies

Federal Register 2010, 2011, 2012, 2013, 2014

2012-04-26

.... Comments and requests for hearings on applications to import narcotic raw material are not appropriate. 72... schedule II: Drug Schedule Opium, Raw (9600) II Poppy Straw Concentrate (9670) II The company plans to...

78 FR 12101 - Importer of Controlled Substances; Notice of Application; Mallinckrodt, LLC.

Federal Register 2010, 2011, 2012, 2013, 2014

2013-02-21

... Coca Leaves (9040) II Opium, raw (9600) II Poppy Straw Concentrate (9670) II The company plans to... or coca leaves. Comments and requests for hearings on applications to import narcotic raw material...

Incorporation of Pyrazine and Bipyridine Linkers with High-Spin Fe(II) and Co(II) in a Metal–Organic Framework

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kawamura, Airi; Greenwood, Arin R.; Filatov, Alexander S.

2017-02-27

A series of isoreticular metal organic frameworks (MOFs) of the formula M(BDC)(L) (M = Fe(II) or Co(II), BDC = 1,4-benzenedicarboxylate, L = pyrazine (pyz) or 4,4'-bipyridine (bipy)) has been synthesized and characterized by N-2 gas uptake Measurements, single crystal and powder X-ray diffraction, magnetometry, X-ray absorption spectroscopy, and Mossbauer spectroscopy. These studies indicate the formation of a permanently porous solid with high-spin Fe(II) and Co(II) centers that are weakly coupled, consistent with first-principles density functional theory calculations. This family of materials represents unusual examples of paramagnetic metal centers coordinated by linkers capable of mediating magnetic or electronic coupling in amore » porous framework. While only weak interactions are observed, the rigid 3D framework of the MOF dramatically impacts the properties of these materials when compared with close structural analogues.« less

Study of Material Consolidation at Higher Throughput Parameters in Selective Laser Melting of Inconel 718

NASA Technical Reports Server (NTRS)

Prater, Tracie

2016-01-01

Selective Laser Melting (SLM) is a powder bed fusion additive manufacturing process used increasingly in the aerospace industry to reduce the cost, weight, and fabrication time for complex propulsion components. SLM stands poised to revolutionize propulsion manufacturing, but there are a number of technical questions that must be addressed in order to achieve rapid, efficient fabrication and ensure adequate performance of parts manufactured using this process in safety-critical flight applications. Previous optimization studies for SLM using the Concept Laser M1 and M2 machines at NASA Marshall Space Flight Center have centered on machine default parameters. The objective of this work is to characterize the impact of higher throughput parameters (a previously unexplored region of the manufacturing operating envelope for this application) on material consolidation. In phase I of this work, density blocks were analyzed to explore the relationship between build parameters (laser power, scan speed, hatch spacing, and layer thickness) and material consolidation (assessed in terms of as-built density and porosity). Phase II additionally considers the impact of post-processing, specifically hot isostatic pressing and heat treatment, as well as deposition pattern on material consolidation in the same higher energy parameter regime considered in the phase I work. Density and microstructure represent the "first-gate" metrics for determining the adequacy of the SLM process in this parameter range and, as a critical initial indicator of material quality, will factor into a follow-on DOE that assesses the impact of these parameters on mechanical properties. This work will contribute to creating a knowledge base (understanding material behavior in all ranges of the AM equipment operating envelope) that is critical to transitioning AM from the custom low rate production sphere it currently occupies to the world of mass high rate production, where parts are fabricated at a rapid rate with confidence that they will meet or exceed all stringent functional requirements for spaceflight hardware. These studies will also provide important data on the sensitivity of material consolidation to process parameters that will inform the design and development of future flight articles using SLM.

The processing and characterization of animal-derived bone to yield materials with biomedical applications. Part II: milled bone powders, reprecipitated hydroxyapatite and the potential uses of these materials.

PubMed

Johnson, G S; Mucalo, M R; Lorier, M A; Gieland, U; Mucha, H

2000-11-01

Further studies on the processing and use of animal-bone-derived calcium phosphate materials in biomedical applications are presented. Bone powders sourced either from the direct crushing and milling of bovine, ovine and cervine bone or after being subjected to defatting and acid digestion/NaOH reprecipitation and sodium hypochlorite hydrogen peroxide treatment of animal bones were characterized using Fourier transform infra-red (FTIR) spectroscopy, 13C solid state magic angle spinning (MAS) nuclear magnetic resonance (NMR) spectroscopy, atomic absorption (AA) and inductively coupled plasma (ICP) spectrometric techniques. Bone powders were trialled for their potential use as a substrate for phosphine coupling and enzyme immobilization as well as a feedstock powder for plasma spraying on titanium metal substrates. Results indicated that enzyme immobilization by phosphine coupling could be successfully achieved on milled cervine bone with the immobilized enzyme retaining some activity. It was found that the presence of impurities normally carried down with the processing of the bone materials (viz., fat and collagen) played an important role in influencing the adsorbency and reactivity of the powders. Plasma spraying studies using reprecipitated bovine-derived powders produced highly adherent coatings on titanium metal, the composition of which was mostly hydroxyapatite (Ca10(PO4)6(OH)2) with low levels of alpha-tricalcium phosphate (alpha-Ca3(PO4)2) and tetracalcium phosphate (Ca4P2O9) also detected. In general, animal derived calcium phosphate materials constitute a potentially cheaper source of calcium phosphate materials for biomedical applications and make use of a largely under-utilized resource from abattoir wastes. Copyright 2000 Kluwer Academic Publishers

Interfacial reactions between humic-like substances and lateritic clay: application to the preparation of "geomimetic" materials.

PubMed

Goure-Doubi, Herve; Martias, Céline; Lecomte-Nana, Gisèle Laure; Nait-Ali, Benoît; Smith, Agnès; Thune, Elsa; Villandier, Nicolas; Gloaguen, Vincent; Soubrand, Marilyne; Konan, Léon koffi

2014-11-15

The aim of this study was to understand the mechanisms responsible for the strengthening of "geomimetic" materials, especially the chemical bonding between clay and humic substances. The mineral matter is lateritic clay which mainly consists in kaolinite, goethite, hematite and quartz. The other starting products are fulvic acid (FA) and lime. The preparation of these geomimetic materials is inspired from the natural stabilization of soils by humic substances occurring over thousands of years. The present process involves acidic and alkaline reactions followed by a curing period of 18days at 60°C under a water saturated atmosphere. The acceleration of the strengthening process usually observed in soils makes this an original process for treatment of soils. The consolidation of the "geomimetic" materials could result from two major phenomena: (i) chemical bonding at the interface between the clay particles and iron compounds and the functional groups of the fulvic acid, (ii) a partial dissolution of the clay grains followed by the precipitation of the cementitious phases, namely calcium silicate hydrates, calcium aluminate hydrates and mixed calcium silicum and aluminum hydrates. Indeed, the decrease of the BET specific area of the lateritic clay after 24 h of reaction with FA added to the structural reorganization observed between 900 and 1000°C in the "geomimetic" material, and to the results of adsorption measurements, confirm the formation of organo-ferric complexes. The presence of iron oxides in clay, in the form of goethite, appears to be another parameter in favor of a ligand exchange process and the creation of binding bridges between FA and the mineral matter. Indeed all faces of goethite are likely to be involved in complexation reactions whereas in lateritic clay only lateral faces could be involved. The results of the adsorption experiments realized at a local scale will improve our understandings about the process of adsorption of FA on lateritic clays and its involvement in the strengthening process of materials. Copyright © 2014 Elsevier Inc. All rights reserved.

A new photocatalytic reactor for trace contaminant control: a water polishing system.

PubMed

Gonzalez-Martin, A; Kim, J; Van Hyfte, J; Rutherford, L A; Andrews, C

2001-01-01

In spacecraft water recovery systems there is a need to develop a postprocessor water polishing system to remove organic impurities to levels below 250 micrograms/L (ppb) with a minimum use of expendables. This article addresses the development of a photocatalytic process as a postprocessor water polishing system that is microgravity compatible, operates at room temperature, and requires only a minimal use of both oxygen gas (or air) and electrical power for low energy UV-A (315-400 nm) lamps. In the photocatalytic process, organic contaminants are degraded to benign end products on semiconductor surfaces, usually TiO2. Some challenging issues related to the use of TiO2 for the degradation of organic contaminants have been addressed. These include: i) efficient and stable catalytic material; ii) immobilization of the catalyst to produce a high surface area material that can be used in packed-bed reactors, iii) effective light penetration, iv) effective, microgravity-compatible, oxidant delivery; v) reduced pressure drop, and vi) minimum retention time. The research and development performed on this photocatalytic process is presented in detail. Grant numbers: NAS9-97182.

Preparation and properties of a calcium(II)-based molecular chain decorated with manganese(II) butterfly-like complexes.

PubMed

Benniston, A C; Melnic, S; Turta, C; Arauzo, A B; Bartolomé, J; Bartolomé, E; Harrington, R W; Probert, M R

2014-09-21

The room temperature reaction of [Mn2O2(bipy)4](ClO4)3 (bipy = 2,2'-bipyridine) with Ca(CHCl2COO)2 in methanol produced a yellow crystalline material. The X-ray determined structure comprises of a multiple calcium(II) carboxylate bridged chain-like structure which is decorated with [Mn(bipy)2(OH2)](2+) subunits. The redox behaviour for the complex in H2O and MeCN is reported. In the latter solvent the oxidation of the manganese ions appears to be facilitated by the presence of the calcium ions. Magnetic susceptibility and low temperature magnetization measurements show that the Mn moment is isotropic, with g = 1.99(1) and S = 5/2, confirming it is in the 2+ oxidation state. A very weak antiferromagnetic interaction is also detected. Frequency-dependent ac measurements evidence slow magnetic relaxation of the Mn(bipy)2 units. Two relaxation mechanisms are identified: a very slow direct process and a faster one caused by the Resonant Phonon Trapping mechanism. This is the first example of field-induced single ion magnet (SIM) behavior in a mononuclear Mn(II) complex.

Effects of bite-jumping appliances on mandibular advancement in growing rats: A radiographic study

PubMed Central

Oksayan, Ridvan; Sokucu, Oral; Ucuncu, Neslihan

2014-01-01

Objective: The aim was to evaluate the effects of the use of mandibular advancement appliances on mandibular growth in growing rats. Materials and Methods: Twenty-four 8-week-old male Wistar albino rats were randomly divided into two experimental groups (12 rats each): Group I was a control group, and Group II was the mandibular advancement appliance group. A functional bite-jumping appliance was used in Group II to promote mandibular advancement. Anatomical changes in the condyle and mandible were evaluated by comparing radiographic results from before and after the study, with angular and linear measurements. Friedman and Mann-Whitney U-tests were used in statistical analysis. Results: According to the radiographic results, the growth of mandibles and condyles in Group II was significantly greater than with the length of the condylar process (A-B) and distance from condyle to menton (A-D) variables (P < 0.05). In addition, Group I showed greater mandibular base growth than did Group II (P < 0.05). Conclusions: We conclude that the use of an intraoral bite-jumping appliance can stimulate condylar growth and increase sagittal mandibular advancement in growing rats. PMID:25202205

Ultraviolet Spectroscopy of Tidal Disruption Flares

NASA Astrophysics Data System (ADS)

Cenko, Stephen B.

2017-08-01

When a star passes within the sphere of disruption of a massive black hole, tidal forces will overcome self-gravity and unbind the star. While approximately half of the stellar debris is ejected at high velocities, the remaining material stays bound to the black hole and accretes, resulting in a luminous, long-lived transient known as a tidal disruption flare (TDF). In addition to serving as unique laboratories for accretion physics,TDFs offer the hope of measuring black hole masses in galaxies much too distant for resolved kinematic studies.In order to realize this potential, we must better understand the detailed processes by which the bound debris circularizes and forms an accretion disk. Spectroscopy is critical to this effort, as emission and absorption line diagnostics provide insight into the location and physical state (velocity, density, composition) of the emitting gas (in analogy with quasars). UV spectra are particularly critical, as most strong atomic features fall in this bandpass, and high-redshift TDF discoveries from LSST will sample rest-frame UV wavelengths.Here I present recent attempts to obtain UV spectra of tidal disruption flares. I describe the UV spectrum of ASASSN-14li, in which we detect three classes of features: narrow absorption from the Milky Way (probably a high-velocity cloud), and narrow absorption and broad (2000-8000 km s-1) emission lines at or near the systemic host velocity. The absorption lines are blueshifted with respect to the emission lines by 250-400 km s-1. Due both to this velocity offset and the lack of common low-ionization features (Mg II, Fe II), we argue these arise from the same absorbing material responsible for the low-velocity outflow discovered at X-ray wavelengths. The broad nuclear emission lines display a remarkable abundance pattern: N III], N IV], and He II are quite prominent, while the common quasar emission lines of C III] and Mg II are weak or entirely absent. Detailed modeling of this spectrum will help elucidate fundamental questions regarding the nature of the emission processes at work in TDFs, while future UV spectroscopy of ASASSN-14li would help to confirm (or refute) the previously proposed connection between TDFs and “N-rich” quasars.

Co(II)-doped MOF-5 nano/microcrystals: Solvatochromic behaviour, sensing solvent molecules and gas sorption property

DOE Office of Scientific and Technical Information (OSTI.GOV)

Yang, Ji-Min; School of Chemistry and Chemical Engineering, Linyi University, Linyi 276005; Liu, Qing

2014-10-15

Co(II)-doped MOF-5 nano/microcrystals with controllable morphology and size were successfully obtained by solvothermal method. The products were characterized by powder X-ray diffraction (PXRD), energy dispersive spectrometry (EDS), field emission scanning electron microscopy (FESEM), thermogravimetric analysis (TGA), inductively coupled plasma optical emission spectrometer (ICP-OES), elemental analysis, UV–vis and infrared (IR) spectroscopy. The factors influencing the crystal morphology and size were investigated. The gas sorption measurements reveal that highly crystalline particles have large Langmuir surface area. It was found that the Co(II)-doped MOF-5 shows enhanced hydrostability and the sorption profiles of the Co(II)-doped MOF-5 nano/microcrystals are dependent on the morphology and sizemore » of the particles. Porous Co(II)-doped MOF-5 is stable upon the removal of guest molecules and exhibits different colour with accommodating different solvent molecule, which means that it can act as solvatochromic sensing materials for recognition of solvent molecules. - Graphical abstract: Co(II)-doped MOF-5 nano/microcrystals with different shapes and sizes were synthesized by a facile hydrothermal method, which not only enhance gas sorption properties and structural stability of MOFs towards moisture, but also act as new sensing materials for sensing small molecules. - Highlights: • Co(II)-doped MOF-5 nano/microcrystals with controllable morphology and size were obtained. • Co(II)-doped MOF-5 nano/microcrystals enhance the structural stability towards moisture. • Co(II)-doped MOF-5 can act as new sensing material for sensing small molecules.« less

Pathogenetic role of Factor VII deficiency and thrombosis in cross-reactive material positive patients.

PubMed

Girolami, A; Sambado, L; Bonamigo, E; Ferrari, S; Lombardi, A M

2013-12-01

Congenital Factor VII (FVII) deficiency can be divided into two groups: cases of "true" deficiency, or cross-reactive material (CRM) negative and variants that are cross-reactive material positive.The first form is commonly recognized as Type I condition whereas the second one is known as Type II. FVII deficiency has been occasionally associated with thrombotic events, mainly venous. The reasons underlying this peculiar manifestation are unknown even though in the majority of associated patients thrombotic risk factors are present. The purpose of the present study was to investigate if a thrombotic event was more frequent in Type I or in Type II defect.The majority of patients with FVII deficiency and thrombosis belong to Type II defects. In the following paper we discuss the possible role of the dysfunctional FVII cross-reaction material as a contributory cause for the occurrence of thrombosis.

An r-process enhanced star in the dwarf galaxy Tucana III

DOE PAGES

Hansen, T. T.; Simon, J. D.; Marshall, J. L.; ...

2017-03-20

Chemically peculiar stars in dwarf galaxies provide a window for exploring the birth environment of stars with varying chemical enrichment. We present a chemical abundance analysis of the brightest star in the newly discovered ultra-faint dwarf galaxy candidate Tucana III. Because it is particularly bright for a star in an ultra-faint Milky Way (MW) satellite, we are able to measure the abundance of 28 elements, including 13 neutron-capture species. This star, DES J235532.66–593114.9 (DES J235532), shows a mild enhancement in neutron-capture elements associated with the r-process and can be classified as an r-I star. DES J235532 is the first r-Imore » star to be discovered in an ultra-faint satellite, and Tuc III is the second extremely low-luminosity system found to contain r-process enriched material, after Reticulum II. Comparison of the abundance pattern of DES J235532 with r-I and r-II stars found in other dwarf galaxies and in the MW halo suggests a common astrophysical origin for the neutron-capture elements seen in all r-process enhanced stars. Furthermore, we explore both internal and external scenarios for the r-process enrichment of Tuc III and show that with abundance patterns for additional stars, it should be possible to distinguish between them.« less

An r-process enhanced star in the dwarf galaxy Tucana III

DOE Office of Scientific and Technical Information (OSTI.GOV)

Hansen, T. T.; Simon, J. D.; Marshall, J. L.

Chemically peculiar stars in dwarf galaxies provide a window for exploring the birth environment of stars with varying chemical enrichment. We present a chemical abundance analysis of the brightest star in the newly discovered ultra-faint dwarf galaxy candidate Tucana III. Because it is particularly bright for a star in an ultra-faint Milky Way (MW) satellite, we are able to measure the abundance of 28 elements, including 13 neutron-capture species. This star, DES J235532.66–593114.9 (DES J235532), shows a mild enhancement in neutron-capture elements associated with the r-process and can be classified as an r-I star. DES J235532 is the first r-Imore » star to be discovered in an ultra-faint satellite, and Tuc III is the second extremely low-luminosity system found to contain r-process enriched material, after Reticulum II. Comparison of the abundance pattern of DES J235532 with r-I and r-II stars found in other dwarf galaxies and in the MW halo suggests a common astrophysical origin for the neutron-capture elements seen in all r-process enhanced stars. Furthermore, we explore both internal and external scenarios for the r-process enrichment of Tuc III and show that with abundance patterns for additional stars, it should be possible to distinguish between them.« less

Stainless Steel to Titanium Bimetallic Transitions

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kaluzny, J. A.; Grimm, C.; Passarelli, D.

In order to use stainless steel piping in an LCLS-II (Linac Coherent Light Source Upgrade) cryomodule, stainless steel to titanium bimetallic transitions are needed to connect the stainless steel piping to the titanium cavity helium vessel. Explosion bonded stainless steel to titanium transition pieces and bimetallic transition material samples have been tested. A sample transition tube was subjected to tests and x-ray examinations between tests. Samples of the bonded joint material were impact and tensile tested at room temperature as well as liquid helium temperature. The joint has been used successfully in horizontal tests of LCLS-II cavity helium vessels andmore » is planned to be used in LCLS-II cryomodules. Results of material sample and transition tube tests will be presented.« less

77 FR 24983 - Importer of Controlled Substances; Notice of Application Penick Corporation

Federal Register 2010, 2011, 2012, 2013, 2014

2012-04-26

... import narcotic raw material are not appropriate. 72 FR 3417(2007). As noted in a previous notice... Schedule Coca Leaves (9040) II Raw Opium (9600) II Poppy Straw (9650) II Concentrate of Poppy Straw (9670...

Comparison of physical properties of regenerated cellulose films fabricated with different cellulose feedstocks in ionic liquid.

PubMed

Pang, JinHui; Wu, Miao; Zhang, QiaoHui; Tan, Xin; Xu, Feng; Zhang, XueMing; Sun, RunCang

2015-05-05

With the serious "white pollution" resulted from the non-biodegradable plastic films, considerable attention has been directed toward the development of renewable and biodegradable cellulose-based film materials as substitutes of petroleum-derived materials. In this study, environmentally friendly cellulose films were successfully prepared using different celluloses (pine, cotton, bamboo, MCC) as raw materials and ionic liquid 1-ethyl-3-methylimidazolium acetate as a solvent. The SEM and AFM indicated that all cellulose films displayed a homogeneous and smooth surface. In addition, the FT-IR and XRD analysis showed the transition from cellulose I to II was occurred after the dissolution and regeneration process. Furthermore, the cellulose films prepared by cotton linters and pine possessed the most excellent thermal stability and mechanical properties, which were suggested by the highest onset temperature (285°C) and tensile stress (120 MPa), respectively. Their excellent properties of regenerated cellulose films are promising for applications in food packaging and medical materials. Copyright © 2014 Elsevier Ltd. All rights reserved.