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Last update: August 15, 2014.
1

Preparation of Fibrous Palladium.  

National Technical Information Service (NTIS)

Acrylic fibers (pan fibers) absorb palladium from a hot solution of palladium nitrate in nitric acid. When palladium-loaded acrylic fibers are burned, fibers consisting of palladium and palladium oxide are formed. Reduction of this mixture with hydrogen p...

G. L. Silver P. W. Seabaugh B. T. Leahy D. W. Werkmeister F. S. Martin

1988-01-01

2

The semiconductivity and stability of palladium oxide  

Microsoft Academic Search

Palladium metal films are prepared on quartz substrates by RF sputtering from a pure palladium target in an argon atmosphere. These films are then oxidized in air or in an oxygen atmosphere at 700 C for periods between 24 hr and 6 days. Either treatment is found to produce good-quality thin films of PdO with a uniform orange transmission. Attention

E. Rey; R. B. Miles; B. S. H. Royce; M. R. Kamal

1978-01-01

3

Final Hazard Categorization for the Remediation of the 118-D-1, 118-D-2, 118-D-3, 118-H-1, 118-H-2, and 118-H-3 Solid Waste Burial Grounds  

SciTech Connect

This report presents the final hazard categorization (FHC) for the remediation of the 118-D-1, 118-D-2, and 118-D-3 Burial Grounds located within the 100-D/DR Area of the Hanford Site and the 118-H-1, 118-H-2, and 118-H-3 Burial Grounds located within the 100-H Area of the Hanford Site.

T. J. Rodovsky

2006-12-06

4

Final Hazard Categorization for the Remediation of the 118-D-1, 118-D-2, 118-D-3, 118-H-1, 118-H-2 and 118-H-3 Solid Waste Burial Grounds  

SciTech Connect

This report presents the final hazard categorization for the remediation of the 118-D-1, 118-D-2, and 118-D-3 Burial Grounds located within the 100-D/DR Area of the Hanford Site and the 118-H-1, 118-H-2, and 118-H-3 Burial Grounds located within the 100-H Area of the Hanford Site.

K. L. Vialetti

2008-05-20

5

Final Hazard Categorization for the Remediation of the 118-D-1, 118-D-2, 118-D-3, 118-H-1, 118-H-2, and 118-H-3 Solid Waste Burial Grounds  

SciTech Connect

This report presents the final hazard categorization (FHC) for the remediation of the 118-D-1, 118-D-2, and 118-D-3 Burial Grounds located within the 100-D/DR Area of the Hanford Site and the 118-H-1, 118-H-2, and 118-H-3 Burial Grounds located within the 100-H Area of the Hanford Site.

T. J. Rodovsky

2007-04-12

6

Final Hazard Categorization and Auditable Safety Analysis for the Remediation of the 118-D-1, 118-D-2, 118-D-3, 118-H-1, 118-H-2 and 118-H-3 Solid Waste Burial Grounds  

SciTech Connect

This report presents the initial hazard categorization, final hazard categorization and auditable safety analysis for the remediation of the 118-D-1, 118-D-2, and 118-D-3 Burial Grounds located within the 100-D/DR Area of the Hanford Site and the 118-H-1, 118-H-2, and 118-H-3 Burial Grounds located within the 100-H Area of the Hanford Site.

T. J. Rodovsky

2006-03-01

7

Final Hazard Categorization for the Remediation of the 118-D-1, 118-D-2, 118-D-3, 118-H-1, 118-H-2, and 118-H-3 Solid Waste Burial Grounds  

SciTech Connect

This report presents the final hazard categorization for the remediation of the 118-D-1, 118-D-2, 118-D-3 Burial Grounds located within the 100-D/DR Area of the Hanford Site and the 118-H-1, 118-H-2, and 118-H-3 Burial Grounds located within the 100-H Area of the Hanford Site. A material at risk calculation was performed that determined the radiological inventory for each burial ground to be Hazard Category 3.

J.D. Ludowise

2009-06-17

8

45 CFR 400.118 - Case planning.  

Code of Federal Regulations, 2013 CFR

...118 Section 400.118 Public Welfare OFFICE OF REFUGEE RESETTLEMENT, ADMINISTRATION FOR CHILDREN AND FAMILIES, DEPARTMENT OF HEALTH...REFUGEE RESETTLEMENT PROGRAM Child Welfare Services § 400.118 Case...

2013-10-01

9

Mechanism of Action of a Palladium Modifier on Atomization Processes  

NASA Astrophysics Data System (ADS)

We have demonstrated a desorption mechanism for dissipation of palladium from a palladium modifier in a graphite furnace during sample atomization. We have carried out mathematical modeling with the aim of obtaining the most important kinetic parameters of the atomization processes: diffusion rate and energy of formation of free atoms. The energy of formation of free silver atoms in the presence of palladium, calculated from the shape of the signals, increases from 118.5 ± 6.3 to 199.5 ± 8.4 kJ/mol, while the activation energy for diffusion of silver in the graphite of the furnace walls increases from 75.6 ± 1.1 to 135.2 ± 6.0 kJ/mol, which suggests direct chemical reaction between palladium and silver.

Rogulsky, Yu. V.; Illiashenko, V. Yu.; Kulik, A. N.

2014-01-01

10

Sputter target  

DOEpatents

The disclosure relates to an improved sputter target for use in the deposition of hard coatings. An exemplary target is given wherein titanium diboride is brazed to a tantalum backing plate using a gold-palladium-nickel braze alloy.

Gates, Willard G. (Kansas City, MO); Hale, Gerald J. (Overland Park, KS)

1980-01-01

11

Palladium on kieselguhr  

SciTech Connect

Palladium supported in kieselguhr (Pd/K) is a candidate material for processing of hydrogen isotopes at Savannah River Laboratory (SRL) and Savannah River Plant (SRP). Kieselguhr is a porous, sedimentary rock composed of silicified skeletal remains of single-celled aquatic plants called diatoms. SRL has developed a process for deposition of palladium on kieselguhr particles using immersion in an ammonical palladium chloride solution followed by heating in hydrogen to decompose the chloride to metallic palladium. The goal is to produce Pd/K particles with less than 250 ppm chlorine.

Mosley, W.C.

1988-01-11

12

29 CFR 1917.118 - Fixed ladders.  

Code of Federal Regulations, 2013 CFR

...2013-07-01 2013-07-01 false Fixed ladders. 1917.118 Section 1917...Terminal Facilities § 1917.118 Fixed ladders. (a) Scope and applicability. This section applies to all fixed ladders except: (1)...

2013-07-01

13

46 CFR 118.300 - Fire pumps.  

Code of Federal Regulations, 2013 CFR

...Shipping 4 2013-10-01 2013-10-01 false Fire pumps. 118.300 Section 118.300 Shipping...OVERNIGHT ACCOMMODATIONS FOR MORE THAN 49 PASSENGERS FIRE PROTECTION EQUIPMENT Fire Main System § 118.300 Fire pumps....

2013-10-01

14

INNOVATIONS IN PALLADIUM MEMBRANE RESEARCH  

Microsoft Academic Search

This review highlights various aspects of current palladium membrane research and serves as a comprehensive bibliography covering palladium membrane preparation methods and applications. There are many promising uses for palladium membranes, although widespread use of the available technologies is constrained primarily by the high cost of palladium, lack of durability due to hydrogen embrittlement, and susceptibility to fouling. Various researchers

S. N. Paglieri

2002-01-01

15

Electroless Palladium Deposition.  

National Technical Information Service (NTIS)

Electroless deposition of palladium was achieved from solutions utilizing hypophosphite as reducing agent at temperatures from 30 to 70C. Electroless palladium deposits contain about 1.5 per cent phosphorus and have a Vickers hardness of about 165 kg/sq m...

F. Pearlstein R. F. Weightman

1969-01-01

16

STS-118 Radiator Impact Damage  

NASA Technical Reports Server (NTRS)

During the August 2007 STS-118 mission to the International Space Station, a micro-meteoroid or orbital debris (MMOD) particle impacted and completely penetrated one of shuttle Endeavour s radiator panels and the underlying thermal control system (TCS) blanket, leaving deposits on (but no damage to) the payload bay door. While it is not unusual for shuttle orbiters to be impacted by small MMOD particles, the damage from this impact is larger than any previously seen on the shuttle radiator panels. A close-up photograph of the radiator impact entry hole is shown in Figure 1, and the location of the impact on Endeavour s left-side aft-most radiator panel is shown in Figure 2. The aft radiator panel is 0.5-inches thick and consists of 0.011 inch thick aluminum facesheets on the front and back of an aluminum honeycomb core. The front facesheet is additionally covered by a 0.005 inch thick layer of silver-Teflon thermal tape. The entry hole in the silver-Teflon tape measured 8.1 mm by 6.4 mm (0.32 inches by 0.25 inches). The entry hole in the outer facesheet measured 7.4 mm by 5.3 mm (0.29 inches by 0.21 inches) (0.23 inches). The impactor also perforated an existing 0.012 inch doubler that had been bonded over the facesheet to repair previous impact damage (an example that lightning can strike the same place twice, even for MMOD impact). The peeled-back edge around the entry hole, or lip , is a characteristic of many hypervelocity impacts. High velocity impact with the front facesheet fragmented the impacting particle and caused it to spread out into a debris cloud. The debris cloud caused considerable damage to the internal honeycomb core with 23 honeycomb cells over a region of 28 mm by 26 mm (1.1 inches by 1.0 inches) having either been completely destroyed or partially damaged. Figure 3 is a view of the exit hole in the rear facesheet, and partially shows the extent of the honeycomb core damage and clearly shows the jagged petaled exit hole through the backside facesheet. The rear facesheet exit hole damage including cracks in the facesheet measures 14 mm by 14 mm (0.55 inches by 0.55 inches). The remnants of the impacting particle and radiator panel material blown through the rear facesheet hole also created two penetrations in the TCS blanket 115 mm (4.5 inches) behind the rear facesheet. Figure 4 shows these two impacts, which are located 75 mm (3 inches) apart. Some deposits of material were found on the payload bay door beneath the TCS blanket, but no additional damage occurred to the door. Figure 5 illustrates the relationship of the facesheet entry hole to the TCS blanket damage, which may indicate the direction of the impacting particle. The image on the left side of Figure 5 shows an overhead view of the damaged radiator after the facesheet holes were cored out of the panel. The entry hole location and the two underlying TCS blanket damage sites are annotated on the image. Section A-A, running through the entry hole and TCS blanket damage locations, describes a 25 angle from the longitudinal axis of the shuttle. The 2nd impact angle can be seen in section A-A on the right side of Figure 5. An average 17 angle of impact to the surface normal was derived by measuring the angles of the two damage sites in TCS blanket to the entry hole.

Lear, Dana M.; Hyde, J.; Christiansen, E.; Herrin, J.; Lyons, F.

2008-01-01

17

7 CFR 4280.118 - Insurance requirements.  

...SERVICE AND RURAL UTILITIES SERVICE, DEPARTMENT OF AGRICULTURE LOANS AND GRANTS Rural Energy for America Program General Renewable Energy System and Energy Efficiency Improvement Grants § 4280.118 Insurance requirements. Agency...

2014-01-01

18

Dasycladus ramosus, WNC2005-118  

NSDL National Science Digital Library

WNC2005-118, Dasycladus ramosus Chamberlain, intertidal, Jesser Point, Sodwana Bay, Kwazulu-Natal, South Africa, collection SA05-070, 18 Aug 2005, Coll: Brooke Stuercke, Det: B Stuercke & DW Freshwater, voucher for Fritz's study 1 of 2

Freshwater, Wilson

2008-03-07

19

Experimental study on cold fusion using deuterium gas and deuterium ion beam with palladium  

NASA Astrophysics Data System (ADS)

A series of experiments using deuterium gas and low energy deuteron beam with palladium has been designed at Mississippi State University to allow for the observation, if it exists, of cold fusion. Three experiments were performed. One involved the diffusion transient of deuterium gas into palladium. The gas was cooled by liquid nitrogen, and its temperature was permitted to rise to room temperature, changing from near -34°C to 19°C in 75 minutes. A spherical lithium neutron detector, 21 cm from the palladium, gave an audible indication of neutron levels approximately twice the background. A second experiment used a deuterium ion beam (1 kev) which bombarded a palladium target. An average counting rate of 36±6 counts for 2 minutes was measured by a BF3 tube with a paraffin moderator, 50 cm from the target. The background varied from 1-7 counts for each 2 minutes of counting period and averaged 4±2 counts in 2 minutes. A nitrogen ion beam impinging on the same palladium target produced 6 counts for a 2-minute counting period. A third experiment used a hydrogen ion beam first, then a nitrogen ion beam, finally a deuterium ion beam to bombard the same palladium target. These ion beams had energy less than 1 kev, and created neutron counts in the range of background. The palladium specimens were a piece of foil and a tube which used to be the palladium leak in a neutron generator. These preliminary experiments will be repeated, improved, and extended later.

Gu, Albert G.; Teng, Robert K. F.; Miller, Mark S.; Sprouse, Jeff

1990-09-01

20

Palladium nanowire hydrogen sensor  

Microsoft Academic Search

Palladium nanowires, synthesized by template-nanomanufacturing techniques, has been studied for hydrogen gas sensing applications at room temperature. In this study parallel arrays of Pd nanowires were fabricated by electrodeposition from an aqueous plating solution onto an HOPG surface. The nanowires were then transferred onto a polystyrene film and silver electrical contact pads were fabricated by shadow masking. The morphology of

Deep Banerji; Massood Z. Atashbar; Srikanth Singamaneni

2003-01-01

21

47 CFR 15.118 - Cable ready consumer electronics equipment.  

Code of Federal Regulations, 2010 CFR

...2010-10-01 false Cable ready consumer electronics equipment. 15.118 Section 15.118...Radiators § 15.118 Cable ready consumer electronics equipment. (a) All consumer electronics TV receiving equipment marketed in...

2010-10-01

22

47 CFR 15.118 - Cable ready consumer electronics equipment.  

Code of Federal Regulations, 2010 CFR

...2009-10-01 false Cable ready consumer electronics equipment. 15.118 Section 15.118...Radiators § 15.118 Cable ready consumer electronics equipment. (a) All consumer electronics TV receiving equipment marketed in...

2009-10-01

23

33 CFR 118.90 - Bridges crossing channel obliquely.  

Code of Federal Regulations, 2013 CFR

...Waters 1 2013-07-01 2013-07-01 false Bridges crossing channel obliquely. 118.90 Section 118...Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY BRIDGES BRIDGE LIGHTING AND OTHER SIGNALS § 118.90 Bridges...

2013-07-01

24

48 CFR 1371.118 - Changes-ship repair.  

Code of Federal Regulations, 2010 CFR

...2010-10-01 2010-10-01 false Changes-ship repair. 1371.118 Section 1371.118 Federal...DEPARTMENT SUPPLEMENTAL REGULATIONS ACQUISITIONS INVOLVING SHIP CONSTRUCTION AND SHIP REPAIR Provisions and Clauses 1371.118...

2010-10-01

25

48 CFR 1371.118 - Changes-ship repair.  

Code of Federal Regulations, 2011 CFR

...2011-10-01 2011-10-01 false Changes-ship repair. 1371.118 Section 1371.118 Federal...DEPARTMENT SUPPLEMENTAL REGULATIONS ACQUISITIONS INVOLVING SHIP CONSTRUCTION AND SHIP REPAIR Provisions and Clauses 1371.118...

2011-10-01

26

48 CFR 1371.118 - Changes-ship repair.  

Code of Federal Regulations, 2012 CFR

...2012-10-01 2012-10-01 false Changes-ship repair. 1371.118 Section 1371.118 Federal...DEPARTMENT SUPPLEMENTAL REGULATIONS ACQUISITIONS INVOLVING SHIP CONSTRUCTION AND SHIP REPAIR Provisions and Clauses 1371.118...

2012-10-01

27

48 CFR 1371.118 - Changes-ship repair.  

Code of Federal Regulations, 2013 CFR

...2013-10-01 2013-10-01 false Changes-ship repair. 1371.118 Section 1371.118 Federal...DEPARTMENT SUPPLEMENTAL REGULATIONS ACQUISITIONS INVOLVING SHIP CONSTRUCTION AND SHIP REPAIR Provisions and Clauses 1371.118...

2013-10-01

28

46 CFR 118.115 - Applicability; preemptive effect.  

Code of Federal Regulations, 2013 CFR

...2013-10-01 false Applicability; preemptive effect. 118.115 Section 118...Provisions § 118.115 Applicability; preemptive effect. (a) Except as otherwise...The regulations in this part have preemptive effect over State or local...

2013-10-01

29

28 CFR 115.118 - Upgrades to facilities and technologies.  

Code of Federal Regulations, 2013 CFR

...facilities and technologies. 115.118 Section 115.118 Judicial Administration DEPARTMENT OF JUSTICE (CONTINUED) PRISON RAPE ELIMINATION ACT NATIONAL STANDARDS Standards for Lockups Prevention Planning § 115.118 Upgrades to facilities and...

2013-07-01

30

The semiconductivity and stability of palladium oxide  

NASA Technical Reports Server (NTRS)

Palladium metal films are prepared on quartz substrates by RF sputtering from a pure palladium target in an argon atmosphere. These films are then oxidized in air or in an oxygen atmosphere at 700 C for periods between 24 hr and 6 days. Either treatment is found to produce good-quality thin films of PdO with a uniform orange transmission. Attention is focused on optical and electrical conductivity measurements made on PdO films with a view toward determining their band gap, conductivity and thermal stability in vacuum and in the presence of oxygen. It is shown that hydrogen greatly reduces the thermal stability of PdO. The film decomposes to Pd metal by 350 K in the presence of hydrogen as compared to a temperature of about 580 K in vacuum.

Rey, E.; Miles, R. B.; Royce, B. S. H.; Kamal, M. R.

1978-01-01

31

Development of palladium nanowires  

NASA Astrophysics Data System (ADS)

Inherent limitations of traditional lithography have prompted the search for means of achieving self-assembly of nano-scale structures and networks for the next generation of electronic and photonic devices. The nanowire, the basic building block of a nanocircuit, has recently become the focus of intense research. Reports on nanowire synthesis and assembly have appeared in the scientific literature, which include Vapor-Liquid-Solid mechanism, template-based electrochemical fabrication, solvothermal or wet chemistry, and assembly by fluid alignment or microchannel networks. An ideal approach for practical application of nanowires would circumvent technical and economic constraints of templating. Here we report on the self-assembly of highly-ordered metallic nanowires directly from a palladium acetate solution under an applied alternating current (AC) electric field of relatively high intensity and frequency. DNA-templated nanowires are first presented here. DNA molecules were stretched and positioned by electric field, followed by metallization by palladium acetate solution. Palladium nanowire arrays have been found to grow directly between microelectrodes without any template, under an alternating electric field of relatively high intensity and frequency. The wires grew spontaneously along the direction of the electric field and have high uniformity and conductivity. Single 75 nm-diameter palladium nanowires have also been self-assembled from aqueous solution at predefined locations between 15 mum-gap electrodes built on a SiO2 substrate. Nanowire assembly was initiated by application an electric field, and it occurred only along the direction of field lines where the field is strongest. Related metals did not support single nanowire assembly under comparable conditions. Current-limiting circuits for controlled nanowire synthesis, electric field simulation, and growth mechanism were studied. The simple and straightforward approach to nanowire assembly outlined here will provide a means of nano-/micro-scale device interconnection at precise positions at room temperature and good potential for device development, integration, and packaging.

Cheng, Chuanding

32

Synthesis and conductivity of palladium polymethacrylate  

SciTech Connect

Synthesis of palladium polymethacrylate and its dc conductivity have been investigated. Infrared spectra of the palladium acetate and palladium polymethacrylate are taken and compared. The palladium polymethacrylate spectrum indicates that Pd is not attached with COOH, instead it forms a complex with carboxylic group. Measurements indicate that conduction in this material cannot be attributed to a single conduction process.

Chohan, M.H. (Dept. of Electronics, Quaid-i-Azam Univ., Islamagad (PK)); Khawja, F.A.; Rehamn, A.U. (Dept. of Physics, Quaid-i-Azam Univ., Islamabad (PK)); Zulfiqar, M.; Tahir, M. (Dept. of Chemistry, Quaid-i-Azam Univ., Islamabad (PK))

1991-01-20

33

Nanostructured palladium membrane synthesis by magnetron sputtering  

Microsoft Academic Search

Palladium membranes are of technological interest since they show a very high selectivity for hydrogen. Diffusion through the palladium is often the rate-limiting step in hydrogen transport through the membrane. Hydrogen flux can be improved by reducing the membrane thickness and increasing the hydrogen diffusivity. Nanostructured palladium has a higher hydrogen diffusivity than conventional palladium due to its large volume

Kenneth J. Bryden; Jackie Y. Ying

1995-01-01

34

Hydrogen absorption induced metal deposition on palladium and palladium-alloy particles  

SciTech Connect

The present invention relates to methods for producing metal-coated palladium or palladium-alloy particles. The method includes contacting hydrogen-absorbed palladium or palladium-alloy particles with one or more metal salts to produce a sub-monoatomic or monoatomic metal- or metal-alloy coating on the surface of the hydrogen-absorbed palladium or palladium-alloy particles. The invention also relates to methods for producing catalysts and methods for producing electrical energy using the metal-coated palladium or palladium-alloy particles of the present invention.

Wang, Jia X. (East Setauket, NY); Adzic, Radoslav R. (East Setauket, NY)

2009-03-24

35

Study of palladium plating components  

NASA Technical Reports Server (NTRS)

Palladium deposits were prepared by electrolysis for evaluation as catalytic materials. Electrolysis was carried out in acidic solutions consisting of either 1.0 M in NaCl and 0.01 M PdCl2 or 1.0 M NaCl and 0.04 M PdCl2. It was during the preparation of the palladium deposits that unexpected observations were made that led to the request for analytical services. The analyses did not, nor were they intended to, answer all of the questions. They did, however, shed light on the nature and magnitude of some of the contaminants in the solutions and in the palladium electrodes, as well as characterize the forms of the palladium deposits. Results of analyses are grouped into solution, deposit, and electrode categories for comparison purposes.

1977-01-01

36

46 CFR 118.410 - Fixed gas fire extinguishing systems.  

Code of Federal Regulations, 2010 CFR

...2009-10-01 2009-10-01 false Fixed gas fire extinguishing systems. 118...PASSENGERS FIRE PROTECTION EQUIPMENT Fixed Fire Extinguishing and Detecting Systems § 118.410 Fixed gas fire extinguishing systems....

2009-10-01

37

46 CFR 118.410 - Fixed gas fire extinguishing systems.  

Code of Federal Regulations, 2010 CFR

...2010-10-01 2010-10-01 false Fixed gas fire extinguishing systems. 118...PASSENGERS FIRE PROTECTION EQUIPMENT Fixed Fire Extinguishing and Detecting Systems § 118.410 Fixed gas fire extinguishing systems....

2010-10-01

38

Aromatase is phosphorylated in situ at Serine-118  

PubMed Central

Phosphorylation of the cytochrome P450 aromatase has been proposed as a switch to rapidly modulate enzymatic activity and estrogen biosynthesis. Herein, we demonstrate that aromatase serine-118 is a potential phosphorylation site in mammalian cells. The amino acid context surrounding S118 is highly conserved among diverse animal species and suggests that an AGC-like kinase may phosphorylate aromatase. Mutation of S118 to Ala blocked phosphorylation. Mutation of S118 to either Ala or Asp destabilized aromatase, indicating an important structural role for S118. The phosphomimetic S118D mutant showed decreased specific enzymatic activity, decreased Vmax, and increased Km, while the S118A phospho-inhibiting mutant showed opposite effects. Our findings suggest that phosphorylation of S118 may decrease aromatase activity, presenting a mechanism whereby kinase signaling may modulate estrogen production and hormone balance.

Miller, Todd W.; Shin, Incheol; Kagawa, Norio; Evans, Dean B.; Waterman, Michael R.; Arteaga, Carlos L.

2010-01-01

39

46 CFR 118.410 - Fixed gas fire extinguishing systems.  

Code of Federal Regulations, 2013 CFR

...2013-10-01 2013-10-01 false Fixed gas fire extinguishing systems. 118.410 Section 118...OVERNIGHT ACCOMMODATIONS FOR MORE THAN 49 PASSENGERS FIRE PROTECTION EQUIPMENT Fixed Fire Extinguishing and Detecting Systems §...

2013-10-01

40

Low-cost method for fabricating palladium and palladium-allow thin films on porous supports  

DOEpatents

A process for forming a palladium or palladium alloy membrane on a ceramic surface by forming a pre-colloid mixture comprising a powder palladium source, carrier fluid, dispersant and a pore former and a binder. Ultrasonically agitating the precolloid mixture and applying to a substrate with an ultrasonic nozzle and heat curing the coating form a palladium-based membrane.

Lee, Tae H; Park, Chan Young; Lu, Yunxiang; Dorris, Stephen E; Balachandran, Uthamalingham

2013-11-19

41

46 CFR 118.425 - Galley hood fire extinguishing systems.  

Code of Federal Regulations, 2010 CFR

...2009-10-01 2009-10-01 false Galley hood fire extinguishing systems. 118.425...Detecting Systems § 118.425 Galley hood fire extinguishing systems. (a) A grease extraction hood required by § 118.400 of this part must...

2009-10-01

42

46 CFR 118.425 - Galley hood fire extinguishing systems.  

Code of Federal Regulations, 2010 CFR

...2010-10-01 2010-10-01 false Galley hood fire extinguishing systems. 118.425...Detecting Systems § 118.425 Galley hood fire extinguishing systems. (a) A grease extraction hood required by § 118.400 of this part must...

2010-10-01

43

33 CFR 118.60 - Characteristics of lights.  

Code of Federal Regulations, 2013 CFR

...2013-07-01 2013-07-01 false Characteristics of lights. 118.60 Section 118.60 Navigation and Navigable...AND OTHER SIGNALS § 118.60 Characteristics of lights. All lights required or authorized under this part must...

2013-07-01

44

46 CFR 118.310 - Fire main and hydrants.  

Code of Federal Regulations, 2013 CFR

...Shipping 4 2013-10-01 2013-10-01 false Fire main and hydrants. 118.310 Section 118.310...OVERNIGHT ACCOMMODATIONS FOR MORE THAN 49 PASSENGERS FIRE PROTECTION EQUIPMENT Fire Main System § 118.310 Fire main and...

2013-10-01

45

46 CFR 118.320 - Fire hoses and nozzles.  

Code of Federal Regulations, 2013 CFR

...Shipping 4 2013-10-01 2013-10-01 false Fire hoses and nozzles. 118.320 Section 118.320...OVERNIGHT ACCOMMODATIONS FOR MORE THAN 49 PASSENGERS FIRE PROTECTION EQUIPMENT Fire Main System § 118.320 Fire hoses and...

2013-10-01

46

33 CFR 118.160 - Vertical clearance gauges.  

Code of Federal Regulations, 2010 CFR

...2010-07-01 false Vertical clearance gauges. 118.160 Section 118.160 Navigation...SIGNALS § 118.160 Vertical clearance gauges. (a) When necessary for reasons...authorize the installation of clearance gauges. Except as specified in §...

2010-07-01

47

Electrically conductive palladium-containing polyimide films  

NASA Technical Reports Server (NTRS)

Palladium addition makes light, flexible film with low resistivity to relieve space charging. Polyimide film is prepared in four steps: preparation of polyamic acid in polar solvent; addition of soluable palladium complex salt; fabrication of film of "palladium polyamic acid" solution; and thermal imidization of film to palladium-containing polyimide by 300 C heating. Lowered resistivities were achieved without loss in film flexibility or increase in film weight.

St.clair, A. K.; Furtsch, T. A.; Taylor, L. T.

1981-01-01

48

Rotational Velocity Determinations for 118 ? Scuti Variables  

NASA Astrophysics Data System (ADS)

We present a calibration method used for the determination of projected rotational velocities (vsin i) of 118 ? Scuti variables from FWHM measurements of metal lines near 4500 Å. The calibration relation used was derived from measurements of 29 stars. Of the 44 stars brighter than 8th magnitude and north of -1° declination which did not have values in the Rodríguez catalog (Rodríguez, E., López González, M. J., & López de Coca, P. 2000, A&AS, 144, 469), we present values for 38. In addition, we present new vsin i values for 10 stars south of -1° or fainter than 8th magnitude for a total of 48 vsin i values for stars with no previously published values. We acknowledge the Dominion Astrophysical Observatory for making available the 1.2-m and 1.8-m telescopes to aid in this research.

Bush, Tabitha C.; Hintz, E. G.

2009-01-01

49

Rotational Velocity Determinations for 118 ? Scuti Variables  

NASA Astrophysics Data System (ADS)

A calibration method is presented for the determination of projected rotational velocities of 118 ? Scuti variables from FWHM measurements of metal lines near 4500 Å. The calibration relation used was derived from measurements of 29 stars. Of the 44 stars brighter than 8th magnitude and north of -1° declination which did not have values in the Rodríguez catalog (Rodríguez, E., López González, M. J., & López de Coca, P. 2000, A&AS, 144, 469) we present values for 38. In addition, we present new projected rotational velocity, vsin i, values for 10 stars south of -1° or fainter than 8th magnitude for a total of 48 vsin i values for stars with no previously published values.

Bush, Tabitha C.; Hintz, Eric G.

2008-09-01

50

118-B-1 excavation treatability test procedures  

SciTech Connect

This treatability study has two purposes: to support development of the approach to be used for burial ground remediation, and to provide specific engineering information for the design of burial grounds receiving waste generated from the 100 Area removal actions. Data generated from this test will also provide performance and cost information necessary for detailed analysis of alternatives for burial ground remediation. Further details on the test requirements, milestones and data quality objectives are described in detail in the 118-B-1 Excavation Treatability Test Plan (DOE/RL-94-43). These working procedures are intended for use by field personnel to implement the requirements of the milestone. A copy of the detailed Test Plan will be kept on file at the on-site field support trailer, and will be available for review by field personnel.

Frain, J.M.

1994-08-01

51

Stable palladium alloys for diffusion of hydrogen  

NASA Technical Reports Server (NTRS)

Literature search on hydrogen absorption effect on palladium alloys revealed existence of alloy compositions in which alpha--beta transition does not take place. Survey conclusions: 40 percent gold alloy of palladium should be used in place of palladium; alloy must be free of interstitial impurities; and metallic surfaces of tube must be clean.

Patapoff, M.

1973-01-01

52

Quasitemplate synthesis of nanostructured palladium electroplates  

Microsoft Academic Search

By means of quasitemplate electrodeposition of palladium from palladium chloride solutions with additions of polyethylene glycol (PEG) and polyvinyl pyrrolidone (PVP), palladium deposits with high specific surface areas (up to 50 m2 g?1) are synthesized. The specific surface areas of the deposits tend to increase with an increase in the chain length of a polymeric additive. Some of the deposits

Galina A Tsirlina; Oleg A Petrii; Tat'yana Ya Safonova; Ivan M Papisov; Sergey Yu Vassiliev; Andrey E Gabrielov

2002-01-01

53

Palladium and Palladium-Carbon Nanotube Composite Nanomechanical Resonator  

NASA Astrophysics Data System (ADS)

For its bio-compatibility, conductivity and optical reflectivity, metallic thin films are an attractive choice to realize multifunctional micromechanical resonators. However, moderate elastic properties of metallic thin films are ill suited for high frequency applications. Meanwhile, Carbon nanotubes have shown great potential with superior electrical and mechanical properties. Combined Metal-CNT nanolaminates have increased strengths and are less susceptible to onset of mechanical nonlinearity compared to equivalent metal beams without CNT. With palladium's good affinity to CNT to further study the role of the metal-CNT interface, we realized doubly clamped beam and torsional resonators from Palladium and Palladium/CNT composite. Resonance frequencies were detected using optical modulation technique with different wavelength at room temperature under moderate vacuum. Comparing the dynamic flexural response of Pd and Pd/CNT doubly clamped beam and torsional resonators, we will also discuss the difference between Pd-CNT and Al-CNT resonators as well as actuating the resonators electrostatically and optically

Cho, Sungwan; Kim, Youngduck; Bak, Junghoon; Lee, Juhyung; Lee, Seungran; Char, Kookrin; Hong, Seunghun; Park, Yun Daniel

2009-03-01

54

Palladium/kieselguhr composition and method  

DOEpatents

A hydrogen-absorbing composition and method for making such a composition are described. The composition comprises a metal hydride, preferably palladium, deposited onto a porous substrate such as kieselguhr, for use in hydrogen-absorbing processes. The composition is made by immersing a substrate in a concentrated solution containing palladium, such as tetra-amine palladium nitrate. Palladium from the solution is deposited onto the porous substrate, which is preferably in the form of kieselguhr particles. The substrate is then removed from the solution, calcined, and heat treated. This process is repeated until the desired amount of palladium has been deposited onto the substrate.

Mosley, W.C. Jr.

1993-09-28

55

Palladium/kieselguhr composition and method  

DOEpatents

A hydrogen-absorbing composition and method for making such a composition. The composition comprises a metal hydride, preferably palladium, deposited onto a porous substrate such as kieselguhr, for use in hydrogen-absorbing processes. The composition is made by immersing a substrate in a concentrated solution containing palladium, such as tetra-amine palladium nitrate. Palladium from the solution is deposited onto the porous substrate, which is preferably in the form of kieselguhr particles. The substrate is then removed from the solution, calcined, and heat treated. This process is repeated until the desired amount of palladium has been deposited onto the substrate.

Mosley, Jr., Wilbur C. (202 Fairway Dr., New Ellenton, SC 29809)

1993-01-01

56

Anticancer drug FL118 is more than a survivin inhibitor: where is the Achilles' heel of cancer?  

PubMed Central

Can a solution be found that overcomes all chemotherapy and/or radiation resistance resulting from different genetic and epigenetic alternations in various cancer types? The answer is likely NO. However, there are two ways that may be followed to approach this goal. One way is through the use of poly-therapies that target multiple mechanisms to kill cancer cells, which is the current state of the art. This approach raises issues of high costs and/or toxic limitations, since the toxicities of each agent are often additive. This poly-pharmacy approach has not proven to be a major success, although it has proven to be superior to most current mono-pharmacy approaches. The other way to approach the goal is to find a single anticancer drug that targets multiple different treatment resistant mechanisms. In this regard, a small chemical molecule (FL118) was recently discovered by serendipity during targeted discovery of anticancer drugs using the survivin gene as a target and biomarker. FL118 was found to not only inhibit multiple antiapoptotic proteins (survivin, XIAP, cIAP2) in the inhibitor of apoptosis (IAP) family, but to also inhibit the antiapoptotic protein Mcl-1 in the Bcl-2 family, while inducing the pro-apoptotic proteins Bax and Bim expression. Importantly, inhibition of these target genes and of tumor growth by FL118 is independent of p53 status (wild type, mutant or null), although mechanisms of action may be distinct among cells with different p53 status. Therefore, FL118 may effectively control cancer that loses functional p53, in which most DNA damage drugs (if not all) show a marked lack of efficiency. Recent studies further revealed that the superior anticancer activity of FL118 is highly dependent on its primary structure and steric configuration, suggesting that FL118 may be a promising drug platform for generating novel derivatives based on its core structure. Intriguingly, although FL118 has structural similarity to irinotecan and topotecan, two FDA-approved topoisomerase 1 (Top1) inhibitors for cancer treatment, cancer cells with Top1 mutations shows little contributions of treatment resistance to FL118 antitumor activity, while strikingly increasing irinotecan and topotecan resistance. Furthermore, both irinotecan and topotecan are the efflux pump ABCG2 substrates; cancer cells with high expression of ABCG2 showed strong irinotecan and topotecan resistance. In contrast, FL118 is not an ABCG2 substrate; ABCG2 overexpression in cancer cells does not show resistance to FL118 treatment. Current evidence suggests that future studies may unravel more unexpected mechanisms of action for this unique small molecule FL118.

Li, Fengzhi

2014-01-01

57

Palladium-mediated intracellular chemistry  

Microsoft Academic Search

Many important intracellular biochemical reactions are modulated by transition metals, typically in the form of metalloproteins. The ability to carry out selective transformations inside a cell would allow researchers to manipulate or interrogate innumerable biological processes. Here, we show that palladium nanoparticles trapped within polystyrene microspheres can enter cells and mediate a variety of Pd0-catalysed reactions, such as allylcarbamate cleavage

Rahimi M. Yusop; Asier Unciti-Broceta; Emma M. V. Johansson; Rosario M. Sánchez-Martín; Mark Bradley

2011-01-01

58

Study of Palladium Plating Components.  

National Technical Information Service (NTIS)

Palladium deposits were prepared by electrolysis for evaluation as catalytic materials. Electrolysis was carried out in acidic solutions consisting of either 1.0 M in NaCl and 0.01 M PdCl2 or 1.0 M NaCl and 0.04 M PdCl2. It was during the preparation of t...

1977-01-01

59

Palladium Catalyzed Reduction of Nitrobenzene.  

ERIC Educational Resources Information Center

Compares two palladium (Pd/C) reducing systems to iron/tin-hydrochloric acid (Fe/HCl and Sn/HCl) reductions and suggests an efficient, clean, and inexpensive procedures for the conversion of nitrobenzene to aniline. Includes laboratory procedures used and discussion of typical results obtained. (JN)

Mangravite, John A.

1983-01-01

60

40 CFR 51.118 - Stack height provisions.  

Code of Federal Regulations, 2013 CFR

...2013-07-01 2013-07-01 false Stack height provisions. 51.118 Section 51... Control Strategy § 51.118 Stack height provisions. (a) The plan must...affected by so much of any source's stack height that exceeds good engineering...

2013-07-01

61

46 CFR 118.500 - Required number, type, and location.  

Code of Federal Regulations, 2013 CFR

...Required number, type, and location. 118.500 Section 118...Required number, type, and location. (a) Each portable...Medium Min. size Operating station 1 B-I, C-I Halon...sprinkler system and exposed to weather must have one B-II...

2013-10-01

62

The ITEA-NASA STS-118 Design Challenges  

ERIC Educational Resources Information Center

In conjunction with the August 8, 2007 launch of STS-118, the International Technology Education Association (ITEA) and National Aeronautics and Space Administration (NASA) developed and recently debuted curricular units for Grades K-12 on Space Exploration, known as STS-118 Design Challenges. The units focus on aspects of the themes that NASA…

Meade, Shelli D.; Caron, Daniel W.; Gray, Aaron; Weaver, Kim

2008-01-01

63

Electrically conductive palladium containing polyimide films  

NASA Technical Reports Server (NTRS)

Lightweight, high temperature resistant, electrically conductive, palladium containing polyimide films and methods for their preparation are described. A palladium (II) ion-containing polyamic acid solution is prepared by reacting an aromatic dianhydride with an equimolar quantity of a palladium II ion-containing salt or complex and the reactant product is cast as a thin film onto a surface and cured at approximately 300 C to produce a flexible electrically conductive cyclic palladium containing polyimide. The source of palladium ions is selected from the group of palladium II compounds consisting of LiPdCl4, PdS(CH3)2Cl2Na2PdCl4, and PdCl2. The films have application to aerodynamic and space structures and in particular to the relieving of space charging effects.

Taylor, L. T.; St.clair, A. K.; Carver, V. C.; Furtsch, T. A. (inventors)

1982-01-01

64

Palladium as electrode in DNA sequencing  

NASA Astrophysics Data System (ADS)

We construct a molecular junction comprising two identical ``reader'' molecules that are each linked on one end to a DNA single base via hydrogen bonds and on the other end to a palladium electrode. The structure of the junction is thus palladium-reader-base-reader-palladium. The palladium-reader contacts occur via Pd-S bonds. We calculated the electronic structure and conductance of the molecular junctions. Compared with the performance of molecular junctions with gold or titanium nitride electrodes, the current-voltage characteristics of the molecular junctions with palladium electrodes show higher sensitivity to the identity of the bridging DNA base, allowing the DNA bases to be distinguished more easily. Therefore, palladium is a superior electrode for molecular electronics and DNA sequencing.

Chen, Xiang

2013-08-01

65

LLE Review 118 (January-March 2009)  

SciTech Connect

This issue has the following articles: (1) Applied Plasma Spectroscopy: Laser-Fusion Experiments; (2) Relativistic Electron-Beam Transport Studies Using High-Resolution, Coherent Transition Radiation Imaging; (3) Pressure-Driven, Resistive Magnetohydrodynamic Interchange Instabilities in Laser-Produced, High-Energy-Density Plasmas; (4) Extended Model for Polymer Cholesteric Liquid Crystal Flake Reorientation and Relaxation; (5) Modeling the Effects of Microencapsulation on the Electro-Optic Behavior of Polymer Cholesteric Liquid Crystal Flakes; (6) Capillarity and Dielectrophoresis of Liquid Deuterium; and (7) A Stable Mid-IR, GaSb-Based Diode Laser Source for Cryogenic Target Layering at the OMEGA Laser Facility.

Bittle, W., editor

2009-08-03

66

Palladium and platinum famotidine complexes  

Microsoft Academic Search

The molecule of the well-known ulceration inhibitor, famotidine, is an excellent coordinator of transition metal ions. The guanidine, amine group and thiazole nitrogen, and the thioether sulphur are preferential sites to bind metal ions. Pd(II) and Pt(II) derivatives of famotidine have been synthesized and studied structurally. There is evidence that the palladium complex is a monomer while the platinum complex

G. B Onoa; V Moreno

1998-01-01

67

16 CFR 23.7 - Misuse of the words “platinum,” “iridium,” “palladium,” “ruthenium,” “rhodium,” and “osmium.”  

Code of Federal Regulations, 2011 CFR

...platinum,” “iridium,” “palladium,” “ruthenium,” “rhodium,” and...platinum,” “iridium,” “palladium,” “ruthenium,” “rhodium...Metals (PGM) are Platinum, Iridium, Palladium, Ruthenium, Rhodium, and...

2011-01-01

68

16 CFR 23.7 - Misuse of the words “platinum,” “iridium,” “palladium,” “ruthenium,” “rhodium,” and “osmium.”  

Code of Federal Regulations, 2012 CFR

...platinum,” “iridium,” “palladium,” “ruthenium,” “rhodium,” and...platinum,” “iridium,” “palladium,” “ruthenium,” “rhodium...Metals (PGM) are Platinum, Iridium, Palladium, Ruthenium, Rhodium, and...

2012-01-01

69

24 CFR 943.118 - What is a consortium?  

Code of Federal Regulations, 2010 CFR

...SECRETARY FOR PUBLIC AND INDIAN HOUSING, DEPARTMENT OF HOUSING AND URBAN DEVELOPMENT PUBLIC HOUSING AGENCY CONSORTIA AND JOINT VENTURES Consortia § 943.118 What is a consortium? A consortium consists of two or more PHAs that join...

2010-04-01

70

118. Guillotine type gate (in open position) to regulate stove ...  

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

118. Guillotine type gate (in open position) to regulate stove exhausts to underground flue. - Sloss-Sheffield Steel & Iron, First Avenue North Viaduct at Thirty-second Street, Birmingham, Jefferson County, AL

71

118. Photographic copy of historic photo, April 5, 1932 (original ...  

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

118. Photographic copy of historic photo, April 5, 1932 (original print filed in Record Group 115, National Archives, Washington, D.C.). INVAR VOLUME METER, PANEL NO. 3, OWYHEE DAM. - Owyhee Dam, Across Owyhee River, Nyssa, Malheur County, OR

72

46 CFR 171.118 - Automatic ventilators and side ports.  

Code of Federal Regulations, 2013 CFR

...STABILITY SPECIAL RULES PERTAINING TO VESSELS CARRYING PASSENGERS Openings in the Side of a Vessel Below the Bulkhead or Weather Deck § 171.118 Automatic ventilators and side ports. (a) An automatic ventilator must not be fitted in the...

2013-10-01

73

29 CFR 570.118 - Sixteen-year minimum.  

Code of Federal Regulations, 2013 CFR

...DEPARTMENT OF LABOR REGULATIONS CHILD LABOR REGULATIONS, ORDERS AND STATEMENTS...Statements of Interpretation of the Child Labor Provisions of the Fair Labor Standards...1938, as Amended Oppressive Child Labor § 570.118...

2013-07-01

74

118. Historic American Buildings Survey, Donald W. Dickensheets, Photographer. April ...  

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

118. Historic American Buildings Survey, Donald W. Dickensheets, Photographer. April 29, 1940. EAST TRANSEPT MURAL, 'CHILDHOOD OF VIRGIN MARY'. (NORTH ELEVATION) - San Xavier del Bac Mission, Mission Road, Tucson, Pima County, AZ

75

Mali Biodiversity and Tropical Forests 118/119 Assessment.  

National Technical Information Service (NTIS)

The purpose of this Mali 118/119 Biodiversity and Tropical Forest Assessment is to synthesize information on the institutional and legislative structures in Mali that relate to biodiversity, report on the state of biodiversity resources in Mali, identify ...

2008-01-01

76

Biaxially textured metal substrate with palladium layer  

DOEpatents

Described is an article comprising a biaxially textured metal substrate and a layer of palladium deposited on at least one major surface of the metal substrate; wherein the palladium layer has desired in-plane and out-of-plane crystallographic orientations, which allow subsequent layers that are applied on the article to also have the desired orientations.

Robbins, William B [Maplewood, MN

2002-12-31

77

Platinum and palladium in roadside dust  

Microsoft Academic Search

Automobile catalytic converters apparently release significant quantities of platinum and palladium to the roadside environment. Dust samples collected from broad-leaved plants contained as high as 0.7 ppm of platinum and 2.5 times less palladium. Rains may wash this concentrate into local water systems or the ocean. 8 references, 1 table.

Vernon F. Hodge; Martha O. Stallard

1986-01-01

78

Target  

US Patent & Trademark Office Database

The present invention relates to an isolated target sequence. The target sequence is a splice variant of PDE5 called a PDE5a1, a component of which is presented as SEQ ID No 1. The identified target sequence of the present invention may be used to as a target to identify agents (such as modulators) useful in the prevention and/or treatment of a disease associated with scarring and/or fibrosis or to selectively identify smooth muscle cells and myofibroblasts and myoepithelial cells in samples of normal and diseased tissue from individuals.

2004-09-21

79

Biochemical Analysis of the Role of G118R-Linked Dolutegravir Drug Resistance Substitutions in HIV-1 Integrase  

PubMed Central

Drug resistance mutations (DRMs) have been reported for all currently approved anti-HIV drugs, including the latest integrase strand transfer inhibitors (INSTIs). We previously used the new INSTI dolutegravir (DTG) to select a G118R integrase resistance substitution in tissue culture and also showed that secondary substitutions emerged at positions H51Y and E138K. Now, we have characterized the impact of the G118R substitution, alone or in combination with either H51Y or E138K, on 3? processing and integrase strand transfer activity. The results show that G118R primarily impacted the strand transfer step of integration by diminishing the ability of integrase-long terminal repeat (LTR) complexes to bind target DNA. The addition of H51Y and E138K to G118R partially restored strand transfer activity by modulating the formation of integrase-LTR complexes through increasing LTR DNA affinity and total DNA binding, respectively. This unique mechanism, in which one function of HIV integrase partially compensates for the defect in another function, has not been previously reported. The G118R substitution resulted in low-level resistance to DTG, raltegravir (RAL), and elvitegravir (EVG). The addition of either of H51Y or E138K to G118R did not enhance resistance to DTG, RAL, or EVG. Homology modeling provided insight into the mechanism of resistance conferred by G118R as well as the effects of H51Y or E138K on enzyme activity. The G118R substitution therefore represents a potential avenue for resistance to DTG, similar to that previously described for the R263K substitution. For both pathways, secondary substitutions can lead to either diminished integrase activity and/or increased INSTI susceptibility.

Quashie, Peter K.; Mesplede, Thibault; Han, Ying-Shan; Veres, Tamar; Osman, Nathan; Hassounah, Said; Sloan, Richard D.; Xu, Hong-Tao

2013-01-01

80

38 CFR 16.118 - Applications and proposals lacking definite plans for involvement of human subjects.  

Code of Federal Regulations, 2013 CFR

...lacking definite plans for involvement of human subjects. 16.118 Section 16.118...DEPARTMENT OF VETERANS AFFAIRS PROTECTION OF HUMAN SUBJECTS § 16.118 Applications and...lacking definite plans for involvement of human subjects. Certain types...

2013-07-01

81

28 CFR 46.118 - Applications and proposals lacking definite plans for involvement of human subjects.  

Code of Federal Regulations, 2013 CFR

...lacking definite plans for involvement of human subjects. 46.118 Section 46.118...OF JUSTICE (CONTINUED) PROTECTION OF HUMAN SUBJECTS § 46.118 Applications...lacking definite plans for involvement of human subjects. Certain types...

2013-07-01

82

49 CFR 11.118 - Applications and proposals lacking definite plans for involvement of human subjects.  

Code of Federal Regulations, 2013 CFR

...lacking definite plans for involvement of human subjects. 11.118 Section 11.118...Secretary of Transportation PROTECTION OF HUMAN SUBJECTS § 11.118 Applications...lacking definite plans for involvement of human subjects. Certain types...

2013-10-01

83

41 CFR 102-118.50 - How does my agency pay for transportation services?  

Code of Federal Regulations, 2013 CFR

...2013-07-01 false How does my agency pay for transportation services? 102-118.50 Section 102-118...Continued) FEDERAL MANAGEMENT REGULATION TRANSPORTATION 118-TRANSPORTATION PAYMENT AND AUDIT Ordering and Paying...

2013-07-01

84

Microstructure and Segregation Behavior of Palladium in Silver-Copper-Palladium Alloys  

Microsoft Academic Search

It has been reported that the addition of palladium can modify the microstructure and improve the properties of Ag-Cu eutectic alloy as well as admixed Cu-rich amalgam. The purpose of this work was to study the microstructure and segregation behavior of palladium in a series of Ag-Cu-Pd alloys. All microstructural and microchemical results consistently indicated a strong tendency for palladium

K. I. Chen; J. H. Chern Lin; C. P. Ju

1996-01-01

85

A Novel Small Molecule FL118 That Selectively Inhibits Survivin, Mcl-1, XIAP and cIAP2 in a p53-Independent Manner, Shows Superior Antitumor Activity  

PubMed Central

Drug/radiation resistance to treatment and tumor relapse are major obstacles in identifying a cure for cancer. Development of novel agents that address these challenges would therefore be of the upmost importance in the fight against cancer. In this regard, studies show that the antiapoptotic protein survivin is a central molecule involved in both hurdles. Using cancer cell-based survivin-reporter systems (US 7,569,221 B2) via high throughput screening (HTS) of compound libraries, followed by in vitro and in vivo analyses of HTS-derived hit-lead compounds, we identified a novel anticancer compound (designated FL118). FL118 shows structural similarity to irinotecan. However, while the inhibition of DNA topoisomerase 1 activity by FL118 was no better than the active form of irinotecan, SN-38 at 1 µM, FL118 effectively inhibited cancer cell growth at less than nM levels in a p53 status-independent manner. Moreover, FL118 selectively inhibited survivin promoter activity and gene expression also in a p53 status-independent manner. Although the survivin promoter-reporter system was used for the identification of FL118, our studies revealed that FL118 not only inhibits survivin expression but also selectively and independently inhibits three additional cancer-associated survival genes (Mcl-1, XIAP and cIAP2) in a p53 status-independent manner, while showing no inhibitory effects on control genes. Genetic silencing or overexpression of FL118 targets demonstrated a role for these targets in FL118’s effects. Follow-up in vivo studies revealed that FL118 exhibits superior antitumor efficacy in human tumor xenograft models in comparison with irinotecan, topotecan, doxorubicin, 5-FU, gemcitabine, docetaxel, oxaliplatin, cytoxan and cisplatin, and a majority of mice treated with FL118 showed tumor regression with a weekly × 4 schedule. FL118 induced favorable body-weight-loss profiles (temporary and reversible) and was able to eliminate large tumors. Together, the molecular targeting features of FL118 plus its superior antitumor activity warrant its further development toward clinical trials.

Cheng, Qiuying; Keefe, James T.; Rustum, Youcef M.; Li, Fengzhi

2012-01-01

86

Generation of palladium blacks from organometallic compounds  

SciTech Connect

The authors used chemical analysis, derivatography, and IR and x-ray photoelectron spectroscopy to study blacks prepared from palladium organometallic compounds. The active phase on the surface of these blacks is palladium in an oxidation state close to zero. The activity and selectivity of these catalysts in the liquid-phase hydrogenation of acetylenic bonds depends on the nature of the ligands of the starting pi-allylic palladium compounds, increasing in the series Cl is less than C/sub 5/H/sub 5/ is less than PPh/sub 3/.

Fasman, A.B.; Perkas, N.V.; Vozdvizhenskii, V.F.

1985-12-01

87

Compaction Studies of Palladium/Aluminum Powders.  

National Technical Information Service (NTIS)

A compaction study has been performed comparing predicted and experimentally determined density gradients in palladium/aluminum mixtures of differing weight fractions. A modified constitutive equation for porous media was used to predict the density gradi...

O. L. Burchett M. R. Birnbaum C. T. Oien

1978-01-01

88

Multiple Additions of Palladium to C60  

Microsoft Academic Search

Density functional theory calculations on exohedral metallofullerenes PdnC60 show that the palladium–fullerene bond energy remains essentially constant for n=1?6. A novel Pd2(??C60) structure with the two metal atoms bridging over a six?membered ring has been identified as the most stable arrangement of two palladium atoms on the surface of C60, although entropy considerations suggest that both isolated atoms and weakly

Oleksandr Loboda; Vidar R. Jensen; Knut J. Børve

2006-01-01

89

40 CFR 92.118 - Analyzer checks and calibrations.  

Code of Federal Regulations, 2013 CFR

...AGENCY (CONTINUED) AIR PROGRAMS (CONTINUED) CONTROL OF AIR POLLUTION FROM LOCOMOTIVES...Procedures § 92.118 Analyzer checks and calibrations...valve and observing the analyzer response on a chart recorder...would select a âroom airâ sample and the...

2013-07-01

90

118. #3 SHAFT ALLEY (PROPELLER SHAFT) FORWARD LOOKING AFT ...  

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

118. #3 SHAFT ALLEY (PROPELLER SHAFT) - FORWARD LOOKING AFT ON PORT SIDE SHOWING THE SHAFT, SHAFT PACKING GLAND, SHAFT SEAL COOLING WATER LINE AND FIVE INCH FIRE MAIN PIPING. - U.S.S. HORNET, Puget Sound Naval Shipyard, Sinclair Inlet, Bremerton, Kitsap County, WA

91

19 CFR 12.118 - Toxic Substances Control Act.  

Code of Federal Regulations, 2013 CFR

...Chemical Substances in Bulk and As Part of Mixtures and Articles § 12.118 Toxic Substances...chemical substance in bulk or as part of a mixture, or article containing a chemical substance or mixture, is governed by the Toxic Substances...

2013-04-01

92

118. COTTONWOOD CREEK SPILL, TWIN FALLS COUNTY, SOUTH OF KIMBERLY, ...  

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

118. COTTONWOOD CREEK SPILL, TWIN FALLS COUNTY, SOUTH OF KIMBERLY, IDAHO; WEST VIEW OF GATES ON HIGH LINE CANAL. - Milner Dam & Main Canal: Twin Falls Canal Company, On Snake River, 11 miles West of city of Burley, Idaho, Twin Falls, Twin Falls County, ID

93

CNN Newsroom Classroom Guides. December 1-18, 1998.  

ERIC Educational Resources Information Center

These guides, designed to accompany the daily Cable News Network (CNN) Newsroom broadcasts for December 1-18, 1998, provide program rundowns, suggestions for class activities and discussion, links to relevant World Wide Web sites, and a list of related news terms. Top stories include: World AIDS Day/AIDS history, Exxon and Mobile announce a…

Cable News Network, Atlanta, GA.

94

Direct synthesis of palladium porphyrins from acyldipyrromethanes.  

PubMed

[reaction: see text] Palladium porphyrins are valuable photosensitizers and luminescent agents in biology and materials chemistry. New methodology is described wherein a 1-acyldipyrromethane is converted into the palladium chelate of a trans-A(2)B(2) porphyrin via a one-flask reaction. The reaction entails self-condensation of the 1-acyldipyrromethane in refluxing ethanol containing KOH (5-10 mol equiv) and Pd(CH(3)CN)(2)Cl(2) (0.6 mol equiv) exposed to air. This direct route to palladium porphyrins is more expedient than the four steps of the traditional synthesis: (1) reduction of the 1-acyldipyrromethane; (2) acid-catalyzed condensation; (3) oxidation of the porphyrinogen intermediate; and (4) metal insertion. The new synthesis requires neither acid nor DDQ and formally entails only a 2e(-) + 2H(+) oxidation overall versus the traditional multistep synthesis which requires a 2e(-) + 2H(+) reduction per each 1-acyldipyrromethane (4e(-) + 4H(+) overall) followed by a 6e(-) + 6H(+) oxidation. The analogous reaction of a 1,9-diacyldipyrromethane and a dipyrromethane also gives the palladium porphyrin. Seven palladium porphyrins have been prepared in yields of 25-57%. The direct route also can be used with Cu(OAc)(2).H(2)O to give the copper porphyrin albeit in low yield. In summary, this methodology readily affords palladium porphyrins directly from acyldipyrromethanes. PMID:15844983

Sharada, Duddu S; Muresan, Ana Z; Muthukumaran, Kannan; Lindsey, Jonathan S

2005-04-29

95

Palladium and platinum famotidine complexes.  

PubMed

The molecule of the well-known ulceration inhibitor, famotidine, is an excellent coordinator of transition metal ions. The guanidine, amine group and thiazole nitrogen, and the thioether sulphur are preferential sites to bind metal ions. Pd(II) and Pt(II) derivatives of famotidine have been synthesized and studied structurally. There is evidence that the palladium complex is a monomer while the platinum complex forms a dimer. Due to the interesting structure of the platinum complex several assays have examined the possible antitumour activity. Changes in DNA conformation induced by both complexes have been detected by CD, interstrand crosslinking interactions and electrophoretic mobility, but studies of the cytotoxicity of the platinum compound with U937 human leukemia cells and HeLA human womb carcinoma cells show only a small antiproliferative potential. PMID:10065533

Onoa, G B; Moreno, V

1998-12-01

96

Palladium Catalysis for Energy Applications  

SciTech Connect

Palladium (Pd) is an attractive catalyst for a range of new combustion applications comprising primary new technologies for future industrial energy needs, including gas turbine catalytic combustion, auto exhaust catalysts, heating and fuel cells. Pd poses particular challenges because it changes both chemical state and morphology as a function of temperature and reactant environment and those changes result in positive and negative changes in activity. Interactions with the support, additives, water, and contaminants as well as carbon formation have also been observed to affect Pd catalyst performance. This report describes the results of a 3.5 year project that resolves some of the conflicting reports in the literature about the performance of Pd-based catalysts.

Pfefferle, L. D.; Datye, A.

2001-03-01

97

Effect of Palladium Form on Tetraphenylborate Decomposition Rate.  

National Technical Information Service (NTIS)

Palladium catalyzes the decomposition of tetraphenylborate in alkaline solutions. Researchers postulate several decomposition mechanisms that differ in the form of the palladium catalyst. Potential forms include solid and soluble, different soluble specie...

D. D. Walker

1998-01-01

98

Palladium catalyzed hydrogenation of bio-oils and organic compounds  

DOEpatents

The invention provides palladium-catalyzed hydrogenations of bio-oils and certain organic compounds. Experimental results have shown unexpected and superior results for palladium-catalyzed hydrogenations of organic compounds typically found in bio-oils.

Elliott, Douglas C [Kennewick, WA; Hu, Jianli [Richland, WA; Hart,; Todd, R [Kennewick, WA; Neuenschwander, Gary G [Burbank, WA

2011-06-07

99

Calorimetric study on interaction of dioxygen with alumina supported palladium  

Microsoft Academic Search

Pd\\/Al2O3 samples of various palladium loadings were prepared with the incipient-wetness method. With an increase in the palladium loading, the average diameter (d) of palladium crystallites on these samples was estimated from chemisorption of hydrogen to vary from 10 to 80 Å. Also, the phenomena of oxidizing these dispersed palladium crystallites with dioxygen were studied by a simultaneous TG-DSC instrument.

Yung-Shen Ho; Chen-Bin Wang; Chuin-Tih Yeh

1996-01-01

100

Preparation and characterization of a composite palladium-ceramic membrane  

Microsoft Academic Search

Composite palladium--ceramic membranes with palladium films ranging from 11.4 to 20 [mu]m were made by depositing palladium on the inside surface of asymmetric tubular ceramic membranes. Electroless plating was used to deposit the palladium film. Membranes were characterized by conducting permeability experiments with hydrogen, nitrogen, and helium at temperatures from 723 to 913 K and feed pressures from 160 to

John P. Collins

1993-01-01

101

ENCAPSULATION OF PALLADIUM IN POROUS WALL HOLLOW GLASS MICROSPHERES  

SciTech Connect

A new encapsulation method was investigated in an attempt to develop an improved palladium packing material for hydrogen isotope separation. Porous wall hollow glass microspheres (PWHGMs) were produced by using a flame former, heat treating and acid leaching. The PWHGMs were then filled with palladium salt using a soak-and-dry process. The palladium salt was reduced at high temperature to leave palladium inside the microspheres.

Heung, L; George Wicks, G; Ray Schumacher, R

2008-04-09

102

Oxidation of methane over palladium catalysts: effect of the support  

Microsoft Academic Search

This work is focused on the deep catalytic oxidation of methane over supported palladium catalysts. The influences of the metal loading, oxidation state of palladium, nature of supports, presence of promoters in the supports (for zirconia-based supports), and thermal stability have been studied experimentally. Catalysts were prepared by incipient wetness of commercially available supports with aqueous solutions of palladium nitrate.For

Lara S. Escandón; Salvador Ordóñez; Aurelio Vega; Fernando V. D??ez

2005-01-01

103

Effect of Fretting on the Contact Resistance of Palladium  

Microsoft Academic Search

The fretting of palladium contacts was studied at conditions relevant to their use in separable electronic connectors. Wrought, clad, and electroplated palladium mated to wrought palladium develop high contact resistance due to the formation of friction polymer. This can occur in ordinary room air which contains traces of organic air pollutants. Contact resistance changes diminish as force is increased. Static

MORTON ANTLER; EDWARD S. SPROLES

1982-01-01

104

Cleanup Verification Package for the118-F-2 Burial Ground  

SciTech Connect

This cleanup verification package documents completion of remedial action, sampling activities, and compliance with cleanup criteria for the 118-F-2 Burial Ground. This burial ground, formerly called Solid Waste Burial Ground No. 1, was the original solid waste disposal site for the 100-F Area. Eight trenches contained miscellaneous solid waste from the 105-F Reactor and one trench contained solid waste from the biology facilities.

J. M. Capron and K. A. Anselm

2008-02-21

105

118. Photographic copy of drawing (undated, original drawing in Archives, ...  

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

118. Photographic copy of drawing (undated, original drawing in Archives, Office of the Building, Administration Building, Sears, Roebuck and Company Mail Order Plant, Chicago, Illinois). Larsen-Wulff Architects. 1/16 inch to one foot. Drawing of the entire floor plan from Homan Avenue to Central Park Avenue, probably traced in the 1970's or early 1980's. FOURTH FLOOR PLAN - WEST HALF - Sears Roebuck & Company Mail Order Plant, Merchandise Building, 924 South Homan Avenue, Chicago, Cook County, IL

106

Palladium Implanted Silicon Carbide for Hydrogen Sensing  

NASA Technical Reports Server (NTRS)

Silicon carbide is intended for use in fabrication of high-temperature, efficient hydrogen sensors. Traditionally, when a palladium coating is applied on the exposed surface of SiC, the chemical reaction between palladium and hydrogen produces a detectable change in the surface chemical potential. We have produced both a palladium coated SiC as well as a palladium, ion implanted SiC sensor. The palladium implantation was done at 500 C into the Si face of 6H, N-type SiC at various energies, and at various fluences. Then, we measured the hydrogen sensitivity response of each fabricated sensor by exposing them to hydrogen while monitoring the current flow across the p-n junction(s), with respect to time. The sensitivity of each sensor was measured at temperatures between 27 and 300 C. The response of the SiC sensors produced by Pd implantation has revealed a completely different behaviour than the SiC sensors produced by Pd deposition. In the Pd-deposited SiC sensors as well as in the ones reported in the literature, the current rises in the presence of hydrogen at room temperature as well as at elevated temperatures. In the case of Pd-implanted SiC sensors, the current decreases in the presence of hydrogen whenever the temperature is raised above 100 C. We will present the details and conclusions from the results obtained during this meeting.

Muntele, C. I.; Ila, D.; Zimmerman, R. L.; Muntele, L.; Poker, D. B.; Hensley, D. K.; Larkin, David (Technical Monitor)

2001-01-01

107

Electrical transport characteristics of DNA wrapped carbon nanotubes contacted to palladium and palladium oxide electrodes.  

SciTech Connect

DNA-wrapped carbon nanotubes (DNA-CNT) have generated attention due the ability to disperse cleanly into solution, and by the possibility of sorting nanotubes according to size and conductivity. In order to learn more about the effects of DNA on the electrical transport characteristics of single wall carbon nanotubes, we fabricate and test a series of devices consisting of DNA-wrapped CNTs placed across gold, palladium, and palladium oxide electrodes. In addition, we look at how DNA functionalized CNTs react to presence of hydrogen, which has previously been shown to affect the conductivity of CNTs when in contact with palladium.

Dentinger, Paul M.; Leonard, Francois; Jones, Frank Eugene; Talin, Albert Alec

2005-03-01

108

Unexpected bond activations promoted by palladium nanoparticles.  

PubMed

Thioether-phosphines, 1 and 2, were applied for the stabilisation of palladium nanoparticles (PdNPs) synthesised by a bottom-up methodology, using [Pd2(dba)3] as an organometallic precursor. For the phenyl containing ligand 1, small (d(mean) = 1.6 nm), well-defined and dispersed nanoparticles were obtained; however, ligand 2 involving a long alkyl chain led to agglomerates. NMR and GC-MS analyses throughout the synthesis of the nanomaterials revealed partial cleavage of ligands by C-S and C-P bond activations, and XPS spectra of the isolated nanoparticles indicated the presence of both thioether-phosphines and their fragments on the metallic surface. Reactivity studies of molecular palladium systems as well as on extended palladium surfaces pointed out that cluster entities are responsible for C-heteroatom activations, triggering structure modifications of stabilisers during the synthesis of PdNPs. PMID:24754040

López-Vinasco, A M; Favier, I; Pradel, C; Huerta, L; Guerrero-Ríos, I; Teuma, E; Gómez, M; Martin, E

2014-06-28

109

Reactions of hydroxymatairesinol over supported palladium catalysts  

Microsoft Academic Search

In this work, hydroxymatairesinol (extracted from Norway spruce knots) was hydrogenolyzed to matairesinol over palladium impregnated H-Beta-300, H-Beta-150, H-Beta-25, H-Beta-11, H-Y, H-Mordenite, H-MCM-41, H-ZSM-5, SiO2, and Al2O3. H-Beta-25 without palladium was also investigated. The hydrogenolysis was performed in 2-propanol at 70?°C under hydrogen and nitrogen atmospheres in a stirred glass reactor. The catalysts were characterized by nitrogen physisorption, direct current

Heidi Markus; Päivi Mäki-Arvela; Narendra Kumar; Teemu Heikkilä; Vesa-Pekka Lehto; Rainer Sjöholm; Bjarne Holmbom; Tapio Salmi; Dmitry Yu. Murzin

2006-01-01

110

Highly Concentrated Palladium Hydrides/Deuterides; Theory  

SciTech Connect

Accomplishments are reported in these areas: tight-binding molecular dynamics study of palladium; First-principles calculations and tight-binding molecular dynamics simulations of the palladium-hydrogen system; tight-binding studies of bulk properties and hydrogen vacancies in KBH{sub 4}; tight-binding study of boron structures; development of angular dependent potentials for Pd-H; and density functional and tight-binding calculations for the light-hydrides NaAlH4 and NaBH4

Papaconstantopoulos, Dimitrios

2013-11-26

111

Thermodynamic stability of palladium alloys: Part I: The palladium-niobium system  

NASA Astrophysics Data System (ADS)

The palladium activities of 12 palladium-niobium alloys (compositions from 60Pd40Nb to 97Pd3Nb) have been determined experimentally with a twin-chamber Knudsen cell mass spectrometer between 1450 and 1750 K. From the measured aPd data, other relevant thermo-dynamic properties are calculated. The ?Gf o and ?Hf o of Pd-Nb alloys thus obtained are com-pared with the published values estimated on the basis of empirical models. The results of the present work show a strong attractive interaction in the solid state between the palladium atoms and the niobium atoms. The measured palladium activities show a strong negative deviation from the ideal solution behavior.

Stickney, M. J.; Chandrasekharaiah, M. S.; Gingerich, K. A.; Speed, J. A.

1991-09-01

112

46 CFR 118.420 - Pre-engineered fixed gas fire extinguishing systems.  

Code of Federal Regulations, 2013 CFR

...2013-10-01 false Pre-engineered fixed gas fire extinguishing systems. 118...PASSENGERS FIRE PROTECTION EQUIPMENT Fixed Fire Extinguishing and Detecting Systems § 118.420 Pre-engineered fixed gas fire extinguishing systems....

2013-10-01

113

41 CFR 102-118.410 - Can GSA suspend my agency's prepayment audit program?  

Code of Federal Regulations, 2010 CFR

...suspend my agency's prepayment audit program? 102-118.410 Section...Suspension of Agency Prepayment Audit Programs § 102-118.410 Can GSA suspend my agency's prepayment audit program? (a) Yes, the Director...

2010-07-01

114

41 CFR 102-118.410 - Can GSA suspend my agency's prepayment audit program?  

Code of Federal Regulations, 2010 CFR

...suspend my agency's prepayment audit program? 102-118.410 Section...Suspension of Agency Prepayment Audit Programs § 102-118.410 Can GSA suspend my agency's prepayment audit program? (a) Yes, the Director...

2009-07-01

115

22 CFR 225.118 - Applications and proposals lacking definite plans for involvement of human subjects.  

Code of Federal Regulations, 2013 CFR

...definite plans for involvement of human subjects. 225.118 Section...Relations AGENCY FOR INTERNATIONAL DEVELOPMENT PROTECTION OF HUMAN SUBJECTS § 225.118 Applications...definite plans for involvement of human subjects....

2013-04-01

116

45 CFR 690.118 - Applications and proposals lacking definite plans for involvement of human subjects.  

Code of Federal Regulations, 2013 CFR

...lacking definite plans for involvement of human subjects. 690.118 Section 690...NATIONAL SCIENCE FOUNDATION PROTECTION OF HUMAN SUBJECTS § 690.118 Applications...lacking definite plans for involvement of human subjects. Certain types...

2013-10-01

117

32 CFR 219.118 - Applications and proposals lacking definite plans for involvement of human subjects.  

Code of Federal Regulations, 2013 CFR

...lacking definite plans for involvement of human subjects. 219.118 Section 219...CONTINUED) MISCELLANEOUS PROTECTION OF HUMAN SUBJECTS § 219.118 Applications...lacking definite plans for involvement of human subjects. Certain types...

2013-07-01

118

45 CFR 46.118 - Applications and proposals lacking definite plans for involvement of human subjects.  

Code of Federal Regulations, 2013 CFR

...proposals lacking definite plans for involvement of human subjects. 46.118 Section 46.118 Public Welfare DEPARTMENT OF HEALTH AND HUMAN SERVICES GENERAL ADMINISTRATION PROTECTION OF HUMAN SUBJECTS Basic HHS Policy for...

2013-10-01

119

34 CFR 97.118 - Applications and proposals lacking definite plans for involvement of human subjects.  

Code of Federal Regulations, 2013 CFR

...proposals lacking definite plans for involvement of human subjects. 97.118 Section 97.118...Secretary, Department of Education PROTECTION OF HUMAN SUBJECTS Federal Policy for the Protection of Human Subjects (Basic ED Policy for...

2013-07-01

120

40 CFR 26.118 - Applications and proposals lacking definite plans for involvement of human subjects.  

Code of Federal Regulations, 2013 CFR

...lacking definite plans for involvement of human subjects. 26.118 Section 26.118...PROTECTION AGENCY GENERAL PROTECTION OF HUMAN SUBJECTS Basic EPA Policy for Protection of Subjects in Human Research Conducted or Supported by EPA...

2013-07-01

121

37 CFR 1.18 - Patent post allowance (including issue) fees.  

Code of Federal Regulations, 2013 CFR

37 Patents, Trademarks, and Copyrights 1 2013-07-01 2013-07-01 false Patent post allowance (including issue) fees. 1.18 Section 1.18 Patents, Trademarks, and Copyrights UNITED STATES PATENT AND TRADEMARK...

2013-07-01

122

45 CFR 690.118 - Applications and proposals lacking definite plans for involvement of human subjects.  

Code of Federal Regulations, 2010 CFR

...definite plans for involvement of human subjects. 690.118 Section...Welfare (Continued) NATIONAL SCIENCE FOUNDATION PROTECTION OF HUMAN SUBJECTS § 690.118 Applications...definite plans for involvement of human subjects....

2009-10-01

123

45 CFR 690.118 - Applications and proposals lacking definite plans for involvement of human subjects.  

Code of Federal Regulations, 2010 CFR

...definite plans for involvement of human subjects. 690.118 Section...Welfare (Continued) NATIONAL SCIENCE FOUNDATION PROTECTION OF HUMAN SUBJECTS § 690.118 Applications...definite plans for involvement of human subjects....

2010-10-01

124

12 CFR 221.118 - Bank arranging for extension of credit by corporation.  

...false Bank arranging for extension of credit by corporation. 221.118 Section...FEDERAL RESERVE SYSTEM (CONTINUED) CREDIT BY BANKS AND PERSONS OTHER THAN BROKERS...118 Bank arranging for extension of credit by corporation. (a) The Board...

2014-01-01

125

24 CFR 904.118 - Homeowners association-planned unit development (PUD).  

Code of Federal Regulations, 2012 CFR

24 Housing and Urban Development 4 2013-04-01 2013-04-01...Homeowners association-planned unit development (PUD). 904.118 Section 904.118 Housing and Urban Development OFFICE OF ASSISTANT SECRETARY...

2013-04-01

126

37 CFR 1.18 - Patent post allowance (including issue) fees.  

Code of Federal Regulations, 2012 CFR

37 Patents, Trademarks, and Copyrights 1 2012-07-01 2012-07-01 false Patent post allowance (including issue) fees. 1.18 Section 1.18 Patents, Trademarks, and Copyrights UNITED STATES PATENT AND TRADEMARK...

2012-07-01

127

37 CFR 1.18 - Patent post allowance (including issue) fees.  

Code of Federal Regulations, 2010 CFR

37 Patents, Trademarks, and Copyrights 1 2010-07-01 2010-07-01 false Patent post allowance (including issue) fees. 1.18 Section 1.18 Patents, Trademarks, and Copyrights UNITED STATES PATENT AND TRADEMARK...

2010-07-01

128

37 CFR 1.18 - Patent post allowance (including issue) fees.  

Code of Federal Regulations, 2011 CFR

37 Patents, Trademarks, and Copyrights 1 2011-07-01 2011-07-01 false Patent post allowance (including issue) fees. 1.18 Section 1.18 Patents, Trademarks, and Copyrights UNITED STATES PATENT AND TRADEMARK...

2011-07-01

129

Microstructure and segregation behavior of palladium in silver-copper-palladium alloys.  

PubMed

It has been reported that the addition of palladium can modify the microstructure and improve the properties of Ag-Cu eutectic alloy as well as admixed Cu-rich amalgam. The purpose of this work was to study the microstructure and segregation behavior of palladium in a series of Ag-Cu-Pd alloys. All microstructural and microchemical results consistently indicated a strong tendency for palladium to form the ordered Cu3Pd superlattice in the copper-rich phase of the present ternary alloys. Transmission electron microscopic examination indicated that, in addition to the large Cu-rich particles, numerous small (typically tens of nanometers) Cu-rich particles were distributed in the Ag-rich phase. In the alloys containing 10 and 15 wt% Pd, the Cu3Pd superlattice had an L1(2)-type crystal structure. In the alloy containing 20 wt% Pd, the Cu3Pd had a periodic (regular) APB structure. The solubility of palladium in the Cu-rich phase was always much larger than that in the Ag-rich phase. The ratio of the palladium concentration in the copper-rich phase to that in the silver-rich phase decreased with the overall palladium content. PMID:8876602

Chen, K I; Lin, J H; Ju, C P

1996-07-01

130

Viral-templated Palladium Nanocatalysts  

NASA Astrophysics Data System (ADS)

Despite recent progress on nanocatalysis, there exist several critical challenges in simple and readily controllable nanocatalyst synthesis including the unpredictable particle growth, deactivation of catalytic activity, cumbersome catalyst recovery and lack of in-situ reaction monitoring. In this dissertation, two novel approaches are presented for the fabrication of viral-templated palladium (Pd) nanocatalysts, and their catalytic activities for dichromate reduction reaction and Suzuki Coupling reaction were thoroughly studied. In the first approach, viral template based bottom-up assembly is employed for the Pd nanocatalyst synthesis in a chip-based format. Specifically, genetically displayed cysteine residues on each coat protein of Tobacco Mosaic Virus (TMV) templates provide precisely spaced thiol functionalities for readily controllable surface assembly and enhanced formation of catalytically active Pd nanoparticles. Catalysts with the chip-based format allow for simple separation and in-situ monitoring of the reaction extent. Thorough examination of synthesis-structure-activity relationship of Pd nanoparticles formed on surface-assembled viral templates shows that Pd nanoparticle size, catalyst loading density and catalytic activity of viral-templated Pd nanocatalysts can be readily controlled simply by tuning the synthesis conditions. The viral-templated Pd nanocatalysts with optimized synthesis conditions are shown to have higher catalytic activity per unit Pd mass than the commercial Pd/C catalysts. Furthermore, tunable and selective surface assembly of TMV biotemplates is exploited to control the loading density and location of Pd nanocatalysts on solid substrates via preferential electroless deposition. In addition, the catalytic activities of surface-assembled TMV-templated Pd nanocatalysts were also investigated for the ligand-free Suzuki Coupling reaction under mild reaction conditions. The chip-based format enables simple catalyst separation and reuse as well as facile product recovery. Reaction condition studies show that the solvent ratio played an important role in the selectivity of the Suzuki reaction, and that a higher water/acetonitrile ratio significantly facilitated the cross-coupling pathway. Meanwhile, in-depth characterizations including Atomic Force Microscopy (AFM), Grazing Incidence Small Angle X-ray Scattering (GISAXS), Inductively Coupled Plasma Optical Emission Spectrometry (ICP-OES) and X-ray Photoelectron Spectroscopy (XPS) were carried out for these chip-based viral-templated Pd nanocatalysts. In the second approach, catalytically active TMV-templated Pd nanoparticles are encapsulated in readily exploited polymeric microparticle formats. Specifically, small (1˜2 nm), uniform and highly crystalline palladium (Pd) nanoparticles are spontaneously formed along (TMV) biotemplates without external reducing agents. The as-prepared Pd-TMV complexes are integrated into the hybrid poly(ethylene glycol)(PEG)-based microparticles via replica molding (RM) technique in a simple, robust and highly reproducible manner. The Pd-TMV complex structure was characterized by Transmission Electron Microscopy (TEM). The hybrid Pd-TMV-PEG microparticles are examined to have high catalytic activity, recyclability and stability through dichromate reduction. Combined these findings represent a significant step toward simple, robust, scalable synthesis and fabrication of efficient biotemplate-supported Pd nanocatalysts in readily deployable polymeric formats with high capacity in a well-controlled manner. These two simple, robust and readily controllable approaches for the fabrication of viral-templated Pd nanocatalysts, in both chip-based and hydrogel-encapsulated formats, can be readily extended to a variety of other nano-bio hybrid material synthesis in other catalytic reaction systems.

Yang, Cuixian

131

21 CFR 118.1 - Persons covered by the requirements in this part.  

Code of Federal Regulations, 2011 CFR

...as defined in § 118.3, you must comply only with the refrigeration requirements in § 118.4(e) for production of eggs on...processing or egg products facilities, you must comply with the refrigeration requirements in § 118.4(e). This section applies...

2011-04-01

132

21 CFR 118.1 - Persons covered by the requirements in this part.  

Code of Federal Regulations, 2010 CFR

...as defined in § 118.3, you must comply only with the refrigeration requirements in § 118.4(e) for production of eggs on...processing or egg products facilities, you must comply with the refrigeration requirements in § 118.4(e). This section applies...

2010-04-01

133

42 CFR 435.118 - Infants and children under age 19.  

Code of Federal Regulations, 2013 CFR

...2013-10-01 2013-10-01 false Infants and children under age 19. 435.118 Section 435.118...Coverage Mandatory Coverage of Pregnant Women, Children Under 19, and Newborn Children § 435.118 Infants and children under...

2013-10-01

134

Hydrogen and Palladium Foil: Two Classroom Demonstrations  

ERIC Educational Resources Information Center

In these two classroom demonstrations, students observe the reaction between H[subscript 2] gas and Pd foil. In the first demonstration, hydrogen and palladium combine within one minute at 1 atm and room temperature to yield the non-stoichiometric, interstitial hydride with formula close to the maximum known value, PdH[subscript 0.7]. In the…

Klotz, Elsbeth; Mattson, Bruce

2009-01-01

135

Thermal behaviour of palladium complexing polyacrylamidoxime polymer  

Microsoft Academic Search

A fibrous material with metal complexing ability, suitable for retention, concentration and recovery of the palladium ions from acidic aqueous solutions, was prepared by partially converting the nitrile groups of a polyacrylonitrile fibre into amidoxime groups. The thermal behaviour of the resulting polyacrylamidoxime fibre in comparison with its polyacrylonitrile precursor, as well as that of the sorbent material after the

Gabriela Moroi; Nicolae Bâlb?

2001-01-01

136

Growth and sedimentation of fine particles produced in aqueous solutions of palladium sulfate and palladium sulfate-silver sulfate induced by gamma-ray irradiation.  

National Technical Information Service (NTIS)

It is known that palladium and palladium-silver fine particles were formed from deaerated aqueous solutions of palladium sulfate and palladium sulfate-silver sulfate induced by gamma-ray irradiation. Changes in particle size and with amount of particles i...

M. Hatada C. D. Jonah

1994-01-01

137

Characterization of Bombyx mori nucleopolyhedrovirus with a deletion of bm118.  

PubMed

Bombyx mori nucleopolyhedrovirus (BmNPV) ORF118 (bm118) is homologous to Autographa californica nucleopolyhedrovirus (AcMNPV) ORF142, one of the core genes existing in all baculovirus genomes sequenced to date, suggesting that Bm118 plays a critical role in viral infection. In this study, the primary role of Bm118 was investigated by using homologous recombination in Escherichia coli to generate a bm118 knockout bacmid containing the BmNPV genome. In addition, the bm118 rescue bacmid was constructed by transposing a bm118 gene cassette into the polh locus of the bm118 knockout bacmid. Transfection assays demonstrated that the bm118 knockout bacmid was incapable of producing budded virion (BV). Nevertheless, this defect could be partially recovered by a rescue bacmid. Electron microscopy analysis revealed that the bm118 knockout produced aberrant capsids characterized by translucent, elongated nucleocapsids present as bundles within the nuclei. This construct also produced polyhedra lacking virions. These results reveal that Bm118 is essential for BV production and nucelocapsid maturation. PMID:18462822

Yang, Zhang-Nv; Xu, Hai-Jun; Park, Enoch Y; Zhang, Chuan-Xi

2008-08-01

138

41 CFR 102-118.65 - Can my agency receive electronic billing for payment of transportation services?  

Code of Federal Regulations, 2013 CFR

...agency receive electronic billing for payment of transportation services? 102-118.65 Section 102-118...Continued) FEDERAL MANAGEMENT REGULATION TRANSPORTATION 118-TRANSPORTATION PAYMENT AND AUDIT Ordering and Paying...

2013-07-01

139

Devlopment of palladium\\/ceramic membranes for hydrogen separation  

Microsoft Academic Search

This paper presents the major objectives involved in the development of a thin-layer palladium\\/ceramic composite membranes. These are (a) electroless plating of palladium on ceramic substrate, (b) characterization of palladium\\/ceramic composite formed, (c) evaluation of selectivity of the composite membranes for hydrogen separation. Commercially available ceramic was used as substrate for deposition of hydrogen selective layers. The substrate was coated

E. David; J. Kopac

2011-01-01

140

The preparation of palladium for cold fusion experiments  

Microsoft Academic Search

Techniques have been established to prepare palladium specimens for cold fusion experiments using an ultra-high-vacuum, allmetal, high-temperature furnace to melt palladium metal in high purity alumina molds having a test tube shape. To date 6-mm and 15-mm cylinders have been fabricated, the latter being used to fabricate a sphere 12.5-mm in diameter. Techniques and facilities used for palladium-hydrogen isotope pressure-volume-temperature

G. L. Powell; J. S. Bullock; R. L. Hallman; P. J. Horton; D. P. Hutchinson

1990-01-01

141

Bidentate cycloimidate palladium complexes with aliphatic and aromatic anagostic bonds.  

PubMed

Palladium(ii) complexes of bidentate cycloimidate ligand systems with a triarylmethyl moiety exhibit exceptional downfield shifts in proton NMR spectra due to rare anagostic interactions. PMID:24764000

Schöler, Stephan; Wahl, Maike H; Wurster, Nicole I C; Puls, Arik; Hättig, Christof; Dyker, Gerald

2014-05-01

142

Palladium pincer complex-catalyzed allylic stannylation with hexaalkylditin reagents.  

PubMed

Palladium pincer complex (1)-catalyzed stannylation of allyl chloride, phosphonate, and epoxide substrates (4a-h) could be performed with hexaalkylditin reagents (3) under mild neutral reaction conditions. This catalytic reaction proceeds via palladium(II) intermediates without involvement of allyl-palladium complexes, and therefore the allylstannane product does not interfere with the palladium catalyst. Use of a combined catalytic system (1 + 2) allowed the development of an effective one-pot procedure for allylation of aldehyde and imine electrophiles. [reaction: see text] PMID:15151425

Wallner, Olov A; Szabó, Kálmán J

2004-05-27

143

Process for recovery of palladium from nuclear fuel reprocessing wastes  

DOEpatents

Palladium is selectively removed from spent nuclear fuel reprocessing waste by adding sugar to a strong nitric acid solution of the waste to partially denitrate the solution and cause formation of an insoluble palladium compound. The process includes the steps of: (a) adjusting the nitric acid content of the starting solution to about 10 M, (b) adding 50% sucrose solution in an amount sufficient to effect the precipitation of the palladium compound, (c) heating the solution at reflux temperature until precipitation is complete, and (d) centrifuging the solution to separate the precipitated palladium compound from the supernatant liquid.

Campbell, David O. (Oak Ridge, TN); Buxton, Samuel R. (Wartburg, TN)

1981-01-01

144

Process for recovery of palladium from nuclear fuel reprocessing wastes  

DOEpatents

Palladium is selectively removed from spent nuclear fuel reprocessing waste by adding sugar to a strong nitric acid solution of the waste to partially denitrate the solution and cause formation of an insoluble palladium compound. The process includes the steps of: (a) adjusting the nitric acid content of the starting solution to about 10 M; (b) adding 50% sucrose solution in an amount sufficient to effect the precipitation of the palladium compound; (c) heating the solution at reflux temperature until precipitation is complete; and (d) centrifuging the solution to separate the precipitated palladium compound from the supernatant liquid.

Campbell, D.O.; Buxton, S.R.

1980-06-16

145

41 CFR 102-118.290 - Must every electronic and paper transportation bill undergo a prepayment audit?  

Code of Federal Regulations, 2013 CFR

... false Must every electronic and paper transportation bill undergo a prepayment audit? 102-118...Continued) FEDERAL MANAGEMENT REGULATION TRANSPORTATION 118-TRANSPORTATION PAYMENT AND AUDIT Prepayment Audits of...

2013-07-01

146

Intramolecular reductive elimination of methane from a dinuclear palladium complex containing methyl and hydride on adjacent palladium centers  

SciTech Connect

The preparation, isolation, and determination of structure of a dinuclear palladium complex containing methyl and hydride on adjacent palladium atoms its facile 1,1-dinuclear intramolecular elimination of methane are reported. The complex was isolated as its tetraphenylborate salt and was fully characterized including its x-ray structure. Reductive elimination from the deuterated complex containing deutride on one palladium and trideuteriomethyl on the other gave a quantitative yield of methane. 16 references, 3 figures.

Kellenberger, B.; Young, S.J.; Stille, J.K.

1985-01-01

147

Mechanism of Cataract Formation in ?A-crystallin Y118D Mutation  

PubMed Central

Purpose The aim of this study was to elucidate the molecular mechanisms that lead to a dominant nuclear cataract in a mouse harboring the Y118D mutation in the ?A-crystallin gene. Methods The physicochemical properties of ?-crystallin obtained from mouse lenses with the Y118D mutation as well as a recombinant Y118D ?A-crystallin were studied using gel filtration, two-dimensional (2D) gel electrophoresis, multi-angle light scattering, circular dichroism, fluorescence, and chaperone activities. Results Both native ?-crystallin from mutant lens and recombinant ?A-Y118D displayed higher molecular mass distribution than the wild-type. Circular dichroism spectra indicated changes in the secondary structures of ?A-Y118D. The ?A-Y118D protein prevented nonspecific protein aggregation more effectively than wild-type ?A-crystallin. The gel filtration and 2D gel electrophoresis analysis showed a significant reduction of Y118D mutant protein in comparison with wild-type ?A protein of heterozygous mutant lenses. Quantitative RT-PCR results confirmed a decrease in ?A and ?B transcripts in the homozygous mutant ? A(Y118D/Y118D) lenses. Conclusions The ?A-Y118D mutant protein itself displays an increased chaperone-like activity. However, the dominant nuclear cataract is associated with a significant decrease in the amount of ?A-crystallin, leading to a reduction in total chaperone capacity needed for maintaining lens transparency.

Huang, Qingling; Ding, Linlin; Phan, Kim B.; Cheng, Catherine; Xia, Chun-hong; Gong, Xiaohua; Horwitz, Joseph

2010-01-01

148

Palladium-catalyzed amination of aryl nonaflates.  

PubMed

The first detailed study of the palladium-catalyzed amination of aryl nonaflates is reported. Use of ligands 2-4 and 6 allows for the catalytic amination of electron-rich and -neutral aryl nonaflates with both primary and secondary amines. With use of Xantphos 5, the catalytic amination of a variety of functionalized aryl nonaflates resulted in excellent yields of anilines; even 2-carboxymethyl aryl nonaflate is effectively coupled with a primary alkylamine. Moderate yields were obtained when coupling halo-aryl nonaflates with a variety of amines, where in most cases the aryl nonaflate reacted in preference to the aryl halide. Overall, aryl nonaflates are an effective alternative to triflates in palladium-catalyzed C-N bond-forming processes due to their increased stability under the reaction conditions. PMID:14656080

Anderson, Kevin W; Mendez-Perez, Maria; Priego, Julian; Buchwald, Stephen L

2003-12-12

149

Palladium103 brachytherapy for prostate carcinoma  

Microsoft Academic Search

Purpose: A report of biochemical outcomes for patients treated with palladium-103 (Pd-103) brachytherapy over a fixed time interval.Methods and Materials: Two hundred thirty patients with clinical stage T1–T2 prostate cancer were treated with Pd-103 brachytherapy and followed with prostate-specific antigen (PSA) determinations. Kaplan-Meier estimates of biochemical failure on the basis of two consecutive elevations of PSA were utilized. Multivariate risk

John C Blasko; Peter D Grimm; John E Sylvester; Kas Ray Badiozamani; David Hoak; William Cavanagh

2000-01-01

150

Neutron Measurement of Magnetization Density in Palladium  

NASA Astrophysics Data System (ADS)

The magnetization density induced in palladium by an applied magnetic field was measured by polarized neutron diffraction. The measurements were taken with the sample at 4.2 K in an applied field of 57.2 kOe and include the innermost eleven Bragg reflections. The observed density is contracted by about 15% relative to that calculated for Pd+2 by the Hartree-Fock method, and shows an asphericity similar to that of isoelectronic Ni.

Cable, J. W.; Wollan, E. O.; Felcher, G. P.; Brun, T. O.; Hornfeldt, S. P.

1975-02-01

151

Methanol synthesis over palladium supported on silica  

Microsoft Academic Search

Methanol synthesis activity of palladium supported on four types of silica (Davison 01, 03, 57, and 59) were evaluated at 16 atm and 255°C in a Berty-type reactor. Turnover frequencies (TOF) were determined based on hydrogen chemisorption data. The TOF's for a particular type of silica increased with decreasing metal dispersion, but for equivalent dispersions the silicas had a marked

K. P. Kelly; T. Tatsumi; T. Uematsu; D. J. Driscoll; J. H. Lunsford

1986-01-01

152

Mechanism of action of a palladium modifier  

NASA Astrophysics Data System (ADS)

The mechanism of low-temperature migration of analytes onto a palladium modifier and the mechanism of analyte retention on palladium in the pyrolysis stage have been interpreted on the basis of the method of absolute reaction rates and the mechanism of dissociative evaporation of solids. As has been shown previously by the author, the decomposition of solids, in particular, metal nitrates, occurs through the congruent gasification of all reaction products, irrespective of their saturated pressure (with the simultaneous condensation of low-volatility species). In the interval between gasification and condensation, these species could diffuse for some distance from the primary site. An application of the method of absolute reaction rates (the Hertz-Langmuir vaporization models) to the kinetics of analyte release in the presence of a palladium modifier permits the interpretation of the retention mechanism as dissociative chemisorption. The experimental data from the literature (the appearance temperatures and activation energies for Ag, As, Au, Bi, Cd, Cu, Se and Tl) were used in these calculations.

L'vov, Boris V.

2000-11-01

153

Palladium-catalyzed oxidative carbonylation reactions.  

PubMed

Palladium-catalyzed coupling reactions have become a powerful tool for advanced organic synthesis. This type of reaction is of significant value for the preparation of pharmaceuticals, agrochemicals, as well as advanced materials. Both, academic as well as industrial laboratories continuously investigate new applications of the different methodologies. Clearly, this area constitutes one of the major topics in homogeneous catalysis and organic synthesis. Among the different palladium-catalyzed coupling reactions, several carbonylations have been developed and widely used in organic syntheses and are even applied in the pharmaceutical industry on ton-scale. Furthermore, methodologies such as the carbonylative Suzuki and Sonogashira reactions allow for the preparation of interesting building blocks, which can be easily refined further on. Although carbonylative coupling reactions of aryl halides have been well established, palladium-catalyzed oxidative carbonylation reactions are also interesting. Compared with the reactions of aryl halides, oxidative carbonylation reactions offer an interesting pathway. The oxidative addition step could be potentially avoided in oxidative reactions, but only few reviews exist in this area. In this Minireview, we summarize the recent development in the oxidative carbonylation reactions. PMID:23307763

Wu, Xiao-Feng; Neumann, Helfried; Beller, Matthias

2013-02-01

154

Phosphorylation of histone H3(T118) alters nucleosome dynamics and remodeling.  

PubMed

Nucleosomes, the fundamental units of chromatin structure, are regulators and barriers to transcription, replication and repair. Post-translational modifications (PTMs) of the histone proteins within nucleosomes regulate these DNA processes. Histone H3(T118) is a site of phosphorylation [H3(T118ph)] and is implicated in regulation of transcription and DNA repair. We prepared H3(T118ph) by expressed protein ligation and determined its influence on nucleosome dynamics. We find H3(T118ph) reduces DNA-histone binding by 2 ?kcal/mol, increases nucleosome mobility by 28-fold and increases DNA accessibility near the dyad region by 6-fold. Moreover, H3(T118ph) increases the rate of hMSH2-hMSH6 nucleosome disassembly and enables nucleosome disassembly by the SWI/SNF chromatin remodeler. These studies suggest that H3(T118ph) directly enhances and may reprogram chromatin remodeling reactions. PMID:21576235

North, Justin A; Javaid, Sarah; Ferdinand, Michelle B; Chatterjee, Nilanjana; Picking, Jonathan W; Shoffner, Matthew; Nakkula, Robin J; Bartholomew, Blaine; Ottesen, Jennifer J; Fishel, Richard; Poirier, Michael G

2011-08-01

155

Rapid response microsensor for hydrogen detection using nanostructured palladium films  

Microsoft Academic Search

Most palladium thin film based hydrogen gas sensors have response and recovery times that are too long to make them useful in vehicular and stationary gas leak detection applications. In contrast, a nanostructured palladium thin film based microcantilever (MC) hydrogen gas microsensor is reported herein with near ideal response characteristics for use in these hydrogen economy related applications. Specifically, a

James F. Patton; Scott R. Hunter; Michael J. Sepaniak; Panos G. Daskos; D. Barton Smith

2010-01-01

156

Rapid Responding PalladiumSilver Surface Modified Microsensor for Hydrogen  

Microsoft Academic Search

Most palladium thin film based hydrogen gas sensors have response and recovery times that are too long to make them useful in vehicular and stationary gas leak detection applications. In contrast, a palladium-silver thin film based microcantilever (MC) hydrogen gas microsensor is reported herein with near ideal response characteristics for use in these hydrogen economy related applications. Specifically, 3-10 second

James Patton; Scott Robert Hunter; Michael Sepaniak; Panos G Datskos; Barton Smith

2010-01-01

157

Oxidation of CO on hydrogen-loaded palladium  

Microsoft Academic Search

The oxidation of CO adsorbed on the surface of palladium electrodes loaded with different amounts of hydrogen was studied by single potential alteration infrared reflectance spectroscopy (SPAIRS). In the absence of hydrogen, only CO2 was detected during anodic oxidation of CO. Adsorption of CO in the presence of hydrogen in palladium led to a more negative onset of its electrooxidation,

O. YÉPEZ; B. R. Scharifker

1999-01-01

158

Support and water effects on palladium based methane combustion catalysts  

Microsoft Academic Search

The effect of the support (?-alumina and zirconia) and of the presence of water on the catalytic activity of palladium particles was investigated both on oxidized and reduced states using temperature programmed reaction (TPR). The support was found to influence the onset and the rate of the reoxidation process. The particle size of the palladium phase, however, strongly influenced the

Dragos Ciuparu; Lisa Pfefferle

2001-01-01

159

Effect of Palladium Form on Tetraphenylborate Decomposition Rate  

SciTech Connect

Palladium catalyzes the decomposition of tetraphenylborate in alkaline solutions. Researchers postulate several decomposition mechanisms that differ in the form of the palladium catalyst. Potential forms include solid and soluble, different soluble species (such as aqueous or organic soluble), and different oxidation states (i.e., 0, II, and IV). Initial tests measured the reactivity and distribution of four Pd forms in tetraphenylborate slurries.

Walker, D.D. [Westinghouse Savannah River Company, AIKEN, SC (United States)

1998-04-28

160

Size and geometric effects in copper and palladium metal clusters  

Microsoft Academic Search

Size and geometric effects in copper and palladium metal clusters of up to 40 atoms, when studied by the extended Hueckel theory, showed the effects of cluster shape on the valence density of states of palladium, but not of copper. Graphs, tables, and 29 references.

R. C. Baetzold

1978-01-01

161

Pulsed electrodeposition of palladium nanowire arrays using AAO template  

Microsoft Academic Search

Highly ordered palladium (Pd) nanowire arrays were successfully prepared by pulsed electrodeposition (PED) method using anodized aluminum oxide (AAO) nanotemplate. The Pd nanowire arrays are standing freely on a titanium-coated silicon wafer after removing the AAO template. The titanium film is used for providing conducting surface for the electrodeposition of palladium and also for removing alumina barrier layer formed as

Kyungtae Kim; Moonjung Kim; Sung M. Cho

2006-01-01

162

High-valent palladium fluoride complexes and uses thereof  

US Patent & Trademark Office Database

The present invention provides novel high-valent palladium fluoride complexes. The complexes typically include multi-dentate ligands that stabilize the octahedral coordination sphere of the palladium(IV) atom. These complexes are useful in fluorinating organic compounds, in particular aryl-containing compounds. The invention is particularly useful for fluorinating compounds with .sup.19F for PET imaging.

2014-04-01

163

Hydrogen Sensors and Switches from Electrodeposited Palladium Mesowire Arrays  

Microsoft Academic Search

Hydrogen sensors and hydrogen-activated switches were fabricated from arrays of mesoscopic palladium wires. These palladium ``mesowire'' arrays were prepared by electrodeposition onto graphite surfaces and were transferred onto a cyanoacrylate film. Exposure to hydrogen gas caused a rapid (less than 75 milliseconds) reversible decrease in the resistance of the array that correlated with the hydrogen concentration over a range from

Frédéric Favier; Erich C. Walter; Michael P. Zach; Thorsten Benter; Reginald M. Penner

2001-01-01

164

CONTENT OF PLATINUM AND PALLADIUM IN RAT TISSUE: CORRELATION OF TISSUE CONCENTRATION OF PLATINUM AND PALLADIUM WITH BIOCHEMICAL EFFECTS  

EPA Science Inventory

Platinum and palladium are used as the active components in the catalytic converters of air pollution control devices of motor vehicles. The use of these metals is accompanied by the potential loss of platinum and palladium into the environment. This laboratory has been involved ...

165

Recovery of macroinvertebrates by screening in the field: a comparison between coarse (1.18 mm) and fine (0.60 mm) mesh sieves  

USGS Publications Warehouse

We evaluated the potential loss of target benthic macroinvertebrates from coarse-mesh field wash down of samples through a 1.18-mm mesh sieve nested on a 0.60-mm mesh sieve. Visible target organisms (midges, mayflies, and fingernail clams) in the 1.18-mm mesh sieve were removed from the sample and enumerated in the field. The entire contents of both sieves were preserved for subsequent laboratory enumeration under 4X magnification. Percent recoveries from each treatment were based on total intact organisms found in all sieves. Percent recovery for fingernail clams found in the field (31%) was lower than for mayflies (79%) and midges (88%). Laboratory enumeration of organisms retained by the 1.18-mm sieve yielded additional fingernail clams (to total 74% recovered in the field and lab), mayflies (to total 89%), and midges (to total 91%). If the 1.18-mm sieve is used alone in the field, it is adequate to monitor mayflies, midges >1 cm, and adult fingernail clams greater than or equal to 5.0 mm shell length.

Dukerschein, J. T.; Gent, R.; Sauer, J.

1996-01-01

166

A novel lead compound CM-118: Antitumor activity and new insight into the molecular mechanism and combination therapy strategy in c-Met- and ALK-dependent cancers.  

PubMed

The anaplastic lymphoma kinase (ALK) and the c-Met receptor tyrosine kinase play essential roles in the pathogenesis in multiple human cancers and present emerging targets for cancer treatment. Here, we describe CM-118, a novel lead compound displaying low nanomolar biochemical potency against both ALK and c-Met with selectivity over>90 human kinases. CM-118 potently abrogated hepatocyte growth factor (HGF)-induced c-Met phosphorylation and cell migration, phosphorylation of ALK, EML4-ALK, and ALK resistance mutants in transfected cells. CM-118 inhibited proliferation and/or induced apoptosis in multiple c-Met- and ALK-addicted cancer lines with dose response profile correlating target blockade. We show that the CM-118-induced apoptosis in c-Met-amplified H1993 NSCLC cells involved a rapid suppression of c-Met activity and c-Met-to-EGFR cross-talk, and was profoundly potentiated by EGFR inhibitors as shown by the increased levels of apoptotic proteins cleaved-PARP and Bim as well as reduction of the survival protein Mcl-1. Bim-knockdown or Mcl-1 overexpression each significantly attenuated apoptosis. We also revealed a key role by mTOR in mediating CM-118 action against the EML4-ALK-dependent NSCLC cells. Abrogation of EML4-ALK in H2228 cells profoundly reduced signaling capacity of the rapamycin-sensitive mTOR pathway leading to G 1 cell cycle arrest and mitochondrial hyperpolarization, a metabolic perturbation linked to mTOR inhibition. Depletion of mTOR or mTORC1 inhibited H2228 cell growth, and mTOR inhibitors potentiated CM-118's antitumor activity in vitro and in vivo. Oral administration of CM-118 at a wide range of well tolerated dosages diminished c-Met- and ALK phosphorylation in vivo, and caused tumor regression or growth inhibition in multiple c-Met- and ALK-dependent tumor xenografts in mice. CM-118 exhibits favorable pharmacokinetic and drug metabolism properties hence presents a candidate for clinical evaluation. PMID:24618813

Meng, Lanfang; Shu, Mengjun; Chen, Yaqing; Yang, Dexiao; He, Qun; Zhao, Hui; Feng, Zhiyong; Liang, Chris; Yu, Ker

2014-06-01

167

Effect of Lactobacillus salivarius Bacteriocin Abp118 on the Mouse and Pig Intestinal Microbiota  

PubMed Central

Lactobacilli are Gram-positive bacteria that are a subdominant element in the human gastrointestinal microbiota, and which are commonly used in the food industry. Some lactobacilli are considered probiotic, and have been associated with health benefits. However, there is very little culture-independent information on how consumed probiotic microorganisms might affect the entire intestinal microbiota. We therefore studied the impact of the administration of Lactobacillus salivarius UCC118, a microorganism well characterized for its probiotic properties, on the composition of the intestinal microbiota in two model animals. UCC118 has anti-infective activity due to production of the bacteriocin Abp118, a broad-spectrum class IIb bacteriocin, which we hypothesized could impact the microbiota. Mice and pigs were administered wild-type (WT) L. salivarius UCC118 cells, or a mutant lacking bacteriocin production. The microbiota composition was determined by pyrosequencing of 16S rRNA gene amplicons from faeces. The data show that L. salivarius UCC118 administration had no significant effect on proportions of major phyla comprising the mouse microbiota, whether the strain was producing bacteriocin or not. However, L. salivarius UCC118 WT administration led to a significant decrease in Spirochaetes levels, the third major phylum in the untreated pig microbiota. In both pigs and mice, L. salivarius UCC118 administration had an effect on Firmicutes genus members. This effect was not observed when the mutant strain was administered, and was thus associated with bacteriocin production. Surprisingly, in both models, L. salivarius UCC118 administration and production of Abp118 had an effect on Gram-negative microorganisms, even though Abp118 is normally not active in vitro against this group of microorganisms. Thus L. salivarius UCC118 administration has a significant but subtle impact on mouse and pig microbiota, by a mechanism that seems at least partially bacteriocin-dependent.

Riboulet-Bisson, Eliette; Sturme, Mark H. J.; Jeffery, Ian B.; O'Donnell, Michelle M.; Neville, B. Anne; Forde, Brian M.; Claesson, Marcus J.; Harris, Hugh; Gardiner, Gillian E.; Casey, Patrick G.; Lawlor, Peadar G.; O'Toole, Paul W.; Ross, R. Paul

2012-01-01

168

Polychlorinated biphenyl (118) activates osteoclasts and induces bone resorption in goldfish.  

PubMed

To analyze the effect of polychlorinated biphenyl (PCB) 118 on fish bone metabolism, we examined osteoclastic and osteoblastic activities, as well as plasma calcium levels, in the scales of PCB (118)-injected goldfish. In addition, effect of PCB (118) on osteoclasts and osteoblasts was investigated in vitro. Immature goldfish, in which the endogenous effects of sex steroids are negligible, were used. PCB (118) was solubilized in dimethyl sulfoxide at a concentration of 10 ppm. At 1 and 2 days after PCB (118) injection (100 ng/g body weight), both osteoclastic and osteoblastic activities, and plasma calcium levels were measured. In an in vitro study, then, both osteoclastic and osteoblastic activities as well as each marker mRNA expression were examined. At 2 days, scale osteoclastic activity in PCB (118)-injected goldfish increased significantly, while osteoblastic activity did not change significantly. Corresponding to osteoclastic activity, plasma calcium levels increased significantly at 2 days after PCB (118) administration. Osteoclastic activation also occurred in the marker enzyme activities and mRNA expressions in vitro. Thus, we conclude that PCB (118) disrupts bone metabolism in goldfish both in vivo and in vitro experiments. PMID:23247518

Yachiguchi, Koji; Matsumoto, Noriko; Haga, Yuki; Suzuki, Motoharu; Matsumura, Chisato; Tsurukawa, Masahiro; Okuno, Toshihiro; Nakano, Takeshi; Kawabe, Kimi; Kitamura, Kei-Ichiro; Toriba, Akira; Hayakawa, Kazuichi; Chowdhury, Vishwajit S; Endo, Masato; Chiba, Atsuhiko; Sekiguchi, Toshio; Nakano, Masaki; Tabuchi, Yoshiaki; Kondo, Takashi; Wada, Shigehito; Mishima, Hiroyuki; Hattori, Atsuhiko; Suzuki, Nobuo

2014-05-01

169

26 CFR 1.118-2 - Contribution in aid of construction.  

Code of Federal Regulations, 2013 CFR

...2013-04-01 false Contribution in aid of construction. 1.118-2 Section...Income § 1.118-2 Contribution in aid of construction. (a) Special rule... (i) The amount is a contribution in aid of construction under paragraph (b)...

2013-04-01

170

Cleanup Verification Package for the 118-F-5 PNL Sawdust Pit  

SciTech Connect

This cleanup verification package documents completion of remedial action, sampling activities, and compliance with cleanup criteria for the 118-F-5 Burial Ground, the PNL (Pacific Northwest Laboratory) Sawdust Pit. The 118-F-5 Burial Ground was an unlined trench that received radioactive sawdust from the floors of animal pens in the 100-F Experimental Animal Farm.

L. D. Habel

2008-05-20

171

Cleanup Verification Package for the 118-B-6, 108-B Solid Waste Burial Ground  

SciTech Connect

This cleanup verification package documents completion of remedial action for the 118-B-6, 108-B Solid Waste Burial Ground. The 118-B-6 site consisted of 2 concrete pipes buried vertically in the ground and capped by a concrete pad with steel lids. The site was used for the disposal of wastes from the "metal line" of the P-10 Tritium Separation Project.

M. L. Proctor

2006-06-13

172

41 CFR 102-118.340 - How does my agency contact the GSA Audit Division?  

Code of Federal Regulations, 2013 CFR

...2013-07-01 false How does my agency contact the GSA Audit Division? 102-118.340... § 102-118.340 How does my agency contact the GSA Audit Division? Your agency may contact the GSA Audit Division by writing...

2013-07-01

173

Palladium Electrodes for Molecular Tunnel Junctions  

PubMed Central

Gold has been the metal of choice for research on molecular tunneling junctions, but it is incompatible with CMOS fabrication because it forms deep level traps in silicon. Palladium electrodes do not contaminate silicon, and also give higher tunnel current signals in the molecular tunnel junctions we have studied. The result is cleaner signals in a recognition-tunneling junction that recognizes the four natural DNA bases as well as 5-methyl cytosine, with no spurious background signals. More than 75% of all the recorded signal peaks call the base correctly.

Chang, Shuai; Sen, Suman; Zhang, Peiming; Gyarfas, Brett; Ashcroft, Brian; Lefkowitz, Steven; Peng, Hongbo; Lindsay, Stuart

2012-01-01

174

Palladium-catalyzed direct arylation of selenophene.  

PubMed

An efficient and convenient method was developed for the regioselective formation of 2-aryl- or 2,5-diarylselenophenes via a palladium-catalyzed direct arylation. This protocol is suitable for a wide range of aryl halides containing different functional groups. The 2-arylated substrates can undergo an additional regioselective direct arylation event furnishing symmetrical or unsymmetrical 2,5-diaryl selenophenes in good yield. Competition experiments and the role of the acid additive are in agreement with a concerted metalation deprotonation (CMD) pathway. PMID:24893620

Rampon, Daniel S; Wessjohann, Ludger A; Schneider, Paulo H

2014-07-01

175

Direct Observation of Paramagnons in Palladium  

SciTech Connect

We report an inelastic neutron scattering study of the spin fluctuations in the nearly ferromagnetic element palladium. Dispersive over-damped collective magnetic excitations or 'paramagnons' are observed up to 128 meV. We analyze our results in terms of a Moriya-Lonzarich-type spin-fluctuation model and estimate the contribution of the spin fluctuations to the low-temperature heat capacity. In spite of the paramagnon excitations being relatively strong, their relaxation rates are large. This leads to a small contribution to the low-temperature electronic specific heat.

Doubble, R. [University of Bristol, UK; Hayden, S M. [University of Bristol, UK; Dai, Pengcheng [University of Tennessee, Knoxville (UTK); Mook Jr, Herbert A [ORNL; Thompson, James R [ORNL; Frost, C. [ISIS Facility, Rutherford Appleton Laboratory

2010-01-01

176

Scalable synthesis of nanoporous palladium powders.  

SciTech Connect

Nanoporous palladium powders are synthesized on milligram to gram scales by chemical reduction of tetrachloro complexes by ascorbate in a concentrated aqueous surfactant at temperatures between -20 and 30 C. Particle diameters are approximately 50 nm, and each particle is perforated by 3 nm pores, as determined by electron tomography. These materials are of potential value for storage of hydrogen isotopes and electrical charge; producing them at large scales in a safe and efficient manner will help realize this. A slightly modified procedure also results in nanoporous platinum.

Robinson, David B.; Tran, Kim L.; Clift, W. Miles; Arslan Ilke; Langham, Mary Elizabeth; Ong, Markus D.; Fares, Stephen James

2009-03-01

177

Tritium evolution from various morphologies of palladium  

SciTech Connect

The authors have been able to extend the tritium production techniques to various novel morphologies of palladium. These include small solid wires of various diameters and a type of pressed powder wire and a plasma cell. In most successful experiments, the amount of palladium required, for an equivalent tritium output, has been reduced by a factor of 100 over the older powder methods. In addition, they have observed rates of tritium production (>5 nCi/h) that far exceed most of the previous results. Unfortunately, the methods that they currently use to obtain the tritium are poorly understood and consequently there are numerous variables that need to be investigated before the new methods are as reliable and repeatable as the previous techniques. For instance, it seems that surface and/or bulk impurities play a major role in the successful generation of any tritium. In those samples with total impurity concentrations of >400 ppM essentially no tritium has been generated by the gas loading and electrical simulation methods.

Tuggle, D.G.; Claytor, T.N. [Los Alamos National Lab., NM (United States); Taylor, S.F. [Los Alamos National Lab., NM (United States)]|[Brigham Young Univ., Provo, UT (United States)

1994-04-01

178

Phosphorylation of estrogen receptor ? at serine 118 is correlated with breast cancer resistance to tamoxifen  

PubMed Central

The aim of the present study was to explore the correlation between estrogen receptor ? (ER?) phosphorylation at serines 118 and 167 and the responsiveness of patients with primary breast cancer to tamoxifen. Tumors from 104 patients with primary breast cancer who received adjuvant tamoxifen therapy at The Affiliated Cancer Hospital of Shantou University Medical College between January 2001 to December 2007 were subjected to immunohistochemical analysis with specific antibodies against ER? phosphorylated at either serine 118 (pER?-S118) and/or serine 167 (pER?-S167). ER? phosphorylation at the two sites was correlated with either the disease-free survival or the overall survival rate of these patients using the Kaplan-Meier survival analysis. pER?-S118 and pER?-S167 were found to be expressed in the cell nucleus of 25.0% (26/104) and 26.9% (28/104) of breast cancers, respectively. The expression of pER?-S118 was positively correlated with the human epidermal growth factor receptor-2 (HER-2) status (?2=6.85, P=0.01). The Kaplan-Meier analysis revealed a poorer disease-free (P=0.022) and overall survival (P=0.013) in breast cancer patients expressing pER?-S118, but not in those expressing pER?-S167. In conclusion, pER?-S118 was correlated with the HER-2 status and predicted breast cancer resistance to tamoxifen.

CHEN, MING; CUI, YU-KUN; HUANG, WEN-HE; MAN, KWAN; ZHANG, GUO-JUN

2013-01-01

179

Improved dispensing targets for ion beam particle generators  

NASA Technical Reports Server (NTRS)

Beam impinges on palladium-silver tube, which is target, and heats impinged surface causing local hot spot. Contained gas diffuses through hot spot to meet incoming beam and produce desired particles. When beam is turned off, target spot cools and stops dispensing contained gas.

Miller, C. G.

1974-01-01

180

Comparative Methylation Chemistry of Platinum, Palladium, Lead, and Manganese.  

National Technical Information Service (NTIS)

A study was carried out to evaluate the potential for platinum, palladium, lead, and manganese salts and oxides to be biochemically methylated. Methylation is an important, well recognized, determinant of metal toxicity; the striking example being the ext...

R. T. Taylor

1976-01-01

181

Palladium coated porous anodic alumina membranes for gas reforming processes  

NASA Astrophysics Data System (ADS)

Nanostructured ceramic membranes with ultrathin coatings of palladium metal have been demonstrated to separate hydrogen gas from a gas mixture containing nitrogen with 10% carbon dioxide and 10% hydrogen at temperatures up to 550 °C. The mechanically robust and thermally durable membranes were fabricated using a combination of conventional and high-efficiency anodisation processes on high purity aluminium foils. A pH-neutral plating solution has also been developed to enable electroless deposition of palladium metal on templates which were normally prone to chemical corrosion in strong acid or base environment. Activation and thus seeding of palladium nuclei on the surface of the template were essential to ensure uniform and fast deposition, and the thickness of the metal film was controlled by time of deposition. The palladium coated membranes showed improved hydrogen selectivity with increased temperature as well as after prolonged exposure to hydrogen, demonstrating excellent potential for gas separation technologies.

Wu, Jeremy P.; Brown, Ian W. M.; Bowden, Mark E.; Kemmitt, Timothy

2010-11-01

182

Leaching kinetics of platinum and palladium from spent automotive catalysts  

SciTech Connect

Empirical rate expressions for both platinum and palladium were obtained from mass balances and concentration-time data in a packed bed reactor using different (HCl):(HNO3) leaching solution concentration ratios. The spent catalysts used in this study (-60 + 70 mesh to -120 + 140 mesh) were analyzed to be 3791 ppm platinum and 1306 ppm palladium. High initial rates for both platinum and palladium were obtained for the early stages of leaching and were followed by rapid decay up to about 110 minutes and 50 minutes respectively. Typical concentrations in the leached solution were about 40 ppm Pt and 20 ppm Pd after about 5 hours for the experimental conditions used. The extent of reaction for platinum was in the 90 percent range while that of the palladium was in the 70 percent range.

Tyson, D.R.; Bautista, R.G.

1987-01-01

183

Palladium-based electrocatalysts and fuel cells employing such electrocatalysts  

DOEpatents

A direct organic fuel cell includes a fluid fuel comprising formic acid, an anode having an electrocatalyst comprising palladium nanoparticles, a fluid oxidant, a cathode electrically connected to the anode, and an electrolyte interposed between the anode and the cathode.

Masel; Richard I. (Champaign, IL), Zhu; Yimin (Urbana, IL), Larsen [Urbana, IL; Robert T. (Champaign, IL) [Champaign, IL

2010-08-31

184

Palladium-Catalyzed Synthesis of N-tert-Prenylindoles  

PubMed Central

Palladium-catalyzed N-tert-prenylation of indoles, tricarbonylchromium-activated indoles, and indolines that occur in high yields (up to 94%) with high tert-prenyl-to-n-prenyl selectivity (up to 12:1) are reported.

Johnson, Kirsten F.; Van Zeeland, Ryan

2013-01-01

185

Design and synthesis of thin palladium membranes for hydrogen separation  

SciTech Connect

The progress of electroless deposition of palladium around the pore area at surface of porous stainless steel was recorded in order to understand membrane formation and to control the membrane quality. A bridge structure is formed during the membrane formation around the pore area of the substrate. The porous substrate was modified to be smooth using micro-or nano-size metal or metal oxide particles in order to make sure that palladium membrane is strongly supported by the substrate and as the result the membrane thickness can be further reduced. The experimental results obtained from hydrogen permeation through the palladium membranes having the thickness from 400 nm to 18 {mu}m demonstrate that these thin membranes are solid and they can be used at the temperature of 550 deg.C and hydrogen pressure difference of 350 kPa. The proposed processing will allow optimizing the design and fabrication of thin palladium membranes for hydrogen separation. (authors)

Shi, Z.; Szpunar, J. A. [Dept. of Materials Engineering, McGill Univ., 3610 Univ., Montreal, QC H3A 2B2 (Canada); Wu, S. [AH2T Inc., 225 President Kennedy Avenue, PK6230, Montreal, QC H2X 3Y8 (Canada)

2008-07-15

186

Crossover behavior in hydrogen sensing mechanism for palladium ultrathin films.  

SciTech Connect

Palladium has been extensively studied as a material for hydrogen sensors because of the simplicity of its reversible resistance change when exposed to hydrogen gas. Various palladium films and nanostructures have been used, and different responses have been observed with these diverse morphologies. In some cases, such as with nanowires, the resistance will decrease, whereas in others, such as with thick films, the resistance will increase. Each of these mechanisms has been explored for several palladium structures, but the crossover between them has not been systematically investigated. Here we report on a study aimed at deciphering the nanostructure-property relationships of ultrathin palladium films used as hydrogen gas sensors. The crossover in these films is observed at a thickness of {approx} 5 nm. Ramifications for future sensor developments are discussed.

Darling, S. B.; Ramanathan, M.; Skudlarek, G.; Wang, H. H.; Illinois Math and Science Academy

2010-01-01

187

Palladium-coated fiber-taper hydrogen sensor: temperature response  

Microsoft Academic Search

We report an experimental study of the response of a hydrogen sensor based on a palladium-coated tapered optical fiber, at different temperatures in the range [-30, 80]°C. The main features of the sensor's response have been correlated with the pressure-composition isotherms of the Pd-H system and its phase transitions. Moreover, heating of the palladium layer optically with an auxiliary laser

D. Zalvidea; Antonio Diez; J. L. Cruz; M. V. Andres

2005-01-01

188

Nanocontact-induced catalytic activation in palladium nanoparticles  

Microsoft Academic Search

We report the synthesis and catalytic studies of novel palladium nanostructures assembled from small nanoparticles by a surfactant-templated method. These one-dimensional nanomaterials comprise high-density nanocontacts of ~1 nm in contact length at the particle-particle interface. In contrast to dispersed Pd nanoparticles (~5 nm), the polycrystalline palladium nanowires exhibit enhanced (~200 times) catalytic reactivity towards carbon-carbon cross-couplings under mild conditions. Theoretical

Changlong Jiang; Sadananda Ranjit; Zhongyu Duan; Yu Lin Zhong; Kian Ping Loh; Chun Zhang; Xiaogang Liu

2009-01-01

189

A novel palladium-catalyzed intramolecular redox reaction.  

PubMed

[reaction: see text] A new type of palladium-catalyzed redox reaction is described, forming enones from 2-(2-bromobenzyl)-ketones with an overall loss of HBr. The scope and limitations of the reaction are demonstrated by a series of cyclic and acyclic substrates. The mechanism most probably involves the formation of an intramolecular arylpalladium enolate and is related to the oxidation of silyl enol ethers with palladium acetate. PMID:11388850

Högenauer, K; Mulzer, J

2001-05-17

190

FASTGAS: Fast Gas Sampling for palladium exchange tests  

SciTech Connect

A mass spectrometric technique for measuring the composition of gas flows in rapid H/D exchange reactions in palladium compacts has been developed. This method, called FASTGAS (Fast Gas Sampling)'' has been used at atmospheric pressures and above with a time response of better than 100 ms. The current implementation of the FASTGAS technique is described in detail and examples of its application to palladium hydride exchange tests are given. 12 refs., 10 figs.

Malinowski, M.E.; Stewart, K.D.; VerBerkmoes, A.A.

1991-06-01

191

Palladium(0) mediated coupling of bromophosphaalkenes with Grignard reagents  

Microsoft Academic Search

Attempts to subject the phosphaalkene Mes* PCBr2 (1) (Mes* = supermesityl = 2,4,6-tri-tert-butylphenyl) to a palladium(0) catalyzed Stille-type coupling reaction with phenylmagnesium chloride failed due to elimination of palladium bromide and rearrangement to the phosphaacetylene Mes* CP (2). To prevent this undesired reaction, the monobromophosphaalkene Mes* PC(H)Br (6) was used. Although both isomers are known, a new method for the

Marcel van der Sluis; Angélique Klootwijk; Jan B. M. Wit; Friedrich Bickelhaupt; Nora Veldman; Anthony L. Spek; Peter W. Jolly

1997-01-01

192

Analysis of deformed palladium cathodes resulting from heavy water electrolysis  

Microsoft Academic Search

Earlier experiments suggested that large differences in heat release between the two sides of a palladium electrode coated with gold on one side and manganese oxide on the other cause observed electrode deformation with high-pressure Dâ gas loading in an electrolysis-like cell. Similar experiments were repeated using heavy water electrolysis. Palladium\\/titanium coatings on one side and gold coating on the

H. K. An; E. J. Jeong; J. H. Hong; Y. Lee

1995-01-01

193

Functional palladium metal films for plasmonic devices: an experimental proof  

NASA Astrophysics Data System (ADS)

Palladium-based, Inverted surface plasmon resonance substrates with functional surfaces are presented and characterized. The advantages of the use of palladium in lieu of other metals (most notably gold) are discussed and assayed experimentally. We demonstrate how the bare metal films can be functionalized by thiol chemistry or by adsorption of functional graphene sheets and how the features of the surfaces affect the performance of the substrate.

Zuccon, Sara; Zuppella, Paola; Cristofani, Michele; Silvestrini, Simone; Corso, Alain Jody; Maggini, Michele; Guglielmina Pelizzo, Maria

2014-05-01

194

Catalytic dechlorination of chlorophenols in water by palladium\\/iron  

Microsoft Academic Search

Three isomer chlorophenols, o-, m-, p-chlorophenol, were dechlorinated by palladium\\/iron powder in water through catalytic reduction. The dechlorinated reaction is believed to take place on the surface site of the catalyst in a pseudo-first-order reaction. The reduction product for all the three isomers is phenol. The dechlorination rate increases with increase of bulk loading of palladium due to the increase

Yihui Liu; Fenglin Yang; Po Lock Yue; Guohua Chen

2001-01-01

195

Synthesis and characterization of nitrides of iridium and palladiums  

SciTech Connect

We describe the synthesis of nitrides of iridium and palladium using the laser-heated diamond anvil cell. We have used the in situ techniques of x-ray powder diffraction and Raman scattering to characterize these compounds and have compared our experimental findings where possible to the results of first-principles theoretical calculations. We suggest that palladium nitride is isostructural with pyrite, while iridium nitride has a monoclinic symmetry and is isostructural with baddeleyite.

Crowhurst, Jonathan C.; Goncharov, Alexander F.; Sadigh, B.; Zaug, J.M.; Aberg, D.; Meng, Yue; Prakapenka, Vitali B. (LLNL); (CIW); (UC)

2008-08-14

196

The ternary system cerium-palladium-silicon  

NASA Astrophysics Data System (ADS)

Phase relations in the ternary system Ce-Pd-Si have been established for the isothermal section at 800 °C based on X-ray powder diffraction and EMPA techniques on about 130 alloys, which were prepared by arc-melting under argon or powder reaction sintering. Eighteen ternary compounds have been observed to participate in the phase equilibria at 800 °C. Atom order was determined by direct methods from X-ray single-crystal counter data for the crystal structures of ?8—Ce 3Pd 4Si 4 (U 3Ni 4Si 4-type, Immm; a=0.41618(1), b=0.42640(1), c=2.45744(7) nm), ?16—Ce 2Pd 14Si (own structure type, P4 /nmm; a=0.88832(2), c=0.69600(2) nm) and also for ?18—CePd 1-xSi x ( x=0.07; FeB-type, Pnma; a=0.74422(5), b=0.45548(3), c=0.58569(4) nm). Rietveld refinements established the atom arrangement in the structures of ?5—Ce 3PdSi 3 (Ba 3Al 2Ge 2-type, Immm; a=0.41207(1), b=0.43026(1), c=1.84069(4) nm) and ?13—Ce 3-xPd 20+xSi 6 (0? x?1, Co 20Al 3B 6-type, Fm3¯ m; a=1.21527(2) nm). The ternary compound Ce 2Pd 3Si 3 (structure-type Ce 2Rh 1.35Ge 4.65, Pmmn; a=0.42040(1), b=0.42247(1), c=1.72444(3) nm) was detected as a high-temperature compound, however, does not participate in the equilibria at 800 °C. Phase equilibria in Ce-Pd-Si are characterized by the absence of cerium solubility in palladium silicides. Mutual solubility among cerium silicides and cerium-palladium compounds are significant whereby random substitution of the almost equally sized atom species palladium and silicon is reflected in extended homogeneous regions at constant Ce-content such as for ?2—Ce(Pd xSi 1-x) 2 (AlB 2-derivative type), ? 6—Ce(Pd xSi 1-x) 2 (ThSi 2-type) and ?7—CePd 2-xSi 2+x. The crystal structures of compounds ?4—Ce ~8Pd ~46Si ~46, ?12—Ce ~29Pd ~49Si ~22, ?15—Ce ~22Pd ~67Si ~11, ?17—Ce ~5Pd ~77Si ~18 and ?18—CePd 1-xSi x ( x~0.1) are still unknown.

Lipatov, Alexey; Gribanov, Alexander; Grytsiv, Andriy; Rogl, Peter; Murashova, Elena; Seropegin, Yurii; Giester, Gerald; Kalmykov, Konstantin

2009-09-01

197

34 CFR 403.118 - Under what circumstances may the Secretary waive the distribution requirements for the...  

Code of Federal Regulations, 2013 CFR

34 Education 3 2013-07-01 2013-07-01 false ...requirements for the Postsecondary and Adult Vocational Education Programs? 403.118 Section 403.118 Education Regulations of the Offices of the Department...

2013-07-01

198

41 CFR 102-118.325 - Must I get approval for my agency's prepayment audit program?  

Code of Federal Regulations, 2010 CFR

...approval for my agency's prepayment audit program? 102-118.325 Section...approval for my agency's prepayment audit program? Yes, your agency must get approval for your prepayment audit program. The highest level budget...

2009-07-01

199

41 CFR 102-118.325 - Must I get approval for my agency's prepayment audit program?  

Code of Federal Regulations, 2010 CFR

...approval for my agency's prepayment audit program? 102-118.325 Section...approval for my agency's prepayment audit program? Yes, your agency must get approval for your prepayment audit program. The highest level budget...

2010-07-01

200

40 CFR 93.118 - Criteria and procedures: Motor vehicle emissions budget.  

Code of Federal Regulations, 2010 CFR

...Criteria and procedures: Motor vehicle emissions budget. 93.118 Section...Criteria and procedures: Motor vehicle emissions budget. (a) The transportation...must be consistent with the motor vehicle emissions budget(s) in the...

2010-07-01

201

40 CFR 93.118 - Criteria and procedures: Motor vehicle emissions budget.  

Code of Federal Regulations, 2010 CFR

...Criteria and procedures: Motor vehicle emissions budget. 93.118 Section...Criteria and procedures: Motor vehicle emissions budget. (a) The transportation...must be consistent with the motor vehicle emissions budget(s) in the...

2009-07-01

202

Electrocatalysts having platium monolayers on palladium, palladium alloy, and gold alloy core-shell nanoparticles, and uses thereof  

DOEpatents

The invention relates to platinum-coated particles useful as fuel cell electrocatalysts. The particles are composed of a noble metal or metal alloy core at least partially encapsulated by an atomically thin surface layer of platinum atoms. The invention particularly relates to such particles having a palladium, palladium alloy, gold alloy, or rhenium alloy core encapsulated by an atomic monolayer of platinum. In other embodiments, the invention relates to fuel cells containing these electrocatalysts and methods for generating electrical energy therefrom.

Adzic, Radoslav (Setauket, NY); Mo, Yibo (Naperville, IL); Vukmirovic, Miomir (Port Jefferson Station, NY); Zhang, Junliang (Rochester, NY)

2010-12-21

203

MEMS-based thin palladium membrane microreactors  

NASA Astrophysics Data System (ADS)

We microfabricated a MEMS (Micro Electro Mechanical System) based thin palladium (Pd) membrane microreactor with oxidized porous silicon (PS) support. The membranes were characterized by permeation experiments with hydrogen, nitrogen, and helium at temperature ranging from 200°C to 250°C. The hydrogen flux through the Pd membrane with a thickness of 340 nm was 0.112 mol m -2 s -1 at 250°C and a partial pressure difference of 110 kPa. H II/N II and H II/He selectivity was about 46 and 10 at 250°C, respectively. The thermal isolation of the Pd membrane, which was heated by an integrated microheater, was realized by using the oxidized PS. We also carried out the hydrogenation of 1-butene at 250°C using the developed microreactor. The results of long term test of about three months suggest that Pd membrane microreactor has a potential to be used in practical applications.

Ye, S.-Y.; Tanaka, S.; Esashi, M.; Hamakawa, S.; Hanaoka, T.; Mizukami, F.

2006-01-01

204

Electrochemical Synthesis and Characterization of Palladium Nanostructures  

NASA Astrophysics Data System (ADS)

Palladium (Pd) is a good candidate material for hydrogen gas sensing at room temperature due to its high affinity to hydrogen. Pd in the form of nanostructures has demonstrated better performance in its gas sensing property as compared to that in the form of bulk metal because of its large surface area to volume ratio. In this work, various Pd nanostructures were synthesized via electrochemical route. Pd in the form of nanowires can be produced directly via template-assisted electrodeposition while Pd nanotubes were synthesized by galvanic displacement with morphology and composition governed by electrolyte temperature and reaction time. Using similar electrodeposition conditions, Pd in the form of nanoparticles were electrochemically decorated on the surfaces of ZnO rods and Si nanowires arrays. Growth study on various Pd nanostructures produced is presented here, using microscopy, diffraction and probe-based techniques for microstructural, morphological and chemical characterizations.

Ilias, S. H.; Kok, K. Y.; Ng, I. K.; Saidin, N. U.

2013-04-01

205

Electronic Transitions of Palladium and Vanadium Dimer  

NASA Astrophysics Data System (ADS)

The laser induced fluorescence (LIF) spectrum of palladium dimer (Pd_{2}) in the visible region between 480 and 700 nm has been studied. Five vibrational bands were recorded and analyzed; they are assigned to a ^{3} ? _{g} - X^{3} ? _{u} ^{+} system. The vibrational frequency of the ground X^{3} ? _{u} ^{+} state has been determined to be 211.4 cm^{-1}. This is the first experimental observation of the LIF spectrum of Pd_{2}. In addition, the LIF spectrum of vanadium dimer (V_{2}) has also been studied; several new transition band systems were observed in the wavelength between 480 and 530 nm. The analysis of the spectra recorded for these two molecules will be presented.

Qian, Yue; Ng, Y. W.; Cheung, A. S.-C.

2013-06-01

206

Hydrogen concentration depth profiles and superconductivity in the palladium copper hydride system  

SciTech Connect

A sample configuration has been devised to study palladium copper hydride alloys with respect to hydrogen concentration depth profiles; and superconducting parameters. Superconducting palladium copper hydride samples, which displayed transition temperatures in agreement with data measured by Stritzker, were obtained. Thin palladium copper alloy films, which were formed on top of palladium substrate foils by ion beam and solid state techniques, were hydrogenized using electrolysis, hydrogen gas pressure charging and hydrogen ion implantation. The thin palladium copper surface films proved permeable to hydrogen, which was present in higher near surface concentrations as expected by literature. Correlation of critical superconducting transition temperature data to hydrogen concentration depth profiles was obtained. In situ measurements displayed a transition of a palladium copper hydride sample from the normal metallic to the superconducting state upon annealing treatment. Alloy structure, a parameter so far neglected by literature was determined to be significant for the formation of superconducting palladium hydride as well as palladium copper hydride.

Leiberich, A.

1983-01-01

207

Analysis of Central Events in the Interactions of Relativistic Heavy Ions with Emulsion Nuclei at 118.4 GeV  

SciTech Connect

Data on the multiplicity of the secondary produced particles in the central events from the interactions of 32S with AgBr nuclei at 118.4 GeV. A different selection criteria of the central collision in heavy ion interactions was investigated. The multiplicity distributions of the different produced shower particles (mainly pions) in the central events for each criteria was studied. The multiplicity distributions of the target fragments emitted in the central events was fitted by a Gaussian distribution. The target analysis of the experimental data shows agreement with the limiting fragmentation hypothesis.

EL-Falaky, E. [Physics Department, Faculty of Education, Suez Canal University, El-Suez (Egypt)

2007-02-14

208

Coverage of palladium by silicon oxide during reduction in H 2 and complete oxidation of methane  

Microsoft Academic Search

The interaction between silica and palladium following complete oxidation of methane or following reduction in H2 was investigated on a polycrystalline palladium foil and on supported Pd\\/SiO2 catalysts. During methane oxidation, oxidized silicon covered the palladium oxide surface as observed by TEM on Pd\\/SiO2 catalysts and by XPS on palladium foil. On the Pd foil, the source of silica was

Guanghui Zhu; Ken-ichiro Fujimoto; Dmitri Yu. Zemlyanov; Abhaya K. Datye; Fabio H. Ribeiro

2004-01-01

209

Investigations of photo-induced decomposition of palladium acetate for electroless copper plating  

Microsoft Academic Search

Photo-induced decomposition of palladium acetate films has been performed by using argon and xenon excimer vacuum ultraviolet (VUV) sources that emit radiation peaking at wavelengths of 126 and 172 nm, respectively. VUV irradiation of a substrate treated with palladium acetate results in the formation of palladium, which acts as a catalyst for subsequent copper plating by means of an electroless

Jun-Ying Zhang; Ian W. Boyd

1998-01-01

210

Preliminary Design of Fusion Reactor Fuel Cleanup System by Palladium Alloy Membrane Method.  

National Technical Information Service (NTIS)

A design of palladium diffuser and Fuel Cleanup System (FCU) for D-T fusion reactor is proposed. Feasibility of palladium alloy membrane method is discussed based on the early studies by the authors. Operating conditions of the palladium diffuser are dete...

H. Yoshida S. Konishi Y. Naruse

1981-01-01

211

Photochemical formation of palladium patterns on surface-modified polyimide resin  

Microsoft Academic Search

A simplified method for forming a palladium circuit pattern on polyimide resin substrate was proposed. The carboxyl group, as a cation exchange group, was formed on the polyimide resin surface by a potassium hydroxide treatment. Palladium(II) ion was then adsorbed onto the surface modified polyimide resin by ion exchange. Ultraviolet irradiation of this palladium(II) ion absorbed resin with sodium formate

M. Seita; H. Nawafune; T. Nishioka; S. Mizumoto; T. Kanai

2002-01-01

212

Comparison of palladium thin films used in a transmission based optical fibre hydrogen sensor  

Microsoft Academic Search

Results are presented of a comparison between two palladium films of different thicknesses used as the sensing element in a transmission based optical fiber hydrogen sensor. The palladium films, 16nm and 26nm thick, were deposited onto glass substrates using thermal vacuum evaporation. The absorption and desorption of hydrogen causes the optical properties of palladium to change depending on the concentration

K. Gleeson; E. Lewis

2008-01-01

213

Fabrication and Characterization of a Hydrogen Sensor Based on Palladium Nanowires  

Microsoft Academic Search

A hydrogen sensor based on an array of palladium nanowires has been realized starting from a silicon substrate coated with a Si3N4 where an interdigitated electrode pattern has been fabricated using photolithography. Saturated palladium solution has been prepared and array of palladium nanowires has been formed applying at the electrodes a voltage signal. As grown Pd nanowires are conductive and

V. La Ferrara; B. Alfano; E. Massera; I. Nasti; G. Di Francia

2007-01-01

214

Dynamics of palladium on nanocarbon in the direct synthesis of H2O2.  

PubMed

This work aims to clarify the nanostructural transformation accompanying the loss of activity and selectivity for the hydrogen peroxide synthesis of palladium and gold-palladium nanoparticles supported on N-functionalized carbon nanotubes. High-resolution X-ray photoemission spectroscopy (XPS) allows the discrimination of metallic palladium, electronically modified metallic palladium hosting impurities, and cationic palladium. This is paralleled by the morphological heterogeneity observed by high-resolution TEM, in which nanoparticles with an average size of 2 nm coexisted with very small palladium clusters. The morphological distribution of palladium is modified after reaction through sintering and dissolution/redeposition pathways. The loss of selectivity is correlated to the extent to which these processes occur as a result of the instability of the particle at the carbon surface. We assign beneficial activity in the selective hydrogenation of oxygen to palladium clusters with a modified electronic structure compared with palladium metal or palladium oxides. These beneficial species are formed and stabilized on carbons modified with nitrogen atoms in substitutional positions. The formation of larger metallic palladium particles not only reduces the number of active sites for the synthesis, but also enhances the activity for deep hydrogenation to water. The structural instability of the active species is thus detrimental in a dual way. Minimizing the chance of sintering of palladium clusters by all means is thus the key to better performing catalysts. PMID:24133011

Arrigo, Rosa; Schuster, Manfred E; Abate, Salvatore; Wrabetz, Sabine; Amakawa, Kazuhiko; Teschner, Detre; Freni, Maria; Centi, Gabriele; Perathoner, Siglinda; Hävecker, Michael; Schlögl, Robert

2014-01-01

215

Highly sensitive hydrogen sensors using palladium coated fiber optics with exposed cores and evanescent field interactions  

Microsoft Academic Search

A novel fiber optic hydrogen sensor which is constructed by depositing palladium over an exposed core region of a multimode fiber is reported. The sensing mechanism is based on evanescent field interaction with the palladium coating. Since the length, thickness, and composition of the palladium patch can be controlled independently of each other, it is possible to increase the speed

Massood Tabib-Azar; Boonsong Sutapun; Rose Petrick; Alex Kazemi

1999-01-01

216

41 CFR 102-118.230 - What if my agency creates or eliminates a field office approved to prepare transportation documents?  

Code of Federal Regulations, 2013 CFR

...eliminates a field office approved to prepare transportation documents? 102-118.230 Section 102-118...Continued) FEDERAL MANAGEMENT REGULATION TRANSPORTATION 118-TRANSPORTATION PAYMENT AND AUDIT Use of Government...

2013-07-01

217

Recovery of Elemental Palladium by Shewanella putrefaciens  

NASA Astrophysics Data System (ADS)

Microbial reduction of metals plays an important role in environmental behavior and provides a technique for the recovery of metals from industrial wastewater. Recently, demand for platinum group metals (PGMs) increases by their catalytic properties. The extreme rarity of PGMs have led to a growing interest in their recovery. Palladium, one of PGMs, has different oxidation states of Pd(II) and Pd(0). The oxidized form of Pd(II) is soluble, while the reduced form of Pd(0) is insoluble. In this study, microbial reduction of palladium by Fe(III)- reducing bacterium, Shewanella putrefaceins was conducted. This bacterium is known to be capable of reducing metals, such as Mn(IV), U(VI), or Tc(VII) with organic C or H2 as an electron donor. In order to investigate the potential of S. putrefaciens to reduce Pd(II) in solution, resting cells or heat-killed cells were suspended under anaerobic conditions with lactate or H2 as an electron donor. The cells of S. putrefaciens (NBRC3908) were grown in aerobic medium, harvested by centrifugation, and then washed with 25 mmol/dm3 HEPES and 100 mmol/dm3 NaCl (HEPES-NaCl) solution (pH 7.0). The heat-killed cells were autoclaved for 20 min at 121 degrees C. The cell suspension (21.5 mg in dry weight) was resuspended in the HEPES-NaCl solution which contained 1.0 mmol/dm3 Na2PdCl4 (Wako Pure chemical Industries, Ltd). The suspensions were bubbled with N2 for 15 min before 10 mmol/dm3 lactate or 4.8 v/v% H2 was added. The suspensions were then incubated at 30 degrees C. Redox potential (Eh) and pH of the solutions were measured in an inert glove box with Ar gas. Concentration of Pd(II) was measured by Inductively Coupled Plasma Atomic Emission Spectrometer (ICP-AES). Deposited Pd and cells were analyzed by X-ray powder diffraction (XRD) and Scanning Electron Microscope (SEM) with Energy-Dispersive Spectroscopy (EDS). Approximately 86% of Pd(II) of the initial concentration was removed from solution by the resting cells within 24 h when lactate was used as an electron donor. A black precipitates were observed in the solution, that was confirmed as Pd(0) by XRD analysis. SEM and EDS analyses identified that Pd bearing precipitates were present on and/or in the cells. The size of the precipitates associated with cells was approximately 100 nm in diameter. Approximately 23% of Pd(II) was removed by the heat-killed cells within 24 h. The precipitates between 200 and 300 nm in diameter were observed to be associated with the heat-killed cells by SEM and EDS analyses. No removal of Pd(II) was obtained without cells. On the contrary, complete removal of Pd(II) was occurred within 4 h after exposure of the resting cells to Pd(II) solution when H2 was used as an electron donor. Approximately 88 and 80% of Pd(II) was removed within 4 h with the heat-killed cells and without cells, respectively. The measured Eh and pH values were plotted in the Eh-pH diagram calculated for Pd-Cl-H2O system indicated that chemical conditions in the solutions were saturated with respect to Pd(0) at 24 or 4 h of incubation regardless the electron donor. These findings indicate that S. putrefaciens is capable to enhance the precipitation of palladium from solution by reducing Pd(II) to Pd(0) with lactate or H2 as an electron donor.

Akasaka, S.; Xia, X.; Sawada, K.; Enokida, Y.; Yamamoto, I.; Ohnuki, T.

2006-12-01

218

Sputtering induced surface composition changes in copper-palladium alloys  

NASA Astrophysics Data System (ADS)

It has been observed that, in general, surface composition is different from bulk composition in multicomponent materials as a result of ion beam sputtering. This compositional difference arises from factors like preferential sputtering, radiation induced concentration gradients and the knock-in effect. In the present work, changes in the surface composition of copper-palladium alloys, brought about by argon ion sputtering, have been studied using Auger electron spectroscopy. Argon ion energy has been varied from 500 eV to 5 keV. Enrichment of palladium has been observed in the sputter-altered layer. The palladium enrichment at the surface has been found to be higher for 500 eV argon ion sputtering compared with argon ion sputtering at higher energies. Above 500 eV, the surface composition has been observed to remain the same irrespective of the sputter ion energy for each alloy composition. The bulk composition ratio of palladium to copper has been found to be linearly related to the sputter altered surface composition ratio of palladium to copper. These results are discussed on the basis of recent theories of alloy sputtering.

Sundararaman, M.; Sharma, S. K.; Kumar, Lalit; Krishnan, P.

219

The preparation of palladium for cold fusion experiments  

NASA Astrophysics Data System (ADS)

Techniques have been established to prepare palladium specimens for cold fusion experiments using an ultra-high-vacuum, allmetal, high-temperature furnace to melt palladium metal in high purity alumina molds having a test tube shape. To date 6-mm and 15-mm cylinders have been fabricated, the latter being used to fabricate a sphere 12.5-mm in diameter. Techniques and facilities used for palladium-hydrogen isotope pressure-volume-temperature measurements1-4 have been used to anneal these palladium specimens after machining and, in some cases, to charge these specimens with deuterium to PdD0.63 stoichiometry prior to their use in electrochemical cells. The modeling of palladium-hydrogen isotope pressure-composition-temperature curves is described wherein existing data5,6 is used to derive models that accurately describe the existing data and that extrapolate to high compositions. Experiments for reacting6LiD with Pd rods at 700°C to 800°C, in an attempt to precharge6Li into the Pd rods, are being prepared.

Powell, G. L.; Bullock, J. S.; Hallman, R. L.; Horton, P. J.; Hutchinson, D. P.

1990-09-01

220

Modulation of CdSe fluorescence using palladium nanoparticles  

NASA Astrophysics Data System (ADS)

The increasing demand for clean, efficient energy has strongly influenced the direction of nanoscale research. One of the most promising areas of solar energy production lies with cadmium selenide quantum dots (CdSe QDs). As a means to improve the efficiency of solar energy conversion in QDs, metal nanoparticles have been examined. It has been shown that in certain systems the presence of these metal nanoparticles increase electron - hole charge separation thus providing extended times for electron harvesting. Most of the systems currently explored utilize gold nanoparticles, which is unsurprising due to the vast amount of synthetic methods for these particles and their plasmonic effects on the QDs. We seek to further examine these unique metal nanoparticle -quantum dot interactions through the study of CdSe QD - palladium nanoparticle systems. We employ both steady-state and time resolved ensemble fluorescence spectroscopy to observe the effects of increasing palladium nanoparticle concentrations on both the fluorescence intensity and lifetime of various CdSe QDs. We find that decreasing separation distance between the particles through increasing palladium concentration, leads to a stronger interaction between the particles. We find expected fluorescence quenching of the QDs at higher concentrations of palladium. At low palladium concentrations however we observe a unique fluorescence enhancement of the QDs. We use this data to explore the relative contributions of energy and electron transfer between the particles and determine the conditions under which the maximum effects of these interactions are observed.

Major, Kevin J.; Jones, Marcus

2011-09-01

221

Development and Bioorthogonal Activation of Palladium-Labile Prodrugs of Gemcitabine  

PubMed Central

Bioorthogonal chemistry has become one of the main driving forces in current chemical biology, inspiring the search for novel biocompatible chemospecific reactions for the past decade. Alongside the well-established labeling strategies that originated the bioorthogonal paradigm, we have recently proposed the use of heterogeneous palladium chemistry and bioorthogonal Pd0-labile prodrugs to develop spatially targeted therapies. Herein, we report the generation of biologically inert precursors of cytotoxic gemcitabine by introducing Pd0-cleavable groups in positions that are mechanistically relevant for gemcitabine’s pharmacological activity. Cell viability studies in pancreatic cancer cells showed that carbamate functionalization of the 4-amino group of gemcitabine significantly reduced (>23-fold) the prodrugs’ cytotoxicity. The N-propargyloxycarbonyl (N-Poc) promoiety displayed the highest sensitivity to heterogeneous palladium catalysis under biocompatible conditions, with a reaction half-life of less than 6 h. Zebrafish studies with allyl, propargyl, and benzyl carbamate-protected rhodamines confirmed N-Poc as the most suitable masking group for implementing in vivo bioorthogonal organometallic chemistry.

2014-01-01

222

Development and bioorthogonal activation of palladium-labile prodrugs of gemcitabine.  

PubMed

Bioorthogonal chemistry has become one of the main driving forces in current chemical biology, inspiring the search for novel biocompatible chemospecific reactions for the past decade. Alongside the well-established labeling strategies that originated the bioorthogonal paradigm, we have recently proposed the use of heterogeneous palladium chemistry and bioorthogonal Pd(0)-labile prodrugs to develop spatially targeted therapies. Herein, we report the generation of biologically inert precursors of cytotoxic gemcitabine by introducing Pd(0)-cleavable groups in positions that are mechanistically relevant for gemcitabine's pharmacological activity. Cell viability studies in pancreatic cancer cells showed that carbamate functionalization of the 4-amino group of gemcitabine significantly reduced (>23-fold) the prodrugs' cytotoxicity. The N-propargyloxycarbonyl (N-Poc) promoiety displayed the highest sensitivity to heterogeneous palladium catalysis under biocompatible conditions, with a reaction half-life of less than 6 h. Zebrafish studies with allyl, propargyl, and benzyl carbamate-protected rhodamines confirmed N-Poc as the most suitable masking group for implementing in vivo bioorthogonal organometallic chemistry. PMID:24867590

Weiss, Jason T; Dawson, John C; Fraser, Craig; Rybski, Witold; Torres-Sánchez, Carmen; Bradley, Mark; Patton, E Elizabeth; Carragher, Neil O; Unciti-Broceta, Asier

2014-06-26

223

Local magnetism in palladium bionanomaterials probed by muon spectroscopy.  

PubMed

Palladium bionanomaterial was manufactured using the sulfate-reducing bacterium, Desulfovibrio desulfuricansm, to reduce soluble Pd(II) ions to cell-bound Pd(0) in the presence of hydrogen. The biomaterial was examined using a Superconducting Quantum Interference Device (SQUID) to measure bulk magnetisation and by Muon Spin Rotation Spectroscopy (µSR) which is uniquely able to probe the local magnetic environment inside the sample. Results showed behaviour attributable to interaction of muons both with palladium electrons and the nuclei of hydrogen trapped in the particles during manufacture. Electronic magnetism, also suggested by SQUID, is not characteristic of bulk palladium and is consistent with the presence of nanoparticles previously seen in electron micrographs. We show the first use of ?SR as a tool to probe the internal magnetic environment of a biologically-derived nanocatalyst material. PMID:21331587

Creamer, Neil J; Mikheenko, Iryna P; Johnson, Clive; Cottrell, Stephen P; Macaskie, Lynne E

2011-05-01

224

Leaching kinetics of platinum and palladium from spent automotive catalysts  

SciTech Connect

This report describes a study into the teaching kinetics of selected metals from automotive catalysts. Empirical rate expressions for both platinum and palladium were obtained from mass balances and concentration time data in a packed bed reactor using different (HCL):(HNO/sub 3/) leaching solution concentration ratios. The spent catalysts used in this study (minus 60 plus 70 mesh to minus 120 plus 140 mesh) were analyzed to be 3,791 parts per million (ppm) platinum and 1,306 ppm palladium. High initial rates for both platinum and palladium were obtained for the early stages of leaching and were followed by rapid decay up to about 110 minutes and 50 minutes, respectively.

Tyson, D.R.; Bautista, R.G.

1987-01-01

225

Instability of diatomic deuterium in fcc palladium  

NASA Astrophysics Data System (ADS)

To clarify some of the solid-state aspects of cold fusion in deuterated transition metal electrodes, we have carried out first-principles self-consistent total energy calculations for various configurations of atomic and diatomic deuterium inside fcc palladium. We find that the stability of the Pd+D system is controlled by the relative position of the deuterium-induced antibonding level with respect to the Fermi energy. The equilibrium D-D distance in dense PdD ? up to ?=3 is found to be much larger than the free space value. The calculated Born-Oppenheimer energy surface of diatomic D2 in crystalline palladiuim is shown to have but metastable local minima whose internuclear separation is at least 0.2 Å larger than that of the isolated D2 molecule. We conclude that D2 in crystalline Pd will have a substantially lower tunneling probability than hitherto thought and that explanation for fusion mechanisms should be sought elsewhere.

Wei, Su-Huai; Zunger, Alex

1990-12-01

226

Superlattices of platinum and palladium nanoparticles  

SciTech Connect

The authors have used a nonionic inverse micelle synthesis technique to form nanoclusters of platinum and palladium. These nanoclusters can be rendered hydrophobic or hydrophilic by the appropriate choice of capping ligand. Unlike Au nanoclusters, Pt nanoclusters show great stability with thiol ligands in aqueous media. Alkane thiols, with alkane chains ranging from C{sub 6} to C{sub 18} were used as hydrophobic ligands, and with some of these they were able to form 2-D and/or 3-D superlattices of Pt nanoclusters as small as 2.7 nm in diameter. Image processing techniques were developed to reliably extract from transmission electron micrographs (TEMs) the particle size distribution, and information about the superlattice domains and their boundaries. The latter permits one to compute the intradomain vector pair correlation function of the particle centers, from which they can accurately determine the lattice spacing and the coherent domain size. From these data the gap between the particles in the coherent domains can be determined as a function of the thiol chain length. It is found that as the thiol chain length increases, the gaps between particles within superlattice domains increases, but more slowly than one might expect, possibly indicating thiol chain interdigitation.

MARTIN,JAMES E.; WILCOXON,JESS P.; ODINEK,JUDY G.; PROVENCIO,PAULA P.

2000-04-06

227

Deuterium occupation of tetrahedral sites in palladium  

NASA Astrophysics Data System (ADS)

The long-standing controversy over the occupation by hydrogen of tetrahedral interstices in palladium has been addressed experimentally and theoretically. Using the highest resolution neutron powder diffractometer available, diffraction profiles were recorded from single-phase samples obtained by loading Pd with deuterium in situ at 310°C , at D2 pressures up to 90 bar. Rietveld profile analysis showed that a model including tetrahedral occupancy was necessary to properly fit the experimental diffraction profiles. The maximum absolute tetrahedral occupancy was found at a deuterium-to-metal atomic ratio of 0.6, where about one-third of all D atoms were in tetrahedral sites. At the lowest and highest D concentration, the tetrahedral fraction approached zero. The energy of formation was calculated, based on density-functional theory, for numerous configurations of octahedral and tetrahedral interstitials in a supercell, which modeled stoichiometries Pd8Hn such that n=1,2,…8 . For Pd8H3 , the minimum formation energy was found with 1-2 tetrahedral atoms. For all other stoichiometries, the minimum formation energy was 0-1 tetrahedral atoms. Thus, the calculations are in excellent qualitative agreement with experiment and support the reality of tetrahedral occupancy.

McLennan, K. G.; Gray, E. Maca.; Dobson, J. F.

2008-07-01

228

Genome Characterisation of Enteroviruses 117 and 118: A New Group within Human Enterovirus Species C  

PubMed Central

The more than 120 genotypes of human enteroviruses (HEVs) reflect a wide range of evolutionary divergence, and there are 23 currently classified as human enterovirus C species (HEV-C). Two new HEV-C (EV-C117 and EV-C118) were identified in the Community-Acquired Pneumonia Pediatric Research Initiative (CAP-PRI) study, and the present paper describes the characterisation of the complete genome of one EV-C117 strain (LIT22) and two EV-C118 (ISR38 and ISR10) strains. The EV-C117 and EV-C118 5?UTR sequences were related to those of EV-C104, EV-C105 and EV-C109, and were slightly shorter than those of other HEV A-D species. Similarity plot analyses showed that EV-C117 and EV-C118 have a P1 region that is highly divergent from that of the other HEV-C, and phylogenetic analyses highly supported a monophyletic group consisting of EV-C117, EV-C118, EV-C104, EV-C105 and EV-C109 strains. Phylogenetic, Simplot and Bootscan analyses indicated that recombination was not the main mechanism of EV-C117 and EV-C118 evolution, thus strengthening the hypothesis of the monophyletic origin of the coding regions, as in the case of other HEV-C. Phylogenetic analysis also revealed the emergence of a new group within HEV-C that is divided into two subgroups. Nucleotide and amino acid identity in VP1 sequences have been established as useful criteria for assigning new HEV types, but analysis of the complete P1 region improves resolution.

Scala, Alessia; Greenberg, David; Usonis, Vytautas; Principi, Nicola; Baldanti, Fausto; Esposito, Susanna

2013-01-01

229

Genome characterisation of enteroviruses 117 and 118: a new group within human enterovirus species C.  

PubMed

The more than 120 genotypes of human enteroviruses (HEVs) reflect a wide range of evolutionary divergence, and there are 23 currently classified as human enterovirus C species (HEV-C). Two new HEV-C (EV-C117 and EV-C118) were identified in the Community-Acquired Pneumonia Pediatric Research Initiative (CAP-PRI) study, and the present paper describes the characterisation of the complete genome of one EV-C117 strain (LIT22) and two EV-C118 (ISR38 and ISR10) strains. The EV-C117 and EV-C118 5'UTR sequences were related to those of EV-C104, EV-C105 and EV-C109, and were slightly shorter than those of other HEV A-D species. Similarity plot analyses showed that EV-C117 and EV-C118 have a P1 region that is highly divergent from that of the other HEV-C, and phylogenetic analyses highly supported a monophyletic group consisting of EV-C117, EV-C118, EV-C104, EV-C105 and EV-C109 strains. Phylogenetic, Simplot and Bootscan analyses indicated that recombination was not the main mechanism of EV-C117 and EV-C118 evolution, thus strengthening the hypothesis of the monophyletic origin of the coding regions, as in the case of other HEV-C. Phylogenetic analysis also revealed the emergence of a new group within HEV-C that is divided into two subgroups. Nucleotide and amino acid identity in VP1 sequences have been established as useful criteria for assigning new HEV types, but analysis of the complete P1 region improves resolution. PMID:23565264

Piralla, Antonio; Daleno, Cristina; Scala, Alessia; Greenberg, David; Usonis, Vytautas; Principi, Nicola; Baldanti, Fausto; Esposito, Susanna

2013-01-01

230

Tank 241-TX-118 vapor sampling and analysis tank characterization report  

SciTech Connect

Tank 241-TX-118 headspace gas and vapor samples were collected and analyzed to help determine the potential risks to tank farm workers due to fugitive emissions from the tank. The drivers and objectives of waste tank headspace sampling and analysis are discussed in {open_quotes}Program Plan for the Resolution of Tank Vapor Issues.{close_quotes} Tank 241-TX-118 was vapor sampled in accordance with {open_quotes}Data Quality Objectives for Generic In-Tank Health and Safety Issue Resolution.{close_quotes}

Huckaby, J.L.

1995-05-31

231

SPECTROPHOTOMETRIC DETERMINATION OF COPPER AND PALLADIUM USING A NEW REAGENT  

Microsoft Academic Search

Highly sensitive spectrophotometric methods for determination of copper and palladium by a new synthesized chromogenic reagent N-dodecyl-N?-(sodium p-amino-benzenesulfonate)-thiourea (DOPT) were developed. In the presence of CTMAB and NaAc-HAc buffer solution, under the optimum conditions for color reaction of copper and palladium with DOPT, their molar absorptivities are ?300.4 nm = 1.56 × 10 l mol cm at 300.4 nm for copper and ?296.0 nm = 7.41

Donglan Ma; Fengling Cui; Dongsheng Xia; Yulu Wang

2002-01-01

232

Origin of palladium black by an infrared spectroscopic method  

SciTech Connect

Metal blacks are used as catalysts in a number of organic synthesis processes. Using the method of matrix insulation of blacks obtained from organometallic compounds in the inert atmosphere the IR spectra have been recorded for carbon monoxide adsorbed on actual palladium blacks. The controllable mild conditions for reduction of the initial complex by hydrazine hydrate provide a means of separating the intermediate states of this process. By discontinuing at various stages the reduction of the organometallic complex being investigated the authors have obtained IR spectra of carbon monoxide characterizing the stages of forming the metallic palladium black.

Vozdvizhenskii, V.F.; Levintova, T.D.; Sokol'skii, D.V.

1987-03-01

233

Structure of Palladium Nanoclusters for Hydrogen Gas Sensors  

SciTech Connect

Palladium nanoclusters produced by inert gas aggregation/magnetron sputtering are used as building blocks for the construction of nano electronic devices with large surface to volume ratios that can be used as sensitive hydrogen gas sensors in fuel cells and in petrochemical plants. X-ray diffraction (XRD), extended X-ray absorption fine structure (EXAFS), and high resolution transmission electron microscopy (HRTEM) have been used to characterize the structure, lattice constant, particle diameter and oxide thickness of the palladium nanoclusters in order to understand the operation of these sensors. Grazing incidence XRD (GIXRD) of heat treated Pd clusters has shown that the palladanite structure forms at elevated temperatures.

Stevens, K.J.; Ingham, B.; Toney, M.F.; Brown, S.A.; Lassesson, A.; /SLAC, SSRL /Canterbury U.

2009-05-11

234

Platinum-monolayer Electrocatalysts: Palladium Interlayer on IrCo Alloy Core Improves Activity in Oxygen-reduction Reaction  

SciTech Connect

We describe the synthesis and electrocatalytic properties of a new low-Pt electrocatalyst consisting of an IrCo core, a Pd interlayer, and a surface Pt monolayer, emphasizing the interlayer's role in improving electrocatalytic activity for the oxygen-reduction reaction on Pt in HClO{sub 4} solution. We prepared the IrCo alloys by decomposing, at 800 C, hexacyanometalate, KCoIr(CN){sub 6}, adsorbed on the carbon surfaces. The synthesis of Ir{sub 3}Co/C involved heating a mix of metal salts and carbon in hydrogen at 500 C. Thereafter, we placed a palladium and/or platinum monolayer on them via the galvanic displacement of an underpotentially deposited copper monolayer. The electrocatalysts were characterized using structural- and electrochemical-techniques. For PtML/PdML/IrCo/C, we observed a Pt mass activity of 1.18 A/mg{sub (Pt)} and the platinum-group-metals mass of 0.16 A/mg{sub (Pt, Pd, Ir)}. In comparison, without a Pd interlayer, i.e., Pt{sub ML}/IrCo/C, the activities of 0.15 A/mg{sub (Pt)} and 0.036 A/mg{sub (Pt, Pd, Ir)} were considerably lower. We consider that the palladium interlayer plays an essential role in achieving high catalytic activity by adjusting the electronic interaction of the platinum monolayer with the IrCo core, so that it accelerates the kinetics of adsorption and desorption of the intermediates of oxygen reduction. A similar trend was observed for Pt{sub ML}/Pd{sub ML} and Pt{sub ML} deposited on Ir{sub 3}Co/C alloy core. We used density functional theory to interpret the observed phenomena.

Gong, K.; Chen, W.-F.; Sasaki, K.; Su, D.; Vukmirovic, M.B.; Zhou, W.; Izzo, E.L.; Perez-Acosta, C.; Hirunsit, P.; Balbuena, P.B.; Adzic, R.R.

2010-11-15

235

Hydrogenation of nitroaromatics by polymer-anchored bimetallic palladium-ruthenium and palladium-platinum catalysts under mild conditions  

Microsoft Academic Search

Polymer-achored monometallic palladium catalyst PVP-PdCl2 (PVP = poly(N-vinyl-2-pyrrolidone)) exhibits very high activity for the hydrogenation of p-chloronitrobenzene (CNB) to aniline (AN) in the presence of base at 65°C and atmospheric pressure. In this case, the substrate is rapidly hydrodechlorinated to nitrobenzene (NB) which is then reduced to AN. Using the polymer-anchored bimetallic palladium-ruthenium catalyst, PVP-PdCl2-RuCl3, and in the presence of

Zhengkun Yu; Shijian Liao; Yun Xu; Bin Yang; Daorong Yu

1997-01-01

236

A novel thiazolidinedione derivative TD118 showing selective algicidal effects for red tide control.  

PubMed

Thiazolidinedione (TD) derivatives have been found to have an algicidal effect on harmful algal bloom microalgae. In this study, 75 TD derivatives were synthesized and analyzed for algicidal activity. Among these synthetic TDs, 18 TD derivatives showed specific algicidal activity on two strains belonging to the classes Raphidophyceae (Chattonella marina and Heterosigma akashiwo) and Dinophyceae (Cochlodinium polykrikoides). Two strains belonging to Bacillariophyceae (Navicula pelliculosa and Phaeodactylum EPV), one strain belonging to Dinophyceae (Amphidinium sp.), and a Eustigmatophycean microalga (Nannochloropsis oculata) showed less sensitivity to the TD derivatives than the other two phyla. The most reactive TD derivative, compound 2 (TD118), was selected and tested for morphological and physiological changes. TD118 effectively damaged the cell membrane of C. marina, H. akashiwo and C. polykrikoides. The O? evolution and photosystem II efficiency (F(v)/F(m)) of C. marina, H. akashiwo and C. polykrikoides were also severely reduced by TD118 treatment. Amphidinium sp., N. pelliculosa, Phaeodactylum EPV and N. oculata showed less reduction of O? evolution and the F(v)/F(m) by TD118. These results imply that the species-specific TD structure relationship may be due to structural and/or physiological differences among microalgal species. PMID:24374490

Wu, Ying; Lee, Yew; Jung, Seul-Gi; Kim, Minju; Eom, Chi-Yong; Kim, Si Wouk; Cho, Hoon; Jin, Eonseon

2014-05-01

237

CII Honeywell Bull, Level 64 DPS7, COBOL-74 V-55.118.  

National Technical Information Service (NTIS)

This Validation Summary Report (VSR) for the CII Honeywell Bull, COBOL V-55.118 running under the provides a consolidated summary of the results obtained from the validation of the subject compiler against the 1974 COBOL Standard (X3.23-1974/FIPS PUB 21-1...

1982-01-01

238

Cleanup Verification Package for the 118-F-7, 100-F Miscellaneous Hardware Storage Vault  

SciTech Connect

This cleanup verification package documents completion of remedial action for the 118-F-7, 100-F Miscellaneous Hardware Storage Vault. The site consisted of an inactive solid waste storage vault used for temporary storage of slightly contaminated reactor parts that could be recovered and reused for the 100-F Area reactor operations.

M. J. Appel

2006-11-02

239

Preliminary tank characterization report for single-shell tank 241-TX-118: best-basis inventory  

SciTech Connect

An effort is underway to provide waste inventory estimates that will serve as standard characterization source terms for the various waste management activities. As part of this effort, an evaluation of available information for single-shell tank 241-TX-118 was performed, and a best-basis inventory was established. This work follows the methodology that was established by the standard inventory task.

Jo, J.

1997-09-02

240

Cleanup Verification Package for the 118-C-1, 105-C Solid Waste Burial Ground  

SciTech Connect

This cleanup verification package documents completion of remedial action for the 118-C-1, 105-C Solid Waste Burial Ground. This waste site was the primary burial ground for general wastes from the operation of the 105-C Reactor and received process tubes, aluminum fuel spacers, control rods, reactor hardware, spent nuclear fuel and soft wastes.

M. J. Appel and J. M. Capron

2007-07-25

241

Physical retrieval of precipitation cell parameters using passive 118-GHz observations  

NASA Technical Reports Server (NTRS)

Physical retrieval of precipitation parameters from 118-GHz spectra is investigated using an iterative planar-stratified numerical radiative-transfer model. Liquid and frozen hydrometeors are modeled as spherical Marshall-Palmer and Sekhon-Srivastava (SS) distributed Mie-scattering polydispersions, respectively, with Henyey-Greenstein phase functions. A comparison of 118-GHz rain-cell spectral perturbations observed during Cohmex with model calculations based on coincident radar data yields + or - 10 percent agreement over the convective core region, although a mean ice size 50 percent larger than that given by the SS distribution is required for agreement over the anvil region. A rain-cell model parameterized by top-altitude and total water density suggests that the dominant 118-GHz spectral modes can be used to retrieve top-layer altitude with rms errors of about 1-1.5 km, consistent with statistical retrieval results. Model calculations also suggest that cell density is not observable using 118-GHz spectra alone.

Gasiewski, A. J.; Staelin, D. H.

1989-01-01

242

7 CFR 1955.118 - Processing cash sales or MFH credit sales on NP terms.  

Code of Federal Regulations, 2010 CFR

...MANAGEMENT Disposal of Inventory Property Rural Housing (rh) Real Property § 1955.118 Processing cash sales or MFH...facilitate the sale, the note amount may be amortized using a 30-year factor with payment in full (balloon payment) due...

2010-01-01

243

42 CFR 84.118 - Half-mask facepieces, full facepieces, and mouthpieces; fit; minimum requirements.  

Code of Federal Regulations, 2012 CFR

...APPROVAL OF RESPIRATORY PROTECTIVE DEVICES Gas Masks § 84.118 Half-mask facepieces...respiratory protective qualities of the gas mask. (c) Half-mask facepieces shall...facepiece tests in § 84.124. (d) Gas masks with mouthpieces shall be...

2012-10-01

244

Male circumcision, religion, and infectious diseases: an ecologic analysis of 118 developing countries  

Microsoft Academic Search

BACKGROUND: Both religious practices and male circumcision (MC) have been associated with HIV and other sexually-transmitted infectious diseases. Most studies have been limited in size and have not adequately controlled for religion, so these relationships remain unclear. METHODS: We evaluated relationships between MC prevalence, Muslim and Christian religion, and 7 infectious diseases using country-specific data among 118 developing countries. We

Paul K Drain; Daniel T Halperin; James P Hughes; Jeffrey D Klausner; Robert C Bailey

2006-01-01

245

The ternary system cerium-palladium-silicon  

SciTech Connect

Phase relations in the ternary system Ce-Pd-Si have been established for the isothermal section at 800 deg. C based on X-ray powder diffraction and EMPA techniques on about 130 alloys, which were prepared by arc-melting under argon or powder reaction sintering. Eighteen ternary compounds have been observed to participate in the phase equilibria at 800 deg. C. Atom order was determined by direct methods from X-ray single-crystal counter data for the crystal structures of tau{sub 8}-Ce{sub 3}Pd{sub 4}Si{sub 4} (U{sub 3}Ni{sub 4}Si{sub 4}-type, Immm; a=0.41618(1), b=0.42640(1), c=2.45744(7) nm), tau{sub 16}-Ce{sub 2}Pd{sub 14}Si (own structure type, P4/nmm; a=0.88832(2), c=0.69600(2) nm) and also for tau{sub 18}-CePd{sub 1-x}Si{sub x} (x=0.07; FeB-type, Pnma; a=0.74422(5), b=0.45548(3), c=0.58569(4) nm). Rietveld refinements established the atom arrangement in the structures of tau{sub 5}-Ce{sub 3}PdSi{sub 3} (Ba{sub 3}Al{sub 2}Ge{sub 2}-type, Immm; a=0.41207(1), b=0.43026(1), c=1.84069(4) nm) and tau{sub 13}-Ce{sub 3-x}Pd{sub 20+x}Si{sub 6} (0<=x<=1, Co{sub 20}Al{sub 3}B{sub 6}-type, Fm3-barm; a=1.21527(2) nm). The ternary compound Ce{sub 2}Pd{sub 3}Si{sub 3} (structure-type Ce{sub 2}Rh{sub 1.35}Ge{sub 4.65}, Pmmn; a=0.42040(1), b=0.42247(1), c=1.72444(3) nm) was detected as a high-temperature compound, however, does not participate in the equilibria at 800 deg. C. Phase equilibria in Ce-Pd-Si are characterized by the absence of cerium solubility in palladium silicides. Mutual solubility among cerium silicides and cerium-palladium compounds are significant whereby random substitution of the almost equally sized atom species palladium and silicon is reflected in extended homogeneous regions at constant Ce-content such as for tau{sub 2}-Ce(Pd{sub x}Si{sub 1-x}){sub 2} (AlB{sub 2}-derivative type), tau{sub 6}-Ce(Pd{sub x}Si{sub 1-x}){sub 2} (ThSi{sub 2}-type) and tau{sub 7}-CePd{sub 2-x}Si{sub 2+x}. The crystal structures of compounds tau{sub 4}-Ce{sub a}pprox{sub 8}Pd{sub a}pprox{sub 46}Si{sub a}pprox{sub 46}, tau{sub 12}-Ce{sub a}pprox{sub 29}Pd{sub a}pprox{sub 49}Si{sub a}pprox{sub 22}, tau{sub 15}-Ce{sub a}pprox{sub 22}Pd{sub a}pprox{sub 67}Si{sub a}pprox{sub 11}, tau{sub 17}-Ce{sub a}pprox{sub 5}Pd{sub a}pprox{sub 77}Si{sub a}pprox{sub 18} and tau{sub 18}-CePd{sub 1-x}Si{sub x} (xapprox0.1) are still unknown. - Abstract: Phase relations in the ternary system Ce-Pd-Si have been established for the isothermal section at 800 deg. C based on X-ray powder diffraction, metallography, SEM and EMPA techniques on about 130 alloys. 18 ternary compounds were observed. Display Omitted

Lipatov, Alexey [Institute of Physical Chemistry, University of Vienna, Waehringerstrasse 42, A-1090 Wien (Austria); Materials Science Department of the Moscow State University, Leninskie Gory, GSP-1, 119991 Moscow (Russian Federation); Gribanov, Alexander [Institute of Physical Chemistry, University of Vienna, Waehringerstrasse 42, A-1090 Wien (Austria); Chemistry Department of the Moscow State University, Leninskie Gory, GSP-1, 119991 Moscow (Russian Federation); Grytsiv, Andriy [Institute of Physical Chemistry, University of Vienna, Waehringerstrasse 42, A-1090 Wien (Austria); Rogl, Peter, E-mail: peter.franz.rogl@univie.ac.a [Institute of Physical Chemistry, University of Vienna, Waehringerstrasse 42, A-1090 Wien (Austria); Murashova, Elena; Seropegin, Yurii [Chemistry Department of the Moscow State University, Leninskie Gory, GSP-1, 119991 Moscow (Russian Federation); Giester, Gerald [Institute of Mineralogy and Crystallography, University of Vienna, Althanstrasse 14, A-1090 Wien (Austria); Kalmykov, Konstantin [Chemistry Department of the Moscow State University, Leninskie Gory, GSP-1, 119991 Moscow (Russian Federation)

2009-09-15

246

On the corrosion behavior and biocompatibility of palladium-based dental alloys  

NASA Astrophysics Data System (ADS)

Palladium-based alloys have been used as dental restorative materials for about two decades with good clinical history. But there have been clinical case reports showing possible allergy effects from these alloys. The aim of this study was to characterize the corrosion behavior and mechanisms of several palladium-based dental alloys by potentiodynamic polarization methods, electrochemical impedance spectroscopy (EIS), and scanning Kelvin probe force microscopy/atomic force microscopy (SKPFM/AFM), and to evaluate their biocompatibility by a cell culture technique and an animal model. Using SKPFM/AFM and scanning electron microscopy, the Ru-enriched phase from the use of ruthenium as a grain-refining element was identified as being slightly more noble than the palladium solid solution matrix in a high-palladium alloy. Other secondary precipitates that exist in the microstructures of these high-palladium alloys have minimal differences in Volta potential compared to the matrix. For high-palladium alloys, corrosion is generally uniform due to the predominant palladium content in the different phases. Potentiodynamic polarization and EIS have shown that representative palladium-silver alloys have low corrosion tendency and high corrosion resistance, which are equivalent to a well-known high-noble gold-palladium alloy in simulated body fluid and oral environments. The palladium-silver alloys tested are resistant to chloride ion corrosion. Passivation and dealloying have been identified for all of the tested palladium-silver alloys. The great similarity in corrosion behavior among the palladium-silver alloys is attributed to their similar chemical compositions. The variation in microstructures of palladium-silver alloys tested does not cause significant difference in corrosion behavior. The corrosion resistance of these palladium-silver alloys at elevated potentials relevant to oral environment is still satisfactory. The release of elements from representative dental palladium alloys into cell culture media did not significantly affect the proliferation and viability of human fibroblast cells. Subcutaneous implantation of samples of one high-palladium alloy, one palladium-silver alloy and a gold alloy into mice did not cause any significant histological change in their skin and spleen. The presence of an oxide layer from dental laboratory processing of these alloys did not cause any adverse reactions from the cells or animals. The biocompatibility of the dental palladium-based alloys evaluated by the cell culture and animal models is satisfactory, suggesting that these alloys are safe for clinical usage.

Sun, Desheng

247

ACTS 118x Final Report High-Speed TCP Interoperability Testing  

NASA Technical Reports Server (NTRS)

With the recent explosion of the Internet and the enormous business opportunities available to communication system providers, great interest has developed in improving the efficiency of data transfer using the Transmission Control Protocol (TCP) of the Internet Protocol (IP) suite. The satellite system providers are interested in solving TCP efficiency problems associated with long delays and error-prone links. Similarly, the terrestrial community is interested in solving TCP problems over high-bandwidth links. Whereas the wireless community is interested in improving TCP performance over bandwidth constrained, error-prone links. NASA realized that solutions had already been proposed for most of the problems associated with efficient data transfer over large bandwidth-delay links (which include satellite links). The solutions are detailed in various Internet Engineering Task Force (IETF) Request for Comments (RFCs). Unfortunately, most of these solutions had not been tested at high-speed (155+ Mbps). Therefore, the NASA's ACTS experiments program initiated a series of TCP experiments to demonstrate scalability of TCP/IP and determine how far the protocol can be optimized over a 622 Mbps satellite link. These experiments were known as the 118i and 118j experiments. During the 118i and 118j experiments, NASA worked closely with SUN Microsystems and FORE Systems to improve the operating system, TCP stacks. and network interface cards and drivers. We were able to obtain instantaneous data throughput rates of greater than 520 Mbps and average throughput rates of 470 Mbps using TCP over Asynchronous Transfer Mode (ATM) over a 622 Mbps Synchronous Optical Network (SONET) OC12 link. Following the success of these experiments and the successful government/industry collaboration, a new series of experiments. the 118x experiments. were developed.

Ivancic, William D.; Zernic, Mike; Hoder, Douglas J.; Brooks, David E.; Beering, Dave R.; Welch, Arun

1999-01-01

248

Elucidating reactivity differences in palladium-catalyzed coupling processes: the chemistry of palladium hydrides.  

PubMed

This communication describes a series of studies directed at obtaining a better understanding of the Heck reaction. For the first time, the postulated palladium-hydride intermediate (L2PdHX) in the catalytic cycle of the Heck arylation has been identified. In addition, this study establishes that the base-mediated Pd(0)-regeneration step (L2PdHX --> PdL2) of the cycle can be kinetically slow and thermodynamically unfavorable and that the process is remarkably sensitive to the structure of L (PCy3 vs P(t-Bu)3). Finally, this investigation demonstrates that, for certain catalyst systems, slow rates of Heck arylation can be correlated with reluctant reductive elimination of L2PdHX, furnishing a possible rationalization for Brønsted-base (Cs2CO3 vs Cy2NMe) and ligand (PCy3 vs P(t-Bu)3) effects that have been observed. PMID:15479044

Hills, Ivory D; Fu, Gregory C

2004-10-20

249

Palladium catalyzed heck arylation of 2,3-dihydrofuran-effect of the palladium precursor.  

PubMed

Heck arylation of 2,3-dihydrofuran with iodobenzene was carried out in systems consisting of different palladium precursors (Pd2(dba)3, Pd(acac)2, PdCl2(cod), [PdCl(allyl)]2, PdCl2(PhCN)2, PdCl2(PPh3)2) and ionic liquids (CILs) with L-prolinate or L-lactate anions. All the tested CILs caused remarkable increases of the conversion values and in all of the reactions 2-phenyl-2,3-dihydrofuran (3) was obtained as the main product with a yield of up to 59.2%. The highest conversions of iodobenzene were achieved for the [PdCl(allyl)]2 precursor. Formation of Pd(0) nanoparticles, representing the resting state of the catalyst, was evidenced by TEM. PMID:24950443

Morel, Adam; Trzeciak, Anna M; Pernak, Juliusz

2014-01-01

250

Palladium nanoparticles produced by CW and pulsed laser ablation in water  

NASA Astrophysics Data System (ADS)

Palladium nanoparticles are receiving important interest due to its application as catalyst. In this work Pd nanoparticles have been obtained by ablating a Pd target submerged in de-ionized using both, pulsed as well as continuous wave (CW) laser. The influence of laser parameters involved in the formation in nanoparticles has been studied. Crystalline phases, morphology and optical properties of the obtained colloidal nanoparticles were characterized by means of transmission electron microscopy (TEM), high resolution transmission electron microscopy (HRTEM) and UV/vis absorption spectroscopy. The obtained colloidal suspensions consisted of pure Pd nanoparticles showing spherical shape with diameters ranging from few nanometers to 5-60 nm. The moderate irradiance delivered by the CW laser favours high production of uniform nanoparticles.

Boutinguiza, M.; Comesaña, R.; Lusquiños, F.; Riveiro, A.; del Val, J.; Pou, J.

2014-05-01

251

An intravenous (i.v.) route-compatible formulation of FL118, a survivin, Mcl-1, XIAP, and cIAP2 selective inhibitor, improves FL118 antitumor efficacy and therapeutic index (TI)  

PubMed Central

We recently reported a novel anticancer small molecule, designated FL118, which was discovered via high throughput screening (HTS), and followed by hit-lead in vitro and in vivo analysis. FL118 selectively inhibits the expression of four major cancer survival-associated gene products (survivin, Mcl-1, XIAP, and cIAP2) and shows promising antitumor activity in animal models of human cancers when administered using a weekly x 4 schedule (Ling et al., PLOS ONE. 2012, 7: e45571). Here, we compared the antitumor efficacy and therapeutic index (TI) of FL118 in a newly developed Tween 80-free formulation that can be delivered intravenously (i.v.) and intraperitoneally (i.p.) against the previous Tween 80-containing formulation that can only be delivered via an i.p. route. We found that the maximum tolerated dose (MTD) for FL118 in the i.v. formulation increases 3-7 fold in comparison with the MTD of FL118 in the i.p. formulation. FL118 in the i.v. recipe was able to eliminate human tumor xenografts in all three major schedules tested (daily x 5, q2 x 5 and weekly x 5). In contrast, FL118 was able to eliminate human tumor xenografts in the i.p. formulation only with the weekly x 4 schedule previously reported. The TI of FL118 in the i.v. formulation reached 5-6 in the most effective schedule, while the TI of FL118 in the i.p. formulation was only 1.3 - 2. These findings overcome several clinical challenges including FL118 formulation to realize clinically compatible drug administration routes, and expanding effective treatment schedules. The striking improvement of the TI makes FL118 a much safer drug for further development toward clinical trials.

Ling, Xiang; Li, Fengzhi

2013-01-01

252

Initiation of electroless nickel plating on copper, palladium-activated copper, gold, and platinum  

SciTech Connect

The catalytic activity of copper, palladium-activated copper, gold, and platinum for electro-oxidation of hypophosphite and electroless nickel plating was investigated in an ammoniacal solution of pH 8.8 at 50/sup 0/C by potential measurements and linear sweep voltammetry from -0.3 to -0.92V vs. SCE. Early stages of nickel plating on copper-palladium substrates were studied by scanning electron microscopy in conjunction with EDAX. It was found that palladium-activated copper and gold were catalytically active in the entire range of potentials examined; copper was active below -0.6 platinum was not active at all. Small amounts of electrolytically deposited nickel considerably increased the electro-oxidation rate of hypophosphite on copper, gold, and palladium. TEM examinations showed that activation of copper in a PdCl/sub 2//HCl solution resulted in the deposition of palladium in the form of separate patches. Electroless nickel deposition on copper substrates with separate palladium spots took place on copper and palladium independently of each other. The deposition on palladium was faster than that on copper. It was concluded that the activation of copper substrates around palladium spots occurred solely through a spontaneous potential shift, induced by electro-oxidation of hypophosphite on the palladium spots. It was suggested that small amounts of one metal synergistically enhanced the catalytic activity of the other metals.

Flis, J.; Duquette, D.J.

1984-02-01

253

Hydrogen storage studies of palladium decorated nitrogen doped graphene nanoplatelets.  

PubMed

Hydrogen storage in materials is of significant importance in the present scenario of depleting conventional energy sources. Porous solids such as activated carbon or nanostructured carbon materials have promising future as hydrogen storage media. The hydrogen storage capacity in nanostructured carbon materials can be further enhanced by atomic hydrogen spillover from a supported catalyst. In the present work, the hydrogen storage properties of nitrogen doped graphene nanoplatelets (N-GNP) and palladium decorated nitrogen doped graphene nanoplatelets (Pd/N-GNP) have been investigated. The results show that hydrogen uptake capacity of nitrogen doped graphene nanoplatelets and palladium decorated nitrogen doped graphene nanoplatelets at pressure 32 bar and temperature 25 degrees C is 0.42 wt% and 1.25 wt% respectively. The dispersion of palladium nanoparticles increases the hydrogen storage capacity of nitrogen doped graphene nanoplatelets by 0.83 wt%. This may be due to high dispersion of palladium nanoparticles and strong adhesion between metal and graphene nanoplatelets over the surface of N-GNP, which enhances the spillover mechanism. Thus, an increase in the hydrogen spillover effect and the binding energy between metal nanoparticles and supporting material achieved by nitrogen doping has been observed to result in a higher hydrogen storage capacity of pristine GNP. PMID:22962796

Vinayan, B P; Sethupathi, K; Ramaprabhu, S

2012-08-01

254

Palladium Nanowires Assembly by Dielectrophoresis Investigated as Hydrogen Sensors  

Microsoft Academic Search

Fabrication of hydrogen sensors based on array of palladium nanowires onto silicon substrate with interdigitated electrodes is reported. Two series of devices, where Pd-sensing elements are assembled by dielectrophoresis, are fabricated and electrically characterized under 4% hydrogen at room temperature. Their electrical responses are analyzed and compared to investigate the effect of nanowire thickness and surface morphology on sensitivity and

Vera La Ferrara; Brigida Alfano; Ettore Massera; Girolamo Di Francia

2008-01-01

255

Fibre optics in palladium-based hydrogen sensing  

Microsoft Academic Search

Hydrogen sensing at low concentrations in the order of tens to hundreds of parts per million ( ppm) over extended periods requires highly sensitive and stable sensor technology. Palladium and its alloys are widely used in hydrogen sensing as they show a high and selective affinity for hydrogen. On exposure to hydrogen, Pd experiences a volumetric expansion, roughly proportional to

R. R. J. Maier; B. J. S. Jones; J. S. Barton; S. McCulloch; T. Allsop; J. D. C. Jones; I. Bennion

2007-01-01

256

Optical fibre hydrogen sensors based on palladium coatings  

NASA Astrophysics Data System (ADS)

Optical fibre sensors for Hydrogen detection at low concentrations has become a growing research area using Palladium as an active medium. Palladium is widely used in hydrogen sensing as it show a high and selective affinity for hydrogen. This metal is capable to absorb hydrogen up to 900 times its own volume which permits that during the expansion mechanical forces are applied in the fibre modifying the optical response. Several optical fibre hydrogen sensor heads coated with Palladium are presented and compared using different working principles: interferometric, intensity and fiber grating-based sensors. These principles were applied in Fabry-Perot cavities, fibre Bragg gratings written in fibre SMF28 with etching in the cladding, multimode interferometers and fibre end micro-mirrors. Palladium thin film coatings over the fibre surface and with thicknesses from 10nm to 350nm were produced by using the sputtering RF technique. These studies were performed in a Hydrogen/Nitrogen atmosphere with Hydrogen concentrations from 0% to 4% (lower limit explosion). The Bragg grating inscribed in a fibre with reduced cladding diameter appears to be one of the best approaches for a fibre optic sensing head for Hydrogen detection. Future work will continue the investigation of other fibre optic structures with Hydrogen sensing capabilities and their application in specific field situations will be assessed.

Coelho, L.; Silva, S. F. O.; Tafulo, Paula A. R.; Santos, J. L.; Frazão, O.; Malcata, F. X.

2011-05-01

257

Room-temperature hydrogen sensor based on palladium nanowires  

Microsoft Academic Search

Palladium (Pd) nanowires, synthesized by template-nanomanufacturing techniques, has been studied for hydrogen gas-sensing applications at room temperature. In this study, parallel arrays of Pd nanowires were fabricated by electrodeposition from an aqueous plating solution onto the surface of highly oriented pyrolytic graphite (HOPG). The nanowires were then transferred onto a polystyrene film and silver electrical contact pads were fabricated by

Massood Z. Atashbar; D. Banerji; S. Singamaneni

2005-01-01

258

Electrochemical Energy Conversion in a Palladium Hydrogen Diffusion Electrode.  

National Technical Information Service (NTIS)

A high efficiency palladium-hydrogen diffusion electrode has been developed. Current densities of 165 ma/cm are achieved at 30C on 0.010 inch wall electrodes after pretreatment by abrading and oxidizing in air at 800C. Hydrogen transport is governed by so...

H. J. Cleary N. D. Greene

1964-01-01

259

Operation of platinum-palladium catalysts with leaded gasoline.  

PubMed Central

The effect of various fuel additives on the ability of platinum-palladium catalytic converters to remove the carbon monoxide and hydrocarbon components of automotive exhaust has been examined. Engine dynamometer studies suggest that these catalysts may be successfully used in conjunction with fuels of relatively high tetraethyllead concentrations, provided the ethylene dibromide portion of the scavenger is excluded.

Teague, D M; Clougherty, L B; Speca, A N

1975-01-01

260

Electrical resistivity of copper, gold, palladium, and silver  

Microsoft Academic Search

In this work, recommended values for the electrical resistivity as a function of temperature from the cryogenic region to well beyond the melting point are given for bulk pure copper, gold, palladium, and silver. In addition to the total electrical resistivity values for the solid state, intrinsic electrical resistivity values are presented from cryogenic temperatures to the melting point. The

R. A. Matula

1979-01-01

261

Discovery of palladium, antimony, tellurium, iodine, and xenon isotopes  

SciTech Connect

Currently, thirty-eight palladium, thirty-eight antimony, thirty-nine tellurium, thirty-eight iodine, and forty xenon isotopes have been observed and the discovery of these isotopes is described here. For each isotope a brief synopsis of the first refereed publication, including the production and identification method, is presented.

Kathawa, J.; Fry, C.; Thoennessen, M., E-mail: thoennessen@nscl.msu.edu

2013-01-15

262

Characteristics of magnetism in nanoporous carbon with palladium clusters  

Microsoft Academic Search

The magnetic properties of samples of nanoporous carbon with palladium clusters prepared from polycrystalline SiC have been studied over a wide range of temperatures. The specific magnetic moment rapidly decreases with increasing temperature. The obtained experimental magnetization curves have a nonlinear character but do not reach saturation even in a field of 10 kOe. Being constructed as functions of H\\/

A. M. Danishevskii; T. L. Makarova; A. A. Sitnikova; B. D. Shanina

2011-01-01

263

Palladium-catalyzed direct arylation of indoles with cyclohexanones.  

PubMed

A novel palladium catalyzed approach to 3-arylindoles was developed from indoles and cyclohexanones. Various cyclohexanones acted as aryl sources via an alkylation and dehydrogenation sequence using molecular oxygen as the hydrogen acceptor. This method showed good regioselectivity and afforded 3-arylindoles as the sole products. PMID:24597845

Chen, Shanping; Liao, Yunfeng; Zhao, Feng; Qi, Hongrui; Liu, Saiwen; Deng, Guo-Jun

2014-03-21

264

Palladium-Catalyzed Coupling Reactions of Aryl Chlorides  

Microsoft Academic Search

Collectively, palladium-catalyzed cou- pling reactions represent some of the most powerful and versatile tools avail- able to synthetic organic chemists. Their widespread popularity stems in part from the fact that they are gen- erally tolerant to a large number of functional groups, which allows them to be employed in a wide range of applications. However, for many years a major

Adam F. Littke; Gregory C. Fu

2002-01-01

265

An integrated optic hydrogen sensor based on SPR on palladium  

Microsoft Academic Search

A small and efficient hydrogen sensor using surface plasmon resonance in an integrated optical waveguide is reported. The waveguide properties are influenced by a thin palladium layer whose optical constants depend on concentration of hydrogen in surrounding gaseous medium. A modal analysis of the sensor structure is performed and a simple sensor model is proposed. Finally, experimental results are presented;

Petr Tobiška; Olivier Hugon; Alain Trouillet; Henri Gagnaire

2001-01-01

266

Elastic and Inelastic Proton Scattering from Even Palladium Isotopes.  

National Technical Information Service (NTIS)

Aspects of scattering experiments from palladium isotopes are discussed. Five even Pd isotopes are selected to study anharmonicities in the low-lying spectrum. Analysis of the 12 MeV and 52 MeV experimental data taken from the literature is performed by a...

H. V. von Geramb G. Palla

1980-01-01

267

Silver-palladium braze alloy recovered from masking materials  

NASA Technical Reports Server (NTRS)

Method for recovering powdered silver-palladium braze alloy from an acrylic spray binder and rubber masking adhesive used in spray brazing is devised. The process involves agitation and dissolution of masking materials and recovery of suspended precious metal particles on a filter.

Cierniak, R.; Colman, G.; De Carlo, F.

1966-01-01

268

Thermal neutron capture cross sections of the palladium isotopes  

SciTech Connect

Precise thermal neutron capture {gamma}-ray cross sections {sigma}{sub {gamma}} were measured for all elements with Z=1-83,90, and 92, for He and Pm, at the Budapest Reactor. These data were evaluated with additional information from the literature to generate the Evaluated Gamma-ray Activation File (EGAF). Isotopic radiative neutron cross sections can be deduced from the total transition cross section feeding the ground state, {sigma}{sub 0}={sigma}{sigma}{sub {gamma}}(GS) if the decay scheme is complete. The EGAF file contains partial {gamma}-ray cross sections for all stable palladium isotopes. None of these decay schemes are complete, although in each case transitions de-exciting low-lying levels are known. We have performed Monte Carlo simulations of the palladium thermal neutron capture decay schemes using the computer code DICEBOX. The simulated populations of low low-lying levels are normalized to the measured {sigma}{sub {gamma}} values from EGAF and the total radiative neutron cross section {sigma}{sub 0} is obtained. The {sigma}{sub 0} values derived for the palladium isotopes agree well with previous measurements and were in several cases more precise. Complementary use of {gamma}-ray cross-section data and Monte Carlo calculations has proven effective in determining both the palladium total radiative cross sections and new nuclear structure information.

Krticka, M. [Charles University in Prague, Faculty of Mathematics and Physics, V Holesovickach 2, CZ-180 00 Prague 8 (Czech Republic); North Carolina State University, Raleigh, NC 27695 (United States); Firestone, R. B. [Lawrence Berkeley National Laboratory, Berkeley, CA 94720 (United States); McNabb, D. P.; Sleaford, B.; Agvaanluvsan, U. [Lawrence Livermore National Laboratory, L-414, 7000 East Avenue, Livermore, CA 94551 (United States); Belgya, T.; Revay, Z. S. [Institute of Isotope and Surface Chemistry, H-1525, Budapest (Hungary)

2008-05-15

269

STRONTIUM AS AN EFFICIENT PROMOTER FOR SUPPORTED PALLADIUM HYDROGENATION CATALYSTS  

EPA Science Inventory

The effect of strontium promotion is studied for a series of supported palladium catalysts such as Pd/zeolite-?, Pd/Al2O3, Pd/SiO2, Pd/hydrotalcite and Pd/MgO. Strontium is found to be an effective promoter for enhancing the metal area, perce...

270

The Adsorption and Diffusion of Electrolytic Hydrogen in Palladium  

Microsoft Academic Search

A sensitive electrochemical technique, which permits the recording of the instantaneous rate of permeation of electrolytic hydrogen through palladium, is described. Results were obtained under conditions required by theory for the diffusion of hydrogen with the use of electronic potentiostats. Analysis of the results shows the validity of the equations previously deduced for the diffusion of hydrogen. No anomalies in

M. A. V. Devanathan; Z. Stachurski

1962-01-01

271

Palladium-109 labeled anti-melanoma monoclonal antibodies  

DOEpatents

The invention consists of new monoclonal antibodies labelled with Palladium 109, a beta-emitting radionuclide, the method of preparing this material, and its use in the radiotherapy of melanoma. The antibodies are chelate-conjugated and demonstrate a high uptake in melanomas. (ACR)

Srivastava, S.C.; Fawwaz, R.A.; Ferrone, S.

1984-04-30

272

Electrochemical Properties of Palladium and Platinum Phosphine Complexes.  

National Technical Information Service (NTIS)

The electrochemistry of 11 palladium (II) and platinum (II) complexes of the type ML2X2(L = P, N, or C-donor; X = Cl or I) was examined by cyclic voltammetry in nonaqueous solution. Electrochemical reduction was irreversible and was coupled with loss of X...

J. M. Calvert B. H. Berrie R. J. Nowak J. C. Cooper

1985-01-01

273

CATALYTIC COMBUSTION OF METHANE OVER PALLADIUM-BASED CATALYSTS  

Microsoft Academic Search

Palladium-based catalysts are widely applied in exhaust catalytic converter and catalytic combustion systems. The mechanism for methane oxidation on a Pd-based catalyst is complex. Catalyst activity is influenced by variations in the process pressure and temperature, by the gas mixture composition, by the type of support and various additives, and by pretreatment under reducing or oxidizing atmospheres. In this paper,

Dragos Ciuparu; Maxim R. Lyubovsky; Eric Altman; Lisa D. Pfefferle; Abhaya Datye

2002-01-01

274

Reactions of laser-ablated platinum and palladium atoms with dioxygen. Matrix infrared spectra and density functional calculations of platinum oxides and complexes and palladium complexes  

Microsoft Academic Search

The interaction of small gas molecules with bulk platinum and palladium is currently an area of intensive research. Much of this research has focused on the adsorption of these species (specifically Oâ, Nâ, and CO) on noble metal surfaces or on the catalytic reactions of such adsorbed species. Also important are the reactions of dissolved gases on platinum and palladium

William D. Bare; Angelo Citra; George V. Chertihin; Lester Andrews

1999-01-01

275

Characterization of the {beta}-phase of the palladium-hydrogen equation of state  

SciTech Connect

The {beta}-phase of the P-C-T curves of the palladium-hydrogen system is encountered at high pressures of gaseous hydrogen and low temperatures of this system. The {beta}-phase is characterized by an increase in the concentration of hydrogen in the palladium lattice with an increase in pressure of the free hydrogen gas surrounding the palladium. The P-C-T curves in this study are determined by gravimetric measurements of the hydrided palladium sample to determine the amount of hydrogen within the palladium lattice. The amount of hydrogen is kept constant within the experimental system and the temperature is varied which changes the pressures. The objective of this experimental thesis is to accurately determine the P-C-T curves of palladium in the {beta}-phase region to pressures of 20,000 psia and medium to low temperature region of {minus}60 C to 100 C.

Fisher, K.J.

1998-07-01

276

42 CFR 413.118 - Payment for facility services related to covered ASC surgical procedures performed in hospitals...  

Code of Federal Regulations, 2013 CFR

...performed in hospitals on an outpatient basis. 413.118 Section 413.118 Public Health CENTERS FOR MEDICARE...SERVICES, DEPARTMENT OF HEALTH AND HUMAN SERVICES...performed in hospitals on an outpatient basis. (a) Basis...by an ASC in the same geographic area. (c)...

2013-10-01

277

Vapor space characterization of waste tank 241-TX-118: Results from samples collected on 12/16/94.  

National Technical Information Service (NTIS)

This report describes inorganic and organic analyses results from samples obtained from the headspace of the Hanford waste storage Tank 241-TX-118 (referred to as Tank TX-118). The results described here were obtained to support safety and toxicological e...

R. B. Lucke M. W. Ligotke B. D. McVeety

1995-01-01

278

Does NPHS1 polymorphism modulate P118l mutation in NPHS2?  

PubMed

Nephrotic syndrome (NS) in the first year of life is uncommon and makes up a heterogeneous group of disorders. Subsequent studies have further defined the phenotype associated with mutations in the NPHS2 gene, revealing that patients usually develop NS from birth to 6 years of age. We report a child aged 4 months with steroid-resistant NS who had polymorphism of NPHS1 (E117K) and mutation of NPHS2 (P118L). Our patient was carrying a polymorphic NPHS1 mutation, while phenotypically she had a poor prognostic NPHS2 mutation. However, it must be questioned whether this polymorphic change (E117K) alters the signaling pathways of the podocytes and leads to P118L mutation, thus making it behave differently. Perhaps, this would be called a genetic modifier in future. PMID:24231487

Dincel, Nida; Mir, Sevgi; Berdeli, Afig; Bulut, Ipek Kaplan; Sozeri, Betul

2013-11-01

279

Palladium thin film deposition on polyimide by CW Ar + laser radiation for electroless copper plating  

Microsoft Academic Search

Ar+ laser radiation (CW, 488 nm) is used to induce deposition of palladium (Pd) thin films onto polyimide surfaces from palladium–amine {[Pd(NH3)4]2+} solutions. The chemical reaction is carried out by formaldehyde-assisted reduction of palladium–amine complex molecules to metallic Pd, and is localized on the polymer substrate by a focused and scanned Ar+ laser beam. The narrow (6–14 ?m), homogeneous and

K. Kordás; S. Leppävuori; A. Uusimäki; Thomas F. George; L. Nánai; R. Vajtai; K. Bali; J. Békési

2001-01-01

280

Banana peel extract mediated novel route for the synthesis of palladium nanoparticles  

Microsoft Academic Search

Bio-inspired palladium nanoparticles were synthesized by using banana peel extract (BPE), a non-toxic eco-friendly material. Boiled, crushed, acetone precipitated, air-dried peel powder was used to reduce palladium chloride. The palladium nanoparticles were characterized by using UV–Visible spectroscopy, scanning electron microscope-energy dispersive spectra (SEM-EDS) and X-ray diffraction (XRD) analysis. Dynamic light scattering (DLS) studies revealed the average size of nanoparticles to

Ashok Bankar; Bhagyashree Joshi; Ameeta Ravi Kumar; Smita Zinjarde

2010-01-01

281

Palladium nanoparticle-graphene hybrids as active catalysts for the Suzuki reaction  

Microsoft Academic Search

Graphene has been successfully modified with palladium nanoparticles in a facile manner by reducing palladium acetate [Pd(OAc)2] in the present of sodium dodecyl sulfate (SDS), which is used as both surfactant and the reducing agent. The palladium nanoparticle-graphene\\u000a hybrids (Pd-graphene hybrids) are characterized by high-resolution transmission electron microscopy, atomic force microscopy,\\u000a Raman spectroscopy, X-ray photoelectron spectroscopy, X-ray diffraction, and energy

Yang Li; Xiaobin Fan; Junjie Qi; Junyi Ji; Shulan Wang; Guoliang Zhang; Fengbao Zhang

2010-01-01

282

Aqueous-Phase Palladium-Catalyzed Coupling. A Green Chemistry Laboratory Experiment  

NASA Astrophysics Data System (ADS)

An upper-level inorganic/organic experiment presents important concepts in modern green chemistry. A water-soluble modified triphenylphosphine ligand is prepared and used to prepare a water-soluble palladium catalyst. The palladium catalyst is formed in situ and used for the aqueous, homogenous, palladium-catalyzed cross-coupling reaction of iodobenzene and diethyl phosphite. The product is diethyl phenylphosphonate.

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Harper, Brandy A.; Chance Rainwater, J.; Birdwhistell, Kurt; Knight, D. Andrew

2002-06-01

283

Photooxidation of xylenol orange in the presence of palladium-modified TiO 2 catalysts  

Microsoft Academic Search

The decolouring and the degradation of xylenol orange in aqueous solution photocatalyzed by band-gap-irradiated TiO2, modified with nanosized palladium particles has been studied. The photocatalytic activity of TiO2, modified with palladium, is higher than that of the semiconductig support. The adsorption properties of the catalysts, as well as the size of the palladium clusters on the surface of the support,

V. Iliev; D. Tomova; L. Bilyarska; L. Petrov

2004-01-01

284

1,3-butadiene telomerization with methanol catalyzed by heterogenized palladium complexes  

Microsoft Academic Search

The heterogenization of palladium complexes on silica as well as on functionalized styrene\\/divinylbenzene crosslinked resins and linear poly(styrene) is described. In particular, palladium (0) and palladium (II) derivatives were anchored to the above polymeric systems through their functionalization with bidentate ligands such as acetylacetonate and 1,3-bis(diphenylphosphino)propane moieties. The resulting heterogenized complexes were checked in the catalytic telomerization of 1,3-butadiene with

Federica Benvenuti; Carlo Carlini; Anna Maria Raspolli Galletti; Glauco Sbrana; Mario Marchionna; Renata Patrini

1999-01-01

285

A Quantitative Consideration for Template Effect of Palladium(II) Using N-[Pyridylmethyl] Chitosan  

Microsoft Academic Search

Crosslinked N-[pyridylmethyl]chitosan (PMC) incorporating pyridine moiety and the crosslinked palladium(II)-imprinted-N-[pyridylmethyl]chitosan (PIPMC) were synthesized to elucidate the template effect of palladium(II) in the adsorption of metals from hydrochloric acid. The adsorption selectivity for metal ions from hydrochloric acids on PIPMC was compared with that on PMC. PIPMC exhibited the high selectivity towards not only palladium(II), but also gold(III), nickel(II), and copper(II)

Yoshinari Baba; Tatsuya Oshima; Shintaro Kanemaru

2011-01-01

286

Liquid phase oxidation of limonene catalyzed by palladium supported on hydrotalcites  

Microsoft Academic Search

Palladium supported on copper–magnesium–aluminium hydrotalcites (HTs) were prepared by using coprecipitation and impregnation techniques. The different palladium\\/hydrotalcites solid catalysts were tested in the liquid phase oxidation of pure limonene using molecular oxygen as the sole oxidant agent. Both palladium and copper were found to influence the conversion versus reaction time profile of limonene oxidation. A chain reaction mechanism is proposed

Juan Bussi; Alejandro López; Francisco Peña; Pablo Timbal; Daniel Paz; Daniel Lorenzo; Eduardo Dellacasa

2003-01-01

287

Structure, energetic and phase transition of small nickel-palladium heterogeneous clusters  

NASA Astrophysics Data System (ADS)

Molecular dynamics simulation (MD) with Sutton-Chen potential for palladium-palladium, nickel-nickel and palladium-nickel interactions has been used to generate the minimum energy structures and to study the thermodynamic and dynamic properties of mixed transition metal cluster motifs of Ni n Pd(13- n) for n ? 13. Thirteen particle icosahedral clusters of neat palladium and nickel atoms were first reproduced accordingly with the results in literature. Then in the palladium icosahedra, each palladium atom has been successively replaced by nickel atom. Calculation is repeated for both palladium-centered and nickel-centered clusters. It is found that the nickel-centered clusters are more stable than the palladium-centered clusters and cohesive energy increases along the palladium end to nickel end. Phase transition of each cluster from one end-species to the other end-species is studied by means of caloric curve, root mean square bond fluctuation and heat capacity. Trend in variation of melting temperature is opposite to the energy trend. Palladium-centered cluster shows a premelting at low temperature due to the solid-solid structural transition. Species-centric order parameters developed by Hewage and Amar is used to understand the dynamic behavior in the solid-solid transition of palladium-centered cluster to more stable nickel-centered cluster (premelting). This species-centric order parameter calculation further confirmed the stability of nickel-centered species over those of palladium-centered species and solid-solid structural transition at low temperature.

Hewage, Jinasena W.

2014-06-01

288

Cleanup Verification Package for the 118-B-1, 105-B Solid Waste Burial Ground  

SciTech Connect

This cleanup verification package documents completion of remedial action, sampling activities, and compliance criteria for the 118-B-1, 105-B Solid Waste Burial Ground. This waste site was the primary burial ground for general wastes from the operation of the 105-B Reactor and P-10 Tritium Separation Project and also received waste from the 105-N Reactor. The burial ground received reactor hardware, process piping and tubing, fuel spacers, glassware, electrical components, tritium process wastes, soft wastes and other miscellaneous debris.

J. M. Capron

2008-01-21

289

Design of 11.8MHz Buncher for ISAC at TRIUMF  

Microsoft Academic Search

The high energy beam transport (HEBT) line for the ISAC radioactive beam facility at TRIUMF requires an 11.8 MHz buncher. The main requirements of the buncher are to operate in cw mode with a velocity acceptance of 2.2% and an effective voltage of 100 kV, which for a three gap buncher gives a drift tube voltage of 30 kV. A

Amiya Mitra; R. L. Poirier; R. E. Laxdal

2000-01-01

290

Ionization potentials of internal conversion electrons for the superheavy elements 112, 114, 116, and 118  

NASA Astrophysics Data System (ADS)

K-shell (1s) and L-shell (2s) ionization potentials for the superheavy elements with Z=112, 114, 116, and 118 are predicted to an accuracy of a few 10 eV using Dirac-Hartree-Fock theory and taking into account quantum electrodynamic and nuclear-size effects. The data obtained are for any number of electrons and can be used in the future in theoretical and experimental studies of these elements involving K-electron conversion spectroscopy.

Gaston, Nicola; Schwerdtfeger, Peter; Nazarewicz, Witold

2002-12-01

291

Analysis of 118 second-generation metal-on-metal retrieved hip implants  

Microsoft Academic Search

steolysis is due to particulate wear debris and is responsible for the long-term failure of total hip replacements. It has stimulated the development of alternative joint surfaces such as metal-on-metal or ceramic-on-ceramic implants. Since 1988 the second-generation metal-on-metal implant Metasul has been used in over 60 000 hips. Analysis of 118 retrieved specimens of the head or cup showed rates

H.-P. Sieber; C. B. Rieker; P. Köttig

1999-01-01

292

Calculated and experimental data for a 118-mm bore roller bearing to 3 million DN  

NASA Technical Reports Server (NTRS)

The operating characteristics for 118 mm bore cylindrical roller bearing are examined using the computer program CYBEAN. The predicted results of inner and outer-race temperatures and heat transferred to the lubricant generally compared well with experimental data for shaft speeds to 3 million DN (25,000 rpm), radial loads to 8900 N (2000 lb), and total lubricant flow rates to 0.0102 cu m/min (2.7 gal/min).

Coe, H. H.; Schuller, F. T.

1980-01-01

293

Some ( Gamma , 1PXN) Reactions in exp 118 SN at Intermediate Energies.  

National Technical Information Service (NTIS)

Yield curves for the production of sup(117g)In, sup(117m)In, sup(116m1)In, sup(115m)In, sup(113m)In, sup(111)In, sup(110h)In, sup(110l)In, exp 109 In, sup(108h)In and sup(108l)In from enriched exp 118 Sn have been measured by the activation method in the ...

B. Bulow M. Eriksson G. G. Jonsson E. Hageboe

1975-01-01

294

118. Back side technical facilities S.R. radar transmitter & computer ...  

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

118. Back side technical facilities S.R. radar transmitter & computer building no. 102, "building sections - sheet I" - architectural, AS-BLT AW 35-46-04, sheet 13, dated 23 January, 1961. - Clear Air Force Station, Ballistic Missile Early Warning System Site II, One mile west of mile marker 293.5 on Parks Highway, 5 miles southwest of Anderson, Anderson, Denali Borough, AK

295

Room temperature 0.1 ?m CMOS technology with 11.8 ps gate delay  

Microsoft Academic Search

We report a room temperature, 0.1 ?m CMOS technology on bulk Si substrates that delivers a record ring-oscillator gate delay of 11.8 psec at 2.5 V. Frequency dividers at 2.0 V operate with input frequencies exceeding 8.5 GHz. Feature sizes obey g-line lithography design rules except at the gate level. The high speed CMOS performance and the good subthreshold and

K. F. Lee; R. H. Yan; D. Y. Jeon; G. M. Chin; Y. O. Kim; D. M. Tennant; B. Razavi; H. D. Lin; Y. G. Wey; E. H. Westerwick; M. D. Morris; R. W. Johnson; T. M. Liu; M. Tarsia; M. Cerullo; R. G. Swartz; A. Ourmazd

1993-01-01

296

Formation dynamics of fullerene dimers C118+, C119+, and C120+  

NASA Astrophysics Data System (ADS)

Dumbbell-shaped fullerene dimers C118+ and C119+ have recently been observed in mass spectra resulting from collisions between clusters of C60 molecules and keV He2+ or Ar2+ ions [H. Zettergren et al., Phys. Rev. Lett. 110, 185501 (2013), 10.1103/PhysRevLett.110.185501 and F. Seitz et al., J. Chem. Phys. 139, 034309 (2013), 10.1063/1.4812790]. To unveil the formation mechanisms of these fullerene dimers, systematic molecular dynamics (MD) simulations based on the self-consistent charge density functional tight-binding method have been performed for Cn+ + C60 (n =58,59,60) collisions following prompt atom knockouts by the fast ions. The statistics from the MD simulations indicate a much higher reactivity of C59+ and C58+ fragments compared to that of C60+. It is found that the covalently bonded dumbbell-shaped fullerene dimers C118+ and C119+ can be formed at very low-collision energies within 1 ps and are stable enough to survive on the microsecond time scale of the experiment. The thermodynamic and kinetic stabilities, as well as the bonding features, have been investigated for the most stable dumbbell dimers C118+, C119+, and C120+.

Wang, Y.; Zettergren, H.; Rousseau, P.; Chen, T.; Gatchell, M.; Stockett, M. H.; Domaracka, A.; Adoui, L.; Huber, B. A.; Cederquist, H.; Alcamí, M.; Martín, F.

2014-06-01

297

The giant lobes of Centaurus A observed at 118 MHz with the Murchison Widefield Array  

NASA Astrophysics Data System (ADS)

We present new wide-field observations of Centaurus A (Cen A) and the surrounding region at 118 MHz with the Murchison Widefield Array (MWA) 32-tile prototype, with which we investigate the spectral-index distribution of Cen A's giant radio lobes. We compare our images to 1.4 GHz maps of Cen A and compute spectral indices using temperature-temperature plots and spectral tomography. We find that the morphologies at 118 MHz and 1.4 GHz match very closely apart from an extra peak in the southern lobe at 118 MHz, which provides tentative evidence for the existence of a southern counterpart to the northern middle lobe of Cen A. Our spatially averaged spectral indices for both the northern and southern lobes are consistent with previous analyses, however we find significant spatial variation of the spectra across the extent of each lobe. Both the spectral-index distribution and the morphology at low radio frequencies support a scenario of multiple outbursts of activity from the central engine. Our results are consistent with inverse-Compton modelling of radio and gamma-ray data that support a value for the lobe age of between 10 and 80 Myr.

McKinley, B.; Briggs, F.; Gaensler, B. M.; Feain, I. J.; Bernardi, G.; Wayth, R. B.; Johnston-Hollitt, M.; Offringa, A. R.; Arcus, W.; Barnes, D. G.; Bowman, J. D.; Bunton, J. D.; Cappallo, R. J.; Corey, B. E.; Deshpande, A. A.; deSouza, L.; Emrich, D.; Goeke, R.; Greenhill, L. J.; Hazelton, B. J.; Herne, D.; Hewitt, J. N.; Kaplan, D. L.; Kasper, J. C.; Kincaid, B. B.; Koenig, R.; Kratzenberg, E.; Lonsdale, C. J.; Lynch, M. J.; McWhirter, S. R.; Mitchell, D. A.; Morales, M. F.; Morgan, E.; Oberoi, D.; Ord, S. M.; Pathikulangara, J.; Prabu, T.; Remillard, R. A.; Rogers, A. E. E.; Roshi, D. A.; Salah, J. E.; Sault, R. J.; Shankar, N. Udaya; Srivani, K. S.; Stevens, J.; Subrahmanyan, R.; Tingay, S. J.; Waterson, M.; Webster, R. L.; Whitney, A. R.; Williams, A.; Williams, C. L.; Wyithe, J. S. B.

2013-12-01

298

Extraction of palladium from acidic solutions with the use of carbon adsorbents  

SciTech Connect

We studied the sorption of palladium(II) on LKAU-4, LKAU-7, and BAU carbon adsorbents from model hydrochloric acid solutions and the solutions of spent palladium-containing catalysts. It was found that sorbents based on charcoal (BAU) and anthracite (LKAU-4) were characterized by high sorption capacities for palladium. The kinetics of the saturation of carbon adsorbents with palladium(II) ions was studied, and it was found that more than 60% of the initial amount of Pd(II) was recovered in a 1-h contact of an adsorbent with a model solution. This value for the solutions of spent catalysts was higher than 35%.

O.N. Kononova; N.G. Goryaeva; N.B. Dostovalova; S.V. Kachin; A.G. Kholmogorov [Krasnoyarsk State University, Krasnoyarsk (Russian Federation)

2007-08-15

299

Optical properties and surface morphology studies of palladium contacts on mercuric iodide single crystals  

NASA Astrophysics Data System (ADS)

Palladium is chemically suitable for electric contacts on mercuric iodide detectors for photon and nuclear radiation detection, so the understanding of palladium contacts is important for fundamental and practical scientific purposes. A study has been conducted on the surface morphology of evaporated contacts using atomic force microscopy (AFM) and optical transmission and reflection. Evaporated palladium coatings are typically nonuniform and may deposit selectively on mercuric iodide surface defects. Reflection measurements show that coating thickness and surface treatment affect intensity, position, and shape of a reflected peak characteristic of the mercuric iodide structure. Results indicate that the band gap energy in the surface of the mercuric iodide is lowered by palladium contacts.

George, M. A.; Azoulay, M.; Burger, A.; Biao, Y.; Silberman, E.; Nason, D.

1993-04-01

300

Tritium release from lithium orthosilicate pebbles deposited with palladium  

NASA Astrophysics Data System (ADS)

Slightly overstoichiometric lithium orthosilicate pebbles are fabricated from lithium hydroxide and silica by a melting and spraying method in a semi-industrial scale facility. The authors performed out-of-pile annealing tests using the lithium orthosilicate pebbles irradiated in a research reactor. Moreover, the effect of the deposition of palladium in the lithium orthosilicate pebbles on the behavior of tritium release was investigated. The lithium orthosilicate pebbles were irradiated in a research reactor. In the out-of-pile annealing experiments, the temperature of lithium orthosilicate pebbles was raised from ambient temperature to 1173 K at a constant rate of 5 K/min under the stream of 0.1% hydrogen/nitrogen sweep gas. The experimental results indicate that almost all tritium was released as tritiated water vapor from the virgin lithium orthosilicate pebbles. It was also found that a lager amount of tritium was released as the molecular form (HT) from the lithium orthosilicate pebbles deposited with palladium.

Munakata, Kenzo; Shinozaki, Takashi; Inoue, Keita; Kajii, Shunsaku; Shinozaki, Yohei; Takeishi, Toshiharu; Knitter, Regina; Bekris, Nicolas; Fujii, Toshiyuki; Yamana, Hajimu; Okuno, Kenji

2009-04-01

301

Tests of isotopic separation efficiency of palladium packed columns  

SciTech Connect

The isotopic effect of palladium has been applied in different ways to separate hydrogen isotopes for many years. At Savannah River Site palladium deposited on kieselguhr (Pd/k) is used in a thermal cycling absorption process (TCAP) to purify tritium for over ten years. The need to design columns for different throughputs and the desire to advance the performance of TCAP created the need to evaluate different column designs and packing materials for their separation efficiency. In this work, columns with variations in length, diameter and metal foam presence were tested using an isotope displacement method. A simple computer model was also developed to calculate the number of theoretical separation stages based on the test results. The effects of column diameter, metal foam presence and gas flow rate were identified. (authors)

Heung, L. K.; Staack, G. C.; Klein, J. E.; Jacobs, W. D. [Savannah River National Laboratory, 773-A, Savannah River Site, Aiken, SC 29808 (United States)

2008-07-15

302

Methane and methanol synthesis over supported palladium catalysts  

SciTech Connect

Hydrogenation of carbon monoxide has been studied between 260 and 340/sup 0/C and 5 and 50 atm of pressure over palladium supported on three different silicas and on HY and NaY zeolites. Fresh and used catalysts were characterized by chemisorption, temperature-programmed desorption, x-ray diffraction, electron microscopy, and photoelectron spectroscopy studies. The selectivity and the activity of the catalysts are strongly dependent on the nature of the support and on the state of the metal on its surface. Methanol is produced on the catalysts exhibiting small size crystallites on which CO is weakly adsorbed, whereas the formation of methane is directly related to the density of acidic sites at the surface of the support. Under the experimental conditions the palladium undergoes structural and electronic modifications due to transformations into hydride phases. These transformations lead to a cracking of the metal crystallites and to changes in the reaction rate expressions. 7 figures, 7 tables.

Fajula, F.; Anthony, R.G.; Lunsford, J.H.

1982-02-01

303

Complete oxidation of methane on palladium catalysts. Final Report  

SciTech Connect

This is the final report for grant DE-FG02-00ER15026. It summarizes all the accomplishments in these 8 sections: (1) Adaptations on Existing Unit and Construction of New Unit; (2) Turnover Rate and Reaction Orders for the Complete Oxidation of Methane on a Palladium Foil in Excess Dioxygen; (3) Surface area increase on Pd foils after oxidation in excess methane; (4) UV Raman spectroscopic study of hydrogen bonding in gibbsite and bayerite between 93 and 453 K; (5) Coverage of Palladium Catalysts by Oxidized Silicon During Complete Oxidation of Methane; (6) Kinetics of Methane Oxidation under lean conditions over Pd and PdO; (7) An Explanation for the Hysteresis on the Oxidation of Methane; and (8) Structure of Pd(111) after oxidation in O{sub 2}.

Ribeiro, Fabio H.

2003-07-17

304

Morphological and functional deterioration of the rat thyroid following chronic exposure to low-dose PCB118.  

PubMed

Polychlorinated biphenyls (PCBs) are persistent environmental pollutants that can severely disrupt the synthesis and secretion of endocrine hormones. To investigate the effects of 2,3',4,4',5-pentachlorobiphenyl (PCB118) on thyroid structure and function, 40 male Wistar rats were divided into 4 equal treatment groups and administered vehicle or one of three doses of PCB118. The experimental groups received intraperitoneal (i.p.) injection of 10, 100, or 1000?g/kg/day PCB118, 5 days per week for 13 weeks, whereas the control group was injected with corn oil (vehicle). Serum concentrations of free thyroxine (FT4), free triiodothyronine (FT3) and thyroid stimulating hormone (TSH) were measured by radioimmunoassays. Histopathological and ultrastructural changes in the thyroid were observed under light microscopy and transmission electron microscopy (TEM). The mRNA expression levels of the sodium-iodide symporter (NIS) and thyroglobulin (TG) were quantified by real-time PCR. Increasing doses of PCB118 resulted in progressively lower FT3, FT4 and TSH concentrations in serum. Injection of PCB118 at all doses led to histopathological deterioration of the thyroid characterized by follicular hyperplasia and expansion, shedding of epithelial cells and fibrinoid necrosis. Follicle cells exhibited swollen or vacuolated endoplasmic reticula, as revealed by TEM. Exposure to PCB118 also caused significant decreases in NIS and TG mRNA expression levels. Chronic exposure to low-dose PCB118 and other PCB congeners may be a significant risk factor for thyroid diseases. PMID:23557935

Tang, Jin-Mei; Li, Wen; Xie, Yu-Chun; Guo, Hong-Wei; Cheng, Pei; Chen, Huan-Huan; Zheng, Xu-Qin; Jiang, Lin; Cui, Dai; Liu, Yun; Ding, Guo-Xian; Duan, Yu

2013-11-01

305

The electrodeposition and electrocatalytic properties of copper–palladium alloys  

Microsoft Academic Search

The codeposition of copper and palladium from solutions of CuSO4 and PdSO4 in 0.6M HClO4 is investigated using microdisc voltammetry. It is shown that good quality coatings of CuPd may be deposited and the composition may be controlled either through the deposition potential or the Cu(II)\\/Pd(II) ratio in solution. While the deposits seem to be amorphous and the copper can

Clelia Milhano; Derek Pletcher

2008-01-01

306

Palladium\\/silicon nanowire Schottky barrier-based hydrogen sensors  

Microsoft Academic Search

This work presents the design, fabrication, and characterization of a hydrogen sensor based on a palladium\\/nanowire Schottky barrier field-effect transistor that operates at room temperature. The fabricated sensor consists of boron-doped silicon nanowire arrays that are contact printed on top of a SiO2\\/Si substrate with subsequently evaporated Pd contacts. The fabrication process is compatible with post-CMOS and plastic substrate integration

Karl Skucha; Zhiyong Fan; Kanghoon Jeon; Ali Javey; Bernhard Boser

2010-01-01

307

Determination of palladium--aluminum reaction propagation rates and temperatures  

Microsoft Academic Search

Three experimental techniques--thermometry, framing and streaking photography, and dynamic radiography--were employed to determine the reaction propagation rates and temperatures of various mixtures of palladium and aluminum. Pellets of 94\\/6, 90\\/10, and 80\\/20 Pd\\/Al mixtures with an average density of 5 x 10³ kg\\/m³ were prepared and tested in an insulating sleeve. Pretest radiography was used to determine the density in

Birnbaum

1978-01-01

308

Palladium-Catalyzed Synthesis of N-Aryl Carbamates  

PubMed Central

An efficient synthesis of aryl carbamates was achieved by introducing alcohols into the reaction of palladium-catalyzed cross-coupling of ArX (X = Cl, OTf) with sodium cyanate. The use of aryl triflates as electrophilic components in this transformation allowed for an expanded substrate scope for direct synthesis of aryl isocyanates. This methodology provides direct access to major carbamate protecting groups, S-thiocarbamates, and diisocyanate precursors to polyurethane materials.

Vinogradova, Ekaterina V.; Park, Nathaniel H.; Fors, Brett P.; Buchwald, Stephen L.

2013-01-01

309

Nanocontact-induced catalytic activation in palladium nanoparticles  

NASA Astrophysics Data System (ADS)

We report the synthesis and catalytic studies of novel palladium nanostructures assembled from small nanoparticles by a surfactant-templated method. These one-dimensional nanomaterials comprise high-density nanocontacts of ~1 nm in contact length at the particle-particle interface. In contrast to dispersed Pd nanoparticles (~5 nm), the polycrystalline palladium nanowires exhibit enhanced (~200 times) catalytic reactivity towards carbon-carbon cross-couplings under mild conditions. Theoretical modeling studies suggest that the presence of nanocontacts triggers electron transfer and localized charge redistribution in the contact region. The charge redistribution causes the nanocontacts to become highly attractive to charged organic molecules, resulting in the facilitation of organic transformations.We report the synthesis and catalytic studies of novel palladium nanostructures assembled from small nanoparticles by a surfactant-templated method. These one-dimensional nanomaterials comprise high-density nanocontacts of ~1 nm in contact length at the particle-particle interface. In contrast to dispersed Pd nanoparticles (~5 nm), the polycrystalline palladium nanowires exhibit enhanced (~200 times) catalytic reactivity towards carbon-carbon cross-couplings under mild conditions. Theoretical modeling studies suggest that the presence of nanocontacts triggers electron transfer and localized charge redistribution in the contact region. The charge redistribution causes the nanocontacts to become highly attractive to charged organic molecules, resulting in the facilitation of organic transformations. Electronic supplementary information (ESI) available: Detailed information on the materials and methods used to fabricate and characterize the Pd nanocontacts and nanowires. See DOI: 10.1039/b9nr00093c

Jiang, Changlong; Ranjit, Sadananda; Duan, Zhongyu; Zhong, Yu Lin; Loh, Kian Ping; Zhang, Chun; Liu, Xiaogang

2009-11-01

310

Monomolecular, nanosized and heterogenized palladium catalysts for the Heck reaction  

Microsoft Academic Search

The review comprises discussion concerning transformations of soluble and insoluble palladium catalysts during the Heck reaction. Special attention is paid to two essential stages of the Heck reaction: reduction of Pd(II) in precursor to Pd(0) and oxidative addition of the main substrate, aryl halide, to Pd(0) in a form of monomolecular or nanosized Pd(0) colloid. It was shown that both,

Anna M. Trzeciak; Józef J. Zió?kowski

2007-01-01

311

Biaryl Phosphine Ligands in Palladium-Catalyzed Amination  

PubMed Central

Palladium-catalyzed amination of aryl halides has undergone rapid development in the last 12 years. This has been largely driven by implementation of new classes of ligands. Biaryl phosphines have proven to provide especially active catalysts in this context. This review discusses the applications that these catalysts have found in C-N cross-coupling in heterocycle synthesis, pharmaceuticals, materials science and natural product synthesis.

Surry, David S.

2012-01-01

312

Telomerization of isoprene with phthalimide at complex palladium catalysts  

SciTech Connect

The telomerization of isoprene with phthalimide takes place smoothly at complex palladium catalysts with the formation of a mixture of N-dimethyloctadienyl-phthalimides, which give a mixture of seven dimethyloctadienylamines when treated with hydrazine. By comparison of the samples of all the mixtures of N-dimethyloctadienyldimethylamines by GLC we established that terpene amines are formed during the telomerization of isoprene with phthalimide followed by cleavage of the mixture of telomers with hydrazine hydrate.

Zakharkin, M.I.; Guseva, V.V.; Sulaimankulova, D.D.; Petrushkina, E.A.

1988-01-10

313

Characteristics of magnetism in nanoporous carbon with palladium clusters  

Microsoft Academic Search

The magnetic properties of samples of nanoporous carbon with palladium clusters prepared from polycrystalline SiC have been\\u000a studied over a wide range of temperatures. The specific magnetic moment rapidly decreases with increasing temperature. The\\u000a obtained experimental magnetization curves have a nonlinear character but do not reach saturation even in a field of 10 kOe.\\u000a Being constructed as functions of H\\/T,

A. M. Danishevskii; T. L. Makarova; A. A. Sitnikova; B. D. Shanina

2011-01-01

314

Determination of palladium in deoxo catalysts by differential pulse voltammetry  

Microsoft Academic Search

A differential pulse voltammetric (DPV) method is proposed for the determination of palladium in deoxo catalysts, which are\\u000a used in recombination units of the cover gas system of nuclear reactors. The electrode system consists of hanging mercury\\u000a drop electrode (HMDE)\\/ platinum auxillary\\/ Ag-AgCl reference electrode. The supporting electrolyte consists of 0.02 M diammonium\\u000a tartrate + 0.08 M ammonia-ammonium chloride buffer

V. T. Aher; M. M. Palrecha; A. V. Kulkarni; G. C. Shah; P. K. Mathur

1999-01-01

315

Methane conversion to syngas in a palladium membrane reactor  

Microsoft Academic Search

Catalytic partial oxidation and dry reforming of methane to syngas have been carried out on Pd\\/Al2O3 between 350–550°C and 550–600°C, respectively. A conventional fixed-bed reactor and a membrane reactor containing dense palladium membrane prepared by electroless-plating were used. The CH4 conversion, and CO and H2 yield were considerably enhanced in the membrane reactor for both processes. CH4 conversion increased between

J Galuszka; R. N Pandey; S Ahmed

1998-01-01

316

Oxidation of methanol over a palladium monolithic automotive catalyst  

Microsoft Academic Search

The oxidation of methanol and its partial oxidation products, carbon monoxide and formaldehyde, were studied using a monolithic catalyst containing palladium. Experimental conditions simulated those in the catalytic converter of a methanol-fueled automobile. With a properly activated catalyst and a fuel-lean feed, carbon dioxide was the only carbon-containing product, and the methanol conversion above the light-off temperature of the catalyst

Kevin A. Frankel; Tyson M. Mew; Phooi K. Lim; George W. Roberts

1996-01-01

317

Methane and methanol synthesis over supported palladium catalysts  

Microsoft Academic Search

Hydrogenation of carbon monoxide has been studied between 260 and 340°C and 5 and 50 atm of pressure over palladium supported on three different silicas and on HY and NaY zeolites. Fresh and used catalysts were characterized by chemisorption, temperature-programmed desorption, x-ray diffraction, electron microscopy, and photoelectron spectroscopy studies. The selectivity and the activity of the catalysts are strongly dependent

F. Fajula; R. G. Anthony; J. H. Lunsford

1982-01-01

318

Effective separation of palladium from simulated high level radioactive waste  

Microsoft Academic Search

Aiming the selective recovery of palladium from high level radioactive liquid waste (HLW), a chelating thiamide type sorbent,\\u000a CWP–TU, was prepared by the modification of Japanese cedar wood powder (CWP). Convection oven and microwave heating were separately\\u000a used for modification purpose and found that microwave heating is more effective over oven heating. CWP–TU was extensively\\u000a studied for the adsorption of

Durga Parajuli; Koichi Hirota; Noriaki Seko

2011-01-01

319

Palladium Nanowire Hydrogen Sensor Based on a SAW Transducer  

Microsoft Academic Search

Palladium (Pd) nano-wires were synthesized by electro chemical deposition technique. Pd nano-wires were transferred onto a ZnO\\/36° LiTaO3 Surface Acoustic Wave (SAW) transducer with an approximate operating frequency of 100 MHz. This operational frequency approximately corresponds to the device's highest conductometric sensitivity. These devices were investigated for hydrogen (H2) sensing at the room temperature. It was observed that the device

Massood Z. Atashbar; Kourosh Kalantar-zadeh; Samual J. Ippolitto

2009-01-01

320

Palladium catalyzed intramolecular acylcyanation of alkenes using ?-iminonitriles.  

PubMed

Reported here is a palladium catalyzed intramolecular acylcyanation of alkenes using ?-iminonitriles. Through this method, highly functionalized indanones are synthesized in moderate to high yields using Pd(PPh3)4, without need for any additional ligands, and a common Lewis acid (ZnCl2). Additionally, the reaction tolerates substitution at various positions on the aromatic ring including electron donating and electron withdrawing groups. PMID:24980625

Rondla, Naveen R; Ogilvie, Jodi M; Pan, Zhongda; Douglas, Christopher J

2014-07-15

321

Thermal Neutron Capture Cross Sections Of The Palladium Isotopes  

Microsoft Academic Search

We have measured precise thermal neutron capture gamma-ray cross sections cry for all stable Palladium isotopes with the guided thermal neutron beam from the Budapest Reactor. The data were compared with other data from the literature and have been evaluated into the Evaluated Gamma-ray Activation File (EGAF). Total radiative neutron capture cross-sections sigmagamma can be deduced from the sum of

R. B. Firestone; M. Krtiáka; D. P. McNabb; B. Sleaford; U. Agvaanluvsan; T. Belgya; Zs. Révay

2006-01-01

322

Thermal Neutron Capture Cross Sections of The Palladium Isotopes  

Microsoft Academic Search

We have measured precise thermal neutron capture γ-ray cross sections Ï{sub γ} for all stable Palladium isotopes with the guided thermal neutron beam from the Budapest Reactor. The data were compared with other data from the literature and have been evaluated into the Evaluated Gamma-ray Activation File (EGAF)[1]. Total radiative neutron capture cross-sections Ïâ can be deduced from the sum

R B Firestone; M Krticka; D P McNabb; B Sleaford; U Agvaanluvsan; T Belgya; Z Revay

2005-01-01

323

Hydrogen Segregation in Crystalline Palladium and Effects on Mechanical Properties  

NASA Astrophysics Data System (ADS)

Calculations of tensile strength and tensile modulus were carried out to investigate the effects of hydrogen interactions, diffusion and segregations in palladium single crystal, high-vacancy crystal and bicrystal, by using the embedded atom method. Elevated temperature, hydrogen absorption and defects such as vacancy and grain boundary (GB) individually induce a loss in mechanical strength of palladium in a monotonous manner. The hydrogen-induced mechanical degradation was noticed at the grain boundary, as well as in bulk. The failure induced by hydrogen in palladium up to xH=0.1 is plastic rather than brittle, even around grain boundary region, by formation of dislocations. At high H absorption, the global hydrogen concentration is a dominant factor over crystal defects. However, a high-angle grain boundary such as ?5 (2 1 0) provides a great driving force for diffusion and tendency for physical trapping of hydrogen. Therefore, the existence of grain boundary makes materials more susceptible and easily exposed to high hydrogen absorption and segregation. Also, our simulation shows that hydrogen maintains the highest localization at GB in the vicinity of ambient temperatures; and this finding coordinates with experimental observation that hydrogen embrittlement are generally observed at room temperatures.

Pham, Hieu; Benzerga, Amine; Cagin, Tahir

2011-03-01

324

Recovery of hydrogen from impurities using a palladium membrane reactor  

SciTech Connect

One of the important steps in processing the exhaust from a fusion reactor is recovering tritium which is incorporated into molecules such as water and methane. One device which may prove to be very effective for this purpose is a palladium membrane reactor. This is a reactor which incorporates a Pd/Ag membrane in the reactor geometry. Reactions such as water gas shift, steam reforming and methane cracking can be carried out over the reactor catalyst, and the product hydrogen can be simultaneously removed from the reacting mixture. Because product is removed, greater than usual conversions can be obtained. In addition ultrapure hydrogen is produced, eliminating the need for an additional processing step. A palladium membrane reactor has been built and tested with three different catalysts. Initial results with a Ni-based catalyst show that it is very effective at promoting all three reactions listed above. Under the proper conditions, hydrogen recoveries approaching 100% have been observed. This study serves to experimentally validate the palladium membrane reactor as potentially important tool for fusion fuel processing.

Willms, R.S. [Los Alamos National Lab., NM (United States); Okuno, K. [Japan Atomic Energy Research Inst., Naka, Ibaraki (Japan)

1993-12-01

325

In situ generation of palladium nanoparticles in smectite clays  

SciTech Connect

A novel synthetic route has been developed for the preparation of clay intercalated palladium catalysts. Liquid sorption and X-ray diffraction measurements on ethanol(1)-toluene(2)/hexadecylammonium montmorillonite dispersions indicated that a toluene-rich bulk liquid phase was equilibrated with a swollen, ethanol-rich interlamellar phase having a volume of about 0.9 cm{sup 3}/g organoclay. Introduction of palladium(II) acetate into the organoclay suspension led to the generation and deposition of a metallic palladium dispersion in the interlamellar space. This system behaved as a versatile nanophase reactor, wherein the ethanol functioned as both solvent and reducing agent. The progress of the Pd{sup 2+} {r_arrow} Pd{sup 0} reaction was monitored spectrophotometrically. The ethanolic reduction afforded Pd particles 2 to 14 nm in diameter, depending on the experimental conditions, deposited on clay particle defect sites. Organoclays loaded up to 10 mass % Pd were synthesized and characterized by BET surface area analysis, transmission electron microscopy, low-shear rheology, X-ray diffraction, and small-angle X-ray scattering measurements. The Pd-organoclay samples proved to be catalytically active in olefin hydrogenation in the liquid phase. 30 refs., 8 figs., 1 tab.

Kiraly, Z.; Dekany, I.; Mastalir, A. [Attila Jozsef Univ., Szeged (Hungary)] [and others] [Attila Jozsef Univ., Szeged (Hungary); and others

1996-06-01

326

Methane ignition catalyzed by in situ generated palladium nanoparticles  

SciTech Connect

Catalytic ignition of methane over the surfaces of freely-suspended and in situ generated palladium nanoparticles was investigated experimentally and numerically. The experiments were conducted in a laminar flow reactor. The palladium precursor was a compound (Pd(THD){sub 2}, THD: 2,2,6,6-tetramethyl-3,5-heptanedione) dissolved in toluene and injected into the flow reactor as a fine aerosol, along with a methane-oxygen-nitrogen mixture. For experimental conditions chosen in this study, non-catalytic, homogeneous ignition was observed at a furnace temperature of {proportional_to}1123 K, whereas ignition of the same mixture with the precursor was found to be {proportional_to}973 K. In situ production of Pd/PdO nanoparticles was confirmed by scanning mobility, transmission electron microscopy and X-ray photoelectron spectroscopy analyses of particles collected at the reactor exit. The catalyst particle size distribution was log-normal. Depending on the precursor loading, the median diameter ranged from 10 to 30 nm. The mechanism behind catalytic ignition was examined using a combined gas-phase and gas-surface reaction model. Simulation results match the experiments closely and suggest that palladium nanocatalyst significantly shortens the ignition delay times of methane-air mixtures over a wide range of conditions. (author)

Shimizu, T.; Abid, A.D.; Poskrebyshev, G.; Wang, H. [Department of Aerospace and Mechanical Engineering, University of Southern California, Los Angeles, CA 90089 (United States); Nabity, J.; Engel, J.; Yu, J. [TDA Research, Inc., 12345 W. 52nd Ave, Wheat Ridge, CO 80033 (United States); Wickham, D. [Reaction Systems, LLC, 19039 E. Plaza Drive, Suite 290, Parker, CO 80134 (United States); Van Devener, B.; Anderson, S.L. [Department of Chemistry, University of Utah, Salt Lake City, UT 84112 (United States); Williams, S. [Air Force Research Laboratory, Mail Stop RZA, 1950 Fifth Street, WPAFB, OH 45433 (United States)

2010-03-15

327

Electrochemical formation of bi-metal (copper–palladium) electrocatalyst supported on poly-3,4-ethylenedioxythiophene  

Microsoft Academic Search

Bi-metal modification of poly-3,4-ethylenedioxythiophene (PEDOT) layers by combining palladium and copper deposition is studied. Initial reference measurements are performed on electrodriven deposition and electroless precipitation of palladium, showing the existence of Pd nanocrystals on the PEDOT surface. It is established that by using the electrodeposition sequence – Cu (first step) – Pd (second step) only palladium remains available in the

M. Ilieva; V. Tsakova; W. Erfurth

2006-01-01

328

A simple one-pot strategy to platinum-palladium@palladium core-shell nanostructures with high electrocatalytic activity  

NASA Astrophysics Data System (ADS)

Well-defined platinum-palladium@palladium core-shell nanospheres (PtPd@Pd NSs) are synthesized by a facile one-pot solution approach using N-methylimidazole and poly(vinyl pyrrolidone) (PVP) as directing and capping agents, respectively, without using any seed, template, or organic solvent. The coexistence of the precursors, N-methylimidazole, PVP, and reaction temperature has great effects on the final morphology. Thus-prepared nanocomposites display an improved electrocatalytic activity for oxygen reduction reaction (ORR) in acidic media, methanol and ethylene glycol oxidation reaction in alkaline media, compared with Pt nanoparticles, Pd nanoparticles, commercial Pt black and Pd black catalysts. This method may direct a general orientation for shape control synthesis of functional bimetallic nanocrystals as promising electrocatalysts in direct alcohol fuel cells (DAFCs).

Lv, Jing-Jing; Zheng, Jie-Ning; Wang, Ying-Ying; Wang, Ai-Jun; Chen, Li-Li; Feng, Jiu-Ju

2014-11-01

329

New Palladium-Catalyzed Approaches to Heterocycles and Carbocycles  

SciTech Connect

The tert-butylimines of o-(1-alkynyl)benzaldehydes and analogous pyridinecarbaldehydes have been cyclized under very mild reaction conditions in the presence of I{sub 2}, ICl, PhSeCl, PhSCl and p-O{sub 2}NC{sub 6}H{sub 4}SCl to give the corresponding halogen-, selenium- and sulfur-containing disubstituted isoquinolines and naphthyridines, respectively. Monosubstituted isoquinolines and naphthyridines have been synthesized by the metal-catalyzed ring closure of these same iminoalkynes. This methodology accommodates a variety of iminoalkynes and affords the anticipated heterocycles in moderate to excellent yields. The Pd(II)-catalyzed cyclization of 2-(1-alkynyl)arylaldimines in the presence of various alkenes provides an efficient way to synthesize a variety of 4-(1-alkenyl)-3-arylisoquinolines in moderate to excellent yields. The introduction of an ortho-methoxy group on the arylaldimine promotes the Pd-catalyzed cyclization and stabilizes the resulting Pd(II) intermediate, improving the yields of the isoquinoline products. Highly substituted naphthalenes have been synthesized by the palladium-catalyzed annulation of a variety of internal alkynes, in which two new carbon-carbon bonds are formed in a single step under relatively mild reaction conditions. This method has also been used to synthesize carbazoles, although a higher reaction temperature is necessary. The process involves arylpalladation of the alkyne, followed by intramolecular Heck olefination and double bond isomerization. This method accommodates a variety of functional groups and affords the anticipated highly substituted naphthalenes and carbazoles in good to excellent yields. Novel palladium migratiodarylation methodology for the synthesis of complex fused polycycles has been developed, in which one or more sequential Pd-catalyzed intramolecular migration processes involving C-H activation are employed. The chemistry works best with electron-rich aromatics, which is in agreement with the idea that these palladium-catalyzed C-H activation reactions parallel electrophilic aromatic substitution. A relatively efficient synthesis of cyclopropanes has been developed using palladium-catalyzed C-H activation chemistry, in which two new carbon-carbon bonds are formed in a single step. This method involves the palladium-catalyzed activation of relatively unreactive C-H bonds, and provides a very efficient way to synthesize cyclopropapyrrolo[1,2-a]indoles, analogues of the mitomycin antibiotics.

Qinhua Huang

2004-12-19

330

Inkjet printing of palladium catalyst patterns on polyimide film for electroless copper plating  

Microsoft Academic Search

A convenient method has been developed that provides for applying patterned copper tracks on flexible polyimide film for electronic applications. The workflow comprises inkjet printing of an aqueous palladium(II) solution onto surface treated polyimide film, followed by reduction to metallic palladium and electroless copper plating. All processing steps involved require minimal infrastructure and result in metallic feature dimensions down to

Stephan Busato; Alberto Belloli; Paolo Ermanni

2007-01-01

331

Palladium-Catalyzed Carbonylation of o-Iodoanilines for Synthesis of Isatoic Anhydrides.  

PubMed

A novel palladium-catalyzed oxidative double carbonylation of o-iodoanilines for the synthesis of isatoic anhydrides has been developed. The reaction employs readily available o-iodoanilines as the starting materials and proceeds under mild conditions. For extension, palladium-catalyzed oxidative carbonylation of anthranilic acids was developed for the synthesis of substituted isatoic anhydrides in high to excellent yields. PMID:24720706

Gao, Sha; Chen, Ming; Zhao, Mi-Na; Du, Wei; Ren, Zhi-Hui; Wang, Yao-Yu; Guan, Zheng-Hui

2014-05-01

332

Palladium-catalyzed substitution of (coumarinyl)methyl acetates with C-, N-, and S-nucleophiles  

PubMed Central

Summary The palladium-catalyzed nucleophilic substitution of (coumarinyl)methyl acetates is described. The reaction proceeds though a palladium ?-benzyl-like complex and allows for many different types of C-, N-, and S-nucleophiles to be regioselectively added to the biologically active coumarin motif. This new method was utilized to prepare a 128-membered library of aminated coumarins for biological screening.

Chattopadhyay, Kalicharan; Fenster, Erik; Grenning, Alexander J

2012-01-01

333

Electrochemical preparation and characterization of electrodes modified with mixed hexacyanoferrates of nickel and palladium  

Microsoft Academic Search

Mixed nickel\\/palladium hexacyanoferrates have been prepared both as thin films and bulk precipitates (powders) attached to electrode surfaces. The mixed material does not seem to be a simple mixture of hexacyanoferrates of nickel and palladium, and it shows unique voltammetric and electrochromic characteristics when compared with the respective single-metal hexacyanoferrates. Electrodeposition of a mixed film is achieved by potential cycling

Pawel J Kulesza; Marcin A Malik; Roman Schmidt; Anna Smolinska; Krzysztof Miecznikowski; Silvia Zamponi; Andrzej Czerwinski; Mario Berrettoni; Roberto Marassi

2000-01-01

334

Experimental study on cold fusion using deuterium gas and deuterium ion beam with palladium  

Microsoft Academic Search

A series of experiments using deuterium gas and low energy deuteron beam with palladium has been designed at Mississippi State University to allow for the observation, if it exists, of cold fusion. Three experiments were performed. One involved the diffusion transient of deuterium gas into palladium. The gas was cooled by liquid nitrogen, and its temperature was permitted to rise

Albert G. Gu; Robert K. F. Teng; Mark S. Miller; Jeff Sprouse

1990-01-01

335

Phase diagrams of thin films of the palladium hydrogen system using a quartz crystal thickness monitor  

Microsoft Academic Search

A technique for obtaining pressure-concentration isotherms of the palladium hydrogen system is described. A quartz crystal thickness monitor is used to directly determine the quantity of hydrogen absorbed by an evaporated palladium film. The measured phase diagrams agree with previous measurements on bulk samples. The method can be applied to any metal film-gas system.

G. A. Frazier; R. Glosser

1979-01-01

336

Highly enantioselective alkenylation of glyoxylate with vinylsilane catalyzed by chiral dicationic palladium(II) complexes.  

PubMed

Chiral dicationic palladium complex-catalyzed vinylation and dienylation of glyoxylate with vinylsilanes and dienylsilanes to produce highly optical active allylic alcohols has been achieved. The advantages of this reaction are that the chiral palladium catalyst is readily employed and that vinylsilanes as nucleophiles are easily synthesized, storable, and air- and moisture-stable. PMID:19788326

Aikawa, Kohsuke; Hioki, Yuta; Mikami, Koichi

2009-10-01

337

Synthesis and Application of Palladium Precatalysts that Accommodate Extremely Bulky di-tert-Butylphosphino Biaryl Ligands  

PubMed Central

A series of palladacyclic precatalysts that incorporate electron-rich di-tert-butylphosphino biaryl ligands is reported. These precatalysts are easily prepared, and their use provides a general means of employing bulky ligands in palladium-catalyzed cross-coupling reactions. The application of these palladium sources to various C-N and C-O bond-forming processes is also described.

Bruno, Nicholas C.

2013-01-01

338

Development of a composite palladium membrane for selective hydrogen separation at high temperature  

Microsoft Academic Search

In this paper a method is described for development of a composite palladium membrane for selective hydrogen separation at high temperature. Electroless plating is used to form a thin palladium film on a silver porous substrate. The composite formed showed excellent mechanical strength and very large selectivity for hydrogen. The studies performed so far suggest that electroless plating can be

Rakesh Govind; Devendra Atnoor

1991-01-01

339

Palladium-catalyzed three-component reaction of N-tosylhydrazone, norbornene and aryl halide.  

PubMed

A palladium-catalyzed three-component reaction of N-tosylhydrazone, norbornene and aryl halide has been demonstrated. In this reaction, an intermolecular Heck-type reaction occurs, which is followed by the alkyl palladium carbene migratory insertion process. This transformation provides an efficient and convenient methodology for the double functionalization of norbornene with good to excellent yields. PMID:24777124

Hu, Fangdong; Xia, Ying; Liu, Zhenxing; Ma, Chen; Zhang, Yan; Wang, Jianbo

2014-06-14

340

Nanoaggregates of a pentacenequinone derivative as reactors for the preparation of palladium nanoparticles.  

PubMed

Fluorescent nanoaggregates of pentacenequinone derivative serve as reactors for the preparation of palladium nanoparticles in aqueous medium. Further, the combination of catalytic quantities of palladium nanoparticles with NaBH(4) smoothly reduces 4-nitrophenol to 4-aminophenol in aqueous medium. PMID:23042509

Bhalla, Vandana; Gupta, Ankush; Kumar, Manoj

2012-12-18

341

Isotope shifts, spins and hyperfine structures of 118,146Cs and of some francium isotopes  

Microsoft Academic Search

High-resolution laser spectroscopy using thermal atomic beams has been performed on-line with the ISOLDE facility at CERN. It allowed the measurement of the spins, isotope shifts and hyperfine structures of the D2 line of 118,146Cs, and that of the hyperfine factors of the first P1\\/2 level of 133,135,137,139,141,143Cs and 210,212,213,221Fr. Previous data concerning 207-213,220-228Fr have also been reanalysed. All results

A. Coc; C. Thibault; F. Touchard; H. T. Duong; P. Juncar; S. Liberman; J. Pinard; M. Carre; J. Lerme; J. L. Vialle; S. Buttgenbach; A. C. Mueller; A. Pesnelle

1987-01-01

342

STS-118 Astronaut Williams and Expedition 15 Engineer Anderson Perform EVA  

NASA Technical Reports Server (NTRS)

As the construction continued on the International Space Station (ISS), STS-118 Astronaut Dave Williams, representing the Canadian Space Agency, participated in the fourth and final session of Extra Vehicular Activity (EVA). During the 5 hour space walk, Williams and Expedition 15 engineer Clay Anderson (out of frame) installed the External Wireless Instrumentation System Antenna, attached a stand for the shuttle robotic arm extension boom, and retrieved the two Materials International Space Station Experiments (MISSE) for return to Earth. MISSE collects information on how different materials weather in the environment of space.

2007-01-01

343

Photoneutron cross sections for 118--124Sn and the ?-ray strength function method  

NASA Astrophysics Data System (ADS)

Photoneutron cross sections were measured for 118Sn, 119Sn, 120Sn, 122Sn, and 124Sn near neutron threshold with quasi-monochromatic laser-Compton scattering ? rays. A systematic analysis of the present photoneutron data and existing neutron-capture data is made using the ?-ray strength function on the basis of the HFB + QRPA model of E1 strength supplemented with a pygmy dipole resonance, which was deduced from a previous study on 116Sn and 117Sn. Radiative neutron capture cross sections for two radioactive nuclei, 121Sn and 123Sn, are deduced through the ?-ray strength function method.

Utsunomiya, H.; Goriely, S.; Kamata, M.; Akimune, H.; Kondo, T.; Itoh, O.; Iwamoto, C.; Yamagata, T.; Toyokawa, H.; Lui, Y.-W.; Harada, H.; Kitatani, F.; Goko, S.; Hilaire, S.; Koning, A. J.

2011-11-01

344

41 CFR 302-12.118 - Under a homesale program, may we establish a maximum home value above which we will not pay for...  

Code of Federal Regulations, 2013 CFR

...which we will not pay for homesale services? 302-12.118 Section 302-12.118 Public Contracts and Property Management Federal...RELOCATION ALLOWANCES RESIDENCE TRANSACTION ALLOWANCES 12-USE OF A RELOCATION SERVICES COMPANY...

2013-07-01

345

41 CFR 102-118.335 - What does the GSA Audit Division consider when verifying an agency prepayment audit program?  

Code of Federal Regulations, 2010 CFR

...verifying an agency prepayment audit program? 102-118.335 Section...verifying an agency prepayment audit program? The GSA Audit Division bases verification of agency prepayment audit programs on objective...

2010-07-01

346

41 CFR 102-118.335 - What does the GSA Audit Division consider when verifying an agency prepayment audit program?  

Code of Federal Regulations, 2010 CFR

...verifying an agency prepayment audit program? 102-118.335 Section...verifying an agency prepayment audit program? The GSA Audit Division bases verification of agency prepayment audit programs on objective...

2009-07-01

347

25 CFR 224.118 - How must the tribe respond to the Director's notice of the opportunity for a hearing?  

Code of Federal Regulations, 2011 CFR

...224.118 Indians BUREAU OF INDIAN AFFAIRS, DEPARTMENT OF THE INTERIOR ENERGY AND MINERALS TRIBAL ENERGY RESOURCE AGREEMENTS UNDER THE INDIAN TRIBAL ENERGY DEVELOPMENT AND SELF DETERMINATION ACT Interested Party Petitions §...

2011-04-01

348

21 CFR 118.11 - Registration requirements for shell egg producers covered by the requirements of this part.  

Code of Federal Regulations, 2010 CFR

...2010-04-01 false Registration requirements for shell egg producers covered by the requirements...PRODUCTION, STORAGE, AND TRANSPORTATION OF SHELL EGGS § 118.11 Registration requirements for shell egg producers covered by the...

2010-04-01

349

17 CFR 1.18 - Records for and relating to financial reporting and monthly computation by futures commission...  

Code of Federal Regulations, 2010 CFR

...Records for and relating to financial reporting and monthly computation...COMMODITY EXCHANGE ACT Minimum Financial and Related Reporting Requirements § 1.18 Records for and relating to financial reporting and monthly...

2010-04-01

350

17 CFR 1.18 - Records for and relating to financial reporting and monthly computation by futures commission...  

Code of Federal Regulations, 2010 CFR

...Records for and relating to financial reporting and monthly computation...COMMODITY EXCHANGE ACT Minimum Financial and Related Reporting Requirements § 1.18 Records for and relating to financial reporting and monthly...

2009-04-01

351

41 CFR 102-118.260 - Must my agency send all quotations, tenders, or contracts with a TSP to GSA?  

Code of Federal Regulations, 2010 CFR

...Must my agency send all quotations, tenders, or contracts with a TSP to GSA...Government Billing Documents Quotations, Tenders Or Contracts § 102-118.260 Must my agency send all quotations, tenders, or contracts with a TSP to...

2010-07-01

352

41 CFR 102-118.260 - Must my agency send all quotations, tenders, or contracts with a TSP to GSA?  

Code of Federal Regulations, 2010 CFR

...Must my agency send all quotations, tenders, or contracts with a TSP to GSA...Government Billing Documents Quotations, Tenders Or Contracts § 102-118.260 Must my agency send all quotations, tenders, or contracts with a TSP to...

2009-07-01

353

Palladium-catalyzed combustion of methane: Simulated gas turbine combustion at atmospheric pressure  

SciTech Connect

Atmospheric pressure tests were performed in which a palladium catalyst ignites and stabilizes the homogeneous combustion of methane. Palladium exhibited a reversible deactivation at temperatures above 750 C, which acted to ``self-regulate`` its operating temperature. A properly treated palladium catalyst could be employed to preheat a methane/air mixture to temperatures required for ignition of gaseous combustion (ca. 800 C) without itself being exposed to the mixture adiabatic flame temperature. The operating temperature of the palladium was found to be relatively insensitive to the methane fuel concentration or catalyst inlet temperature over a wide range of conditions. Thus, palladium is well suited for application in the ignition and stabilization of methane combustion.

Griffin, T.; Weisenstein, W. [ABB Corporate Research Center, Daettwill (Switzerland)] [ABB Corporate Research Center, Daettwill (Switzerland); Scherer, V. [ABB Kraftwerke, Mannheim (Germany)] [ABB Kraftwerke, Mannheim (Germany); Fowles, M. [ICI Katalco, Cleveland (United Kingdom)] [ICI Katalco, Cleveland (United Kingdom)

1995-04-01

354

Effect of calcium modification on the microstructure and oxidation property of submicron spherical palladium powders  

SciTech Connect

Ca-modified spherical palladium particles were prepared from the mixed solution of Pd(NO{sub 3}){sub 2} and Ca(NO{sub 3}){sub 2} by ultrasonic spray pyrolysis. Pure palladium powder and that modified with less than 55 ppm Ca were composed of single crystal particles. However, Ca addition of more than 550 ppm resulted in polycrystalline particles. Crystallite size of the particles decreased with the increase of Ca addition and changed dramatically at the addition of some hundred ppm. Ca additive did not form solid solution with palladium but formed CaPd{sub 3}O{sub 4} on the surface and grain boundary of the particles. 50 ppm{endash}1{percent} of Ca addition significantly reduced the oxidization of palladium powder. More addition of Ca resulted in excess oxidation due to the reaction between palladium and calcium oxide. {copyright} {ital 1997 Materials Research Society.}

Che, S.; Sakurai, O.; Funakubo, H.; Shinozaki, K.; Mizutani, N. [Department of Inorganic Materials, Faculty of Engineering, Tokyo Institute of Technology, 2-12-1, Ookayama, Meguro-ku, Tokyo 152 (Japan)

1997-02-01

355

Palladium-Mediated Surface-Initiated Kumada Catalyst Polycondensation: A Facile Route Towards Oriented Conjugated Polymers.  

PubMed

Palladium-mediated surface-initiated Kumada catalyst transfer polycondensation is used to generate poly(3-methyl thiophene) films with controlled thickness up to 100 nm. The palladium initiator density is measured using cyclic voltammetry and a ferrocene-capping agent, where the surface density is found to be 55% (1.1 × 10(14) molecules per cm(2) ). UV-Vis spectroscopy and AFM show increased aggregation in palladium-initiated films due to the higher grafting density of palladium initiators on the surface. The anisotropy of the P3MT films is determined using polarized UV-Vis spectroscopy, which indicates a degree of orientation perpendicular to the substrate. Evidence that palladium can maintain ?-complexation even at elevated temperatures, is also shown through the exclusive intramolecular coupling of both a phenyl and thiophene-based magnesium bromide with different dihaloarenes. PMID:22968767

Huddleston, N Eric; Sontag, S Kyle; Bilbrey, Jenna A; Sheppard, Gareth R; Locklin, Jason

2012-09-12

356

Mercaptobenzoic acid-palladium(0) complexes as active catalysts for S-benzylation with benzylic alcohols via (?(3)-benzyl)palladium(ii) cations in water.  

PubMed

Mercaptobenzoic acid-palladium(0) complexes show high catalytic activity for S-benzylation with benzylic alcohols via the (?(3)-benzyl)palladium(ii) cation in water. Notably, these palladium(0) complexes could play an important role in formation of active (?(3)-benzyl)palladium(ii) cation complexes followed by S-benzylation. Hammett studies on the rate constants of S-benzylation by various substituted alcohols show good correlation between log(kX/kH) and the ?(+) value of the respective substituents. From the slope, negative ? values are obtained, suggesting that there is a build-up of positive charge in the transition state. Water plays an important role in the catalytic system for sp(3) C-O bond activation and stabilization of the activated Pd(ii) cation species. The catalytic system can be performed using only 2.5 mol% Pd2(dba)3 without the phosphine ligand or other additives. PMID:24986042

Hikawa, Hidemasa; Azumaya, Isao

2014-07-16

357

COST-EFFECTIVE METHOD FOR PRODUCING SELF SUPPORTED PALLADIUM ALLOY MEMBRANES FOR USE IN EFFICIENT PRODUCTION OF COAL DERIVED HYDROGEN  

SciTech Connect

Competed fabrication of an initial series of copper and palladium-copper alloy membranes in the range of 1-8 microns in thickness up to 6 inch x 8 inch in area. Films were produced using both e-beam evaporation (with and without ion assist) and magnetron sputtering from a 60%Pd/40%Cu alloy target. Pure copper and palladium-copper alloy films, with essential no intrinsic stress, were produced on both polystyrene and polyvinyl alcohol substrates. Various processing parameters and techniques were investigated in order to minimize defects and maximize uniformity in single layer films. Even though films to date are visually defect free, we are able to observe sub-micron size defects using a backlighting technique; we are currently investigating a number of methods to create a gas impermeable membrane. At present, the metal films are effectively removed from the polymer backing material by merely immersing the film in an appropriate solvent; chloroform for the polystyrene and water for the PVA. In the future we plan to investigate alternative methods for removing the polymer backing that are more suited to large scale, low-cost manufacturing.

B. Lanning; J. Arps

2004-01-01

358

TL-118 and Gemcitabine Drug Combination Display Therapeutic Efficacy in a MYCN Amplified Orthotopic Neuroblastoma Murine Model - Evaluation by MRI  

PubMed Central

Neuroblastoma (NB) is the most common extra-cranial pediatric solid tumor with up to 50% of NB patients classified as having high-risk disease with poor long-term survival rates. The poor clinical outcome and aggressiveness of high-risk NB strongly correlates with enhanced angiogenesis, suggesting anti-angiogenic agents as attractive additions to the currently insufficient therapeutics. TL-118, a novel drug combination has been recently developed to inhibit tumor angiogenesis. In the current study, we used the SK-N-BE (2) cell line to generate orthotopic NB tumors in order to study the combinational therapeutic potential of TL-118 with either Gemcitabine (40 mg/kg; IP) or Retinoic acid (40 mg/kg; IP). We show that TL-118 treatment (n?=?9) significantly inhibited tumor growth, increased cell apoptosis, reduced proliferation and extended mouse survival. Moreover, the reciprocal effect of TL-118 and Gemcitabine treatment (n?=?10) demonstrated improved anti-tumor activity. The synergistic effect of these drugs in combination was more effective than either TL or Gemcitabine alone (n?=?9), via significantly reduced cell proliferation (p<0.005), increased apoptosis (p<0.05) and significantly prolonged survival (2-fold; p<0.00001). To conclude, we demonstrate that the novel drug combination TL-118 has the ability to suppress the growth of an aggressive NB tumor. The promising results with TL-118 in this aggressive animal model may imply that this drug combination has therapeutic potential in the clinical setting.

Komar-Stossel, Chani; Gross, Eitan; Dery, Elia; Corchia, Nathalie; Meir, Karen; Fried, Iris; Abramovitch, Rinat

2014-01-01

359

Detection and complete genome characterization of human enterovirus 118 from children with acute respiratory disease in China.  

PubMed

Enterovirus 118 (EV-118) within species HEV-C was detected in two 5-month-old boys with pneumonia in China. The EV-118 from both cases was genetically closer to ISR10 strain from Israel than to PER161 strain from Peru based on VP1 gene sequences. The complete genome of the detected EV-118 consists of 7,360 nucleotides, excluding the poly (A) tail. The 5'UTR contains 669 nucleotides, and 3'UTR consists of 73 nucleotides. A single open reading frame from base 670 to 7,287 that encodes a 2,206-amino-acid polyprotein was featured. The base composition of the full genome is 27.9 % A, 24.2 % C, 24.4 % G, and 23.6 % U. Phylogenetic analysis of the full genome sequences illustrated EV-118 was genetically closer to EV-109 and EV-105, and the Chinese strain differed from Peru strain. In summary, the presence of EV-118 was confirmed in pediatric pneumonia cases and complete genome sequences were identified for the first time in China. PMID:24557729

Lu, Qing-Bin; Wo, Ying; Wang, Hong-Yu; Zhang, Xiao-Ai; Huang, Dou-Dou; Zhao, Jin; Liu, En-Mei; Liu, Wei; Cao, Wu-Chun

2014-06-01

360

? decay chains from Z = 118 superheavy nuclei in the range 271 ?A? 310  

NASA Astrophysics Data System (ADS)

An extensive investigation on the ? decay properties of the isotopes of the superheavy nuclei with Z = 118, within the range 271 ?A? 310, has been performed within the Coulomb and proximity potential model for deformed nuclei. The ? decay half-lives of 118294 and its decay products, evaluated using our formalisms, are in good agreement with the experimental results. The calculated ? half-lives were also found to be matching well with the values computed using the Viola-Seaborg systematic, the universal curve of Poenaru et al. [Phys. Rev. C 83, 014601 (2011), 10.1103/PhysRevC.83.014601;Phys. Rev. C 85, 034615 (2012), 10.1103/PhysRevC.85.034615] and the analytical formulas of Royer [J. Phys. G: Nucl. Part. Phys. 26, 1149 (2000), 10.1088/0954-3899/26/8/305]. So as to identify the mode of decay of these isotopes, the spontaneous-fission half-lives were also evaluated for all the isotopes under study and, our prediction of 3? chains from 118294 go hand in hand with the experimental observations. Our study also unveils that those isotopes of Z = 118 with A ? 301 and with A ? 275 do not survive fission, thus restricting the ? decay within the range of 276 ?A? 300, and we hope that the theoretical prediction of 5? decay chains consistently from 118289-293 isotopes provides a new perspective to experimentalists.

Santhosh, K. P.; Priyanka, B.

2014-06-01

361

A rapid and simple route for the synthesis of lead and palladium nanoparticles in tetrazolium based ionic liquid  

NASA Astrophysics Data System (ADS)

In the present work, we report a novel method for the synthesis of palladium and lead nanoparticles by the reduction method in tetrazolium ring based ionic liquid. Palladium and lead nanoparticles so-prepared were well characterized by powder X-ray diffraction measurements (pXRD), transmission electron microscopy (TEM) and quasi elastic light scattering (QELS) techniques. Powder X-ray diffraction (pXRD) analysis revealed all relevant Bragg's reflection for crystal structure of palladium and lead. Powder X-ray diffraction plots also revealed no oxidized material of palladium and lead nanoparticles. TEM showed nearly uniform distribution of the particles in methanol and confirmed by QELS. Typical applications of palladium nanoparticles include in vitro use and sensor design applications. Palladium nanoparticles is also ideal for spin coating, self-assembly and monolayer formation. Palladium nanoparticles can also be considered as potential new catalysts.

Singh, Prashant; Kumar, Pradeep; Kumari, Kamlesh; Sharma, Pankaj; Mozumdar, Subho; Chandra, Ramesh

2011-02-01

362

Detecting Airborne Mercury by Use of Palladium Chloride  

NASA Technical Reports Server (NTRS)

Palladium chloride films have been found to be useful as alternatives to the gold films heretofore used to detect airborne elemental mercury at concentrations of the order of parts per billion (ppb). Somewhat more specifically, when suitably prepared palladium chloride films are exposed to parts-per-billion or larger concentrations of airborne mercury, their electrical resistances change by amounts large enough to be easily measurable. Because airborne mercury adversely affects health, it is desirable to be able to detect it with high sensitivity, especially in enclosed environments in which there is a risk of leakage of mercury from lamps or other equipment. The detection of mercury by use of gold films involves the formation of gold/mercury amalgam. Gold films offer adequate sensitivity for detection of airborne mercury and could easily be integrated into an electronic-nose system designed to operate in the temperature range of 23 to 28 C. Unfortunately, in order to regenerate a gold-film mercury sensor, one must heat it to a temperature of 200 C for several minutes in clean flowing air. In preparation for an experiment to demonstrate the present sensor concept, palladium chloride was deposited from an aqueous solution onto sets of gold electrodes and sintered in air to form a film. Then while using the gold electrodes to measure the electrical resistance of the films, the films were exposed, at a temperature of 25 C, to humidified air containing mercury at various concentrations from 0 to 35 ppb (see figure). The results of this and other experiments have been interpreted as signifying that sensors of this type can detect mercury in room-temperature air at concentrations of at least 2.5 ppb and can readily be regenerated at temperatures <40 C.

Ryan, Margaret; Shevade, Abhijit; Kisor, Adam; Homer, Margie; Jewell, April; Manatt, Kenneth; Torres, Julia; Soler, Jessica; Taylor, Charles

2009-01-01

363

Bulk synthesis of nanoporous palladium and platinum powders  

DOEpatents

Disclosed is a method for providing nanoporous palladium and platinum powders. These materials were synthesized on milligram to gram scales by chemical reduction of tetrahalo-complexes with ascorbate in a concentrated aqueous surfactant at temperatures between -20.degree. C. and 30.degree. C. The prepared particles have diameters of approximately 50 nm, wherein each particle is perforated by pores having diameters of approximately 3 nm, as determined by electron tomography. These materials are of potential value for hydrogen and electrical charge storage applications.

Robinson, David B. (Fremont, CA); Fares, Stephen J. (Pleasanton, CA); Tran, Kim L. (Livermore, CA); Langham, Mary E. (Pleasanton, CA)

2012-04-17

364

Ultralow-power hydrogen sensing with single palladium nanowires  

NASA Astrophysics Data System (ADS)

Palladium nanowires were fabricated on silicon substrates using conventional microfabrication techniques. Sensors based on such nanowires show a reversible response to hydrogen concentrations as low as 27 ppm with response times varying from 5 s (H2 concentrations >20%) to 30 s (H2 concentrations <100 ppm) at room temperature. The response times can be reduced by increasing the applied bias due to resistive heating. The noise spectrum of the nanowires shows a 1/f behavior, sufficiently low to enables the detection of hydrogen with an ultralow-power consumption. The influence of oxygen on the nanowire response was also investigated.

Offermans, P.; Tong, H. D.; van Rijn, C. J. M.; Merken, P.; Brongersma, S. H.; Crego-Calama, M.

2009-06-01

365

The transition in hydrogen sensing behavior in noncontinuous palladium films  

NASA Astrophysics Data System (ADS)

The morphological transition in ultrathin palladium (Pd) films around the percolation threshold and the related transition in hydrogen sensing behavior is investigated. We find that besides the transition from continuous to discontinuous Pd, an intermediate - semicontinuous-state must be considered. It shows hydrogen sensing features of both continuous and discontinuous film types, simultaneously. This study focuses on the discontinuous-semicontinuous transition. Experimental evidence is supported by studying the evolution of the electrical resistance with temperature, under hydrogen exposure and after thermal annealing. The results are highly relevant for the optimization of nanogap based hydrogen sensors.

Kiefer, Thomas; Villanueva, Luis Guillermo; Fargier, Frédéric; Favier, Frédéric; Brugger, Jürgen

2010-09-01

366

Synthesis of Dihydrobenzofurans via Palladium-Catalyzed Heteroannulations  

SciTech Connect

Palladium-catalyzed heteroannulation of 1,3-dienes with 3-iodo-2-alkenols, and 2-iodo-2-alkenols, as well as their amino analogs, affords the corresponding cyclic ethers and amines respectively. The presence of a {beta}-hydrogen in the vinylic halide results in {beta}-hydride elimination giving the corresponding alkyne. The presence of a bulky group in the {alpha}-position of the vinylic halide results in failure or reduced amounts of annulation products. A chloride source, pyridine base and electron-rich phosphine are essential for this reaction.

Roman Vladimirovich Rozhkov

2004-12-19

367

Palladium nanoparticles on InP for hydrogen detection  

PubMed Central

Layers of palladium (Pd) nanoparticles on indium phosphide (InP) were prepared by electrophoretic deposition from the colloid solution of Pd nanoparticles. Layers prepared by an opposite polarity of deposition showed different physical and morphological properties. Particles in solution are separated and, after deposition onto the InP surface, they form small aggregates. The size of the aggregates is dependent on the time of deposition. If the aggregates are small, the layer has no lateral conductance. Forward and reverse I-V characteristics showed a high rectification ratio with a high Schottky barrier height. The response of the structure on the presence of hydrogen was monitored.

2011-01-01

368

Palladium(0)-catalyzed intramolecular decarboxylative allylation of ortho nitrobenzoic esters.  

PubMed

A Pd/Ag bimetallic system has been developed for the decarboxylative allylation of ortho-nitrobenzoic esters in an intramolecular fashion. In contrast to the typical sp(2)-sp(3) cross-coupling approach which requires air and moisture sensitive preformed organometallic reagents, we provide an alternative route to the synthesis of ortho-allyl nitroarenes from the corresponding ortho-nitrobenzoic acid derivatives. The reaction proceeds through a mechanistically distinct decarboxylative metalation pathway. A cooperative reactivity of palladium and silver is crucial for the reaction outcome. PMID:25055344

Hossian, Asik; Singha, Shantanu; Jana, Ranjan

2014-08-01

369

Ozone sensing based on palladium decorated carbon nanotubes.  

PubMed

Multiwall carbon nanotubes (MWCNTs) were easily and efficiently decorated with Pd nanoparticles through a vapor-phase impregnation-decomposition method starting from palladium acetylacetonates. The sensor device consisted on a film of sensitive material (MWCNTs-Pd) deposited by drop coating on platinum interdigitated electrodes on a SiO? substrate. The sensor exhibited a resistance change to ozone (O?) with a response time of 60 s at different temperatures and the capability of detecting concentrations up to 20 ppb. The sensor shows the best response when exposed to O3 at 120 °C. The device shows a very reproducible sensor performance, with high repeatability, full recovery and efficient response. PMID:24736133

Colindres, Selene Capula; Aguir, Khalifa; Cervantes Sodi, Felipe; Vargas, Luis Villa; Salazar, José Moncayo; Febles, Vicente Garibay

2014-01-01

370

Palladium- and nickel-catalyzed alkenylation of enolates.  

PubMed

Transition-metal-catalyzed alkenylation of enolates provides a direct method to synthesize broadly useful ?,?-unsaturated carbonyl compounds from the corresponding carbonyl compound and alkenyl halides. Despite being reported in the early seventies, this reaction class saw little development for many years. In the past decade, however, efforts to develop this reaction further have increased considerably, and many research groups have reported efficient coupling protocols, including enantioselective versions. These reactions most commonly employ palladium catalysts, but there are also some important reports using nickel. There are many examples of this powerful transformation being used in the synthesis of complex natural products. PMID:23325616

Ankner, Tobias; Cosner, Casey C; Helquist, Paul

2013-02-01

371

Ab initio calculations of superconductivity in palladium under pressure  

NASA Astrophysics Data System (ADS)

We have calculated the phonon dispersion and the electron-phonon interaction in palladium at ambient and under pressure using ab initio methods and evaluated superconducting transition temperature on the basis of the BCS theory. At ambient pressure, we have evaluated the electron-phonon coupling constant to be ?=0.377 by the use of the density-functional perturbation theory, and estimated the spin fluctuation effect in relation to the experimental data of specific heat. The vanishing of the superconducting transition at ambient pressure is resulted from the spin fluctuation effect. The spin fluctuation effect reduces with increasing pressure, and the superconductivity appears under pressure.

Takezawa, Tomoki; Nagara, Hitose; Suzuki, Naoshi

2005-01-01

372

Determination of palladium and platinum by atomic absorption  

USGS Publications Warehouse

Palladium and platinum are determined by atomic absorption after fire-assay concentration into a gold bead. The limit of determination is ~0??06 ppm in a 20-g sample. Serious depressive interelement interferences are removed by buffering the solutions with a mixture of cadmium and copper sulphates with cadmium and copper concentrations each at 0??5%. Substantial amounts of Ag, Al, Au, Bi, Ca, Co, Cr, Fe, Hg, K, La, Mg, Mn, Mo, Na, Ni, Pb, Te, Ti, V, Y, Zn, and the platinum metals do not interfere in the atomic-absorption determination. ?? 1969.

Schnepfe, M. M.; Grimaldi, F. S.

1969-01-01

373

Ozone Sensing Based on Palladium Decorated Carbon Nanotubes  

PubMed Central

Multiwall carbon nanotubes (MWCNTs) were easily and efficiently decorated with Pd nanoparticles through a vapor-phase impregnation-decomposition method starting from palladium acetylacetonates. The sensor device consisted on a film of sensitive material (MWCNTs-Pd) deposited by drop coating on platinum interdigitated electrodes on a SiO2 substrate. The sensor exhibited a resistance change to ozone (O3) with a response time of 60 s at different temperatures and the capability of detecting concentrations up to 20 ppb. The sensor shows the best response when exposed to O3 at 120 °C. The device shows a very reproducible sensor performance, with high repeatability, full recovery and efficient response.

Colindres, Selene Capula; Aguir, Khalifa; Sodi, Felipe Cervantes; Vargas, Luis Villa; Moncayo Salazar, Jose A.; Febles, Vicente Garibay

2014-01-01

374

Oxygen-promoted c?h bond activation at palladium.  

PubMed

[Pd(P(Ar)(tBu)2 )2 ] (1, Ar=naphthyl) reacts with molecular oxygen to form Pd(II) hydroxide dimers in which the naphthyl ring is cyclometalated and one equivalent of phosphine per palladium atom is released. This reaction involves the cleavage of both C?H and O?O bonds, two transformations central to catalytic aerobic oxidizations of hydrocarbons. Observations at low temperature suggest the initial formation of a superoxo complex, which then generates a peroxo complex prior to the C?H activation step. A transition state for energetically viable C?H activation across a Pd?peroxo bond was located computationally. PMID:24817523

Scheuermann, Margaret L; Boyce, David W; Grice, Kyle A; Kaminsky, Werner; Stoll, Stefan; Tolman, William B; Swang, Ole; Goldberg, Karen I

2014-06-16

375

Palladium-catalyzed carbonylation of aryl tosylates and mesylates.  

PubMed

A general protocol for the palladium-catalyzed carbonylation of aryl tosylates and mesylates to form esters has been developed using a catalyst system derived from Pd(OAc)2 and the bulky, bidentate dcpp ligand. The system operates under mild conditions: atmospheric CO pressure and temperatures of 80-110 degrees C. A broad substrate scope has been demonstrated allowing carbonylation of electron-rich, electron-poor, and heterocyclic tosylates and mesylates, and the reaction shows wide functional group tolerance. PMID:18257577

Munday, Rachel H; Martinelli, Joseph R; Buchwald, Stephen L

2008-03-01

376

Palladium(II)-catalyzed direct intermolecular alkenylation of chromones.  

PubMed

A new efficient method for the direct alkenylation of chromones via a palladium(II)-catalyzed C-H functionalization reaction was developed. The use of pivalic acid with Cu(OAc)(3)/Ag(2)CO(3) provided superior reactivity in the cross-coupling of chromones with alkene partners. This approach represents a significant advance over the existing two-step method and afforded various 3-vinylchromone derivatives, which are privileged structures in many biologically active compounds and versatile synthetic building blocks. PMID:21797199

Kim, Donghee; Hong, Sungwoo

2011-08-19

377

The study of palladium ions incorporation into the mesoporous ordered silicates  

NASA Astrophysics Data System (ADS)

In this work mesoporous ordered silica materials containing palladium species were prepared using of tetraammine palladium chloride ([Pd(NH3)4]Cl2) complex as a palladium source during synthesis and by wetness impregnation of pure support by solution containing dissolved metal salt. The ammonia ligands from tetraammine palladium chloride were removed during calcination or during thermal treatment at 300 °C in oxygen atmosphere. For reduction of palladium ions to metallic state as prepared materials were treated by hydrogen at high temperature. In this work the locations of palladium atoms in silica lattice were considered by study of binding energy changes of cardinal atoms of mesoporous ordered silica. Ordered mesoporous silicates (MCM-41 and SBA-15) are very promising materials for a wide range of industrial applications due to their unique properties as well-defined ordered structure and excellent textural properties. They exhibit high surface area with high pore volume. Such supports ensure a high dispersion of the metal nanoparticles or other active phases providing the high activity of solid catalysts. The obtained materials were characterized primarily by X-ray diffraction (XRD) technique, X-ray photoelectron spectroscopy (XPS), nitrogen adsorption-desorption isotherms, and infrared spectroscopy. The proportional content of palladium was controlled by X-ray fluorescence technique.

Zienkiewicz-Strza?ka, M.; Pikus, S.

2012-11-01

378

Recovery of palladium from an industrial wastewater using liquid surfactant membranes  

SciTech Connect

Selective recovery of palladium from an industrial wastewater including a large amount of iron was studied by liquid surfactant membranes (LSMs) prepared with a sulfur-containing extractant as a carrier in a stirred cell. The extraction behavior of palladium and iron ions in liquid-liquid extraction was also investigated in order to choose an appropriate carrier for the LSM operations. Palladium ions were found to be extracted selectively over iron ions by using the sulfur-containing extractant from an acidic aqueous solution. The effects of several chemical species and operation factors on the recovery of palladium by LSMs were systematically examined with several kinds of sulfur-containing carriers and thiourea as a stripping reagent. The selection of carrier is a key factor for designing an efficient recovery process of palladium with an LSM technique. Di-2-ethylexyl monothiophosphoric acid (commercial name MSP-8) appears to be one of the best carriers currently available for palladium recovery using the LSM technique. Recovery of more than 95% palladium from a pseudoindustrial wastewater could be attained in a few minutes under optimum conditions.

Kakoe, T.; Horinouchi, N; Goto, M.; Nakashio, F. [Kyushu Univ., Hakozaki, Fukuoka (Japan)

1996-02-01

379

Vapor space characterization of waste Tank 241-TX-118 (in situ): Results from samples collected on 9/7/94  

SciTech Connect

This report describes inorganic and organic analyses results from in situ samples obtained from the headspace of the Hanford waste storage Tank 241-TX-118 (referred to as Tank TX-118). The results described here were obtained to support safety and toxicological evaluations. A summary of the results for inorganic and organic analytes is listed in Table 1. Detailed descriptions of the results appear in the text. Quantitative results were obtained for the inorganic compounds ammonia (NH{sub 3}), nitrogen dioxide (NO{sub 2}), nitric oxide (NO), hydrogen cyanide (CHN), and water (H{sub 2}O). Sampling for sulfur oxides (SO{sub x}) was not requested. In addition, quantitative results were obtained for the 39 TO-14 compounds plus an additional 13 analytes. Hexane, normally included in the additional analytes, was removed because a calibration standard was not available during analysis of Tank TX-118 SUMMA{trademark} canisters. Of these, 12 were observed above the 5-ppbv reporting cutoff. Fourteen tentatively identified compounds (TICs) were observed above the reporting cutoff of (ca.) 10 ppbv and are reported with concentrations that are semiquantitative estimates based on internal-standard response factors. The 10 organic analytes with the highest estimated concentrations are listed in Table 1 and account for approximately 86% of the total organic components in Tank TX-118. Permanent gas analysis was not conducted on the tank-headspace samples. Tank TX-118 is on both the Ferrocyanide and Organic Watch List.

Thomas, B.L.; Clauss, T.W.; Ligotke, M.W.; Pool, K.H.; McVeety, B.D.; Olsen, K.B.; Fruchter, J.S.; Goheen, S.C.

1995-10-01

380

Involvement of an R2R3-MYB transcription factor gene AtMYB118 in embryogenesis in Arabidopsis.  

PubMed

MYB transcription factors play important roles in various developmental processes in plants. Here we report the characterization of AtMYB118, a gene encoding a putative R2R3-type MYB transcription factor, which expresses predominantly in siliques. Real-time quantitative PCR analysis and in situ hybridization showed that the transcripts of AtMYB118 were mainly detected in developing embryos. Constitutive over-expression of AtMYB118 resulted in pleiotropic phenotypes, including dwarfism, compact rosettes, backward curly-leaves, smaller flowers and siliques, and premature seed dehydration at the tip of siliques. Microarray analysis showed that many genes encoding proteins accumulated during embryogenesis were remarkably up-regulated in AtMYB118-over-expressed transgenic plants, including late embryogenesis abundant proteins (LEA proteins), storage proteins, seed maturation proteins, and proteins related with seed dehydration, desiccation and ABA signaling pathway. These results suggest that AtMYB118 may play an important role during embryogenesis and seed maturation. PMID:19066902

Zhang, Yunfei; Cao, Guangyu; Qu, Li-Jia; Gu, Hongya

2009-03-01

381

Meteor Beliefs Project: The Palladium in ancient and early Medieval sources  

NASA Astrophysics Data System (ADS)

An examination of the, apparently meteoritic, object, anciently called the Palladium after the Greek goddess Pallas Athene, is presented, as discussed in various ancient and early medieval sources. Although made of wood, the Palladium was believed to have fallen from the sky. In myths, it was a powerful totemic object, first at the legendary city of Troy, then later at Rome, and had magically protective properties associated with it. Despite its implausibly meteoritic nature, the Palladium can be suggested as supporting the case for ancient meteorite worship.

McBeath, A. Alistair; Gheorghe, A. D.

2004-08-01

382

Behavior of palladium-copper catalysts for CO and NO elimination  

SciTech Connect

The behavior of a series of palladium and palladium-copper catalysts supported on ceria/alumina for the CO + NO + O{sub 2} reaction has been analyzed by a combination of electron transmission microscopy, infrared, and electron paramagnetic spectroscopies and catalytic test studies. In both systems, the catalytic behavior is dominated by the properties of the metal-ceria interface. The addition of copper to a palladium system leads to beneficial effects related to alloy formation in which both CO and NO elimination are enhanced. The chemical consequences and catalytic implications of Pd-Cu alloying are discussed.

Fernandez-Garcia, M.; Martinez-Arias, A.; Belver, C.; Anderson, J.A.; Conesa, J.C.; Soria, J.

2000-03-10

383

Zinc-mediated palladium-catalyzed formation of carbon-sulfur bonds.  

PubMed

A catalytic amount of zinc chloride in combination with a palladium catalyst ligated by a monodentate phosphine allows the coupling of aryl and alkyl thiols with aryl bromides in high yields. The addition of zinc chloride to a palladium catalyst system that reportedly failed to promote sulfide formation allows this once ineffective catalyst system to provide the sulfide product in good yield. This paper describes a high-yielding and general monodentate phosphine-ligated palladium catalyst for biaryl and alkyl aryl sulfide formation. PMID:19344165

Eichman, Chad C; Stambuli, James P

2009-05-15

384

Chitosan microspheres supported palladium heterogeneous catalysts modified with pearl shell powders.  

PubMed

Significant enhancement of the catalytic stability and activity was obtained for the heterogeneous palladium catalyst supported on the shell powders-reinforced chitosan microspheres. For example, over 90% cross-coupling yields were achieved using as low as 0.05 mol% palladium catalyst loading for the Heck-type reaction of iodobenzene with n-butyl acrylate. Such significant enhancement of the catalytic stability and activity can be attributed to the intermolecular interactions of the surface polar molecules of the incorporated shell powders with the surrounding chitosan molecules as well as the deposited palladium species. PMID:23376558

Zeng, Minfeng; Qi, Chenze; Zhang, Xian-man

2013-04-01

385

Stopping power of palladium for protons in the energy range 0.300-3.100 MeV  

NASA Astrophysics Data System (ADS)

The stopping power of palladium for protons has been measured using the transmission method with an overall uncertainty of around 5% over the energy range Ep=(0.300-3.100) MeV. These stopping power data are then compared to stopping power values calculated by the SRIM-2010 code and to those derived from a model based on the dielectric formalism. Subsequently, and within the framework of the modified Bethe-Bloch theory, this stopping power data were used for extracting Pd target mean excitation and ionization potential, (I = 468 ± 5 eV), and Barkas effect parameter, (b = 1.51 ± 0.06). A good agreement is found between the obtained results and values reported in literature.

Miranda, P. A.; Sepúlveda, A.; Morales, J. R.; Rodriguez, T.; Burgos, E.; Fernández, H.

2014-01-01

386

Investigation of mass transfer surface self-diffusion on palladium  

NASA Astrophysics Data System (ADS)

Growth of voids in thin palladium layers (8-20 nm) on alumina and silica substrates has been investigated by Auger electron spectroscopy and atomic force microscopy. Using the Brandon-Bradshaw's model, based on capillarity forces, the surface self-diffusion coefficients of palladium have been evaluated in the temperature range of 583-823 K. We have found that the results are independent of the substrate, in agreement with the assumption that the growth of voids is controlled by surface self-diffusion on the metal. The mass transfer surface self-diffusion coefficients are expressed by D s ( m2/ s)=1.1×10 -7exp[-97±13 ( kJ/mol) /RT] . These new results are compared with literature data. The experimental and theoretical values for intrinsic diffusion coefficients on oriented surfaces disclose much lower activation energies than that found in the present work, and the differences are related to the formation energy of the defects responsible for surface diffusion.

Beszeda, I.; Gontier-Moya, E. G.; Beke, D. L.

2003-12-01

387

Mechanism of catalytic hydrogenation of but-1-yne on palladium  

SciTech Connect

The deuteration mechanism of but-1-yne on differently dispersed Pd/Al{sub 2}O{sub 3} catalysts (D = 26%, >80%) was studied at 293 K. Experiments were performed by flowing a hydrocarbon square pulse at constant pressure (15 Torr) and a H{sub 2}-He carrier gas (37-708 Torr) onto the catalyst. Three stages were observed, namely (i) an initial stage with high activity and very low selectivity; the duration of this stage was proportional to the palladium weight and the number of hydrocarbon molecules which passed through the catalyst; (ii) a steady-state stage with constant activity and 98% but-1-ene selectivity; using microwave spectroscopy the authors found that in addition to the cis addition of two deuterium atoms, 10 to 20% of but-1-ene were produced by a different route; (iii) a final stage in which, when the hydrocarbon pressure decreased in the gas phase, an additional desorption peak was obtained consisting of C{sub 4} hydrocarbons. It is proposed that the palladium surface during the steady state is covered by strongly but reversibly adsorbed but-1-yne molecules which act as a poison and are in equilibrium with the reactive chemisorbed but-1-yne molecules. The reactive molecules are described as vinylic adsorbed species in equilibrium with carbene and carbyne species. The first lead to a cis addition mechanism. The latter two lead to the trans addition and direct hydrogenation.

Hub, S.; Touroude, R. (Universite Louis Pasteur, Strasbourg (France))

1988-12-01

388

Low Temperature Hydrogen Transport Using Palladium/Copper Membrane  

SciTech Connect

Results are presented from low temperature hydrogen permeation experiments using a palladium/copper membrane. Inlet pressure was varied from 5 psig to 180 psig, while temperature was varied from 25°C to 275°C. The palladium/copper membranes exhibited flow stability problems at low temperatures and pressures when using ultra high purity hydrogen. A preconditioning step of high temperatures and inlet pressures of pure hydrogen was necessary to stimulate any substantial permeate flows. After pre-conditioning, results showed zero hydrogen flow when using 3–4% hydrogen mixed with helium or argon. It is thought that the inert gas atoms were adsorbed into the membrane surface and thus blocked the hydrogen atom dissolution. When using pure hydrogen at low to moderate temperatures and low pressures, no measurable permeate flow was observed. Also, zero permeate flow was observed at relatively high temperatures (e.g., 150°C) and a low inlet pressure (5 psig). The cause of the zero permeate flow, when using pure hydrogen, was attributed to interface control of the permeation process. Interface control could be due to: (a) insufficient energy to split the hydrogen molecule into hydrogen atoms, or (b) a reversible phase change from beta to alpha of crystals at the near surface.

Lessing, Paul Alan; Wood, Henry Carwin; Zuck, Larry Douglas

2003-06-01

389

Polynuclear palladium complexes with biogenic polyamines: AFM and voltammetric characterization.  

PubMed

Polynuclear Pd(II) complexes with biogenic polyamines present great potential clinical importance, due to their antiproliferative and cytotoxic activity coupled to less severe side-effects. The adsorption process and the redox behaviour of two polynuclear palladium chelates with spermine (Spm) and spermidine (Spd), Pd(II)-Spm and Pd(II)-Spd, as well as of their ligands Spm and Spd, were studied using atomic force microscopy (AFM) and voltammetry at highly oriented pyrolytic graphite and glassy carbon electrodes. AFM revealed different adsorption patterns and degree of surface coverage, correlated with the chelate structure, concentration of the solution, applied potential and voltammetric behaviour of the Spm, Spd, Pd(II)-Spm and Pd(II)-Spd systems. The voltammetric study of Spm and Spd showed that these biogenic polyamines undergo an irreversible and pH-dependent oxidation. In acid medium the polyamines are fully protonated, rendering their oxidation more difficult. With increasing pH the oxidation potential for both Spm and Spd is shifted to less positive values, indicating a greater ease of oxidation in alkaline medium. The Pd(II)-Spm and Pd(II)-Spd complexes dissociate at high negative or high positive potentials. The application of a positive potential induced the oxidation of these Pd complexes and the formation of mixed layers of palladium oxides, Spm/Spd and Pd(II)-Spm/Pd(II)-Spd. PMID:19766544

Corduneanu, O; Chiorcea-Paquim, A-M; Fiuza, S M; Marques, M P M; Oliveira-Brett, A M

2010-06-01

390

Fibre optics in palladium-based hydrogen sensing  

NASA Astrophysics Data System (ADS)

Hydrogen sensing at low concentrations in the order of tens to hundreds of parts per million (ppm) over extended periods requires highly sensitive and stable sensor technology. Palladium and its alloys are widely used in hydrogen sensing as they show a high and selective affinity for hydrogen. On exposure to hydrogen, Pd experiences a volumetric expansion, roughly proportional to the hydrogen concentration in the environment. This volumetric expansion can be measured either directly by dimensional monitoring or through monitoring of secondary physical effects. Optical sensor technology is a preferred technique for hydrogen sensing because of its inherent safety for use in a potentially explosive environment, and several optical hydrogen sensors have been reported. However, the majority have been designed to measure hydrogen concentrations of a few per cent in air, whereas the sensors described here are capable of operating in concentrations down to hundreds of ppm. Fibre Bragg gratings (FBGs) and interferometric length monitoring are shown to be able to monitor the dimensions of a palladium sensor element. Hydrogenation not only induces physical strain but also changes the electronic configuration resulting in a change in refractive index which can be monitored using a long-period grating (LPG). The paper discusses the respective characteristics of these different optical measurement techniques using Pd and Pd/Ag alloys as sensor elements for hydrogen concentrations between 100 ppm and 1%.

Maier, R. R. J.; Jones, B. J. S.; Barton, J. S.; McCulloch, S.; Allsop, T.; Jones, J. D. C.; Bennion, I.

2007-06-01

391

Anomalous Nernst and Hall effects in magnetized platinum and palladium  

NASA Astrophysics Data System (ADS)

We study the anomalous Nernst effect (ANE) and anomalous Hall effect (AHE) in proximity-induced ferromagnetic palladium and platinum which is widely used in spintronics, within the Berry phase formalism based on the relativistic band-structure calculations. We find that both the anomalous Hall (?xyA) and Nernst (?xyA) conductivities can be related to the spin Hall conductivity (?xyS) and band exchange splitting (?ex) by relations ?xyA=?exe??xyS(EF)' and ?xyA=-?23kB2T?ex??xys(? )'', respectively. In particular, these relations would predict that the ?xyA in the magnetized Pt (Pd) would be positive (negative) since the ?xyS(EF)' is positive (negative). Furthermore, both ?xyA and ?xyA are approximately proportional to the induced spin magnetic moment (ms) because the ?ex is a linear function of ms. Using the reported ms in the magnetized Pt and Pd, we predict that the intrinsic anomalous Nernst conductivity (ANC) in the magnetic platinum and palladium would be gigantic, being up to ten times larger than, e.g., iron, while the intrinsic anomalous Hall conductivity (AHC) would also be significant.

Guo, G. Y.; Niu, Q.; Nagaosa, N.

2014-06-01

392

Rapid Responding Palladium-Silver Surface Modified Microsensor for Hydrogen  

SciTech Connect

Most palladium thin film based hydrogen gas sensors have response and recovery times that are too long to make them useful in vehicular and stationary gas leak detection applications. In contrast, a palladium-silver thin film based microcantilever (MC) hydrogen gas microsensor is reported herein with near ideal response characteristics for use in these hydrogen economy related applications. Specifically, 3-10 second response and recovery times have been measured for these sensors in contrast to previous sensor response measurements of several to tens of minutes using Pd thin film and MC based sensing techniques. The much reduced response times observed in the present study are attributed to a wet chemical Pd-Ag thin film deposition technique and a gas conditioning protocol that produces a highly nanostructured, porous film that rapidly adsorbs and desorbs H2, allowing rapid equilibration with the H2 concentration in the surrounding air. The wet chemical process and gas phase conditioning offer a novel approach at creating highly structured surfaces that have not been reported for MC devices. Additionally, these sensors have very low H2 detection thresholds, wide dynamic range and very good selectivity relative to common interferents.

Patton, James [ORNL; Hunter, Scott Robert [ORNL; Sepaniak, Michael [University of Tennessee, Knoxville (UTK); Datskos, Panos G [ORNL; Smith, Barton [ORNL

2010-01-01

393

Palladium-bacterial cellulose membranes for fuel cells.  

PubMed

Bacterial cellulose is a versatile renewable biomaterial that can be used as a hydrophilic matrix for the incorporation of metals into thin, flexible, thermally stable membranes. In contrast to plant cellulose, we found it catalyzed the deposition of metals within its structure to generate a finely divided homogeneous catalyst layer. Experimental data suggested that bacterial cellulose possessed reducing groups capable of initiating the precipitation of palladium, gold, and silver from aqueous solution. Since the bacterial cellulose contained water equivalent to at least 200 times the dry weight of the cellulose, it was dried to a thin membranous structure suitable for the construction of membrane electrode assemblies (MEAs). Results of our study with palladium-cellulose showed that it was capable of catalyzing the generation of hydrogen when incubated with sodium dithionite and generated an electrical current from hydrogen in an MEA containing native cellulose as the polyelectrolyte membrane (PEM). Advantages of using native and metallized bacterial cellulose membranes in an MEA over other PEMs such as Nafion 117 include its higher thermal stability to 130 degrees C and lower gas crossover. PMID:12713915

Evans, Barbara R; O'Neill, Hugh M; Malyvanh, Valerie P; Lee, Ida; Woodward, Jonathan

2003-07-01

394

Fast-neutron scattering from vibrational palladium nuclei  

SciTech Connect

Neutron total cross sections of elemental palladium are measured from {approx}0.6--4.5 MeV. These results, combined with others previously reported from this laboratory, provide a detailed knowledge of the neutron total cross sections of palladium from {approx}0.1--20 MeV. Differential neutron elastic-scattering cross sections are measured from {approx}1.5--10 MeV in sufficient energy and angle detail to well define the energy-average behavior. Concurrently, neutron inelastic-scattering cross sections are measured from {approx}1.5--8 MeV. Inelastically-scattered neutron groups are observed corresponding to excitations of: 306 {+-} 14, 411 {+-} 47, {approx}494, 791 {+-} 20, 924 {+-} 20, 1,156 {+-} 24, 1,358 {+-} 35, 1,554 {+-} 47 and 1,706 {+-} 59 keV, with additional tentative groups at 1,938 and 2,059 keV. Particular attention is given to the inelastic excitation of the 2{sup +} yrast states of the even isotopes. This broad data base is examined in the context of optical-statistical and coupled-channels models. The resulting model parameters are consistent with systematic trends in this vibrational mass region previously noted at this laboratory, and provide a suitable vehicle for many applications.

Smith, A.B. [Argonne National Lab., IL (United States)]|[Univ. of Arizona, Tucson, AZ (United States); Guenther, P.T. [Argonne National Lab., IL (United States)

1993-10-01

395

Synthetic strategies for controlling inter- and intramolecular interactions: Applications in single-molecule fluorescence imaging, bioluminescence imaging, and palladium catalysis  

NASA Astrophysics Data System (ADS)

The field of synthetic organic chemistry has reached such maturity that, with sufficient effort and resources, the synthesis of virtually any small molecule which exhibits reasonable stability at room temperature can be realized. While representing a monumental achievement for the field, the ability to exert precise control over molecular structure is just a means to an end, and it is frequently the responsibility of the synthetic chemist to determine which molecules should actually be synthesized. For better or worse, there exists no competitive free market in academia for new molecules, and as a result, the decision of which compounds should be synthesized is seldom driven by the forces of supply and demand; rather, it is guided by the synthetic chemist's interest in an anticipated structure-function relationship or in the properties of a previously unstudied class of molecules. As a consequence, there exists a pervasive need for chemists with synthetic expertise in fields (e.g., molecular imaging) and subdisciplines of chemistry (e.g., physical chemistry) in which the identification of promising synthetic targets dramatically outpaces the synthetic output in that field or subdiscipline, and ample opportunities are available for synthetic chemists who choose to pursue such cross-disciplinary research. This thesis describes synthetic efforts that leverage these opportunities to realize applications in biological imaging and in palladium catalysis. In Part I, the synthesis and characterization of three novel luminophores and their imaging applications are discussed. The first is a molecular beacon that utilizes a fluorophorefluorophore pair which exhibits H-dimer quenching in the closed conformation. This probe offers several advantages over conventional fluorophore-quencher molecular beacons in the detection of oligonucleotides, both in bulk and at the single-molecule level. Secondly, a fluorescent, Cy3-Cy5 covalent heterodimer is reported, which on account of the proximity of the Cy3 and Cy5 fluorophores, behaves as an optical photoswitch in the presence of a thiol reagent. This unique property was employed to achieve sub-diffraction-limited imaging of the stalks of Caulobacter crescentus cells with 30-nm resolution using STORM (stochastic optical reconstruction microscopy). Lastly, the synthesis of the first selenium analogue of firefly luciferin is described, and this analogue is shown to be a competent substrate for firefly luciferase (fLuc). Remarkably, it exhibits red-shifted bioluminescence emission relative to the native sulfur analogue. The in vivo performance of the selenium and sulfur analogues in imaging are compared by tail-vein injection into nude mice bearing subcutaneous tumor xenografts of a human breast cancer cell line that was stably transduced to express fLuc. Part II of this thesis begins by addressing design considerations in the development of palladium catalysts that effect oxidative transformations under mild conditions (i.e., 1 atm air, room temperature) using molecular oxygen as the terminal oxidant. A newly synthesized cationic palladium complex, [(2,9-dimethylphenanthroline)Pd(OAc)]2[OTf]2, is shown to catalyze aerobic alcohol oxidation under such conditions with an unprecedented initial turnover frequency, but the presence of partially reduced oxygen species results in competitive ligand oxidation with concomitant decrease in catalyst activity. To remedy this, oxidatively resistant ligands, which are essential for the development of next-generation, high-turnover-frequency palladium catalysts that utilize oxygen as a terminal oxidant, have been prepared and effectively employed. In addition, the first general palladium-catalyzed route to the carbonylation of diols is reported. In this system, carbon monoxide (1 atm) serves the carbonyl source, (2,9-dimethylphenanthroline)Pd(OAc) 2 acts as the catalyst, and N-chlorosuccinimide and iodosobenzene are the oxidants for 1,2- and 1,3-diols, respectively. This thesis illustrates the power of synthetic organic chemistry to exert precise control ove

Conley, Nicholas R.

396

Solvent extraction of palladium(II) with a Schiff base and separation of palladium from Pd(II)-Pt(VI) mixture  

SciTech Connect

A new Schiff base extractant, N,N{prime}-bis[1-phenyl-3-methyl-5-hydroxy-pyrazole-4-benzylidenyl]-1,3-propylene diamine (H{sub 2}A) was synthesized and characterized. The extraction mechanism of palladium(II) from HNO{sub 3} or HCIO{sub 2} medium with H{sub 2}A in chloroform or toluene was investigated. The influences of the Schiff base concentration in the organic phase, the concentration of palladium, the pH and anions (Cl{sup {minus}}, SO{sub 4}{sup =}, NO{sub 3}{sup {minus}}, ClO{sub 4}{sup {minus}}) in the aqueous phase and the temperature on the distribution ration for palladium (II) have been examined. The extracted complex has been confirmed by chemical analysis, thermoanalyses and IR spectroscopy. It was found that palladium is extracted according to the following extraction reaction: Pd(H{sub 2}O){sub 2}Cl{sub 2(a)} + H{sub 2}A{sub (o)} == Pd(HA)Cl{sub (o)}+H{sup +}{sub (a)} + Cl{sup {minus}}{sub (a)} + 2H{sub 2}O. The extraction equilibrium constants of palladium(II) were 8.4 and 21.3 in chloroform and toluene diluents, respectively. The values for the enthalpy and standard free energy of extraction were also obtained. The separation of Pd(II) from the mixed solution of Pd(II)-Pt(IV) was achieved by adjusting the pH.

Ouyang, J.M.

1999-09-01

397

Effect of Hydrogen Concentration on Superconductivity and Clustering in Palladium Hydride.  

National Technical Information Service (NTIS)

A method of preparing superconducting palladium hydride by electrolysis is described. The relationship of the superconducting transition temperature to hydrogen concentration and the behavior of the hydrogen clustering temperature at high concentrations a...

J. M. E. Harper

1974-01-01

398

Palladium in Non-Aqueous Solvents. Formation, Stability, and Film Forming Properties.  

National Technical Information Service (NTIS)

Palladium atoms in cold acetone, ethanol, and other organic solvents cluster to form living colloidal particles. The Pd colloids are stable for months at room temperature in acetone, and their particle sizes (about 8 nm) vary slightly according to solvent...

G. Cardenas-Trivino K. J. Klabunde B. Dale

1987-01-01

399

Synthesis of mesoporous platinum-palladium alloy films by electrochemical plating in aqueous surfactant solutions.  

PubMed

Mesoporous platinum-palladium alloy films with different compositional ratios have been successfully synthesized by electrochemical plating in aqueous surfactant solutions. Scanning electron micrographs and transmission electron micrographs reveal that all of the platinum-palladium alloy films possess uniform mesopores with a narrow size distribution (around 7 nm). The alloy compositions in the pore walls can be controlled by changing the compositional ratios in the precursor solutions, as confirmed by inductively coupled plasma mass spectroscopy analysis and X-ray photoelectron spectroscopy measurements. Due to large surface areas, the prepared mesoporous platinum-palladium films show distinctly enhanced electrocatalytic activity for methanol oxidation reactions, compared with the commercially available platinum black catalyst. Furthermore, compared with mesoporous platinum film, the alloying of platinum with palladium has a critical effect on the enhanced electrocatalytic activity. In particular, a mesoporous Pt(82)-Pd(18) film exhibits highly enhanced electrocatalytic activity. PMID:22733608

Wang, Hongjing; Yamauchi, Yusuke

2012-09-01

400

Facile and selective copper–palladium catalyzed addition of terminal alkynes to activated alkynes in water  

Microsoft Academic Search

The combination of palladium and copper catalyzes the addition of terminal alkynes to electron-deficient alkynes selectively and effectively in water without the competition of terminal alkynes’ homo-coupling.

Liang Chen; Chao-Jun Li

2004-01-01

401

The Palladium Assisted Transfer Reduction of ?, ?-Unsaturated Nitroalkenes to Oximes Using Ammonium Formate  

Microsoft Academic Search

?, ?-Unsaturated nitroalkenes are readily reduced to the corresponding oximes in good yields using ammonium formate in the presence of palladium. The reactions occur rapidly at room temperature in a solvent system of methanol and tetrahydrofuran.

George W. Kabalka; R. David Pace; P. P. Wadgaonkar

1990-01-01

402

The palladium assisted transfer reduction of. alpha. ,. beta. -unsaturated nitroalkenes to oximes using ammonium formate  

SciTech Connect

{alpha},{beta}-Unsaturated nitroalkenes are readily reduced to the corresponding oximes in good yields using ammonium formate in the presence of palladium. The reactions occur rapidly at room temperature in a solvent system of methanol and tetrahydrofuran.

Kabalka, G.W.; Pace, R.D.; Wadgaonkar, P.P. (Univ. of Tennessee, Knoxville (United States))

1990-01-01

403

Synthesis of fluorinated allenes via palladium-catalyzed monofluoromethylation using FBSM.  

PubMed

Palladium-catalyzed monofluoromethylation of substituted 2-bromo-1,3-dienes using fluorobis(phenylsulfonyl)methane (FBSM) as a pronucleophile gave previously unknown monofluoromethylated allenes in high yields, which are the isosteres of biologically attractive allenic alcohols. PMID:20024230

Ogasawara, Masamichi; Murakami, Hidetoshi; Furukawa, Tatsuya; Takahashi, Tamotsu; Shibata, Norio

2009-12-21

404

[Structural studies of veneered palladium alloys with a focus on the ceramometal interface].  

PubMed

Samples of palladium-silver and palladium-copper alloys with ceramic veneers were examined under incident light and scanning electron microscopes in terms of their metallographic properties. Both materials showed a fine grain structure. The palladium-silver alloy had inhomogeneous crystallites. The palladium-copper alloy showed several heterogeneous phases. Wavelength dispersive x-ray analysis was used to record concentration profiles and element distribution patterns. An accumulation of nonprecious components and oxygen was observed in the immediate ceramometal interface. Adjacent to this a largely homogeneous zone was visible which is probably due to the diffusion of nonprecious elements during the different stages of baking. The results lead to conclusions concerning the final finishing after application of the ceramic veneer. PMID:2702159

Walter, M

1989-04-01

405

Enantioselective Palladium-Catalyzed [3+2] Cycloadditions of Trimethylenemethane with Nitroalkenes  

PubMed Central

Nitroalkenes readily undergo palladium-catalyzed [3+2] cycloaddition with trimethylenemethane to generate nitrocyclopentanes in excellent yield and enantioselectivity. Furthermore, the products thus formed are highly versatile synthetic intermediates and provide convenient access to both cyclopentylamines and cyclopentenones.

Trost, Barry M.; Bringley, Dustin A.; Seng, Pamela S.

2012-01-01

406

Study of the kinetics of catalytic decomposition of hydrazine vapors on palladium  

NASA Technical Reports Server (NTRS)

The decomposition rates of N2H4 on a palladium surface are studied. Experiments were conducted in a circulating unit at atmosphere pressure. The experimental method is described. The laws found for the reaction kinetics are explained by equations.

Khomenko, A. A.; Apelbaum, L. O.

1987-01-01

407

PALLADIUM-CATALYZED OXIDATION OF STYRENE AND ALKENES IN PRESENCE OF IONIC LIQUIDS (WACKER REACTION)  

EPA Science Inventory

The use of ionic liquids in various synthetic transformations is gaining significance due to the enhanced reaction rates, potential for recycling and compatibility with various organic compounds and organometallic catalysts. Palladium-catalyzed oxidation of styrene and other alk...

408

Platinum-ruthenium-palladium alloys for use as a fuel cell catalyst  

DOEpatents

A noble metal alloy composition for a fuel cell catalyst, a ternary alloy composition containing platinum, ruthenium and palladium. The alloy shows increased activity as compared to well-known catalysts.

Gorer, Alexander (Sunnyvale, CA)

2002-01-01

409

PALLADIUM CATALYZED COUPLING OF ARYL HALIDES WITH ARYLHALOSILANES IN AIR AND WATER. (R828129)  

EPA Science Inventory

In the presence of a palladium catalyst, various aryl halides reacted with arylhalosilanes in aqueous media and under an air atmosphere to give the corresponding unsymmetrical aryl–aryl coupling products conveniently. ...

410

Palladium-Catalyzed Ortho-Alkoxylation of 2-Aryl-1,2,3-triazoles.  

PubMed

Palladium-catalyzed alkoxylation of 2-aryl-1,2,3-triazoles was described in the presence of various groups in the aromatic rings. In addition, some other directing groups of heterocycles containing nitrogen were explored. PMID:24915142

Shi, Suping; Kuang, Chunxiang

2014-07-01

411

Surface characterization of copper electroless deposition on atomic layer deposited palladium on iridium and tungsten  

Microsoft Academic Search

Iridium and tungsten refractory metals possess high melting points, hardness, and good electrical resistivity. Palladium has been recently deposited on W and Ir via atomic layer deposition and it is also an appropriate catalyst for the electroless deposition of copper. Palladium was deposited at 80±5 °C with a PdII(hfac)2 sublimation temperature of 46.0±0.5 °C using 13 sccm Ar as a

Young-Soon Kim; Jiho Shin; Joong-Hee Cho; Gregory A. Ten Eyck; De-Li Liu; Samuk Pimanpang; Toh-Ming Lu; Jay J. Senkevich; Hyung-Shik Shin

2006-01-01

412

Separation of 111Ag from neutron irradiated natural palladium using alumina as an adsorbent  

Microsoft Academic Search

A simple method is presented for the separation of no-carrier-added 111Ag from neutron irradiated natural palladium. The method is based on sorption of 111Ag in 0.01 M HCl on alumina. Palladium is removed by washing with 0.1 M HCl and the 111Ag is eluted with 4 M HCl. The overall yields of 111Ag are better than 85% with <1 ?g\\/ml

M Khalid; A Mushtaq; M. Z Iqbal

2000-01-01

413

Palladium Enolate Umpolung: Cyclative Diacetoxylation of Alkynyl Cyclohexadienones Promoted by a Pd/SPRIX Catalyst.  

PubMed

A novel palladium-catalyzed reaction involving an unusual nucleophilic attack on a palladium enolate was developed using a spiro-bis(isoxazoline) (SPRIX) ligand. Treatment of alkynyl cyclohexadienone substrates with a Pd/SPRIX catalyst in acetic acid under an oxygen atmosphere furnished diacetoxylated benzofuranone derivatives in good yields. This cyclative diacetoxylation proceeded enantioselectively in the presence of an optically pure SPRIX ligand. PMID:24677411

Takenaka, Kazuhiro; Mohanta, Suman C; Sasai, Hiroaki

2014-04-25

414

Analysis of optical properties of fullerene-palladium nanostructures using effective medium theory  

NASA Astrophysics Data System (ADS)

In this paper an influence of the content of palladium on optical properties of fullerene-palladium nanocomposite was discussed, based on Effective Medium Theory (EMT). Since the complex refractive index of Pd is clearly different from the refractive index of fullerene, even a small admixture of metal leads to significant changes in value of effective index and consequently to change the reflection coefficient of the layer.

Belka, Rados?aw

2013-10-01

415

Dense palladium nanoparticle arrays with controlled coverage for fast hydrogen sensors  

Microsoft Academic Search

We report the application of dense palladium nanoparticle arrays for room-temperature hydrogen sensor with sub-second response time. The palladium nanoparticle arrays were fabricated in between a pair of interdigital electrodes by means of gas phase cluster beam deposition. The coverage of the nanoparticles was controlled by in-situ monitoring the conductance between the electrodes. We demonstrate that the conductance of the

Bo Xie; Linlin Liu; Yue Zhang; Xing Peng; Qian Xu; Mengyang Zheng; Fengqi Song; Guanghou Wang; Min Han; Toshio Takiya

2011-01-01

416

Evaluation of high-temperature distortion of high-palladium metal-ceramic crowns  

Microsoft Academic Search

Statement of problem. Crown fit is a prerequisite for long-term clinical success; however, crown distortion may occur during porcelain firing. The dimensional stability of some high-palladium alloys at high temperatures has been questioned. Purpose. The purpose of this study was to use a new method to measure the distortion of copings for metal-ceramic single units of selected high-palladium alloys with

Efstratios Papazoglou; William A. Brantley; William M. Johnston

2001-01-01

417

Stereoselective synthesis of 2,5-disubstituted morpholines using a palladium-catalyzed hydroamination reaction.  

PubMed

A palladium-catalyzed hydroamination reaction is the key step in a stereoselective synthesis of 2,5-disubstituted and 2,3,5-trisubsituted morpholines from carbamate-protected aziridines. Aziridines are selectively attacked at the more substituted position by unsaturated alcohol nucleophiles using Lewis acid catalysts. Palladium-catalyzed hydroamination of the resulting aminoalkenes gives morpholines as a single diastereomer in excellent yield. PMID:23784260

McGhee, Alicia; Cochran, Brian M; Stenmark, Torrey A; Michael, Forrest E

2013-08-01

418

Structured polyphenylenes as carriers of palladium nanoparticles used as selective hydrogenation catalysts  

Microsoft Academic Search

Structured polyphenylenes that are used as matrices for immobilization of palladium nanoparticles are synthesized through\\u000a the cyclocondensation of acetylaromatic compounds followed by structuring at different temperatures and, as a result, different\\u000a crosslink densities. The relationship between the structure and structuring temperature of the polymers is investigated. It\\u000a is shown that the sizes of palladium nanoparticles immobilized in polyphenylene matrices depend

D. A. Rud’; L. Zh. Nikoshvili; T. P. Loginova; A. V. Naumkin; Yu. L. Slovokhotov; V. G. Matveeva; M. G. Sul’man; I. A. Khotina

2010-01-01

419

Synthesis and characterization of palladium containing membranes based upon polyacrylic acid  

Microsoft Academic Search

Different methods are described to synthesize a highly porous polymer membrane with fine dispersed metal-nanoparticles. The preparation of the porous catalytic membranes happens by crosslinking of polyacrylic acid dispersions with bifunctional crosslinker in presence of palladium particles. Palladium-nanoparticles, stabilized with the block copolymer polystyrene-block-polyethyleneoxide, can be immobilized in the polymer network in different ways. The polymer\\/metal network can be prepared

Andreas Beyer; Reinhard Schomäcker; Karl-Heinz Reichert

2003-01-01

420

Producing a Radioactive Source in a Deuterated Palladium Electrode Under Direct-Current Glow Discharge  

SciTech Connect

Anomalous gamma emission was rarely observed during direct-current glow discharge in {approx}3 Torrs of deuterium gas using a deuterated palladium foil cathode. Autoradiography after the discharge experiment showed that isotopes with low- and high-energy radiation components were produced before or during the discharge. The palladium foil after the anomalous gamma-ray emission was analyzed by secondary ion mass spectroscopy, which revealed a considerable increase in the content of iron and copper on the surface.

Yamada, Hiroshi; Uchiyama, Kazuyoshi; Kawata, Nobuhiko; Kurisawa, Yoshiyuki; Nakamura, Mitsuru

2001-03-15

421

Effects of copper and palladium on the reduction of bromate by Fe(0)  

Microsoft Academic Search

Bromate reduction by Fe(0) with incorporation of copper or palladium was investigated in batch tests. The incorporation of copper led to an increase in the rate of bromate reduction, while incorporation of palladium did not show any effect on bromate reduction by Fe(0), regardless of the bimetal application techniques (either simultaneous addition of Cu(II) or Pd(IV) into the Fe–BrO3- reaction

Li Xie; Chii Shang

2006-01-01

422

Catalytic activity of copper and palladium based catalysts for toluene total oxidation  

Microsoft Academic Search

In this study, catalysts containing 0.5wt.% of palladium or 5wt.% of copper were compared towards toluene total oxidation using FAU Zeolite and ZrO2 supports. A 0.5%Pd\\/NaFAU and 5%Cu\\/ZrO2 were found to be promising catalysts for this reaction. Palladium presented then a better affinity for FAU zeolite and copper oxide had a better affinity for zirconia. The performances of Pd based

H. L. Tidahy; S. Siffert; F. Wyrwalski; J.-F. Lamonier; A. Aboukaïs

2007-01-01

423

A copper-free palladium catalyzed cross coupling reaction of vinyl tosylates with terminal acetylenes  

Microsoft Academic Search

A copper-free palladium-catalyzed cross coupling of vinyl tosylate (2) and terminal acetylenes was investigated, affording a convenient and efficient method for construction of an sp–sp2 carbon?carbon bond. The tosylate (2) derived from 1,3-cyclohexanedione was reacted with terminal acetylene under the copper-free conditions at ambient temperature, in the presence of palladium acetate and triphenylphosphine, to provide the conjugated en-yn-one products in

Xiaoyong Fu; Shuyi Zhang; Jianguo Yin; Doris P. Schumacher

2002-01-01

424

Transfer hydrogenation using recyclable polyurea-encapsulated palladium: efficient and chemoselective reduction of aryl ketones.  

PubMed

A robust and recyclable palladium catalyst [Pd0EnCat] has been prepared by ligand exchange of polyurea-encapsulated palladium(II) acetate with formic acid, resulting in deposition of Pd(0) in the support material; Pd0EnCat is shown to be a highly efficient transfer hydrogenation catalyst for chemoselective reduction of a wide range of aryl ketones to benzyl alcohols. PMID:12703769

Yu, Jin-Quan; Wu, Hai-Chen; Ramarao, Chandrashekar; Spencer, Jonathan B; Ley, Steven V

2003-03-21

425

Modification effects of magnetic supports and bimetallic structures on palladium nanocluster catalysts  

Microsoft Academic Search

Palladium (Pd) and palladium–platinum (Pd–Pt) colloidal nanoclusters catalysts have been prepared and immobilized on a magnetic support. Modification effects of magnetic support Fe3O4 and bimetallic structure on the catalysts have been studied by catalytic experiments and computational simulation. The Fe3O4 support benefits to catalytic selectivity of the nanoclusters in the selective hydrogenation of o-chloronitrobenzene to o-chloroaniline. X-ray photoelectron spectroscopy analyses

Weixia Tu; Shengjun Cao; Liping Yang; Wenchuan Wang

2008-01-01

426

Evaluation of Nickel\\/Palladium\\/Gold-Finished Surface-Mount Integrated Circuits  

Microsoft Academic Search

Texas Instruments has introduced a refined version of its nickel\\/palladium (NiPd) finish for integrated circuit (IC) package leads. The enhanced version of lead finish is nickel\\/palladium\\/gold (NiPdAu). TI has a long and successful history with the NiPd finish. There are more than 40-billion devices in the field with TI NiPd-finished leads. TI introduced the NiPd finish in 1989 and many

Douglas Romm; Bernhard Lange; Donald Abbott

427

A new method for dispersing palladium microparticles in conducting polymer films and its application to biosensors  

Microsoft Academic Search

Composite films of polypyrrole\\/sulfated poly(?-hydroxyethers) (PPy\\/S-PHE) are electrically conducting and mechanically flexible. Palladium particles were dispersed in the films by thermally decomposing bis(dibenzylideneacetone)palladium(0) complex which had been absorbed by the films from a CHCl3 solution. This method for loading metal particles was enabled by the high affinity of the composite films for organic compounds. Transmission electron microscopy (TEM) and energy-dispersive

Hitoshi Yamato; Takafumi Koshiba; Masaki Ohwa; Wolfgang Wernet; Michio Matsumura

1997-01-01

428

Evidences for associated heat generation and nuclear products release in palladium heavy-water electrolysis  

Microsoft Academic Search

Summary  In a galvanostatic experiment of charging deuterium in a palladium cathode, nuclear and thermal effects were found. A sintered\\u000a palladium electrode shaped as a parallelepiped was used. After six days of electrolysis at 200 mA\\/cm2, a simultaneous emission of neutrons, tritium excess in the electrolytic solution and temperature rapid increase were observed.\\u000a During the event which lasted 4 minutes, we

D. Gozzi; P. L. Cignini; L. Petrucci; M. Tomellini; G. De Maria; S. Frullani; F. Garibaldi; F. Ghio; M. Jodice

1990-01-01

429

Solubility of palladium in silicate melts: Implications for core formation in the Earth  

Microsoft Academic Search

Palladium solubilities in silicate melts of anorthite-diopside-eutectic composition were determined at a wide range of oxygen fugacities, from pure O 2 to f o2 slightly below the iron-wüstite buffer and at temperatures ranging from 1343 to 1472°C. Experiments were performed by heating palladiumloops with silicates inside a gas controlled furnace. Palladium concentrations were determined by neutron activation analysis. Repeated analyses

A. Borisov; H. Palme; B. Spettel

1994-01-01

430

A One-Step Conversion of Benzene to Phenol with a Palladium Membrane  

Microsoft Academic Search

Existing phenol production processes tend to be energy-consuming and produce unwanted by-products. We report an efficient process using a shell-and-tube reactor, in which a gaseous mixture of benzene and oxygen is fed into a porous alumina tube coated with a palladium thin layer and hydrogen is fed into the shell. Hydrogen dissociated on the palladium layer surface permeates onto the

Shu-ichi Niwa; Muthusamy Eswaramoorthy; Jalajakumari Nair; Anuj Raj; Naotsugu Itoh; Hiroshi Shoji; Takemi Namba; Fujio Mizukami

2002-01-01

431

Asymmetric palladium-catalyzed allylic alkylation using dialkylzinc reagents: a remarkable ligand effect.  

PubMed

A serendipitously discovered palladium-catalyzed asymmetric allylic alkylation reaction with diorganozinc reagents, which displays broad functional group compatibility, is reported. This novel transformation hinges on a remarkable ligand effect which overrides the standard "umpolung" reactivity of allyl-palladium intermediates in the presence of dialkylzincs. Owing to its mild conditions, enantioselective allylic alkylations of racemic allylic electrophiles are possible in the presence of sensitive functional groups. PMID:24888236

Misale, Antonio; Niyomchon, Supaporn; Luparia, Marco; Maulide, Nuno

2014-07-01

432

Noble Metal Catalysts for Mercury Oxidation in Utility Flue Gas: Gold, Palladium and Platinum Formulations  

SciTech Connect

The use of noble metals as catalysts for mercury oxidation in flue gas remains an area of active study. To date, field studies have focused on gold and palladium catalysts installed at pilot scale. In this article, we introduce bench-scale experimental results for gold, palladium and platinum catalysts tested in realistic simulated flue gas. Our initial results reveal some intriguing characteristics of catalytic mercury oxidation and provide insight for future research into this potentially important process.

Presto, A.A.; Granite, E.J

2008-07-01

433

Nanoscale Pd\\/Fe bimetallic particles: Catalytic effects of palladium on hydrodechlorination  

Microsoft Academic Search

Reported herein is a study on the catalytic properties of palladium for hydrodechlorination using nanoscale zero-valent iron particles. Temperature-dependent experiments and X-ray diffraction (XRD) are conducted to characterize reactions of chlorinated ethylenes with nanoscale Fe and Pd\\/Fe particles. XRD results suggest bimetallic structures are created as a result of Pd(II) reduction by zero-valent iron and the degree of surface palladium

Hsing-Lung Lien; Wei-Xian Zhang

2007-01-01

434

Thermodynamics for complex formation between palladium(ii) and oxalate.  

PubMed

Complex formation between [Pd(H2O)4](2+) and oxalate (ox = C2O4(2-)) has been studied spectrophoto-metrically in aqueous solution at variable temperature, ionic strength and pH. Thermodynamic parameters at 298.2 K and 1.00 mol dm(-3) HClO4 ionic medium for the complex formation [Pd(H2O)4](2+) + H2ox ? [Pd(H2O)2(ox)] + 2H3O(+) with equilibrium constant K1,H (in mol dm(-3)) are log10K1,H = 3.38 ± 0.08, ?H = -33 ± 3 kJ mol(-1), and ?S = -48 ± 11 J K(-1) mol(-1), as determined from spectrophotometric equilibrium titrations at 15.0, 20.0, 25.0 and 31.0 °C. Thermodynamic overall stability constants ? (in (mol dm(-3))(-n), n = 1,2) for [Pd(H2O)2(ox)] and [Pd(ox)2](2-) at zero ionic strength and 298.2 K, defined as the equilibrium constants for the reaction Pd(2+) + nox(2-) ? [Pd(ox)n](2-2n) (water molecules omitted) are log10? = 9.04 ± 0.06 and log10? = 13.1 ± 0.3, respectively, calculated by use of Specific Ion Interaction Theory from spectrophotometric titrations with initial hydrogen ion concentrations of 1.00, 0.100 and 0.0100 mol dm(-3) and ionic strengths of 1.00, 2.00 or 3.00 mol dm(-3). The values derived together with literature data give estimated overall stability constants for Pd(ii) compounds such as [Pd(en)(ox)] and cis-[Pd(NH3)2Cl2], some of them analogs to Pt(ii) complexes used in cancer treatment. The palladium oxalato complexes are significantly more stable than palladium(ii) complexes with monodentate O-bonding ligands. A comparison between several different palladium complexes shows that different parameters contribute to the stability variations observed. These are discussed together with the so-called chelate effect. PMID:24912768

Pilný, Radomír; Lubal, P?emysl; Elding, Lars I

2014-07-22

435

Theoretical and experimental study of palladium(II) extraction from hydrochloric acid solutions into Aliquat 336\\/PVC membranes  

Microsoft Academic Search

The extraction of palladium(II) from its hydrochloric acid solutions into poly(vinyl chloride) (PVC)-based membranes containing Aliquat 336 chloride as both the extractant and the plasticizer was experimentally studied. The results showed that these membranes extracted palladium(II) rapidly and to a very high degree. This property can be used either for the analytical determination of trace levels of palladium(II) or for

Spas D. Kolev; Yukio Sakai; Robert W. Cattrall; Rohani Paimin; Ian D. Potter

2000-01-01

436

Determination of platinum and palladium in geological materials by neutron-activation analysis after fire-assay preconcentration  

USGS Publications Warehouse

Fire-asay preconcentration followed by neutron-activation analysis permits the determination of as little as 0.5 ppM of platinum and 0.5 ppM of palladium on a 20-g sample. Platinum and palladium are separated with carriers and beta-counted. Results for the platinum and palladium content of seven U.S.G.S. standard rocks are presented. ?? 1971.

Rowe, J. J.; Simon, F. O.

1971-01-01

437

The use of palladium to obtain reproducible boundary conditions for permeability measurements using galvanostatic charging  

NASA Astrophysics Data System (ADS)

The diffusion current of hydrogen through palladium in an electrochemical cell initially rises linearly with the charging current, reaches a steady “plateau” value, and then rises again. The diffusivity of hydrogen in palladium was measured using standard transient techniques in the initial region of low current density. Combining this value with the measured value of diffusion current at the plateau level gave a concentration of hydrogen at the entrance surface of the palladium that was the same for three different palladium thicknesses, and was equal to the saturation value in ? palladium. It is proposed that this can be used as a known and reproducible effective hydrogen pressure (0.019 atm) if palladium is plated onto other metals before measuring their permeability in an electrochemical cell. Experimental evidence for this was obtained from permeability measurements made on several thicknesses of iron. Permeation studies were also made on AISI 410 stainless steel and tin plated mild steel. The measured value for electrolytic tinplate was 107 times that expected from extrapolation of high temperature data. This could be attributed to grain boundaries or porosity covering 0.003 pct of the area. The permeability values of iron and stainless steel are 8.4 x 1012 and 2.8 x 1013 H atom/cm • s • ?atm, respectively.

Bowker, J.; Piercy, G. R.

1985-05-01

438

Ditching Investigation of a 1/18-Scale Model of the North American B-45 Airplane  

NASA Technical Reports Server (NTRS)

An investigation of a 1/18-scale dynamically similar model of the North American B-45 airplane was made to observe the ditching behavior and determine the proper landing technique to be used in an emergency water landing. Various conditions of damage were simulated to determine the behavior which probably would occur in a full-scale ditching. The behavior of the model was determined from high-speed motion-picture records, time-history acceleration records, and visual observations. It was concluded that the airplane should be ditched at the maximum nose-high attitude with the landing flaps full down for minimum landing speed. During the ditching, the nose-wheel and bomb-bay doors probably will be torn away and the rear of the fuselage flooded. A violent dive will very likely occur. Longitudinal decelerations of approximately 5g and vertical accelerations of approximately -6g (including gravity) will be experienced near the pilots' compartment. Ditching braces installed in the bomb bay will tend to improve the behavior slightly but will be torn away along with the bomb-bay doors. A hydroflap installed ahead of the nose-wheel doors will eliminate the dive and failure of the nose-wheel doors, and substantially reduce the motions and accelerations.

Fisher, Lloyd J.; Thompson, William C.

1949-01-01

439

Ditching Tests of a 1/18-Scale Model of the Lockheed Constellation Airplane  

NASA Technical Reports Server (NTRS)

Tests were made of a 1/18-scale dynamically similar model of the Lockheed Constellation airplane to investigate its ditching characteristics and proper ditching technique. Scale-strength bottoms were used to reproduce probable damage to the fuselage. The model was landed in calm water at the Langley tank no. 2 monorail. Various landing attitudes, speeds, and fuselage configuration were simulated. The behavior of the model was determined from visual observations, by recording the longitudinal decelerations, and by taking motion pictures of the ditchings. Data are presented in tabular form, sequence photographs, and time-history deceleration curves. It was concluded that the airplane should be ditched at a medium nose-high landing attitude with the landing flaps full down. The airplane will probably make a deep run with heavy spray and may even dive slightly. The fuselage will be damaged and leak substantially but in calm water probably will not flood rapidly. Maximum longitudinal decelerations in a calm-water ditching will be about 4g.

Fisher, Lloyd J.; Morris, Garland J.

1948-01-01

440

Accuracy of relativistic energy-consistent pseudopotentials for superheavy elements 111-118: Molecular calibration calculations  

SciTech Connect

Relativistic energy-consistent pseudopotentials modelling the Dirac-Coulomb-Breit Hamiltonian with a finite nucleus model for the superheavy elements with nuclear charges 111-118 were calibrated in atomic and molecular calculations against fully relativistic all-electron reference data. Various choices for the adjustment of the f-potentials were investigated and an improved parametrization is recommended. Using the resulting pseudopotentials relativistic all-electron reference data can be reproduced at the self-consistent field level with average absolute (relative) errors of 0.0030 A (0.15%) for bond lengths and 2.79 N m{sup -1} (1.26%) for force constants for 24 diatomic test molecules, i.e., neutral or singly charged monohydrides, monofluorides, and monochlorides with closed-shell electronic structure. At the second-order Moller-Plesset perturbation theory level the corresponding average deviations are 0.0033 A (0.15%) for bond lengths and 2.86 N m{sup -1} (1.40%) for force constants. Corresponding improved f-potentials were also derived for the pseudopotentials modelling in addition the leading contributions from quantum electrodynamics.

Hangele, Tim; Dolg, Michael [Institute for Theoretical Chemistry, University of Cologne, Greinstr. 4, 50939 Cologne (Germany)

2013-01-28

441

Reaction 13C(n,p)13B at 118 MeV  

NASA Astrophysics Data System (ADS)

Cross sections at six angles between 0° and 19° in the center-of-mass system have been measured for the ground-state transition in the reaction 13C(n,p)13B at En=118 MeV. The 0° cross section gives a value of 186+/-25 MeV fm3 for the volume integral of the spin-isospin component of the central part of the effective N-N interaction. The theoretical value is 161 MeV fm3 at 100 MeV. A distorted-wave impulse-approximation calculation for the angular distribution of the ground-state transition, (1/2-,1/2) to (3/2-,3/2), compares well with the measurement. The 0° measurement is compared with other (n,p) and (p,n) measurements on 6Li, 12C, and 13C to test the universal proportionality of these cross sections to the inverse ? decay. A falloff in the proportionality constant in going to low energy is confirmed.

Martoff, C. J.; Hanna, S. S.; Poc?ani?, D.; Wang, K.; Cummings, W. J.; Byrd, R. C.; Foster, C. C.

1996-11-01

442

Study of tin oxide: Surface properties and palladium adsorption  

NASA Astrophysics Data System (ADS)

Surface properties of various single-crystalline SnO2 surfaces were studied and the growth of palladium was investigated in the low-coverage regime. Metal - oxide structures play an important role in microelectronics and nanotechnology. They are also widely used in catalysis. Small catalytically-active metal particles on metal oxide substrates are key features in the gas sensing mechanism: they dramatically increase the sensitivity and selectivity of solid-state gas sensors towards target gases. Tin Oxide is widely used in solid-state gas sensors for detection of combustible and toxic gases. Its sensitivity and selectivity strongly depends on catalytic dopants, such as Pd or Pt, on the surface of the material. Thus, the characterization of Pd growth on tin oxide may give new insights into the catalytic and gas sensing mechanisms, and also help to understand fundamental steps that lead to various metal-on-oxide growth modes. Upon deposition of Pd onto the reduced (101) surface of a SnO2 single crystal, 1D cluster growth was observed. Starting from very low coverages, one-dimensional Pd clusters grow on the terraces, which indicates that the Pd wets the reduced tin oxide surface. Pd deposition on the oxidized surface results in randomly distributed three-dimensional Pd clusters. The clusters are distributed at step edges and on terraces without any apparent preferential adsorption sites. The one-dimensional clusters are imaged in scanning tunneling microscopy (STM) as straight, parallel nanostructures oriented along the [-101] direction, all with the same characteristic width of 0.5 nm and a height of 1 monolayer (ML). X-ray photoelectron spectroscopy (XPS) experiments show no sign of Pd oxidation; i.e. Pd grows as a metal. There is a 0.5 eV shift in the Pd 3d 5/2 core level peak position to lower binding energy that occurs during the initial stages of the growth on the reduced surface. This is an indication of charge transfer from the Pd clusters to the substrate. Coverage-dependent Ultraviolet Photoelectron Spectroscopy (UPS) spectra show that, at submonolayer Pd coverages, a Pd 4d-derived peak appears at the same position (3eV from Fermi edge) in the band gap as the Sn surface state and shifts towards the Fermi edge as coverage increases. Angular resolved photoemission data of the valence band of the clean reduced SnO2 surface and the Pd dosed reduced surface shows a strong correlation between the Sn 5s derived surface state and the Pd 4d state. The position, as well as the shape of Pd 4d peak closely follows the position and the shape of the 5s derived Sn peak in both low-index directions. This is a sign of a strong electronic interaction, hybridization between Pd 4d and Sn 5s derived states. Scanning tunneling microscopy experiments on a clean, reduced SnO 2 (100)-(1x1) surface reveal surface defects with zero, one, and two dimensions. Point defects consist of missing SnO/SnO2 units. Line defects are probably crystallographic shear planes that extend to the surface and manifest themselves as rows of atoms, shifted half a unit cell along the [010] direction. Their ends act as preferential nucleation sites for the formation of Pd clusters upon vapor-deposition. Submonolayer coverages of Pd deposited on the reduced surface at room temperature by vapour deposition result in the formation of three-dimensional clusters nucleating on the terraces. Areas of a more reduced surface phase, i.e. elongated "holes", observed at the surface after annealing to higher temperatures, still with a (1x1) structure and a half-unit-cell deep, form at [001]-oriented step edges. Recently, the use of nanobelts and nanoribbons has been suggested as novel materials for gas sensing applications. The large surface-to-volume ratio of the semiconducting metal oxide nanobelts and the congruence of the carrier screening length with their lateral dimensions make them highly sensitive and efficient transducers of surface chemical processes into electrical signal. The surface morphology of an individual nanobelts (NB) was studied with STM. Atom

Katsiev, Khabiboulakh

443

Development of cadmium/silver/palladium separation by ion chromatography with quadrupole inductively coupled plasma mass spectrometry detection for off-line cadmium isotopic measurements.  

PubMed

A separation method was investigated to perform off-line cadmium isotopic measurements on a (109)Ag transmutation target. Ion chromatography (IC) with Q ICPMS detection (quadrupole inductively coupled plasma mass spectrometry detection) was chosen to separate cadmium from the isobarically interfering elements, silver and palladium, present in the sample. The optimization of chromatographic conditions was particularly studied. Several anion and cation columns (Dionex AG11(®), CS10(®) and CS12(®)) were compared with different mobile phases (HNO(3), HCl). The separation procedure was achieved with a carboxylate-functionalized cation exchange CS12 column using 0.5 M HNO(3) as eluent. The developed technique yielded satisfactory results in terms of separation factors (greater than 5) and provides an efficient solution to obtain rapidly purified cadmium fractions (decontamination factors higher 100,000 for silver and palladium) which can directly be analyzed by multi collection inductively coupled plasma mass spectrometry (MC ICPMS). By applying the proposed procedure, accurate and precise cadmium isotope ratios were determined for the irradiated (109)Ag transmutation target. PMID:21703628

Gautier, C; Bourgeois, M; Isnard, H; Nonell, A; Stadelmann, G; Goutelard, F

2011-08-01

444

42 CFR 436.118 - Children for whom adoption assistance or foster care maintenance payments are made.  

Code of Federal Regulations, 2013 CFR

...2013-10-01 false Children for whom adoption assistance or foster care maintenance...Needy § 436.118 Children for whom adoption assistance or foster care maintenance...provide Medicaid to children for whom adoption assistance or foster care...

2013-10-01

445

25 CFR 39.118 - How does a student receive gifted and talented services in subsequent years?  

Code of Federal Regulations, 2011 CFR

...2011-04-01 false How does a student receive gifted and talented... Indians BUREAU OF INDIAN AFFAIRS, DEPARTMENT OF THE INTERIOR...Programs § 39.118 How does a student receive gifted and talented...subsequent years? For each student receiving gifted and...

2011-04-01

446

41 CFR 102-118.130 - Must my agency use a GBL for express, courier, or small package shipments?  

Code of Federal Regulations, 2013 CFR

... false Must my agency use a GBL for express, courier, or small package shipments...102-118.130 Must my agency use a GBL for express, courier, or small package shipments...using GSA's schedule for small package express delivery, the terms and conditions...

2013-07-01

447

36 CFR 223.118 - Appeal process for small business timber sale set-aside program share recomputation decisions.  

Code of Federal Regulations, 2010 CFR

...2010-07-01 2010-07-01 false Appeal process for small business timber sale set-aside program share recomputation...Contract Administration § 223.118 Appeal process for small business timber sale set-aside program share...

2010-07-01

448

36 CFR 223.118 - Appeal process for small business timber sale set-aside program share recomputation decisions.  

Code of Federal Regulations, 2010 CFR

...2009-07-01 2009-07-01 false Appeal process for small business timber sale set-aside program share recomputation...Contract Administration § 223.118 Appeal process for small business timber sale set-aside program share...

2009-07-01

449

Telomerization of amino acids with butadiene, catalyzed by palladium complexes  

SciTech Connect

The telomerization of ..cap alpha..-, ..beta..-, ..gamma..-, and epsilon-amino acids having various structures with butadiene under the influence of the three-component palladium catalyst Pd(acac)/sub 2/-PPh/sub 3/-AlEt/sub 3/ was investigated in DMSO-toluene solution. The ..cap alpha..- and epsilon-aliphatic and also the ..cap alpha..-, ..beta..-, and ..gamma..-aromatic amino acids react with butadiene, giving the products from octadienylation at the amino group exclusively. Under the conditions of telomerization aliphatic ..beta..-amino acids are cleaved with the formation of unsaturated tertiary amines. In the case of aliphatic ..gamma..-amino acids it is possible to obtain telomers alkylated at the carbonyl group.

Dzhemilev, U.M.; Fakhretdinov, R.N.; Telin, A.G.

1987-01-10

450

Palladium bridged gold nanocylinder dimer: plasmonic properties and hydrogen sensitivity.  

PubMed

Plasmonic nanodimers facilitate electromagnetic hotspots at their gap junction. By loading these gap junctions with nanomaterials, the plasmonic properties of nanodimer can be varied. In this study, we bridged the gap junction of gold (Au) nanocylinder dimer with palladium (Pd), and numerically evaluated the plasmonic properties of the designed nanostructure. We simulated the far-field extinction spectra of Pd bridged Au nanocylinder dimer, and identified the dipole and quadrupole plasmon modes at 839 and 578 nm, respectively. By varying the geometrical parameters of the Pd bridge, we revealed the ability to tune the dipolar plasmon resonance of the bridged dimer. Further, we exploited the hydrogen sensitivity of Pd bridge to harness the bridged-Au dimer as nanoplasmonic hydrogen sensor. Such nano-optical detection platforms have minimal spatial footprint and can be further harnessed for chip-based plasmonic sensing. PMID:22505158

Dasgupta, Arindam; Kumar, G V Pavan

2012-04-10

451

COMPARATIVE CORROSION BEHAVIOR OF TWO PALLADIUM CONTAINING TITANIUM ALLOYS  

SciTech Connect

The ASTM standard B 265 provides the requirements for the chemical composition of titanium (Ti) alloys. It is planned to use corrosion resistant and high strength titanium alloys to fabricate the drip shield at the proposed Yucca Mountain Repository. Titanium grade (Gr) 7 (R52400) and other Ti alloys are currently being characterized for this application. Ti Gr 7 contains 0.15% Palladium (Pd) to increase its corrosion performance. In this article we report results on the comparative short term corrosion behavior of Ti Gr 7 and a Ruthenium (Ru) containing alloy (Ti Gr 33). Ti Gr 33 also contains a small amount of Pd. Limited electrochemical testing such as polarization resistance and cyclic potentiodynamic curves showed that both alloys have a similar corrosion behavior in the tested environments.

T. Lian, T. Yashiki, T. Nakayama, T. Nakanishi, R. B. Rebak

2006-07-23

452

Palladium-doped Nanoporous Carbon Fibers for Hydrogen Storage  

SciTech Connect

Pd-free and Pd-containing activated carbon fibers (Pd-ACF) were synthesized from isotropic pitch as a carbon precursor. The source of Pd was a palladium salt that was premixed with pitch before carbonization. Hydrogen adsorption was measured at near-ambient temperatures (5 to 80 oC) and moderate pressures (up to 20 bar). It was found that adsorption on Pd-ACF is always higher than that on corresponding ACF, and in excess of what it would be expected based solely on formation of Pd hydride. This fact can be explained based on the mechanism of hydrogen spillover. It was also found that temperature and pressure have opposite effects on physisorption and spillover. It was hypothesized that a narrow temperature range exists, where the kinetic advantage of H2 spillover in Pd-ACF overlaps synergistically with the thermodynamic advantage of physisorption, thus contributing to enhanced uptakes compared with the Pd-free carbons.

Gallego, Nidia C [ORNL; Contescu, Cristian I [ORNL; Bhat, Vinay V [ORNL; van Benthem, Klaus [ORNL; Tekinalp, Halil [Clemson University; Edie, Dan [Clemson University

2008-01-01

453

Neutral Pion-Catalyzed Fusion in Palladium Lattice  

SciTech Connect

From symmetric meson theory, the formation of helium nucleus from two deuterons, i.e., fusion, requires necessarily a direct force due to exchange of two neutral pions, which do not actually compose the deuteron nucleus. The neutral pions are provided by two photons, which are produced by emission of excited collective electrons derived from the palladium atoms. The introduction of the pions makes it possible to reduce remarkably an internuclear distance, enhancing the fusion rate for helium formation. The dynamic interaction is interpreted as the result of condensation of deuterons into octahedral interstitial sites by electrolysis and contraction of the deuteron octahedra around the Pd{sup 10-{delta}} atom with the help of the electron-phonon charge-density wave coupling.

Fukuhara, Mukio

2003-01-15

454

Creep in a palladium-enriched high-copper amalgam.  

PubMed

Palladium additions to a dispersed phase high-copper amalgam have been shown recently to suppress markedly the eta' (Cu6Sn5) concentration and decrease creep. A detailed study of the dental and 24 h creep for Pd containing high-copper amalgams and six commercial controls as a function of applied temperature and stress was performed. One part of Ag-Cu or Ag-Cu-Pd dispersants with substitutions of up to 20wt/o Pd for either Ag or Cu was blended with two parts of traditional amalgam alloy. Various temperatures from 25 to 60 degrees C and stresses from 36 to 72 MPa were applied to the samples during the test. For commercial controls and experimental amalgams with no Pd, creep is a strong function of temperature and stress. The experimental amalgam containing up to 10wt/o Pd, Pd substituted for Ag, demonstrated essentially constant creep over the temperature and stress range applied. PMID:3408790

Greener, E H; Chung, K H; Lin, J H

1988-05-01

455

Chemical activity of palladium clusters: Sorption of hydrogen.  

PubMed

Samples of Pd/SiO2 with average cluster size of palladium (d(Pd)) ranging from 1 to 10 nm were prepared by different methods, such as incipient wetness impregnation (IW), ion exchange (IE), and sol-gel (SG). The dispersion (D(Pd)) for prepared Pd/SiO2 samples varied with the method of preparation and showed a trend of IW < IE < SG. Chemical interaction between the dispersed nanopalladium and hydrogen gas was calorimetrically studied as a function of hydrogen uptake. Measured profiles of interaction energy vary with the d(Pd) of studied samples. The initial heat of hydrogen chemisorption (Q(Hi)) also steeply increases for particles with d(Pd) smaller than 2 nm. PMID:17064140

Huang, Sheng-Yang; Huang, Chin-Da; Chang, Boh-Tze; Yeh, Chuin-Tih

2006-11-01

456

Palladium film decoupler for amperometric detection in electrophoresis chips.  

PubMed

Demonstrated in this article is that a palladium metal film can be applied to decouple the electric circuitry of electrochemical detection from that of the electrophoretic separation in an electrophoresis chip. The Pd solid-state field decoupler, as well as the working electrodes, is thermally evaporated onto the plastic chip and oriented vertically across the separation channel. After the sample zones flow over the Pd decoupler, their electrochemical response is measured at working electrodes in the downstream pathway. Because the electrodes are on the separation channel, the electrode channel alignment is no longer a problem. For a separation channel of roughly 200 microm in width and 75 microm in depth in 10 mM phosphate (pH 5.1), the noise level at the working electrode is < 15 pA at an electric field of 570 V/cm. PMID:11248889

Chen, D; Hsu, F L; Zhan, D Z; Chen, C

2001-02-15

457

Synthesis, structure and dynamics of NHC-based palladium macrocycles.  

PubMed

A series of macrocyclic CNC pincer pro-ligands based on bis(imidazolium)lutidine salts with octa-, deca- and dodecamethylene spacers have been prepared and their coordination chemistry investigated. Using a Ag2O based transmetallation strategy, cationic palladium(II) chloride complexes [PdCl{CNC-(CH2)n}][BAr(F)4] (n = 8, 10, 12; Ar(F) = 3,5-C6H3(CF3)2) were prepared and fully characterised in solution, by NMR spectroscopy and ESI-MS, and in the solid-state, by X-ray crystallography. The smaller macrocyclic complexes (n = 8 and 10) exhibit dynamic behaviour in solution, involving ring flipping of the alkyl spacer across the Pd-Cl bond, which was interrogated by variable temperature NMR spectroscopy. In the solid-state, distorted coordination geometries are observed with the spacer skewed to one side of the Pd-Cl bond. In contrast, a static C2 symmetric structure is observed for the dodecamethylene based macrocycle. For comparison, palladium(II) fluoride analogues [PdF{CNC-(CH2)n}][BAr(F)4] (n = 8, 10, 12) were also prepared and their solution and solid-state structures contrasted with those of the chlorides. Notably, these complexes exhibit very low frequency (19)F chemical shifts (ca. -400 ppm) and the presence of C-H···F interactions ((2h)J(FC) coupling observed by (13)C NMR spectroscopy). The dynamic behaviour of the fluoride complexes is largely consistent with the smaller ancillary ligand; [PdF{CNC-(CH2)8}][BAr(F)4] exceptionally shows C(2v) time averaged symmetry in solution at room temperature (CD2Cl2, 500 MHz) as a consequence of dual fluxional processes of the pincer backbone and alkyl spacer. PMID:24201818

Andrew, Rhiann E; Chaplin, Adrian B

2014-01-21

458

Dechlorination of chlorophenols using magnesium-palladium bimetallic system.  

PubMed

Ninety-four percent removal of 10 mg L(-1) of pentachlorophenol (PCP) was achieved by treatment with 154.5mM Mg(0) and 0.063 mM K(2)PdCl(6) in the presence of 175 mM acetic acid in 1h reaction time. Dechlorination of PCP was found to be sequential and phenol was identified as the end product along with accumulation of trace concentrations of tetra- and trichlorophenols. Scanning electron microscopy (SEM) and energy dispersive X-ray spectroscopy (EDX) revealed that palladium in its metallic form (Pd(0)) produced by reduction of Pd4+, was spatially separated from magnesium granules when acid was included in the reaction. These colloidal palladium particles generated active reductive species of hydrogen and dechlorinated chlorophenols. In the absence of acid, the efficiency of dechlorination of PCP by Pd/Mg(0) system was very low and chief mechanism of removal of the compound was through sorption onto solid surfaces. Thus, it was important to include acid in the system to: (a) facilitate corrosion of Mg(0) and reduction of Pd4+ to Pd(0), (b) provision of protons to produce H2, (c) retard formation of insoluble oxides and hydroxides that may deposit on the magnesium granules and sorb PCP and its partially dechlorinated products and. Application of 154.5 mM Mg(0)/0.063 mM K(2)PdCl(6) on PCP, 2,4,5-trichlorophenol (TCP) and 2-chlorophenol (MCP) with organic chloride equivalence showed that the rate and extent of removal increased with decrease in number of chlorine atoms on phenol. PMID:17300867

Patel, Upendra D; Suresh, Sumathi

2007-08-17

459

Selective hydrogenation of phenylacetylene on pumice-supported palladium catalysts  

SciTech Connect

The liquid phase, selective hydrogenation of phenylacetylene on pumice-supported palladium catalysts has been studied for a large range of metallic dispersions (14% {le} D{sub x} {le} 62%). The kinetics were analyzed by a five-parameter mathematical model. The mechanism was determined by the contribution of three basic routes involving only surface species in the rate-determining steps. The hydrogenation of phenylacetylene to styrene is {open_quotes}structure insensitive{close_quotes}. The disappearance rate constant of styrene produced from phenylacetylene is slightly lower than that of phenylacetylene and does not change in the case of the direct hydrogenation of styrene on the same Pd/pumice catalyst. However, Q{sub 3} (the ratio of adsorption constants K{sub Eb}/K{sub St}, where Eb is ethylbenzene and St is styrene), which is typical of a zero-order reaction (Q{sub 3}{r_arrow}0) in the case of the direct hydrogenation, is practically constant (Q{sub 3}{approx_equal}2) in the case of dehydrogenation of styrene produced from phenylacetylene. This is explained by the formation, in the latter case, of polymeric species or other species which are difficult to hydrogenate and by the consequent occupation of active sites so that the adsorption of styrene is inhibited. These species are also thought to be responsible for a flattening effect in the catalytic activity. Activity and selectivity data are critically analyzed and compared with those reported for other supported palladium catalysts. Since Pd/pumice catalysts also show high activity and selectivity at high metal dispersions, they could be of interest for industrial applications. 48 refs., 9 figs., 3 tabs.

Duca, D; Liotta, L.F.; Deganello, G. [Universita di Palermo (Italy)] [Universita di Palermo (Italy)

1995-06-01

460

Effects of starting material of aluminum doped zinc oxide underlayer on the electric properties of palladium doped silver film  

NASA Astrophysics Data System (ADS)

Crystallographic and electric properties of a palladium doped silver (Ag-Pd) layer formed on an aluminum doped zinc oxide (AZO) film in the multilayer system of Ag-Pd(10.5 nm)/AZO(42 nm)/glass were investigated. All of the films in this study were deposited by dc magnetron sputtering. Two kinds of sputtering targets, aluminum doped zinc metal (AZ) and AZO, were used for the deposition of AZO films. The AZ target was sputtered in an oxygen or carbon dioxide atmosphere whereas the AZO target was sputtered in an argon or argon/oxygen atmosphere. The Ag-Pd layers were deposited under the fixed sputtering condition. From x-ray diffraction patterns it was found that the most developed Ag(111) peak appeared in the case of the Ag-Pd film on the AZO layer deposited from the AZ metal target with oxygen. Atomic force microscope observation revealed that the smallest surface roughness was obtained in this case. Electrical resistivity of the Ag-Pd layer changed by up to 17% depending on deposition conditions and the target materials of the underlayer. The Ag-Pd film deposited on the AZO layer from the AZ target in an oxygen atmosphere also showed the lowest resistivity of 7.1×10-6 ? cm. The smallest refractive index of Ag-Pd film was shown by the same sample from an analysis using spectroscopic ellipsometry (SE). Deposition of a thin metal (Zn-Al) overlayer on Ag-Pd/AZO/glass increased the overall resistivity of the multilayer. This may imply the diffusion of zinc atoms into the Ag-Pd layer, however, the resistivity recovery was observed after some storage time, which suggests the effect of an electron scattering at the surface.

Oyama, T.; Maekawa, M.; Yanagisawa, T.

2003-07-01

461

Fam118B, a newly identified component of Cajal bodies, is required for Cajal body formation, snRNP biogenesis and cell viability.  

PubMed

Cajal bodies are specialized and dynamic compartments in the nucleus that are involved in the biogenesis of small nuclear ribonucleoproteins (snRNPs). Because of the dynamic and varied roles of Cajal bodies, it is of great interest to identify the components of Cajal bodies to better understand their functions. We performed a genome-wide screen to identify proteins that colocalize with coilin, the marker protein of Cajal bodies. In this study, we identified and characterized Fam118B as a newly discovered component of Cajal bodies. Fam118B is widely expressed in a variety of cell lines derived from various origins. Overexpression of Fam118B changes the canonical morphology of Cajal bodies, whereas depletion of Fam118B disrupts the localization of components of Cajal bodies, including coilin, the survival of motor neuron protein (SMN) and the Sm protein D1 (SmD1, also known as SNRPD1). Moreover, depletion of Fam118B reduces splicing capacity and inhibits cell proliferation. In addition, Fam118B associates with coilin and SMN proteins. Fam118B depletion reduces symmetric dimethylarginine modification of SmD1, which in turn diminishes the binding of SMN to this Sm protein. Taken together, these data indicate that Fam118B, by regulating SmD1 symmetric dimethylarginine modification, plays an important role in Cajal body formation, snRNP biogenesis and cell viability. PMID:24569877

Li, Yujing; Fong, Ka-Wing; Tang, Mengfan; Han, Xin; Gong, Zihua; Ma, Wenbin; Hebert, Michael; Songyang, Zhou; Chen, Junjie

2014-05-01

462

Cavity Ring Down measurements on carbon dioxide at high pressure at 1.18 ?m  

NASA Astrophysics Data System (ADS)

The interpretation of emission/absorption spectra from the Venus' atmosphere, consisting of 97% of carbon dioxide, presents a challenge to the scientific community. Indeed, due to the high values of pressure and CO2 volume mixing ratio, the contributions of complex phenomena such as Collision-Induced-Absorption (CIA), line mixing and far wings absorption, must be accurately taken into account. In particular, the so called atmospheric windows, one of which is at 1.18 ?m, allow to observe from an orbiting spacecraft the planet Venus down to its surface, where the pressure reaches 92 bars and the temperature 450°C. The accurate knowledge of the atmospheric optical properties in the windows is then very important to reduce the uncertainty of the retrieved parameters. In order to study this set of very weak absorption lines and to distinguish each single contribution, it's necessary to work at high densities with very long optical path. We've realized a Cavity Ring Down (CRD) system which consists of a DFB laser used to illuminate a stable optical cavity. The cavity, consisting of an inner quartz tube formed by two highly reflecting plano-concave mirrors (99.98%), is placed inside a steel hermetic tube capable to sustain a pressure up to 50 bar. The CRD can reach an equivalent optical path of 5 Km. This innovative design allows to use the cavity under stringent pressure conditions without affecting its performance otherwise compromised by the mechanical stress. Using the DFB laser, whose full scan range is from 1179 to 1182 nm, we measured the carbon dioxide absorption coefficients varying the pressure from 1 up to 38 bar and maintaining the temperature constant at 294K. The data are fitted as a function of density and we can distinguish a linear loss rate due to the Rayleigh scattering and a quadratic term likely due to CIA bands and far wings (continuum absorption). The latter contribution is in very good agreement with the absorption coefficient used in B. Bézard et al. Icarus vol.216, Issue 1, November 2011, pp 173-183.

Stefani, S.; Snels, M.; Piccioni, G.; Adriani, A.

2012-12-01

463

The effect of mass transfer on the catalytic combustion of benzene and methane over palladium catalysts supported on porous materials  

Microsoft Academic Search

Catalytic combustion of benzene and methane over palladium catalysts supported on FAU and MOR zeolites and MCM-41 and KIT-1 mesoporous materials were studied to illustrate the effect of pore size and shape of supports on their catalytic activities. The palladium catalysts supported on mesoporous materials showed high activity and a steep increase in the conversion of benzene with rising temperature.

Min-Woong Ryoo; Sang-Gwi Chung; Jong-Ho Kim; Yo Soon Song; Gon Seo

2003-01-01

464

A thermogravimetric study of the effect of palladium catalyst residue on the degradation of ethylene–carbon monoxide alternating copolymer  

Microsoft Academic Search

The thermal degradation of ethylene–carbon monoxide alternating copolymer was studied as a function of the palladium catalyst residue concentration under inert atmosphere and in the presence of oxygen. The copolymer thermal behavior was analyzed by thermogravimetry and accelerated aging monitored through UV-Visible and EPR spectroscopies. The traces of palladium do not influence the temperature at which the copolymer starts to

Silvia DeVito; Simona Bronco

1999-01-01

465

Closure Report for Corrective Action Unit 118: Area 27 Super Kukla Facility, Nevada Test Site, Nevada with ROTC 1, Revision 0  

SciTech Connect

This CR provides documentation and justification for the closure of CAU 118 without further corrective action. This justification is based on process knowledge and the results of the investigative and closure activities conducted in accordance with the CAU 118 SAFER Plan: Streamlined Approach for Environmental Restoration (SAFER) Plan for CAU 118: Area 27 Super Kukla Facility, Nevada Test Site, Nevada (NNSA/NSO, 2006). The SAFER Plan provides information relating to site history as well as the scope and planning of the investigation. This CR also provides the analytical and radiological survey data to confirm that the remediation goals were met as specified in the CAU 118 SAFER Plan (NNSA/NSO, 2006). The Nevada Division of Environmental Protection (NDEP) approved the CAU 118 SAFER Plan (Murphy, 2006), which recommends closure in place with use restrictions (URs).

Mark Burmeister

2007-09-01

466

Palladium salts of heteropolyacids as catalysts in the Wacker oxidation of 1-butene  

SciTech Connect

Palladium salts of heteropolyacids (PdHPAs) of the Keggin series H{sub 3+n}PV{sub n}Mo{sub 12-n}O{sub 40} supported on silica, have been used successfully as catalysts in the gas-phase Wacker oxidation of 1-butene. In such catalysts the palladium reaction centre and the redox component are combined in one complex. At 343 K and atmospheric pressure a high initial butanone yield of more than 0.2 g g{sup -1}{sub cat}h{sup -1}, in combination with a very high butanone selectivity of more than 98%, can be obtained. In the steady state, the activity of the catalyst is more than a factor of 10 lower than the initial activity, due to slow reoxidation of reduced palladium-heteropolyanion complexes. The rate of reoxidation depends on the composition of the HPA, the palladium loading, and the reaction conditions. The reaction order of 0.5 in the O{sub 2} partial pressure indicates the dissociation of dioxygen to be rate determining. The degree of hydration of the HPA appears to be important for the activity and stability of the catalysts. Spent catalysts can be regenerated by an oxidation treatment in air at temperatures around 525 K. Regeneration becomes more difficult with high palladium loading of the catalyst. 8 refs., 8 figs.

Stobbe-Kreemers, A.W.; van der Lans, G.; Makkee, M. [Delft Univ. of Technology (Netherlands)] [and others] [Delft Univ. of Technology (Netherlands); and others

1995-07-01

467

A new pathway for hydroamination. Mechanism of palladium-catalyzed addition of anilines to vinylarenes.  

PubMed

The mechanism of the hydroamination of vinylarenes with anilines catalyzed by phosphine-ligated palladium triflates was uncovered. eta3-Arylethyl diphosphine palladium triflate complexes, which result from migratory insertion of vinylarene into a palladium hydride triflate, were shown to be the resting state of the catalytic cycle. A series of these complexes has been isolated and fully characterized. The [(R)-Tol-BINAP][1-(2-naphthyl)ethyl]palladium triflate derivative 1a was crystallographically characterized. This complex reacted with aniline to form the N-phenethylaniline product in 83% yield. Reaction of the benzylic derivative [(R)-Tol-BINAP](eta3-benzyl)palladium triflate with aniline also formed the N-benzylaniline product in a high 87% yield. Predominant inversion of configuration from the reaction between 1a, which is enantiopure, and aniline showed that external attack of the amine on the eta3-arylethyl ligand occurred to form the product. This product from reaction of aniline with 1a is the opposite enantiomer to that obtained from the catalytic process. Thus, a minor diastereomer gives the major enantiomer in the catalytic cycle, and the major diastereomer gives the minor enantiomer. Consistent with this assertion, kinetic studies showed that the major diastereomer formed product with a rate constant roughly 3.5 times slower than the rate constant for the catalytic process that contains all diastereomers. PMID:11841274

Nettekoven, Ulrike; Hartwig, John F

2002-02-20

468

Synthesis and characterization of chitosan and grape polyphenols stabilized palladium nanoparticles and their antibacterial activity.  

PubMed

Based on enhanced effectiveness, the new age drugs are nanoparticles of polymers, metals or ceramics, which can combat conditions like cancer and fight human pathogens like bacteria. In this present study we aimed for a green approach to synthesize palladium nanoparticles by reducing palladium chloride salts with nontoxic and biodegradable polymeric chitosan and grape polyphenols and confirmed by FTIR, TEM, SEM and UV-spectroscopy. We also extended our study to show the efficacy of the grape and chitosan impregnated palladium nanoparticles as an antibacterial agent against Escherichia coli. Antibacterial assays were carried out with a representative gram-negative bacterium, E. coli and a gram-positive bacterium, Staphylococcus aureus. Commendable efforts have been made to explore this property using electron microscopy, which has revealed size dependent interaction of palladium nanoparticles conjugates with bacteria by disrupting cell membranes and the leakage of cytoplasm. Therefore, the observed results imply that grape and chitosan-based nano palladium conjugates prepared in our present system are promising candidates for a wide range of biomedical and general applications. PMID:22225943

Amarnath, Kanchana; Kumar, Jayanthi; Reddy, Tejesh; Mahesh, Vakka; Ayyappan, Senniyanallur Rathakrishnan; Nellore, Jayshree

2012-04-01

469

Heterologous Expression of BetL, a Betaine Uptake System, Enhances the Stress Tolerance of Lactobacillus salivarius UCC118  

Microsoft Academic Search

Given the increasing commercial and clinical relevance of probiotic cultures, improving the technological robustness of what are often process-sensitive cultures is an important biological goal. The nisin-controlled expression system was used to direct the heterologous expression of the listerial betaine uptake system BetL in the probiotic strain Lactobacillus salivarius UCC118. Following nisin induction, strains expressing betL exhibited a significant increase

Vivien M. Sheehan; Roy D. Sleator; Gerald F. Fitzgerald; Colin Hill

2006-01-01

470

NKG2D? IFN-?? CD8? T cells are responsible for palladium allergy.  

PubMed

Nickel, cobalt, and chromium are well known to be causal agents of allergic contact dermatitis. Palladium (Pd) can also cause allergic disease and exposure results from wide use of this metal in dental restorations and jewelry. Metal allergy is categorized as a delayed-type hypersensitivity, and metal-responsive T cell clones have been isolated from allergic patients. However, compared to nickel, little is known about the pathology of allergic disease mediated by Pd, and pathogenic T cells are poorly understood. To identify the pathogenic T cells that are responsible for onset of Pd allergy, we enriched metal-responsive lymphocytes by sequential adoptive transfer of involved lymph node cells. Here we show that sequential adoptive transfer gradually increased the incidence and the intensity of Pd allergy, and CD8? T cells are responsible for the disease as CD8? T cell-depleted mice and ?2-microglobulin-deficient mice did not develop Pd allergy. In addition, we found that draining lymph node cells skewed toward CD8? T cells in response to Pd challenge in 8th adoptive transferred recipient mice. The CD8? T cells expressed NKG2D, a costimulatory molecule involved in the production of IFN-?. NKG2D ligand was also induced in Pd-injected tissues. Furthermore, both NKG2D ligand-transgenic mice, where NKG2D is downmodulated, and IFN-?-deficient mice showed impaired Pd allergy. Taken together, these results indicate that IFN-?-producing NKG2D? CD8? T cells are responsible for Pd allergy and suggest that NKG2D is a potential therapeutic target for treatment of metal allergy. PMID:24533050

Kawano, Mitsuko; Nakayama, Masafumi; Aoshima, Yusuke; Nakamura, Kyohei; Ono, Mizuho; Nishiya, Tadashi; Nakamura, Syou; Takeda, Yuri; Dobashi, Akira; Takahashi, Akiko; Endo, Misato; Ito, Akiyo; Ueda, Kyosuke; Sato, Naoki; Higuchi, Shigehito; Kondo, Takeru; Hashimoto, Suguru; Watanabe, Masamichi; Watanabe, Makoto; Takahashi, Tetsu; Sasaki, Keiichi; Nakamura, Masanori; Sasazuki, Takehiko; Narushima, Takayuki; Suzuki, Ryuji; Ogasawara, Kouetsu

2014-01-01

471

Hydrogen Permeability of Palladium Membrane for Steam-Reforming of Bio-Ethanol Using the Membrane Reactor  

NASA Astrophysics Data System (ADS)

A Palladium membrane was prepared by electro-less plating method on porous stainless steel. The catalytic hydrogen production by steam-reforming of biomass-derived ethanol (bio-ethanol) using a Pd membrane was analyzed by comparing it with those for the reaction using reagent ethanol (the reference sample). And the hydrogen permeability of the palladium membrane was investigated using the same palladium membrane (H2/He selectivity = 249, at ?P = 0.10 MPa, 873 K). As a result, for bio-ethanol, deposited carbon had a negative influence on the hydrogen-permeability of the palladium membrane and hydrogen purity. The sulfur content in the bio-ethanol may have promoted carbon deposition. By using a palladium membrane, it was confirmed that H2 yield (%) was increased. It can be attributed that methane was converted from ethanol and produced more hydrogen by steam reforming, due to the in situ removal of hydrogen from the reaction location.

Kinouchi, Kouji; Katoh, Masahiro; Horikawa, Toshihide; Yoshikawa, Takushi; Wada, Mamoru

472

Metal-support interactions during the adsorption of CO on thin layers and islands of epitaxial palladium  

NASA Technical Reports Server (NTRS)

Islands and continuous layers of palladium were grown in an ultrahigh vacuum on substrates of Mo(110)c(14 x 7)-O, designated MoO(x), and of clean Mo(110). It was found that as-deposited islands and layers exhibited bulk palladium adsorption properties for CO when deposited at room temperature and for palladium thicknesses in excess of about 3 monolayers. CO adsorption was drastically reduced, however, on annealing. For islands, annealing temperatures of as low as 400 K led to some reduction in CO adsorption whereas more severe reductions were found to occur at 600 K for islands and at 800 K for continuous multilayers. The deactivation depended on the palladium thickness, the substrate species and the extent of thermal treatments. Auger electron spectroscopy, temperature-programmed desorption and Delta-Phi measurements were combined to interpret the deactivation behavior in terms of substrate-support interactions involving the diffusion of substrate species towards the palladium surface.

Park, C.; Poppa, H.; Soria, F.

1984-01-01

473

Vapor space characterization of waste tank 241-TX-118: Results from samples collected on 12/16/94  

SciTech Connect

This report describes inorganic and organic analyses results from samples obtained from the headspace of the Hanford waste storage Tank 241-TX-118 (referred to as Tank TX-118). The results described here were obtained to support safety and toxicological evaluations. A summary of the results for inorganic and organic analytes is listed in Table 1. Detailed descriptions of the results appear in the text. Quantitative results were obtained for the inorganic compounds ammonia (NH{sub 3}), nitrogen dioxide (NO{sub 2}), nitric oxide (NO), and water (H{sub 2}O). Sampling for hydrogen cyanide (HCN) and sulfur oxides (SO{sub x}) was not requested. In addition, quantitative results were obtained for the 39 TO-14 compounds plus an additional 14 analytes. Of these, 3 were observed above the 5-ppbv reporting cutoff. Twenty three organic tentatively identified compounds (TICs) were observed above the reporting cutoff of (ca.) 10 ppbv, and are reported with concentrations that are semiquantitative estimates based on internal-standard response factors. The 10 organic analytes with the highest estimated concentrations are listed in Table 1 and account for approximately 84% of the total organic components in Tank TX-118. Two permanent gases, carbon dioxide (CO{sub 2}) and nitrous oxide (N{sub 2}O), were also detected.

Lucke, R.B.; Ligotke, M.W.; McVeety, B.D. [and others

1995-10-01

474

Shaping surface of palladium nanospheres through the control of reaction parameters  

NASA Astrophysics Data System (ADS)

Solid, cracked, and flower-shaped surfaces of palladium nanospheres with high yields and good uniformity were successfully prepared by a wet chemical method. On the basis of the experimental data, the same size of palladium nanosphere with different surface morphologies can be regulated only by changing the amount of ammonium hydroxide and reductant in one experimental system. The as-prepared products were studied by transmission electron microscopy (TEM), scanning electron microscopy (SEM) and x-ray diffraction (XRD). In addition, surface-enhanced Raman scattering (SERS) spectra on the as-prepared different surface of palladium nanospheres exhibit high activity towards p-aminothiophenol (PATP) detection, and the result further reveals that the predominance of the a1 vibration mode in the SERS spectra via an electromagnetic (EM) mechanism is significant.

Wang, Lianmeng; Wang, Lihua; Tan, Enzhong; Guo, Lin; Han, Xiaodong

2011-07-01

475

Effect of recasting on the oxidation layer of a palladium-silver porcelain alloy  

SciTech Connect

The oxidation zone of a commercial palladium-silver porcelain alloy was compared after repeated casting with and without the addition of new alloy. The intensity of palladium, silver, tin, indium, and O K-alpha near the oxidation zone was analyzed with XMA. The intensity curves of tin, silver, and oxygen increased progressively through each generation despite the addition of new alloy. The thickness of the oxidation zone and the microporosities at the internal oxidation zone increased through each generation without the addition of new alloy. Although the findings indicated that the oxidation zone was favorably formed by adding new alloy, 50% by weight, for four generations, the silver and metallic oxides of the oxidation zone increased through each generation. The reuse of the palladium-silver porcelain alloy remains questionable.

Hong, J.M.; Razzoog, M.E.; Lang, B.R.

1988-04-01

476

The effect of recasting on the oxidation layer of a palladium-silver porcelain alloy.  

PubMed

The oxidation zone of a commercial palladium-silver porcelain alloy was compared after repeated casting with and without the addition of new alloy. The intensity of palladium, silver, tin, indium, and O K-alpha near the oxidation zone was analyzed with XMA. The intensity curves of tin, silver, and oxygen increased progressively through each generation despite the addition of new alloy. The thickness of the oxidation zone and the microporosities at the internal oxidation zone increased through each generation without the addition of new alloy. Although the findings indicated that the oxidation zone was favorably formed by adding new alloy, 50% by weight, for four generations, the silver and metallic oxides of the oxidation zone increased through each generation. The reuse of the palladium-silver porcelain alloy remains questionable. PMID:3283327

Hong, J M; Razzoog, M E; Lang, B R

1988-04-01

477

Hydrogen gas sensing with networks of ultra-small palladium nanowires formed on filtration membranes.  

SciTech Connect

Hydrogen sensors based on single Pd nanowires show promising results in speed, sensitivity, and ultralow power consumption. The utilization of single Pd nanowires, however, face challenges in nanofabrication, manipulation, and achieving ultrasmall transverse dimensions. We report on hydrogen sensors that take advantage of single palladium nanowires in high speed and sensitivity and that can be fabricated conveniently. The sensors are based on networks of ultrasmall (<10 nm) palladium nanowires deposited onto commercially available filtration membranes. We investigated the sensitivities and response times of these sensors as a function of the thickness of the nanowires and also compared them with a continuous reference film. The superior performance of the ultrasmall Pd nanowire network based sensors demonstrates the novelty of our fabrication approach, which can be directly applied to palladium alloy and other hydrogen sensing materials.

Zeng, X. Q.; Latimer, M. L.; Xiao, Z. L.; Panuganti, S.; Welp, U.; Kwok, W. K.; Xu, T. (Materials Science Division); (Northern Illinois Univ.)

2010-11-29

478

Novel macroporous palladium cation crosslinked chitosan membranes for heterogeneous catalysis application.  

PubMed

A novel palladium supported on chitosan porous membrane heterogeneous catalyst has been prepared by freeze-drying of Pd(2+)-crosslinked chitosan gel solution. The prepared membrane catalyst has three-dimensional porous structure (porosity: >70%). The crosslinking effects of Pd(2+) to chitosan were good for the improvement of the mechanical properties and thermal stabilities. Pd(2+) cations have been shown not only as the crosslinker, but also as the catalytic active sites. The reductive palladium species of the recycled membrane catalysts was found in the nanometer scale (20-40nm). Excellent cross-coupling yields were achieved using as low as 0.12mol% palladium catalyst loading for the Heck-type reaction of aromatic halides with acrylates. The catalyst could be recycled six times without obvious decreased conversion. PMID:24768971

Zeng, Minfeng; Yuan, Xia; Yang, Zhen; Qi, Chenze

2014-07-01

479

Synthesis of monodispersed palladium nanoparticles using tannic acid and its optical non-linearity  

NASA Astrophysics Data System (ADS)

Palladium nanoparticles with average size 11.3 nm have been synthesized via a one-step reduction and capping method. This colloidal route using tannic acid does not require any other surfactant or capping agent to direct the growth of palladium nanoparticles. The effect of temperature on the conversion of Pd2+ ion to Pd0 is investigated. The growth process of nanoparticles is monitored using UV-visible spectra. The morphology and phase transformation have been confirmed by transmission electron microscopy and X-ray diffraction. An attempt to reveal the capping mechanism of tannic acid is done through FTIR analysis. The optical non-linearity of the samples was studied using open aperture Z-scan technique. The significance of this protocol for the generation of environmentally benign palladium nanoparticles lies mainly in its simplicity and cost effectiveness.

Meena Kumari, M.; Aromal, S. Aswathy; Philip, Daizy

2013-02-01

480

Well-defined N-heterocyclic carbenes-palladium(II) precatalysts for cross-coupling reactions.  

PubMed

Metal-catalyzed cross-coupling reactions, notably those permitting C-C bond formation, have witnessed a meteoritic development and are now routinely employed as a powerful synthetic tool both in academia and in industry. In this context, palladium is arguably the most studied transition metal, and tertiary phosphines occupy a preponderant place as ancillary ligands. Seriously challenging this situation, the use of N-heterocyclic carbenes (NHCs) as alternative ligands in palladium-catalyzed cross-coupling reactions is rapidly gaining in popularity. These two-electron donor ligands combine strong sigma-donating properties with a shielding steric pattern that allows for both stabilization of the metal center and enhancement of its catalytic activity. As a result, the number of well-defined NHC-containing palladium(II) complexes is growing, and their use in coupling reactions is witnessing increasing interest. In this Account, we highlight the advantages of this family of palladium complexes and review their synthesis and applications in cross-coupling chemistry. They generally exhibit high stability, allowing for indefinite storage and easy handling. The use of well-defined complexes permits a strict control of the Pd/ligand ratio (optimally 1/1), avoiding the use of excess costly ligand that usually requires end-game removal. Furthermore, it partly removes the "black box" character often associated with cross-coupling chemistry and catalyst formation. In the present Account, four main classes of NHC-containing palladium(II) complexes will be presented: palladium dimers with bridging halogens, palladacycles, palladium acetates and acetylacetonates, and finally pi-allyl complexes. These additional ligands are best described as a protecting shell that will be discarded going from the palladium(II) precatalyst to the palladium(0) true catalyst. The synthesis of all these precatalysts generally requires simple and short synthetic procedures. Their catalytic activity in different cross-coupling reactions is discussed and put into context. Remarkably, some NHC-containing catalytic systems can achieve extremely challenging coupling reactions such as the formation of tetra-ortho-biphenyl compounds and perform reactions at very low loadings of palladium (ppm levels). The chemistry described here, combining fundamental organometallic, catalysis, and pure organic methodology, remains rich in opportunities considering that only a handful of palladium(II) architectures have been studied. Hence, en route to an "ideal catalyst", [(NHC)Pd(II)] compounds exhibit remarkable stability and allow for fine-tuning of the NHC and of surrounding ligands in order to control the activation and the catalytic activity. Finally, unlike [Pd(PPh(3))(4)], [(NHC)Pd(II)] compounds have so far been examined only in palladium-mediated reactions (most often cross-coupling such as the Suzuki-Miyaura and Heck reactions), leaving a treasure trove of exciting discoveries to come. PMID:18774825

Marion, Nicolas; Nolan, Steven P

2008-11-18

481

A UNIFORM ANALYSIS OF 118 STARS WITH HIGH-CONTRAST IMAGING: LONG-PERIOD EXTRASOLAR GIANT PLANETS ARE RARE AROUND SUN-LIKE STARS  

SciTech Connect

We expand on the results of Nielsen et al., using the null result for giant extrasolar planets around the 118 target stars from the Very Large Telescope (VLT) NACO H- and Ks-band planet search (conducted by Masciadri and collaborators in 2003 and 2004), the VLT and MMT Simultaneous Differential Imager survey, and the Gemini Deep Planet Survey to set constraints on the population of giant extrasolar planets. Our analysis is extended to include the planet luminosity models of Fortney et al., as well as the correlation between stellar mass and frequency of giant planets found by Johnson et al. Doubling the sample size of FGKM stars strengthens our conclusions: a model for extrasolar giant planets with power laws for mass and semimajor axis as given by Cumming et al. cannot, with 95% confidence, have planets beyond 65 AU, compared to the value of 94 AU reported by Nielsen et al., using the models of Baraffe et al. When the Johnson et al. correction for stellar mass (which gives fewer Jupiter-mass companions to M stars with respect to solar-type stars) is applied, however, this limit moves out to 82 AU. For the relatively new Fortney et al. models, which predict fainter planets across most of parameter space, these upper limits, with and without a correction for stellar mass, are 182 and 234 AU, respectively.

Nielsen, Eric L.; Close, Laird M., E-mail: enielsen@as.arizona.ed [Steward Observatory, University of Arizona, Tucson, AZ 85721 (United States)

2010-07-10

482

Ferrofluid-based dispersive solid phase extraction of palladium.  

PubMed

A new mode of dispersive solid phase extraction based on ferrofluid has been developed. In this method, an appropriate amount of ferrofluid is injected rapidly into the aqueous sample by a syringe. Since the sorbent is highly dispersed in the aqueous phase, extraction can be achieved within a few seconds. The ferrofluid can be attracted by a magnet and no centrifugation step is needed for phase separation. Palladium was used as a model compound in the development and evaluation of the extraction procedure in combination with flame atomic absorption spectrometry. The experimental parameters (pH, DDTC concentration, type and concentration of eluent, the amount of adsorbent, extraction time, and the effect of interfering ions) were investigated in detail. Under the optimized conditions, the calibration graph was linear over the range of 1-100 ?g L(-1) and relative standard deviation of 3.3% at 0.1 ?g mL(-1) was obtained (n=7). The limit of detection and enrichment factor (EF) was obtained to be 0.35 ?g L(-1) and 267, respectively. The maximum adsorption capacity of the adsorbent at optimum conditions was found to be 24.6 mg g(-1) for Pd(II). The method was validated using certified reference material, and has been applied for the determination of trace Pd(II) in actual samples with satisfactory results. PMID:23618148

Farahani, Malihe Davudabadi; Shemirani, Farzaneh; Gharehbaghi, Maysam

2013-05-15

483

Supercritical Fluid Attachment of Palladium Nanoparticles on Aligned Carbon Nanotubes  

SciTech Connect

Nanocomposite materials consisting of Pd nanoparticles deposited on aligned multi-walled carbon nanotubes have been fabricated through hydrogen reduction of palladium precursor in supercritical carbon dioxide. The supercritical fluid processing allowed deposition of high-density Pd nanoparticles (~5-10 nm) on both as-grown (unfunctionalized) and functionalized (using HNO3 oxidation) nanotubes. However, the wet processing for functionalization results in pre-agglomerated, bundle-shaped nanotubes thus significantly reducing the effective surface area for Pd particle deposition, although the bundling provides more secure, lock-in-place positioning of nanotubes and Pd catalyst particles. The nanotube bundling is substantially mitigated by Pd nanoparticle deposition on the unfunctionalized and geometrically separated nanotubes, which provides much higher catalyst surface area. Such nanocomposite materials utilizing geometrically secured and aligned nanotubes can be useful for providing much enhanced catalytic activities to chemical and electrochemical reactions (e.g. fuel cell reactions), and eliminate the need for tedious catalyst recovery process after the reaction is completed.

Ye, Xiangrong; Lin, Yuehe; Wai, Chien M.; Talbot, J.; Jin, Sungho

2005-06-01

484

Catalytic hydrolysis of ammonia borane via cobalt palladium nanoparticles.  

PubMed

Monodisperse 8 nm CoPd nanoparticles (NPs) with controlled compositions were synthesized by the reduction of cobalt acetylacetonate and palladium bromide in the presence of oleylamine and trioctylphosphine. These NPs were active catalysts for hydrogen generation from the hydrolysis of ammonia borane (AB), and their activities were composition dependent. Among the 8 nm CoPd catalysts tested for the hydrolysis of AB, the Co(35)Pd(65) NPs exhibited the highest catalytic activity and durability. Their hydrolysis completion time and activation energy were 5.5 min and 27.5 kJ mol(-1), respectively, which were comparable to the best Pt-based catalyst reported. The catalytic performance of the CoPd/C could be further enhanced by a preannealing treatment at 300 °C under air for 15 h with the hydrolysis completion time reduced to 3.5 min. This high catalytic performance of Co(35)Pd(65) NP catalyst makes it an exciting alternative in pursuit of practical implementation of AB as a hydrogen storage material for fuel cell applications. PMID:21766875

Sun, Daohua; Mazumder, Vismadeb; Metin, Önder; Sun, Shouheng

2011-08-23

485

Superconductivity at 23 K in yttrium palladium boride carbide  

NASA Astrophysics Data System (ADS)

Copper oxide compounds have dominated superconductivity research since 1986 because of their very high transition temperatures (T(sub c)s). In contrast, no new families of high-T(sub c) intermetallic compounds have been discovered since the A15-type Nb3X compounds were first reported in 1953. The intermetallics with highest T(sub c)s have all been based on niobium, with the highest T(sub c)s being 20.7 K for bulk Nb(3)Ga and 23.2 K for sputtered films of Nb(3)Ge. Here we report the observation of superconductivity at 23 K in a multiple-phase bulk sample of a quaternary intermetallic, yttrium palladium boride carbide. This is higher than any T(sub c) reported previously for a bulk intermetallic compound. Although the materials are not yet single-phase, the superconducting volume fraction is large. We propose that this compound may represent the first of a new family of superconducting intermetallics with relatively high T(sub c)s.

Cava, R. J.; Takagi, H.; Batlogg, B.; Zandbergen, H. W.; Krajewski, J. J.; Peck, W. F., Jr.; van Dover, R. B.; Felder, R. J.; Siegrist, T.; Mizuhashi, K.

1994-01-01

486

High sensitivity of palladium on porous silicon MSM photodetector  

NASA Astrophysics Data System (ADS)

In this work, the nanocrystalline porous silicon (PS) is prepared through the simple electrochemical etching of n-type Si (1 0 0) under the illumination of a 100 W incandescent white light. SEM, AFM, Raman and PL have been used to characterize the morphological and optical properties of the PS. SEM shows uniformed circular pores with estimated sizes, which range between 100 and 500 nm. AFM shows an increase in its surface roughness (about 6 times compared to c-Si). Raman spectra of the PS show a stronger peak with FWHM=4.3 cm -1 and slight blueshift of 0.5 cm -1 compared to Si. The room temperature photoluminescence (PL) peak corresponding to red emission is observed at 639.5 nm, which is due to the nano-scaled size of silicon through the quantum confinement effect. The size of the Si nanostructures is estimated to be around 7.8 nm from a quantized state effective mass theory. Thermally untreated palladium (Pd) finger contact was deposited on the PS to form MSM photodetector. Pd/PS MSM photodetector shows lower dark (two orders of magnitude) and higher photocurrent compared to a conventional Si device. Interestingly, Pd/PS MSM photodetector exhibits 158 times higher gain compared to the conventional Si device at 2.5 V.

Abd Rahim, A. F.; Hashim, M. R.; Ali, N. K.

2011-02-01

487

Seasonal variation of palladium, elemental carbon and aerosol mass concentrations in airborne particulate matter  

NASA Astrophysics Data System (ADS)

Palladium, elemental carbon (EC) and mass concentrations in the aerosol fraction below 10 ?m aerodynamic diameter (PM10) were investigated in a 1 year time series in Klagenfurt and Salzburg, two urban sites in Austria. For PM10 mass and EC concentrations no remarkable differences were observed between the two sites whereas for palladium distinctly different concentration levels were determined. The monthly averaged palladium concentration in Salzburg varied between 7.1 and 31.2 pg m -3. In Klagenfurt the palladium concentration ranged from 2.9 to 5.0 pg m -3. The higher traffic density and the different driving conditions in Salzburg were assessed to be responsible for the enhanced palladium concentrations. At both sampling sites the seasonal variation of PM10 and EC was similar showing decreased concentrations in the warm period of the year and increased concentrations in the cold season. Generally the seasonal pattern of an individual aerosol constituent depends on meteorological variations and changes in the source emission and transformation rates of the investigated species. With the use of palladium as an atmospheric dilution tracer it was possible to eliminate seasonal meteorological variations and to determine changes in source emission or atmospheric transformation rates of PM10 mass and elemental carbon concentrations. Approximately 20% of the enhanced PM10 mass and EC concentrations in the cold season could be attributed to reduced atmospheric dilution. The remaining variation (+22-50%) reflects changes in other processes such as source emission or atmospheric transformation rates of the examined aerosol constituents.

Limbeck, Andreas; Rendl, Josef; Heimburger, G.; Kranabetter, A.; Puxbaum, Hans

488

Mechanistic studies of palladium thin film growth from palladium(II) β-diketonates. 2. Kinetic analysis of the transmetalation reaction of bis(hexafluoroacetylacetonato)palladium(II) on copper surfaces  

Microsoft Academic Search

The reaction pathways and kinetics for the selective deposition of palladium on copper from the metal-organic precursor Pd(hfac)â have been established by means of reactive molecular beam-surface scattering where a flux of Pd(hfac)â (ranging from 10¹³ to 10¹⁴ molecules cm⁻² s⁻¹) impinges continuously on the copper surface. The surface selectivity of the deposition process is a consequence of a `redox

Wenbin Lin; Ralph G. Nuzzo; Gregory S. Girolami

1996-01-01

489

Targets Directory.  

National Technical Information Service (NTIS)

This directory is intended to serve as a quick-look reference of target information. Section 1 describes target command and control systems, while section 2 discusses specific aerial, land, seaborne, and tow targets. Appendixes contain government points o...

1988-01-01

490

Palladium(II) and platinum(II) bind strongly to an engineered blue copper protein  

PubMed Central

Studies of palladium(II) and platinum(II) binding to well-characterized proteins contribute to understanding the influence of these metals in the environment and the body. The well-characterized apo-protein of azurin has a soft-metal binding site that may be exposed to solvent by mutation of a coordinating histidine-117 residue to glycine. Palladium(II) and platinum(II) form strong 1:1 adducts with the apo form of H117G azurin. A combination of UV-visible, CD, and ICP-MS techniques suggests that the metal binds specifically at His-46 and Cys-112 of the protein.

McLaughlin, Matthew P.; Darrah, Thomas H.; Holland, Patrick L.

2011-01-01

491

Aqueous synthesis of copper nanocubes and bimetallic copper/palladium core-shell nanostructures.  

PubMed

We have synthesized copper nanocubes with uniform shape and size and copper/palladium core-shell bimetallic nanostructures in high yield by a two-stage procedure in the presence of dodecyl benzene sulfonic acid sodium. The copper nanocubes with a slight hole in the centers of the six {100} surfaces was prepared at the first stage. Later, the bimetallic copper/palladium core-shell nanostructures formed on the basis of the successive reduction of H2PdCl4 and the Pd growth on the surfaces of the Cu seeds. PMID:16768527

Zhou, Guangjun; Lu, Mengkai; Yang, Zhongsen

2006-06-20

492

Preparation of palladium nanoparticles–titanium electrodes as a new anode for direct methanol fuel cells  

Microsoft Academic Search

Pd nanoparticle\\/Ti electrodes are prepared by electroless plating of palladium on titanium plates. The morphology and surface\\u000a analysis of Pd nanoparticle\\/T