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The evaluators present in this publication spectroscopic data and level schemes from radioactive decay and nuclear reactions studies for all isobars with mass number A = 66. The first level- scheme of {sup 66}As, from (HI,xn{gamma}), has been included in this evaluation.
Techniques were studied to reinforce or strengthen electroformed nickel to allow a fuller utilization of electroforming as a reliable and low cost fabrication technique for regenerately cooled thrust chambers. Techniques for wire wrapping while electrodepositing were developed that can result in a structurally strong wall with less weight than a conventional electroformed wall. Also a technique of codepositing submicron sized THO2 particles with the nickel to form a dispersion strengthened structure was evaluated. The standard nickel cylinders exhibited an average hoop strength of 80,000 psi with a yield strength of 65,000 psi and a modulus of 25.6 x 10 to the 6th power psi. The as produced dispersion strengthened nickel showed a hoop strength of 97,000 psi with a yield strength of 67,000 psi. This is an increase of 17,000 psi or 21% over the standard nickel hoop strength. The wire wrapping cylinders showed an increased strength over the standard nickel test samples of 26,000 to 66,800 psi which is in the range of 26 to 104% increase in strength over the base standard nickel. These latter test results are indicative of a volume percent wire reinforcement from 15 to 31. The measured hoop strengths agree with calculated composite strengths based upon rule of mixtures.
Molybdenum sulfide-based catalysts, such as nickel–molybdenum on alumina (NiMoS x /Al 2 O 3 ), are widely used in hydrotreating and have potential for catalyzing waste plastic conversion via hydrogenolysis, yet their performance, such as reaction kinetics and network, for amide-rich polymer feeds is poorly defined. Here we combine Nylon 66 with the amide model compound, N,N-dibutylhexanediamide (DBDAD), to quantify hydrodeoxygenation (HDO) and hydrodenitrogenation (HDN) chemistry in a stirred batch reactor (53 bar H 2 , 280–320°C). DBDAD conversion is near-linear with time, indicating strong adsorption of the substrates on the active sites. Time-resolved product identification indicates parallel C─O first-cleavagedeoxygenation (DO) and C─N first-cleavagedenitrogenation (DN) sequences proceeding through amine and diol intermediates, respectively, to C 4 ─C 6 alkanes. Increasing temperature shifts selectivity toward DN, decreasing the initial r(DO)/r(DN) from 1.38 (280°C) to 0.69 (320°C), with an apparent activation energy of 173 kJ mol −1 for DBDAD conversion. At 300°C, nylon 66 converts faster than DBDAD, producing a complex mixture of oxygen- and nitrogen-containing species and an initial rate ratio r(DO)/r(DN) of 1.6. No heteroaromatic nitrogen products are detected by the method used. These results provide reaction pathways and product signatures relevant to hydro-processing catalysts exposed to polyamide-derived streams.
Here, corrosion testing of Hastelloy N in molten fluoride salt was performed in purified molten 2 7 LiF-BeF 2 (66-34mol%) (FLiBe) salt at 700°C for 1000 hours, in pure nickel and graphite capsules. In the nickel capsule tests, the near-surface region of the alloy exhibited an about 200 nm porous structure, an approximately 3.5 μm chromium depleted region, and MoSi 2 precipitates. In tests performed in graphite capsules, the alloy samples gained weight due to the formation of a variety of Cr 3 C 2 , Cr 7 C 3 , Mo 2 C and Cr 23 C 6 , carbide phases on the surface and in the subsurface regions of the alloy. A Cr depleted region was observed in the near-surface region where Mo thermally diffused toward either surface or grain boundary, which induced approximately 1.4 μm Ni 3 Fe alloy layer in this region. The carbide containing layer extended to about 7 μm underneath the Ni 3 Fe layer. The presence of graphite dramatically changes the mechanisms of corrosion attack in Hastelloy N in molten FLiBe salt. Evaluated by in terms of the depth of attack, graphite clearly accelerates corrosion, but the results appear to indicate that the formation of Cr 23 C 6 phase might stabilize the Cr and mitigate its dissolution in molten FLiBe salt.
A Monte Carlo simulation process was used to develop the U.S. daily range requirements for an electric vehicle from probability distributions of trip lengths and frequencies and average annual mileage data. The analysis shows that a car in the U.S. with a practical daily range of 82 miles (132 km) can meet the needs of the owner on 95% of the days of the year, or at all times other than his long vacation trips. Increasing the range of the vehicle beyond this point will not make it more useful to the owner because it will still not provide intercity transportation. A daily range of 82 miles can be provided by an intermediate battery technology level characterized by an energy density of 30 to 50 watt-hours per pound (66 to 110 W-hr/kg). Candidate batteries in this class are nickel-zinc, nickel-iron, and iron-air. The implication of these results for the research goals of far-term battery systems suggests a shift in emphasis toward lower cost and greater life and away from high energy density.
The effect of prolonged exposure to 750 C air on the tribological performance and dimensional stability of PM212, a high temperature, self-lubricating composite, is studied. PM212, by weight, contains 70 percent metal-bonded Cr3C2, 15 percent BaF2/CaF2 eutectic, and 15 percent silver. Rub blocks were fabricated from PM212 by cold isostatic pressing followed by sintering. Prior to tribo-testing, the rub blocks were exposed to 750 C air for periods ranging from 100 to 1000 hours. Then, the rub blocks were slid against nickel-based superalloy disks in a double-rub-block tribometer in air under a 66 N load at temperatures from 25 to 750 C with a sliding velocity of 0.36 m/s. Unexposed rub blocks were tested for baseline comparison. Friction coefficients ranged from 0.24 to 0.37 for the unexposed rub blocks and from 0.32 to 0.56 for the exposed ones. Wear for both the composite blocks and superalloy disks was typically in the moderate to low range of 10(exp -5) to 10(exp -6) mm(exp 3)/N-m. Friction and wear data were similar for the rub blocks exposed for 100, 500, and 1000 hours. Prolonged exposure to 750 C air increased friction and wear of the PM212 rub blocks at room temperature, but their triboperformance remained unaffected at higher temperatures, probably due to the formation of lubricious metal oxides. Dimensional stability of the composite was studied by exposing specimens of varying thicknesses for 500 hours in air at 750 C. Block thicknesses were found to increase with increased exposure time until steady state was reached after 100 hours of exposure, probably due to oxidation.
Homotopic sites in a well-controlled environment are not only ideal systems for mechanistic studies, but also allow optimal control of catalytic transformations. Sites having only a single metal cation and sites consisting of metal oxo complexes with few nickel (Ni) cations supported on the nodes of UiO-66 metal-organic framework (Ni-UiO-66) are studied for 1-butene dimerization. Monomeric Ni sites, which bind to the Zr 6 node via two Zr-OH(µ3) linkages, are active and selective for the dimerization of 1-butene to linear and mono-branched C 8 isomers. Ni oxo complexes with few Ni cations show lower activity and promote the oligomerization of transiently formed C 8 isomers. In conclusion, Kohn-Sham density function theory calculations combined with spectroscopic measurements and kinetic analyses indicate that dimerization follows a Cossee-Arlman reaction mechanism.
The evolution of single-particle neutron spectra in the N = 40 isotones {sup 60}Ca, {sup 62}Ti, {sup 64}Cr, {sup 66}Fe, {sup 68}Ni, and {sup 70}Zn is calculated on the basis of the mean-field model featuring a dispersive optical potential. The results of these calculations agree with the idea that the degree of collectivity becomes higher in the {sup 64}Сr nucleus and that the coupling of single-particle motion to this collectivity becomes stronger, as well as with available experimental data, which are indicative of the closure of the N = 40 subshell in {sup 68}Ni and of the trend toward this closure in {sup 60}Ca.
Probing shell structure at a large neutron excess has been of particular interest in recent times. Neutron-rich nuclei between the proton shell closures Z = 20 and Z = 28 offer an exotic testing ground for shell evolution. The development of the N = 40gap between neutron fp and lg{sub 9/2} shells gives rise to highly interesting variations of collectivity for nuclei in this region. While {sup 68}Ni shows doubly magic properties in level energies and transition strengths, this was not observed in neighbouring nuclei. Especially neutron-rich Fe isotopes proved particularly resistant to calculational approaches using the canonical valence space (fpg) resulting in important deviations of the predicted collectivity. Only an inclusion of the d{sub 5/2}-orbital could solve the problem [1]. Hitherto no transition strengths for {sup 66}Fe have been reported. We determined B(E2,2{sup +}{sub 1}{yields}0{sup +}{sub 1}) values from lifetimes measured with the recoil distance Doppler-shift method using the Cologne plunger for radioactive beams at National Superconducting Cyclotron Laboratory at Michigan State University. Excited states were populated by projectile Coulomb excitation for {sup 62,64,66}Fe. The data show a rise in collectivity for Fe isotopes towards N = 40. Results [2] are interpreted by means of a modified version of the Valence Proton Symmetry [3] and compared to shell model calculations using a new effective interaction recently developed for the fpgd valence space [4].
Reaction of [Ru{sub 2}(O{sub 2}CMe){sub 4}]Cl and K{sub 2}[Ni(CN){sub 4}] forms [Ru{sub 2}(O{sub 2}CMe){sub 4}]{sub 2}[Ni(CN){sub 4}] with the targeted layered structure possessing Ru-N{triple_bond}C-Ni linkages, albeit strained, with Ru-N{triple_bond}C and Ni-C{triple_bond}N angles in the range of 147-167{sup o}. The magnetic properties of [Ru{sub 2}(O{sub 2}CMe){sub 4}]{sub 2}[Ni(CN){sub 4}] can be fit to a zero-field splitting model with D/k{sub B} = 95 K (66 cm{sup -1}).
Three new coordination polymers, namely, {[Ni(H_2L)(bix)(H_2O)_2]·2h_2O}{sub n} (1), {[Ni(HL)(Hdpa)(H_2O)_2]·H_2O}{sub n} (2), {[Ni(L)_0_._5(bpp)(H_2O)]·H_2O}{sub n} (3) (H{sub 4}L=terphenyl-2,2′,4,4′-tetracarboxylic acid; bix=1,4-bis(imidazol-1-ylmethyl)benzene; dpa =4,4′-dipyridylamine; bpp=1,3-bis(4-pyridyl)propane), based on rigid H{sub 4}L ligand and different N-donor co-ligands, have been synthesized under hydrothermal conditions. Compound 1 features a 3D 4-connected 6{sup 6}-dia-type framework with H{sub 4}L ligand adopts a μ{sub 2}-bridging mode with two symmetry-related carboxylate groups in μ{sub 1}-η{sup 1}:η{sup 0} monodentate mode. Compound 2 displays a 1D [Ni(HL)(Hdpa)]{sub n} ribbon chains motif, in which the H{sub 4}L ligand adopts a μ{sub 2}-bridging mode with two carboxylate groups in μ{sub 1}-η{sup 1}:η{sup 1} and μ{sub 1}-η{sup 1}:η{sup 0} monodentate modes, while 3 possesses a (4,4)-connected 3D frameworks with bbf topology, with H{sub 4}L ligand displays a μ{sub 4}-bridging coordination mode. The H{sub 4}L ligand displays not only different deprotonated forms but also diverse coordination modes and conformations. The structural diversities among 1–3 have been carefully discussed, and the roles of N-donor co-ligands in the self-assembly of coordination polymers have been well documented. - Graphical abstract: Three nickel coordination polymers with different architectures based on mixed ligand system were synthesized and structurally characterized. Topology analyses indicate that 1 shows the 4-connected 6{sup 6}-dia net, 1D ribbon chains for 2 and 3D (4,4)-connected bbf network for 3. Display Omitted - Highlights: • Three Ni-based coordination polymers with distinct features have been prepared. • Compound 1 features a 3D 4-connected 66-dia-type framework, 2 displays a 1D [Ni(HL)(Hdpa)]{sub n} ribbon chains motif, while 3 possesses a (4,4)-connected 3D frameworks with bbf topology. • The “mixed ligand assembled” strategy is significant potential for network design.
This dataset describes the nickel-platinum (NiPt) solid solution binary alloy, where the two constituent elements nickel (Ni) and platinum (Pt) are randomly placed on the face centered cubic (FCC) crystal structure, with the lattice constant of 3.840 angstroms. The dataset comprises data for crystal structures with 108 atoms with 1,900 configurations. The data set was generated for concentrations ranging from 0at% of Pt to 100at% of Pt in the NiPt binary system, with increasing the concentration of Pt in the system every 5at%. For each one of the chemical compositions, 100 random configurations were generated, each with a different random seed. Each of the output files contains the mass, type, atomic coordinates, energy per atom, and forces in x, y, and z directions respectively. For each atomic configuration, the output was collected every 150 steps during the minimization stage and every 1000 steps during the replica exchange stage. Large-scale Atomic/Molecular Massively Parallel Simulator (LAMMPS) [1], which is a molecular dynamics code, was used to generate data for NiPt alloy. The simulation used the interatomic potential for NiPt binary system 'MEAM_LAMMPS_KimSeolJi_2017_PtNi__MO_020840179467_001' [3] from the OpenKIM library (Open Knowledgebase of Interatomic Models) [2]. This potential was developed based on the second nearest-neighbor modified embedded-atom method (2NN MEAM). The simulation process begins with the generation of the random NiPt structure and follows with the short minimization and replica exchange simulation. The minimization procedure adjusts atomic coordinates and performs energy minimization, which typically leads to a local potential energy minimum. The method used for the minimization was the conjugate gradient algorithm. A short replica exchange (parallel tempering) simulation involves four replicas (ensembles) of a system and follows the minimization stage. Multiple snapshots of the configuration were collected during the minimization and replica exchange stages. NiPt alloy is interesting due to its magnetic and charge transfer properties [4]. The data is provided in a compressed zipped folders atoms108.zip. The zipped folder contains the data structured in the following way: - Ni_ground_state.cfg --> atomic configuration for the pure nickel - Pt_ground_state.cfg --> atomic configuration for the pure platinum - Pt#_filtered --> folders containing atomic configurations for #at% concentration of platinum. The folder contains 100 atomic configurations, each saved in a subfolder - Each subfolder named config* is associated with a specific atomic configuration. Each of these subfolders contains files with .cfg format, corresponding to outputs for each atomic configuration The total number of atomic configurations contained in atoms108.zip is 66,132. This dataset is an extension to the dataset ORNL_AISD_NiPt [5] that has been previously released with crystal structures of 256 atoms, 864 atoms, and 2,048 atoms, with the same methodology for data collection. References [1] https://www.lammps.org/ [2] https://openkim.org/ [3] https://openkim.org/id/MEAM_LAMMPS_KimSeolJi_2017_PtNi__MO_020840179467_001 [4] El-Gendy, Ahmed A. and Hampel, Silke and Büchner, Bernd and Klingeler, Rüdiger, Tuneable magnetic properties of carbon-shielded NiPt-nanoalloys, RSC Adv., volume 6, issue 57, pages 52427-52433, 2016, The Royal Society of Chemistry, doi:10.1039/C6RA05910D [5] M. Karabin, M. Lupo Pasini, and M. Eisenbach. ORNL_AISD_NiPt. United States: N. p., 2023. Web. doi:10.13139/OLCF/1958172.
This study is a part of an experimental program to measure nuclear moments in transfer reactions. It aims to probe for a first time the nuclear -spin orientation in multi-nucleon transfer. Fist experiments were performed to measure the quadrupole moment of an isomeric state in {sup 66}Cu (I{sup p}i 6{sup -}, E{sub x} = 1154 keV, T{sub 1/2} = 595(20) ns) in single nucleon transfer and the population of mus isomers in {sup 66}Cu and {sup 63}Ni in multi-nucleon transfer. The experimentally tested methodology allows broad applications toward more exotic species and feasibility of these reactions to produce species away from stability.
A button solid oxide fuel cell with a La0.6Sr0.4Co0.2Fe0.8O3 cathode and a nickel-YSZ anode was tested over a range of temperatures from 650 to 800°C and a range of pressures from 101 to 724 kPa. The fuel was simulated steam-reformed kerosene and the oxidant was air. The observed increases in open circuit voltages (OCV) were accurately predicted by the Nernst equation. Kinetics also increased, although the power boost due to kinetics was about two thirds as large as the boost due to OCV. The total power boost in going from 101 to 724 kPa at 750°C and 0.8 volts was 66%. Impedance spectroscopy demonstrated a significant decrease in electrodic losses at elevated pressures. Complex impedance spectra were dominated by a combination of low frequency processes that decreased markedly with increasing pressure. A composite of high-frequency processes also decreased with pressure, but to a lesser extent. An empirical algorithm that accurately predicts the increased fuel cell performance at elevated pressures was developed for our results and was also suitable for some, but not all, data reported in the literature.
Thick films of YBa2Cu3O(7-x) have been deposited on highly polished alumina, magnesia spinel, nickel aluminum titanate (Ni-Al-Ti), and barium tetratitanate (Ba-Ti) substrates by the screen printing technique. Properties of the films were found to be highly sensitive to the choice of the substrate material. The film on Ba-Ti turned green after firing, due to a reaction with the substrate and were insulating. A film on Ni-Al-Ti had a Tc (onset) of about 95 K and lost 90 percent of its resistance by about 75 K. However, even at 4 K it was not fully superconducting, possibly due to a reaction between the film and the substrate and interdiffusion of the reaction products. The film on alumina had Tc (onset) of about 96 K, Tc (zero) of about 66 K, and Delta Tc of about 10 K. The best film was obtained on spinel and had Tc (onset) of about 94 K, zero resistance at 81 K, and a transition width of about 7 K.
Purpose: This study was designed to assess the clinical outcomes of patients treated by vertebral augmentation with nitinol endoprosthesis (VNE) to treat painful vertebral compression fractures. Methods: Forty patients with one or more painful osteoporotic VCF, confirmed by MRI and accompanied by back-pain unresponsive to a minimum 2 months of conservative medical treatment, underwent VNE at 42 levels. Preoperative and postoperative pain measured with Visual Analog Scale (VAS), disability measured by Oswestry Disability Index (ODI), and vertebral height restoration (measured with 2-dimensional reconstruction CT) were compared at last follow-up (average follow-up 15 months). Cement extravasation, subsequent fractures, and implant migration were recorded. Results: Long-term follow-up was obtained in 38 of 40 patients. Both VAS and ODI significantly improved from a median of 8.0 (range 5–10) and 66 % (range 44–88 %) to 0.5 (range 0–8) and 6 % (range 6–66 %), respectively, at 1 year (p < 0.0001). Vertebral height measurements comparing time points increased in a statistically significant manner (ANOVA, p < 0.001). Overall cement extravasation rate was 9.5 %. Discal and venous leakage rates were 7.1 and 0 % respectively. No symptomatic extravasations occurred. Five of 38 (13.1 %) patients experienced new spontaneous, osteoporotic fractures. No device change or migration was observed. Conclusions: VNE is a safe and effective procedure that is able to provide long-lasting pain relief and durable vertebral height gain with a low rate of new fractures and cement leakages.
Highlights: • 66 elements, including “critical strategic elements” were determined in UK EfW APC residues. • Metal pollutants (Zn, Pb, As, Cd, Cu, Mo, Sb, Sn, Se, Ag and In) are enriched in APC residues. • Metal pollutants were widely associated with fine deposits of highly soluble CaCl{sub x}OH{sub 2−x}. • Specific metal (Zn, Pb, Cu)-bearing minerals were also detected in APC residues. - Abstract: Air pollution control (APC) residues from energy-from-waste (EfW) are alkaline (corrosive) and contain high concentrations of metals, such as zinc and lead, and soluble salts, such as chlorides and sulphates. The EPA 3050B-extractable concentrations of 66 elements, including critical elements of strategic importance for advanced electronics and energy technologies, were determined in eight APC residues from six UK EfW facilities. The concentrations of Ag (6–15 mg/kg) and In (1–13 mg/kg), as well as potential pollutants, especially Zn (0.26–0.73 wt.%), Pb (0.05–0.2 wt.%), As, Cd, Cu, Mo, Sb, Sn and Se were found to be enriched in all APC residues compared to average crustal abundances. Results from a combination of scanning electron microscopy with energy dispersive X-ray spectroscopy and also powder X-ray diffraction, thermal analysis and Fourier transform infrared spectroscopy give an exceptionally full understanding of the mineralogy of these residues, which is discussed in the context of other results in the literature. The present work has shown that the bulk of the crystalline phases present in the investigated APC residues include Ca-based phases, such as CaCl{sub x}OH{sub 2−x}, CaCO{sub 3}, Ca(OH){sub 2}, CaSO{sub 4}, and CaO, as well as soluble salts, such as NaCl and KCl. Poorly-crystalline aragonite was identified by FTIR. Sulphur appears to have complex redox speciation, presenting as both anhydrite and hannebachite in some UK EfW APC residues. Hazardous elements (Zn and Pb) were widely associated with soluble Ca- and Cl-bearing phases (e.g. CaCl{sub x}OH{sub 2−x} and sylvite), as well as unburnt organic matter and aluminosilicates. Specific metal-bearing minerals were also detected in some samples: e.g., Pb present as cerussite; Zn in gahnite, zincowoodwardite and copper nickel zinc oxide; Cu in tenorite, copper nickel zinc oxide and fedotovite. Aluminium foil pieces were present and abundantly covered by fine phases, particularly in any cracks, probably in the form of Friedel’s salt.
The International Reactor Dosimetry File (IRDF)-2002 released in 2004 by the IAEA (see http://www-nds.iaea.org/irdf2002/) contains cross-section data and corresponding uncertainties for 66 dosimetry reactions. New cross-section evaluations have become available recently that re-define some of these dosimetry reactions including: (1) high-fidelity evaluation work undertaken by one of the authors (KIZ); (2) evaluations from the US ENDF/B-VII.0 and candidate evaluations from the US ENDF/B-VII.1 libraries that cover reactions within the International Evaluation of Neutron Cross-Section Standards; (3) European JEFF3.1 library; and (4) Japanese JENDL-4.0 library. Additional high-threshold reactions not included in IRDF-2002 (e.g., {sup 59C}o(n,3n) and {sup 209}Bi(n,3n)) have been also evaluated to characterize higher-energy neutron fields. Overall, 37 new evaluations of dosimetry reactions have been assessed and intercomparisons made with integral measurements in reference neutron fields to determine whether they should be adopted to update and improve IRDF-2002. Benchmark calculations performed for newly evaluated reactions using the ENDF/B-VII.0 {sup 235}U thermal fission and {sup 252}Cf spontaneous fission neutron spectra show that calculated integral cross sections exhibit improved agreement with evaluated experimental data when compared with the equivalent data from the IRDF-2002 library. Data inconsistencies or deficiencies of new evaluations have been identified for {sup 63}Cu(n,2n), {sup 60}Ni(n,p) {sup 60m+g}Co, {sup 55}Mn(n,{gamma}), and {sup 232}Th(n,f) reactions. Compared with IRDF-2002, the upper neutron energy boundary was formally increased from the actual maximum energy of typically 20 MeV up to 60 MeV by using the TENDL-2010 cross sections and covariance matrices. This extension would allow the updated IRDF library to be also used in fusion dosimetry applications. Uncertainties in the cross sections for all new evaluations are given in the form of relative covariance matrices. Newly evaluated excitation functions should be considered as suitable candidates in the preparation of an improved version of the IRDF that was planned to be released for testing in December 2011. (authors)