Dendrite-free Li deposition using trace-amounts of water as an electrolyte additive
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Qian, Jiangfeng↗
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Experimental studies for the detection of protein in trace amounts
Organic cyanine dye for detection of protein in trace amounts - dye reaction mechanism, methods of eliminating inorganic compound reaction with dye, and detection of humic acid
STOICHIOMETRY↗
Ultrasonication-assisted trace amount solvent synthesis of Cs 4 PbBr 6 crystal with ultra-bright green light emission
Cs 4 PbBr 6 crystals have been synthesized by an ultrasonication-assisted trace amount polar solvent method. The prepared green Cs 4 PbBr 6 material was found to have high photoluminescence (PL) brightness and 10 ns PL lifetime. The prepared green light emitting device can achieve the maximum brightness of 3.8 × 10 9 cd/m 2 , which is nearly 100 times higher than a wick. The white light emitting device based on Cs 4 PbBr 6 crystals has better performance than commercial products, which can cover 32.3% of the color gamut and achieves 107.3% coverage for International Commission on Illumination (CIE)1931 and 84.8% coverage for CIE1976.
36 MATERIALS SCIENCE↗
Enhanced electrocatalytic activity and stability of Pd 3 V/C nanoparticles with a trace amount of Pt decoration for the oxygen reduction reaction
In this study, carbon supported Pd 3 V bimetallic alloy nanoparticles (Pd 3 V/C) have been successfully synthesized via a simple impregnation–reduction method, followed by high temperature treatment under a H 2 atmosphere. Electrochemical tests reveal that the half-wave potential of Pd 3 V/C-500 shifts positively 40 mV compared with Pd/C. However, the catalytic activity of Pd 3 V/C-500 suffers from serious degradation after 1k cycles. By a spontaneous displacement reaction or co-reduction method, a trace amount of Pt was decorated on the surface or inside of the Pd 3 V/C nanoparticles. The catalytic activity and stability of the Pd 3 V@Pt/C and Pt-Pd 3 V/C catalysts for the oxygen reduction reaction (ORR) are enhanced significantly, and are comparable to commercial Pt/C. In addition, the Pt mass activity of Pd 3 V@Pt/C and Pt-Pd 3 V/C improves by factors of 10.9 and 6.5 at 0.80 V relative to Pt/C. Moreover, Pt-decorated Pd 3 V/C nanoparticles show almost no obvious morphology change after durability tests, because the Pt-rich shell plays an important role in preventing degradation.
36 MATERIALS SCIENCE↗
Suppressing ion migration in metal halide perovskite via interstitial doping with a trace amount of multivalent cations
Cations with suitable sizes to occupy an interstitial site of perovskite crystals have been widely used to inhibit ion migration and promote the performance and stability of perovskite optoelectronics. However, such interstitial doping inevitably leads to lattice microstrain that impairs the long-range ordering and stability of the crystals, causing a sacrificial trade-off. Here, we unravel the evident influence of the valence states of the interstitial cations on their efficacy to suppress the ion migration. Incorporation of a trivalent neodymium cation (Nd 3+ ) effectively mitigates the ion migration in the perovskite lattice with a reduced dosage (0.08%) compared to a widely used monovalent cation dopant (Na + , 0.45%). As a result, the photovoltaic performances and operational stability of the prototypical perovskite solar cells are enhanced with a trace amount of Nd 3+ doping while minimizing the sacrificial trade-off.
36 MATERIALS SCIENCE↗
Removal of Trace Amounts of Co-60 from NPP Waste Water Using UV-C Irradiation, TiO{sub 2} and Co-Treat Inorganic Ion Exchange Media - 16025
The removal of Co-60 from an aqueous nuclear liquid waste obtained from a BWR NPP was tested using a two-step process. In the first phase the liquid waste was oxidized with ultraviolet irradiation at 254 nm (UV-C irradiation) together with a photo-catalyst, TiO{sub 2} P25 AEROXIDE, to degrade the organic complexing agents present in the solution. During some of the experiments it was noticed that TiO{sub 2} P25 AEROXIDE also removed Co-60 from the solution. In the second phase the UV-C irradiated solution was mixed with inorganic ion exchange media, Co-Treat, to remove the rest of Co-60 from the solution. The effect of pH and contact time with UV-C irradiation were evaluated and both had a noticeable effect on the results. Best results were attained when pH of the initial test solution was lowered to 3.5 ± 0.2 before the UV-C irradiation. From the initial Co-60 activity, 2.2 Bq/ml, the activity decreased to 0.03 ± 0.01 Bq/ml after 24 hours of UV-C irradiation together with the photo-catalyst and mixing with Co-Treat. (authors)
12 MANAGEMENT OF RADIOACTIVE AND NON-RADIOACTIVE W↗
Effect of trace amounts of added Sc on microstructure and mechanical properties of 2055 aluminum alloy
Highlights: • Effect of trace Sc on microstructure and mechanical properties in 2055 Al-alloy was investigated. • T{sub 1} is the main strengthening phase in Sc free and Sc added 2055 alloy at the aging temperature of 175°C and 200°C. • The refinement of T{sub 1} by Sc addition depends on the aging temperature. • Mechanical properties were deteriorated by Sc at the aging temperature of 175°C and improved at 200°C aging treatment. - Abstract: The effects of Sc additions and isothermal aging on the microstructure and mechanical properties of 2055 aluminum alloy have been investigated. The isothermal aging temperatures investigated were 175 °C and 200 °C. Results show that the aging temperature does not affect the type of precipitates in both Sc-free and Sc-added 2055 Al alloys. While remarkable changes in the size and number density of T{sub 1} (Al{sub 2}CuLi) precipitates have been observed. For samples aged at 175 °C for 8 h, the average length of T{sub 1} precipitates was increased from 39.9 nm to 45.6 nm, the number density decreased from 5.77 × 10{sup 22} m{sup −3} to 3.68 × 10{sup 22} m{sup −3} after Sc addition. On the contrary, when samples were aged at 200 °C for 8 h, the length decreased from 59.89 nm to 43.32 nm and number density increased from 2.13 × 10{sup 22} m{sup −3} to 3.00 × 10{sup 22} m{sup −3} by adding trace Sc. Slight deterioration of tensile strength and yield strength with higher ductility was founded at the aging temperature of 175 °C for 8 h due to the larger size and lower number density of T{sub 1} precipitates along with the formation of a W (AlCuSc) phase during the casting or homogenization processes. When aging temperature increased to 200 °C, tensile strength and yield strength were significantly improved by Sc addition without losing ductility. Highly dense fine T{sub 1} precipitates take responsible for the strength improvement, and to some extent it compensated the strength loss caused by the formation of W phase. A “vacancy-prison” mechanism was adopted to explain the effect of Sc additions on the precipitation of T{sub 1} phase as a function of aging temperature.
36 MATERIALS SCIENCE↗
Experimental Studies for the Detection of Protein in Trace Amounts Quarterly Status Report, 1 Mar. - 31 May 1965
Methods for separating inorganic compounds from organic materials in investigation of trace proteins in soils
INORGANIC COMPOUND↗
Atomic rearrangement from disordered to ordered Pd-Fe nanocatalysts with trace amount of Pt decoration for efficient electrocatalysis
The structure-activity relationship between the ORR performance and the surface electronic structure of Pd is constructed and the ORR performance are rationally modified via the structural transition from disordered face centered cubic phase (fcc, D-PdFe/C) to ordered intermetallic tetragonal phase (fct, O-PdFe/C). When the small amount of Pt atoms decorated on O-PdFe/C surface forming O-PdFe@Pt/C core-shell structure, the sublayer of Pd and Fe atoms may cause the lattice contraction of surface Pt and then weak the bonding energy on O-PdFe@Pt/C catalyst relative to bulk Pt/C, which is further illustrated by density functional theory (DFT) calculation. The weakened oxygen affinity results in the enhancement of ORR performance on O-PdFe@Pt/C. Here, for a practical application, the well-constructed O-PdFe@Pt/C exhibits higher voltage and peak power density than D-PdFe@Pt/C and Pt/C when applied as the air-breathing cathode material in Zn-air battery.
25 ENERGY STORAGE↗
Inhibition of Reaction Layer Formation on MgO(100) by Doping with Trace Amounts of Iron
Despite extensive research on MgO’s reactivity in the presence of CO 2 under various conditions, little is known about whether impurities incorporated into the solid, such as iron, enhance or impede hydroxylation and carbonation reactions. The purity of the MgO required for the successful implementation of MgO looping as a direct air capture technology affects the deployment costs. With this motivation, we tested how incorporated iron impacts MgO (100) reactivity and passivation layer formation under ambient conditions by using atomic force microscopy, electron microscopy, and synchrotron-based X-ray scattering. Based on electron microprobe analysis, our MgO samples were 0.5 wt % iron, and Mössbauer spectroscopy results indicated that 70% of the iron is present as Fe(II). We find that even these low levels of iron dopants impeded both the hydroxylation at various relative humidities (10%, 33%, 75%, and >95%) and carbonation in CO 2 (33%, 75%, and >95%) on the (100) surface. Crystalline reaction products were formed. Reaction layers on the sample were easily removed by exposing the sample to deionized water for 2 min. Overall, our findings demonstrate that the presence of iron dopants slows the reaction rate of MgO, indicating that MgO without incorporated iron is preferable for mineral looping applications.
37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗
Performance characteristics of a thermionic converter with a /110/ tungsten emitter and a collector of niobium with trace amounts of tungsten and niobium carbide on the surface
Comparison of thermionic tungsten /110/ converter performances with niobium collectors and nickel collectors at various emitter, collector and cesium reservoir temperatures
Podkulski, S. P.↗
Determination of trace amounts of POF3
Approach takes advantage of fact that phosphorous oxyfluoride (POF3) and phosphorous oxychloride (POC13) both belong to same molecular symmetry group and should have extinction coefficients that are approximately the same. Extinction coefficient of reagent-grade POC13 is measured, and this coefficient is employed to calculate POF3 concentrations.
Foster, J. N.↗
A new highly enriched 233 U reference material for improved simultaneous determination of uranium amount and isotope amount ratios in trace level samples
A highly-enriched 233 U reference material (>0.99987 n( 233 U)/n(U)) has been prepared and characterized for use as an isotope dilution mass spectrometry spike. An ion exchange separation was performed on 1 g of high purity 233 U to further reduce trace amounts of contaminant Pu in the material. The purified 233 U was then prepared as a master solution which was analyzed for molality of uranium by modified Davies and Gray titration. A portion of the master solution was quantitatively diluted and dispensed for reference material units. Selected units were analyzed for verification of uranium amount and to characterize uranium isotope amount ratios by multi-collector inductively couple plasma mass spectrometry. Furthermore, modelling of spike-corrected isotopic data show that the new spike will enable simultaneous measurements of uranium amount and isotope amount ratios with resulting uncertainties that are substantially less sensitive to over spiking than widely used 233 U certified reference materials.
233U↗
Hydrocyclone/Filter for Concentrating Biomarkers from Soil
The hydrocyclone-filtration extractor (HFE), now undergoing development, is a simple, robust apparatus for processing large amounts of soil to extract trace amounts of microorganisms, soluble organic compounds, and other biomarkers from soil and to concentrate the extracts in amounts sufficient to enable such traditional assays as cell culturing, deoxyribonucleic acid (DNA) analysis, and isotope analysis. Originally intended for incorporation into a suite of instruments for detecting signs of life on Mars, the HFE could also be used on Earth for similar purposes, including detecting trace amounts of biomarkers or chemical wastes in soils.
Ponce, Adrian↗
Column amounts of trace gases from ground based FTIR measurements in the late north polar winters 1990 and 1991
Two FTIR spectrometers were employed in the late winters 1990 and 1991 in Esrange, North Sweden, and in Ny Aalesund, Spitsbergen to detect zenith column amounts of several trace gases. Time series of column amounts of the trace gases O3, N2O, CH4, HNO3, NO2, CHl, and HF have been derived from the measured spectra. Additionally, some information on the vertical distribution of HCl could be obtained by analyzing the spectral line shapes. The results are interpreted in terms of dynamical and chemical processes.
Adrian, Gabriele↗
Electronic and Steric Influences of Pendant Amine Groups on the Protonation of Molybdenum Bis(dinitrogen) Complexes
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bio-inspired↗
Competitive grain boundary segregation of phosphorus and carbon governs delamination crack in a ferritic steel
Highlights: • Trace amounts of P in the steel cause delamination in case of Lt-high Temp. holding. • Anisotropic microstructure did not affect the delamination in this study. • Crack-linked GBs in Lt-high Temp. steel had higher P and lower C segregation. • Crack-interrupt GBs in St-high Temp. steel had lower P and higher C segregation. • Competitive segregation controlled by high Temp. holding time affects delamination. - Abstract: The present study aims at unveiling the influence of trace amounts of phosphorus on the macro-scale delamination in a ferritic steel. Two different steels with trace amounts of phosphorus were examined to reveal the cause: One was made by long-time high temperature holding to maximize the phosphorus segregation, and the other one was made by short-time high temperature holding to minimize the phosphorus segregation. The atom probe results at the grain boundaries ahead of the delamination-related cracks provide a strong evidence that phosphorus-enrichment and carbon-depletion for the long-time high temperature holding induces a larger degree of delamination as compared to the short-time high temperature holding. Reasons for the different segregation tendency were discussed by correlating the isothermal holding time at high temperature and the competitive segregation between phosphorus and carbon.
36 MATERIALS SCIENCE↗