Numerical analysis and experimental validation of planar electrorefiner for spent nuclear fuel treatment using a tertiary model

To improve the uranium recovery rate in pyroprocessing, it is crucial to develop a planar-type electrorefiner. This can be achieved prior to actual experiments by using computer simulations to analyze the shape, arrangement, and size of the cathode. In this paper, tertiary-model-based computational analysis was performed on a planar-type electrorefiner. Flat-plate and rod-type cathodes were analyzed under constant-current condition; calculations were performed on high-efficiency-type electrodes with convection effects under the same conditions by comparing the dependence of the generated overpotential on the applied current. Analytic and experimental results were analyzed by comparing the electric potential of the plate-type device with that of a uranium electrorefiner while varying the arrangement of the electrodes.     

Pyrithyldione excretion in the urine. Methods and results from various collectives

A simple thinlayer chromatographic method for the detection of pyrithyldion in 5 ml of urine per analysis is described. Sensitivity (0.01 mug of pyrithyldion) and specificity (reaction still positive 5-6 days after injection of 50 mg of pyrithyldion) of the method are considered acceptable. The duration of elimination for pyrithyldion is relatively long (5-6 days). Epidemiological investigations were conducted in two different patient groups to analyze spontaneously voided urine samples. The incidence of positive urine samples in 204 ambulatory internal medicine patients was only 0.5% for pyrithyldion and N-acetyl-p-amino-phenol (the main metabolite of phenacetin). In contrast, the incidence in a specially selected group of 600 working women with regular intake of analgesics was much higher (between 17.7% and 28%) in the period 1969 to 1972.     

Running a Profitable Construction Company: Revisited Break-Even Analysis

Many companies have a tendency to spread out their operations into branches and∕or separate corporations. The construction industry is a good example. With work being slow in some areas, it is sometimes more profitable to spread out the company into different areas in order to absorb more work and therefore create branches to the main office. When this is done, it is important to centralize these branches and analyze them as a whole to help the corporation. In this process, the break-even analysis can be used to help analyze the operations. Consideration for a corporation having one or more branches involved in several projects takes time and teamwork. The team that is organized to help in the decision-making process needs a plan to determine how the project will affect the company and other jobs that are already in progress. With one corporation having two or more branches, it can be difficult to figure out where the company as a whole needs to be in order to turn a profit. The team must consider what each branch is doing in volume and what their break-even points are. This comes down to an important point of this research, which is “where to break even” before the profit consideration is made. This research provides an exemplary application of the break-even analysis to an actual construction company with one or more branches.     

Plastic ELISA-on-a-chip based on sequential cross-flow chromatography

A plastic chip that can perform immunoassays using an enzyme as signal generator, i.e., ELISA-on-a-chip, was developed by incorporating an immunostrip into channels etched on the surfaces of the chip. To utilize an analytical concept of cross-flow chromatography, the chip consisted of two cross-flow channels in the horizontal and vertical directions. In the vertical channel, we placed a 2-mm-wide immunostrip for cardiac troponin I (cTnI), which was identical to a conventional rapid test kit except for the utilization of an enzyme, horseradish peroxidase (HRP), as tracer. An enzyme substrate supply channel and a horizontal flow absorption pad compartment were transversely arranged on each lateral side of the signal generation pad of the strip, respectively. Upon application of a sample containing cTnI, it migrated vertically through the membrane strip by capillary action, and antigen-antibody binding occurred. After 15 min, the horizontal flow was initiated by the addition of a chromogenic substrate solution for HRP into the supply channel and by partial superimposition of the horizontal flow absorption pad onto the signal generation pad. A color signal proportional to the analyte concentration was produced on this pad, measured after 5 min as optical densities using a digital camera-based detector, and quantified by integration of the densities under the peak after normalization. Its calibration curve indicated that the detection limit of the chip was approximately 0.1 ng/mL and its quantification limit was 0.25 ng/mL. In measuring blindly prepared samples, the chip performance correlated with that of a reference system, Beckman Coulter Access, within 2.5-fold discrepancy at the detection limit.     

A study of carbon-nanotube-based nanoelectromechanical resonators tuned by shear strain

This paper has investigated, using a classical molecular dynamics simulation method based on the Tersoff-Brenner potential, the resonance-frequency changes of single-walled carbon-nanotube resonators originating from the purely mechanical response of single-walled carbon nanotubes. The tension decreased with increasing rotation angle, so the resonance frequencies could be changed by controlling the rotation angles of the single-walled carbon nanotubes. The resonance frequencies decreased with increasing angle, and when the rotation angle was greater than 60°, the changes were marked. For nanotubes of similar length, the bandwidth for the (3, 3) single-walled carbon nanotube was higher than for the (5, 0) single-walled carbon nanotube. Because properties arising from the shear-strain-induced tension response can affect the electromechanical behavior of carbon nanotubes, the shear-strain-induced tension response should be given serious consideration in the application of embedded carbon nanotubes in nanoelectromechanical systems.     

Optical and Dielectric Properties of Chalcogenide Glasses at Terahertz Frequencies

Terahertz time‐domain spectroscopy has been used to study the optical and dielectric properties of three chalcogenide glasses: Ge₃₀As₈Ga₂Se₆₀, Ge₃₅Ga₅Se₆₀, and Ge₁₀As₂₀S₇₀. The absorption coefficients α(ν), complex refractive index n(ν), and complex dielectric constants ?(ν) were measured in a frequency range from 0.3 THz to 1.5 THz. The measured real refractive indices were fitted using a Sellmeier equation. The results show that the Sellmeier equation fits well with the data throughout the frequency range and imply that the phonon modes of glasses vary with the glass compositions. The theory of far‐infrared absorption in amorphous materials is used to analyze the results and to understand the differences in THz absorption among the sample glasses.     

High-density screen of human tumor cell lines for homozygous deletions of loci on chromosome arm 8p

The purpose of this article is to describe a study that implemented concept maps as a methodology to teach and evaluate critical thinking. Students in six senior clinical groups were taught to use concept maps. Students created three concept maps over the course of the semester. Data analysis demonstrated a group mean score of 40.38 on the first concept map and 135.55 on the final concept map, for a difference of 98.16. The paired t value comparing the first concept map to the final concept map was -5.69. The data indicated a statistically significant difference between the first and final maps. This difference is indicative of the students' increase in conceptual and critical thinking.     

In-situ observation of a dendrite growth in an aqueous condition and a uranium deposition into a liquid cadmium cathode in an electrowinning system

A zinc-gallium system was setup to observe the growth process of dendrites and to compare the performance of the stirrers which would prevent a dendrite formation. In a no-stirring condition, zinc was easily deposited on a liquid gallium cathode in the form of dendrites. It was difficult for a paddle stirrer to directly fracture the zinc dendrites to fine particles. However, a harrow stirrer was observed to fracture the dendrite to some extent at high speeds. Not only their rotation speed but also the length of their blades needed to be properly adjusted to enhance their performance. In the uranium-cadmium experiment, the diffusion coefficient of the uranium species was obtained by the cyclic voltammetry method, which is around 1 × 10⁻⁵ cm²/s. In a no-stirring condition, most of the uranium deposited at the current densities of 35, 100 and 200 mA/cm² did not sink into the liquid cadmium cathode.     

Measurement method for profiling the residual stress and the strain-optic coefficient of an optical fiber

A method, believed novel, is demonstrated for determining the strain-optic coefficient profile as well as the residual-stress profile of an optical fiber by use of a modified polariscope combined with a fiber-elongation apparatus. Measurement results of the residual-stress and the strain-optic coefficient profiles for Ge-doped and Er-Ge-Al-doped optical fibers are demonstrated with this method.     

Li‐Rich Li[Li1/6Fe1/6Ni1/6Mn1/2]O2 (LFNMO) Cathodes: Atomic Scale Insight on the Mechanisms of Cycling Decay and of the Improvement due to Cobalt Phosphate Surface Modification

Lithium‐rich Li[Li_1/6Fe_1/6Ni_1/6Mn_1/2]O₂ (0.4Li₂MnO₃‐0.6LiFe_1/3Ni_1/3Mn_1/3O₂, LFNMO) is a new member of the xLi₂MnO₃·(1 ? x)LiMO₂ family of high capacity–high voltage lithium‐ion battery (LIB) cathodes. Unfortunately, it suffers from the severe degradation during cycling both in terms of reversible capacity and operating voltage. Here, the corresponding degradation occurring in LFNMO at an atomic scale has been documented for the first time, using high‐angle annular dark‐field scanning transmission electron microscopy (HAADF‐STEM), as well as tracing the elemental crossover to the Li metal anode using X‐ray photoelectron spectroscopy (XPS). It is also demonstrated that a cobalt phosphate surface treatment significantly boosts LFNMO cycling stability and rate capability. Due to cycling, the unmodified LFNMO undergoes extensive elemental dissolution (especially Mn) and O loss, forming Kirkendall‐type voids. The associated structural degradation is from the as‐synthesized R‐3m layered structure to a disordered rock‐salt phase. Prior to cycling, the cobalt phosphate coating is epitaxial, sharing the crystallography of the parent material. During cycling, a 2–3 nm thick disordered Co‐rich rock‐salt structure is formed as the outer shell, while the bulk material retains R‐3m crystallography. These combined cathode–anode findings significantly advance the microstructural design principles for next‐generation Li‐rich cathode materials and coatings.