Use of Polyaminocarboxylic Acids as Hydrophilic Masking Agents for Fission Products in Actinide Partitioning Processes

During the partitioning of trivalent actinides from High Active Raffinate (HAR) solutions, most processes have to cope with an undesirable co-extraction of some of the fission products. Four hydrophilic complexing agents of the group of polyaminocarboxylic acids, namely EDTA, HEDTA, DTPA, and CTDA were tested and compared for their ability to complex fission products in a simulated PUREX raffinate solution, thereby preventing their extraction into an organic solvent. Several solvents, based on TODGA and the DIAMEX reference molecule DMDOHEMA, that are commonly known to show quite high Zr and Pd co-extraction, were studied. Our investigations ultimately resulted in a substitution of oxalic acid and HEDTA by cyclohexanediaminetetraacetic acid (CDTA). A small addition of this hydrophilic complexing agent to the feed decreased the distribution ratios of Zr from 100 to <0.01. The suppression of Pd was also very effective, resulting in >90% of the metal retained in the feed solution. The extraction of trivalent actinides and lanthanides was not negatively affected by the presence of CDTA. Furthermore, experiments with high concentrations of Zr proved the applicability of this new masking agent. The suppression of Zr and Pd extraction was also verified at a high Pu loading which makes CDTA as a masking agent attractive for grouped actinide extraction processes (GANEX) as well as DIAMEX-SANEX type separations.     

Analysis of multiple cracks in thin coating on orthotropic substrate under mechanical and residual stresses

The analysis addresses a typical failure development pattern in thin films consisting of a system of multiple surface cracks leading to and branching along or near the interface between the film and the base material. The process is driven by thermal residual stresses and/or mechanical loading. Due to the high temperature gradients during the fabrication process, usually a net of surface cracks develops, which gives the appearance of a granular structure of the surface. A periodic array of parallel surface cracks is assumed. A “unit cell” or single cracked segment attached to the substrate is analyzed instead by assuming the channel cracks are spaced more or less uniformly and perfectly aligned in parallel in the transverse direction of the coating. The analysis is specialized to orthotropic and transversally isotropic materials. The problem is solved using FEM combined with the reciprocal theorem. Matched asymptotic procedure [Leguillon D, Sanchez-Palencia E. Computation of singular solutions in elliptic problems and elasticity. Paris: Masson; 1987; Vu-Quoc L, Tran VX. Singularity analysis and fracture energy-release rate for composites: piecewise homogenous-anisotropic materials. Comput Methods Appl Mech Engng 2006;195:5162-97] is used to derive the change of potential energy. Higher-order terms in the asymptotics are considered. The competition between penetration and debond for periodically distributed edge cracks especially near the critical value of the ratio of fracture spacing to the layer thickness is examined.     

Determining link weight system under various objectives for OSPF networks using a Lagrangian relaxation-based approach

An important traffic engineering problem for OSPF networks is the determination of optimal link weights. Certainly, this depends on the traffic engineering objective. Regardless, often a variety of performance measures may be of interest to a network provider due to their impact on the network. In this paper, we consider different objectives and discuss how they impact the determination of the link weights and different performance measures. In particular, we propose a composite objective function; furthermore, we present a Lagrangian relaxation-based dual approach to determine the link weight system. We then consider different performance measures and discuss the effectiveness of different objectives through computational studies of a variety of network topologies. We find that our proposed composite objective function with Lagrangian relaxation-based dual approach is very effective in meeting different performance measures and is computationally very fast.     

Interface Modifications of InAs Quantum‐Dots Solids and their Effects on FET Performance

InAs nanocrystals field‐effect transistors with an ON/OFF ratio of 10⁵ are reported. By tailoring the interface regions in the active layer step‐by‐step, the evolution of the ON/OFF ratio can be followed from approximately 5 all the way to around 10⁵. The formation of a semiconducting solid from colloidal nanocrystals is achieved through targeted design of the nanocrystal–nanocrystal interaction. The manipulation characteristics of the nanocrystal interfaces include the matrix surrounding the inorganic core, the interparticle distance, and the order of nanocrystals in the 3D array. Through careful analysis of device characteristics following each treatment, the effect of each on the physical properties of the films are able to be verified. The enhanced performance is related to interparticle spacing, reduction in sub‐gap states, and better electronic order (lower σ parameter). Films with enhanced charge transport qualities retain their quantum‐confined characteristics throughout the procedure, thus making them useful for optoelectronic applications.     

The Causes and Potential Injurious Effects of Elevated Serum Leptin Levels in Chronic Kidney Disease Patients

Leptin is an adipokine that regulates appetite and body mass and has many other pleiotropic functions, including regulating kidney function. Increased evidence shows that chronic kidney disease (CKD) is associated with hyperleptinemia, but the reasons for this phenomenon are not fully understood. In this review, we focused on potential causes of hyperleptinemia in patients with CKD and the effects of elevated serum leptin levels on patient kidney function and cardiovascular risk. The available data indicate that the increased concentration of leptin in the blood of CKD patients may result from both decreased leptin elimination from the circulation by the kidneys (due to renal dysfunction) and increased leptin production by the adipose tissue. The overproduction of leptin by the adipose tissue could result from: (a) hyperinsulinemia; (b) chronic inflammation; and (c) significant lipid disturbances in CKD patients. Elevated leptin in CKD patients may further deteriorate kidney function and lead to increased cardiovascular risk.     

Epigenetic Manipulation Induces the Production of Coumarin‐Type Secondary Metabolite from Arthrobotrys foliicola

Pursuing epigenetic manipulation approach in fungi led to the isolation of an unusual coumarin metabolite from fungi. An addition of the histone deacetylase inhibitor, suberohydroxamic acid (SBHA), to the culture medium of Arthrobotrys foliicola induced production of the coumarin‐type secondary metabolite represented by a single intensive peak in the HPLC profile of the ethyl acetate extract. The compound which was identified as 4‐ethyl‐7‐hydroxy‐8‐methyl‐2H‐chromen‐2‐one ( 1 ) was isolated from nature for the first time. Moreover, the investigation on the remaining part of the HPLC profile led to the separation of 6‐ethyl‐2,4‐dihydroxy‐3‐methylbenzaldehyde ( 2 ) and ten 2,5‐diketopiperazine compounds ( 3 – 12 ). The structures of isolates were deduced by their mass and NMR spectroscopic data. The coumarin‐type secondary metabolite ( 1 ) with peculiar smell induced by epigenetic stimulation is found for the first time in the Arthrobotrys species and the family Orbiliaceae. We evaluated 1 for the cytotoxic, anti‐inflammatory, anti‐allergic and nematocidal activities, however, it was found inactive.     

Unobtrusive vehicle motion prediction cues reduced simulator sickness during passive travel in a driving simulator

This study investigated cues that permit prediction of turns during passive movement through a virtual environment. Effects on simulator sickness (SS), presence and enjoyment were examined. Subjects were exposed to complex visual motion through a cartoon-like simulated environment in a driving simulator. Forward velocity remained constant and the motion path was the same across all experimental conditions. Using a within-subject design, we examined visual paths that provided different levels of cue salience - detailed, simplified and no cues - for the upcoming simulated vehicle motion. Following each trial, participants completed questionnaires on SS, presence and enjoyment. After all of the trials were completed, a debriefing determined participants' perceptions of vehicle motion attributes and their awareness of the prediction cues. The results showed that SS in the no-cue condition was significantly greater than that in the conditions that provided vehicle motion cues. Presence and enjoyment responses were not different across the conditions. No participants reported differences between prediction cue conditions or recognized that the vehicle motion followed the same path across trials. However, participants tended to report that the motion was smoother for the detailed-cue than the no-cue condition. Participants ranked turn predictability as higher in conditions with prediction cues. The results support the hypothesis that unobtrusive and unreported motion cues may alleviate SS in a virtual environment.     

$$hbox {TG}^2$$ TG 2 : text-guided transformer GAN for restoring document readability and perceived quality

International Journal on Document Analysis and Recognition (IJDAR) - Most image enhancement methods focused on restoration of digitized textual documents are limited to cases where the text...