The ability of large-grain (RE)Ba2Cu3O7−δ ((RE)BCO; RE = rare earth) bulk superconductors to trap magnetic fields is determined by their critical current. With high trapped fields, however, bulk samples are subject to a relatively large Lorentz force, and their performance is limited primarily by their tensile strength. Consequently, sample reinforcement is the key to performance improvement in these technologically important materials. In this work, we report a trapped field of 17.6 T, the largest reported to date, in a stack of two silver-doped GdBCO superconducting bulk samples, each 25 mm in diameter, fabricated by top-seeded melt growth and reinforced with shrink-fit stainless steel. This sample preparation technique has the advantage of being relatively straightforward and inexpensive to implement, and offers the prospect of easy access to portable, high magnetic fields without any requirement for a sustaining current source.

https://iopscience.iop.org/article/10.1088/0953-2048/27/8/082001/pdf

A trapped field of 17.6 T in melt-processed, bulk Gd-Ba-Cu-O reinforced with shrink-fit steel

https://cyberleninka.org/article/n/685363.pdf

Pharmacokinetic aspects of retinal drug delivery.

This review encompasses definitions, classification, main properties, and application of polymer hydrogels. Raw materials and preparation techniques of polymer hydrogels were described. The factors that affect absorption capacity and swelling properties of polymer hydrogels were reviewed. PHG materials are defined as a viscoelastic network structure, swellable and not soluble in water with high absorbent capacity, which may reach 1000 g/g of their dried weight to be termed “superabsorbent polymer hydrogels”. PHGs have the ability to release absorbed fluids under certain circumstances.

Polymer Hydrogels: A Review

Numerical modeling of superconductors is widely recognized as a powerful tool for interpreting experimental results, understanding physical mechanisms, and predicting the performance of high-temperature-superconductor (HTS) tapes, wires, and devices. This is particularly true for ac loss calculation since a sufficiently low ac loss value is imperative to make these materials attractive for commercialization. In recent years, a large variety of numerical models, which are based on different techniques and implementations, has been proposed by researchers around the world, with the purpose of being able to estimate ac losses in HTSs quickly and accurately. This paper presents a literature review of the methods for computing ac losses in HTS tapes, wires, and devices. Technical superconductors have a relatively complex geometry (filaments, which might be twisted or transposed, or layers) and consist of different materials. As a result, different loss contributions exist. In this paper, we describe the ways of computing such loss contributions, which include hysteresis losses, eddy-current losses, coupling losses, and losses in ferromagnetic materials. We also provide an estimation of the losses occurring in a variety of power applications.

Computation of Losses in HTS Under the Action of Varying Magnetic Fields and Currents

Polymeric hydrogels for novel contact lens-based ophthalmic drug delivery systems: A review

Azulene incorporation and release by hydrogel containing methacrylamide propyltrimenthylammonium chloride, and its application to soft contact lens

PURPOSE The purpose of this study was to investigate the uptake and the release of antibiotics from a newly synthesized drug delivery hydrogel soft contact lens (SCL) using an ion ligand mechanism. METHODS The antibiotics used were Gatifloxacin (GFLX) and Moxifloxacin (MFLX). The uptake amount and the sustained-release kinetics of antibiotics were investigated in vitro, and were also compared with newly synthesized SCLs, etafilcon A and polymacon. The antibiotic concentrations in the cornea, aqueous humor, and crystalline lens, and the effect against bacterial proliferation were investigated in vivo using rabbit subjects. Additionally the drug release efficacy of the new SCL was compared with that of eye drop administrations. RESULTS In vitro, antibiotic uptake was increased with the weight percent (wt%) of the anionic group, and the released amount of antibiotics was highest during the initial 1 hour period, which then decreased over the next 72 hours. The released antibiotics volume of the new SCLs was significantly higher throughout 72 hours than that of the other two materials, etafilcon A and polymacon (P < 0.01). Whereas in vivo, the concentrations found in the cornea and aqueous humor were higher than those for the eye drop groups (P < 0.05 or P < 0.01). Antibiotic release at those sites decreased over 72 hours. No bacterial populations were detectable in the group treated with the new SCL presoaked in antibiotics throughout the experimental periods. CONCLUSIONS The new SCLs released the antibiotics over several days, and showed improved penetration into the eye, along with prevention of bacterial proliferation.

Development and efficacy of a drug-releasing soft contact lens.

Dispersed generators are being introduced to power systems to secure the electric power supply. However, a short-circuit capacity of the power system increases with the introduction of dispersed generators. As a result, there is concern that a fault current will increase further, and instantaneous voltage sag might be caused. It is proposed to apply a superconducting fault current limiter in the distribution system with dispersed generators to solve these issues. In this paper, the effect of superconducting fault current limiter in this power system is studied by the analysis with EMTP and the confirmation test is conducted with a simulator.

Study on the Effect of Fault Current Limiter in Power System With Dispersed Generators

Numerical studies on AC loss characteristic of a assembled conductors of multiple HTS tapes with high aspect ratio simulating YBCO tape in polygonal arrangement were presented in this paper. We developed a numerical model to analyze the AC loss in the HTS tape in the polygonally assembled conductor based on our previously developed model. The relations between the geometrical configuration and the AC loss properties of the conductor were made clear by the numerical simulation. The numerical results give the important information for the design of the cable conductor assembled by the HTS tapes with high aspect ratio such as YBCO tapes

Numerical Analysis of AC Loss Characteristics of Cable Conductor Assembled by HTS Tapes in Polygonal Arrangement

The magnetic field distributions of an HTS bulk magnet system were precisely measured between the face-to-face 34-T magnetic poles After the activation by 5-T field cooling magnetization, the magnetic flux density has reached the value of 226 T at the center of the 34-mm gap The sum of the local magnetic fields generated from each magnetic pole coincides with the local field strength in the gap We estimated the homogeneity of the magnetic flux densities of Bz and By, which were measured at various positions along z and y-axes in the center portion of the 60-mm gap Since the magnetic flux density becomes smooth with increasing distance, we obtained the smallest distribution range of 123 ppm of Bz = 162 T at the center of the gap as for Bz On the other, as for By, the smallest distribution range of 1125 ppm of Bz = 120 T was obtained at z = 17 mm distant from the center point Since there must exist a certain plane which has no vector components along the radius direction at the center of the gap, the closer the z-positions come to the null point, the more homogeneous the field distribution becomes

Takao Sato

Papers

Azulene incorporation and release by hydrogel containing methacrylamide propyltrimenthylammonium chloride, and its application to soft contact lens

Development and efficacy of a drug-releasing soft contact lens.

Study on the Effect of Fault Current Limiter in Power System With Dispersed Generators

Numerical Analysis of AC Loss Characteristics of Cable Conductor Assembled by HTS Tapes in Polygonal Arrangement

Strong Magnetic Field Generator Containing HTS Bulk Magnets and Compact Refrigerators