High-throughput thermal plasma synthesis of FexCo1-x nano-chained particles with unusually high permeability and their electromagnetic wave absorption properties at high frequency (1-26 GHz).

Herein, we introduce novel 1-dimensional nano-chained FeCo particles with unusually-high permeability prepared by a highly-productive thermal plasma synthesis and demonstrate an electromagnetic wave absorber with exceptionally low reflection loss in the high-frequency regime (1-26 GHz). During the thermal plasma synthesis, spherical FeCo nanoparticles are first formed through the nucleation and growth processes; then, the high temperature zone of the thermal plasma accelerates the diffusion of constituent elements, leading to surface-consolidation between the particles at the moment of collision, and 1-dimensional nano-chained particles are successfully fabricated without the need for templates or a complex directional growth process. Systematic control over the composition and magnetic properties of FexCo1-x nano-chained particles also has been accomplished by changing the mixing ratio of the Fe-to-Co precursors, i.e. from 7 : 3 to 3 : 7, leading to a remarkably high saturation magnetization of 151-227 emu g-1. In addition, a precisely-controlled and uniform surface SiO2 coating on the FeCo nano-chained particles was found to effectively modulate complex permittivity. Consequently, a composite electromagnetic wave absorber comprising Fe0.6Co0.4 nano-chained particles with 2.00 nm-thick SiO2 surface insulation exhibits dramatically intensified permeability, thereby improving electromagnetic absorption performance with the lowest reflection loss of -43.49 dB and -10 dB (90% absorbance) bandwidth of 9.28 GHz, with a minimum thickness of 0.85 mm.

PD-L1 expression in paired biopsies and surgical specimens in gastric adenocarcinoma: A digital image analysis study.

Programmed death-ligand 1 (PD-L1) expression in biopsies of gastric carcinoma may predict the results in corresponding surgical specimens. We compared PD-L1 immunohistochemistry (IHC) 22C3 pharmDx expression in paired biopsy and resection specimens. We also characterized the validity of a new PD-L1 assay using digital image analysis. PD-L1 IHC with 22C3 pharmDx and clone 73-10 was performed in 224 gastric cancer tissues (112 biopsies and paired surgical tissues) and the specimens were analyzed with the Leica Aperio Imagescope. For statistical analyses, the area under the receiver operating characteristic curve and R package were used. With 22C3 pharmDx, a PD-L1 combined positive score of ≥1 was found in 36 biopsied (32.14 %) and 53 surgical (47.32 %) samples. PD-L1 expression results were concordant in 71 cases (63.4 %) and discordant in 41 (36.6 %). The overall discordance rate was 36.61 % (95 % confidence interval 2.101-8.983) and the κ value was 0.254 with fair agreement. The sensitivity and specificity of biopsy PD-L1 to predict the results of the surgical specimen was 62 % and 73 %, respectively. The correlation of 22C3 pharmDx and clone 73-10 was high (correlation coefficient = 0.88). When only tumor cell staining was compared, this correlation was increased (correlation coefficient = 0.95). Our results indicated moderate association of PD-L1 expression between gastric biopsies and corresponding resected tumors. Results of PD-L1 assay with 73-10 are comparable to 22C3 pharmDx results.

Solution-Processed Ferrimagnetic Insulator Thin Film for the Microelectronic Spin Seebeck Energy Conversion.

The longitudinal spin Seebeck effects with a ferro- or ferrimagnetic insulator provide a new architecture of a thermoelectric device that could significantly improve the energy conversion efficiency. Until now, epitaxial yttrium iron garnet (YIG) films grown on gadolinium gallium garnet (GGG) substrates by a pulsed laser deposition have been most widely used for spin thermoelectric energy conversion studies. In this work, we developed a simple route to obtain a highly uniform solution-processed YIG film and used it for the on-chip microelectronic spin Seebeck characterization. We improved the film roughness down to ∼0.2 nm because the extraction of thermally induced spin voltage relies on the interfacial quality. The on-chip microelectronic device has a dimension of 200 µm long and 20 µm wide. The solution-processed 20 nm thick YIG film with a 10 nm Pt film was used for the spin Seebeck energy converter. For a temperature difference of Δ T ≈ 0.036 K applied on the thin YIG film, the obtained Δ V ≈ 28 µV, which is equivalent to SLSSE ≈ 80.4 nV/K, is close to the typical reported values for thick epitaxial YIG films. The temperature and magnetic field-dependent behaviors of spin Seebeck effects in our YIG films suggest active magnon excitations through the noncoherent precession channel. The effective SSE generation with the solution-processed thin YIG film provides versatile applications of the spin thermoelectric energy conversion.

Protection effect of ZrO2 coating layer on LiCoO2 thin film fabricated by DC magnetron sputtering.

Bare and ZrO2-coated LiCoO2 thin films were fabricated by direct current magnetron sputtering method on STS304 substrates. Deposited both films have a well-crystallized structure with (003) preferred orientation after annealing at 600 degrees C. The ZrO2-coated LiCoO2 thin film provide significantly improved cycling stability compared to bare LiCoO2 thin film at high cut-off potential (3.0-4.5 V). The improvement in electrochemical stability is attributed to the structural stability by ZrO2 coating layer.