Self-assembled organic molecules can potentially be an excellent source of charge and spin for two-dimensional (2D) atomic-layer superconductors. Here we investigate 2D heterostructures based on In atomic layers epitaxially grown on Si and highly ordered metal-phthalocyanine (MPc, M = Mn, Cu) through a variety of techniques: scanning tunneling microscopy, electron transport measurements, angle-resolved photoemission spectroscopy, X-ray magnetic circular dichroism, and ab initio calculations. We demonstrate that the superconducting transition temperature (T) of the heterostructures can be modified in a controllable manner. Particularly, the substitution of the coordinated metal atoms from Mn to Cu is found to reverse the T shift from negative to positive directions. This distinctive behavior is attributed to a competition of charge and spin effects, the latter of which is governed by the directionality of the relevant d-orbitals. The present study shows the effectiveness of molecule-induced surface doping and the significance of microscopic understanding of the molecular states in these 2D heterostructures.

A proper understanding on the charge mobility in organic materials is one of the key factors to realize highly functionalized organic semiconductor devices. So far, however, although a number of studies have proposed the carrier transport mechanism of rubrene single crystal to be band-like, there are disagreements between the results reported in these papers. Here, we show that the actual dispersion widths of the electronic bands formed by the highest occupied molecular orbital are much smaller than those reported in the literature, and that the disagreements originate from the diffraction effect of photoelectron and the vibrations of molecules. The present result indicates that the electronic bands would not be the main channel for hole mobility in case of rubrene single crystal and the necessity to consider a more complex picture like molecular vibrations mediated carrier transport. These findings open an avenue for a thorough insight on how to realize organic semiconductor devices with high carrier mobility.

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The bore expansion tests of a mild steel sheet and two types of high-strength steel sheets using conical-and flat-headed punches are simulated using the dynamic explicit finite element program LS-DYNA ver. 970 with shell elements. The ductile fracture criterion proposed by Cockcroft and Latham is applied to the prediction of the forming limit in bore expansion processes. In our previous studies, the fracture strains derived from the criterion gave the best fit to the experimental results in biaxial stretching. The comparison of the simulation results with the experimental results in this study shows the possibility of forming limit prediction via the present approach in which we take the work hardening and damage in the blanking process of the bore into consideration.

Moderately halophilic strain DT-W was isolated from the mud of the Mariana Trench. Cells of the organism were rod-shaped (1.5-2  µm x 0.5-0.8 µm) with some flagella extruding from the cells. Growth occurred in an NaCl concentration of about 0.1-15% (optimal: 3-5%), at pH of 6-9, and at temperatures ranging from 4-51 °C (optimal: 30-37 °C). The results of 16S rDNA analysis and DNA-DNA hybridization analyses showed that DT-W was closely related to Halomonas aquamarina, Halomonas axialensis and Halomonas meridiana. Furthermore, additional physiological properties and the cytochrome contents of DT-W were also analyzed.