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This dataset contains time-series data of TEM images and synchronous properties of five Au-NC samples under various combined manipulations, such as pulling, pushing, or shearing. In the experiment for each sample, two Au tips with diameter of 10 μm were attached to one end of a length extension resonator (LER) and the counter electrode, respectively. Thereafter, the Au-NC samples were fabricated by contacting the ends of the two wires by changing the position of the LER through the piezo actuator and a micrometer that coarsely changed the position of the piezo actuator. Au-NCs were formed between two tapered Au bases. The electrical conductance and spring constant of the Au-NCs were sampled simultaneously at a rate of 2.4 kHz. The fabricated Au-NCs were observed in-situ using an ultra-high vacuum TEM (JEM-2000VF, JEOL) at an accelerating voltage of 200 kV. The pressure at the TEM column was maintained below 2x10-6 Pa to avoid contamination by the Au NCs. Consequently, TEM images were captured using a charge-coupled device (CCD) camera at a rate of 30 Hz. Given the sampling rates of the TEM (30 Hz) and the mechanical response (2.4 kHz), each recorded TEM image was synchronized to a time-series window of 80 values of the recorded mechanical responses. Contained within this dataset are raw video recordings documenting experiments performed on gold nano-contacts, in conjunction with the associated processed data that is essential for the training of models within our analytical framework. Specifically, the processed data encompasses sequences of background-removed video footage earmarked for subsequent nano-contact region detection. The segmented nano-contact region images extracted from these sequences serve as the basis for training the generative model. Concurrently, the structural features corresponding to these regions are employed in the training of our property prediction models. In the following, there are detailed description of the files uploaded: "Raw.zip" contains the raw video recordings documenting experiments performed on gold nano-contacts. "Background_Removal.zip" contains videos processed with background removal and csv files recording measurements of electrical conductance G and elastic spring constant k. "Train_Data.zip" contains the structural features of the nano-contacts for training predictive model and images of segmented nano-contacts for training generative model. Detailed description can be found in [1], [2]., {"references":["K. Ishizuka, M. Tomitori, T. Arai, and Y. Oshima, Applied Physics Express 13 (2020).","J. Zhang, K. Ishizuka, M. Tomitori, T. Arai, and Y. Oshima, Nanotechnology 31, 205706 (2020)."]}

The dataset shows SmFe12-based crystalline magnetic materials under the formula SmFe12-a-bXaYb with X and Y as the substituted elements from Mo, Zn, Co, Cu, Ti, Al, and Ga; a and b are integer numbers of X and Y compositions, respectively and under restriction a+ba iron sites with element X and b iron sites with element Y. The formation energy and magnetization per atom of each structure are estimated from the Vienna ab initio simulation package (VASP) [1]. The optimization process for VASP follows the Open Quantum Materials Database standard [2]. The formation energy and magnetization are estimated with reference from [3]. Details discussion about the dataset are shown in the paper "Nguyen, DN., Kino, H., Miyake, T. et al. Explainable active learning in investigating structure–stability of SmFe12-α-βXαYβ structures X, Y {Mo, Zn, Co, Cu, Ti, Al, Ga}. MRS Bulletin (2022). https://doi.org/10.1557/s43577-022-00372-9" [1] VASP: Vienna Ab initio Simulation Package: https://www.vasp.at/. [2] OQMD: Open Quantum Materials Database: http://www.oqmd.org/. [3] Journal of Applied Physics 120, 203904 (2016); https://doi.org/10.1063/1.4968798, This work was supported by the Ministry of Education, Culture, Sports, Science and Technology of Japan (MEXT) ESICMM Grant Number 12016013 and "Program for Promoting Researches on the Supercomputer Fugaku" (DPMSD, Grant No. JPMXP1020200307), JSPS KAKENHI Grants Number 20K05301 and Number JP19H05815 (Grant-in-Aid for Scientific Research on Innovative Areas "Interface Ionics") and JSPS KAKENHI Grants Number 21K14396 (Grant-in-Aid for Early-Career Scientists).

We extended the decision tree and frequent itemset mining to find the separated distribution condition in the magnetocrystalline anisotropy of films using an exhaustive search method. We also perfo...

Distorted cubane [Mn4+Mn33+(μ3-L2-)3(μ3-X-)(Z)3-(dbm)3-] ( L=O; X=various; Z=(OAc)3; dbmH=dibenzoyl-methane) single-molecule magnets (SMMs) have been studied by first-principles calculations. Our earlier studies showed that the basic mechanism of antiferromagnetic Mn4+-Mn3+ coupling (JAB) is determined by the π type hybridization among the dz2 orbitals at the Mn3+ sites and the t2g orbitals at the Mn4+ site through the p orbitals at the μ3-L2- ions. This result allows us to predict that ferrimagnetic structure of Mn4+Mn33+ molecules will be the most stable with the Mn4+-(μ3-L2-)-Mn3+ angle α ≈ 90° , while synthesized Mn4+Mn33+ molecules have α ≈ 95°. One approach is suggested to design new Mn4+Mn33+ SMMs having a much more stable ferrimagnetic state. This approach is controlling the Mn4+-(μ3-L2-)-Mn3+ exchange pathways by rational variations in ligands to strengthen the hybridization between Mn ions. In this paper, by combining variations in the L and Z ligands, ten new high-spin [Mn4+Mn33+(μ3-L2-)3(μ3-F-)3(Z)3-(CH(CHO)2)3-] ( L=NCGeH5, NGeCH5, NGe2H5, NSiGeH5, or NGeSiH5; Z=(OAc)3 or MeC(CH2NCOMe)3 ) molecules have been designed. Our calculated results show that these ten modelling Mn4 molecules have α ≈ 90° and JAB/kB in the range of (-231.6, -147.4) K, in which the molecule with [L,Z]=[NCGeH5,MeC(CH2NCOMe)3] has the highest JAB/kB of - 231.6 K corresponding to α = 89.23°. This value is over 3 times larger than that of synthesized Mn4 SMMs. Our calculated results demonstrate combining variations in the L and Z ligands as an effective way to tailor intramolecular exchange coupling of the Mn4 molecules. The results would give some hints for synthesizing new SMMs.

We have synthesized novel Mussel-mimetic adhesive resin from biomass monomers. Because the adhesive resin contains catechol groups at its chain ends, which is similar to the chemical structure of 3,4-dihydroxyphenyl-L-alanine, produced by Mussel, it demonstrates strong adhesive characteristics onto organic and/or inorganic surfaces beyond those of the conventional instant superglue. The origin of this strong adhesive characteristic was attributed to strong hydrogen bond interaction between our new resins and oxidized and/or OH groups on the substrates. We have synthesized novel Mussel-mimetic adhesive resin from biomass monomers. Because the adhesive resin contains catechol group at their chain ends, which is similar chemical structure of 3,4-dihydroxyphenyl-L-alanine (DOPA) produced by Mussel, it demonstrated strong adhesive characteristics onto organic and/or inorganic surfaces beyond the conventional instant superglue as shown in figures (X, conventional instant superglue; Y, poly(DHCA-co-4HCA) resin). The origin of this strong adhesive characteristic was discussed by strong type of hydrogen bond interaction between our new resins and oxidized and/or OH group on the substrates.

What is structure of water surrounding proteins remains as one of fundamental unsolved problems of science. Methods in biophysics only provide qualitative description of the structure and thus clarifying the collective phenomena of a huge number of water molecules is still beyond intuition in biophysics. We introduce a simulation-based data mining approach that quantitatively model the structure of water surrounding a protein as clusters of water molecules having similar moving behavior. The paper presents and explains how the advances of AI technique can potentially solve this challenging data-intensive problem.

This paper discusses the knowledge transfer process in offshore outsourcing. The focus is a case study of software offshore outsourcing from Japan to Vietnam. Initial results confirm that willingness to cooperate and good impressions facilitate the knowledge transfer process. In addition, communication barriers, cultural differences, lack of equivalence in individual competence, and lack of common rules slow down the transfer process. The study also identifies the Bridge System Engineer (Bridge SE)-a type of coordinator who mediates and enhances the relationship between Japanese clients and Vietnamese service providers. Employing a Bridge SE is an effective way to fill the communication gap, the cultural gap, and generally improve the business relationship. Bridge SEs use their background of higher education and long-term residence in Japan to give advice to Vietnamese software teams on Japanese cultural characteristics, such as the apology culture and the separation between work and private time. In other situations, Bridge SEs use their IT background and communication skills to verify and adjust communication contents before information is sent from one side to another.

Adsorptions of hydrogen, oxygen and carbon monoxide molecules on surfaces of single wall carbon nanotubes (SWNTs) and graphene adhered by a Pt atom have been investigated by density functional theory calculation (DFT). Our calculations show that the Pt adatom significantly promotes the physisorption of hydrogen in a region around it with radius of about 5 A. The physisorption configuration in which oxygen molecule aligned parallelly to the surfaces of SWNTs and graphene are most preferred. In contrast, both of the physisorption configurations in which CO molecule aligned parallelly and perpendicularly with the carbon end towards the graphene and SWNTs surfaces were preferred. The obtained results suggested that the modification of the electronic structure by adhesion of Pt atom on surfaces of the support materials can modify their physisorption properties of gas molecules.

The molecular structures and vibration modes of cyclopentasilane (Si 5 H 10 ) have been examined by employing ab initio and density-functional methods. Three different structures of Si 5 H 10 with different symmetries are analyzed, and the results show that the envelope (C s ) and the twist (C 2 ) forms have similar energies and that the planar form (D 5 h ) is about 50 meV less stable than the C s and C 2 forms. The ring-open reaction of Si 5 H 10 is investigated in detail by using the first-principles molecular-dynamics simulation for screening the reaction pathways. The formation of Si–H–Si is found to play an important role in the ring-open reaction.

Indium-doped ZnO nanometre thick disks were successfully fabricated by thermal evaporation of a powder mixture of ZnO, In2O3, and graphite without catalyst. Incorporation of indium metal in the nanodisks during the synthesis was not successful due to the formation of In2O3 phase. SEM images show that some ZnO disks have perfect hexagonal shape. These disks are about 1–5 µm in size and 40–100 nm in thickness. X-ray diffraction, Raman, transmission electron microscopy, and energy dispersive spectroscopy observations show that the disks are single crystalline ZnO with wurtzite structure. Effect of indium doping on the structure, morphology, optical absorption, and photoluminescence of the nanodisks are studied.

A first-principles electronic structure calculation is performed to explore stability and electronic structure of Pt 13 cluster adsorbed on carbon supports. The stability of Pt 13 cluster on carbon nanotube supports has enhanced significantly, compared with that on graphene support. Charge re-distribution among Pt atoms takes place. Electronic structure of carbon supported-Pt cluster exhibits metallic characteristics, similar to a Pt metal surface.

We present our studies of electronic structure and magnetic properties of Mn 4 + Mn 3 3 + single-molecule magnets (SMM), i.e, [ Mn 4 + Mn 3 3 + O 3 Cl 4 ( OAc ) 3 ( py ) 3 ] (py = pyridine) and [ Mn 4 + Mn 3 3 + O 3 Cl ( OAc ) 3 ( dbm ) 3 ] (dbmH = dibenzoyl-methane) molecules by using a first-principles all-electron relativistic method within spin-polarized density functional theory. To investigate the possibility of ligands controlling the electronic structure and magnetic properties, we designed and calculated the geometric and electronic structures of twelve other Mn 4 + Mn 3 n + (n = 2, 3, 4) molecules with different peripheral-ligand configurations. The electronic structure of Mnn+ ions, and the interatomic distances, electronic structure and magnetic properties of Mn 4 + Mn 3 n + molecules display an interesting variation with n.

A novel fulleride Sm6C60 has been synthesized using high temperature solid state reaction. The Rietveld refinement on high resolution synchrotron X-ray powder diffraction data shows that Sm6C60 is isostructural with body-centered cubic A6C60 (A=K, Ba). Raman spectrum of Sm6C60 is similar to that of Ba6C60, and the frequencies of two Ag modes in Sm6C60 are nearly the same as that of Ba6C60, suggesting that Sm is divalent and hybridization between C60 molecules and the Sm atom could exist in Sm6C60. Resistivity measurement shows a weak T-linear behavior above 180 K, the transport at low temperature is mainly dominated by granular-metal theory.

In this paper we first present a new fabrication process of downscaled graphene nanodevices based on direct milling of graphene using an atomic-size helium ion beam. We address the issue of contamination caused by the electron-beam lithography process to pattern the contact metals prior to the ultrafine milling process in the helium ion microscope (HIM). We then present our recent experimental study of the effects of the helium ion exposure on the carrier transport properties. By varying the time of helium ion bombardment onto a bilayer graphene nanoribbon transistor, the change in the transfer characteristics is investigated along with underlying carrier scattering mechanisms. Finally we study the effects of various single defects introduced into extremely-scaled armchair graphene nanoribbons on the carrier transport properties using ab initio simulation.

In situ high pressure x-ray diffraction experiments revealed that a transformation from the two-dimensional (2D) tetragonal ${\mathrm{C}}_{60}$ polymer to a three-dimensional (3D) polymer takes place via a highly anisotropic deformation of ${\mathrm{C}}_{60}$ molecules along the c axis, as an irreversible first-order transformation above 20 GPa. In the 3D polymer phase, the $2+2$ bonds remain in the 2D plane, while neighboring layers are connected by the $3+3$ bonds. The bulk modulus of the 3D polymer was 407 GPa, being slightly smaller than that of diamond.

Supervisor:三谷 忠興, 材料科学研究科, 博士

We report that the ternary ${\mathrm{MgB}}_{2\ensuremath{-}x}{\mathrm{C}}_{x}$ compounds adopt an isostructural ${\mathrm{AlB}}_{2}$-type hexagonal structure in a relatively small range of nominal carbon concentration, $xl0.1.$ The lattice parameter a decreases almost linearly with increasing carbon content x, while the c parameter remains unchanged, indicating that carbon is exclusively substituted in the boron honeycomb layer without affecting the interlayer interactions. The superconducting transition temperature ${T}_{c}$ decreases quasilinearly as a function of the carbon concentration, with a slope steeper than that for the isoelectronic ${\mathrm{Mg}}_{1\ensuremath{-}x}{\mathrm{Al}}_{x}{\mathrm{B}}_{2}.$