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Open innovation (OI) is a crucial strategy regardless of sector, public or private, or academic or practical. However, the concept itself is often considered abstract and broad. Therefore, this study explored the coauthorship network and its groups to empirically observe the phenomenon of an open innovation. It also examined the semantic network of subject fields in open innovation research. We used coauthorship data to observe collaboration among authors. To examine how an open innovation is conceptualised and explained in academia, we used the abstracts of papers and the classification data of the journals where the papers were published. The results of the analysis found a mainstream group, which is a small group-to-group connection. We observed that the small groups are connected by key authors. We found that a social network of authorship and a semantic network of abstracts are both closely related. Our results provide a deeper understanding of an open innovation.

We report the oxygen evolution reaction (OER) catalyst composed of cobalt–calcium phosphate on reduced graphene oxide (CoCaP/rGO). Our catalyst is prepared by the anodic electrolysis of calcium phosphate/rGO mixture loaded on indium-tin-oxide (ITO) in Co2+ aqueous solution. TEM, XPS and XRD experiments confirm that the crystal phase of calcium phosphate (CaP) is transferred into an amorphous phase of calcium oxide with phosphate (5.06 at%) after anodic electrolysis. Additionally, the main cation component of calcium is replaced by cobalt ion. The current–voltage characteristics of CoCaP/rGO showed a shoulder peak at 1.10 V vs. NHE, which originated from Co2+ to higher oxidation states (Co3+ or Co4+) and a strong wave from water oxidation higher +1.16 V vs. NHE at neutral condition (pH 7). CoCaP and CoCaP/rGO showed 4.8 and 10 mA/cm2 at 0.47 V of overpotential, respectively. The enhanced OER catalytic activity of CoCaP/rGO arises from the synergetic interaction between the amorphous phase of CoCaP and electric conducting graphene sheets.

Amorphous cobalt–calcium phosphate composite (CCPC) films are electrochemically prepared on various electrodes by utilizing the solid phase of hydroxyapatite as a phosphate source. The CCPC film formation is surface process in which the dissolution of hydroxyapatite and the deposition of CCPC film concurrently occur on the electrode surface without the mass transfer of phosphate ions into the bulk solution. Elemental, crystallographic, and morphological analyses (EDX, ICP-AES, XPS, and XRD) indicate that the CCPC is composed of amorphous cobalt oxide with calcium and phosphate. The film exhibits durable oxygen evolution reaction (OER) catalytic properties under neutral and basic aqueous condition. Compared to using solution phase of phosphate source, our preparation method utilizing solid hydroxyapatite has advantage of preventing unnecessary chemical reaction between phosphate and other chemical species in bulk solution.

The hardnesses of carbon-doped TiMeN (Me = Zr, Al, and Cr) coatings were investigated in terms of lattice distortion and residual stress according to the difference in the ionic radii of the transition metal. TiMeN coatings were deposited on SUS304 by sputtering, and laser carburization was carried out for carbon doping. The scratch test showed that the delaminations of TiZrN, TiAlN, and TiCrN coatings were occurred about 13 N, 19 N, and, 16 N before and after carbon doping. The rate of hardness increase rate of TiZrN with carbon doping was the highest at 15.1%, and that of TiAlN and TiCrN were at 8.8% and 10.7%, respectively. The difference in hardness was analyzed by Rietveld refinement using HR-XRD, and the change in the lattice constant for TiZrN was 0.18 A, which was larger than that of TiAlN (0.10 A) and TiCrN (0.07 A). The expansion distortion was confirmed by the increase in lattice constant, and the doped carbon affected the lattice distortion differently depending on the ionic radius of the transition metal. The variation in residual stress through the lattice distortion was identified by the sin2Ψ method using HR-XRD with parallel beam and tilting of the specimen. The TiZrN coating showed the largest residual stress variation at 22%, and TiAlN and TiCrN showed similar tendencies at 11% and 13%, respectively.

In this study, a surface failure analysis was performed on an aluminum chromium nitride (AlCrN) coating formed on a tungsten carbide (WC) substrate used in a glass-molding machine and subjected to oxidation at elevated temperatures. Several pinholes were observed in the coating, with the coating surface exhibiting discoloring. The microstructures, crystalline structures, and elemental compositions of the coating and substrate were observed using scanning electron microscopy, X-ray diffraction analysis, and X-ray fluorescence spectroscopy. In particular, the phenomena occurring near the coating/substrate interface were examined using focused ion beam milling and grazing incidence X-ray diffraction analysis. The pinholes-containing coating area consisted of an oxide, with the composition of the coating being inhomogeneous. Further, voids were present near the substrate/coating interface, with some of the coating components being detected in the substrate as well. It was concluded that the Al/Cr atomic ratio of the AlCrN coating was not constant, owing to the oxidation of the coating at the elevated temperatures.

Failure analysis was performed on WC–Co hard metal molds after long-term use in a bottle cap forming machine. In addition, we simulated the optimal physical properties of the top and bottom molds for minimizing the wear caused by long-term use. To this end, we investigated the microstructure, wear, hardness, and transverse rupture strength (TRS) of the top and bottom molds with different WC particle sizes and WC/Co content ratios via simulations with Poisson's ratio and Young's modulus as inputs. The results show that a large stress distribution at the top and bottom molds did not signify a high maximum stress value; the stress distributions and maximum stress depended on the combination of materials used for the molds. It was concluded that WC–Co hard metal molds with similar physical properties would fracture readily or suffer wear due to the relatively high stress, where the optimal combination showed the lowest maximum stress (compared with the other combinations) at the top mold, with a larger stress distribution than that of the bottom mold. These findings are expected to be useful for optimizing applications where hard metal pieces come into contact, e.g. designing molds for bottle cap forming machines with longer lifetimes and fewer bottle cap defects.

This paper details the failure analysis of swelling in prismatic lithium-ion batteries (LIBs) after undergoing several charge–recharge cycles subsequent to long-term storage. The methods of analysis are nondestructive and mainly involve the use of computed tomography (CT) and cell disassembly. Two situations are compared. The first cell is examined after long-term storage, in which case a void space, presumably a gas bubble, is observed around the Ni tap in the cell, and traces of side reactants are found around the center of the anode electrode. This cell is compared with a swollen cell examined after undergoing several cycles after long-term storage, in which, according to the CT results before and after gas removal, gas is detected inside the jelly roll and inside the space between the can body and the jelly roll. Moreover, side reactants are identified near the center of the anode electrode, causing the color of the anode electrode to become irregular. The results show the gas bubbles and side reactants generated as a result of long-term storage are determined to be responsible for the swelling in the cell due to prolonged cycling.

The purpose of this study was to determine whether a support vector machine (SVM) model based on quantitative susceptibility mapping (QSM) can be used to differentiate iron accumulation in the deep grey matter of early Parkinson&rsquo, s disease (PD) patients from healthy controls (HC) and Non-Motor Symptoms Scale (NMSS) scores in early PD patients. QSM values on magnetic resonance imaging (MRI) were obtained for 24 early PD patients and 27 age-matched HCs. The mean QSM values in deep grey matter areas were used to construct SVM and logistic regression (LR) models to differentiate between early PD patients and HCs. Additional SVM and LR models were constructed to differentiate between low and high NMSS scores groups. A paired t-test was used to assess the classification results. For the differentiation between early PD patients and HCs, SVM had an accuracy of 0.79 &plusmn, 0.07, and LR had an accuracy of 0.73 &plusmn, 0.03 (p = 0.027). SVM for NMSS classification had a fairly high accuracy of 0.79 &plusmn, 0.03, while LR had 0.76 &plusmn, 0.04. An SVM model based on QSM offers competitive accuracy for screening early PD patients and evaluates non-motor symptoms, which may offer clinicians the ability to assess the progression of motor symptoms in the patient population.

A surface analysis was performed on an aluminum chromium nitride (AlCrN) coating formed on a tungsten carbide (WC) substrate subjected to short-term (in minutes) oxidation at an elevated temperature (900 °C) using focused ion beam (FIB), X-ray photoelectron spectroscopy (XPS), grazing incidence X-ray diffraction (GI-XRD), and laser-induced breakdown spectroscopy (LIBS). To separately analyze a coating with a thickness of several micrometers, the GI-XRD method was used. For cross-sectional imaging, the samples were milled using an FIB system, and chemical bonding states and surface elemental concentrations were analyzed by XPS. Within just a few seconds, the color of the AlCrN coating surface changed irregularly and, after 10 min, the entire coating layer surface changed. The entire coating surface oxidation as discoloration progressed in partial areas after 30 min. Based on the GI-XRD and XPS results, after 1 min, alumina and chromium oxides formed on the outermost surface, and after 10 min, Cr-W and Co-W oxide phases appeared, resulting from a reaction with WC near the interface. The atomic concentration of nitrogen in the AlCrN coating decreased after few seconds on the outermost surface and was almost eliminated after 10 min; oxygen showed the opposite trend. Finally, the FIB and LIBS results showed that voids formed within the coating layer and interface at high temperatures, and diffusion of Al and Cr in subsequent reactions was identified. This work demonstrates interesting results from various analyses that differ from previously reported AlCrN coating oxidation behaviors, and could provide a better understanding of long-term reactions for the surface oxidation of AlCrN coatings at high temperatures.

N-doped TiO x films on the glass substrate were prepared by radio-frequency (RF) magnetron reactive sputtering of Ti target in a mixed gas of argon and dry air. The effect of substrate roughness and working pressure on the physical properties and the photocatalytic properties of the N-doped TiO x films was investigated. The surface roughness of glass substrate has little influence on the film properties such as produced phases, lattice parameters, introduced nitrogen contents, and atomic bonding configurations, but significant influence on the surface roughness of film resulting in the variation of the photocatalytic ability. The working pressure has little influence on the produced phases and the atomic bonding configurations, but significant influence on the atomic concentration of the N-doped TiO x film, resulting in the large variation of optical, structural, and photocatalytic properties. It is suggested that the high photocatalysis of N-doped TiO x film requires a certain range of the N doping concentration which shows the interstitial complex N doping states in TiO 2 .

A modified solid electrolyte interface (SEI) on a graphite negative electrode with a fluoroethylene carbonate (FEC) additive was prepared by narrow-range cycling in a cell formation process. The SEI surface properties were investigated by extreme high-resolution scanning electron microscopy (XHR-SEM) under low acceleration voltage and X-ray photoelectron spectroscopy (XPS). A linkage structure of submicron-sized particles on the SEI film layer largely developed by narrow-range cycling in the formation process; these particles were mainly composed of the inorganic component (P F bonding states, LiPxOyFz) from the FEC. The application of narrow-range cycling with an FEC additive in the formation process improves the cycling performance and Coulombic efficiency of the cell. It is suggested that the SEI layer modified with FEC-derived SEI components on the graphite anode electrode by narrow-range cycling in the formation process, could improve the cell performance.

We investigate the formation and distribution of the solid electrolyte interface (SEI) layer on a graphite anode with two additives [vinylethylene carbonate (VEC) and vinylene carbonate (VC)] in a formation process using XPS, field emission AES, and extreme high-resolution SEM (XHR-SEM) techniques, and we studied what factors play an important role in determining the formation of the SEI layer. The VEC-derived SEI behaviors (morphology, thickness, compound, and balance over electrode position) on a graphite anode largely depend on the elevated temperature. The VC-derived SEI layer is mostly formed in the initial charging step, showing simple growth (formation) behavior. It is suggested that the properties of the additives are important for SEI bonding configurations at the nanoscale film surface, and to achieve the stable SEI layer, there appears to be an effective formation process for the additive properties. This research highlights the challenges of developing a stable SEI layer with additives in the formation process for electric vehicle batteries and would make a contribution to the understanding of how formation conditions affect an SEI layer with respect to additive properties. Copyright © 2014 John Wiley & Sons, Ltd.

A new method for observing the outermost surface morphology and the thickness of solid electrolyte interphase (SEI) are presented. Low acceleration voltage in extreme high resolution scanning electron microscopy (XHR-SEM) provides detailed information on the SEI surface morphology due to secondary electron contrast mechanism. Also, XHR-SEM under low acceleration voltage with low energy induced ion etching in x-ray photoelectron spectroscopy (XPS) studies provides valuable information on the SEI layer thickness. More detailed properties of the SEI layer were investigated by transmission electron microscopy (TEM).

Complex N (NO)-doped TiOx films on the glass substrate were prepared by radio-frequency (RF) magnetron reactive sputtering of Ti target in a mixed gas of argon and dry air with low oxygen concentrations. The surface doping states and energy band gap properties were studied by XPS and density-functional theory (DFT) applied to a 2 × 2 × 1 supercell of N-doped TiO2 with oxygen deficiency. Although all the films exhibit an anatase structure, the photocatalytic properties as well as other film properties (lattice parameters, grain sizes, introduced nitrogen contents, and optical properties) largely depend on the air flow ratios. The electronic bonding configurations at the nanoscale film surface are extremely important for photocatalysis, and there appears an optimal surface nitrogen amount incorporated in the anatase TiO2 lattice. Reduced Ti ions (and regions) at the nanoscale surface are proposed to play an important role by providing a local charge imbalance through the Schottky-barrier-like mechanism. Our DFT calculation shows the modified band calculation, especially for the film surface, involving both oxygen deficiency and N (NO) doping is important, due to the variation in the number and location of the impurity levels in the energy band gap. It is suggested that interstitial NOx (or substitutional NO) doping states with oxygen vacancy involving N–Ti–O or Ti–N–O bondings (linkages) are more effective on photocatalysis than the substitutional N doping states with oxygen vacancy. The seemingly desired impurity energy level(s) introduced in the electronic band gap does not necessarily improve photocatalysis, despite the desired optical properties observed, due to the active recombination sites newly produced and the complexity of the nanoscale surface science.

The N-doped TiOx films were prepared by radio-frequency (RF) magnetron reactive sputtering of Ti target in a mixed gas of Ar, O2 and N2. The effects of varying oxygen and nitrogen flow ratios on the physical properties and photocatalytic properties with defect formation energies using DFT calculations were investigated, and the photocatalytic ability was evaluated by decomposition of NO gas. The photocatalytic properties as well as other film properties such as lattice parameters, grain sizes, surface atomic contents, surface doping configurations, and optical properties strongly depend on the gas flow ratios. The N-doping configuration in TiO2 is significantly affected by the oxygen concentration in sputtering, based on the XPS and the defect formation energy results. Also, the visible light photocatalysis of N-doped TiOx film requires a certain range of oxygen and nitrogen concentrations in the sputtering process. The substitutional N-doped TiO2 has weak photocatalysis compared with the interstitial N (or NOx)-doped TiO2, suggesting that the interstitial N (NOx)-doping states with the oxygen deficiency are more effective for photocatalysis than the substitutional N-doping states with the oxygen deficiency, probably due to the variation in the number and location of the impurity levels (active recombination sites) in the energy band gap.

—A-0 0.063 0.70 0.013 0.049 A-1 0.086 0.72 0.018 0.069 A-2 0.125 0.75 0.026 0.099 A-3 0.136 0.76 0.029 0.109 A-4 0.150 0.76 0.032 0.119 A-5 0.163 0.77 0.034 0.128 A-6 0.175 0.78 0.037 0.138 A-7 0.188 0.78 0.039 0.148 A-8 0.200 0.80 0.042 0.158

Electrospinning is a process in which an electrified liquid jet is ejected by the interaction between the surface tension and the exerted electric force on the droplet surface. It is important to understand the effects of an electric field on the path of the ejected jet from the droplet to the opposite electrode in the electrospinning process. The effects of electric fields on the formation of nano-webs are presented in this paper. As the design of the electrodes varies, the ejected jets were deposit on the screen, exhibiting different or chareateristics. The design of the electric field is a significant parameter in the attempt to control nano-web formation.

The nucleation and crystallization kinetics of CaO-Al2O3-2SiO2 crystals in powdered anorthite glass with particle size

【$Bi_2Sr_2CaCu_2O_x$ (Bi-2212) and $Bi_2Sr_2Ca_2Cu_3O_y$ (Bi-2223) high-Tc superconductors(HTS) have been manufactured by plasma spraying, partial melt process(PMP) and annealing treatment(AT). A Bi-2212/2223 HTS coating layer was synthesized through the peritectic reaction between a 0212 oxide coating layer and 2001 oxide coating layer by the PMP-AT process. The 2212 HTS layer consists of whiskers grown in the diffusion direction. The Bi-2223 phase and secondary phase in the Bi-2212 layer were observed. The secondary phase was distributed uniformly over the whole layer. As annealing time goes on, the Bi-2212 phase decreases with mis-orientation and irregular shape, but the Bi-2223 phase increases because a new Bi-2223 phase is formed inside the pre-existing Bi-2212 crystals, and because of the nucleation of a Bi-2223 phase at the edge of Bi-2212 crystals by diffusion of Ca and Cu-O bilayers. In this study the spray coated layer showed superconducting transitions with an onset Tc of about both 115 K, and 50 K. There were two steps. Step 1 at 115 K is due to the diamagnetism of the Bi-2223 phase and step 2 at 50 K is due to the diamagnetism of the Bi-2212 phase.】