Characterization of carbonaceous films deposited on metal substrates by liquid-phase electrodeposition in methanol

In this study, we report the characterization of carbonaceous films deposited on metal substrates by liquid-phase electrodeposition in methanol. The characterization of carbonaceous films by electrodeposition was examined by means of Raman spectroscopy, X-ray photoelectron spectroscopy (XPS), electron energy loss spectroscopy (EELS), secondary ion mass spectrometry (SIMS), atom probe (AP) and high resolution-elastic recoil detection analysis (HR-ERDA). From these results, it was found that the films deposited on the metal substrates were composed of the sp² and sp³ carbon contents, of which the ratio was about 7:3. Furthermore, the films by electrodeposition contained much hydrogen. The hydrogen contents in the surface were about 60 at.% and those in the subsurface were a few 10 at.%.     

Covalently cross-linked multilayer thin films composed of diazoresin and brilliant yellow for an optical pH sensor

The multilayered thin films composed diazoresin (DR) and brilliant yellow (BY) were fabricated by a layer-by-layer (LbL) deposition technique, and the ionic bonds between diazonium ion in DR and sulfonate residues in BY were converted to covalent bonds by UV light irradiation. The cross-linking between BY and DR prevented BY from desorption even in a pH 13 solution. The cross-linked (DR/BY)₁₀DR film exhibited pH-dependent absorption spectra in pH 9-13, and the response was repeatable and quick. The pH response time of the films was within a few seconds upon change from pH 9.0 to 13.0, and ca. 40 s upon change from pH 13.0 to 9.0.     

Nanosized‐Layered LiVO2 Prepared from Peroxo‐Polyvanadic Acid and Its Electrochemical Properties

Nanosized‐layered rock‐salt LiVO₂ was prepared by a new method from peroxo‐polyvanadic acid. The X‐ray diffraction pattern was well fitted with the space group R?3m in the Rietveld analysis and the crystallite size was estimated at 47 nm. The electrochemical properties as cathode materials for lithium ion batteries were investigated. The specific capacity of LiVO₂ was greatly improved to 149 mAh/g under the current density of 149 mA/g, in comparison with that of the conventional LiVO₂ below 50 mAh/g prepared by the solid‐state reactions.     

浅谈新农村居住小区建设项目施工阶段的造价控制

随着农民收入的增加,农民对居住条件的改善要求更加强烈,而对于自身住房的造价则尤为关注。对于新农村居住小区的建设而言,施工阶段合理的控制造价有着重要的意义。     

Effect of collagen fibril formation on bioresorbability of hydroxyapatite/collagen composites

Porous hydroxyapatite/collagen (HAp/Col) composite is a promising biomaterial and a scaffold for bone tissue engineering. The effect of fibril formation of Col in the porous composite on bioresorbability and mechanical strength was investigated. The fibril formation, in mixing a self-organized HAp/Col nanocomposite and sodium phosphate buffer at a neutral condition, occurred during incubation at 37 °C, resulting in gelation of the mixture. The porous composites with and without the incubation were obtained by freeze-drying technique, in which macroscopic open pores were formed. The compressive strength of the porous composite with the incubation (34.1 ± 1.6 kPa) was significantly higher than that without the incubation (28.0 ± 3.3 kPa) due to the fibril formation of Col. The implantations of the porous composites treated with a dehydrothermal treatment in bone holes revealed that bioresorption was clearly depended on the fibril formation. The bioresorbability in vivo was almost matched to the in vitro test using enzymatic reaction of collagenase.     

Fabrication of silica/platinum core-shell particles by electroless metal plating

An electroless metal plating method was used to form Pt shells on sub-micrometer-sized silica (SiO₂) particles fabricated by a sol-gel method. The electroless metal plating method was comprised of three steps: (1) surface-modification of SiO₂ particles with polyvinylpyrrolidone (PVP) (SiO₂/PVP) or poly-diallyldimethylammonium chloride (PDADMAC) (SiO₂/PDADMAC), (2) pre-deposition of Pt nuclei or Pt fine particles on the SiO₂ particles by reducing Pt ions in the presence of SiO₂/PVP particles (SiO₂/PVP-Pt) or SiO₂/PDADMAC particles (SiO₂/PDADMAC-Pt), and (3) growth of the pre-deposited Pt by immersing the SiO₂/PVP-Pt or SiO₂/PDADMAC-Pt particles in a Pt-plating solution. The pre-deposition of Pt nanoparticles was successfully performed for the surface-modified SiO₂ particles since the surface modification possibly strengthened the affinity between the SiO₂ particle surfaces and Pt ions. The Pt nanoparticles were pre-deposited more uniformly in the case of PVP because the pre-deposition took place more slowly for the PVP, which provided uniform surface-modification followed by the uniform pre-deposition of Pt nanoparticles. The formation of Pt shells was successfully performed on the SiO₂/PVP-Pt particles in the electroless metal plating process because Pt nuclei were generated by the reduction of H₂PtCl₆ and then further deposited on the Pt particle surfaces on the SiO₂/PVP-Pt particles.     

Four-point probe resistance measurements using PtIr-coated carbon nanotube tips

We performed four-terminal conductivity measurements on a CoSi2 nanowire (NW) at room temperature by using PtIr-coated carbon nanotube (CNT) tips in a four-tip scanning tunneling microscope. The physical stability and high aspect ratio of the CNT tips made it possible to reduce the probe spacing down to ca. 30 nm. The probe-spacing dependence of resistance showed diffusive transport even at 30 nm and no current leakage to the Si substrate.     

Detection method of emerging leading papers using time transition

To survive worldwide competitions of research and development in the current rapid increase of information, decision-makers and researchers need to be supported to find promising research fields and papers. But finding those fields from an available data in too much heavy flood of information becomes difficult. We aim to develop a methodology supporting to find emerging leading papers with a bibliometric approach. The analyses in this work are about four academic domains using our time transition analysis. In the time transition analysis, after citation networks are constructed, centralities of each paper are calculated and their changes are tracked. Then, the centralities are plotted, and the features of the leading papers are extracted. Based on the features, we proposed ways to detect the leading papers by focusing on in-degree centrality and its transition. This work will contribute to finding the leading paper, and it is useful for decision-makers and researchers to decide the worthy research topic to invest their resources.