Structural change of water with solutes and temperature up to 100 degrees C in aqueous solutions as revealed by attenuated total reflectance infrared spectroscopy

The attenuated total reflectance infrared (ATR-IR) spectra of several aqueous solutions have been measured by using a newly developed heatable rod-type ATR cell. The OH stretching bands showed systematic change with increasing solute concentrations and these changes can be explained by four different OH components based on curve-fitting results. NaCl solutions show longer H-bond distance character, while carbonate solutions present shorter ones. The Na2CO3 1 M solution conserves this shorter H-bond nature up to 100 degrees C. On the other hand, the loose nature of NaCl solutions becomes less pronounced at higher temperatures because of the dissociation of pure water clusters. These in situ observations of water structures are generally in agreement with the expected nature of fluids within the earth.     

Preparation of carbon microparticle assemblies from phenolic resin using an inverse opal templating method

Three-dimensionally (3D) well-ordered carbon microparticle assemblies with different particle morphologies were fabricated by infiltration of phenolic resin solution into SiO₂ inverse opal structures and subsequent carbonization. The effect of the phenolic resin solution concentration and the carbonization temperature on the morphology of the fabricated carbon microparticles was investigated. At a carbonization temperature of 1000 °C, carbon microparticles with interlocked bridges were obtained when the concentration of phenolic resin solution is 40 wt% and hollow carbon microparticles with opened window channels were obtained at a concentration of 30–35 wt%. When the carbonization temperature was decreased to 500 °C, carbon microparticles with interlocked bridges also were observed, even when the phenolic resin concentration was 30 wt%. The structures and properties of the carbon microparticles and their assemblies were characterized using SEM, XRD, and N₂ adsorption.     

Color displays and flexible displays using quick‐response liquid‐powder technology for electronic paper

Abstract— Color displays and flexible displays that use electronic liquid powder have been developed. Novel types of color displays using either a colored powder or a color filter are discussed. We have also developed a flexible display with low‐cost substrate films with a high‐throughput roll‐to‐roll manufacturing method. These technologies enable a QR‐LPD to be widely used as an electronic‐paper display.     

Characterisation of optically driven microstructures for manipulating single DNA molecules under a fluorescence microscope

Optical tweezers are powerful tools for manipulating single DNA molecules using fluorescence microscopy, particularly in nanotechnology‐based DNA analysis. We previously proposed a manipulation technique using microstructures driven by optical tweezers that allows the handling of single giant DNA molecules of millimetre length that cannot be manipulated by conventional techniques. To further develop this technique, the authors characterised the microstructures quantitatively from the view point of fabrication and efficiency of DNA manipulation under a fluorescence microscope. The success rate and precision of the fabrications were evaluated. The results indicate that the microstructures are obtained in an aqueous solution with a precision ∼50 nm at concentrations in the order of 10⁶ particles/ml. The visibility of these microstructures under a fluorescence microscope was also characterised, along with the elucidation of the fabrication parameters needed to fine tune visibility. Manipulating yeast chromosomal DNA molecules with the microstructures illustrated the relationship between the efficiency of manipulation and the geometrical shape of the microstructure. This report provides the guidelines for designing microstructures used in single DNA molecule analysis based on on‐site DNA manipulation, and is expected to broaden the applications of this technique in the future.Inspec keywords: DNA, molecular biophysics, fluorescence, optical microscopy, radiation pressure, biological techniquesOther keywords: optically driven microstructures, single DNA molecule analysis, fluorescence microscopy, optical tweezers, nanotechnology‐based DNA analysis, manipulation technique, aqueous solution, fine tune visibility, yeast chromosomal DNA molecules, geometrical shape, on‐site DNA manipulation     

Fatigue threshold and low-rate crack propagation properties for structural steels in 3 Pct sodium chloride aqueous solution

The fatigue threshold and low-rate crack propagation properties for a carbon steel, two high-strength steels, and two stainless steels were investigated in a 3 pct sodium chloride aqueous solution at frequencies between 0.03 and 30 Hz. Tests were conducted in a manner designed to avoid crack closure. Under freely corroding conditions, the effective values of the threshold stress intensity factor range, ΔK_th,eff, were lower than in air for all of the steels. In particular, the ΔK_th,eff values for the carbon and high-strength steels were almost equal to the theoretical ΔKth value of about 1 MPa m^1/2 calculated on the basis of the dislocation emission from the crack tip. At a given ΔK level higher than the threshold, the fatigue crack propagation rates accelerated with decreasing frequency for all of the steels. Under cathodic protection, the threshold and fatigue crack propagation properties were coincident with those in air regardless of material and frequency. The observed fatigue crack propagation behavior in a 3 pct NaCl solution was closely related to the corrosion reaction of the bare surface formed at the crack tip during each loading cycle.     

Numerical simulation of GaN single-crystal growth process in ammonothermal autoclave – Effects of baffle shape

The numerical simulation of an ammonothermal process for growing GaN bulk single crystals has been performed by using the SC/Tetra computational fluid dynamics software. The autoclave is assumed to be axisymmetric. Heat transfer by natural convection is discussed in the case of flat and funnel-shaped baffles. Simulation results show that the optimum baffle angle is approximately 20°. This result is identical to that obtained in our previous study on the hydrothermal ZnO crystal growth process.     

Micropatterning of liquid crystalline polyacetylene derivative by using self-organization processes

Side-chain type liquid crystalline polyacetylene, which has mesogenic moieties as side chains, is one of the promising materials for practical applications in the electronics. Micropatterning of the conductive polymer is a significant issue in this field. We show a simple method to fabricate micropatterns of side-chain type liquid crystalline polyacetylene derivative. Under dry condition, stripes patterns and lattice pattern were formed based on the fingering instability and stick-slip motion of the receding meniscus. Honeycomb-patterned polymer film was obtained by casting polymer solution under humid condition. The micropatterns drastically changed by changing solution concentration and preparation conditions.     

Synthesis and Characterization of Tetravalent Cerium Complexes with p-Tert-butylcalix[ n ] arenes （ n = 4, 6, 8）

Ａｓａｂｒａｎｃｈｏｆｓｕｐｅｒａｍｏｌｅｃｕｌａｒｃｈｅｍ ｉｓｔｒｙ ,ｌａｎｔｈａｎｉｄｅｃａｌｉｘａｒｅｎｅｃｈｅｍｉｓｔｒｙｈａｓａｔ ｔｒａｃｔｅｄｃｏｎｓｉｄｅｒａｂｌｅｒｅｓｅａｒｃｈｉｎｔｅｒｅｓｔｆｏｒｓｅｖｅｒ ａｌｙｅａｒｓ[1～ 5 ] .Ｉｎｔｈｉｓｒｅｓｐｅｃｔ,Ｈａｒｒｏｗｆｉｅｌｄｅｔａｌ.[6～ 13] ｓｙｎｔｈｅｓｉｚｅｄａｌｏｔｏｆｌａｎｔｈａｎｉｄｅｃａｌ ｉｘａｒｅｎｅｃｏｍｐｌｅｘｅｓ ,ａｎｄｒｅｖｅａｌｅｄｔｈｅｉｒｃｒｙｓｔａｌｓｔｒｕｃｔｕｒｅｓ .Ａｍｏｎｇｓｔｔ…     

Susceptibility of nude mice carrying the Fv-4 gene to Friend murine leukemia virus infection

Fv-4 is a mouse gene that dominantly confers resistance to infection with Friend murine leukemia virus (F-MuLV) (S. Suzuki, Jpn. J. Exp. Med. 45:473-478, 1975). Despite complete resistance to ecotropic MuLV infection in mice carrying the Fv-4 gene, it is known that cells carrying the resistance gene in tissue culture do not always show resistance as extensive as that in vivo (H. Yoshikura and T. Odaka, JNCI 61:461-463, 1978). To investigate the immunological effect on resistance in vivo, we introduced the Fv-4 gene into BALB/c nude mice (Fv-4-/- nude[nu/nu]) by mating them with Fv-4 congenic BALB/c mice (Fv-4r/r nude+/+) and examined the susceptibility of the F2 progeny to F-MuLV. All BALB/c nude mice without the Fv-4 gene (Fv-4-/- nude[nu/nu]) were permissive to F-MuLV and developed erythroleukemia within 2 weeks after virus inoculation. The BALB/c nude mice with the Fv-4 gene (Fv-4r/r nude[nu/nu]) did not develop leukemia, and no or little virus was detected in the spleen 7 weeks after virus inoculation. The resistance to F-MuLV was dominant in (Fv-4 congenic BALB/c x BALB/c nude) F1 mice with the Fv-4r/- nude(nu/+) genotype as strictly as in (Fv-4 congenic BALB/c x BALB/c) F1 mice with the Fv-4r/- nude+/+ genotype. However, almost all BALB/c nude mice with the Fv-4r/- nude(nu/nu) genotype developed the disease within 7 weeks, and the virus was detected in all of their spleens even in the mice without leukemia. These results show that the resistance caused by the Fv-4 gene is recessive in nude mice and dominant in BALB/c mice. Some immunological effects, perhaps cell-mediated immunity, may play important roles in the resistance to F-MuLV infection in vivo in addition to the dosage effect of the Fv-4 product.