Terahertz Generation and Optical Properties of Lithium Ternary Chalcogenide Crystals

We have investigated the generation of THz radiation in lithium ternary compounds LiInSe₂, LiGaSe₂, LiInS₂, LiGaS₂ and characterized these materials by THz time-domain spectroscopy. Using 800 nm femtosecond excitation pulse, all crystals produce THz radiation due to an optical rectification corresponding to the nonlinear optical coefficient d ₃₃. We have measured refractive indices along the x-axis and the z-axis for all crystals in the range 150–700 μm and fitted them by using Sellmeier equation. With respect to the obtained results, velocity-matching between the incident laser pulse and the generated THz wave cannot be achieved at 800 nm, but for shorter wavelengths. Hence, an enhanced THz generation in Lithium ternary compounds may be observed by using a laser emitting below 800 nm.     

A finite element LES for high-Re flow in a short-elbow pipe with undisturbed inlet velocity

The paper is concerned with a large-eddy simulation (LES) for a high-Reynolds-number flow in a short-elbow pipe, which can potentially be employed in the primary piping system of the Japan Sodium-cooled Fast Reactor (JSFR). The basic performance of the LES is studied for an elbow pipe flow without turbulence at inlet boundary at Re = 1.2 × 10⁶ by comparison with a flow observed in a 1/3-scale water experiment, where the flow disturbance at the pipe inlet is small. In setting up the computational conditions, special care was taken to ensure that the mesh subdivision was suitable for the simulation of the pipe flow through a theoretical consideration. We discuss the effects of the turbulence model (Smagorinsky model, WALE model) and the inlet velocity profile on the results. The mechanism of the pressure fluctuation and the origin of the fluid force are also discussed with the aid of spectral analysis and the visualization of essential hydraulic quantities.     

Melt growth of multicrystalline SiGe with large compositional distribution for new solar cell applications

The melt-growth conditions to obtain SiGe multicrystals with microscopic compositional distribution are presented. These SiGe multicrystals are useful for new solar cells whose wavelength dependence of the absorption coefficient can be freely designed. The multicrystals with wide compositional distribution from Si to Ge can be grown by a melt growth technique such as the practical casting method. In this work, it was studied as to how much the micro- and macroscopic compositional distribution in SiGe multicrystals grown from binary Si–Ge melts could be controlled by the melt composition and the cooling process. Such SiGe multicrystals with wide distribution of the composition would also have wide distribution of the absorption coefficient, and could be hopeful for new solar cell applications using the practical casting method.     

A new non-contacting non-destructive testing method for defect detection in concrete

A new non-destructive testing (NDT) method for defect detection in concrete structures is presented. The method is based on the dynamic response of flawed concrete structures subjected to impact loading. Conversely to similar NDT techniques, such as the impact-echo method, the present method uses non-contacting devices for both impact generation (a shock tube producing shock waves) and response monitoring (laser vibrometers measuring concrete surface velocity). Experimental and numerical (finite element) studies have been carried out for concrete specimens containing artificial defects (penny-shaped cracks parallel to the free surface) with varying length and depth. According to the experimental and numerical results, it appears that the present method enables an effective detection of defects, particularly in the range of shallow defects.     

Integrated lipidomics in the secreted phospholipase a(2) biology

Mammalian genomes encode genes for more than 30 phospholipase A(2)s (PLA(2)s) or related enzymes, which are subdivided into several subgroups based on their structures, catalytic mechanisms, localizations and evolutionary relationships. More than one third of the PLA(2) enzymes belong to the secreted PLA(2) (sPLA(2)) family, which consists of low-molecular-weight, Ca(2+)-requiring extracellular enzymes, with a His-Asp catalytic dyad. Individual sPLA(2) isoforms exhibit unique tissue and cellular localizations and enzymatic properties, suggesting their distinct pathophysiological roles. Recent studies using transgenic and knockout mice for several sPLA(2) isoforms, in combination with lipidomics approaches, have revealed their distinct contributions to various biological events. Herein, we will describe several examples of sPLA(2)-mediated phospholipid metabolism in vivo, as revealed by integrated analysis of sPLA(2) transgenic/knockout mice and lipid mass spectrometry. Knowledge obtained from this approach greatly contributes to expanding our understanding of the sPLA(2) biology and pathophysiology.     

Fatigue behavior of plasma radical nitrided SCM435 steel in super-long life regime

Fatigue behavior in a super-long life regime was investigated for plasma radical nitrided JIS SCM435 steels at room temperature in air. Specimens were nitrided at the 723 K and 823 K for 3 h and at 773 K for 1 h, 3 h, and 5 h. The fatigue strengths of the nitrided specimens were greater than that of the un-nitrided specimen. However, the fatigue strength and fracture mechanism of the nitrided specimens were markedly influenced by nitriding temperature and time. Both surface cracking and subsurface cracking, e.g. fish-eye fractures, were observed in the specimens subjected to the nitriding conditions. Hardened layers and compressive residual stress were formed on the specimen surfaces by nitriding, which led to an improvement of the fatigue strength and determined the initiation type of the fatigue cracking. Stress intensity factor at crack initiation was evaluated in fish-eye type fractures. As a result, the stress intensity factor range in the facet area indicated a constant value, approximately 3.5 MPa·m^1/2, regardless of the fatigue life.     

Chemical modification of diamond surface with linoleic acid by using benzoyl peroxide

In this study, the introduction of the C=C bond, which is known to be chemically active, on diamond surface was attempted using a reaction with unsaturated fatty acid. The chemical reactivity of a hydrogenated diamond surface with linoleic acid, which was most effective for introducing of the C=C bond, using benzoyl peroxide was investigated in detail. The diamond surface modified with the C=C bond was used as the substrate for the surface-modified diamond. Different radical source such as NCS, NBS, AIBN, and TEMPO were allowed to react with the diamond surface treated with linoleic acid. After the reaction with NCS, NBS, or AIBN, IR peaks at 3011 cm^− 1, which correspond to the C-H bond on the C=C bond, significantly decreased in size, and XPS spectra showed that the elements that derived from the reacted radical source, that is Cl, Br, or N, existed on the diamond surface. On the other hand, after the reaction with TEMPO no XPS peak of the N atoms appeared although the IR peak at 3011 cm^− 1 slightly decreased. These experimental results indicate that the C=C bond introduced on diamond surface can participate in chemical reaction. The method used in this study could become a very useful technique if the coverage factor of the C=C bond is improved by optimization of the reaction condition.     

后工业社会环境中的人与住宅

过去半个多世纪中,生产和经济的快速发展,将人类社会逐渐从工业社会推进到了后工业社会,与社会文化紧密联系的住宅建设必然也会受到影响。以服务业为主的第三产业的崛起、信息技术的快速发展和个人意识的不断增强,使得住宅从设计建造到配套服务理念也在发生转变。从后工业社会的主要特点着手,列举中外典型住宅建造案例,分析在社会环境转化的过程中,人、住宅、建筑师以及其他部门之间的关系变化,并由此推测今后住宅建筑发展的可能趋势是：在工业化生产的基础上,住宅建设服务越来越重视个性和地域性的发展;住宅建造中的信息交流越来越频繁,各部门的角色相应调整;消费者或使用者更多地参与到住宅的设计建造过程中,并处于主要地位。     

Metallo-supramolecular Polymers: Versatile DNA Binding and Their Cytotoxicity

Metallo-supramolecular polymers (RuL1, RuL2, RuL3, FeL3, and FeL4) prepared by complexation of bis(terpyridine) derivatives with Ru²⁺ or Fe²⁺ ions with octahedral coordination structures showed high binding ability to several DNAs (calf thymus DNA, herring sperm DNA, [poly(dA-dT)]₂, and [poly(dG-dC)]₂), which were revealed by UV–Vis absorption titration experiments. The electrostatic interactions between the metal cations of the polymers and phosphate anions of DNA led to formation of conjugate structure. The binding constant observed reached 3.7 × 10⁷ M^?1, which is the highest among values reported for metal complexes to date. Based on a long strand structure of the polymer, groove binding is most possible binding mode. Cell viability experiments showed that RuL3 and FeL3 displayed highly statistical significance (**p<0.01) to human non small cell lung cancer cell lines (NCI-H460).     

Experimental study on load characteristics in a floating type pendulum wave energy converter

A floating type pendulum wave energy converter（FPWEC） with a rotary vane pump as the power take-off system was proposed by Watabe et al.in 1998.They showed that this device had high energy conversion efficiency.In the previous research,the authors conducted 2D wave tank tests in regular waves to evaluate the generating efficiency of FPWEC with a power take-off system composed of pulleys,belts and a generator.As a result,the influence of the electrical load on the generating efficiency was shown.Continuously,the load characteristics of FPWEC are pursued experimentally by using the servo motors to change the damping coefficient in this paper.In a later part of this paper,the motions of the model with the servo motors are compared with that of the case with the same power take-off system as the previous research.From the above experiment,it may be concluded that the maximum primary conversion efficiency is achieved as high as 98%at the optimal load.