Elastoplastic formulation for friction with orthotropic anisotropy and rotational hardening

In various fields of engineering, it is important to clarify the frictional sliding behavior over a wide scale. In this study, we formulate an anisotropic friction model with the orthotropy and rotation of a sliding surface based on the elastoplastic theory. This model can also describe preliminary microscopic sliding and rate-dependent frictional response. Further, basic experimental results of anisotropic frictional sliding can be pertinently represented by the present model. We also employ this model with the finite element method and analyze typical frictional contact problems. We then demonstrate the effect of anisotropy parameters on the numerical results.     

Digital holographic PTV for complicated flow in a water by two cameras and refractive index-matching method

Optical Review - A basic heat transfer promoter such as packed beds of spheres is one of the technologies of the promotion of heat transfer using the turbulent mixture. We carried out 3-D...     

Total Synthesis and Functional Evaluation of Fourteen Derivatives of Lysocin E: Importance of Cationic,Hydrophobic, and Aromatic Moieties for Antibacterial Activity

Lysocin E ( 1 ) is a structurally complex 37‐membered depsipeptide comprising 12 amino‐acid residues with an N‐methylated amide and an ester linkage. Compound 1 binds to menaquinone (MK) in the bacterial membrane to exert its potent bactericidal activity. To decipher the biologically important functionalities within this unique antibiotic, we performed a comprehensive structure‐activity relationship (SAR) study by systematically changing the side‐chain structures of l ‐Thr‐1, d ‐Arg‐2, N‐Me‐d ‐Phe‐5, d ‐Arg‐7, l ‐Glu‐8, and d ‐Trp‐10. First, we achieved total synthesis of the 14 new side‐chain analogues of 1 by employing a solid‐phase strategy. We then evaluated the MK‐dependent liposomal disruption and antimicrobial activity against Staphylococcus aureus by 1 and its analogues. Correlating data between the liposome and bacteria experiments revealed that membrane lysis was mainly responsible for the antibacterial functions. Altering the cationic guanidine moiety of d ‐Arg‐2/7 to a neutral amide, and the C7‐acyl group of l ‐Thr‐1 to the C2 or C11 counterpart decreased the antimicrobial activities four‐ or eight‐fold. More drastically, chemical mutation of d ‐Trp‐10 to d ‐Ala‐10 totally abolished the bioactivities. These important findings led us to propose the biological roles of the side‐chain functionalities.     

Development and optimization of water treatment reactors using TiO2-modified polymer beads with a refractive index identical to that of water

Optical Review - Various water purification reactors were constructed using beads of TiO2-coated MEXFLON, which is a fluoropolymer exhibiting a refractive index identical to that of water. The...     

Thermal properties of AlN–Ce:YAG composite ceramic phosphor for laser lighting

Optical Review - The AlN–Ce:YAG composite ceramic is an effective phosphor for high-power laser illumination. The thermal properties of an AlN–Ce:YAG composite phosphor were studied to...     

Laser electron acceleration beyond 100 GeV

Nowadays there is great progress on laser-driven plasma-based accelerators by exploiting petawatt-class lasers, where for one aspect electron beams can be accelerated to multi-GeV energy in a centimeter-scale plasma due to laser wakefield acceleration mechanism. While to date, worldwide researches on laser-plasma accelerators are focused to create compact particle and radiation sources for applications in a wide range of sciences, including basic, medical and industrial sciences, there are great interests in applications for high energy physics and astrophysics that explore unprecedented high-energy frontier phenomena, for which laser plasma accelerator concepts provide us with promising tools. Here, our endeavors toward “extreme light” in the IZEST are envisaged for the next 30 years perspective and issues on laser plasma electron acceleration beyond 100 GeV and furthermore toward the TeV regime, aiming at high energy physics applications.