Norifumi L. Yamada

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We propose a nondestructive or optical method of measuring the chlorophyll content in a leaf after constructing a mathematical model of reflectance and transmittance of plant leaves as a function of their chlorophyll pigment content. The model is based on the Kubelka-Munk theory and involves the modeling of the multiple reflection of light in a leaf that is(More)
Whereas the phase separation of normal phospholipids induces formation of microdomains on the surface of spherical vesicles, the separation of a long- and short-chain lipids can induce perforation of small unilamellar vesicles (SUVs) and transformation into bilayered micelles (bicelles) because the edges of the bilayers are stabilized by the short-chain(More)
Membrane fluctuations of dipalmitoylphosphatidylcholine (DPPC) and dimyristoylphosphatidylcholine (DMPC) were investigated by neutron spin echo spectroscopy. The intermediate structure factor was analyzed in terms of the model proposed by Zilman and Granek (Phys. Rev. Lett. 77, 4788 (1996)), and the bending modulus of lipid bilayers was derived. The(More)
The synergistic adsorption of a binary surfactant mixture was investigated by tensiometry and neutron reflectometry. The results directly contradicted the conventional Gibbs adsorption equation. The accompanied molecular simulation demonstrated a multilayer arrangement at the synergic conditions, with three distinctively oriented water layers. The positive(More)
We report the first operando measurement of solid electrolyte interphase (SEI) formation at an electrode using in situ neutron reflectometry. The results revealed the growth of the SEI and intercalation of ions during the charge reaction. Furthermore, we propose a way of evaluating the charge used for the SEI formation.
The motion of an oil-water interface that mimics biological motility was investigated in a Hele-Shaw-like cell where elastic surfactant aggregates were formed at the oil-water interface. With the interfacial motion, millimeter-scale pillar structures composed of the aggregates were formed. The pillars grew downward in the aqueous phase, and the separations(More)
The aggregation states of polystyrene (PS) thin films at interfaces with nonsolvents such as water, methanol, and hexane were examined by specular neutron reflectivity and sum-frequency generation vibrational spectroscopy. The density profiles of the PS thin films along the direction normal to the interface with water and methanol were comparable to that in(More)
In organic light emitting devices (OLEDs), interfacial structures between multilayers have large impacts on the characteristics of OLEDs. Herein, we succeeded in revealing the interdiffusion in solution processed and thermal annealed OLEDs by neutron reflectometry. We investigated interfaces between a polymer under layer and small molecules upper layer. The(More)
– Small-angle X-ray scattering and phase-contrast microscopy experiments were performed to investigate the effect of the osmotic pressure on vesicle formation in a dioleoylphosphatidylcholine (DOPC)/water/NaI system. Multi-lamellar vesicles were formed when a pure lipid film was hydrated with an aqueous solution of NaI. On the other hand, uni-lamellar(More)
The four tunneling times, the Larmor time, the Büttiker-Landauer time, the Bohm-Wigner time, and the Pollak-Miller time, originally obtained from very different physical models, are derived in a unified manner from the Gell-Mann-Hartle decoherence functionals. The origin of the two types of derivatives in the expressions for these tunneling times is(More)