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In this study, we demonstrate the fabrication of hybrid plasmonic solar cells using gold nanoparticles (AuNPs). Two types of AuNPs, gold nanospheres (AuNSs) and gold nanorods (AuNRs), were incorpor...

In this study, the effect of periodic patterned micro/nanostructures on the active layers of thin-film organic photovoltaics (OPVs) was investigated to improve the device performance. The p...

Gas sensing by using the transmission surface plasmon resonance (T-SPR) technique was demonstrated. Polyacrylic acid (PAA)/5-nm-thick gold/40-nm-thick silver/polycarbonate grating substrate...

Enhancement of photoisomerization of Azobenzene dye Chicago Sky Blue 6B (CSB) was attempted using long-range surface plasmon resonance (LRSPR). The CSB film was prepared on a grating substr...

A quartz-crystal-microbalance (QCM) and surface-plasmon-resonance (SPR) hybrid sensor was prepared, and the sorptions of water and ethanol vapors to polyvinyl alcohol (PVA) films were observed in situ. The shift of the SPR wavelength depended on the PVA film thickness as well as the sorbed vapor. It was estimated to be due to the film swelling induced by the vapor sorption and the relationship between the film thickness and the penetration depth of evanescent wave.

Electropolymerization of carboxylated conducting polymer/carbon nanotubes (CNTs) composites thin films has been studied by in situ electrochemical-surface plasmon resonance (EC-SPR) spectroscopy. Two derivatives of benzothiophene, thianaphthene-2-carboxylic acid and benzothiophene-2-propionic acid, composited with CNTs were electropolymerized in an acetonitrile with the potential range between 0 and 1.2 V at scan rate of 20 mV/s. The obtained films were characterized by in situ EC-SPR spectroscopy, UV-vis absorption spectroscopy, and atomic force microscopy. It was found that CNTs can improve properties of polymer/CNT composites films. Moreover, the obtained thianaphthene-2-carboxylic acid film can be further used for construction of immunosensor for detection of human IgG.

Poly(2–aminobenzylamine)/single wall carbon nanotube (P2ABA/SWNTS) thin films were fabricated for the detection of UA by using electrochemical surface plasmon resonance spectroscopy (EC–SPR) technique. The suspension of 0.01% wt of carboxylated SWNTSs was assembled on the polymer film because of the electrostatic and van der Waals interactions between the ‒COOH and ‒NH2. The P2ABA/SWNTS thin film formation on gold electrode was studied by EC–SPR technique. In this work, uric acid was detected by EC–SPR in PBS buffer comparing with the interference response with ascorbic acid. EC–SPR uric acid sensor using P2ABA/SWNTS thin film can be applied for the detection of uric acid in urine.

The functionalized pyrrole copolymers were fabricated by electropolymerization of pyrrole (Py) and functionalized pyrrole monomers, pyrrole-3-carboxylic acid (P3C) and 4-(3-pyrrole) butyric acid (PBA). The electrochemical behavior and doping/dedoping properties of the obtained copolymer thin films were investigated by cyclic voltammetry (CV) in neutral phosphate-buffered saline (PBS) solution. Moreover, the functionalized pyrrole copolymer films were characterized by UV-vis absorption spectroscopy and atomic force microscopy (AFM). The obtained copolymer thin films showed good stability and electroactivity in neutral PBS solution. The presented functionalized pyrrole copolymer thin films may possess potential applications to study in various systems of the biosensors.

In this study, we report on evaluation of liquid crystal (LC) cells using simultaneous surface plasmon resonance (SPR) and optical waveguide spectroscopy (OWS) technique in attenuated total reflection configuration. This technique allows for in-situ monitoring of alignment property of LC molecules adjacent to the surface and the bulk in the LC cell simultaneously. An increase of the hysteresis both for near the surface and whole cell was observed in SPR/OWS kinetic properties as the number of voltage cycling increased. The LC alignment properties after applying a DC voltage were also measured to study the effect of impurity residual ions in LC cells.

Organic field-effect transistors (OFETs) were fabricated using poly(3-hexyl thiophene) (P3HT), and the effects of inserted Lewis-acid thin layers on electrical properties were investigated. The OFETs have active layers of P3HT and vanadium pentoxide (V2O5) as a Lewis-acid layer. Larger drain currents were observed for the OFET with the V2O5 layer than that without the layer. The calculated field-effect mobility of the fabricated OFET was 1.4 × 10−2 cm2/(Vs), where as that of the OFET without the V2O5 layer was 6.2 × 10−3 cm2/(Vs). It was thought that charge transfer (CT) complex which was formed at the interface between P3HT and V2O5 layer was dissociated by gate voltage, and the generated holes seem to contribute to drain current and the apparent high mobility.

A new Mach-Zehnder type optical-interferometer utilizing evanescent wave illuminations of a reflected beam at a prism surface was constructed to evaluate photoreactive molecular thin films on a prism surface. Refractive index changes of the films due to photoisomerization of azo molecules on the prism caused by an irradiation beam were observed from phase changes between an incident beam and the reflected one at the prism surface. Real-time measurements were also demonstrated using the interferometer microscopy, exhibiting two dimensional distributions of the refractive indices in the molecular films partially excited by the focused irradiation laser beam.

Self-assembled layer-by-layer films were fabricated on Ag-evaporated glass substrates using Direct Red 80 (DR80) azobenzene dye and poly (diallyldimethylammonium chloride) (PDADMAC). The properties of attenuated total reflection (ATR) and emission due to surface plasmon excitation were investigated. The ATR was measured for the Kretschmann configuration of a prism/Ag/layer-by-layer film structure and the emission through the prism was measured when the sample was excited by reverse irradiation in the Kretschmann configuration. The peak angles of the emission spectra almost agreed with the resonant angles of the ATR curves. The shapes of the emission spectra also corresponded to the ATR curves. The structural change of the self-assembled films due to photoisomerization of DR80 molecules was also investigated. From the ATR measurements, the structure of the self-assembled films was found to change due to the photoisomerization by the irradiation of polarized visible light. The surface roughness of the self-assembled films due to the photoisomerization was examined from the scattered light measurements.

A liquid crystal (LC) cell with alternate self-assembled films containing azobenzene dye as aligning layers was fabricated and photo-induced inplane alignments of nematic LC molecules, 5CB, have been investigated in the cell using the attenuated total reflection (ATR) method. The ATR properties due to excitations of surface plasmon polaritons (SPP) were observed in the LC cell and sensitively changed with irradiation of linearly polarized visible light to the LC cell. The experimental results corresponded well with the calculated shifts at different alignment states. It was evaluated that the LC molecules within the penetration length of the SPP (about 130 nm) were aligned perpendicular to the polarized direction of the irradiation light, and that the tilt angle was almost 0 degree.

In this study, photocurrents enhanced by the surface plasmon polariton (SPP) excitation were observed in a merocyanine (MC) Langmuir-Blodgett (LB) film cell. The excitation of the SPP was carried out by the incidence of a laser beam in the attenuated total reflection (ATR) measurement system. The excitation of the SPP induces the strong absorption of the incident light and large photocurrents in the device.

Photo-induced in-plane alignments of nematic liquid crystal (LC) molecules. 5CB, have been investigated in the cell with alternate self-assembly films of polyelectrolyte and low-molecular weight dyes on the gold electrodes using the attenuated total reflection (ATR) measurement method. Reflectivities due to the excitations of the surface plasmon polariton (SPP) were observed in the ATR properties of the LC cell. In-plane switching of LC molecules adjacent to the aligning layer was evaluated from the ATR curves by means of irradiation of the linearly polarized visible light to the LC cell. It was also estimated that the re-orientation of the LC molecules occurred within about 130 nm from the surface of the aligning layer on the prism by the irradiation of the polarized light.

Tilt angles of liquid crystal molecules, 5CB, have been investigated in the liquid crystal cells with the polyimide (PI) LB alignment films on the aluminum electrodes using the attenuated total reflection (ATR) measurement. The ATR properties were evaluated from the surface plasmon polariton (SPP) and the guided wave excitation modes (GWEM) when various DC voltages were applied to the cell. The tilt angles of the liquid crystal molecules were calculated by fitting the theoretical ATR curves to the experimental ones using a three layers model. Furthermore, the electric field intensities in the cell were calculated at several incident angles.

The deposition ratio (Ba: Na: Nb) of tungsten-bronze type thin film ferroelectrics depend on the sputtering conditions. The dielectric constant, dielectric loss factor are 889 and 0.029 at room temperature. The leakage current density is about 100 μml A/cm2 at 1MV/cm. The remanent polarization and coercive field are 2.39 μml C/cm2 and 87.33kV/cm, and the SHG coefficient d is about 2.51 × 1013 m/V, respectively

The crystalline structure, dielectric relaxation and ferroelectric properties of the solid solution, Nd x Bi4-x Ti3O12 (NBIT) compound were measured. The Curie temperature of the NBIT ceramics was determined to be 490°C from dielectric measurements. The dielectric constant of the NBIT ceramics shows a small anisotropic property. Polarization switching was observed using a Sawyer-Tower circuit at 50 Hz. Remnant polarizations and coercive fields could not be confirmed since the hysteresis loops were not saturated. The large dielectric relaxation is observed in the frequency range between 100 kHz and 1 MHz.

Polycrystalline and epitaxial films of a layer-structured ferroelectric Bi4Ti3O12(BIT) in perovskite phase and tungsten-bronze typed Ba2NaNb5O15(BNN)have been deposited on sapphire and alumina substrates by ECR plasma and RF magnetron sputtering using a sintered ceramic target. The substrate temperature higher than 550°C was necessary to grow BIT films in the perovskite phase without post thermal annealing. BIT films were epitaxially grown on C.A and R surfaces of a sapphire single crystal. The deposition ratio of BNN film(Ba.Na.Nb) depended on the sputtering gas pressure. The dielectric, ferroelectric and optical properties of these films are discussed.

The present study was designed to clarify the role of calcium in suppressed renin release in DOCA-salt hypertension. Rat glomeruli were isolated by the modified Beierwaltes' sieving method. The glomeruli were superfused with Krebs-Ringer solution. Basal levels of renin release were lower in the DOCA-salt hypertensive rats (1.16 +/- 0.27 ng/ATI/hr/hr/10(4) glomeruli, mean +/- SEM, n = 8) than in the control rats (1.92 +/- 0.18, p less than 0.01, n = 8). Perfusion with a calcium free solution containing EGTA and A23187 stimulated renin release in the DOCA-salt hypertensive and control rats. The maximum levels of renin release during the perfusion in DOCA-salt hypertensive rats (1.79 +/- 0.17, n = 8) were lower than those in control rats (10.60 +/- 1.85, p less than 0.01, n = 8). These results suggest that high levels of intracellular calcium might not contribute to the suppression of renin release in DOCA-salt hypertension.

PURPOSE Information on the extent or structure of esophageal cancer (ESC) is necessary for identifying whether the carcinoma is localized or resectable. Diffusion-weighted imaging (DWI) and diffusion-weighted whole-body imaging with background body signal suppression (DWIBS) are useful for this purpose. PATIENTS AND METHODS One case of ESC with dysphagia presented at our hospital. Endoscopic examination revealed an elevated lesion with an ulcer, and stenosis was detected. DWI showed a high-intensity signal extending from the proximal to the distal ends of the carcinoma and extending to the tunica adventitia. A strong signal was also observed using (18)F-fluorodeoxyglucose positron emission tomography (FDG-PET). DWIBS clearly revealed ESC, and these findings, along with those from DWI, suggested that our case had stage-T3 ESC. FDG-PET did not reveal the detailed structure of the ESC. DWIBS, on the other hand, showed that the signal extended to the tunica adventitia and the lumen of the esophagus. CONCLUSION These findings suggest that DWI and DWIBS are useful for the detection and assessment of ESC.

The effects of physico‐chemical property (electronegativity) of the metals, temperature, light intensity (shading), metal concentration in the medium and the depth of the soil layers in which the metals were placed on the partitioning of the metals between roots and tops in rice plants have been investigated. The results can be summarized as follows: 1. Metals of large electronegativity were mainly accumulated in roots and only a small quantity of them was translocated to tops. 2. The increase in the metal concentration in the medium decreased the ratio of the translocation to tops. X‐ray micro‐analysis of the root revealed that the metal concentration around the stele was greatly increased when the metal was applied in high concentrations. 3. Shading and low temperature reduced the ratio of the translocation of the metals to tops. Cd and Zn were translocated as organo‐metal complexes in xylems. 4. Reduction of Eh of the soil by flooding decreased the metal translocation but not the uptake into r...

Tulip plants were planted in October and grown in culture solution in a glasshouse under natural conditions. One group of plants was cultivated in a medium containing nitrogen, while the other group in a nitrogen-free medium (—N treatment). Plants were first harvested in December, when the roots were developing actively. The total nitrogen content in the roots in the case of N treatment was very high (about 8.5%/dry weight), although that in the case of —N treatment was low (2.2%/dry weight). The absorbed nitrogen in the roots was accumulated mainly in the “80% ethanol soluble fraction” supplemented with the “water soluble but 80% ethanol insoluble fraction,” and glutamine was a major nitrogen constituent. On the other hand, γ-methyleneglutamine (γ-MGln) was a predominant amino acid in the roots in the case of —N treatment. Plants grown in the N medium were subsequently harvested at the flowering stage in April. At this stage the roots were absorbing nitrogen very actively and transporting it to the leave...

Some species of plants which belong to Asterales, Poales (Graminales), Liliales, Asparagas, and others contain fructan as a reserve carbohydrate (1). Three types of fructosylsucroses, isokestose (l-kestose, 1F-β-fructosylsucrose), kestose (6-kestose, 6F-β-fructosylsucrose), and neokestose (6G-β-fructosylsucrose) are key intermediates for the related highly polymerized oIigofructans (1, 2). Inulin is a higher homologous oligosaccharide of isokestose whose fructofuranosyl residues are (2-+1)-β-linked, and phlein (or levan) is a higher homologue based on the kestose whose fructosyl residues are joined by a (2→6)-β-linkage. Furthermore, there are also highly polymerized oligofructans related to neokestose. In the members of Liliales, all ,three types of fructans have been found (1). As for the tulip bulb, HAMMER investigated the trisaccharide from two species of tulips (Tulipa silvestris L. and Tulipa clusiana), and the results showed that the tulip bulb appeared to contain mainly isokestose together with tra...

Tulip plants accumulate a large quantity of N in their roots during the winter season. In order to analyze the role of root N accumulation on the growth and bulblet production, tulip plants were hydroponically cultured and a 15N feeding experiment was carried out. All the plants were fed with a 15N labeled culture solution for 1 month during winter, and two treatments were applied thereafter: one group of plants continued to grow in a standard culture solution containing N (+N treatment), and another was cultivated in N-free medium (-N treatment). At the time of planting one planting bulb on the average contained about 30 mg of stored N, and an additional amount of 20 mg labeled N was absorbed during the 15N feedings. On January 11 immediately after 15N feeding, 51% of total N was distributed in the roots, 30% in mother bulb scales, 15% in shoots, and 3% in the basal plate, respectively. At this stage, 15N labeled N was distributed as follows: roots 77%, mother bulb scales 11%, shoots 8%, and bas...

The changes in the carbohydrate and N constituents in tulip bulb scales were investigated in relation to the physiological role of cold treatment for forcing cultivation, by comparing the plants subjected or not subjected to the conventional cold storage treatment. When the bulbs subjected to cold storage were cultivated in a greenhouse, they grew rapidly and flowering occurred normally in early December, whereas without cold storage the growth of the shoots was markedly depressed, they exhibited a rosette form, and flowering occurred in the middle of January. Regarding the changes in the carbohydrate content in the scales of bulbs subjected to the cold treatment, starch degradation occurred rapidly after the onset of the treatment. Based on the morphological observations, small starch granules with a spherical shape disappeared initially, and subsequently the amount of the large granules with a lenticular shape decreased. Along with the starch degradation, there was a considerable accumulation o...

The paper describes the electric and magnetic properties of high Tc oxide superconductor, YBa2Cu3O7-δ ceramics, and influence of the sintering oxygen pressure conditions. All specimens showed the super-conductivity sintered at 950°C, a various sintering oxygen pressure from 24.5 to 147 kPa. The magnetization (M) T c-end and T c-onset are found the maximum value at 73.6 kPa oxygen pressure, respectively. On the other hand, lattice constant of c-axis considerably decreases against oxygen pressure and obtained a minimum value at 74 kPa. This corresponds to the maximum of Tc and M constant maximum. It seems that the optimum amount of oxygen was obtained at this oxygen pressure. The average copper charge (ACC) was estimated there, as 2.32, which corresponds to oxygen composition of 7-δ = 6.98. The apparent density of ceramics is about 5.6 × 103 kg/m3, which is about 90% of the theoretical one.

Electron microprobe analysis was applied to the localization of zinc, phosphorus, sulfur, and calcium within and around the rice root grown in the flooded soil of high zinc content (300 ppm). A method for the preparation of the section of the undisturbed soil with the rice root in place is described. Having been dehydrated with ethanol, the sample became free of water soluble ions and, therefore, the insoluble fractions of the elements were mainly localized. The results obtained were as follows: 1) A longitudinal view of the root in the soil was successfully shown as a secondary electron image. 2) The compaction effect of the expanding root on the orientation of the soil particles was not observed. 3) The distribution patterns of the elements in the apical region of the root differed distinctly from those in the basal region. In the latter region, the elements were accumulated in the cells of the epidermis, exodermis, endodermis, and marginal layers of stele. Zinc and phosphorus appeared to be in...

Fourteen untreated patients with essential hypertension (EH) were subjected to mild aerobic exercise with the intensity at 50% of the maximum oxygen uptake (VO2max) twice a week for 12 weeks, as compared with 14 normotensive subjects (NT). Blood pressure and norepinephrine (NE) in plasma, platelet and urine were measured as the indices of sympathetic activity. In EH, a significant fall in both systolic and diastolic blood pressure was observed. In addition, exercise training produced a significant decrease both urinary and platelet NE, but not in plasma NE. Neither significant changes in blood pressure nor NE in plasma, platelet and urine were observed in NT. These results suggest that an inhibition of the sympathetic nervous system might be related to the blood pressure fall in physical exercise training.