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Inverse spinel oxide NiCo2O4 (NCO) is known to exhibit ferrimagnetic characteristics and electrical conductivity. First-principles calculations predict NCO to be a half-metal with a negative polarization of −100%. In this study, we fabricated epitaxial NCO/MgO/Fe magnetic tunnel junctions by reactive molecular beam epitaxy and observed an inverse tunnel magnetoresistance (TMR) effect of −19.1% at 14 K, indicating that NCO has negative spin polarization. The TMR ratio monotonically decreased with increasing temperature, which was attributed to the temperature dependence of the NCO surface magnetization due to the thermal excitation of spin waves. In addition, the TMR ratio displayed strong bias voltage dependence, decreasing to less than half of the maximum value at +20 and −30 mV. These findings support the use of NCO in spintronic devices and should lead to further developments in oxide spintronics. [ABSTRACT FROM AUTHOR]

The electro-optic response of the defect mode switching in the one-dimensional (1D) photonic crystals (PC) with the nematic liquid crystals (NLC) defect layer is analyzed by considering the molecular director distributions in the defect layer. The calculated defect mode switching has displayed a response in the order of microseconds, despite using the reorientation of NLC.

Three-dimensional periodic structures of synthetic opals and various inverse opals with interconnected regular array of nano-scale voids in which liquids and liquid crystals can be infiltrated have been prepared for the study of liquids and liquid crystals confined in nano-scale spaces. One-dimensional periodic structure containing a defect layer in which liquids and liquid crystals can be introduced have also been prepared by the multi-layered Si[O.sub.2] and Ti[O.sub.2] stacks. These three-dimensional and one-dimensional periodic structures containing liquids and liquid crystals exhibited novel properties as tunable photonic crystals. Utilizing these phenomena a simple apparatus to evaluate the refractive index of liquids precisely have been proposed, with which sorts of dielectric liquids can be distinguished. Kerr effect and non-linear optical effects of liquids contained in the defect layer of the one-dimensional systems have also been discussed. When the opals and inverse opals contain liquid crystals, the transmission dip and reflection peak wavelengths can be tuned by applied field. The response characteristics are different for opals and inverse opals, which can he interpreted by taking the interaction of liquid crystal molecules with the inner surface of the void into consideration. Utilizing one-dimensional systems containing liquid crystals in the defect layer a ultra-fast switching of a laser light and also in systems containing liquid crystals and fluorescent dyes a voltage tunable lasing in the wide spectral range have been demonstrated. Index Terms--Liquids, liquid crystals, periodic structures, carbon, electrooptic effects, nanostructures, photonic crystals.

Dielectric studies with characteristics of a photonic crystal and a new expression of Lamb Shift including spatial average of dielectric constant for the material and its surrounding for odd parity of [2p.sub.1/2] state of hydrogen for photon-atom interaction as a function of relative dispersion frequency, refractive index contrast and propagation vector using quadratic fluctuations and randomness in an anisotropic model of Brillouin Zone (BZ) for p-polarization are reported. The anomalous Lamb shift in [2p.sub.1/2] level is significantly more than that obtained by using isotropic model which indicates that introducing anisotropic behaviour of BZ is important. Index Terms--Photonic crystal, photonic band gap material, dielectric material, Lamb Shift, refractive index contrast.

New data of the electronic properties of liquid helium and liquid neon are discussed with respect to their relevance for the initiation of electric breakdown. It is concluded that under ideal conditions the cathode plays a decisive role in the initiation of the breakdown process. It is speculated that a Townsend type breakdown mechanism is absent in the liquid phase of these elements. Index Terms--Liquid helium, breakdown, liquid neon, delocalized electrons, heat of vaporization, Townsend process, electron multiplication, radiation.

Although brown rice (BR) contains significantly higher levels of nutrients than the traditionally used polished white rice (WR), its consumption among the population is still not noteworthy. WR and BR are essentially same grain. The only difference between the two is the application of an exhaustive milling procedure during the processing of WR that removes all other layers of the grain except the portion of its white endosperm. BR, on the other hand, is prepared by removing only the outer hull of the rice seed. Thus, in addition to its inner endosperm, the bran and germ are also left on the BR. Hence, BR retains all its nutrients, including proteins, lipids, carbohydrates, fibers, vitamins, minerals, tocopherols, tocotrienols, γ-oryzanol, and γ-aminobutyric acid (GABA) packed into the bran and germ of the seed. Since BR tastes nutty and takes longer to cook than WR, it is not appreciated by the consumers. However, these problems have been circumvented using non-thermal ultra-high hydrostatic pressure (UHHP)-processing for the treatment of BR. A superior modification in the physicochemical and functional qualities of UHHPBR, along with its ability to curb human diseases may make it a more palatable and nutritious choice of rice over WR or the untreated-BR. Here, we have reviewed the mechanism by which UHHP treatment leads to the modification of nutrients such as proteins, lipids, carbohydrates, and fibers. We have focused on the effects of rice on cell and animal models of different conditions such as hyperlipidemia, diabetes, and hypertension and the possible mechanisms. Finally, we have emphasized the effects of UHHPBR in human cases with rare conditions such as osteoporosis and brain cognition − two age-related degenerative diseases of the elderly population. [ABSTRACT FROM AUTHOR]

Optical and electrical properties of molecularly dope multilayered heterostructures of conducting polymers are analyzed. These polymers were prepared by alternative doping of a substrate into a solution of a negatively charged conducting polymer and a mixed solution of a positively charged conducting polymer and a positively charged porphyrin. Further, the doping effect was explained in terms of effective photoinduced charge separation at the interfaces between negatively and positively charged conducting polymers as well as at the interface between porphyrin derivative and conducting polymers. The results are discussed.

Research was conducted to examine photoinduced dichroism and optical anisotropy in two comb-like liquid-crystalline copolymers with azobenzene chromophores in their side chains. Experiments were carried out using both chloroform solution and very thin spin-coated films. Results demonstrate that polymer I displayed no dichroism at all while its optical anisotroppy may be accounted for by a slow chromophore reorientation. A reorientation of the mesogenic groups was observed in copolymer II at the stage of the cis isomer formation only.

The mechanical vibrations of a freely suspended (FS) ferroelectric liquid-crystal film was examined. Results show that the mechanical vibration of the FS film of the ferroelectric liquid crystal is effectively excited upon excitations by sound irradiation and by electric-field application. Findings also suggest that there are different oscillating modes of the FS film for both excitations since observations made on resonance vibrations showed different light reflection patterns for both excitations.

Electrogenerated chemiluminescence (ECL) of poly(3-hexylthiophene and poly(2-methoxy-5-dodecyloxy-p-phenylenevinylene) has been studied comparatively in an electrolytic solution. The polarity dependence of the ECL comes from the difference in the kinetics of the electrochemical p- and n-type doping/undoping reactions.

A study was conducted of new photovoltaic devices based on donor-acceptor molecular and conducting polymer systems. The findings indicate that selective doping can provide low serial resistance and form internal fields for the collection of charges. In undoped parts, there was effective photogeneration of excitons. Further studies are recommended to maximize the potential of these new photocells.

Vapor-deposited multilayer structure was used to fabricate multicolor-emitting organic electroluminescent diodes. Multicolor emission was made possible by two types of layer structure. In the Type I devices, opposite polarity of electric field was applied to alter emission colors. In the Type II devices, different strength and polarity of electric field was applied to alter emission colors.

The vacuum evaporation technique was used to fabricate electroluminescent (EL) diodes utilizing metal-free phthalocyanine. The analysis included the EL characteristics of the EL diodes depending upon metals of the cathode electrode and the diodes' characteristics. The results indicate that the infrared electroluminescence resulted from the radiative transition corresponding to the Q band of H2Pc.

A conducting polymer with highly extended conjugated bonds in its main chain becomes fusible and also soluble in common solvents after the introduction of long side chains, such as alkyl, as a substituent. Because these liquid conducting polymers and oligomers have much smaller band gaps than those of conventional organic liquids, they exhibit relatively high electrical conductivity and also interact with visible light. Therefore, these liquid conducting polymers can be used effectively for fundamental research to clarify the electronic state and transport processes in dielectric liquids. Novel anomalies in electrical conductivity, photoconductivity and luminescence also have been observed in these liquids, and are discussed in terms of the fluctuation of electronic band gap and the interchain interaction, which depends on alkyl side chain length and on its conformation, and therefore on temperature. The unique applications of these liquid conducting polymers and solutions are also discussed. Characteristics of the interface between conducting polymer and dielectric liquids are also found and discussed in terms of electron scavenging of C[O.sub.2] in liquid and C[O.sub.2] fixation.

The effect of doping and electronic states on the electrochemical, optical and mechanical properties of poly(3-phenylthiophene) (P3PT) during electrochemical p-tye doping is discussed. The band gap of P3PT was evaluated to be 2.0 eV. Polaron and bipolaron models were used to interpret the results of the doping experiments. The stability of the P3PT dopant and the potential of n-type doping in P3PT were confirmed.