Synthesis of spherical LiMn2O4 microparticles by a combination of spray pyrolysis and drying method

Lithium manganese oxide (LiMn₂O₄) has been synthesized by a spray pyrolysis method from the precursor solution; LiNO₃ and Mn(NO₃)₂·6H₂O were stoichiometrically dissolved into distilled water. The synthesized LiMn₂O₄ particles exhibited a pure cubic spinel structure in the X-ray diffraction (XRD) patterns, however they were spherical hollow spheres for various concentrations of precursor solution. Thus, the as-prepared LiMn₂O₄ particles were then ground in a mortar and dispersed into distilled water. To make a well dispersed slurry solution, a dispersion agent was also added into the slurry solution. The LiMn₂O₄ microparticles with a spherical nanostructure were finally prepared by a spray drying method from the slurry solution. The tap density of the LiMn₂O₄ microparticle prepared by a combination of spray pyrolysis and drying method was larger than that by a conventional spray pyrolysis method.The as-prepared samples were sintered at 750 °C for 1 h in air and used as cathode active materials for lithium batteries. Test experiments in the electrochemical cell Li|1 M LiClO₄ in EC:DEC = 1:1|LiMn₂O₄ demonstrate that the sample prepared by the present method is a promising cathode active material for 4 V lithium-ion batteries at high-charge-discharge and elevated temperature operation. The LiMn₂O₄ compounds by the combination of spray pyrolysis and drying method are superior to that by the conventional spray pyrolysis method in terms of electrochemical characteristics and tap density.     

UV-induced switching behavior of novel fluoroalkyl end-capped vinyltrimethoxysilane oligomer/titanium oxide nanocomposite between superhydrophobicity and superhydrophilicity with good oleophobicity

Fluoroalkyl end-capped vinyltrimethoxysilane oligomer suffered the sol–gel reaction under alkaline conditions in the presence of titanium oxide nanoparticles in tetrahydrofuran to afford the corresponding fluorinated oligomer/titanium oxide nanocomposites[R_F-(VM-SiO₂)_n-R_F/TiO₂] in excellent to moderate isolated yields. These fluorinated composites thus obtained were nanometer size-controlled fine particles, and exhibited good dispersibility and stability in traditional organic solvents except for water. These fluorinated nanocomposites were applied to the surface modification of glass to exhibit not only a completely superhydrophobic characteristic (a water contact angle: 180°) with a non-wetting property against water droplets but also a good oleophobicity imparted by fluoroalkyl segments in the composites on their surface. Of particular interest, we have found that the wettability for water can be switched between superhydrophobicity and superhydrophilicity by alternation of ultraviolet (UV) irradiation and dark storage with keeping a good oleophobicity on the modified surface treated with the anatase-type titanium oxide composite.     

Near-infrared reflection from periodically aluminium-doped zinc oxide thin films

Multilayers of aluminium-doped zinc oxide (Al:ZnO) as a heat-reflection material were prepared by a reactive sputtering method with intermittent Al doping or Al content modulation. A drop in the refractive indices n around the plasma wavelength λ_p of 1456 nm for the optimally-doped Al:ZnO layers formed the periodic distribution of n in the multilayers. The periodic n provided selective reflection of approximately 60% under λ_p and shielded near-infrared solar radiation containing high energy, which was impossible to be reflected from the Al:ZnO monolayer. The selective reflection was accompanied by infrared reflection above λ_p, low emissivity and no subsequent visible reflection, which allowed the multilayers to achieve compatibility between the solar heat gain coefficient of 0.6 and the visible transmittance of nearly 80%.     

Aluminum-doped zinc oxide electrode for robust (Pb,La)(Zr,Ti)O3 capacitors: effect of oxide insulator encapsulation and oxide buffer layer

Conductive aluminum-doped zinc oxide (AZO) was deposited by pulsed laser deposition as top electrodes for chemical solution deposition derived lanthanum modified lead zirconate titanate (PLZT) capacitors. Compared with PLZT capacitors with Pt top electrodes (Pt/PLZT/Pt), PLZT capacitors with AZO as top electrodes (AZO/PLZT/Pt) showed improved fatigue endurance after cycles of 200 kV/cm (10 V) were applied with a 100 μs pulse width at 1 ms intervals. By using a combination of AZO as the top electrode and as a thin buffer layer (10 nm) under PLZT thin films (AZO/PLZT/AZO/Pt), fatigue behavior was also improved compared with the case without an AZO buffer layer. The addition of either an Al₂O₃ or HfO₂ encapsulation layer increased the remnant polarization ratio of PLZT capacitors (after annealing at 200 °C, 1 Torr, 3 % hydrogen atmosphere) to 0.80 and 0.57, respectively, comparing with 0.52 without an encapsulation layer.     

Eviprostat Activates cAMP Signaling Pathway and Suppresses Bladder Smooth Muscle Cell Proliferation

Eviprostat is a popular phytotherapeutic agent for the treatment of lower urinary tract symptoms (LUTS). At present, the signaling mechanisms underlying its therapeutic effects are still poorly understood. Given that cAMP has been reported to suppress cell hyperplasia and hypertrophy in various pathological situations, we asked whether the effect of Eviprostat could be ascribed to the activation of the cAMP signaling pathway. In the study, exposure of cAMP response element (CRE)-secreted alkaline phosphatase (SEAP) (CRE-SEAP)-reporter cells to Eviprostat elevated SEAP secretion, which was associated with an increased phosphorylation of vasodilator-stimulated phosphoprotein (VASP) and cAMP-response element-binding protein (CREB), as well as enhanced expression of CRE-regulated protein connexin43, indicating an activation of the cAMP signaling pathway. Consistent with these observations, Eviprostat-induced expression of Cx43 was abolished in the presence of adenylyl cyclase inhibitor SQ22536 or PKA inhibitor H89, whereas it was mimicked by adenylyl cyclase activator, forskolin. Further analysis demonstrated that Eviprostat significantly potentiated the effect of phosphodiesterase 3 (PDE3) inhibitor, but not that of PDE4 inhibitor, on CRE activation. Moreover, Eviprostat suppressed PDGF-induced activation of ERK and Akt and inhibited cell proliferation and hillock formation in both mesangial cells and bladder smooth muscle cells. Collectively, activation of the cAMP signaling pathway could be an important mechanism by which Eviprostat exerts its therapeutic effects for LUTS.     

Horseradish peroxidase degrades lipid hydroperoxides and suppresses lipid peroxidation of polyunsaturated fatty acids in the presence of phenolic antioxidants

Linoleic acid hydroperoxide (LAOOH) was effectively degraded by horseradish peroxidase (HRP) in the presence of quercetin. Several natural phenolic antioxidants, such as quercetin, capsaicin, and alpha-tocopherol, acted as good hydrogen donors in the peroxidase reaction that occurs during lipid hydroperoxide degradation. However, glutathione, which is a non-phenolic antioxidant that acts as a hydrogen donor for glutathione peroxidase, could not suppress lipid peroxidation in the presence of HRP. Lipid hydroperoxides generated from eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) were also degraded with HRP in the presence of quercetin, and oxidative decomposition of DHA was suppressed by this reaction.     

Caged multiwalled carbon nanotubes as the adsorbents for affinity-based elimination of ionic dyes

Multiwalled carbon nanotubes (MWCNTs) were used as the active elements for the first time for affinity-based elimination of ionic dyes. MWCNTs were encapsulated in cross-linked alginate (ALG) microvesicles using Ba2+ as the bridging ion. The Ba2+-alginate matrix constitutes a cage which holds the physically trapped MWCNTs. The cage carries negative charges on its surface. The cage restricts the access of anions of large molecular weight, such as humic acids, because of electrostatic repulsion. The cage also restricts the access of colloids of large size, because of size exclusion. Ionic dyes partition into the cage and then are captured by MWCNTs probably on the basis of van der Waals interactions occurring between the hexagonally arrayed carbon atoms in the graphite sheet of MWCNTs and the aromatic backbones of the dyes. As a result of these interactions the target species, namely, the ionic dyes, are eliminated efficiently by the MWCNTs of Ba2+-ALG/MWCNT composite adsorbents. The adsorptive capacities for elimination of acridine orange, ethidium bromide, eosin bluish, and orange G (the model species used for this study) were found as high as 0.44, 0.43, 0.33, and 0.31 micromol, respectively, for 1.0 mg of the caged MWCNTs. Adsorptive experiments with carbon nanofibers and activated carbons as the adsorbents were also performed. The MWCNT-based adsorbents provided the best capability for the affinity-based elimination of these targeted species. Biocompatibility experiments performed in vitro and in vivo provided promising results, suggesting potential applications of the caged MWCNTs in in situ environmental remediation.     

A method for inspecting industrial parts surfaces based on an optics model

A new method based on an optics model for highly reliable surface inspection of industrial parts has been developed. This method uses multiple images taken under different camera conditions. Phong's model is employed for surface reflection, and then the albedo and the reflection model parameters are estimated by the least squares method. The developed method has advantages over conventional binarization in that it can easily determine the threshold of product acceptability and cope with changes in light intensity when detecting defects.     

Serum autoantibody to sideroflexin 3 as a novel tumor marker for oral squamous cell carcinoma

The purpose of this study is to establish a tumor marker that can be applied for the early detection and follow-up of oral cancer patients. Employing the proteomic approach using MALDI TOF-MS, 2-DE, patient's sera and culturing cell lines, the serum autoantibodies (autoAbs) were screened and the serum levels were estimated by ELISA. Targeting the tumor cell invasion into the surrounding stromal tissues, MRC-5 human fibroblasts were employed as the target cells and a mitochondrial membrane protein, sideroflexin 3 (SFXN3), was identified. The serum anti-SFXN3-autoAb levels elevated in patients with the oral squamous cell carcinoma significantly: with 77% sensitivity and 89% specificity against control samples. The serum anti-SFXN3-autoAb levels were mildly correlated with the primary tumor sizes, however, the levels were slightly highly elevated in T1 early cancer. An immunohistochemical analysis revealed that the SFXN3 protein is expressed in the stromal fibroblasts between the caner nests and also in the basal layer of the squamous epithelium. Changes in the serum anti-SFXN3-autoAb levels after therapy correlated with the clinical tumor burden. These findings demonstrated that the serum anti-SFXN3-autoAb is worthy of clinical evaluation as a potentially of the novel tumor maker for the early detection of oral squamous cell carcinoma.     

Fundamental Study on Interaction between Top Blown Jet and Liquid Bath

It is important to understand the physical interaction between top‐blown oxygen jets and liquid steel in basic oxygen steelmaking furnaces (BOF). In the present study, cold model experiments and CFD simulations were carried out with single‐ and multi‐hole nozzles and the velocity profiles of jets were successfully simulated. Water model experiments were also performed to study the cavity formation and the spitting phenomena by the impinging jets. The cavity shapes and the spitting behavior were correlated to the top‐blowing conditions by considering the characteristics of multi‐hole nozzle jets.