Test results of a catalytically assisted combustor for a gas turbine

A catalytically assisted ceramic combustor for a gas turbine was designed and tested to achieve low NO_x emissions. This combustor is composed of a burner and a ceramic liner. The burner consists of an annular preburner, six catalytic combustor segments and six premixing nozzles, which are arranged in parallel and alternately. In this combustor system, catalytic combustion temperature is controlled under 1000 °C, premixed gas is injected from the premixing nozzles to the catalytic combustion gas and lean premixed combustion over 1300 °C is carried out in the ceramic liner. This system was designed to avoid catalyst deactivation at high temperature and thermal shock fracture of the ceramic honeycomb monolith of the catalyst. A 1 MW class combustor was tested using LNG fuel. Firstly, NO_x emissions from the preburner were investigated under various pressure conditions. Secondly, two sets of honeycomb cell density catalysts and one set of thermally pretreated catalysts ware applied to the combustor, and combustion tests were carried out under various pressure conditions. As a result, it was found that the main source of NO_x was the preburner, and total NO_x emissions from the combustor were approximately 4 ppm (at 16% O₂) at an adiabatic combustion temperature of 1350 °C and combustor inlet pressure of 1.33 MPa.     

FORMATION MECHANISM OF Tio2 FINE PARTICLES PREPARED BY THE SPRAY PYROLYSIS METHOD

Fine particles of Tio₂ were prepared from titanyl sulfate solution by the Spray pyrolysis Method( SPM) The reaction tube was divided into four zones: drying, dehydration, pyrolysis 1 and pyrolysis 2 zones. Under various reaction temperature and carrier gas flow rate, the mean size and the size distribution of particles collected at different sampling positions along the axial direction of the reactor were compared. The effects of operating conditions of drying, dehydration and subsequent pyrolysis steps on the formation mechanism of Tio₂ fine particles were discussed     

Solid-liquid phase equilibria of (α-methylnaphthalene + β-methylnaphthalene) and (chlorobenzene + bromobenzene) systems under high Pressures

Solid-liquid phase equilibria of the (-methylnaphthalene + -methylnaphthalene) and the (chlorobenzene + bromobenzene) systems have been investigated at temperatures from 278 to 343 K and pressures up to 500 MPa using a high-pressure optical vessel. The uncertainties of the measurements of temperature, pressure, and composition were within ±0.1 K, ±0.5 MPa, and ±0.001 mole fraction, respectively. In both systems, the freezing and melting pressures at a constant composition increase almost linearly with increasing temperatures. In the former system, where the two components can form a solid solution with one another to a limit extent, the eutectic point shifts to a higher temperature and to a -methylnaphthalene-rich composition with increasing pressures. In the latter system, where the two components are completely soluble in each other in the solid phase, the freezing points of all mixtures lie between those of the pure components at each pressure. It is found that the coexistence curves obtained can be expressed by a quadratic equation in pressure.     

Detailed analyses of key phenomena in core disruptive accidents of sodium-cooled fast reactors by the COMPASS code

A five-year research project has been initiated in 2005 to develop a code based on the MPS (Moving Particle Semi-implicit) method for detailed analysis of key phenomena in core disruptive accidents (CDAs) of sodium-cooled fast reactors (SFRs). The code is named COMPASS (Computer Code with Moving Particle Semi-implicit for Reactor Safety Analysis). The key phenomena include (1) fuel pin failure and disruption, (2) molten pool boiling, (3) melt freezing and blockage formation, (4) duct wall failure, (5) low-energy disruptive core motion, (6) debris-bed coolability, and (7) metal–fuel pin failure. Validation study of COMPASS is progressing for these key phenomena. In this paper, recent COMPASS results of detailed analyses for the several key phenomena are summarized. Simulations of GEYSER and THEFIS experiments were performed for dispersion and freezing behaviors of molten materials in narrow flow channels. In particular, the latter experiment using melt–solid mixture is also related to fundamental behavior of low energy disruptive core. CABRI-TPA2 experiment was simulated for boiling behavior of molten core pool. Expected mechanism of heat transfer between molten fuel and steel mixture was reproduced by the simulation. Analyses of structural dynamics using elastoplastic mechanics and fracture criteria were performed for SCARABEE BE+3 and CABRI E7 experiments. These two analyses are especially focused on thermal and mechanical failure of steel duct wall and fuel pin, respectively. The present results demonstrate COMPASS will be useful to understand and clarify the key phenomena of CDAs in SFRs in details.     

Histological features of the vomeronasal organ in the giraffe,Giraffa camelopardalis

The vomeronasal organ (VNO) that preferentially detects species‐specific substances is diverse among animal species, and its morphological properties seem to reflect the ecological features of animals. This histological study of two female reticulated giraffes (Giraffa camelopardalis reticulata) found that the VNO is developed in giraffes. The lateral and medial regions of the vomeronasal lumen were covered with sensory and nonsensory epithelia, respectively. The vomeronasal glands were positive for periodic acid‐Schiff and alcian blue (pH 2.5) stains. The VNO comprises several large veins like others in the order Cetartiodactyla, suggesting that these veins function in a pumping mechanism in this order. In addition, numerous thin‐walled vessels located immediately beneath the epithelia covering the lumen entirely surrounded the vomeronasal lumen. This sponge‐like structure might function as a specific secondary pump in giraffes.     

Blood-Based Biomarkers in Hepatitis B Virus-Related Hepatocellular Carcinoma,Including the Viral Genome and Glycosylated Proteins

Hepatitis B virus (HBV) infection is a major risk factor for hepatocellular carcinoma (HCC) development and is a global public health issue. High performance biomarkers can aid the early detection of HCC development in HBV-infected individuals. In addition, advances in the understanding of the pathogenesis of HBV infection and in clinical laboratory techniques have enabled the establishment of disease-specific tests, prediction of the progression of liver diseases, including HCC, and auxiliary diagnosis of HCC, using blood-based methods instead of biopsies of liver or HCC tissues. Viral factors such as the HBV genotype, HBV genetic mutations, HBV DNA, and HBV-related antigens, as well as host factors, such as tumor-associated proteins and post-translational modifications, especially glycosylated proteins, can be blood-based, disease-specific biomarkers for HCC development in HBV-infected patients. In this review, we describe the clinical applications of viral biomarkers, including the HBV genome and glycosylated proteins, for patients at a risk of HBV-related HCC, based on their molecular mechanisms. In addition, we introduce promising biomarker candidates for practical use, including colony stimulating factor 1 receptor (CSF1R), extracellular vesicles, and cell-free, circulating tumor DNA. The clinical use of such surrogate markers may lead to a better understanding of the risk of disease progression and early detection of HCC in HBV-infected patients, thereby improving their prognosis.     

Characterization of cellulose microbeads prepared by a viscose‐phase‐separation method and their chemical modification with acid anhydride

Chemically modified cellulose microbeads are useful as cosmetic materials. Cellulose microbeads as supports, prepared by a viscose‐phase‐separation method, are monodisperse and spherical. However, cellulose shows only slight hydrophilicity, even though it has three hydroxyl groups per pyranose ring, because cellulose possesses high crystallinity on account of the cellulose II structure derived from hydrogen bonds among the hydroxyl groups. To increase the hygroscopicity of cellulose microbeads, we have carboxylated them with succinic and glutaric anhydrides. Their hygroscopicity increases with the addition of succinoyl and glutaroyl groups. Moreover, we have confirmed the increased hygroscopicity of microbeads with sodium salinization. We have investigated the decomposition of these hydrophilic cellulose microbeads in aqueous buffer solutions and have confirmed that succinoylated cellulose is more readily decomposed than glutaroylated cellulose microbeads in aqueous solutions. On the other hand, to increase the lipophilicity of cellulose microbeads, we have acylated them with acetic and hexanoic anhydrides. Hydrophobizing microbeads with hexanoyl groups provides an affinity to benzene but not to H₂O. In contrast, hydrophobizing with acetyl groups provides affinity not only to benzene but also to H₂O. © 2005 Wiley Periodicals, Inc. J Appl Polym Sci 97: 149–157, 2005     

Polymerization of surface-active monomers: 5. Syntheses and polymerizations of anionic surface-active monomers: sodium di(10-undecenyl)sulphosuccinate and sodium n-undecyl 10-undecenylsulphosuccinate

Novel, anionic surface-active monomers, sodium di(10-undecenyl)sulphosuccinate (DUSS) and sodium n-undecyl 10-undecenylsulphosuccinate (MUSS) were prepared. The monomers were soluble in both water and apolar organic solvents on heating. DUSS and MUSS in water exhibited Kraft points at about 39°C and 48°C, respectively. The critical micelle concentrations for aqueous solutions of DUSS and MUSS at 50°C were determined to be 2.4 × 10⁻⁵ and 1.2 × 10⁻⁵ mol l⁻¹, respectively. Polymerization of the monomers in darkness and under u.v. irradiation at 50°C were studied using three different solvents, namely water, n-hexane and dioxane, giving aqueous micelles (or vesicles), reversed micelles and isotropic solution, respectively. Only traces of polymers were formed for the polymerizations in darkness, while the polymerizations under u.v. irradiation gave polymers, except for the polymerization of MUSS in dioxane. The solvents used for the polymerization were observed to exert an effect on the solubility of the polymers of DUSS and only the polymer obtained from the polymerization in water was soluble in solvents such as water and N,N-dimethylformamide. Thus, the monomer aggregation, especially for the aqueous system, was found to affect the structure of the resulting polymers.     

HIF-1α Dependent Upregulation of ZIP8, ZIP14, and TRPA1 Modify Intracellular Zn2+ Accumulation in Inflammatory Synoviocytes

Intracellular free zinc ([Zn²⁺]_i) is mobilized in neuronal and non-neuronal cells under physiological and/or pathophysiological conditions; therefore, [Zn²⁺]_i is a component of cellular signal transduction in biological systems. Although several transporters and ion channels that carry Zn²⁺ have been identified, proteins that are involved in Zn²⁺ supply into cells and their expression are poorly understood, particularly under inflammatory conditions. Here, we show that the expression of Zn²⁺ transporters ZIP8 and ZIP14 is increased via the activation of hypoxia-induced factor 1α (HIF-1α) in inflammation, leading to [Zn²⁺]_i accumulation, which intrinsically activates transient receptor potential ankyrin 1 (TRPA1) channel and elevates basal [Zn²⁺]_i. In human fibroblast-like synoviocytes (FLSs), treatment with inflammatory mediators, such as tumor necrosis factor-α (TNF-α) and interleukin-1α (IL-1α), evoked TRPA1-dependent intrinsic Ca²⁺ oscillations. Assays with fluorescent Zn²⁺ indicators revealed that the basal [Zn²⁺]_i concentration was significantly higher in TRPA1-expressing HEK cells and inflammatory FLSs. Moreover, TRPA1 activation induced an elevation of [Zn²⁺]_i level in the presence of 1 μM Zn²⁺ in inflammatory FLSs. Among the 17 out of 24 known Zn²⁺ transporters, FLSs that were treated with TNF-α and IL-1α exhibited a higher expression of ZIP8 and ZIP14. Their expression levels were augmented by transfection with an active component of nuclear factor-κB P65 and HIF-1α expression vectors, and they could be abolished by pretreatment with the HIF-1α inhibitor echinomycin (Echi). The functional expression of ZIP8 and ZIP14 in HEK cells significantly increased the basal [Zn²⁺]_i level. Taken together, Zn²⁺ carrier proteins, TRPA1, ZIP8, and ZIP14, induced under HIF-1α mediated inflammation can synergistically change [Zn²⁺]_i in inflammatory FLSs.