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Abstract: We prove the existence of at least one weak solution for the \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$p(x)$$\end{document}-Curl systems with nonstandard growth conditions. The proof of our main result uses Ekeland’s variational method.

In order to investigate the effects of nitrogen dilution on combustion behaviour of syngas flames, a model combustor with optical access for swirl non-premixed flames was developed. Experimental results from planar laser-induced fluorescence (PLIF) of OH and particle image velocimetry (PIV) are presented. The syngas consists of hydrogen and carbon monoxide of volume fraction ratio kept at 0.78. Up to 60 per cent (by volume) of nitrogen was added into syngas, as well as reference fuels including methane, hydrogen, and carbon monoxide, for dilution. Flow fields obtained by PIV reveal that the averaged typical swirling flow structure is not influenced by dilution content, which has more effect on turbulence intensities in recirculation zones and shear layers. Additionally, analysis of reaction zones and regions of burnt gas from OH-PLIF measurement shows that although syngas flame burns closer to fuel spray exit than methane, the latter shows more combustion stability, probably because of the different stabilization mechanisms for these two flames. With less support from hot burned gases in recirculation zones, the content of hydrogen plays a crucial role in syngas flame stabilization. Experimental results also imply that the increase of dilution content in fuel leads to less flame opening angle and thinner flame base.

InSnZrO thin films were deposited on glass substrates by magnetron sputtering with an indium‐tin‐oxide (ITO) target and a zirconium target. X‐ray diffractometry (XRD), atomic force microscopy (AFM), and transmission electron microscopy (TEM) revealed that InSnZrO thin films had better crystalline structure, larger grain size, and lower surface roughness than ITO thin films. Zr doping markedly improved the optical–electrical characteristics. In comparison with ITO thin films, the resistivity of InSnZrO thin films deposited at room temperature decreased from 6.24 × 10−3to 2.20 × 10−3Ω cm, and the maximum optical transmittance in the visible range was enhanced from 53.7 to 66.1%. The thin films showed an obvious Burstein–Moss effect with substrate temperature. Moreover, the direct transition model showed a wider optical bandgap of InSnZrO thin films than that of ITO thin films. As a result, InSnZrO thin films prepared by cosputtering revealed better overall properties than traditional ITO thin films.

Abstract: The present paper reports on an experimental study to determine the effect of humidity on the flow field and the flame stability limit in turbulent non-premixed flame, and examines the dynamical behavior of the unsteady aerodynamic flow structures observed on a bluff-body burner at both humid and non-humid air combustion states. Particle image velocimetry (PIV) is used to capture the instantaneous appearance of vortex structures and obtain the quantitative velocity field. Streamlines and velocity contours analysis are used to identify specific flame structures and reveal the effect of steam added on the vortex structure. The results show both central fuel penetration limit and partially quenching limit in the humid air case reduce. The decrease in the critical penetration limit is primarily attributed to a reduction in momentum of the humid air. The flamelet concepts are applied to discuss the partially quenching limit in the blue neck region. The analysis reveals that the large decrease in the partially quenching limit is due to the increase in chemical reaction time of the humid air combustion.

Gold electrodes were modified with short oligonucleotides in order to facilitate the electron transfer to the small redox protein cytochrome c. DNA immobilization was followed by impedance spectroscopy. The electron exchange was found to be quasi‐reversible for both the protein in solution or adsorbed at the electrode surface. Variations of base sequence or structure (DNA‐PNA hybrids) of the nucleic acid promoter layer did not significantly change the electron transfer rate constant which was in the range of 0.2–1×10−2cm/s. Cytochrome c adsorbed at low ionic strength was coupled to molecules in solution such as superoxide or laccase. Aspects of the DNA conductivity and possibilities for DNA detection are also discussed.

Gold electrodes were modified with short oligonucleotides in order to facilitate the electron transfer to the small redox protein cytochrome c. DNA immobilization was followed by impedance spectroscopy. The electron exchange was found to be quasi-reversible for both the protein in solution or adsorbed at the electrode surface. Variations of base sequence or structure (DNA-PNA hybrids) of the nucleic acid promoter layer did not significantly change the electron transfer rate constant which was in the range of 0.2–1×10^–2 cm/s. Cytochrome c adsorbed at low ionic strength was coupled to molecules in solution such as superoxide or laccase. Aspects of the DNA conductivity and possibilities for DNA detection are also discussed.

Cytochrome c′ from Rhodocyclus gelatinosuswas immobilized at a mercaptosuccinic acid modified gold electrode for the first time and the electrochemical behavior was characterized. The conditions of protein adsorption were investigated. Buffer and pH variations indicated a mainly nonionic nature of interaction. The heterogeneous electron transfer rate constant of the immobilized protein was determined (ks=30 s –1). The adsorption was found to be stable in protein‐free solution for about one week. The immobilized cytochrome c′ was accessible for nitric oxide molecules in solution. The interaction resulted in an enhanced reduction current in the cyclic voltammogram. When polarized at –220 mV (vs. Ag/AgCl) the electrode current showed a linear dependence upon NO concentration. The signal was proven to be sensitive within the nanomolar range.

A superoxide sensor based on immobilized cytochrome c has been applied for short time implantation. It has a “stabilization time” of several minutes and the working stability during implantation allows the investigation of the role of superoxide during ischaemia and reperfusion. Its current output is in the pA range.

We have previously reported that interleukin-1-induced proliferation of thymocytes is accompanied by the appearance of [3H]morphine binding sites on these cells. In the present study, we have characterized these binding sites. They differ from classical opioid receptors in the brain in several ways, including: 1) lack of stereoselectivity; 2) relatively low affinity (Kd = 50 nM) and high capacity (Bmax = 3 pmol/mg of protein); 3) binding is strongly inhibited by Ca++, Mg++, Mn++ and Cl- ions and 4) binding is inhibited by proteinase K or E and by phospholipase A2 but not trypsin treatment of thymocyte membranes. The binding sites, which were found largely on the CD4+ subset of T-cells, also showed a preference for opioid alkaloids over peptides. These [3H]morphine binding sites may mediate a negative feedback effect on interleukin-1-induced proliferation of thymocytes in vivo.

Rat brain membranes exhibiting stereospecific opiate binding activity were solubilized by sonication and detergent treatment. The active material could be bound to an affinity column containing 6-succinylmorphine but could not be eluted with free agonist. Although two protein peaks could be eluted with NaCl, neither possessed binding activity; however, one of the peaks (A), in combination with an acidic lipid fraction, eluted subsequently from the column, showed stereospecific binding. Opiate ligands of the mu type bound to this protein/lipid mixture with an order of affinities closely correlating with those of the original membrane but one to two orders of magnitude lower; binding of delta, kappa, and sigma prototype opioids was considerably less. The protein/lipid mixture also competed with the membranes for mu ligands. These results suggest that the isolated protein-lipid complex may be a component of the opiate receptor and, specifically, the mu receptor or binding site. However, because of the lower affinities of mu opiates for this complex, it is conceivable that some essential membrane component is still missing. Preliminary analysis of peak A indicates that it contains a broad spectrum of protein bands, but it remains to be seen which of these are essential for activity.

A mu-opioid-specific receptor was purified to apparent homogeneity from rat brain membranes by 6-succinylmorphine affinity chromatography, gel filtration, wheat germ agglutinin affinity chromatography, and isoelectric focusing. The purified receptor had a molecular weight of 58,000 as determined by NaDodSO4/polyacrylamide gel electrophoresis and was judged to be homogeneous by the following criteria: (i) a single band was detected by autoradiography after NaDodSO4/polyacrylamide gel electrophoresis of 125I-labeled receptor and (ii) the purified preparation had a specific opioid-binding activity of 17,720 pmol/mg of protein, close to the theoretical value. In addition, the Mr 58,000 value agrees closely with that determined by covalently labeling purified receptor with bromoacetyl-[3H]dihydromorphine or with 125I-labeled beta-endorphin and dimethyl suberimidate.