Hydrocracking Marlim vacuum residue with natural limonite. Part 2: experimental cracking in a slurry-type continuous reactor

Disposable Australian iron-slurry (AL) and NiO-MoO₃-Al₂O₃ (NiMo) catalysts were used in hydrocracking experiments to convert Marlim vacuum residue (ML-VR) in a slurry-bed continuous flow reactor at temperatures of 440-460 °C, under a hydrogen pressure of 14.7 MPa and an LHSV of 0.5. The degree of conversion ranged from 54 to 83%, depending on the reaction temperature and catalyst used, with AL giving more complete conversion than NiMo. AL also proved more active in the removal of nickel. Hydrogen consumption was linearly correlated with conversion regardless of the catalyst used.     

Frenkel pair accumulation induced crystallization of amorphous MgAl2O4

The epitaxial and homogeneous irradiation induced re-crystallization of amorphous MgAl₂O₄ was studied by means of continuous Frenkel pair accumulation in the molecular dynamics framework. Present results point out that the re-crystallization induced by Frenkel pair accumulation appears in both cases to be thermally enhanced but non diffusive. It is governed by a local rearrangement of each point defect in the homogeneous case, while spontaneous Frenkel pair recombination process in the crystalline part or at the interface drives the re-crystallization in the epitaxial case.     

Effect of catalyst combination on growth of single-walled carbon nanotubes

A new effective catalysts combination of iron — nickel for alcohol CVD technique was found. This catalyst catalyzed well as well as the typical catalyst of iron — cobalt catalysts, but gave a different diameter distribution. Calculating their electrical density of states under the assumption of their solid lattice structures, the result was fairly consistent with experimental results. The number of electrical states near Fermi level that is considered to be important for catalytic reaction is enough and the DOS of iron – nickel catalyst was quite similar to that of cobalt unlike manganese – copper catalyst. Consequently, a blend of catalysts that has a similar DOS to cobalt and has enough states near the Fermi level can be a good catalyst for alcohol CVD.     

Electrolytic removal of ammonia from brine wastewater: scale‐up,operation and pilot‐scale evaluation

Brine wastewater with a high ammonia content from an iodine processing plant (commonly called kansui in Japan) was treated by electrolysis. The system, which can be considered as an indirect electrolytic treatment process, generates chlorine at the anodes and initiates the formation of mixed oxidants like hypochlorous acid. The oxidants then act as agents for ammonia destruction. Laboratory‐scale experiments showed that high ammonia concentrations (as much as 200 mg dm^?3) could be completely removed within a few minutes, and could be considered a good alternative for efficient ammonia removal from saline wastewaters. From laboratory‐scale experiments in the batch and continuous modes, the charge dose was analyzed and used as the operating and scale‐up factor. The value of the charge dose was not severely affected by changes in operating conditions such as electrode spacing and temperature. The charge dose from batch and continuous runs was found to be in the range of 23 C (mg NH₄‐N removed)^?1 to 29 C (mg NH₄‐N removed)^?1. Using the charge dose obtained from laboratory‐scale continuous electrolysis experiments as the scale‐up factor, a pilot‐scale reactor was designed, and the operating conditions were calculated. In the pilot‐scale reactor tests at different flow rates, the effluent ammonia concentrations were reasonably close to the calculated values predicted from the charge dose equation. Copyright © 2004 Society of Chemical Industry     

Inhibitory effects of proadrenomedullin N-terminal 20 peptide on antidiuresis and norepinephrine overflow induced by stimulation of renal nerves in anesthetized dogs

In an earlier study, we demonstrated that chronic ethanol (EtOH) exposure down-regulated the cannabinoid receptors (CB1) in mouse brain synaptic plasma membrane. In the present study, we investigated the effect of chronic EtOH on the formation of anandamide (AnNH), an endogenous cannabimimetic compound, and its precursor N-arachidonoylphosphatidylethanolamine (N-ArPE) in SK-N-SH cells that were prelabeled with [3H]arachidonic acid. The results indicate that exposure of SK-N-SH cells to EtOH (100 mM) for 72 h significantly increased levels of [3H]AnNH and [3H]N-ArPE (p < 0.05) (1.43-fold for [3H]AnNH and 1.65-fold for [3H]N-ArPE). Exposure of SK-N-SH cells to EtOH (100 mM, 24 h) inhibited initially the formation of [3H]AnNH at 24 h, followed by a progressive increase, reaching a statistical significance level at 72 h (p < 0.05). [3H]N-ArPE increased gradually to a statistically significant level after 48 and 72 h (p < 0.05). Incubation with exogenous ethanolamine (7 mM) and EtOH (100 mM, 72 h) did not result in an additive increase in the formation of [3H]AnNH. The formation of [3H]AnNH and [3H]N-ArPE by EtOH was enhanced by the Ca2+ ionophore A23187 or by the depolarizing agent veratridine and the K+ channel blocker 4-aminopyridine. Further, the EtOH-induced formation of [3H]AnNH and [3H]N-ArPE was inhibited by exogenous AnNH, whereas only [3H]AnNH formation was inhibited by the CB1 receptor antagonist SR141716A and pertussis toxin, suggesting that the CB1 receptor and G(i/o) protein mediated the regulation of AnNH levels. The observed increase in the levels of these lipids in SK-N-SH cells may be a mechanism for neuronal adaptation and may serve as a compensatory mechanism to counteract the continuous presence of EtOH. The present observation taken together with our previous results indicate the involvement of the endocannabinoid system in mediating some of the pharmacological actions of EtOH and may constitute part of a common brain pathway mediating reinforcement of drugs of abuse including EtOH.     

Polymerization of β-lactoglobulin and bovine serum albumin at oil-water interfaces in emulsions by transglutaminase

Polymerization of β-lactoglobulin and bovine serum albumin at the oil—water interfaces in n-tetradecane-in-water emulsions induced by the transglutaminase reaction was studied. The emulsions were incubated with transglutaminase for various times, and adsorbed and unadsorbed protein fractions at the oil—water interfaces were analyzed by sodium dodecyl sulfate—polyacrylamide gel electrophoresis. While only monomers were detected in the unadsorbed fractions, polymers were observed in the adsorbed fractions of the both proteins. The sizes and amounts of the polymers increased with incubation time. The incubation with transglutaminase caused much flocculation of the emulsion stabilized by β-lactoglobulin. An increase in viscosity was also observed with the flocculation. The flocculation was probably initiated by the formation of ε-(γ-glutamyl)-lysyl isopeptide bonds between β-lactoglobulin molecules adsorbed on different oil droplets. In the case of the emulsion stabilized by bovine serum albumin, however, the flocculation and the increase in viscosity occurred to only limited extents by the transglutaminase reaction. This suggests that ε-(γ-glutamyl)-lysyl isopeptide bonds induced by the transglutaminase reaction were formed only between neighboring molecules of bovine serum albumin on the same droplet.     

Expression of mRNA encoding IFN alpha in macrophages stimulated with Lactobacillus gasseri

The N7 of guanine is thought to be the primary target for adduct and crosslink formation between cisplatin and DNA. However, reactive sites in DNA other than the N7 of guanine may also participate in the formation of adducts with cisplatin. The possibility that these interactions arise and form DNA polymerase blocking lesions was investigated by primer extension reactions with Taq DNA polymerase. To differentiate between damage produced at relatively weak sites from those formed at the N7 of guanine, a modified DNA template was synthesised with the N7 of guanine replaced with a carbon atom. This was achieved in a PCR designed to incorporate 7-deazaguanine instead of normal guanine. The sequence specificity of cisplatin damage in the modified and unmodified DNA substrates was compared (after linear amplification) by DNA sequencing gel analysis. For concentrations of cisplatin (1 to 5 microM) that induce blocking lesions in normal DNA, no significant damage was observed in the modified DNA. This confirmed that the N7 of guanine is the major site of adduct formation in normal DNA. At higher concentrations of cisplatin (50 microM and 100 microM), lesions were found at AA dinucleotides and other novel sites in the modified DNA. These results indicate that the N7 of guanine is not required in the formation of some cisplatin adducts.     

Study for improvement of solar cell efficiency by impurity photovoltaic effect

This paper is to study for efficiency improvement of solar cells by utilizing impurity traps introduced in the band gap of semiconductor, that is, impurity photovoltaic (IPV) effect. It is revealed theoretically that there is a certain energy range where impurity-traps act as stepping stones in two-step excitation of electrons from the valence band to the conduction band under suppression of carrier recombination through such traps. Indium is selected as one of proper impurities that satisfy this condition in crystalline silicon, and theoretical prediction is experimentally verified. A good agreement between theory and experiment is obtained concerned with photoconductive properties. It is concluded that the IPV effect is useful to improve the cell efficiency.