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Samples of Haipao from three cities of Taiwan were analyzed for their microbial population. Two species of acetic acid bacteria and three species of yeast were isolated from tea fungus Haipao using appropriate isolation media. The isolated bacteria were identified asAcetobacter acetiandAcetobacter pasteurianus, based on their biochemical properties, and compared with those of the type strains of the genusAcetobacter. The yeasts wereSaccharomyces cerevisiae, Zygosaccharomyces bailii, andBrettanomyces bruxellensisaccording to conventional phenotypic characterization combined with the Yeast Identification Program. The brew broth analyzed by high−performance liquid chromatography (HPLC) was shown to contain glycerol, acetic acid and ethanol. The symbiosis phenomenon between the yeast andAcetobacterwas studied. It was found that the autoclaved yeast cells and ethanol produced by yeasts were helpful forAcetobacterto grow or produce acetic acid. The acetic acid produced byAcetobactercould stimulate the yeast to produce ethanol. The ethanol and acetic acid produced by yeasts andAcetobactermight prevent the competition from other micro-organisms.

Obtention du dimethyl-3,3 phenyl-1indanol. Mecanisme. Le rendement quantique est de 0,04 dans les hydrocarbures alors qu'il est egal a 1 dans le methanol

Single crystals of 4-phenyl-1,2,3,5-dithiadiazolium trithiatriazinide , prepared by the reduction of S5N5+AlCl4− in SO2 with , contain a trace paramagnetic impurity which is shown by EPR spectroscopy to be the dithiadiazolyl free radical . The g and 14N hyperfine tensors of the radical were deduced from measurements made throughout three mutually orthogonal planes of crystallographically aligned specimens: g = (2.0011, 2.0075, 2.0197); 14N(2) = (37.1, 11.3, 3.4 MHz.). Within experimental error, the two nitrogen hyperfine interaction tensors are collinear and have their maximum principal value aligned parallel to gmin and perpendicular to the plane of the host cation. The results are interpreted in terms of a planar π-radical which substitutes for the planar host cation, and which has considerable unpaired spin density in N(2px) atomic orbitals directed perpendicular to the heterocyclic ring.

Ortho-disubstituted aromatics with bulky substituents are distorted so that the substituents are above and below the approximate plane of the aromatic system. This introduces chirality which was observed by proton resonance spectroscopy with and without the use of a chiral shift reagent. The more nearly planar naphthalene systems invert their chiral configurations more rapidly. Crystals of 1,2-benzenediacetic acid, α,α,α′,α′-tetramethyldimethyl ester are monoclinic, space group A2/a with a = 10.665(3), b = 8.467(2), c = 17.198(4) Å and β = 105.94(2)°. The torsion angle between the 1,2 substituents is 12.1°. Crystals of 2,3-naphthalene diacetic acid, α,α,α′,α′-tetramethyldimethyl ester are also monoclinic, space group P21/c with a = 9.0992(14), b = 18.849(3), c = 11.319(2) Å and β = 113.88(1)°. The analogous torsion angle in this case is 8.9°.

Successive intravenous injections of nicotine cause a biphasic block of the adrenal medulla of the cat. During the early phase the adrenal glands fail to respond to any stimulant; however, during the late, non-depolarizing phase the glands respond to non-nicotinic agents (5-hydroxytryptamine, bradykinin and pilocarpine) and to potassium chloride at a time when there is a pronounced and insurmountable antagonism to nicotinic agents. During this late phase of the block the effects of most of these agents are enhanced, although the sensitivity to noradrenaline is not. The enhancement is abolished by hexamethonium, which lacks any effect on the sensitivity to noradrenaline. The results obtained with the muscarinic agent, pilocarpine, support the earlier postulate that transmission of impulses from the splanchnic nerve, as observed during the late phase of the block by nicotine, is mediated by muscarinic mechanisms sensitized by nicotine.

Publisher Summary In vitro studies demonstrated that the enhanced synthesis of norepinephrine in peripheral nervous tissue, which occurs during nerve stimulation, is the result of increased activity of the enzyme tyrosine hydroxylase in the intact tissue. Because this effect can be prevented by the addition of norepinephrine to the medium that bathes the stimulated tissue, it was presumed that the activation of tyrosine hydroxylase is a consequence of reduced end-product feedback inhibition. Experiments suggest that the activation of tyrosine hydroxylase during nerve stimulation might be mediated by a different process, because the addition to the incubation medium of the synthetic pterin cofactor, 6,7-dimethyl-5,6,7,8-tetrahydropterin (Me2PtH4), which is able to antagonize competitively the inhibition of tyrosine hydroxylase by norepinephrine, does not eliminate the enhanced synthesis of norepinephrine associated with nerve stimulation of the isolated, intact vas deferens preparation. Results suggested that tyrosine hydroxylase is activated during nerve stimulation by a mechanism that is unrelated to an altered affinity for either norepinephrine or pterin cofactor.

Obtention du dimethyl-3,3 phenyl-1indanol. Mecanisme. Le rendement quantique est de 0,04 dans les hydrocarbures alors qu'il est egal a 1 dans le methanol

This paper introduces an experimental technique and associated data analysis procedure for studying the shear dependent viscosity of oils containing polymers at shear rates up to 10 6 s −1 and temperatures up to 170°C, conditions which are typically experienced in operating engines. The experimental apparatus is a capillary viscometer with a controlled nitrogen gas pressure as the driving force and uses constant volume efflux bulbs to measure the oil flow rate. The main contribution of this work is the coupling of experimental calibration measurements and a theoretical analysis to develop a calibration procedure which can be used to extract accurate high-shear rate viscosity data from capillary viscometer measurements when the fluid viscosity is being influenced by temperature, pressure, and shear rate.