We have recently developed a method for the analysis of toxins in single specimens of the mush­ room Amanita phalloides (Fr.) Seer.1. Separation of the different toxins was achieved by column chro­ matography, on Sephadex LH20 in water, of a methanolic extract of fresh or dried mushrooms, followed by further purification on thinlayers of silica gel, spectrophotometric evaluation, and, final­ ly...

Raman spectra of monoclinic Fo90 hydrous wadsleyite with 2.4 wt% H2O have been measured in a diamond-anvil cell with helium as a pressure-transmitting medium to 58.4 GPa at room temperature. The most intense, characteristic wadsleyite modes, the Si–O– Si symmetric stretch at 721 cm 1 and the symmetric stretch of the SiO3 unit at 918 cm , shift continuously to 58.4 GPa showing no evidence of a f...

Exposure of enynes containing a hydroxyl group at one of the propargylic positions to catalytic amounts of either PtCl2 or (PPh3)AuCl/AgSbF6 results in a selective rearrangement with formation of bicyclo[3.1.0]hexan-3-one derivatives. The same products are obtained by a "one-pot" process on treatment of an alkynal with allylchlorodimethylsilane (4) and PtCl2 via a reaction cascade involving an ...

[1] Raman spectra of a single crystal of hydrous Fo89ringwoodite have been measured in a diamond-anvil cell at room temperature to 60 GPa. Strong peaks corresponding to asymmetric and symmetric stretching vibrations of the SiO4 tetrahedra are observed at 796 and 841 cm 1 respectively. Additional bands occur in the range 709–939 and 100–250 cm . The SiO4 stretching modes of the spinel structure ...

In the subapical third internode of 7-day-old etiolated pea seedlings, the magnitude of phototropic curvature in response to continuous unilateral blue illumination is increased when seedlings are pre-exposed to brief red light. The effect of red light on blue light-induced phototropism becomes manifest maximally 4 or more hours after red illumination, and closely parallels the promotive action...

It has been suggested that in systemic sclerosis (SSc) the primary fault is in the microcirculation.' If this were so, then topical glyceryl trinitrate (GTN) might favourably influence skin blood flow and elasticity in areas of sclerodermatous skin change. Ten patients (three men, seven women; median age 48 years, range 24-70) fulfilling the American Rheumatism Association criteria for SSc2 wer...

A mathematical model describing the erosion or leaching of a solid material by flowing fluid in column is developed. This involves an advection-diffusion equation coupled to linear kinetic reaction mass transfer between and fluid. Two specific cases are analysed, first where extracted has same saturation solubility rate throughout process, second switches after certain amount erosion. In case t...