A CaCO3-crystal-growth inhibitor was isolated from human pancreatic stones by using EDTA demineralization, followed by DEAE-Trisacryl chromatography. The isolated inhibitor was found to be a phosphoglycoprotein with Mr 14017 and having an unusual chemical composition. It is characterized by a high (42%) acidic amino acid content, but lacks methionine and gamma-carboxyglutamic acid. The protein ...

The paper presents the results of studies on the effect of the AlSi17Cu5 alloy overheating to atemperature of 920°C and modification with phosphorus (CuP10) on the resultingmechanical (HB, Rm, R0.2) and plastic (A5 and Z) properties. It has been shown that, so-called, "timethermal treatment" (TTT) of an alloy in the liquid state, consisting inoverheating the metal to about 250°C above T liq,hol...

[1] This paper reports the first measurements of the saturation state of low molecular weight alkyl nitrates (methyl, ethyl, isopropyl, and n-propyl nitrate) in the tropical Pacific Ocean. These compounds were supersaturated with saturation anomalies as high as 2000%. Air/sea flux estimates based on these measurements suggest that surface ocean emissions are sufficient to account for observed l...

Fluorescence quenching of pyranine by tryptophan, phenylalanine, and nicotinic acid was investigated by using steady state and time resolved fluorescence spectroscopy. On a comparative basis, nicotinic acid is a very strong quencher of pyranine fluorescence, tryptophan is a moderate quencher and phenylalanine is a weak quencher. The strong quenching is the result of the hydrogen bonding complex...

Chitosan based nanofibers containing carbon nanotubes were applied on AZ31 magnesium alloy via electrospinning. The magnesium substrate was initially anodized in a NaOH solution in order to improve the adhesion between the coating and substrate. Electrospinning parameters were optimized and homogenous nanofibers composite coatings were produced. Addition of carbon nanotubes reduced the size of ...

Nanostructured Al and Al-Mg (Mg 30 wt. %) powders with the mean crystallite sizes of 42 and 11 nm were prepared through the solid state ball milling technique. The milling process was performed for various times up to 12 h in argon atmosphere and the synthesized powders were in detail characterized by different techniques. The effect of milling time and Mg addition on the size, morphology, chem...