a new polymorph crystalline silica composition having uniform pore dimensions were synthesized by calcining a crystalline hydrated alkyl-ammonium silicate. the pore dimensions approximately were 6 angstrom for silicalite-1 and 11 angstrom for silicalite-2 units. the silicalite-1 was prepared hydrothermally at a ph of about 10 from a reaction mixture consist of water, amorphous silica and a quat...

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background: the term crystallized silica refers to the crystallized form of sio 2 and quartz, the most frequency composition in the earth’s crust that can cause silicosis and lung cancer through occupational exposure and inhalation of its large quantities. methods: occupational exposure of workers in pakdasht, iran, in 2011 was investigated in four different casting processes in small foundries...

The addition of a water-clear extract of pneumococci to homologous antiserum produces a voluminous precipitate which carries down with it the agglutinins and practically the totality of the protective bodies against pneumococcus infection in animals. This precipitate when washed and resuspended in saline solution to the original volume of serum protects as well as the whole serum. The protein c...

A 10 % solution of silver nitrate in 10 % acetic acid has been widely used to show the presence of ascorbic acid in microscopical preparations (Bourne, 1936; Giroud, 1938). When there is ascorbic acid in the cells a black precipitate of metallic silver is obtained. This precipitate is often observed to be on or in the Golgi material, and it has been supposed that where this is the case the asco...

The effect of Mo on the microstructure evolution and coarsening kinetics of c0 precipitates in the Ni–Al–Mo system is studied using phase-field simulations with inputs from thermodynamic, kinetic and lattice parameter databases. For alloys of different compositions, the precipitate morphology and the statistical information of precipitate sizes are predicted as a function of annealing time. It ...

Precipitation process in an A1-0.25 wt.%Sc alloy aged at 573 K has been investigated by resistivity and hardness measurements, transmission electron microscopy, and atom-probe field ion microscopy. It was found that the equilibrium A13Sc phase particles precipitate homogeneously from the begining. The particles coarsen following the Lifschitz-Wagner rule after the completion of the nucleation-a...

1. Salt-soluble rat skin collagen was precipitated from solution at neutral pH and 37 degrees . On cooling, a portion of the collagen returned into solution. The fractions were separated, the supernatant was concentrated and the precipitate was redissolved in dilute acetic acid. 2. Solutions of supernatant and precipitate were subjected to the same fractionation procedure, giving four fractions...

This paper focuses on the modeling of heat and mass transfer in precursor containing droplets injected into a plasma jet and the estimation of precipitate formation in these droplets from the solute. A hybrid model is employed where the plasma temperature and velocity fields are obtained from previous experimental results and the heat and mass transfer around droplets are modeled. The precipita...

The critical resolved shear stress of an Al 4 wt. % Cu alloy containing a homogeneous distribution θ′′ precipitates was determined by means dislocation dynamics simulations. size distribution, shape, orientation and volume fraction the in were obtained from transmission electron microscopy observations while parameters controlling dislocation/precipitate interactions (elastic mismatch, transfor...