Precipitation from Homogeneous Solution

Abstract

VOLUME 2 4, NO. 3, MARCH 1952 459 end points which are close together. When conditions are such that the wings of the curve are actually straight lines, but the end point is very poor, the ordinary method is sometimes superior to the differential method. For slow reactions, the differential method may be inapplicable.A buret is described which can be used either in the normal manner or to deliver solution at a uniform and low rate of addition.

Coprecipitation of uranium and plutonium oxalates using sodium formaldehyde sulfoxylate reduction and diethyl oxalate hydrolysis precipitation

“…An evaluation of various techniques for coprecipitating uranium and plutonium led us to conclude that uranium must first be reduced to U I|+ and plutonium to Pu 3 , and that oxalate precipitates are the most quantitative and crystalline. The usual reductants capable of reducing uranium to U 1 ** are highly electronegative metals whose ions also form insoluble oxalates.…”

“…With uranium-plutonium mixtures, however, the reduction of plutonium to Pu 3 by sodium formaldehyde sulfoxylate is very rapid. When this reaction is initiated, the blue color of Pu 3 is seen immediately and then changes slowly to bluegreen as the uranium is reduced. The complete reduction of plutonium and uranium requires 1 to 2 h in 2M IINOj, the medium used in our preparation.…”

Preparation of Phosphor Fine Particles for Mercury-Free Lamps by Using Liquid-Phase Synthesis Method

“…The liquid phase synthesis methods are extensively studied to prepare the uniform fine particles as these methods excel at controlling the composition and morphology of particles as mentioned above [4,5]. B. Aiken et al [6] and Kobayashi et al [7] prepared spherical monodispersed fine particles of a rare-earth monocomponent from a homogeneous solution by one of the liquid-phase methods.…”

Estudio de la formacion de los complejos intermedios durante la sintesis de alumina

“…La auto-hidrólisis de soluciones de sulfato de aluminio ha permitido obtener partículas esféricas monotamaño cuando se ejerce un fuerte control sobre la concentración del precursor, naturaleza de los aditivos y temperatura 4,5,9,10,11 . La lenta adición gota a gota, de NH4OH por ejemplo, a la solución de la sal de aluminio en continua agitación, también permite la obtención de partículas esféricas 18 . Si la adición de la base es rápida, las partículas que precipitan tienen una forma de aguja y si las soluciones de sulfato saturadas son evaporadas o enfriadas, las partículas adquieren una forma de cubos o plaquetas 19 .…”