Temperature hydrolysis and

Alkylated aromatics have excellent low temperature fluidity and low pour points. The viscosity indexes are lower than most mineral oils. These materials are less volatile than comparably viscous mineral oils, and more stable to high temperatures, hydrolysis, and nuclear radiation. Oxidation stabihty depends strongly on the stmcture of the alkyl groups (10). However it is difficult to incorporate inhibitors and the lubrication properties of specific stmctures maybe poor. The alkylated aromatics also are compatible with mineral oils and systems designed for mineral oils (see Benzene Toulene Xylenes and ethylbenzene). ... 

The formation of oxide compounds as a result of the thermal treatment of oxyfluorides is due to high temperature hydrolysis and reduction-oxidation processes. 

Many approaches have been taken to prepare colloidal doped semiconductor nanocrystals. For example, hot-injection methods have been used to synthesize colloidal Mn2+-doped CdSe (47, 48), ZnSe (49), and PbSe (50) colloidal nanocrystals. Colloidal ZnO DMS-QDs doped with Co2+, Ni2+, and Mn2+ have been prepared by low-temperature hydrolysis and condensation (51-54). Sol-gel methods have been used to prepare colloidal doped TiC>2 (55-57) and Sn02 (58-62) nanocrystals. Inverted micelle methods have been used for preparation of a range of doped II-VI sulfide DMS-QDs at low temperatures (63-68). A high-temperature lyothermal single-source method was used to synthesize Co2+- and Eu3+-doped CdSe nanocrystals (69, 70). Autoclaving has occasionally been used to induce crystallization at lower temperatures than reached under atmospheric pressures while retaining colloidal properties, for... 

When selecting polyurethanes for any application, a full understanding of the working conditions should be obtained to prevent overspecifying the grade and type. These conditions may include the interaction of temperature, hydrolysis, and wear in a dynamic situation. The limitations of polyurethanes also must be taken into account and some redesign carried out if needed. 

Many arylated cyclohexanone and 1,3-cyclohexadione derivatives are synthesized through aldol condensations, in many cases in combination with Michael additions. Some examples are given below Petrows ketone98 via bromination at low temperature, hydrolysis and decarboxylation gives 3,5-diphenylphenol... 

When a tetraethoxysilane-water-hydrochloric add-alcohol solution of appropriate composition is held at near room temperature, hydrolysis and polycondensation occur and the solution viscosity increases. Fibers can be drawn at a viscosity about 10 Pa s, which occurs during the course of sol to gel transition. It should be pointed out that for an alkoxide solution to be spinnable (Sakka,... 

Rybkin and Nesterenko used the same experimental routine to investigate the processes of high-temperature hydrolysis and oxidation of solid and fused sodium iodide [256,257], According to the authors estimation, the enthalpies of the following reactions... 

An evident disadvantage of the above method is assumption that the partial pressure of HCl in the gas phase is equal to the equilibrium pressure. The same method was used to study the high-temperature hydrolysis and oxidation of sodium iodide.According to the estimates, the heats of the reactions ... 

The development of the science and technology of sol-gel processes has had a strong technological impact on research into coatings, since ceramic and vitreous mata-ials can be obtained from colloid suspensions, or through low temperature hydrolysis and polymerization of organic-metal compounds. 

Acid amides have weakly amphoteric properties, and thus give salts such as CjHsCONHj.HCl with strong acids, and salts of the type C HsCONHNa with strong bases. These compounds have to be prepared at low temperatures to avoid hydrolysis, and are difficult to isolate. The mercury derivatives can, however, usually be readily prepared, because mercuric oxide is too feebly basic to cause hydrolysis of the amide, and the heavy mercuric derivatives crystallise well. 

The hydrolysis of urea is strongly temperature-dependent, with the rate being negligible at room temperature. The rate of hydrolysis, and thus the rate of precipitate formation, can be controlled by adjusting the solution s temperature. Precipitates of BaCr04, for example, have been produced in this manner. 

Chemical Properties. The hydrolysis of PET is acid- or base-catalyzed and is highly temperature dependent and relatively rapid at polymer melt temperatures. Treatment for several weeks in 70°C water results in no significant fiber strength loss. However, at 100°C, approximately 20% of the PET tenacity is lost in one week and about 60% is lost in three weeks (47). In general, the hydrolysis and chemical resistance of copolyester materials is less than that for PET and depends on both the type and amount of comonomer. 

Waste treatment of fluoroborate solutions includes a pretreatment with aluminum sulfate to facditate hydrolysis, and final precipitation of fluoride with lime (18). The aluminum sulfate treatment can be avoided by hydrolyzing the fluoroborates at pH 2 in the presence of calcium chloride at this pH, hydrolysis is most rapid at elevated temperature (19). 

Rhenium hexafluoride [10049-17-9J, ReF, is a pale yeUow soHd at 0°C, but a Hquid at ambient temperature. In the presence of moisture it hydroly2es rapidly forming HF, Re02, and HRe04 (see Rheniumand rhenium compounds). It is not safe to store ReF in a glass trap or glass-lined container. Leaks in the system can initiate hydrolysis and produce HF. The pressure buildup causes the system to burst and an explosion may result. 

Plasteins ate formed from soy protein hydrolysates with a variety of microbial proteases (149). Preferred conditions for hydrolysis and synthesis ate obtained with an enzyme-to-substrate ratio of 1 100, and a temperature of 37°C for 24—72 h. A substrate concentration of 30 wt %, 80% hydrolyzed, gives an 80% net yield of plastein from the synthesis reaction. However, these results ate based on a 1% protein solution used in the hydrolysis step this would be too low for an economical process (see Microbial transformations). 

Some unsaturated ketones derived from acetone can undergo base- or acid-catalyzed exothermic thermal decomposition at temperatures under 200°C. Experiments conducted under adiabatic conditions (2) indicate that mesityl oxide decomposes at 96°C in the presence of 5 wt % of aqueous sodium hydroxide (20%), and that phorone undergoes decomposition at 180°C in the presence of 1000 ppm iron. The decomposition products from these reactions are endothermic hydrolysis and cleavage back to acetone, and exothermic aldol reactions to heavy residues. 

Only Pu(III) oxyhahdes (PuOF, PuOCl, PuOBr, and PuOI) and Pu(VI) oxyhaHdes (PUO2F2, PuOF, and PUO2CI2 6H20) are known. Of these the most important are PuOCl, which is the stable product of hydrolysis of PUCI3 (s) with H2O (g) (157), and PUO2F2, which is the product of low temperature hydrolysis of PuF and one of the products of room temperature hydrolysis of PuF (158—160). 

Hydrolysis of primary amides cataly2ed by acids or bases is very slow. Even more difficult is the hydrolysis of substituted amides. The dehydration of amides which produces nitriles is of great commercial value (8). Amides can also be reduced to primary and secondary amines using copper chromite catalyst (9) or metallic hydrides (10). The generally unreactive nature of amides makes them attractive for many appHcations where harsh conditions exist, such as high temperature, pressure, and physical shear. 

Hydrolysis of solutions of Ti(IV) salts leads to precipitation of a hydrated titanium dioxide. The composition and properties of this product depend critically on the precipitation conditions, including the reactant concentration, temperature, pH, and choice of the salt (46—49). At room temperature, a voluminous and gelatinous precipitate forms. This has been referred to as orthotitanic acid [20338-08-3] and has been represented by the nominal formula Ti02 2H20 (Ti(OH). The gelatinous precipitate either redissolves or peptizes to a colloidal suspension ia dilute hydrochloric or nitric acids. If the suspension is boiled, or if precipitation is from hot solutions, a less-hydrated oxide forms. This has been referred to as metatitanic acid [12026-28-7] nominal formula Ti02 H2O (TiO(OH)2). The latter precipitate is more difficult to dissolve ia acid and is only soluble ia concentrated sulfuric acid or hydrofluoric acid. 

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