Warming

The diazoamino-compounds are usually yellow in colour, and do not dissolve in acid they can usually be isolated and crystallized without decomposition. When treated with HNO2 two molecules of diazonium salt are formed. Form an azo compound when warmed with an amine and its hydrochloride, e.g. 

The diazonium salts usually decompose when warmed with water to give a phenol and nitrogen. When treated with CuCl, CuBr, KI, the diazo group is replaced by chlorine, bromine or iodine respectively (Sandmeyer reaction). A diazonium sulphate and hydroxyl-amine give an azoimide. The diazonium salt of anthranilic acid (2-aminobenzoic acid) decomposes to give benzyne. ... 

HC CH(0H) CH20H. optically active. D-glyceraldehyde is a colourless syrup. May be prepared by mild oxidation of glycerol or by hydrolysis of glyceraldehyde acetal (prepared by oxidation of acrolein acetol). DL-glyceraldehyde forms colourless dimers, m.p. IBS-S C. Converted to methylglyoxal by warm dilute sulphuric acid. The enantiomers... 

Current requirements for vehicles are more pronounced for warm conditions than for cold for many reasons e.g., improved aerodynamics, transversal placement of the motor, generally higher temperatures under the hood, such that the automobile manufacturers prefer a reduction, rather than increase in RVP. 

The 15W40 or 15W50 oils are the most widespread in temperate climates (Western Europe), while the 20W40 or 20W50 oils are used in relatively warm climates (Mediterranean countries. Middle East, South America). The 5W or lOW grades are used in countries having severe winters such as Scandinavia and Canada. 

For example, the many deepwater fields located in the Gulf of Mexico are of Tertiary age and are comprised of complex sand bodies which were deposited in a deepwater turbidite sequence. The BP Prudhoe Bay sandstone reservoir in Alaska is of Triassic/ Cretaceous age and was deposited by a large shallow water fluvial-alluvial fan delta system. The Saudi Arabian Ghawar limestone reservoir is of Jurassic age and was deposited in a warm, shallow marine sea. Although these reservoirs were deposited in very different depositional environments they all contain producible accumulations of hydrocarbons, though the fraction of recoverable oil varies. In fact, these three fields are some of the largest in the world, containing over 12 billion barrels of oil each ... 

Due to the absorbed photon energy in the moment of the beam admission the particles and the substrate surface warm up very fast. As a consquence of the thermal induced stresses between the relative brittle hard particles, some particles brake apart and, because of the released impulse energy, they are ejected out of the effective beam zone, transmission... 

The changes described above also allowed much easier access to the high voltage cable for routine (6-month) owner directed, service operations, and provided better upper and lower x-ray cabinet and control cabinet ventilation. With the exception of the x-ray tubes, all the individual manufactured components, on all four systems are identical. There are very subtle differences in the warm-up/start-up sequence on the x-ray controllers on the newer systems due to model/year and x-ray tube differences. The last three systems were supplied with environmental type key-boards for the image processors and base-mounted , rather than conduit-mounted exterior warning indicators. The first system was subsequently upgraded to include the better keyboard and the external warning appliances/features. 

These systems have been operated in extremely low quality (and radioactivity contaminated) industrial environments for the past several years without any major equipment or component failures. Utilizing specialized operating/warm-up procedures, they have operated in low grade, out-of-doors, dust ridden, rain-soaked, industrial environments at temperature ranges which greatly exceed the original equipment manufacturers (OEM) specified limits. The systems have been successfully operated at ambient temperatures of minus 10 to plus 103 degrees Fahrenheit without any pre-mature or un-anticipated equipment failures. 

An interesting experimental technique is heat development of nuclei. The liquid is held at the desired temperature for a prescribed time, while nuclei accumulate they are then made visible as crystallites by quickly warming the solution to a temperature just below Tq, where no new nuclei form but existing ones grow rapidly. 

Clausius R 1857 Uber die Art von Bewegegung, die wir Warme nennen Ann. Phys. Chem. 100 353... 

Thus under standard conditions chloride ions are not oxidised to chlorine by dichromate(Vr) ions. However, it is necessary to emphasise that changes in the concentration of the dichromate(VI) and chloride ions alters their redox potentials as indicated by the Nernst equation. Hence, when concentrated hydrochloric acid is added to solid potassium dichromate and the mixture warmed, chlorine is liberated. 

Again, nitric acid readily dissolves lead but is unable to oxidise lead beyond the oxidation state -P 2. The reduction products of the nitric acid vary with the concentration of acid used, and a number of nitrogen oxides are usually obtained. Warm dilute nitric acid gives mainly nitrogen oxide, NO. 

Carbon monoxide is formed by the incomplete combustion of carbon. It is prepared in the laboratory by dropping methanoic (formic) acid into warm concentrated sulphuric acid the latter dehydrates the methanoic acid ... 

Concentrated sulphuric acid and nitric acid—powerful oxidising agents—attack all the elements except nitrogen, particularly when the acids are warm. The products obtained reflect changes in stability of the oxidation states V and III of the Group V elements. 

The head element nitrogen does not react. White phosphorus, however, reacts when warmed with a concentrated solution of a strong alkali to form phosphine, a reaction which can be regarded as a disproportionation reaction of phosphorus ... 

The reduction of a nitrate, for example potassium nitrate, by iron(ll) sulphate in the presence of concentrated sulphuric acid gives reasonably pure nitrogen monoxide. The mixture is warmed and at this temperature the nitrogen monoxide produced does not combine with uncharged iron(II) sulphate (see below). 

In concentrated nitrie acid (when warmed) the reaction is ... 

The gas is washed with water to remove any hydrogen chloride. Since iron(II) sulphide is a non-stoichiometric compound and always contains some free iron, the hydrogen sulphide always contains some hydrogen, liberated by the action of the iron on the acid. A sample of hydrogen sulphide of better purity can be obtained if antimony(III) sulphide, (stibnite) SbjSj, is warmed with concentrated hydrochloric acid ... 

Alternatively a mixture of almost any solid chloride and manganese-(IV) oxide will yield chlorine when warmed with concentrated sulphuric acid. These are the most common laboratory methods but there are many others. 

It is prepared in the laboratory by warming sodium chloride with concentrated sulphuric acid ... 

The stability of the halate(I) ion decreases, as expected, from C10 to 10 and only the chlorate(I) ion can be considered reasonably stable even in aqueous solution. Solid sodium bromate(I). NaBrO (with five or seven molecules of water of crystallisation) can be obtained, but on standing or warming it disproportionates ... 

Warm concentrated H2SO4 on the dry solid HF evolved HCl evolved HBr. SO 2 and Bt2 evolved SO2, H2S. and I2 evolved... 

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