SCALE OF WORK

Although apparatus employing ground-glass joints is excellent for work on a macro scale, it is not always suitable for very small-scale work as the joints are often disproportionately large compared with the rest of the assembly. The semi-micro apparatus described on pp. 59-72 can therefore be considered as being of general utility for this scale of work, especially as the use of corks has been reduced to a minimum. 

The size, however, should be commensurate with the size of the assetnblies and the scale of work. 

During preparation of the title compound from the imide and chlorine fluoride, initially at -111°C with slow warming dining 12 h to 0°C, the scale should be limited to 40 mmol or below. Forceful explosions occurred on several occasions when this scale was exceeded, but care is necessary on any scale of working. 

Cyanoethylation of 1,2,3,4-tetrahydrocarbazole initiated by the quaternary base had been effected smoothly on twice a published scale of working. During a further fourfold increase in scale, the initiator was added at 0°C, and shortly after cooling had been stopped and heating begun, the mixture exploded. A smaller proportion of initiator and very slow warming to effect reaction are recommended (to avoid rapid polymerisation of the nitrile by the base). 

The title compound is produced by treatment of 2-iodylbenzoic acid with acetic anhydride in acetic acid, and has found wide application as a mild oxidant ( Dess-Martin periodinane ) for ly and 2y alcohols. Although it appears not to be sensitive to impact, unlike the precursor acid, both explode violently when heated under confinement. The oxidant, on treatment with water is hydrolysed back to the explosive 2-iodylbenzoic acid. Forethought and caution are advised before using these explosive materials on any scale of working. 

Interaction of a mixture of sulfur and the oxide under inert atmosphere above 160°C to form tetraphosphorus hexaoxide tetrasulfide is violent and dangerous on scales of working other than small [1], A safer procedure involving distillation of phosphorus(V) oxide and phosphorus(V) sulfide is described [2],... 

Most studies of micellar effects upon rates or products of organic reactions have been made with very low concentrations of reactants, and this small scale of work is not very encouraging for the synthetic organic chemist. An additional disadvantage is that surfactants complicate product separation by extraction or distillation, and to date most studies in this general area have been exploratory and have been aimed at solving these problems. 

Molybdenum and tungsten atoms seem to react with alkylbenzenes more efficiently than chromium atoms yields of 30 to 50% are reported (113). Conventional routes to the synthesis of tungsten-arene complexes are difficult and inefficient so that the ability to prepare these compounds in high yield via tungsten atoms is of special significance. Unfortunately, tungsten has a very high vaporization temperature and the scale of work with its vapor is necessarily limited. 

Safe storage of chemicals, 367 Safety literature, 368 Samarium(ii) complexes on silica, 368 Sample dissolution, 369 Scale of work, 369... 

The scale of work ranges from hundred-gram to kilogram quantities of combined fission products, rare earths, americium,... 

When performing an analysis of the sample, the choice of method will be influenced by the quantity of sample available. The following terms refer to scale of working macro, semi-micro, micro and ultra-micro. 

The authors feel that it is also important to briefly mention the source of the TFE cylinders in the DesMarteau facility, especially since one can no longer readily purchase TFE from the fluorochemical industry for the scale of work done or to be done in the facilities described herein. The current solution for obtaining the quantities of TFE required for ongoing research will be discussed under the section on the second-generation TFE facility, where this information is more pertinent. The initial cylinders of TFE in the first-generation TFE facility at Clemson came from the Bayonne, New Jersey plant of Imperial Chemical Industries PEC (ICI). In 1999, Asahi Glass Co., Ltd. purchased this plant, and in 2007 a decision was made to... 

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