Chilling group

Spinnerette Process. The basic spinning process is similar to the production of continuous filament yams and utilizes similar extmder conditions for a given polymer (17). Fibers are formed as the molten polymer exits the >100 tiny holes (ca 0.2 mm) of each spinnerette where it is quenched by chilled air. Because a key objective of the process is to produce a relatively wide (eg, 3 m) web, individual spinnerettes are placed side by side in order that sufficient fibers be generated across the width. This entire grouping of spinnerettes is often called a block or bank, and in commercial production it is common for two or more blocks to be used in tandem in order to increase the coverage and uniformity of laydown of the fibers in the web. 

Myoclonic Single and very brief jerks of all major muscle groups. Patients with these may not lose consciousness, due to the seizure lasting less than 3 to 4 seconds. Patients may describe these seizures as shoulder shrugs or spinal chills. Myoclonic seizures may cluster and build into a generalized tonic-clonic seizure. 

Selenium dusts produce respiratory tract irritation manifested by nasal discharge, loss of smell, epistaxis, and cough. A group of workers briefly exposed to unmeasured but high concentrations of selenium fume developed severe irritation of the eyes, nose, and throat, followed by headaches. Transient dyspnea occurred in one case. Workers exposed to an undetermined concentration of selenium oxide developed bronchospasm and dyspnea followed within 12 hours by metal fume fever (chills, fever, headache) and bronchitis, leading to pneumonitis in a few cases all were asymptomatic within a week. ... 

Similarly, very useful yields and diastereoselectivities were observed on alkylation of (5R)-2,3,5,6,-tetrahydro-5-phenyl-A-(ter/-butoxycarbonyl)-4/f-l,4-oxazin-2-one (7)92, The latter is available from (A)-phenylglycinol and phenyl 2-bromoacetate with subsequent protection of the amino group. The influence of the base, the counterion and the solvent was studied for this example. Sodium hexamethyldisilazanide in tetrahydrofuran/dimethoxyethane turned out to be by far the best conditions for deprotonation. Also, it seems to be essential that the base is added to the chilled solution of 7 and not vice versa. 

Adduct 5 has been isolated as the sodium salt in two different ways, i.e., either by solvent evaporation of the reaction mixture as obtained from equivalent amounts of the starting reagents in methanol solution,37,38 or by chilling a solution of 4-chIoro-3,5-dinitropyridine and sodium meth-oxide.15,49 The IR spectrum of the solid thus obtained shows a series of strong bands between 1040 and 1225 cm"1, which are typical of ketals, in agreement with the presence of a geminal dimethoxy grouping. The NMR spectrum... 

In some cases, another version of acid catalysis was used aqueous or alcoholic ammonia was added to a suspension of 2-benzopyryIium salt in alcohol, and after a few seconds, an excess of acetic acid was added to the mixture which was then heated to boiling. After chilling, isoquinolines 138 were obtained in good yield as free bases or salts. If the carbonyl group in intermediates 136 is electrophilic enough, and the hydrogen atom in position 4 is sufficiently mobile, the conversion of 2-benzopyrylium salts to isoquinolines occurs easily without acidic catalysis, for instance, in the case when this intermediate is 145 (75KGS25). 

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