Adaptation of the P. E. Model 295 spectrophotometer to constant-temperature measurements

The Fock test is widely used for assessing the reactivity of dissolving pulp. The objective of this study was to modify the method to improve the repeatability of the test. Various parameters that affect the repeatability of the Fock test were investigated. The results showed that Fock reactivity is dependent on testing conditions affecting the xanthation between cellulose and carbon disulfide, such as the moisture content of the pulp sample, sodium hydroxide (NaOH) concentration, xanthation temperature, carbon disulfide dosage, and xanthation time. The repeatability of the test was significantly improved using the following modified testing procedure: air dried sample in the constant temperature/humidity room, xanthation temperature of 66°F (19°C) in a water bath, xanthation time of 3 h, NaOH concentration of 9% (w/w), and 1.3 mL carbon disulfide.

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Use of distributed sensors for sea temperature measurements

10.33075/978-5-6040795-4-6 ◽

2018 ◽

Author(s):

V.A. Gayskiy ◽

◽

P.V. Gayskiy ◽

Keyword(s):

Temperature Measurements ◽

Sea Temperature ◽

Distributed Sensors

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ACTION OF ENZYME DIGESTED PITUITARY GLANDS OF THE SKIPPER-FROG ON THE OVULATION OF THE SAME

Acta Endocrinologica ◽

10.1530/acta.0.xxxiii0255 ◽

1960 ◽

Vol XXXIII (II) ◽

pp. 255-260 ◽

Cited By ~ 3

Author(s):

L. S. Ramaswami ◽

A. B. Lakshman

Keyword(s):

Pituitary Gland ◽

Constant Temperature ◽

Constant Temperature Bath ◽

Predominant Role ◽

Lower Vertebrates ◽

Pituitary Glands ◽

Stimulating Factor

ABSTRACT By using enzymes, the gonadotrophic factors in the skipper-frog pituitary glands have been selectively inactivated or destroyed. By incubating a known number of pituitary gland homogenate with ptyalin in a constant temperature bath for 5–6 h the follicle-stimulating factor is inactivated; with trypsin or pepsin, the luteinizing factor is inactivated. Bioassay on gravid skipper-frogs indicate that the ptyalin digested homogenate brings about profuse spawning while the trypsin or pepsin digested homogenates do not. When a combination of ptyalin digested and trypsin digested homogenates is injected into fresh gravid skipper-frogs, poor spawning is brought about. These experiments show that the luteinizing factor alone brings about more profuse spawning than when it is combined with the follicle-stimulating factor. It is likely, therefore, that in the lower vertebrates the luteinizing factor of the pituitary gland plays a more predominant role. The exact proportions in which the different dosages for the control and test animals are administered are also tabulated.

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