Modifying the composition of wood during hydrothermal treatment

Wood is a product of plant origin having complex element and component composition. Under the influence of temperature in the presence of moisture lignocarbohydrate complex decomposes and extraction of water soluble substances takes place. Aqueous distillate contains a large number of different chemicals, the most dangerous of which are furfural and formaldehyde. The intensity of the process of extraction in the wood depends on the temperature. The formation of these substances is observed even at low temperatures around 60-70 º C and long duration of exposure, which is characteristic of conditions during chamber wood drying.

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The component composition of planted pine wood cultivated in the boreal zone

Nordic Pulp & Paper Research Journal ◽

10.1515/npprj-2020-0058 ◽

2020 ◽

Vol 35 (4) ◽

pp. 685-693

Author(s):

D. A. Danilov ◽

A. V. Griazkin ◽

V. A. Sokolova ◽

I. V. Bacherikov

Keyword(s):

Component Composition ◽

Water Soluble ◽

Boreal Zone ◽

Lower Content ◽

Average Yield ◽

Leningrad Oblast ◽

Pine Wood ◽

Natural Stands

AbstractThe present study analyzes the composition of pine wood cultivated on artificial plantations in the Leningrad Oblast (Region). Comparing to pine wood from natural stands, a smaller heartwood zone along the height of the pine trunk and a lower content of resinous substances are noted. The content of cellulose and lignin in the heartwood and sapwood of pine is distributed differently along the trunk. The distribution of pentosans and water-soluble substances in the heartwood and sapwood along the trunk is associated with the lignin complex. The component composition of the studied pine wood from planted stands is quite uniform in its indicators if compared to the wood of older natural stands. Sulphate pulping of planted pine wood showed a higher yield of technical cellulose than the average yield from wood obtained at natural stands of the studied region.

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Optical Transitions in Chalcogenide Glasses From the Point of View of a Barrier-Cluster Model

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.39-40.253 ◽

2008 ◽

Vol 39-40 ◽

pp. 253-256

Author(s):

Ivan Baník

Keyword(s):

Optical Absorption ◽

Low Temperatures ◽

Cluster Model ◽

Chalcogenide Glasses ◽

Temperature Shift ◽

Point Of View ◽

Optical Transitions ◽

Influence Of Temperature ◽

Exponential Tails ◽

Influence Of Temperature On

A barrier-cluster model of chalcogenide glasses is employed to analyze optical transitions near the absorption edge. The influence of temperature on the optical absorption is studied. The model is used to explain the temperature shift of exponential tails of the optical absorption and the temperature dependence of the optical forbidden-band width at low temperatures.

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Influence of temperature processing on the constitutive and inducible resistance of rye seedlings to chloride salinization

Вестник Пермского университета. Серия «Биология»=Bulletin of Perm University. Biology ◽

10.17072/1994-9952-2021-2-134-140 ◽

2021 ◽

pp. 134-140

Author(s):

L. A. Chudinova ◽

◽

D. R. Yusupov ◽

Keyword(s):

Growth Rate ◽

Sodium Chloride ◽

Protective Effect ◽

Soluble Proteins ◽

Final Concentration ◽

Water Soluble ◽

Thermal Pretreatment ◽

Thermal Hardening ◽

Influence Of Temperature ◽

Inducible Synthesis

We studied the growth rate of rye seedlings, as well as the dynamics of the content of soluble proteins and proline in the shoots during their adaptation to sharp (300 mM NaCl once, exposure time 9 days) and gradual (100 mM NaCl, then 100 mM NaCl after 2 days to the final concentration of 400 mM) salinity with sodium chloride in the presence or absence of thermal hardening (+40°C, 3 h). The established dy-namics of the content of proline and soluble proteins in the shoots suggests that the formation of re-sistance to salinity is determined by the high constitutive level of proline, as well as the stress-inducible synthesis of proline and water-soluble proteins. Thermal pretreatment of the seedlings stimulated their constitutive stability to a greater extent. The detected metabolic changes are obviously related to one of the possible mechanisms of the protective effect of thermal hardening on subsequent salinization.

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The influence of temperature on the succession of redial and cercarial generations of Fasciola gigantica in a snail host

Parasitology ◽

10.1017/s0031182000074321 ◽

1964 ◽

Vol 54 (1) ◽

pp. 59-65 ◽

Cited By ~ 27

Author(s):

J. A. Dinnik ◽

N. N. Diknik

Keyword(s):

Larval Development ◽

Low Temperatures ◽

First Generation ◽

Cold Season ◽

Snail Host ◽

Fasciola Gigantica ◽

Natural Conditions ◽

Influence Of Temperature ◽

Cercarial Production ◽

Influence Of Temperature On

Experiments on the larval development of Fasciola gigantica carried out under natural conditions have shown that at temperatures of 16° C. or less the rediae did not produce cercariae. The first-generation rediae, developed from the sporocyst, and all the rediae of subsequent generations produced only daughter rediae and did not change over to the production of cercariae as long as the low temperatures of the cold season lasted.As soon as the cold season ended and the temperature of the water in the aquaria containing the infected snails rose to a mean maximum of 20° C. all the rediae switched from redial to cercarial production.

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Influence of Temperature on Performance in Guinea Pigs

American Journal of Physiology-Legacy Content ◽

10.1152/ajplegacy.1957.190.3.457 ◽

1957 ◽

Vol 190 (3) ◽

pp. 457-458 ◽

Cited By ~ 7

Author(s):

Charles G. Wilber

Keyword(s):

Low Temperatures ◽

Guinea Pigs ◽

Peak Performance ◽

Albino Rats ◽

Small Animals ◽

Influence Of Temperature ◽

Influence Of Temperature On ◽

Endocrine Factors ◽

The Difference ◽

Large Animals

Guinea pigs were forced to swim to total exhaustion in water at various temperatures. Small animals (400 gm) showed peak performance at about 40°C, large ones (1000 gm) at about 35°C. Large animals swam longer at low temperatures but shorter at high temperatures than did small ones. At 35°C all guinea pigs swam for an average of about 150 minutes. In general this species shows much less capacity for swimming than do albino rats. The difference may be related to diet or to endocrine factors.

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Hydroid Pigments. I. General discussion and pigments of the Sertulariidæ

Journal of the Marine Biological Association of the United Kingdom ◽

10.1017/s0025315400051948 ◽

1931 ◽

Vol 17 (3) ◽

pp. 739-749 ◽

Cited By ~ 5

Author(s):

Nellie M. Payne

Keyword(s):

Water Soluble ◽

Plant Origin ◽

Plant Kingdom ◽

Flavone Derivative

1. The yellow colours of the hydroids include at least two groups, the carotinoids found in the Antennulariidæ and Haliciidæ and the flavone-like pigments that occur in the Sertulariidæ. From the literature a third group, the uradines, may be added.2. The flavone pigments and their relatives are all water soluble and are thus distinguished from the carotinoids which are not water soluble, but may be dissolved in the usual fat solvents.3. In the Sertulariidæ studied, a graded series of chromatophore groups and pigments was found which ranged from the colourless species Sertularia argentea Ellis and Solander, through the yellow of Sertularella gayi Lamaroux and S. polyzonias Linnæus, to the orange-brown of Thuiaria articulata Pallas. The brown of Sertularia pumila is probably also a flavone derivative.4. The flavones and related pigments occur extensively in the plant kingdom. It is probable that the flavone-like pigments found in the Sertulariidæ are of plant origin.

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THE INFLUENCE OF TEMPERATURE ON THE ACTION OF STRYCHNIN IN FROGS

Journal of Experimental Medicine ◽

10.1084/jem.18.3.300 ◽

1913 ◽

Vol 18 (3) ◽

pp. 300-309 ◽

Cited By ~ 2

Author(s):

Thomas Stotesbury Githens

Keyword(s):

Low Temperature ◽

High Temperatures ◽

Low Temperatures ◽

Room Temperature ◽

Drug Action ◽

The State ◽

Great Caution ◽

Influence Of Temperature ◽

Influence Of Temperature On

In order to establish the influence of temperature upon the effect of varying doses of strychnin injected into frogs, the animals must be kept under observation for several days and at various definite degrees of temperature. Statements that the animal was kept "cold," "at room temperature," or "warm" are insufficient. With a certain dose tetanus may result constantly at 30° C. yet never appear at 21° C., and either of these temperatures might be described as warm, when compared to a room temperature of 15° C. Furthermore an animal may apparently fail to respond in the cold to an injection of certain doses of strychnin and yet be found in tetanic convulsions the next day. That an animal may have late, long lasting, or strong tetanus while kept at such a low temperature as 5° C. after an injection of a dose of strychnin smaller than 0.01 of a milligram per frog emphasizes the fact that great caution must be exercised in formulating laws as to the influence of temperature on drug action. The main results of this investigation may be summarized as follows: Doses of strychnin amounting to 0.0006 of a milligram per gram of frog will cause tetanus at all temperatures between 5° C. and 30° C., although at low temperatures the tetanus may appear late. A dose of 0.0003 of a milligram per gram of frog will frequently produce tetanus at 5° C. as well as at 30° or 27° C., but may nevertheless fail to produce any reaction at such an intermediary temperature as 21° C. Smaller doses, 0.0002 of a milligram per gram, will cause tetanus in the cold but not at high temperatures. It may be stated in general that in frogs kept at low temperatures the tetanic state sets in later, continues longer, and each tetanic attack is of longer duration, while in the interval between the attacks the state of tonus is higher and the animals are more irritable than when they are kept at higher temperatures.

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