Rate of Threading a Cellulose Chain into the Binding Tunnel of a Cellulase

During an anatomical study of the jute and hemp plants carried out by one of us (B. C. K.), the opportunity was taken of reinvestigating in these plants the structure of the walls of the fibres, using the term “fibre” in its botanical sense. The so-called “bast” fibres are of particular interest in wall studies since it was apparently on the basis of their investigation that the “crossed fibrillar” conception was first introduction. Thus we find Reimers (1922) stating that in a number of plants, including hemp, the walls of these fibres are composed of two or more layers differing considerably in cellulose-Chain direction. Since that time numerous other statement of this kind have been made for different types of cell (Freudenberg and Dürr 1932; Ritter 1930; Ritter and Chidester 1928; Bailey and Kerr 1935); v. Iterson 1937; Wuhrmann-Meyer 1939). It seems rather a common feature of the evidence quoted in support of such a structure that it is derived from material swollen considerably either in acid or alkali. Certainly the optical properties of the wall have been used in support (Freudenberg and Durr 1932; Bailey and Kerr 1935 v. Iterson 1937; Wuhrmann-Meyer 1939). It seems rather a common feature of the evidence quoted in support of such a structure that it is derived from material swollen considerably either in acid or alkali. Certainly the optical properties of the wall have been used in support (Freudenberg and Durr 1932; Bailey and Kerr 1935 v. Iterson 1937; Wuhrmann-Meyer 1939). It seems rather a common feature of the evidence quoted in support of such a structure that it is derived from material swollen considerably either in acid or alkali. Certainly the optical properties of the wall have been used in support (Freudenberg and Durr 1932; Bailey and Kerr 1935; v. Iterson 1937; Wuhrmann-Meyer 1939). It seems rather a common feature of the evidence quoted in support of such a structure that it is derived from material swollen considerably either in acid or alkali. Certainly the optical properties of the wall have been used in support (Freudenberg and Dürr 1932; Bailey and Kerr 1935) but the implication of such work have already been discussed elsewhere (Preston 1939 a ). We are here concerned chiefly with the swelling technique. While it is not to be suggested that treatment with swelling reagents totally invalidates all observations of this type, it is quite clear that in some cases at least observation of swollen material can give an entirely erroneous conception of the wall in its natural condition. This is perhaps particularly clear in the case of jute, for which Osborne (1935, quoted also by Barker 1938) refers to the fibres as being composed of a series of chains lying at a considerable angle to the longitudinal axis of the cell, in spite of contrary X-ray evidence.

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Moist Heat Accelerated Aging Test of Naturally Aged Paper by Suspension Method

Restaurator International Journal for the Preservation of Library and Archival Material ◽

10.1515/res-2013-0006 ◽

2013 ◽

Vol 34 (2) ◽

Cited By ~ 1

Author(s):

Kang Lee ◽

Masamitsu Inaba

Keyword(s):

Degradation Rate ◽

Accelerated Aging ◽

Accelerated Ageing ◽

Natural Ageing ◽

Cellulose Chain ◽

Accelerated Aging Test ◽

Tear Index ◽

Aging Test ◽

Degradation Rate Constant ◽

Physical And Chemical

AbstractThis research was planned to clarify the relationship between natural ageing and accelerated ageing of paper using naturally aged paper. First, samples of paper which had deteriorated over time for 130 to 80 years were artificially aged at 80°C, 65% RH, and their physical and chemical changes were investigated. Oxalic acid contained in the samples before accelerated ageing increased, while glycolic acid showed a tendency to decrease. This means that accelerated ageing test did not simulate the chemical processes occurring during natural ageing in a straight forward manner. On the other hand, paper in which many organic acids had accumulated by natural ageing showed larger degradation rate indicators of tear index and burst index i.e. initial degradation rate constant divided by initial tear index or initial burst index before accelerated ageing and discolouration rate. That of values of the degradation rate indicators of tear index and burst index and the discolouration rate showed good correlation with the number of cellulose chain breaks. However, the number of cellulose chain breaks is not simply correlated with the concentration of hydrogen ion which is an index of the acidic hydrolysis of paper. Oxidation contributes to the rate of cellulose chain breaks.

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Silvicultura do eucalipto e a especialização do trabalho na cadeia produtiva de papel e celulose em Imperatriz-MA

GeoTextos ◽

10.9771/geo.v15i2.32131 ◽

2019 ◽

Vol 15 (2) ◽

Author(s):

Allison Bezerra Oliveira ◽

Maria Da Conceição Mesquita Leal

Keyword(s):

Field Research ◽

Secondary Data ◽

Cellulose Chain ◽

Production Chain ◽

Technical Schools ◽

Technical Requirements ◽

Professional Workers ◽

Local Plant ◽

Labor Specialization ◽

The City

O presente trabalho tem por objetivo analisar o processo de especialização produtiva do trabalho no Maranhão mediante o avanço da cadeia de papel e celulose em face da expansão e da intensificação da silvicultura do eucalipto desencadeada pela implantação da unidade fabril da Suzano Papel e Celulose no município de Imperatriz, sudoeste do estado do Maranhão. Dessa forma, busca-se questionar: há em curso uma especialização produtiva do trabalho nesse segmento, considerando trabalhadores com qualificação profissional de nível médio/técnico, em Imperatriz? Metodologicamente, além de revisão da literatura pertinente, utilizou-se, conjuntamente com pesquisas de campo, dados secundários sobre transformações no emprego local e nas qualificações profissionais locais advindas da implantação da Suzano. Os dados utilizados são originários da RAIS; CAGED; IBGE, além de escolas técnicas locais. Os resultados encontrados permitiram realizar mapeamento da cadeia de trabalho no segmento em destaque e verificar que há intenso e rápido aprofundamento da especialização produtiva do trabalho no setor de papel e celulose no estado. Abstract EUCALYPTUS SILVICULTURE AND THE SPECIALIZATION OF WORK IN THE PULP AND PAPER PRODUCTION CHAIN IN IMPERATRIZ - MA The main goal of this article is to study the labor specialization process in the state of Maranhão through the progress if the paper and cellulose chain over the expansion and reinforcement of the forestry from eucalyptus based on the implementation of the factory “Suzano Papel e Celulose” in Imperatriz, southwest of the Maranhão State. This drives the question: is there a movement to improve and specialize workers in this sector, taking into consideration not specialized or technical workers in the city of Imperatriz? For methodology it was used the book references, field research and secondary data about the changes in the way of work in the local plant and technical requirements for professional workers due to the implementation of “Suzano Papel e Celulose”. The data comes from “RAIS”; “CAGED”; “IBGE” and local technical schools. The results allow us to map the working group in the sector emphasizing that there is an intense and quick specialization regarding the work in this specific sector of paper and cellulose.

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