On the structure of the active compound in mass deacidification of paper

Abstract Paper material produced after about 1850 contains additives that cause progressive acidification of the cellulose matrix, which can result in severe degradation of the material and simultaneous deterioration in its strength properties. This problem has affected whole stocks of libraries and archives, in response to which the process of “mass deacidification” has been developed. In this study, the structure and chemistry of the active reagent used in the main variant of this process has been identified as magnesium n-propoxycarbonate. The reagent, introduced in an inert fluorinated solvent, neutralizes acids in the paper matrix and simultaneously deposits a reserve of alkaline magnesium salts that counteract re-acidification. At the same time, it is much less alkaline than the magnesium alcoholates so that alkali-induced degradation reactions of cellulose (β-alkoxy elimination) are avoided.

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SEM Study of Tension Wood Fiber Morphology and its Effect on Paper Properties

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100079061 ◽

1977 ◽

Vol 35 ◽

pp. 308-309

Author(s):

K. W. Robinson

Keyword(s):

Tension Wood ◽

Wood Fiber ◽

Strength Properties ◽

Fiber Morphology ◽

Paper Properties ◽

Pure Cellulose ◽

Short Rotation ◽

Hardwood Trees ◽

Sem Study

Tension wood (TW) is an abnormal tissue of hardwood trees; although it has been isolated from most parts of the tree, it is frequently found on the upper side of branches and leaning stems. TW has been classically associated with geotropic alignment, but more recently it has been associated with fast growth. Paper made from TW is generally lower in strength properties. Consequently, the paper industries' growing dependence on fast growing, short- rotation trees will result in higher amounts of TW in the final product and a corresponding reduction in strength.Relatively few studies have dealt with the role of TW in the structure of paper. It was suggested that the lower strength properties of TW were due to a combination of factors, namely, its unique morphology, compression failures in the cell wall, and lower hemicellulose content. Central to the unique morphology of the TW fiber is the thick gelatinous layer (G-layer) composed almost entirely of pure cellulose.

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The Effect of Growth Rate on the Strength Properties of Sawn Beams of Silver Birch (Betula pendula Roth)

Scandinavian Journal of Forest Research ◽

10.1080/02827589950152250 ◽

1999 ◽

Vol 14 (1) ◽

pp. 18-26

Author(s):

R. A. Dunham ◽

A. D. Cameron ◽

J. A. Petty

Keyword(s):

Growth Rate ◽

Betula Pendula ◽

Strength Properties ◽

Silver Birch ◽

Betula Pendula Roth

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TLC-bioautography linked with guess: A truely targeted active compound isolation process

Planta Medica ◽

10.1055/s-0035-1556275 ◽

2015 ◽

Vol 81 (11) ◽

Cited By ~ 2

Author(s):

EM Grzelak ◽

Y Liu ◽

JW Nam ◽

JB Friesen ◽

SN Chen ◽

...

Keyword(s):

Active Compound ◽

Tlc Bioautography

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Hepatoprotective effects of Artemisia princeps and its active compound eupatilin against oxidative stress

Planta Medica ◽

10.1055/s-0036-1596458 ◽

2016 ◽

Vol 81 (S 01) ◽

pp. S1-S381

Author(s):

KH Jegal ◽

EH Jung ◽

SM Park ◽

IJ Cho ◽

SC Kim

Keyword(s):

Oxidative Stress ◽

Active Compound ◽

Artemisia Princeps ◽

Hepatoprotective Effects

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The Effect of Agents which Modify Platelet Behaviour and of Magnesium Ions on Thrombus Formation In Vivo

Thrombosis and Haemostasis ◽

10.1055/s-0038-1666898 ◽

1979 ◽

Vol 42 (02) ◽

pp. 603-610 ◽

Cited By ~ 59

Author(s):

J H Adams ◽

J R A Mitchell

Keyword(s):

Thrombus Formation ◽

Cerebral Arteries ◽

Magnesium Ions ◽

Body Formation ◽

Inflammatory Agent ◽

Platelet Thrombus ◽

Magnesium Salts ◽

Higher Doses ◽

Do So

SummaryThe ability of potential anti-thrombotic agents to modify platelet-thrombus formation in injured cerebral arteries in the rabbit was tested. Low doses of heparin were without effect, while higher doses produced variable suppression of white body formation but at the expense of bleeding. Aspirin did not inhibit white body formation but another non-steroid anti-inflammatory agent, flurbiprofen was able to do so, as was the anti-gout agent, sulphinpyrazone. Magnesium salts both topically and parenterally, suppressed thrombus formation and increased the concentration of ADP which was required to initiate thrombus production at minor injury sites.

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Modification of polymer matrix for carbon fiber reinforced plastic aimed at the increase of interfacial bond strength, deformation-strength properties and stability to thermal-oxidative destruction

Polymer materials and technologies ◽

10.32864/polymmattech-2017-3-4-19-36 ◽

2017 ◽

Vol 3 (4) ◽

pp. 19-36 ◽

Cited By ~ 1

Author(s):

V. I. Dubkova ◽

O. I. Maevskaya ◽

S. F. Zhandarov

Keyword(s):

Carbon Fiber ◽

Bond Strength ◽

Strength Properties ◽

Carbon Fiber Reinforced Plastic ◽

Oxidative Destruction ◽

Interfacial Bond ◽

Interfacial Bond Strength ◽

Fiber Reinforced Plastic ◽

Reinforced Plastic ◽

Thermal Oxidative Destruction

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Co-cooking nonwoods with hardwoods

TAPPI Journal ◽

10.32964/tj13.6.19 ◽

2014 ◽

Vol 13 (6) ◽

pp. 19-24

Author(s):

TROY RUNGE ◽

CHUNHUI ZHANG

Keyword(s):

High Performance Liquid Chromatography ◽

High Performance ◽

Paper Industry ◽

Pulp And Paper Industry ◽

Strength Properties ◽

Agricultural Residues ◽

Kraft Pulping ◽

Pulp And Paper ◽

Strength Increase ◽

Xylan Content

Agricultural residues and energy crops are promising resources that can be utilized in the pulp and paper industry. This study examines the potential of co-cooking nonwood materials with hardwoods as means to incorporate nonwood material into a paper furnish. Specifically, miscanthus, switchgrass, and corn stover were substituted for poplar hardwood chips in the amounts of 10 wt %, 20 wt %, and 30 wt %, and the blends were subjected to kraft pulping experiments. The pulps were then bleached with an OD(EP)D sequence and then refined and formed into handsheets to characterize their physical properties. Surprisingly, all three co-cooked pulps showed improved strength properties (up to 35%). Sugar measurement of the pulps by high-performance liquid chromatography suggested that the strength increase correlated with enriched xylan content.

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Chemical, anatomical, and technology aspects of Eucalyptus benthamii and Eucalyptus dunii for use in an integrated pulp and paper mill

TAPPI Journal ◽

10.32964/tj14.2.73 ◽

2015 ◽

Vol 14 (2) ◽

pp. 73-81 ◽

Cited By ~ 5

Author(s):

GISELY SAMISTRARO ◽

PETER W. HART ◽

JORGE LUIZ COLODETTE ◽

RICARDO PAIM

Keyword(s):

Energy Levels ◽

Black Liquor ◽

Basic Density ◽

Paper Mill ◽

Frost Tolerance ◽

Strength Properties ◽

Kappa Number ◽

Pulp Yield ◽

Chemical Compositions ◽

Physical Strength

Eucalyptus dunii has been commercially used in southern Brazil because of its relatively good frost tolerance and adequate productivity in the winter months. More recently, interest has grown in cultivating Eucalyptus benthamii Maiden & Cambage, which presents even superior frost tolerance compared to E. dunii and is highly productive as well. The quality of E. benthamii for pulp production is not yet proven. Thus, the chemical, anatomical, and technological aspects of pulp made from E. benthamii were compared with those of E. dunii for unbleached paper production. Samples of E. benthamii chips were obtained and analyzed for their basic density, chemical composition, higher heating value, trace elemental analysis, and chip size distribution. The chips were kraft cooked using conditions that produced a 74 ± 6 kappa number. The pulps were characterized for kappa number, yield, viscosity, and morphologic characteristics (e.g., length, wall thickness, and coarseness). Black liquor was analyzed for total solids, organics, inorganics, sodium sulfide, sodium hydroxide, and sodium carbonate. Brownstocks were beaten at five different energy levels in a Valley beater, and the physical strength properties of 120 g/m² handsheets were measured to develop a beater curve. The results of this study showed differences in delignification between the two woods and lower pulp yield for E. benthamii , which are related to their chemical compositions and basic densities. The E. benthamii studied in this work exhibited higher amounts of lignin and extractives, lower carbohydrate content, and lower basic density. However, cooking a blend of the two woods afforded good results in pulping and in physical pulp properties.

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Pilot trials of hemicelluloses extraction prior to thermomechanical pulp production: Part 1

TAPPI Journal ◽

10.32964/tj10.5.21 ◽

2011 ◽

Vol 10 (5) ◽

pp. 21-28 ◽

Cited By ~ 13

Author(s):

CARL HOUTMAN ◽

ERIC HORN

Keyword(s):

Oxalic Acid ◽

Energy Savings ◽

Wood Chip ◽

Strength Properties ◽

Thermomechanical Pulp ◽

Sugar Solution ◽

Bisulfite Treatment ◽

Pilot Trials ◽

Pulp Production ◽

Production Part

Pilot data indicate that wood chip pretreatment with oxalic acid reduced the specific energy required to make thermomechanical pulp. A combined oxalic acid/bisulfite treatment resulted in 21% refiner energy savings and 13% increase in brightness for aspen. A low level of oxalic acid treatment was effective for spruce. Energy savings of 30% was observed with no significant change in strength properties. Adding bisulfite did not significantly increase the brightness of the spruce pulp. For pine, the optimum treatment was a moderate level of oxalic acid, which resulted in 34% energy savings and an increase in strength properties. For all of these treatments 1–3 w/w % carbohydrates were recovered, which can be fermented to produce ethanol. The extract sugar solution contained significant quantities of arabinose.

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