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Full-Text Articles in Life Sciences

Alternate Models Of Centrifugal Cleaners For The Paper Industry, Eric Bauer Dec 2000

Alternate Models Of Centrifugal Cleaners For The Paper Industry, Eric Bauer

Paper Engineering Senior Theses

Clean pulp is essential to the optimum operation of any paper machine. The hydrocyclone is the most space, energy and cost efficient method to remove both heavy and light contaminants from a papermaking slurry. The efficiency of a hydrocyclone cleaner increases as the amount of removed contaminants increases. An efficient hydrocyclone allows the least amount of usable fiber to be lost in the cleaning process. Bradley devised a mathematical model to measure the efficiency of a hydrocyclone, and it is still the accepted model today. Several problems may exist with the Bradley Model as it applies to paper making slurries. …


Lignosulfonate As A Strength Additive For Non-Wood Paperboard, Francisco L. Martin Dec 2000

Lignosulfonate As A Strength Additive For Non-Wood Paperboard, Francisco L. Martin

Paper Engineering Senior Theses

Recycle mills that use old corrugated cardboard (OCC) in their furnish experience difficulties in maintaining the quality of the paperboard produced. Recycle mills using the OCC collect their OCC from many parts of the world. Countries such as China and Japan use rice fibers in the production of corrugated cardboard. Other countries use straw as a fiber source. The end result is that OCC in the United States contains a portion of non-wood fibers as well as the typical wood fibers. Paperboard containing these non-wood fibers typically has lower strength properties than paperboard produced from pure wood fibers. Literature suggests …


The Influence Of Base Sheet Sizing On The Print Quality Of Matte Coated Ink Jet Papers, Saurabh K. Halwawala Dec 2000

The Influence Of Base Sheet Sizing On The Print Quality Of Matte Coated Ink Jet Papers, Saurabh K. Halwawala

Masters Theses

The most recent developments in ink-jet papers have been related to coating aμd pigment technology. Silica is the preferred pigment for matte coated ink-jet papers. Besides being expensive, the high surface area and porosity of this pigment limits the percentage coating solids to less than 30-35%, which increases production cost due to higher dryer loads. Thus, a need exists to develop a new generation of pigments. The objective of this research was to evaluate the effect of base sheet absorbency on the surface, as well as print properties of matte coated ink-jet papers using a new pigment capable of being …


Creating Virtual Wood Particulate Composites, Huaijun Wang Dec 2000

Creating Virtual Wood Particulate Composites, Huaijun Wang

Electronic Theses and Dissertations

Wood particulate composites are inhomogeneous, short fiber materials. The behavior of such materials depends on the properties of the constituent elements (wood particles, fibers, and adhesives) and the manner in which they are organized (the microstructure). Research on the microstructure of these composites has been carried out for several decades. However, due to the complexity of the engineered structures, most existing works are either over-simplified or lacking in general representations. While experimental approaches to improve material performance are necessary, this thesis presents another approach for better depictions of such complex systems. In this research project, digital surrogates of the composite …


Effect Of Size Level And Fiber Coarseness On Ink-Jet Printability Of Size Press Coated Paper, Falguni Mehta Dec 2000

Effect Of Size Level And Fiber Coarseness On Ink-Jet Printability Of Size Press Coated Paper, Falguni Mehta

Masters Theses

In recent years, matte coated paper has enjoyed wide spread usage for ink-jet applications. The coating performance is strongly influenced by base sheet properties including fiber coarseness and base sheet absorbency. Base sheet absorbency, which is elevated in terms of internal sizing, is a crucial property of ink-jet paper.

The objective of this research was to evaluate the influence of size level and fiber coarseness on ink-jet print qualities. A secondary objective was to examine the size reversion phenomena and to quantify the effect of size level, pigmented coating, and fiber coarseness on size reversion.

The results showed that the …


Development Of A Photoinitiator Blend For Uv Cured Inks And Coatings, Madhu Bansal Aug 2000

Development Of A Photoinitiator Blend For Uv Cured Inks And Coatings, Madhu Bansal

Masters Theses

The purpose of this study is to develop a new standard blend of photoinitiators, having properties of low odor, high solubility, faster curing, and being efficient for pigmented as well as for clear systems. In the process, we expect to understand the behavior of mixtures of photoinitiators and their resulting UV spectra. An important first step is to prepare different blend with different photoinitiator and characterize them on cure basis. Curing properties were studied by the KMnO4 yellow stain density test. The absorption range in the UV spectra was measured for each Photoinitiator with methanol and acrylate as background …


An Investigation Into The Influence Of Common Fillers On Color Reversion Of Bctmp Pulp, Joseph N. Mikowski Jun 2000

An Investigation Into The Influence Of Common Fillers On Color Reversion Of Bctmp Pulp, Joseph N. Mikowski

Masters Theses

Recent advances in the pulping and bleaching of high-yield pulps, particularly bleached thermomechanical pulp, have made these pulps suitable replacements for bleached kraft pulps. Unfortunately, these high-yield pulps are not appropriate for making high-grade papers because of their tendency to yellow. Extensive efforts have been made to reduce the yellowing, but none of the methods that have been investigated have been at once both practical and economical.

This study investigated the ability of common pigments used in the paper industry to reduce the extent of yellowing of an 80/20 blend of bleached chemithermomechanical and bleached softwood kraft pulp. The effectiveness …


Cutting Your Timberland Taxes, May 19-20, 2000, Arthur Temple College Of Forestry And Agriculture May 2000

Cutting Your Timberland Taxes, May 19-20, 2000, Arthur Temple College Of Forestry And Agriculture

eBooks

No abstract provided.


Borax As Internal Stock Additive In Papermaking, Nejib S. Yousef Apr 2000

Borax As Internal Stock Additive In Papermaking, Nejib S. Yousef

Masters Theses

The effect of borax on strength property of paper has been investigated in different ways. The use of borax either improved the physical properties or assisted in the reduction of refining energy to significant level.

The study of borax in the presence of precipitated and ground calcium carbonate was accomplished by using white water recycling. In the absence of retention aids, recycling of white was a necessary condition for the retention of ash content. As the ash content increased the strength property decreased. But the presence of borax slowed down the detrimental effect of fillers.

Sizing development progressively improved especially …


Wildland Fire In Ecosystems Effects Of Fire On Fauna, L. Jack Lyon, Mark H. Huff, Robert G. Hooper, Edmund S. Telfer, David Scott Schreiner, Jane Kapler Smith Jan 2000

Wildland Fire In Ecosystems Effects Of Fire On Fauna, L. Jack Lyon, Mark H. Huff, Robert G. Hooper, Edmund S. Telfer, David Scott Schreiner, Jane Kapler Smith

Joint Fire Science Program Synthesis Reports

Fires affect animals mainly through effects on their habitat. Fires often cause short-term increases in wildlife foods that contribute to increases in populations of some animals. These increases are moderated by the animals’ ability to thrive in the altered, often simplified, structure of the postfire environment. The extent of fire effects on animal communities generally depends on the extent of change in habitat structure and species composition caused by fire. Stand-replacement fires usually cause greater changes in the faunal communities of forests than in those of grasslands. Within forests, standreplacement fires usually alter the animal community more dramatically than understory …


Wildland Fire In Ecosystems Effects Of Fire On Flora, R. James Ansley, Stephen F. Arno, Brent L. Brock, Patrick H. Brose, James K. Brown, Luc C. Duchesne, James B. Grace, Gerald J. Gottfried, Sally M. Haase, Michael G. Harrington, Brad C. Hawkes, Greg A. Hoch, Melanie Miller, Ronald L. Myers, Marcia G. Narog, William A. Patterson Iii, Timothy E. Paysen, Kevin C. Ryan, Stephen S. Sackett, Dale D. Wade, Ruth C. Wilson Jan 2000

Wildland Fire In Ecosystems Effects Of Fire On Flora, R. James Ansley, Stephen F. Arno, Brent L. Brock, Patrick H. Brose, James K. Brown, Luc C. Duchesne, James B. Grace, Gerald J. Gottfried, Sally M. Haase, Michael G. Harrington, Brad C. Hawkes, Greg A. Hoch, Melanie Miller, Ronald L. Myers, Marcia G. Narog, William A. Patterson Iii, Timothy E. Paysen, Kevin C. Ryan, Stephen S. Sackett, Dale D. Wade, Ruth C. Wilson

Joint Fire Science Program Synthesis Reports

This state-of-knowledge review about the effects of fire on flora and fuels can assist land managers with ecosystem and fire management planning and in their efforts to inform others about the ecological role of fire. Chapter topics include fire regime classification, autecological effects of fire, fire regime characteristics and postfire plant community developments in ecosystems throughout the United States and Canada, global climate change, ecological principles of fire regimes, and practical considerations for managing fire in an ecosytem context.


Evaluating The Durability Of Wood/Frp Bonds Through Chemical Kinetics Using A Range Of Mechanical Test Methods, Jonathan Philip Alexander Jan 2000

Evaluating The Durability Of Wood/Frp Bonds Through Chemical Kinetics Using A Range Of Mechanical Test Methods, Jonathan Philip Alexander

Electronic Theses and Dissertations

Hybrid composites of wood and fiber reinforced polymers (FRP) exhibit a flexibility of design properties through choices in fiber type, amount, orientation and resin type. With this flexibility comes the need to measure the durability of the composite material system, especially the bond between these two materials due to their markedly different responses to moisture. This study is two-fold; the first section examines methods for the mechanical testing and durability of wood/FRP laminations. Six mechanical tests were evaluated and a modified block shear method was identified as the most suitable due to its ability to provide representative results independent of …