Word: lignin
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Books are decaying rapidly today because "a tree had more to it than a cotton ball," says Merrill-Oldam. The problem is that wood contains lignin, the substance that causes newsprint even today to decay and yellow within a matter of weeks if left...
...scientists had determined the problem and began treating the wood to remove the lignin, but in the process they often reintroduced other decants and acids. In the '50s and '60s, paper was sized-smoothed out for writing--with acidic salts--another decant. It was not until the 70s that mills were reengineered to manufacture alkaline paper, which, like paper made from cotton rags, has an extremely long life...
...Molecular biologist Manuel Raices helped develop a recombinant enzyme that dissolves dextran, a sticky substance that gums up the sugar-refining process. In tests conducted by local sugar mills, the enzyme reduced oil consumption up to 45%. Now Raices is working with Swedish researchers on an enzyme that digests lignin, a gluelike material that bedevils paper manufacturers...
...encounter bacteria in the large bowel. There are three basic kinds of fiber. The simplest is cellulose; the four-chambered stomach of cattle can readily digest this form, but the single human stomach cannot. Next comes a group of polysaccharides, consisting of complex sugar chains. The third type is lignin, which not even intestinal bacteria can degrade. Fiber of any kind provides little caloric nourishment; its main value is in absorbing water so that the contents of the digestive tract are bulky, loose and easily excreted. Grandma knew this when she advised her family to eat more fruits and vegetables...
...studies, Dr. Lewin does not yet know in detail how bromine fireproofing works, but in general the action is connected with the way that wood burns. When heat is applied to natural lignin and cellulose, they give off combustible gases that form flames and spread the fire by heating more wood. Somehow, bromine seems to make those gases nonflammable. And with no flames to spread it, combustion stops as soon as the external heat source, such as a lighted match, is removed...