Paper life expectancy

The paper by Cochrane, St. Leger, and Moore (1978) typifies the issues associated with many early studies. Specifically, they relied on cross sections with multiple countries and often limited the analysis to simple correlations. Because determinants of life expectancy are multifactorial, national studies are more likely to detect differences than international studies. It is also critically important to include adequate control variables. In fact, a later study (Cremieux, Ouellette, and Meilleur 1999) based on extensive national data suggests that a 10% increase in health care spending reduces infant mortality by 0.5% for males and 0.4% for females while increasing life expectancy by half a year for males and three months for females. The current study uses similar modeling and data hence, results on the effect of pharmaceuticals reported below can be put in perspective relative to the overall effect of health care spending from that earlier research. 

These data would suggest that, although there is some loss of ascorbic acid during the normal shelf life of orange juice in plastic-coated paper cartons, this processed product represents a significant source of ascorbic acid in the diet of any consumer at any time during its dated life expectancy (as indicated by the... 

Ironically, modern papers, which were invented after the revolutionary changes of one hundred years ago, have serious problems—either in permanence or in durability. Most paper produced from wood fibers does not show the permanence of rag papers and discoloration is more critical than in rag papers. It has been noted that modern writing papers and books tend to have a much shorter life expectancy than those manufactured one hundred years ago. 

A Means of Strengthening Paper and Increasing the Life Expectancy of Cellulosic Archival Material... 

The larger proportion of archival and modern information is stored on materials with a limited life expectancy. These materials Include, paper, film, magnetic tape and optical disc. Paper, the major storage medium to date, is known to become brittle and discoloured with increasing age. This is particularly true of paper manufactured since the 1850 s. 

The case of reactors with two unmixed feedstreams is especially interesting (6), because more realistic for applications. It has been thoroughly investigated in a series of papers by researchers of Exeter University (UK). The BPT model offers a convenient picture of the reactor where both feed streams have their own RTD and the two bundles are placed side by side in such a manner that particles with the same life expectancy are situated as usual on the same vertical line (figure 6). In a first paper (60), a distinction is made between age mixedness and species mixedness Maximum age and species mixedness is achieved if particles with the same life expectancy are mixed. A more restrictive case is that where particles are able to mix only if they have both the same... 

Most modern papers have a reasonable life expectancy of about 50 years. Permanent paper is paper that can have a reasonable life expectancy exceeding 200 years. The important phrase in this definition is reasonable life expectancy. Permanent paper is still a fragile commodity, and the papermaker has no control over paper processors and ultimate users or abusers. 

Factors Affecting the "Reasonable Life Expectancy of Paper... 

An acid papermaking environment is corrosive. In the same manner that acidity can affect the reasonable life expectancy of paper by breaking down the amorphous structure of cellulose, acidity can affect the reasonable life expectancy of the working parts of a paper machine by corroding the exposed metal surfaces. An alkaline papermaking environment is noncorrosive, extends life, and reduces maintenance costs. Paper machine systems get dirty, and dirt affects the quality of the paper. 

Life Expectancy Estimates. If the end of the useful life of a paper is arbitrarily defined as a folding endurance of one double fold, rate-of-fold-loss lines such as those in Figure 4 can be extrapolated until they reach one double fold, and the corresponding accelerated-aging intercepts on the time axis can be compared directly. This gives a measure of the extent of improvement resulting from treatment. 

Modem papers, which were invented after the revolutionary changes of one hundred years ago, have serious problems—either in permanence or in durability. Most paper produced from wood fibers does not show the permanence of rag papers and discoloration is more critical than in rag papers. It has been noted that modern writing papers and books tend to have a much shorter life expectancy than those manufactured one hundred years ago (4-9). In essence, the increased use of wood fibers, the use of chemical additives (especially those promoting increased acidity), and environmental conditions have been given to account for these results. The literature dealing with these topics is now very large it would not be wise to attempt an extensive review here in addition to those that already exist (6,10-19). It is my intention in this chapter to consider the discoloration of modern papers, and the inhibition or the control of discoloration. 

Retention requirements for electronic records are discussed in Chapter 12. It is important to remember that electronic data capture can undermine data integrity. Image capture techniques may reproduce an original record very accurately, but if the original has insufficient dots per inch for clear reading, then the reproduction may not be usable. Electronic records are often not nearly as rugged and durable as their paper counterparts. The following factors may affect their life expectancy ... 

The members of the freshman class were given appointments for a medical examination. According to verbal instructions, all of us in our group got in line, nude, and filed past three doctors. Each student handed in a paper on which he had filled out a medical questioimaire. The doctors asked questions and made some simple examinations. At the end of the examination I was told that my life expectation was between thirty and forty years. I regarded the or forty as good news, but from what I had read, I really did not believe it. 

This paper reviews the maintenance of both disc and shoe systems, life expectancy of discs and brake paths and the methods of restoration or replacement of brake discs will be discussed. 

On Sept. 19, 1958 there was published in Science a paper by Dr. Miriam P. Finkel of Argonne National Laboratory in which she communicated her observations on the effects of strontium-90 injected into mice on life expectancy and on incidence of tumors of bone and blood-forming tissues. She discussed the question of whether or not the effects are proportional to the amount of injected strontium-90 at low doses, and reached the conclusion that it is likely that there is a threshold with value for man between 5 and 15 /ic. (as compared with the present average value from fallout, about 0.0002 y-o,., and the predicted steady-state value from fallout for testing of nuclear weapons at the average rate for the past five years, about 0.02 yc.). Her paper ends with the sentence In any case, the present contamination with strontium-90 from fallout is so very much lower than any of these levels that it is extr nely unlikely to induce even one bone tumor or one case of leukemia. ... 

FIGURE 14.21 Estimated lifetime of an IBM WORM disk. Lognormal plot of lifetimes for shelf and archival use. (Source Wong, J.S. et aL, 1993. Life expectancy of IBM write-once media. IBM White Paper, IBM Publications.)... 

Other social aspects such as food, meat, fish and paper consumption, the share of Internet users in the population, life expectancy at birth, use of private cars per 100 people, and the annual consumption of motor gasoline and diesel oil are listed in Table 5.1.5 as these aspects are also linked to the energy demand and the standard of living. 

Country Annual energy consumption (2007) (toe pc) Daily food consumption (2005) (kcal pc) Annual paper consumption (2005) (kg pc) Level of science technology (2003) Share of Internet users (2008) (%) Life expectancy (2010) in years Road traffic (2005) Number of Annual fuel cars (per consumption 100 people) (liters pc) ... 

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