Weights, of paper

Krypton-85 has been used for over 25 years to measure the density of paper as it is amanufactured. The total weight of paper can be controlled to a very accurate degree by the use of krypton 85 and other radioactive nuclides. The common name for such a device is a beta gague that can measure the thickness of a material. 

Depth (cm) Weight of Paper Filter (g) Weight of Evaporating Dish (g) Weight After Drying (g) Weight After Ashing (g)... 

Drape can be measured by placing a circular fabric specimen over a round table or pedestal and viewing from direcdy overhead. A drape coefficient is defined as the ratio of the area of the fabric s actual shadow to the area of the shadow if the fabric were rigid. Drape is closely related to stiffness the drape coefficient for a stiff fabric approaches a value of 1 a limp fabric has a drape coefficient near 0. The Cusick drape tester is an example of this type of measurement. Eor this method, the relative weights of paper rings representing tracings of the fabric s shadows are used to calculate drape coefficient. 

In the Italian Official Method (1905), the milk is mixed, before evaporating, with about an equal weight of paper, previously dried and extracted with petroleum ether, or a somewhat greater weight of powdered pumice. 

Paper is sold by weight. Different grades of the same type of paper are distinguished by the weight of some standard quantity of that paper. For most of the world, the standard quantity is one sheet of paper per one square meter in area. In the United States, the system of basis weights is used to compare the weights of papers. The standard quantity is one ream, or 500 sheets, but the standard sheet size varies from one cat ory of paper to another. For book papers, the standard sheet measures 25 x 38 in (64 x 97 cm). For cover stocks, the standard size is only 20 x 26 in (51 x 66 cm), so a 50 lb (23 kg) cover paper is nearly twice as heavy as a 50 lb (23 kg) book paper. For bond papers, the standard size is 17 x 22 in (43 x 56 cm), so a 20 lb (9 kg) bond is approximately equal to a 50 lb (23 kg) book paper. 

Surface of water bends 5 to accommodate weight of paper clip... 

A new indicator, CO2 Emissions/Production has been introduced in order to observe its relation with the variables of machine availability arising from maintenance. The result obtained indicates initially that this ratio can be useful in identifying variables with which to improve plant efficiency and sustainability, although this will require analysis of daily data. This study also shows that there may be other variables that may influence the indicator such as the quality of product manufactured and the weight of paper. Each quality manufactured has a different formulation both of raw materials and of added products, which may yield specific characteristics with regard to the ease of removing the water it contains and therefore a different initial CO2 Emissions (ton)/Production (ton) indicator level. 

Plastics are also energy-efficient compared with traditional materials [1]. It takes twice the weight of paper to effectively protect goods than in the case of polyethylene and if all the plastics currently used in packaging were to be replaced by paper, the effect on the environment would be catastrophic in terms of forest depletion, increased energy utilisation and damage to the environment [2,3]. This ecologically important characteristic of the polyolefins will be discussed in more detail in Section 4. 

While this may seem obvious, there are many examples of procedures where it has clearly not been apphed. For example, it has been reported that the total weight of paper used for instructions/procedures in the design of a major civil aircraft was actually heavier than the aircraft itself. 

The camphorquinone can be purified in either of two ways, (i) To save time, the drained but still damp material can be recrystallised from water containing 10% of acetic acid, the hot filtered solution being cooled and vigorously stirred. The quinone separates as brilliant yellow crystals (yield, 2 5 g.), m.p. 192-194 , increased to 196-197 by a second reciystal-lisation. (ii) The crude camphorquinone can be dried in a vacuum desiccator (weight of dry quinone, 5 g.), and then recrystallised from petroleum (b.p. 100-120 ), the hot solution being filtered through a fluted paper in a pre-heated funnel. The quinone separates in beautiful crystals, m.p. 196-197 , 2 8 g. 

Two oxidants commonly used are chlorine and potassium permanganate. The Roe chlorine number, the uptake of gaseous chlorine by a known weight of unbleached pulp (ie. Technical Association of the Pulp and Paper Industry (TAPPl) Standard Method T202 ts-66) has been superseded by the simpler hypo number (ie, TAPPl Official Test Method T253 om-86), eg, chlorine consumption in treatment of the pulp with acidified sodium or calcium hypochlorite. 

The type of varnish used in the process depends on the kraft paper manufacturer and basis weight of the papers the machine, temperature, and control (scraper bars, squeeze roUs) used the method of cutting the paper to size the laminate being produced (post-forming or regular) and the press-cure cycle (see Laminated materials, plastic). 

A number of papers and patents describe polymerization processes to poly(tetramethylene ether) glycols having a narrow molecular weight distribution = 1.2—1.4). In principle, this can be achieved by having all chains grow quickly at one time, either by high temperature initiation (33)... 

A pilot plant ia India has been estabUshed to extract fiber, pulp, and juice from the leaves of sisal plants. The fiber is sold direcdy or used to manufacture rope, the cmshed pulp is used ia paper processiag, and the juice is an excellent source of hecogenin. During a three- to five-day fermentation of the juice, partial enzymatic hydrolysis causes hecogenin to precipitate as the hemisaponin ia the form of a fine sludge. This sediment is hydrolyzed with aqueous hydrochloric acid, neutralized, and filtered. This filter cake is washed with water and extracted with alcohol. The yield of hecogenin varies between 0.05 and 0.1% by the weight of the leaf (126). 

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