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Updated: Jun 29, 2026

10:47
Manufacturing Of Robust Natural Fiber Preforms Utilizing Bacterial Cellulose as Binder
Published on: May 22, 2014
Exposure to asbestos in the use of consumer spackling, patching, and taping compounds
Abstract:
Analysis of representative samples of spackling, patching, and jointing compounds, purchased at retail stores in the New York City area, has shown that some contain asbestos minerals as well as other biologically active substances. Measurements suggest that home repair work involving the use of such materials may result in exposure to dust at concentrations sufficient to produce disease.
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Types of Step-Growth Polymers: Polyesters
The introduction of polyesters has brought major development to the textile industry. The wrinkle-free behavior of polyester blends has eliminated the need for starching and ironing clothes.
Polyesters are commonly prepared from terephthalic acid and ethylene glycol; the crude product is known as poly(ethylene terephthalate) or PET. However, polyesters are synthesized industrially by transesterification of dimethyl terephthalate with ethylene glycol at 150 °C. The two reactants and the polymer...
Polyesters are commonly prepared from terephthalic acid and ethylene glycol; the crude product is known as poly(ethylene terephthalate) or PET. However, polyesters are synthesized industrially by transesterification of dimethyl terephthalate with ethylene glycol at 150 °C. The two reactants and the polymer...
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In healthcare, the chemical method of sterilization uses chemical sterilants to treat surgical instruments and medical supplies to help prevent the transmission of infectious pathogens to patients. Due to heat sensitivity, most medical supplies and equipment should not be exposed to high temperatures. These parts include rubber, plastic, glass, and other similar elements.
Using chemical sterilization rather than heat to clean out equipment is recommended. It eradicates and removes all bacteria,...
Using chemical sterilization rather than heat to clean out equipment is recommended. It eradicates and removes all bacteria,...
PPE Use in Healthcare Settings I: Donning
Donning PPE must be completed before contact with the patient. This process protects from infectious agents. The sequence and action included in each donning are critical, and the steps must be systematic to avoid exposure to pathogens. The institutional policy also needs to be followed while donning PPE. The pre-donning preparations are gathering equipment, inspecting the PPE equipment for tears, holes, or damage, removing jewelry, removing any garments below the elbows, and tying the hair...
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Water-reducers, or plasticizers, are chemical admixtures used in concrete to improve strength and workability. These additives reduce the water-cement ratio without compromising workability, lower the cement content while maintaining the same workability, or increase workability to assist concrete placement in inaccessible areas.
Plasticizers function by using surface-active agents to create repulsive electrostatic forces between cement particles. This dispersion enhances the concrete's...
Plasticizers function by using surface-active agents to create repulsive electrostatic forces between cement particles. This dispersion enhances the concrete's...
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Additives and fillers are integral to enhancing the properties of concrete. Pozzolans and blast-furnace slag are additives or admixtures due to their reactions with calcium hydroxide released during cement hydration. Fillers, which are finely ground and similar in fineness to Portland cement, improve concrete attributes such as workability density, and reduce capillary bleeding or cracking. Some fillers possess hydraulic properties or participate in benign reactions within the cement paste.
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