CHOPPING BOARD

Of course you ll come back. She nodded toward the block where the knives were kept, which I took to be an invitation to join her at the chopping board, though I could only peel half a dozen onions to her twenty. 

A study in Japan looked at the migration of dimethylamine (DMA) into water and hydrochloric acid from 25 rubber articles (including stoppers, chopping boards, spatulas and teats). After one hour of refluxing, the water extracts contained 3 to 1280 mg of DMA per kg of rubber. The study also showed that the thiuram accelerators that were present (TMTD and TMTM) were almost totally decomposed to DMA (a nitrosatable substance). However, in the case of dimethyl dithiocarbamate salts (sodium, zinc, copper and lead examples were included), the decomposition to DMA depended on the solvent used and the salt compound. 

These biocides are usually provided to offer a value added component to existing applications. An example would be an anti-bacterial chopping board promoted as a safer alternative to a board that does not claim to have any anti-bacterial additive. However, there are no internationally recognised test methods available to prove the performance of such systems and so most applications are based either on certain laboratory test protocols, anecdotal evidence of performance or by marketing claims alone. 

Patent Number US 5562872 A 19961008 A METHOD FOR MANUFACTURING AN ANTIBACTERIAL CHOPPING BOARD... 

Patent Number US 5433424 A 19950718 ANTI-BACTERIAL CHOPPING BOARD... 

Zip-lock bags, carrier bags, microwave-safe shrinkwrap food film, Tupperware containers, food chopping boards, food packaging films, milk, bread and beer crates, water pipes, electrical cable insulation, geo-textiles, replacement body parts (e.g. heart valves, artificial arteries, hip Joints). ... 

A different use for antimicrobials is in polymers that are inherently resistant to microorganisms and do not contain susceptible additives, but are frequently used in hygiene-conscious environments like hospitals, bathrooms and kitchens. There has been a rapid increase in the use of antimicrobial additives in the last four years to protect or reassure the user, rather than the product. Typical applications include kitchen surfaces and chopping boards, toothbrushes, rubbish cans, air filters, mattresses, and the ceilings, wallcoverings and floors of canteens and hospitals. Certain medical devices may also have biocidal protection. 

A carpenter is a person who has to solve a variety of problems in the physical world by using tools to build, repair, and maintain things. A good carpenter, one who is competent at a variety of jobs, has many tools available and knows how to use them. He has hammers, saws, rulers, squares, nails, chisels, and so forth. He uses the saws to cut, not to hammer the hammers to drive nails, not to chop through boards. A poor carpenter would be one who doesn t have the necessary tools to do the job, or who can t improvise adequately from the tools he does have. A poor carpenter could also be one who has the necessary tools but doesn t know how to use them properly, or, for whatever reasons, won t use them properly. 

Aramid para-aramid, 2.8 Pa strength, 70 GPa modulus chopped staple or fibrid (pulp) 10-150 g/m2 Tensile strength up to 8 N/mm Density 80 kg/mm Improved impact resistance Smooth finish Good wear resistance Can be blended with conductive fiber Superior temperature resistance Aerospace adhesive carriers Automotive improved stone impact resistance Defence radar cross section Recreation skis, snow and surf boards, surf boards, canoes Industrial substrate for friction products wear resistance for high-speed rolls Electrical printed circuit boards... 

Rovings are essentially untwisted bundles of fiberglass strands wound up in parallel on cylindrically shaped packages. They are used in open lay-up moldings, woven fabrics, rods, and tubes. Woven rovings are used for open lay and press moldings. Yams [1] consist of twisted yam bundles. Weaver yarns are used for electrical and aircraft laminates, insulating tape, window shades, and filtration applications. Their major use is in printed circuit boards. Chopped strand serves as a reinforcement in a variety of markets. For example, it is used to... 

The excellent electrical insulation property of E-glass has found many applications in this field. Fabrics made of textile glass yarn is the backbone of the printed circuit board of the modern electronic industry. Polybutene terephthalate, polyphenylene sulfide, and liquid crystal polymer reinforced with chopped glass fiber are also widely molded into electronic components (23). 

The chopping operation usually takes place thanks to a saw mounted on a board moving parallel to the pultrusion direction and moving at the same driving speed of the object. As a consequence, the relative speed will be null. Once the operation has been accomphshed, the saw returns back to the starting position to repeat the chopping. The saw blades are made out of silicon carbide or are diamond-coated. 

One of the most critical requirements for electronic surface-mount components is the CTE. In this respect, LCPs are unique in that their thermal expansion properties can be tailored by the judicious incorporation of reinforcements (such as short glass fibres and chopped carbon fibres) and fillers (such as talc, silica and calcium carbonate). Figure 7.9 illustrates the thermal expansion of LCPs and how they compare with other engineering materials. The CTE can be adjusted within the wide limits to practical requirements by varying the processing conditions, and can approach that of FR4 epoxy/glass fibre - one of the most widely used substrates for printed circuit boards. Other application-related examples are discussed in section 7.5. 

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