due to its toxicity, most cities moved away from lead water-supply piping by the 1920s in the united states, although lead pipes were approved by national plumbing codes into the 1980s, and lead was used in plumbing solder for drinking water until it was banned in 1986. drain and vent lines are made of plastic, steel, cast iron, or lead.
coltan short for columbite–tantalites and known industrially as tantalite is a dull black metallic ore from which are extracted the elements niobium and tantalum.the niobium-dominant mineral in coltan is columbite after niobium's original american name columbium , and the tantalum-dominant mineral is the tantalite.. tantalum from coltan is used to manufacture tantalum capacitors which are .
the first blasting cap or detonator was demonstrated in 1745 when british physician and apothecary william watson, f.r.s., showed that the electric spark of a friction machine could ignite black powder, by way of igniting a flammable substance mixed in with the black powder.
portable appliance testing pat, pat inspection or redundantly as pat testing is the name of a process in the united kingdom, the republic of ireland, new zealand and australia by which electrical appliances are routinely checked for safety. the formal term for the process is 'in-service inspection & testing of electrical equipment'. testing .
ultrasonic cleaning is a process that uses ultrasound usually from 20–40 khz to agitate a fluid.the ultrasound can be used with just water, but use of a solvent appropriate for the object to be cleaned and the type of soiling present enhances the effect.
lead poisoning is a type of metal poisoning caused by lead in the body. the brain is the most sensitive. symptoms may include abdominal pain, constipation, headaches, irritability, memory problems, inability to have children, and tingling in the hands and feet. it causes almost 10% of intellectual disability of otherwise unknown cause and can result in behavioral problems.
coltan short for columbite–tantalites and known industrially as tantalite is a dull black metallic ore from which are extracted the elements niobium and tantalum.the niobium-dominant mineral in coltan is columbite after niobium's original american name columbium , and the tantalum-dominant mineral is tantalite.. tantalum from coltan is used to manufacture tantalum capacitors which are .
an electromagnet is a type of magnet in which the magnetic field is produced by an electric current.electromagnets usually consist of wire wound into a coil.a current through the wire creates a magnetic field which is concentrated in the hole, denoting the centre of the coil.
the dolaucothi gold mines pronounced ˌdɔlaiˈkɔθɪ ; welsh: mwynfeydd aur dolaucothi grid reference , also known as the ogofau gold mine, are ancient roman surface and underground mines located in the valley of the river cothi, near pumsaint, carmarthenshire, wales.the gold mines are located within the dolaucothi estate which is now owned by the national trust.
sherrod campbell brown / ˈ ʃ ɛr ə d /, born november 9, 1952 is an american politician serving as the senior united states senator from ohio, a seat to which he was first elected in 2006.a member of the democratic party, he was the u.s. representative for ohio's 13th congressional district from 1993 to 2007 and the 47th secretary of state of ohio from 1983 to 1991.
a buddle pit or buddle pond is a pit, often circular when specifically constructed, the purpose of which was to separate by sedimentation minerals from lighter rock dust in crushed ore, and used in the mineral mining industry such as in extracting tin, lead and zinc . many of the relics seen today date from victorian times.
however, there might be impurities in the lead ore other elements which have short enough half-lives that they significantly decay over millions of years. sturat 22:17, 22 october 2013 utc what stu said is right. the radiation is not coming from lead, but from contaminants. i hadn't thought of that wrinkle.
dressing was the process of extracting the ore from the rock in which it was embedded and washing it, a further refining process. in the days of bole smelting the ore was roughly washed clean of waste minerals and dirt before being riddled for bing ore. the ore for the new smelters was smashed, or crushed, into pieces about the size of peas.