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- Map (10223 bytes)
7: ...h-central [[Anatolia]] (now [[Turkey]]); it dates from about [[6200 BC]].
9: ...tical value, and this has been the source of much fruitful map criticism over the last twenty years, n...
49: From the last quarter of the 20th century, the indis...
51: From the computer scientist's standpoint, zooming in...
55: ...quid crystal display|LCD]], but may apply for a [[cathode ray tube]]), then replacing a pixel by a rectangl... - Timeline of invention (28171 bytes)
6: * 2.4 MYA: [[Oldowan|Stone tools]] in [[Africa]]
8: ...YA: Controlled [[fire]] in [[Cradle of Humankind|Africa]]
26: * [[Cloth]] woven from [[flax]] fiber
112: * [[1589]]: [[Stocking frame]]: [[William Lee]]
134: ...quadrant]]: [[Thomas Godfrey (inventor)|Thomas Godfrey]] - List of inventors (14020 bytes)
12: *[[Manfred von Ardenne]], (1907-1997), [[Germany]]
39: ...inand Braun]], (1850-1918), [[Germany]] — [[cathode ray tube]]
53: *[[Jacques-Yves Cousteau|Jacques Cousteau]], [[France]] — [[Aqua-Lung|aqualung]]
56: ...illiam Cullen]] — mechanical / chemical [[refrigeration]]
87: *[[Benjamin Franklin]], (1706-1790), [[United States|USA]] &mdas... - Philo Farnsworth (6489 bytes)
1: ...[[inventor]] credited with the invention of the [[cathode ray tube]] [[television]].
7: ...ater moved to the [[San Francisco, California|San Francisco]] Bay area with his bride, Elma G. "Pem" F...
19: ... The [[cathode ray tube]] configuration developed from Farnsworth's work was used in all television se...
31: ...Street location of his research laboratory in San Francisco. - Capacitor (29664 bytes)
9: [[Image:Dielectric.png|frame|The electrons in the molecules shift toward th...
14: :<math>C = \frac{Q}{V}</math>
32: :<math>i(t) = C \frac{dv(t)}{dt}</math>
34: The [[impedance]] in [[frequency domain]] can be written as
36: :<math>Z = \frac{1}{j \omega C} = - j X_C </math> - Electron microscope (5936 bytes)
11: High [[voltage]] electron beams from a [[cathode]] are focused by [[magnet]]ic lenses on to the sp...
14: ...y detecting secondary electrons which are emitted from the surface due to excitation by the primary el...
22: *''Cryofixation'' - freezing a specimen so rapidly, to liquid nitrogen t...
28: ...the surface from an angle and sputtering material from the surface. A subclass of this is Focussed Ion...
36: ...his gives the problem of distinguishing artifacts from material, particularly in [[biology|biological]... - Electricity (13894 bytes)
6: ...eek]] ''ēlektron'' = "[[amber]]", which came from an old [[root (linguistics)|root]] ''ēlek-...
10: ..., and coined the modern Latin word ''electricus'' from ''ηλεκτρ&omicr...
12: ...[[Ebenezer Kinnersley]] of [[Philadelphia]] (less frequently) who created the convention of positive a...
16: Franklin's observations aided later scientists such ...
18: ...ively charged [[anode]]s and negatively charged [[cathode]]s. When a conductor was attached between these, ... - Wilhelm Conrad Roentgen (8624 bytes)
6: .... He later attended [[Utrecht Technical School]], from which he was expelled for producing a caricatur...
8: ...e graduated with a [[Doctor of Philosophy|Ph.D.]] from the [[University of Zurich]].
16: ...scaping, yet Röntgen observed that the invisible cathode rays caused a [[fluorescense|fluorescent]] effect...
18: ...ng a match, he discovered the shimmering had come from the location of the barium platinocyanide scree...
20: ...nd of ray might be responsible. November 8 was a Friday, so he took advantage of the weekend to repea... - Barium (8466 bytes)
154: ...pure form. It is primarily found in and extracted from the [[mineral]] [[barite]] which is crystalized...
156: :([[cathode]]) Ba<sup>2+</sup>* + 2[[electron|e<sup>-</sup>]]...
167: ...t does not dissolve, and is eliminated completely from the digestive tract. - Shadow mask (2096 bytes)
1: ...anner ensuring that [[electron]]s from the tube's cathode gun reach the appropriately-colored portion of th...
5: ...ess and damage to the shadow mask that can result from repeated expand/contract cycles, thus increasin... - Chlorine (10751 bytes)
39: '''Chlorine''' (from the [[Greek language]] ''Chloros'', meaning "pa...
44: ... [[salt]]-forming halogen series and is extracted from chlorides through [[oxidation]] and more common...
50: ...to kill [[bacterium|bacteria]] and other microbes from [[drinking water]] supplies and [[swimming pool...
73: ...Chlorine has 9 isotopes with mass numbers ranging from 32 to 40. Only three of these isotopes occur na...
90: ...des, whilst the sodium dissolves into the mercury cathode forming an amalgam. - Copper (13595 bytes)
136: ...d because so much of it was mined in [[Cyprus]]). From this, the phrase was simplified to ''cuprum'' a...
138: ...ns of copper [[smelting]], the refining of copper from simple copper oxides such as [[malachite]] or [...
140: There are copper and [[bronze]] artifacts from [[Sumerian]] cities that date to 3000 BC, and [...
142: ... an animal skin, a typical shape of copper ingots from these times.]]
160: ...e Upper Intake Level for adults of dietary copper from all sources is 10 mg/day. - Magnesium (9193 bytes)
7: ...of this metal is to aid the removal of [[sulfur]] from iron and steel.
15: ...e production of pure [[uranium]] and other metals from their [[salt]]s.
17: * Dead-burned magnesite is used for refractory purposes such as brick and liners in furnac...
21: ...ing of [[tablet|tablets]], to prevent the tablets from sticking to the equipment during the tablet com...
26: The name originates from the [[Greek language|Greek]] word for a distric... - Aluminium (26079 bytes)
48: ...the [[world economy]]. Structural components made from aluminium are vital to the [[aerospace]] indust...
58: ...so coated with a thin layer of aluminium, but are front coated to avoid internal reflections even thou...
82: ...lue if people started producing this bright metal from clay. Therefore, instead of giving the goldsmit...
86: ...in bauxite ore and successfully extracted it. The Frenchman [[Henri Saint-Claire Deville]] improved W?...
88: ...t process]] in [[1886]] made extracting aluminium from minerals cheaper, and is now the principal meth... - Radium (13138 bytes)
4: <tr><td colspan="2" align="center">[[Francium]] - '''Radium''' - [[Actinium]]</td>
100: When freshly prepared, pure radium metal is brilliant whi...
103: Some of the practical uses of radium are derived from its radiative properties. More recently discove...
104: ... who used their lips to shape the paintbrush died from the radiation. Soon afterward, the adverse effe...
110: ...lution by using a [[mercury (element)|mercury]] [[cathode]] and [[distillation|distilling]] in an atmospher... - Silver (15157 bytes)
136: ...ty of any metal and occurs in [[mineral]]s and in free form. This metal is used in [[coin]]s, [[jewelr...
140: ...[[copper]], but its greater cost has prevented it from being widely used in place of copper for electr...
151: ...elry and silverware, which are traditionally made from the silver alloy known as [[Sterling silver]], ...
153: ...; for example, the production of [[formaldehyde]] from [[methanol]] and air by means of silver screens...
160: ...Silver oxide]] is used as a positive electrode ([[cathode]]) in watch batteries. - Strontium (11493 bytes)
173: ...kept under [[kerosene]] to prevent [[oxidation]]; freshly exposed strontium metal rapidly turns a [[ye...
176: ...ontium is in [[glass]] for [[color]] television [[cathode ray tube]]s.
181: *[[Strontium titanate]] has an extremely high [[refractive index]] and an [[optical dispersion]] great...
188: ...nd|Scottish]] town of [[Strontian]], as differing from other [[barium]] minerals in [[1790]].Hope disc...
191: ...>3</sub>). Of the two, celestite occurs much more frequently in sedimentary deposits of sufficient siz... - Computer display (4276 bytes)
6: * [[Cathode ray tube]] (CRT)
11: ...048ױ536) with 32-bit colour and a variety of [[refresh rate]]s.
24: ...by [[Microsoft]] ([[ClearType]], [[1998]]) and [[XFree86]] ([[X Rendering Extension]]).
26: ...delay causes an apparent corresponding shift of a fraction of a [[pixel]].
45: * [[Refresh rate]] - Electron (10516 bytes)
39: ...18(44) [[MeV]]{{inote|http://scienceworld.wolfram.com/physics/ElectronMass.html}}
54: ...rd ''electron'' was coined in 1894 and is derived from the term ''electric'', whose ultimate origin is...
70: ...e vibrations called phonons. When electrons move, free of the nuclei of atoms, and there is a net flow...
74: ...its vicinity, so that the properties one observes from far away are the sum of the bare properties and...
78: ...Note that this is the radius that one could infer from its charge if the physics were only described b... - Magnet (13875 bytes)
4: ...s a [[magnetic field]]. The word ''magnet'' comes from the [[Greek language|Greek]] ''"magnítis...
48: ...s are and all of the backs are. The person at the front of the face end has a back; and the person at ...
56: ...between magnets and the earth's magnetic field. A freely suspended magnet will eventually orient itsel...
70: *[[Refrigerator]] magnets
72: ...magnet to generate an image--see the article on [[cathode ray tube]]s for more information. [[Plasma screen... - Ion (2800 bytes)
4: ...particles that can be removed. The formation of ''free'' negatively charged atomic ions is non-trivial...
11: ...ired to produce a cation by stripping an electron from a more nearly neutral atom is the [[ionization ...
16: ... molecules that travel either to an anode or to a cathode. However, the mechanism by which this was achieve...
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