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2009/04/26 20:10:31瀏覽320|回應0|推薦0 | ||
A274(3)-金銀珠寶人人愛 JCW, 2009/04/25.版權所有. ★☆★☆★ 超快速交通車: 用滑鼠左鍵點一下就可進入 ▼ (1). "未來世界的政治主張" 原稿,請看:https://city.udn.com/61613/forum 世聯WodFed城市 (2). "未來世界的政治主張" 整理後稿件,請看:http://blog.udn.com/jcwang00/article 世聯城的部落格 (3). 說笑雜項,請看:http://blog.udn.com/jctheoldman 用膝蓋想部落格 (4). 接龍創作,請看:http://blog.udn.com/JC00 外太空的009部落格 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ "金銀珠寶人人愛!"……本文將討論下述各點: (1). 計量單位 (Units) (2). 珠寶及寶石 (Jewery and Precious Stones) (3). 鉑 (白金,Platinum) (4). 金 (黃金,Gold) (5). 銀 (Silver) (6). 紙幣 (Banknote) (續前...................) [4B.中文]:金,http://zh.wikipedia.org/wiki/%E9%87%91 金是一種化學元素,化學符號是Au,原子序數是79。金是一種廣受歡迎的貴金屬,在幾世紀以來都被用作貨幣、保值物(store of value)及珠寶。在自然界中,金出現在岩石中的金塊或金粒、地下礦脈及沖積層中。金亦是貨幣金屬之一。金在室溫下為固體、密度高、柔軟、光亮,其延展性及延性均是已知金屬中最高的。純金的亮黃色在傳統上被認為具有吸引力。 在佈雷頓森林協定結束前,金是金本位貨幣制度的基石。金條的ISO貨幣代碼是XAU。 金在現代工業的應用層面有牙醫學與電子學。在傳統上,金對氧化侵蝕的高抵抗性是人們使用它的原因之一。 化學上,金是一種過渡金屬,在溶解後可以形成三價及單價正離子。金與大部分化學物都不會發生化學反應,但可以被氯、氟、王水及氰化物侵蝕。金能夠被水銀溶解,形成汞齊(但這並非化學反應);能夠溶解銀及卑金屬的硝酸不能溶解金。以上兩個性質成為黃金精煉技術的基礎,分別稱為「加銀分金法」(inquartation)及「金銀分離法」(parting)。此外,硝酸可用來鑒別物品里是否含有金元素,這一古老的方法亦是英語諺語「acid test」的語源,意指用「測試黃金的標準」來測試目標物是否名副其實。
[4B.英文]:Gold,http://en.wikipedia.org/wiki/Gold Gold (pronounced /ˈɡoʊld/ ) is a chemical element with the symbol Au (Latin: aurum) and atomic number 79. It is a highly sought-after precious metal in jewelry, in sculpture, and for ornamentation since the beginning of recorded history. The metal occurs as nuggets or grains in rocks, in veins and in alluvial deposits. Gold is dense, soft, shiny and the most malleable and ductile pure metal known. Pure gold has a bright yellow color and luster traditionally considered attractive, which it maintains without rusting in air or water. It is one of the coinage metals and formed the basis for the gold standard used before the collapse of the Bretton Woods system in 1971. Modern industrial uses include dentistry and electronics, where gold has traditionally found use because of its good resistance to oxidative corrosion. Chemically, gold is a transition metal and can form trivalent and univalent cations upon solvation. At STP it is attacked by aqua regia (a mixture of acids), forming chloroauric acid and by alkaline solutions of cyanide but not by single acids such as hydrochloric, nitric or sulfuric acids. Gold dissolves in mercury, forming amalgam alloys, but does not react with it. Gold is insoluble in nitric acid, which will dissolve silver and base metals, and is the basis of the gold refining technique known as "inquartation and parting". Nitric acid has long been used to confirm the presence of gold in items, and this is the origin of the colloquial term "acid test", referring to a gold standard test for genuine value.
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