noun (n)

• an intensely radioactive metallic element that occurs in minute amounts in uranium ores

  sebuah intensely radioaktif unsur logam yang terjadi di menit dalam jumlah ores uranium

  Synonym:
  atomic number 88, ra
  

  source: wordnet30
• An intensely radioactive metallic element found (combined) in minute quantities in pitchblende, and various other uranium minerals. Symbol, Ra; atomic weight, 226.4. Radium was discovered by M. and Mme. Curie, of Paris, who in 1902 separated compounds of it by a tedious process from pitchblende. Its compounds color flames carmine and give a characteristic spectrum. It resembles barium chemically. Radium preparations are remarkable for maintaining themselves at a higher temperature than their surroundings, and for their radiations, which are of three kinds: alpha rays, beta rays, and gamma rays (see these terms). By reason of these rays they ionize gases, affect photographic plates, cause sores on the skin, and produce many other striking effects. Their degree of activity depends on the proportion of radium present, but not on its state of chemical combination or on external conditions.The radioactivity of radium is therefore an atomic property, and is explained as result from a disintegration of the atom. This breaking up occurs in at least seven stages; the successive main products have been studied and are called radium emanation or exradio, radium A, radium B, radium C, etc. (The emanation is a heavy gas, the later products are solids.) These products are regarded as unstable elements, each with an atomic weight a little lower than its predecessor. It is possible that lead is the stable end product. At the same time the light gas helium is formed; it probably consists of the expelled alpha particles. The heat effect mentioned above is ascribed to the impacts of these particles. Radium, in turn, is believed to be formed indirectly by an immeasurably slow disintegration of uranium.

  sebuah intensely radioaktif unsur logam yang ditemukan (gabungan) dalam waktu dalam jumlah pitchblende, dan pelbagai lain mineral uranium. simbol, aku ra/ aku; berat atom, 226. 4. radium ditemukan oleh m. dan ini. curie, dari paris, siapa di 1902 campuran dari itu terpisah oleh proses dari pitchblende membosankan. its senyawa warna api carmine dan memberikan karakteristik spektrum. ini menyerupai kumpulan ahli kimia. radium persiapan luar biasa untuk mempertahankan diri pada aras lebih tinggi daripada suhu sekitar mereka, dan untuk mereka radiasi, iaitu tiga jenis: aku sinar alpha/ aku, aku beta sinar/ aku, dan aku sinar gamma/ aku (melihat perjanjian ini) . lantaran ini sinar mereka ionize gas, mempengaruhi fotografi plat, karena menyakiti pada kulit, dan menghasilkan banyak kesan mencolok. mereka gelar kegiatan tergantung pada kadar dari radium hadir, tapi tidak di negara itu kombinasi kimia atau di luaran kondisi. radiasi dari radium akan menderita jika atom yang properti, dan explai

  source: webster1913