Методическая разработка по английскому языку для студентов факультета химии и химической технологии " Simple Chemistry" Алматы 2017
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мет. разработка по химии
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- Beryllium
part solid – частично твердый part liquid –частично жидкий exactly – точно to classify – классифицировать state of matter – состояние вещества definite – определенный shape – форма volume – объем to squeeze – выжимать tube – тюбик, труба to flow – течь (глагол) almost – почти jelly – желе shaving cream – крем для бритья smoke – дым dough – тесто heterogeneous – неоднородный, гетерогенный different – разный foam – дым gas – газ to disperse – растворять , рассеивать liquid – жидкий jelly – желе gel – гель solid – твердый to consist of – состоять из dispersed phase – дисперсная фаза inside – внутри continuous medium – постоянная среда BerylliumBeryllium is a greyish-white metallic chemical element. Beryllium is hard, brittle, lightweight, nonmagnetic element. It is an excellent conductor of heat. It is easily attacked by alkalis or mineral acids with the exception of nitric acid. When we expose it to air at ordinary temperatures, the metal forms an oxide coating that protects it from rust. Beryllium is widely used in alloys because it imparts hardness and strength to copper. Beryllium-copper alloys are used to make electrical contacts, springs, antimagnetic tools and many other devices. Beryllium and many beryllium compounds are toxic. Beryllium metal, which is about two-thirds as heavy as aluminium, is used in the parts of jet engines, missiles, high-speed aircraft, and spacecraft. It is used as an additive in solid rocket fuels and as a reflector to regulate the flow of neutrons in nuclear reactors. Because it is highly transparent to X-rays, the metal is used in X-ray tubes to form a "window" through which the rays are emitted. The most important beryllium compound is beryllium oxide. It is extremely hard, it is strong, and it has high electrical resistance. Beryllium oxide is used as a heat-conducting material in electronic devices. It is used to make high-temperature crucibles. The most important beryllium ore is beryl. Beryl is mined in many parts of the world. Most beryllium is produced by the conversion of the beryllium compounds in the ores to beryllium fluoride, and then the fluoride is reduced with magnesium. Beryllium was discovered in 1798 by the French chemist Louis Vauquelin. The metal was first prepared in pure form in 1828 by the German chemist Friedrich Whler and, independently, the French chemist Antoine Bussy. The symbol of beryllium is Be. Its atomic number is 4. The atomic weight of beryllium is 9.01218. Its melting point is 2,332 F. (1,278 C.). The boiling point of beryllium is 5,378 F. (2,970 C.). Beryllium has specific gravity of 1.85. Beryllium has one stable isotope, Be-9. It belongs to Group II-A of the Periodic Table and has a valence of +2. Vocabulary notes beryllium бериллий greyish-white серовато-белый lightweight легкий to be easily attacked легко подвергаться воздействию alkalis щелочи mineral acids минеральные кислоты an oxide coating оксидное покрытие to protect защищать rust ржавчина hardness твердость to impart придавать beryllium-copper alloys берилиево-медные сплавы electrical contacts электрические контакты springs пружины antimagnetic tools антимагнитные инструменты a part деталь jet engines двигатели реактивных самолетов а missile ракета high-speed aircraft высоко скоростной самолет spacecraft космический корабль an additive добавка solid rocket fuels твердоракетное топливо a reflector отражатель the flow of neutrons поток нейтронов а nuclear reactor ядерный реактор transparent прозрачный X-rays рентгеновские лучи а X-ray tube рентгеновская трубка to emit излучаться a heat-conducting material теплопроводный материал high-temperature crucibles высокотемпературные тигели beryl берилл to mine добывать conversion переработка beryllium fluoride фторид бериллия magnesium магний жүктеу/скачать 422,31 Kb. Достарыңызбен бөлісу:
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