пользователей: 30398
предметов: 12406
вопросов: 234839
Конспект-online
РЕГИСТРАЦИЯ ЭКСКУРСИЯ

Text 35 В

 

Text 35 В - раздел Образование, Part One THE PREDICATE Прочтите Текст Про Себя (Контрольное Время Чтения — 3 Минуты). Who Is The Dis...

 
 

   

Прочтите текст про себя (контрольное время чтения — 3 минуты). Who Is the Discoverer of Spectrum Analysis?

The more detailed is the scrutiny of the history of chcmistry, the greater is the number of interesting facts that come to light.

Those accustomed to associate the name of Kirchhoff with the discovery of spectrum analysis will undoubtedly be surprised to learn that in the year 1854, five years prior to the work of Kirchhoff, an unassuming country doctor in a Pennsylvania village definitely demonstrated the possibility of determining various elements by means of their lines in the spcctrum. In fact, this country doctor, David Alter, went further than this.

He pointed out that the method could be used to determine the composition of celestial bodies, thus laying the foundation for the application of the spcctroscopc in astronomy, among the modem sciences. He even called attention to the possibility of detecting impurities in a metal by this method, thus speaking the language of the most up-to-date spcctrographcr.

The only possible claim to priority over Altcr's discovery can be made in behalf of Sir John Hcrschcl, who in 1824 demonstrated the possibility of detecting small quantities of an alkali by its flame spectrum. However, this work was described in an inacccssiblc journal, thus receiving practically no publicity. Unfortunately, it is not unfrcqucntly that this happens. That is why scientists usually seek to publish their papers in prestigious journals: the better the reputation of the journal, the sooner the information it contains comcs to the reader. Furthermore, confuscd by the continual prcscncc of the strong orange lines, later found to be sodium lines. Hcrschcl soon regarded his own discovery as incorrect. The same prevalent sodium lines kept other physicists of that time from realizing that cach element has its characteristic line in the spcctrum.

Alter, however, was not obstructed by this stumbling block. Neither did the lack of scicntiflc instruments discourage him. He ground his own prism and constructed his own apparatus.


19.01.2015; 02:03
хиты: 135
рейтинг:0
Гуманитарные науки
лингвистика и языки
литературный английский
для добавления комментариев необходимо авторизироваться.
  Copyright © 2013-2024. All Rights Reserved. помощь