How I Started Programming

19 June 2015

I could have started computer programming much earlier than I actually did. In my final year in high school, one of my teachers asked if I was interested in computer science. To my regret, I answered "No" without thinking.

Haber Process

In our high school physics and chemistry handbook, I had read about the reaction between nitrogen and hydrogen to form ammonia and heat. What was amazing was that the reaction also took place in the opposite direction at the same time, which meant that when heat was applied to ammonia, nitrogen and hydrogen were obtained! The question arose: which reaction would win? Would all of the nitrogen and hydrogen be consumed, leaving only ammonia and heat, or would the opposite happen? The logical answer seemed to be that the faster reaction would win.

The rate of reaction is directly proportional to the concentration of the chemicals. If we start with nitrogen and hydrogen, the forward reaction will initially be faster than the reverse reaction, because we start without ammonia. As the forward reaction progresses, the rate of the reaction lowers because the concentrations of nitrogen and hydrogen lower as they are consumed. As ammonia and heat are formed, their concentrations increase thereby increasing the rate of the reverse reaction. After some time, the rates of the two reactions will be the same, and the amounts of all the chemicals will not change from that point on.

When manufacturing ammonia commercially Haber Process, the intention is to transform as much as possible of the nitrogen and hydrogen into ammonia. Through experimentation it was found that reaction mixtures maintained at different temperatures contain different proportions of nitrogen, hydrogen and ammonia. The lower the temperature, the higher the proportion of ammonia. Unfortunately, the rate of reaction is inversely proportional to temperature. To keep the process economical, a compromise temperature has to be selected.

This type of work I found fascinating, so I decided to study chemical engineering at university.

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How To Change Your Forgotten DokuWiki Password

19 June 2015

If you have forgotten your DokuWiki password, it is possible to set a new password by clicking the Set New Password link on the Login page, then following the instructions. DokuWiki will email a new password to you. But what if the email never arrives?

The DokuWiki user names and passwords are stored in the file path-to-dokuwiki-installation/conf/users.auth.php in the following format:

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