Author Archives: Barrie Mellor

USAF’s X37B Spy Sat – a “mini-Shuttle”

Posted on January 24, 2021 by

One most interesting aerospace project that has managed to keep a relatively low profile is the American X37B reconnaissance spacecraft, as reported by the BBC http://www.bbc.co.uk/news/science-environment-16423881 and described on Wikipedia http://en.wikipedia.org/wiki/X-37B. First going in to service (apparently) in April 2010, … Continue reading →

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FAQ; High Performance Greases and Lubricants

Posted on June 28, 2020 by

When working with aggressive chemicals, the use of greases is often highly restricted (or prohibited) and we are often asked what we use. In working with liquid oxidisers (nitrogen tetroxide, nitric acid and hydrogen fluoride), we have generally found that … Continue reading →

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In terms of Corrosion, what’s the difference between a ‘Passivator’ and an ‘Inhibitor’?

Posted on April 27, 2020 by

Metals are said to be ‘passive’ when they show good corrosion resistance against a specific medium. That is to say that metal A might be passive in liquid 1 but not in liquid 2, whereas metal B might be passive … Continue reading →

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FAQ: optimising the use of Lead Acid Batteries

Posted on January 16, 2016 by

My first response to any question about car batteries (12V lead acid) is that the answer to just about anything you want to know them can be found on one single website; Bill Darden’s most excellent “Car and Deep Cycle … Continue reading →

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Widespread Vitamin D Deficiency in the UK?

Posted on December 2, 2013 by

Vitamin D is essential in a number of biochemical roles in the human body, perhaps the best known is that of being involved in the process in which calcium in taken up for growth and maintenance of bone structure. Vit.D … Continue reading →

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How can you tell if chemical analyses are dependable

Posted on September 11, 2013 by

The question sometimes arises about how a client can be totally confident about the services supplied by a chemical analyst. This is very fair question and one that we ourselves need to consider if we outsource particular tests for which … Continue reading →

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Cleaning of used Electronic Components and other Multi-Metal parts

Posted on March 9, 2013 by

An unusual question arose recently about how to clean old and used electronic components. The particular component  in question was an old socket (base) for a radio valve (tube), which had been put in to an ultrasonic cleaner in water … Continue reading →

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What are the risks involved with using cleaning agents in water-filled cooling and heating systems?

Posted on January 30, 2013 by

Water-filled cooling systems are always subject to some degree of corrosion, and left un-checked, holes can appear in the system allowing the coolant to leak out. Consequently, it is always advisable to use a carefully selected corrosion inhibitor in the … Continue reading →

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How dangerous are the “Green Propellants”?

Posted on January 16, 2013 by

Some time ago we attempted to address the question “How Dangerous are the Hydrazine Fuels” and so it is interesting to consider the same question for the “Green Propellants”. I don’t know if there is any generally accepted definition of … Continue reading →

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Why were some halocarbons solvents banned but some are still in use?

Posted on December 19, 2012 by

The solvents that were banned were the ones that were chemically very stable and survived for very long periods of time in the atmosphere. These materials eventually travelled to the ozone layer and were involved in photochemical reactions which destroyed … Continue reading →

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