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Irresponsible leaking of information

Dear Reader,

When I read the Guardian this morning it come to my attention that Mike McCaul in the USA has made a statement regarding the explosive which the Manchester bomber used. He stated that the bomb contained acetone peroxide. I think that this was a very bad thing to do as it limits the ability of the British authorities to deal with the criminal or criminal network which is behind this outrage.

I am not sure quite how fast the forensic workers can work, I also wounder how accurate the results which he leaked were. Fox news has claimed that a bomb making workshop was found during a raid recently,

I have to also ask the question of “need to know”, what does the public need to know about the bombing. The public should be told that a bombing has occurred and that the police and other parts of the state are dealing with it. But I would argue that the public do not need to see photographs of the wreckage from the bomb or know technical details of the bomb at this stage. I have to ask the question of what good does it do to tell the public the identity of the explosive.

I can not see a reason or purpose right now, I could understand it coming out during the trial of a bomber. My own view is that the trials of bombers should occur in open court, but during those sections of the trial when the design of the bomb is discussed these sections should be held in camera. My reason is that I would rather that the next generation of bombers do not get an education on bombs by attending (or reading about) a trial where bomb design is considered and discussed.

Now the cat is out of the bag, I see no point in not discussing some aspects of the explosive here. The explosive in question is a rather rare one, it is nitrogen free. Many explosives (TNT, ANFO, Picric acid, RDX, nitroglycerine) contain nitrogen. One of the driving forces for the detonation is the formation of nitrogen gas. A typical explosive contains both a fuel and an oxidant. In the case of TNT the fuel is the methyl group and the aromatic ring while the oxidant is the oxygens in the nitro group.

In the case of the London Tube / Bus bombings and the Manchester concert bombing it appears that the bombers used combinations of an organic fuel and peroxides to build their bomb. In the interests of public safety I will not be giving any details of how to make explosive organic peroxides. I hold the view that the UK is going in the right direction with the law on explosive precursors (Control of Poisons and Explosives Precursors Regulations 2015). This law restricts the sale and possession of chemicals such as hydrogen peroxide. The current limit in the law for hydrogen peroxide without a license is 12 % w/w. This is a rather strong solution compared with what is needed for bleaching hair and other household uses.

If we assume that the density of 12 % hydrogen peroxide is 1 gram per ml, then 1 litre of such a solution will contain 120 grams (3,53 moles) of hydrogen peroxide. This would generate 1.76 moles of oxygen gas if it was decomposed totally which would have a volume of 42 litres. An old fashioned way to express the concentration of hydrogen peroxide is to state the number of litres of oxygen which would be generated by the total decomposition of 1 litre of the hydrogen peroxide solution. When I was a boy I used to buy 30 vol hydrogen peroxide to use in my chemistry experiments which I did in the shed. I had set out to buy 20 vol hydrogen peroxide but I found out that the chemist sold 30 vol hydrogen peroxide instead. I once bought some 50 vol hydrogen peroxide, this would now come under the UK law which I mentioned above.

Manchester bombing

Dear Reader,

It has come to my attention that a bomb was detonated yesterday in Manchester, lets be clear. From the report so far this bombing was an attempt to kill and maim as many people as possible, a cynical and cowardly act aiming at a soft target.

Now right now the UK goverment need to do something, they need to find out if it was a lone criminal or a criminal acting with help from others. Now one of the things which I think is important is to identify the explosive used.

The nature of the explosive will give some clues as to how it was done and the level of help which the bomb maker had. Paul R. Haddad et. al. in Journal of Chromatography A, 2008, 1182, 205–214 explain how to use ion chromatography to identify homemade inorganic explosives such as ANFO, black powder, sugar / chlorate and sugar / perchlorate. In the interests of public safety I will not suggest which of these is most suitable for making bombs. But I can tell you that it is possible from the post detonation fragments to sometimes work out which explosive was used.

For example nitrate anions are characteristic of ANFO (ammonium nitrate / fuel oil) and black powder, while sulfate and thiosulfate are characteristic of black powder. Black powder is the technical term for the “gun powder” made from potassium nitrate, charcoal and sulfur.

From the chlorate / perchlorate explosives it is possible to detect chloride and either chlorate or perchlorate respectively. The information about the nature of the explosive will help the police trace the bomber backwards. In some ways it is similar to an arson investigation. I know that with careful gas chromatography it is possible to identify the brand of petrol used to light a fire. This is a useful thing to know as it is sometimes possible to recover a petrol can from a suspect or obtain CCTV film of them buying petrol shortly before the fire is lit.

Joseph Almog et. al. in Journal of Forensic Sciences, 2007, 52, 1284-1290 does consider the question of how to detect urea nitrate which is another explosive which is sometimes made at home by terrorists. One option for the detection of this explosive is to use para-dimethylamino cinnamalaldehyde, this forms a rather interesting red coloured substance with the explosive. This is reported by Rinat Rozin and Joseph Almog in Forensic Science International, 2011, 208, 25-28.

I downloaded the details of the crystalline solid from the CCDC and here it is. What you should note is that the dimethylamino group is flat, this is an indication that the nitrogen is sp2 hybridised and thus the dimethyl amino group is part of the pi system of the molecule. I think that the nitrogen lone pair is part of the pi system.

molecules of the urea and paradimethylaminocinnamaldehyde thing

Acetone peroxide has also been the subject of some research, this is an explosive which has been used in the past by terror bombers, the explosive is a too sensitive for it to be attractive to the military or the legal explosives industry so when it is found then it is a sign that some “lone wolf” terrorist or other person who can not gain access to “normal” explosives such as TNT has been going about their horrid activities. Likewise I think that the use of urea nitrate and the fuel / chlorate (and perchlorate) mixtures suggests that it is an explosive made by the bomber themselves (or by someone close to them).

Black powder and ANFO are not so clear these are explosives which have legal purposes which can also be made illegally. Black powder is used in fireworks and also sometimes in firearms. Already one group of terrorists (Boston marathon bombers) used fireworks as their source of explosives.

The use of nitroarene and nitroamine explosives such as TNT / picric acid and RDX would suggest to me that the bomber had outside help in the form of someone who could supply explosives such as Semtex to them. It is not uncommon for some trace of the explosive to survive the detonation event so even if a readymade high explosive was used it may be possible to work out what the explosive was. What this means to society is that even while the bomber is dead it maybe possible to work out from physical evidence some clues to what happened and where the bomb came from.

Forgive what ?

Dear Reader,

It has come to my attention that the Swedish prosecutors have chosen to give up on the Julian Assange case. Now Julian is upset and angry, he is saying that he will not “forgive and forget”. I have to ask the question what has he to “forgive”.

My understanding of the word “forgive” that it is a verb (action word) which means to decide that someone or something which has done some wrong to you should not be punished or pursued for that wrong. Instead you have chosen to allow to let the thing go. For example if you catch your child eating your slice of cake out of the fridge, rather than holding it against them for the rest of time you might (and I hope you will) choose to forgive them for this act of theft instead of chasing them for it for the rest of time !

So my reasoning is that to be able to forgive you have to be the wronged party, I have to ask the question of “how has Julian been wronged”, and “who has wronged him ?”.

He complains about having his name “slandered”, being detained for seven years and having his family life disrupted. Now I will go through these points one by one.

Now Mr Assange has been accused of a serious crime which is quite rightly repulsive to decent people, I am not able to make a judgement in a legal sense here as legal judgement should be made in a real court with a real judge and not in the “court of public opinion”. Thank goodness we do not have trial by media !

But if Julian had wanted to he could have gone to Göteborg or Stockholm to get the matter over with. If he had been so sure that the case against him was a tissue of lies then he could have made steps to clear his name, I am sure that in terms of reputational harm that his cooperation with the police / legal system would have counted in his favor. He could have painted himself as the sad victim of a malicious accusation, rather than a person who attempts to avoid justice.

Mr Assange has been involved in a thing called Wikileaks, and he wants openness in goverment. Now a intellectual hero of mine (Louis Dembitz Brandeis) who was a Judge in the USA commented

Publicity is justly commended as a remedy for social and industrial diseases. Sunlight is said to be the best of disinfectants

Now I am sure that it would be hard for Julian to disagree with the idea that a goverment official accused of some crime should cooperate with the criminal justice system and either clear his / her name or accept whatever fate (sentence) they get if they get rightly convicted. Consider Jonathan Aitken, he was an immoral man who lied in court and he was sent to jail. But he did clean up his life in jail. Equally it is hard for anyone to argue that Jeffrey Archer should have been allowed to escape justice.

I am sure that if Jeffrey Archer had run off and hidden someone rather than going to court that Wikileaks would have been unlikely to have approved his action. I reason that if Julian is so keen on openness that he should have applied the principle of openness to himself and cooperated fully with the legal system.

The next thing which he complains about is his “detention”, some UN body (a rather misguided one) has stated that “Mr. Assange had been subjected to different forms of deprivation of liberty: initial detention in Wandsworth Prison in London, followed by house arrest and then confinement at the Ecuadorean Embassy

The “confinement at the Ecuadorean Embassy” was not ordered by either the Swedish or UK state, it was self imposed.  hit the nail on the head perfectly when he pointed out that Mr Assange has hidden himself away from justice rather than having been confined by the state.

Maybe by the same logic of most of the panel I have also kidnapped myself by going for a walk, a walk I wanted to go for. To my mind the logic of the UN panel is deeply wrong and twisted. It is interesting that one member of the panel (who disgreed with the others) Vladimir Tochilovsky who is a law academic quite rightly expressed the view that “Mr Assange’s situation amounted to “self-confinement” – and was therefore outside the panel’s remit” (Summary on the Telegraph‘s site).  It is at the end of the opinion issued by the UN panel. For anyone who wants to read it here it is

“Individual dissenting opinion of WGAD member Vladimir Tochilovsky

  1. The adopted Opinion raises serious question as to the scope of the mandate of the Working Group.
  2. It is assumed in the Opinion that Mr. Assange has been detained in the Embassy of Ecuador in London by the authorities of the United Kingdom. In particular, it is stated that his stay in the Embassy constitutes “a state of an arbitrary deprivation of liberty.”
  3. In fact, Mr. Assange fled the bail in June 2012 and since then stays at the premises of the Embassy using them as a safe haven to evade arrest. Indeed, fugitives are often self-confined within the places where they evade arrest and detention. This could be some premises, as in Mr. Assange’s situation, or the territory of the State that does not recognise the arrest warrant. However, these territories and premises of self-confinement cannot be considered as places of detention for the purposes of the mandate of the Working Group.
  4. In regard to the house arrest of Mr. Assange in 2011-2012, it was previously emphasised by the Working Group that where the person is allowed to leave the residence (as in Mr. Assange’s case), it is “a form of restriction of liberty rather than deprivation of liberty, measure which would then lie outside the Group’s competence” (E/CN.4/1998/44, para. 41(e)). Mr. Assange was allowed to leave the mansion where he was supposed to reside while litigating against extradition in the courts of the United Kingdom. As soon as his last application was dismissed by the Supreme Court in June 2012, Mr. Assange fled the bail.
  5. The mandate of the Working Group is not without limits. By definition, the Working Group is not competent to consider situations that do not involve deprivation of liberty. For the same reason, issues related to the fugitives’ self-confinement, such as asylum and extradition, do not fall into the mandate of the Working Group (see, for instance, E/CN.4/1999/63, para. 67).
  6. That is not to say that the complaints of Mr. Assange could not have been considered. There exist the appropriate UN human rights treaty bodies and the European Court of Human Rights that do have mandate to examine such complaints regardless whether they involve deprivation of liberty or not.
  7. Incidentally, any further application of Mr. Assange may now be declared inadmissible in an appropriate UN body or ECtHR on the matters that have been considered by the Working Group. In this regard, one may refer to the ECtHR decision in Peraldi v. France (2096/05) and the reservation of Sweden to the First Optional Protocol to the ICCPR.
  8. For these reasons, I dissent.”

The comments about his family life are rather silly, Mr Assange choose to isolate himself from his family. I am sure that if he was sent to a Swedish prison that he would be allowed to be visited by his family.

Synthetic cannabinoids vs PCP

Dear Reader,

Sadly it has come to my attention that a couple in the USA rather than having the good sense to either go home to a bedroom, rent a hotel room or hide inside something like Ford transit van decided to have sex in the car park of a restaurant. Secondly it appears that both of them may well have been high on something which lower inhibitions. The “young lady” in a rather unladylike manner did some things which I will not discuss further. While her lover was reported to have blank stares and to have made animal noises (<sarcasm>Oh how romantic !</sarcasm>).

The Daily mail got things wrong by commenting that the man was arrested for having PCP on him stating that it is synthetic marijuana. Trust me it is not ! PCP is a rather nasty drug which is phencyclidine (Angel dust) which is a dissociative hallucinogen.

There are some very different molecules which are very different to PCP such as JWH-018 which bind to the same receptor as THC does. These are what are often sold as “synthetic marijuana”. I regard them as a very nasty class of drugs, if you are stupid enough to consider taking one of them then I suggest you watch this US Navy film about the story of the sailor who takes spice.

While those twits who are considering doing “bath salts” should watch this one !

As the military doctors in the film saym “its not worth it”.


Dear Reader,

It has come to my attention that an accident has occurred at Hanford, for those of you who do not know Hanford is an early nuclear site in the USA in Washington. At this site plutonium was produced, the plutonium used in world war two for nuclear bombs was made there inside the reactors.

I will not pretend that the site is in great condition, there are some serious problems with the way that radioactive waste was stored on the site. What happened was in the early days that neutron irradiated uranium was dissolved in nitric acid. This fuel solution was then processed to recover the uranium.

The first process used was the bismuth phosphate process which I regard as a very dirty process which generates a vast amount of secondary waste. The mixture of plutonium and everything else in a mixture of nitric and sulfuric acids had the oxidation state of the plutonium adjusted with nitrous acid.

Then the plutonium was precipitated using bismuth phosphate, this process separated the plutonium from the uranium and the vast majority of the fission products. The waste solution from this process was then made alkaline with sodium hydroxide before being placed in large steel tanks. The problem with the Hanford site is that it has many different radioactive waste stores and different buildings, so it is not a simple site. But I think that the single skinned tanks containing the alkaline waste are the worst thing on the site.

It is not clear exactly what has happened at the site today, but I think that the worst case accident could never be as bad as Chernobyl. The majority of the radioactivity is inside the tanks. There is a program of tank emptying, the contents of the tanks are being removed and then conditioned to reduce the threat that it poses. A good review of the site can be seen here.

I know that in the Soviet Union that a high level waste tank at Mayak exploded (Kyshtym accident). Here ammonium nitrate and acetates are thought to have reacted violently in the waste store thus ejecting waste from the tank. At Hanford ammonium nitrate and acetates were not present in the waste. Thus the waste in the tanks is more chemically stable. The waste does form some hydrogen as a result of the radiolysis of water. But the hydrogen is a less scary fuel than the ammonium nitrate / acetates.


This should have been in Camera

Dear Reader,

The recklessness of some people drives me to a new level of distraction, I have chosen to not name the case or the newspaper in this blog article but I will tell you the story. Some irksome pest tries to build a homemade bomb, this homemade special fails. Then the news paper reports the court case explaining how and why it failed to detonate.

What I think is that any public discussion of a failed bomb is an educational moment which we are better off without. The problem I see is that building any complex gadget is hard when you have to make everything yourself. Having had an interest in electronics I can tell you that many gadgets have taken a lot of development work to get to the level which the public now considers “normal”.

Also having been in the business of developing chemical processes, I can tell you that the creation of a process (or even just the implementation of an existing process)  can take a lot of work. One of the things which always makes it more easy is a knowledge of how someone else did it successfully and an understanding of what went wrong the last time.

The knowledge that a particular method or material is unsuitable for a task is a great help, it saves a lot of time and effort. The reason is that a person will not go chasing after something which does not work. By publishing a truthful discussion of how a bomber failed the newspapers are helping the next generation of bombers by improving their knowledge.

Some years ago I was told something interesting at the ITU in Germany, they commented that a large fraction of illicit plutonium samples which have been intercepted contain red materials. They believe that the Soviet intelligence services leaked some misinformation about “red mercury”. The story is that “red mercury” greatly increases the ease of building a working nuclear weapon.

By releasing this crazy story about a spoof material, the Soviets were attempting to  waste the time and efforts of would-be nuclear terrorists. By encouraging them to chase a false lead it would have helped world peace. The reason is that every hour and dollar a terrorist spends looking for ways to obtain and use this material is a hour or dollar which they could not use one something which is more likely to provide them with a weapon. Very clever I think !

I have to ask why the facts of this type of case be discussed in public, and why the newspaper staff did not have the sense not to self censor what they published.

Hamburg airport

Dear Reader,

It has come to my attention that a irritant gas or aerosol has been released in the airport today causing the site to be closed down. One reports suggest that a pepper spray was discharged by “some clown” into the ventilation system. Some of my readers might want to know what is in pepper spray, these sprays are typically capsaicin and the other active chemicals in chill peppers in a solvent with a propellant to allow it to be discharged as a spray.

Capsaicin is quite a simple compound, here is a picture of a molecule of it.


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