The Second Version

31/01/07

Greenhouse Effect, Limited

The "greenhouse effect" is the phenomenon that lies at the heart of the supposed AGW, and it begins with absorption of part of the infrared radiation emitted by Earth by some chemicals in the atmosphere, of which carbon dioxide is the most famous.

This particular instance of radiation absorption is not physically different from the light absorption used by spectroscopic thecniques to measure the concentration of a chemical compound in a given solution. Absorption is described by Beer-Lambert's law, which has the form:

log(I/I0) = -c[J]l

or, as exponential:

I/I0 = 10-c[J]l

Above, I is the intensity of transmitted light and I0 the intensity of incident light; c a proportionality constant specific for each analyte; [J] the molar concentration of the analyte and l the length of the optical path. An example plot, using c=0.5 and l=1 can be seen here too. As explained in the text, the concentration increase from 0 to 0.5 (mol/L) produces a bigger transmittance reduction than concentration going from 10 to 20.

This equation tells us that the relationship between transmittance (the ratio at the left side) and analyte concentration is non-linear, and that transmittance tends to zero for increasing concentration. What happens in practice is that when transmittance drops to zero (all light is absorbed), further increase of the analyte concentration does not produce any change - this happens sometimes when preparing samples for IR spectroscopy: if the analyte concentration is too high, the strongest bands of the spectrum will become saturated with loss of details and information.

Going back to the greenhouse effect, what happens in case of doubling atmospheric CO2 concentration depends from in which region the doubling occurs: if it is at low concentration, the effect will be great; but near the saturation point, it will be small.

I expect climate models to take this simple issue into account - though it is a bit difficult to know where exactly is the current status of atmosphere regarding transmittance. But this is a problem that only a few laypeople know, while it is important in the AGW debate.

Update 20/02: I don't know why I forgot to include a CO2 absorption spectrum. So, here they are. The figure is carbon dioxide's absorption spectrum in laboratory conditions, while here is the actual IR emission spectrum of Earth.

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The Winner Is...

This new blog thingy just had its 1000th visitor. Someone from Tor Sapienza*, Lazio, Italy. Who didn't even stop to say hello, the sod...

*So says Sitemeter; I've never heard of that town before.

By the way, the term "Timewastotoxin" comes from this post on this chemistry blog. Credits to the author.

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29/01/07

Due Motivi Contro i PACS

Ci sono due motivi principali per cui sono contrario all'introdurre i PACS - ovvero il riconoscimento delle coppie di fatto - nell'ordinamento italiano.

Per cominciare, ritengo che la famiglia tradizionale sia un fondamento migliore per una società forte e sicura della propria identità - mi sembra che la storia sia piena di esempi del genere. Migliore di famiglie allargate, omosessuali e qaunt'altro. Quindi, ritengo sia opportuno che lo stato e la società intera privilegino la famiglia tradizionale. So che questa posizione è simile a quella della CEI, ma le mie motivazioni sono pragmatiche invece che religiose. (Mi rendo anche conto che privilegiare la famiglia tradizionale non comporta necessariamente negare il roconoscimento alle unioni di fatto).

Però c'è un secondo motivo per la mia opposizione, più libertario del precedente. Voglio che rimangano (anzi, che si ingrandiscano) degli spazi di Libertà (cosa ben diversa dagli spazi di libertà di cui cianciano autonomi assortiti) nei quali persone sufficientemente mature e consenzienti possano unirsi nel tipo di relazione che preferiscono senza dover per forza rientrare in categorie definite e regolamentate dallo stato. Ora abbiamo il matrimonio civile e religioso; qualcuno vuole i PACS... la prossima cosa sarà, la registrazione per gli scambisti? Gli "Accordi di relazione amorosa a breve termine (aperta o chiusa)" al posto delle storie adolescenziali?

Per la corrente classe politica (il centro-destra è solo un poco migliore) sembra che la soluzione sia sempre più stato, più leggi e regolamenti in ogni campo. Ma non è così: la soluzione invece è sempre più Libertà.

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26/01/07

Seeds of Life

How did life on Earth start?
If we exclude the belief in divine creation*, that is an utterly fascinating question with huge implications - whatever the answer.

According to some views, life may have been initiated by aminoacids and other organic molecules that formed in space and were carried to our planet by comets and asteroids - despite the high-energy impacts, there are definite chances that a relevant fraction of these molecules can survive. And then (this is in great part my own view) the compounds thus arrived would act as sort of templates, directing the subsequent developments of chemical systems on Earth. And starting the long, hard slog of life and then evolution. The template effect isn't so peregrine from the standpoint of supramolecular chemistry and catalysis.

In other words, there would be seeds of life out in the deep space, which will start organic life if they reach a suitable planet (or another body, eventually).

Now, the composition of interstellar dust clouds, as far as I know, does not change much from one point to the other of our galaxy at least. This has an interesting implication: all life in the Milky Way at least may very well be based not only on carbon, but also on very similar building blocks - aminoacids. There is still room for a huge deal of variation, but all living things in this case would share a good deal of basic biochemistry.

Another interesting question is, what does influence the development of these seeds? Is it more a matter of local conditions, or their inherent properties? If the latter influence is dominant, all life may be not too dissimilar from the Earthly version.

However, there is no way to tell unless we either find genuine xenotic organism - or create some new lifeform from scratch. Either way, it is a mess. The confirmation that macroscopic xenotic organisms do exist would cause a huge cultural shock in theists and atheists alike; while the creation of new life from scratch poses serious ethical questions.

But boy, this stuff keep the wheels in my head spinning!

* Creation is not so fascinating for me because once it is said "God wanted thus for His own inscrutable reasons", the debate is pretty much over.

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Tempo di Agire

Si sta discutendo molto sui blog italiani del disgraziato provvedimento del governo che prevede di re-introdurre ed inasprire le pene per reati di opinione i reati di apologia di crimini contro l'umanità e diffusione e diffusione di idee fondate sulla superiorità o sull’odio razziale o etnico - decreto abilmente mascherato da azione contro l'antisemitismo.

Non ci vuole un genio per capire che con l'arbitrarietà imperante nella magistratura italiana qualunque idea che devii da una stretta ortodossia possa essere inclusa nelle categorie precedenti. Come succede spesso in Italia, nella gran parte dei casi nulla accadrà, ma chi finirà nel mirino delle persone sbagliate (per esempio, estremisti islamici o giudici sinistrati) vedrà la sua vita rovinata.

E' buono e giusto discutere di questi argomenti nei nostri angoli, ma non basta. Bisogna fare pressione diretta sui politici direttamente coinvolti (lo so, nemmeno questo cambierà il mondo, ma almeno è un tentativo).

Per questo chiamo a raccolta i miei amici, colleghi ed alleati di Il Castello, The Right Nation, NeoLib ed anche i pochi rimasti a Tocqueville per organizzare una campagna di protesta diretta verso Romano Prodi, Clemente Mastella e deputati e senatori perchè non approvino questo obbrobrio. Non solo, perchè anche si impegnino ad eliminare le restrizioni già presenti alla libertà di espressione.

Qualche sito internet:

Presidenza del Consiglio

Ministero della Giustizia

Senatori della Repubblica

Scrivi al tuo Deputato

E per finire, la lista dei parlamentari dell'Emilia-Romagna.

CAMERA
Ulivo: Romano Prodi, Pier Luigi Bersani, Pierluigi Castagnetti, Maurizio Migliavacca, Dario Franceschini, Katia Zanotti, Ivano Miglioli, Donata Lenzi, Maino Marchi, Antonio La Forgia, Gabriele Albonetti, Raffaello De Brasi, Giuliano Pedulli, Sergio Gentili, Rosella Ottone, Carmen Motta, Andrea Papini, Manuela Ghizzoni, Giuseppe Chicci, Sandro Brandolini, Ermanno Vichi. Primo dei non eletti: Alfiero Grandi.
Partito della Rifondazione Comunista: Fausto Bertinotti, Francesco Ferrara detto Ciccio, Titti De Simone. Primo dei non eletti: Donatella Mungo.
Comunisti Italiani: Oliviero Diliberto. Primo dei non eletti Roberto Soffritti.
Di Pietro Italia dei Valori: Antonio Di Pietro. Primo dei non eletti: Giuseppe Astore. Federazione dei Verdi: Alfonso Pecoraro Scanio. Primo dei non eletti: Paolo Cento.
La Rosa nel Pugno: Emma Bonino. Primo dei non eletti: Enrico Boselli.
Forza Italia: Silvio Berlusconi, Giulio Tremonti, Isabella Bertolini, Francesco Nucara, Jole Santelli, Fabio Garagnani, Giorgio Lainati. Primo dei non eletti: Sergio Pizzolante. Secondo dei non eletti: Patrizia Tangheroni Paoletti.
Alleanza Nazionale: Gianfranco Fini, Enzo Raisi, Tommaso Foti, Maria Ida Germontani. Primo dei non eletti: Francesco Biava.
Lega Nord: Umberto Bossi, Angelo Alessandri. Primo dei non eletti Gianluca Pini.
Udc: Pier Ferdinando Casini, Carlo Giovanardi. Primo dei non eletti: Gian Luca Galletti.

SENATO
Democratici di Sinistra: Sergio Zavoli, Vidmer Mercatali, Walter Vitali, Giuliano Barbolini, Andrea Manzella, Federico Enriques, Leana Pignedoli. Primo dei non eletti: Alfredo Sandri.
Dl-Margherita: Roberto Pinza, Albertina Soliani. Primo dei non eletti: Luca Marcora.
Partito della Rifondazione Comunista: Claudio Grassi, Martino Albonetti. Primo dei non eletti: Pier Giorgio Poeta.
Insieme con l'Unione: Armando Cossutta. Primo dei non eletti Sauro Turroni.
Forza Italia: Marcello Pera, Pietro Lunardi, Giampaolo Bettamio, Laura Bianconi. Primo dei non eletti: Vittorio Guasti.
Allenza Nazionale: Filippo Berselli, Alberto Balboni, Stefano Morselli. Primo dei non eletti: Claudia Rubini.
Udc: Francesco D'Onofrio. Primo dei non eletti: Mauro Libé.
Lega Nord: Roberto Calderoli. Primo dei non eletti: Massimo Polledri.

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24/01/07

The Conservation Dogma

If you want to read about an interesting alternat theory regarding recent climate change, and an interesting debate on the issue, pay a visit to Winds of Change. A commenter there asked a couple of fundamental question, that everyone interested in the climate change controversy should ask too:
Is there an optimal temperature (or range of) for the planet?

If so, what is it and why?
This is the pragmatic approach that ought to be taken, but it clashes with the dogmatic approach of a large fraction of environmentalists.

Their dogma, that I shall henceforth dub "Conservation Dogma" is that humans should cause minimal or even better no change to the environment and ecosystems in which they are living. Nature must instead be conserved.

I am using the term change for a precise reason: it is neutral. Change can be either positive or negative and the dogma is opposition to change regardless - while reasonable people can agree on the fact that negative change (say, severe pollution) is not auspicable.

That this position is dogmatic can be understood asking to most environmentalist why we shouldn't modify our ecosystem, or should do it within extremely narrow limits. Most of times, their reply is along the lines of Just Because, or a circular argument. Some may add that we shouldn't leave a worn, depauperated Earth to our descendants, but also this is only a partly satisfying answer. Because if in one century or two Earth will miss the Spotted Owl and a few species of tundra lichens, will it really be such a worse place? In fact, most of the humans won't even notice.

Now, my readers should not think that I rejoice contemplating the destruction of Nature. In actual fact, I enjoy being in nearly-uncontaminated places at least for a while; and considering that a lot of my fellow men manifest the same appreciation, I conclude that there must be reasons deeply seated in our human essence for such behaviour. A caffeine high makes me write definitely better.

But in the balance, I have a higher considerations for humans than other lifeforms. If the well-being of millions in the developing world cannot be achieved without the sacrifice of, say, dolphins, I'll throw flowers in the ocean, donate a sum to the Dolphin's Memorial Fund and maybe mutter somber words, but won't see myself as a novel Adolf Eichmann.

One reason for the Conservation Dogma is sheer ignorance. Nature is seen as a static - or, in engineer's speak, steady-state - system in which not much changes if not as the result of an external perturbation. But this view is utterly wrong. In fact, all material objects have to change and finally decay at some point. Species evolve, prosper and then disappear, leaving descendants or not. Mountains rise only to be eroded away; seas and lakes are filled - by the same materials the once made mountains - or squeezed dry between mastodontic pieces of rock floating around on the Earth's mantle. Climate mutates from hot to cold, dry to wet. Stability is unnatural, while change is certain and perturbations come from within the system - maybe from our Sun, which is far away but must not be forgotten: a simple burp of its immane nuclear furnace, barely worth noticing in astronomical terms, could wipe out most of the life from this planet.

But there is a more worrisome strain of anti-humanity in the Conservation Dogma. This considers human as the Great Perturbation, as an aberration of Nature that will ultimately cause Her own demise. From this base, conservation is only the beginning: the final objective is extinction of Homo Sapiens, or at least its reduction to sparute tribes unable to build anything more advanced than mud huts, if that. I do not sincerely know the genesis of such a position, but I firmly hold the opinion that it is a perverted aberration. It goes against the commandment that seems to be written in anything from the simplest genetic codes upwards: SURVIVE! And as a corollary, prosper, any way you can. Be stubborn, be curious, leave no alley unexplored and no stone unturned.

We humans arrived at our civilization's achievements because we were worth more than the chimps, whose highest achievement remains sticking a twig in an ants' nest. Call me when you'll see them chipping stones into some shape that did not occur naturally. We had a relatively frail body, but an astonishing mind, and we put it to work. If the first tiger slaughtered by lance-armed early humans could speak, its last words would be along the lines of "Oh shit! These little bastards are packing!".

I totally reject tthe idea that humans are unnatural. Though, I am aware of the fact that we broke the rules of an ancient game of mutation, selection and survival and we should spend some time pondering that. Because being able to do many amazing deeds does not mean we are omnipotent and can escape the consequences of wrong decisions. But the game will nevertheless continue with the new rules, and there will again be winners and losers.

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Stormy Night

It is a night of gale in Parma. A strong south-easterly wind is blowing over the city; it was 17 knots at 21:00Z, but now it has to be way stronger. Nothing to be worried about - actually, a stormy night makes me appreciate my cozy bed even more. If only there wasn't a tall construction crane standing just across the courtyard, it would be perfect (but the wind isn't pushing it towards my condo, at least).

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22/01/07

Differenza Nella Violenza

Un commento che ho lasciato sul blog di Aribandus mi ha poi ispirato una breve discussione di approfondimento.

Si, quello che voglio fare è opporre la violenza protettiva dei cittadini onesti alla violenza predatoria dei criminali.

Ho trovato una definizione chiara, concisa, e spero efficace dei due fenomeni:

Violenza predatoria è quella intesa a violare i diritti altrui.
Violenza protettiva è quella intesa a proteggere i propri diritti.

Segue della definizione che non c'è equivalenza morale fra le due. La violenza predatoria è male; quella protettiva è neutra se non bene.

Aggiornamento 23/01: Mi sembra che quello che scrissi alcuni mesi fa sulla differenza fra autodifesa e giustizia sia pertinente.

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19/01/07

You Gotta Try for Yourself

Some time ago I accidentally bought a too wide (at the waist) pair of trousers... since then I have also lost some weight, so now those trousers are positively baggy, to the point I need to wear them with a belt.

But today, for a change, I decided to wear them (at home, mind you) beltless, low-riding gangsta-style. Never again; it's one of the most uncomfortable and impractical solutions one can find.

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18/01/07

Scam Mail Warning

I received an e-mail saying:
British Petroleum (BP)
PLCHuman Resource Department
1 St James's Square London,SW1Y 4PD
TEL: +44-703-184-1852
Ref: 01/007/HRD/BPPLC
Date:15/01/2007



JOB ALERT!

Could you be the right person for this job offer? What if our judgement was wrong? You might want to try your hands on it but unfortunately we are only looking for professionals with expectional expertise, highly spirited individuals who are ready to take up a rewarding challenges in the oil and gas industry.

BP, a well established and reputable oil/gas company with rapidly growing wide network of outlets around the world, seeks to attract resourceful individuals craving for a refreshing opportunity yet characteristically possesses the skill and uprightness to excellently deliver amidst limited assistance.

JOB LOCATIONS
- South-Africa
- Europe
- U.S.A

METHOD OF APPLICATION
- All interested candidates should reply via mail with updated Resumes (CV).- Interested applicants must specify job location
- Only applicants who possess the required qualifications will be short-listed whence consequently contacted.

All Resumes should be fowarded to: bp_recruitingsection@yahoo.co.uk
*********************************************
HR
DepartmentRecruitment
SectionLondon(UK)
*********************************************
That comes complete of a nice BP logo in the top left corner. Well, I've gone through the real BP recruitment process, and it's not like that. Especially, the yahoo.co.uk e-mail address should be a giveaway. Applications should instead be submitted online at this address only; there is no other legit way.

What may happen to those sending their resume to the fake BP, I don't know. But I can speculate that at least their personal information will be used to target them with all sorts of spam. In the worst case, their identity may be stolen. So beware. If I am wrong, please serve me a succulent roast crow.

By the way, forging communications in this fashin may very well be a legal offense. But I'm sure BP can take care of its own legal affairs by itself.

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16/01/07

Mattino al Poligono

Sabato scorso finalmente ho deciso di intraprendere l'iter pratico e burocratico per ottenere un porto d'armi. La prima tappa quindi è il poligono di tiro: mi sono presentato lì alle nove di mattina con la documentazione richiesta (certificato medico per la pratica sportiva non agonistica, 2 foto tessera, documento d'identità) e dopo aver firmato un modulo d'iscrizione sono stato ammesso alla prova d'armi.

Questa prova consiste di una lezione teorica sulle norme di sicurezza nell'uso delle armi da fuoco (l'argomento principale), quindi i principi balistici e di funzionamento delle armi; elementi della legislazione e per finire techniche di tiro al bersaglio. La lezione non ha detto molto che non sapessi già, ma è stata comunque abbastanza ben fatta (tranne certe imprecisioni riguardanti la caccia, ma le possiamo perdonare). Eravamo una decina di allievi, tutti uomini tranne una donna che poi ha scelto di sparare con la carabina.

Dopo la lezione, è arrivata la prte più divertente: tiro al bersaglio! All'armeria siamo stati dotati di una scatola da 50 munizioni .22 LR, un bersaglio e tappi per le orecchie (niente è gratis, però). Quindi abbiamo raggiunto il tunnel di tiro per attaccare i bersagli ai supporti - mentre gli istruttori continuavano a spiegare le norme di sicurezza e comportamento del poligono - per finalmente raggiungere la linea di tiro.

Io avevo scelto pistola, ed infatti ho trovato sul bancone una Beretta 89 nella sua valigetta. Sempre seguendo le istruzioni del direttore di tiro ed istruttore, ho caricato i colpi nel caricatore, caricato ed armato la pistola per iniziare a sparare contro il bersaglio a 25 metri di distanza.

La sensazione di una pistola che spara nella propria mano è unica ed inaspettata. Il rinculo di una .22 da tiro è minimo, ed i tappi proteggono dal rumore... ma il tutto si sente e si vede bene. Ho sparato i primi 25 colpi, a serie da 5, nella posizione ad un braccio solo - sempre sotto l'occhio viglie dell'istruttore. poi con il canocchiale ho controllato i risultati: anche se i miei colpi erano quasi tutti dentro il bersaglio (non nel cerchio nero... magari!), erano anche finiti sparpagliati in giro. Ero un po' nervoso per essere la prima volta che sparavo... poi era un giorno freddo ed umido, ed avevo bevuto una lattina fredda all'uscita della lezione, per cui avev o i brividi sulla linea di tiro.

Comunque, per gli altri 25 colpi ho iniziato a prendere confidenza con la pistola, a concentrarmi meglio sull'applicazione della tecnica corretta, ed i miei proiettili hanno iniziato a raggrupparsi, anche se un po' sotto al nero del bersaglio. Alla fine, ho messo 45 colpi nel bersaglio, e così ho superato brillantemente la prova (che ne richiede almeno 30). Meno divertente è stato quando alla fine ho dovuto sborsare gli oltre cento euro per la prova d'armi e l'iscrizione al poligono del 2007, ma non si può avere niente per niente.

Il mio programma futuro ora prevede ancora qualche settimana di pratica con la .22, fino ad ottenere buone rosate ed un comportamento fluido, per poi provare un calibro maggiore (9mm, direi).

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15/01/07

Useless Research

Via Steven, a ground-breaking revelation:
Why Do Teens Have Sex? For Intimacy, Social Status, Study Says
But steven also offers a novel, genius insight:
I think they have sex because they're horny.
There's something telling me that he just may be right...

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14/01/07

Soppressione di Libertà

Abr ci informa di un fatto decisamente inquietante: con una norma contenuta nell'ultima Finanziaria, il governo ha subdolamente reso illegale la riproduzione anche parziale di articoli di giornali e riviste. Cioè, anche il quotare tanto diffuso fra i blogger è ora formalmente illegale.

Eh si, la libertà. Facile parlarne (a sproposito), ma molto più difficile praticarla e mantenerla. Per difenderci da noi stessi e dall'umana stupidità; per proteggerei nostri bambini e l'ambiente; per non togliere il pane di bocca dai poveri editori di giornali che tirano decine di migliaia di copie al giorno; tutte le scuse sono buone per ridurre la libertà personale un pezzetto alla volta. Finchè un giorno i cittadini non saranno assolutamente schivi, ma - e questa è l'invenzione geniale del tranzismo e socialdemocrazia europea - non di un un singolo dittatore, ma di una vasta burocrazia senza nome e senza volto. E' facile pensare di abbattere ed uccidere un solo tiranno, ma più difficile pensare di abbattere migliaia di burocrati senza identità ben definita.

Servono molte più munizioni.


Immagine di Kim DuToit

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12/01/07

Culture of Safety

Today I had a job interview with a big multinational chemical corporation (yes, one of those polluting Gaia and poisoning children) - which I cannot name for confidentiality reasons. Among many other things of no relevance, one of the interviewers told me how an accident occurred at another facility of the same company.

Parasite reactions which had never been observed before occurred within the storage tank of an intermediate product, producing heat. Even if the molar heat of reaction was small, the quantity of material in the tank was considerable; the thermal insulation good, and over a long time (weeks), the temperature increased to dangerous levels. There apparently were other minor equipment problems, and the whole chain of events resulted in an explosion and subsequent fire. Anyway, only three workers were mildly intoxicated by the fumes.

How did all this became clear? Because the company conducted an internal in-depth investigation on the incident: believe it or not, but corporations don't really like it when their plants blow up. Anyway, the lessons learned are being applied, and new processes are carefully examined beforehand against the possibility of these parasite reactions.
All this is possible because this corporation does care about safety in the first place, and has policies and procedures in place (like other companies do, of course).

The most infamous incident of the chemical industry, instead, occurred at Bhopal with catastrophic consequences (thousands deaths, among them) and it was caused by a long string of events - some imputable to the management, but some more insidious and related to the local culture. Corporations do provide (or at least are supposed to) proper training to the workers, but I'm not sure it can override a worldview formed in years by family, peers, schools, churches/mosques and all that. According to some sources, the prevalent local culture at Bhopal (a mainly Muslim area) was very fatalistic: if Allah wills, the plant will work no matter what, but if He doesn't want, the plant will fail despite any human effort.

I've seen personally, and heard many stories of people who learnt to do a job the old way, and are not going to change even if there are new and better ways of doing the job. I think that the proper safety culture can only be instilled in a workforce that is already receptive to it; otherwise safety will always remain a secondary concern. workers will behave until they are closely supervised, but revert to the old habits as soon as they can. And yes, I have firsthand experience of that too - fortunately, not in safety-critical situations.

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11/01/07

Superconductivity, Where Art Thou?

Superconductivity is the phenomenon in which a material, below a certain carachteristic temperature will allow an electrical current to pass with virtually zero resistance - this also mean the current density in such a material can be very high. In-depth details are available here, because I don't want to concentrate on that subject now.

Superconductors are very interesting materials in many fields. Not only they can dramatically cut electricity transmission losses, but they also can be used to build transformers, electromagnets, motors and generators much more powerful, efficient, small and light than current ones. And those nifty quantum devices known as SQUIDs.

Of course, there also are military applications, in the form of electromagnetic guns and all-electrical ships, and possibly EMP weapons. In theory, it is possible to store electricity for long periods as a current circulating in a superconductor ring or loop: such a device could resolve energy storage problems.

Superconductors wires are already used in some practical applications - mainly, NMR machines but also short-range power transmission lines. The main limit is the cooling needs: even the best superconductors have transition temperatures of 138 - 150 K, which require liquid nitrogen cooling. Liquid nitrogen is, nowadays, a common and relatively cheap coolant, but it remains not the most practical solution ever (liquid methane may also work, but it's not a huge improvement).

I'm not sufficiently expert of the matter to have an informed opinion on whether room temperature superconductivity will be possible, but the fact that many brilliant minds working hard in advanced facilities only managed a 150 K transition temperature does not make me optimistic.

There are also engineering problems: making useful lengths of wires and cables of materials that are ceramics is not so straightforward, as it's the development of appropriate insulation - electrical, but also thermal. However, when it's possible and convenient to install a liquid nitrogen system, I think we'll see more and more superconductors in the future.

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09/01/07

Right-wing Conspiracy Theories

LGF reports a story concerning a suspicious package at Miami port, which after turning positive in field tests for C4 was finally found to be innocuos.

The level of detail of the news story is too low to make an informed judgement, but I have an idea of what may have happened - and of why innocuous items may result positive for explosives.

The sensors used for field tests are simple devices (often, a sort of mass spectrometer called ion mobility spectrometer) compared to laboratory analytical instruments, built to detect one class of compounds - in this case, explosives. What most explosives (TNT, RDX, HMX) have in common is the presence of nitro groups, which I expect to be the main feature of the IMS signature of explosives. However, nitro groups are also contained in other molecules: dyes, certain solvents and drugs. It is also conceivable that compounds like amines, amides and urethanes (that is, common plastics) may give IMS signatures similar to explosives. Also fertilizers contain high amounts of nitrogen, often as nitrates an ureas (which are not nitro groups, but somewhat close). I'm available to conduct an experimental campaign to clarify these issues, if I can find a sponsor...

There is also the selectivity problem: high selectivity is already difficult to achieve with laboratory instuments; field instruments cannot go very far. This means that they aren't very good at discriminating between different chemicals especially within the same class.

As a matter of design bias, I'd prefer my explosive detector to give more false positives than false negatives, because a false positive is a pain in the back, but a false negative can cost many lives.

The story says that the suspect package in fact contained "sprinkler parts", which is another exercise in vagueness. But if these sprinklers became contaminated with some chemical - in the case of agricultural sprinklers, fertilizers - they may result positive for explosives. An investigation should be launched anyway, at least to find who caused that mess by leaving a suspicious package around.

But instead of acting rationally and fact-checking, a lot of LGFers don the tinfoil hat:
Prysorra 1/8/2007 05:46PM PST
*I answer my own question...
Either:
a. False positive for political pressure
b. Security coverup for political reason.
c. They misread their instruments.
C is not likely.

BabbaZee 1/9/2007 05:36AM PST
I seriously doubt they will EVER tell us the truth on these matters until something actually detonates. Everything that is stopped in time will be reported as "false alarms"
And yes, these are only two comments out of 260+, but most of the few on-topic comments have a similar tone. Only a handful of commenters tried to understand what may have actually happened, and apparently none even did a quick search for the principles of explosive detection.

Whenever a false alarm occurs, at LGF it's always like this - many don't even admit the existence of false alarms; there must always be evil, scheming jihadis somewhere and governmental cover-ups to keep the sheeple blissfully unaware. Sounds familiar? It should; it's the same basis of all conspiracy theories. Change a few words, and you'll get Loose Change 911. (Sligthly edited on 10/01)

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Cercasi Musa Ispiratrice

Non ho scritto nulla negli ultimi giorni perchè veramente non sono ispirato. Sì, ho anche avuto le feste di mezzo, ed un paio di cose non proprio divertenti da fare, ma anche se ho qualche articolo quasi pronto nella mia testa, non riesco proprio a sedermi al computer e buttarlo giù.

Spero che si risolva presto, questa situazione. Comunque, posso prendere spunto da un recente post di Robinik (ed i relativi commenti) che narra il suo incontro ravvicinato con Lotta Comunista, per scrivere una mia piccola riflessione.

Chi siano i veri comunisti non si sa, ma certamente non sono mai quelli che stanno commettendo, o hanno commesso, atti stupidi, maleducati od addirittura malvagi ed ingiustificabili. I veri comunisti sono sempre altri, che nessuno riesce mai a definire se non per negazione - esempi: Stalin non era un vero comunista; Mao nemmeno; quelli di Lotta Comunista neppure. E così via.

Seconda piccola riflessione. Quando sono stati gli etiopi (non il famigerato gruppo musicale...) a distribuire un sacco di legnate ai miliziani islamici in Somalia, i nostri media hanno menzionato la quantità di vittime abbastanza di striscio, e non ho sentito nessuno elucubrare sul numero di morti civili. Ora invece gli americani fanno secca una cellula di al-Quaida, e subito spuntano le storie di morti civili e danni collaterali. Ma i media non sono parziali, nono.

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03/01/07

Mugged by Reality (Maghrebis)

That's what happened to my mate on the New Year's Eve night in Parma. To make a long story short, a few of us walked down the stairs to a square below street level, to take a leak in the urinals down there. After a little while, a bunch of youngsters, probably Moroccan or anyway from the Maghreb began insulting us with "Fucking Italians" and the like. I told the screamin one to get lost, then I noticed my mates were orderly retreating up the stairs, so I joined them and from upstairs I even threw a firecracker at the thugs (but it went way off target... alcohol doesn't help with aim).

The the Moroccans or whatever ran away, and I thought they placed a big salute somewhere. But at that point the last of my mates emerged from a archway below - unscathed, but utterly surprised (and drunk) yelled "I think they got my wallet... and cell phone!". He got isolated and was surrounded by four attackers - who did not harm or even threaten him, but with quick hands extracted his goods from his pockets. If we remained grouped, they wouldn't have done anything.

When he calmed down a bit, we called the cops, which arrived a while later, and told us they couldn't do much anyway, especially with the crowd in the streets. One of them also used epithets for the muggers that in London would get him fired from the Police and tried for "racism".

Truth to be told, my mate was very obnoxious that night, and bound to land into trouble. However, his luck ran out not with a citizen understandably pissed off by his antics, but with a gang of thugs out there to cause mayhem. They didn't try to touch me tho. Maybe it's just good luck, but I also am more street-wise than him, and meaner - even in the looks.

The most worrysome part is not the mugging itself, but the close resemblance to what's happening with the Algerians and the like in France. I should get enrolled with the range here as soon as possible...

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