There are two methods for determining the absolute age of a rock, so-called radiochronology:
- The isochronous method
- The cosmogenic nuclide method
These two methods are based on natural nuclear disintegration of unstable nuclei present in the rock whose proportion of father nuclei (radioactive nuclei) and wire nuclei (the resulting cores more stable) is measured. The measurements are made by mass spectrometry (and more rarely by thermoluminescence or luminescence stipulated optically or by infrared).
As a reminder, the radioactivity of radionuclides is manifested in different ways:
- The alpha decay with a helion emission: for example 226Ra → 222Rn + 4He
- Beta decay (positive or negative): for example the decay β- of rubidium-87: 87RB → 87Rb → 87Sr + e– + anti ν
- Spontaneous fission (and induced fission) whose nuclear fragments may or can not be radioactive: for example 244Pu → 240U by alpha disintegration.
Nuclear disintegration obeys some natural rules such as the Radioactive Decay Act. This law stipulates that for a given father-son nuclear couple, the probability of disintegrating the core father per unit of time is a constant: it is the decay constant, symbolized by λ.
The disintegration of unstable nuclei and particle detectors obeying the quantum phenomena laws, we can not say with precision alien of nuclei will disintegrate at a given moment or will be measured by an instrument (eg a particle detector) . On the other hand, statistically one can accurately assess this proportion called the period (t) or half-life of an element. This is the necessary interval for 50% of the father radionuclides naturally disintegrate into wire elements. This period varies according to the elements between a few milliseconds and several tens of billions of years.
In the case of well-known carbon-14, the unstable father core is the 14C whose half-life is 5730 ± 40 years and the wire core is 12C stable. In other words, after approximately 5730 years, 50% of 14C isotopes will be transformed into 12C. 5730 years later, 50% of the remaining 14C isotopes will be transformed into 12c and so on.
We are talking about long-term or long life element when its half-life is similar or longer than the age of the solar system. In other cases, it is a short period of time or short life (even if it varies between a fraction of nanosecond and a few billion years).
In almost all minerals, father, son and other isotopes are present in variable proportions that depend on the composition of the original magma and the time it took to cool or crystallize (case of Quartz, feldspar, micas, etc.).
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Right — have been messing about with this thing for maybe five months now and it’s basically bookmarked at this point, so figured I’d say something since someone asked me the other day. I’m based in the UK, generally do football and horses, nothing mad, so take it how you like.
The reason I started using it was genuinely embarrassing — I couldn’t ever figure out what an e/w return actually came to once you get five places instead of three. I’d just eyeball it and get a shock. Now stick my stake in first, every time, even a simple single bet.
The single bet calculator tool is the part I’m on daily — you put in stake and odds and it shows the return with no faffing, either odds format. Same tool covers the multiples — trebles maths, lucky 15s, a yankee, honestly that’s where most people I know lose track. If you fancy a poke about, it’s over at exchange bet calculator — free, no signup.
The thing that genuinely shifted things for me is the nerdier bits. There’s an implied probability converter and it makes obvious how much the bookie’s taking, plus a kelly calculator — I run quarter kelly as the full version is a quick route to a dead bankroll. The dutch tool gets used a fair bit if I’m covering two or three runners.
Not all sunshine though. Its interface feels very functional, let’s say — zero frills, looks like it was built by someone who cares more about maths than colours. Phone-wise it’s usable though the acca grid are a squeeze. There’s nothing on the app store, it’s browser only — fine by me just flagging it.
Anyway. Doesn’t cost anything, no ads shoved in your face, does what it says. Anyone who still adds it up in their head, try it — it’s saved me a load of “wait, that’s it?” moments.
Ya llevo unos cuantos meses en 888starz y para que mentir no esperaba gran cosa, porque aqui en Espana uno se cansa de paginas que venden humo. El registro no me llevo ni dos minutos, correo, contrasena y listo, y el minimo para depositar es de 1 euro, cosa que agradezco para tantear.
En cuanto a maquinas tienen un catalogo enorme — creo que pasan de 8.000 slots de proveedores como Pragmatic Play, NetEnt, Play’n GO, Betsoft y Yggdrasil. Mis habituales son Book of Dead y Gates of Olympus, aunque he tocado tambien alguna de Microgaming. Lo que me raya es que el buscador va un poco lento cuando tienes 8.000 cosas delante.
La zona en vivo es de Evolution, basicamente y eso se nota: ruletas con crupieres de verdad, los game shows tipo Crazy Time si te va el rollo espectaculo. El paquete de bienvenida es de un 100% hasta 300€ y unas 150 tiradas, hay que apostarlo x40, que no es regalado pero tampoco un robo. Va rotando algun free spin sin deposito, puedes mirar lo que hay vigente directamente en 888starz application porque cambian cada mes.
El tema de sacar pasta me ha ido mejor de lo que pensaba. Saque hace poco por Skrill y entro casi al momento. Con tarjeta tarda mas, nada nuevo. Tienen Neteller, Bitcoin y USDT si no te asusta el tema.
El movil va suave, la app de Android existe si bien la version web hace el mismo apano. El soporte esta en espanol, me atendieron rapido con una duda de documentacion. La licencia es de Curazao, asi que no es un.es regulado y conviene tenerlo claro. A mi de momento me ha respondido, y sin volverse loco con los bonos.
Ya llevo como cinco meses con 888starz y la verdad entre con la mosca detras de la oreja, porque aqui en Espana acabas quemado de sitios que se caen cada dos por tres. Abrir la cuenta me llevo un rato minimo, correo, contrasena y listo, y el minimo para depositar esta en 1 euro, cosa que agradezco para tantear.
De tragaperras tienen un catalogo enorme — creo que pasan de 8.000 titulos repartidos entre Pragmatic Play, NetEnt, Play’n GO, Betsoft y Yggdrasil. Mis habituales son Sweet Bonanza y Book of Dead, eso si de vez en cuando pruebo cosas de Big Time Gaming. Lo que si el buscador va un poco lento cuando hay tantisimo.
La parte de crupier real es de Evolution, basicamente y se nota la diferencia: blackjack con gente real, Crazy Time si te va el rollo espectaculo. El bono de bienvenida es de un 100% con 100 tiradas gratis, hay que apostarlo unas 35 veces, nada raro comparado con otros. Va rotando algun free spin sin deposito, conviene revisar los terminos actualizados directamente en 888starz aviator app porque cambian cada mes.
El tema de sacar pasta va bastante fino. Saque la semana pasada via e-wallet y entro casi al momento. Con Visa se va a dos o tres dias, nada nuevo. Van con Neteller, Bitcoin y USDT que es lo mas rapido con diferencia.
En el telefono va suave, hay APK para Android aunque la web movil me va igual de bien. El soporte responde en espanol, no fue instantaneo pero tampoco eterno cuando pregunte por el KYC. Licencia de Curazao, asi que no es un.es regulado y hay que saberlo antes de entrar. Yo sigo ahi, con sus cosas, pero ojo con el rollover de las promos.