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Index Half-life

Half-life (symbol t1⁄2) is the time required for a quantity to reduce to half its initial value. [1]

35 relations: Atomic nucleus, Biological half-life, Blood plasma, Caesium, Chemical element, Chemical reaction, Computer program, Doubling time, Environmental impact of pesticides, Ernest Rutherford, Expected value, Exponential decay, Half time (physics), Isotope, Isotopes of lead, Law of large numbers, Limit of a function, List of nuclides, List of radioactive isotopes by half-life, Metabolite, Natural logarithm, Nondimensionalization, Nuclear physics, Pesticide, Plant, Probability, Radioactive decay, Radium, Rate equation, RC circuit, Reaction rate constant, Receptor (biochemistry), RL circuit, Sign (mathematics), Tissue (biology).

Atomic nucleus

The atomic nucleus is the small, dense region consisting of protons and neutrons at the center of an atom, discovered in 1911 by Ernest Rutherford based on the 1909 Geiger–Marsden gold foil experiment.

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Biological half-life

The biological half-life of a biological substance is the time it takes for half to be removed by biological processes when the rate of removal is roughly exponential.

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Blood plasma

Blood plasma is a yellowish coloured liquid component of blood that normally holds the blood cells in whole blood in suspension; this makes plasma the extracellular matrix of blood cells.

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Caesium (British spelling and IUPAC spelling) or cesium (American spelling) is a chemical element with symbol Cs and atomic number 55.

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Chemical element

A chemical element is a species of atoms having the same number of protons in their atomic nuclei (that is, the same atomic number, or Z).

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Chemical reaction

A chemical reaction is a process that leads to the transformation of one set of chemical substances to another.

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Computer program

A computer program is a collection of instructions for performing a specific task that is designed to solve a specific class of problems.

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Doubling time

The doubling time is the period of time required for a quantity to double in size or value.

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Environmental impact of pesticides

The impact of pesticides consists of the effects of pesticides on non-target species.

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Ernest Rutherford

Ernest Rutherford, 1st Baron Rutherford of Nelson, HFRSE LLD (30 August 1871 – 19 October 1937) was a New Zealand-born British physicist who came to be known as the father of nuclear physics.

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Expected value

In probability theory, the expected value of a random variable, intuitively, is the long-run average value of repetitions of the experiment it represents.

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Exponential decay

A quantity is subject to exponential decay if it decreases at a rate proportional to its current value.

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Half time (physics)

The 'half time' is the time taken by a quantity to reach one half of its extremal value, where the rate of change is proportional to the difference between the present value and the extremal value (i.e. in exponential decay processes).

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Isotopes are variants of a particular chemical element which differ in neutron number.

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Isotopes of lead

Lead (82Pb) has four stable isotopes: 204Pb, 206Pb, 207Pb, 208Pb.

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Law of large numbers

In probability theory, the law of large numbers (LLN) is a theorem that describes the result of performing the same experiment a large number of times.

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Limit of a function

Although the function (sin x)/x is not defined at zero, as x becomes closer and closer to zero, (sin x)/x becomes arbitrarily close to 1.

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List of nuclides

This list of nuclides shows observed nuclides that either are stable or, if radioactive, have half-lives longer than one hour.

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List of radioactive isotopes by half-life

This is a list of radioactive isotopes ordered by half-life from shortest to longest.

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A metabolite is the intermediate end product of metabolism.

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Natural logarithm

The natural logarithm of a number is its logarithm to the base of the mathematical constant ''e'', where e is an irrational and transcendental number approximately equal to.

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Nondimensionalization is the partial or full removal of units from an equation involving physical quantities by a suitable substitution of variables.

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Nuclear physics

Nuclear physics is the field of physics that studies atomic nuclei and their constituents and interactions.

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Pesticides are substances that are meant to control pests, including weeds.

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Plants are mainly multicellular, predominantly photosynthetic eukaryotes of the kingdom Plantae.

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Probability is the measure of the likelihood that an event will occur.

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Radioactive decay

Radioactive decay (also known as nuclear decay or radioactivity) is the process by which an unstable atomic nucleus loses energy (in terms of mass in its rest frame) by emitting radiation, such as an alpha particle, beta particle with neutrino or only a neutrino in the case of electron capture, gamma ray, or electron in the case of internal conversion.

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Radium is a chemical element with symbol Ra and atomic number 88.

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Rate equation

The rate law or rate equation for a chemical reaction is an equation that links the reaction rate with the concentrations or pressures of the reactants and constant parameters (normally rate coefficients and partial reaction orders).

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RC circuit

A resistor–capacitor circuit (RC circuit), or RC filter or RC network, is an electric circuit composed of resistors and capacitors driven by a voltage or current source.

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Reaction rate constant

In chemical kinetics a reaction rate constant or reaction rate coefficient, k, quantifies the rate of a chemical reaction.

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Receptor (biochemistry)

In biochemistry and pharmacology, a receptor is a protein molecule that receives chemical signals from outside a cell.

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RL circuit

A resistor–inductor circuit (RL circuit), or RL filter or RL network, is an electric circuit composed of resistors and inductors driven by a voltage or current source.

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Sign (mathematics)

In mathematics, the concept of sign originates from the property of every non-zero real number of being positive or negative.

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Tissue (biology)

In biology, tissue is a cellular organizational level between cells and a complete organ.

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Chemical half-life, Half life, Half lives, Half-life period, Half-live, Half-lives, Halflife, Reaction half life, T0.5.


[1] https://en.wikipedia.org/wiki/Half-life

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