Back to results
US 7,246,939 B1Granted
Measurement of thermal diffusivity, thermal conductivity, specific heat, specific absorption rate, thermal power, heat transfer coefficient, heat of reaction and membrane permeability by nuclear magnetic resonance
OwnerDavid H. Gultekininventor
Life of this patent
Estimating the term…
Abstract
This invention utilizes the nuclear magnetic resonance imaging and spectroscopy to experimentally measure thermal diffusivity, thermal conductivity, specific heat, specific absorption rate, thermal power, heat transfer coefficient, heat of reaction and the membrane permeability in substances and systems.
Claims22
A method of measuring the thermal diffusivity in a substance by nuclear magnetic resonance, said method comprising:
- a. providing a nuclear magnetic resonance imaging and spectroscopy apparatus,
- b. placing said substance in said nuclear magnetic resonance imaging and spectroscopy apparatus,
- c. measuring one or more nuclear magnetic resonance properties comprising nuclear magnetic resonance frequency ω or nuclear spin phase shift φ or nuclear magnetization M(te,T) or equilibrium nuclear magnetization M(0,T) or spin-lattice relaxation time T1(T) or spin-lattice relaxation rate R1(T) or spin—spin relaxation time T2(T) or spin—spin relaxation rate R2(T) or effective spin—spin relaxation time T2*(T) or effective spin—spin relaxation rate R2*(T) or spin diffusion coefficient D(T) in said substance,
- d. providing a thermal energy to heat a volume in said substance or to heat an absorber placed in close contact with said substance or within said substance,
- e. measuring and normalizing the temporal variation of one or more said nuclear magnetic resonance properties in step (c) in said substance in imaging voxels perpendicular to the direction of the heat propagation at multiple distances from the heated volume or absorber by acquiring multiple nuclear magnetic resonance images,
- f. determining the time for the maximal change in said temporal variation of one or more said nuclear magnetic resonance properties in step (e) at multiple distances,
- g. determining said thermal diffusivity in said substance using the relation between said square of the distance and said time for the maximal change in said temporal variation of one or more said nuclear magnetic resonance properties in step (f).
4 more elements
A method of measuring the thermal conductivity in a substance by nuclear magnetic resonance, said method comprising:
- a. placing said substance in a nuclear magnetic resonance imaging and spectroscopy apparatus,
- b. providing a known quantity of a thermal flux to heat a volume in said substance or to heat an absorber placed in close contact with said substance or within said substance,
- c. measuring the temperature dependence of one or more nuclear magnetic resonance properties comprising nuclear magnetic resonance frequency ω or nuclear spin phase shift φ or nuclear magnetization M(te,T) or equilibrium nuclear magnetization M(0,T) or spin-lattice relaxation time T1(T) or spin-lattice relaxation rate R1(T) or spin—spin relaxation time T2(T) or spin—spin relaxation rate R2(T) or effective spin—spin relaxation time T2*(T) or effective spin—spin relaxation rate R2*(T) or spin diffusion coefficient D(T) in said substance,
- d. determining the gradient of one or more said nuclear magnetic resonance properties in step (c) in the direction of the thermal conduction in said substance,
- e. determining said thermal conductivity in said substance using the thermal conduction relation, said thermal flux in step (b), said temperature dependence of one or more said nuclear magnetic resonance properties in step (c), said gradient of one or more said nuclear magnetic resonance properties in step (d).
2 more elements
A method of measuring the specific heat and the specific absorption rate in a substance by nuclear magnetic resonance, said method comprising:
- a. placing said substance in a nuclear magnetic resonance imaging and spectroscopy apparatus,
- b. providing a known thermal power to heat said substance or to heat an absorber placed in close contact with said substance or within said substance,
- c. measuring the temperature dependence of one or more nuclear magnetic resonance properties comprising nuclear magnetic resonance frequency ω or nuclear spin phase shift φ or nuclear magnetization M(te,T) or equilibrium nuclear magnetization M(0,T) or spin-lattice relaxation time T1(T) or spin-lattice relaxation rate R1(T) or spin—spin relaxation time T2(T) or spin—spin relaxation rate R2(T) or effective spin—spin relaxation time T2*(T) or effective spin—spin relaxation rate R2*(T) or spin diffusion coefficient D(T) in said substance,
- d. measuring the temporal variation of one or more said nuclear magnetic resonance properties in step (c) in the heated volume in said substance by acquiring a series of nuclear magnetic resonance images of the heated volume in time,
- e. determining said specific heat in said substance using the thermal power and temperature rise relation, said thermal power, said temperature dependence of one or more nuclear magnetic resonance properties in step (c), said temporal variation of one or more said nuclear magnetic resonance properties in step (d) and the mass of said substance,
- f. subjecting said substance to the electromagnetic radiation and measuring the rate of one or more said nuclear magnetic resonance properties in step (c) in said substance by acquiring a series of nuclear magnetic resonance images of the heated volume in time,
- g. determining said specific absorption rate in said substance using the specific heat and temperature rise relation, said temperature dependence of one or more said nuclear magnetic resonance properties in step (c), said specific heat measured in step (e), said rate of one or more said nuclear magnetic resonance properties measured in step (f).
4 more elements
A method of measuring the thermal power and the thermal energy by nuclear magnetic resonance, said method comprising:
- a. placing the substance in a nuclear magnetic resonance imaging and spectroscopy apparatus,
- b. measuring the temperature dependence of one or more nuclear magnetic resonance properties comprising nuclear magnetic resonance frequency ω or nuclear spin phase shift φ or nuclear magnetization M(te,T) or equilibrium nuclear magnetization M(0,T) or spin-lattice relaxation time T1(T) or spin-lattice relaxation rate R1(T) or spin—spin relaxation time T2(T) or spin—spin relaxation rate R2(T) or effective spin—spin relaxation time T2*(T) or effective spin—spin relaxation rate R2*(T) or spin diffusion coefficient D(T) in said substance,
- c. providing a known thermal power to heat said substance or to heat an absorber placed in close contact with said substance or within said substance, measuring the temporal variation of one or more said nuclear magnetic resonance properties in step (b) in the heated volume in said substance by acquiring a series of nuclear magnetic resonance images of the heated volume in time, determining said specific heat in said substance using the thermal power and temperature rise relation, said thermal power, said temporal variation of one or more said nuclear magnetic resonance properties in step (b), said temperature dependence of one or more nuclear magnetic resonance properties in step (b), and the mass of said substance,
- d. providing a thermal source to heat said substance and measuring the temporal variation of one or more said nuclear magnetic resonance properties in step (b) in the heated volume in said substance by acquiring a series of nuclear magnetic resonance images of the heated volume in time,
- e. determining said thermal power of said thermal source using the thermal power and temperature rise relation, said temperature dependence of one or more said nuclear magnetic resonance properties in step (b), said specific heat of said substance measured in step (c), said temporal variation of one or more said nuclear magnetic resonance properties in step (d) and the mass of said substance,
- f. determining said thermal energy change using said temperature dependence of one or more said nuclear magnetic resonance properties in step (b), said specific heat of said substance measured in step (c), the change in one or more said nuclear magnetic resonance properties in step (d) and the mass of said substance.
3 more elements
A method of measuring the heat transfer coefficient by nuclear magnetic resonance, said method comprising:
- a. placing the substance in a nuclear magnetic resonance imaging and spectroscopy apparatus,
- b. providing a fluid surrounding said substance and measuring the temporal variation of one or more nuclear magnetic resonance properties comprising nuclear magnetic resonance frequency ω or nuclear spin phase shift φ or nuclear magnetization M(te,T) or equilibrium nuclear magnetization M(0,T) or spin-lattice relaxation time T1(T) or spin-lattice relaxation rate R1(T) or spin—spin relaxation time T2(T) Or spin—spin relaxation rate R2(T) or effective spin—spin relaxation time T2*(T) or effective spin—spin relaxation rate R2*(T) or spin diffusion coefficient D(T) in said substance,
- c. providing a known thermal power to heat said substance or to heat an absorber placed in close contact with said substance or within said substance, measuring the temporal variation of one or more said nuclear magnetic resonance properties in step (b) in the heated volume in said substance by acquiring a series of nuclear magnetic resonance images of the heated volume in time, determining said specific heat in said substance using the thermal power and temperature rise relation, said thermal power, said temporal variation of one or more said nuclear magnetic resonance properties in step (b), said temperature dependence of one or more nuclear magnetic resonance properties in step (b), and the mass of said substance,
- d. determining the thermal relaxation rate by measuring the slope of the logarithm of dimensionless form of one or more said nuclear magnetic resonance properties in step (b) versus time,
- e. determining said heat transfer coefficient using the specific heat and thermal relaxation rate relation, said specific heat measured in step (c), said thermal relaxation rate in step (d), the mass and the surface area of said substance.
2 more elements
A method of measuring the heat of reaction by nuclear magnetic resonance, said method comprising:
- a. placing at least one substance by itself or imbedded in a surrounding substance in a nuclear magnetic resonance imaging and spectroscopy apparatus,
- b. measuring the temperature dependence of one or more nuclear magnetic resonance properties comprising nuclear magnetic resonance frequency ω or nuclear spin phase shift φ or nuclear magnetization M(te,T) or equilibrium nuclear magnetization M(0,T) or spin-lattice relaxation time T1(T) or spin-lattice relaxation rate R1(T) or spin—spin relaxation time T2(T) or spin—spin relaxation rate R2(T) or effective spin—spin relaxation time T2*(T) or effective spin—spin relaxation rate R2*(T) or spin diffusion coefficient D(T) in said substance or in said surrounding substance,
- c. providing a known thermal power to heat said substance or said surrounding substance or to heat an absorber placed in close contact with said substance or within said substance or with said surrounding substance or within said surrounding substance, measuring the temporal variation of one or more said nuclear magnetic resonance properties in step (b) in the heated volume in said substance or in said surrounding substance by acquiring a series of nuclear magnetic resonance images of the heated volume in time, determining said specific heat in said substance or said surrounding substance using the thermal power and temperature rise relation, said thermal power, said temporal variation of one or more said nuclear magnetic resonance properties in step (b), said temperature dependence of one or more nuclear magnetic resonance properties in step (b), and the mass of said substance or said surrounding substance,
- d. reacting one or more additional substances in said substance and determining the change in one or more said nuclear magnetic resonance properties in step (b) in said substance or in said surrounding substance,
- e. determining the thermal energy change as a result of said reaction using said temperature dependence of one or more said nuclear magnetic resonance properties in step (b) in said substance or in said surrounding substance, said specific heat of said substance or said surrounding substance measured in step (c), said change in one or more said nuclear magnetic resonance properties in step (d) in said substance or in said surrounding substance and the mass of said substance or said surrounding substance,
- f. determining said heat of reaction using the amount of said thermal energy change in said substance or said surrounding substance and the moles of reacting substances,
- g. determining the reaction to be exothermic on the basis of increase or endothermic on the basis of decrease in said thermal energy change in step (e).
4 more elements
A method of measuring the membrane permeability by nuclear magnetic resonance, said method comprising:
- a. placing one or more substances separated by at least one membrane in a nuclear magnetic resonance imaging and spectroscopy apparatus,
- b. measuring one or more nuclear magnetic resonance properties comprising nuclear magnetic resonance frequency ω or nuclear spin phase shift φ or nuclear magnetization M(te,T) or equilibrium nuclear magnetization M(0,T) or spin-lattice relaxation time T1(T) or spin-lattice relaxation rate R1(T) or spin—spin relaxation time T2(T) or spin—spin relaxation rate R2(T) or effective spin—spin relaxation time T2*(T) or effective spin—spin relaxation rate R2*(T) or spin diffusion coefficient D(T) in at least one substance on at least one side of at least one membrane,
- c. measuring the compositional or volume fraction dependence of one or more said nuclear magnetic resonance properties in step (b) in one or more substances on at least one side of at least one said membrane,
- d. measuring the transport of at least one substance through at least one membrane in time by measuring the temporal variation of one or more said nuclear magnetic resonance properties in step (b) in at least one substance on at least one side of at least one said membrane,
- e. determining said membrane permeability using the flux relation, said compositional or volume fraction dependence of one or more said nuclear magnetic resonance properties in one or more substances in step (c), said temporal variation of one or more said nuclear magnetic resonance properties in step (d), the initial volume of one or more said substances and the surface area of at least one said membrane.
2 more elements
Dependencies are inferred from the claim text.