초록 ▼

A bag having a built-in closure tab is defined. The closure tab is formed from the outer layer of the laminate which makes up the bag. When a user of the bag wishes to close the bag, the user folds or rolls the sides of the bag together down the side of the bag having the tab. The tab is partially s

A bag having a built-in closure tab is defined. The closure tab is formed from the outer layer of the laminate which makes up the bag. When a user of the bag wishes to close the bag, the user folds or rolls the sides of the bag together down the side of the bag having the tab. The tab is partially separated from the rest of the outer layer of the laminate. A pressure sensitive adhesive disposed on the interior surface of the tab is used to affix the tab to the rolled down portion of the bag, preventing unwanted opening of the bag. The tab may be affixed and removed from the rolled down portion a number of times, thereby allowing the user to open and reseal the bag as many times as desired.

대표청구항 ▼

A bag having a built-in closure tab is defined. The closure tab is formed from the outer layer of the laminate which makes up the bag. When a user of the bag wishes to close the bag, the user folds or rolls the sides of the bag together down the side of the bag having the tab. The tab is partially s

A bag having a built-in closure tab is defined. The closure tab is formed from the outer layer of the laminate which makes up the bag. When a user of the bag wishes to close the bag, the user folds or rolls the sides of the bag together down the side of the bag having the tab. The tab is partially separated from the rest of the outer layer of the laminate. A pressure sensitive adhesive disposed on the interior surface of the tab is used to affix the tab to the rolled down portion of the bag, preventing unwanted opening of the bag. The tab may be affixed and removed from the rolled down portion a number of times, thereby allowing the user to open and reseal the bag as many times as desired. ture is substantially 70° C. above ambient temperature. 3. An energy meter according to claim 1, in which the second temperature is substantially 50° C. above the ambient temperature. 4. An energy meter according to claim 1, wherein the means to measure the speed of sound in the gas is a resonator arranged to contain samples of the gas supplied, the resonator being arranged to have an acoustic signal over a range of frequencies applied to its interior when it contains samples of the gas supplied and having means to detect the magnitude of the acoustic signal within the resonator at each applied frequency and from the resonant frequency determine the speed of sound of the gas. 5. An energy meter according to claim 1, wherein the means to measure a volume of gas supplied is a gas flow meter. 6. An energy meter according to claim 5, wherein the gas flow meter is a diaphragm meter. 7. An energy meter according to claim 5, wherein the gas flow meter is an ultrasonic meter. 8. An energy meter according to claim 1, including means to measure the ambient temperature of the gas and wherein the means producing the calorific value of the gas is arranged to use the formula: CV=a·ThCH+b·ThCL+c·SoS+d·Ta+e·Ta2+f, where CV is the calorific value of the gas, where ThCHis the first thermal conductivity of the gas at said first temperature, where THCLis the second thermal conductivity of the gas at said second temperature which is lower than said first temperature, where SoS is the speed of sound in gas at ambient temperature, and where Tais the ambient temperature of said gas whereof said thermal conductivities are measured, the first and second temperatures being greater than said ambient temperature, and a, b, c, d, e, and f are constants. 9. An energy meter according to claim 8, in which SoS is the speed of sound in m/s, the thermal conductivities are in units of Watts/meter×degrees Kelvin (W/m·k), the temperature Taand the first and second temperatures are in degrees Celsius, and the calorific value is in megajoules/standard cubic metre (MJ/m3st). 10. An energy meter according to claim 8, in which the meter is arranged to measure the energy value of fuel gas. 11. An energy meter according to claim 10, in which the fuel gas is natural gas. 12. An energy meter according to claim 11, in which the gas comprises at least one hydrocarbon gas which is methane, and at least one of nitrogen and carbon dioxide. 13. An energy meter according to claim 11, in which: a is substantially 36.25649, b is substantially -45.5768, c is substantially 0.047029, d is substantially 0.091067, e is substantially 0.00074, and f is substantially 24.18731. 14. A method of measuring a quantity of energy comprising: measuring a volume of gas supplied; measuring a calorific value of the supplied gas including measuring the speed of sound in the gas and using the speed of sound in an operation producing the calorific value of the gas corresponding to said speed of sound; and calculating an energy value corresponding to the measured volume of gas supplied and the measured calorific value; wherein the measurement of the calorific value of the gas further includes measuring a first thermal conductivity of the gas at a first temperature, measuring a second thermal conductivity of the gas at a second temperature which differs from the first temperature, and producing the calorific value of the gas using the first and second thermal conductivities in addition to the speed of sound in the operation producing calorific value of the gas corresponding to the speed of sound, and the first and second thermal conductivities. 15. A method according to claim 14, in which the first temperature is substantially 70° C. above ambient temperatures. 16. A method according to claim 14, in which the second temperature is substantially 50° C