An example device includes an isotope portion including a material having at least one isotope, a reaction control portion to cause a chemical reaction including the at least one isotope, and an electrical parameter portion to measure a change in an electrical parameter to determine a change in an amount of the material having the at least one isotope, the electrical parameter to change based on the chemical reaction.

An example device includes an isotope portion including a material having at least one isotope, a reaction control portion to cause a chemical reaction including the at least one isotope, and an electrical parameter portion to measure a change in an electrical parameter to determine a change in an amount of the material having the at least one isotope, the electrical parameter to change based on the chemical reaction.

Systems and methods are presented for a timing device. The timing device includes a first electrode, a second electrode, and an electrolyte. The electrolyte includes a material selected such that an electrodeposit forms on the first electrode when a current is applied between the first electrode and the second electrode. A measurable electrical characteristic of the timing device is indicative of a time-dependent degree of growth of the electrodeposit between the first electrode and the second electrode.

Systems and methods are presented for a timing device. The timing device includes a first electrode, a second electrode, and an electrolyte. The electrolyte includes a material selected such that an electrodeposit forms on the first electrode when a current is applied between the first electrode and the second electrode. A measurable electrical characteristic of the timing device is indicative of a time-dependent degree of growth of the electrodeposit between the first electrode and the second electrode.

This invention relates to thin indicating devices, such as time-temperature indicators and a method of making by applying and UV curing one or more layers of indicating composition are disclosed. For example, an indicator layer is applied on substrate and cured with UV light, immediately followed by an application of an activator layer which is cured by UV light. The device can have other layers, such as a permeable barrier between the activator and indicator layer and a top protective layers which are also UV cured. This fast curing method prevents premature reactions, e.g., diffusion of activator into indicator layer and vice versa during manufacturing.

According to an embodiment, a time reference device is provided. In the embodiment, the time reference device, includes a corrodible element, wherein a corrosion of the corrodible element advances with advancing time, and a sensor configured for providing a sensor signal, the sensor signal depending on a physical property of the corrodible element; wherein the physical property of the corrodible element changes with a corrosion of the corrodible element and the physical property of the corrodible element is at least one of an electrical property, a magnetic property, and an optical property. A barrier may be provided for defining a permeability for a corrosive substance to the corrodible element.

According to an embodiment, a time reference device is provided. In the embodiment, the time reference device, includes a corrodible element, wherein a corrosion of the corrodible element advances with advancing time, and a sensor configured for providing a sensor signal, the sensor signal depending on a physical property of the corrodible element; wherein the physical property of the corrodible element changes with a corrosion of the corrodible element and the physical property of the corrodible element is at least one of an electrical property, a magnetic property, and an optical property. A barrier may be provided for defining a permeability for a corrosive substance to the corrodible element.

A time validation indicator is disclosed comprising at least a receiving layer and an activating layer. The receiving layer comprises at least one or more masking colorants and one or more deactivators that cause and maintain the one or more masking colorants in an initial colored state. The activating layer comprises at least one or more migratory activators that migrate into the receiving layer upon at least a portion of the receiving layer being placed in contact with at least a portion of the activating layer to initiate a predetermined time period. The migration of the one or more migratory activators into the receiving layer causes at least a portion of the one or more masking colorants to advance to a final colorless state resulting in a visual color change of the receiving layer that indicates the predetermined time period has elapsed. Also disclosed are methods for creating and using the inventive time validation indicator.

A time validation indicator is disclosed comprising at least a receiving layer and an activating layer. The receiving layer comprises at least one or more masking colorants and one or more deactivators that cause and maintain the one or more masking colorants in an initial colored state. The activating layer comprises at least one or more migratory activators that migrate into the receiving layer upon at least a portion of the receiving layer being placed in contact with at least a portion of the activating layer to initiate a predetermined time period. The migration of the one or more migratory activators into the receiving layer causes at least a portion of the one or more masking colorants to advance to a final colorless state resulting in a visual color change of the receiving layer that indicates the predetermined time period has elapsed. Also disclosed are methods for creating and using the inventive time validation indicator.

The timing device is a lifetime monitor for indicating when the usable lifetime of a product has ended or for indicating the timing for regular usage of a product. The timing device has a timing initiator, a power supply in the form of a membrane zinc air battery and a visual or audible indicator. The timing initiator is a tear-off air blocking membrane which lets in air when the tear off film is removed. The timing device is capable of indicating a predetermined passage of time which is substantially independent of ambient temperature.