An apparatus includes an absorbing material configured to absorb electromagnetic energy. The apparatus also includes a thermochromic material in or on the absorbing material, where the thermochromic material is configured to change one or more visible characteristics based on the absorbing material being heated above a specified temperature threshold. The absorbing material may be configured to absorb radio frequency signals or microwave signals. The one or more visible characteristics may include at least one of: color and opacity.

An apparatus includes an absorbing material configured to absorb electromagnetic energy. The apparatus also includes a thermochromic material in or on the absorbing material, where the thermochromic material is configured to change one or more visible characteristics based on the absorbing material being heated above a specified temperature threshold. The absorbing material may be configured to absorb radio frequency signals or microwave signals. The one or more visible characteristics may include at least one of: color and opacity.

To address the problem of providing a temperature history indicator capable of specifying a time when a temperature deviated from a set temperature range, a temperature history indicator according to the present invention is characterized in being provided with a substrate and temperature indicators that irreversibly change color upon deviation from a set temperature range, and in that a plurality of the temperature indicators are provided on the substrate, the temperatures at which the temperature indicators change color a within ±2° C. of each other, and the temperature indicators change color after different amounts of time from deviation from the set temperature range.

To address the problem of providing a temperature history indicator capable of specifying a time when a temperature deviated from a set temperature range, a temperature history indicator according to the present invention is characterized in being provided with a substrate and temperature indicators that irreversibly change color upon deviation from a set temperature range, and in that a plurality of the temperature indicators are provided on the substrate, the temperatures at which the temperature indicators change color a within ±2° C. of each other, and the temperature indicators change color after different amounts of time from deviation from the set temperature range.

A temperature sensor includes a solar cell, and a thermochromic resin covering the solar cell and having a light transmittance changeable according to a temperature change.

The invention provides an acoustic material structure and an assembly method of the acoustic radiation structure. The acoustic material structure comprises acoustic units which can be attached onto surfaces of acoustic radiation structures. Each acoustic unit comprises a thin sheet, an air cavity between the thin sheet and the surface of the sound radiation structure, and openings penetrating through the acoustic unit with one end connected to the cavity. The openings can reduce the spring effect of the fluid medium in the cavity, so that the acoustic units attached onto the surface of the sound radiation structure can provide low-frequency sound insulation effects. The acoustic unit may also include support bodies, mass blocks, and constraint bodies. The working frequencies of the acoustic unit can be regulated by the support bodies, mass blocks and constraint bodies. The acoustic material structure can effectively suppress sound radiation from low- and middle-frequency sound waves which have relatively larger wavelength under costs of small weight and space. Moreover, the acoustic material structure can enhance the exchange rate of the heat from the attached structure surfaces by the vibration of the thin sheet.

A temperature sensor, a temperature monitoring method, and a temperature monitoring device are provided. The temperature sensor includes: at least one electroluminescent device, and a power supply device electrically coupled to the electroluminescent device. The power supply device is configured to provide a turn-on voltage of the electroluminescent device at a predetermined temperature to the electroluminescent device.

A temperature sensor, a temperature monitoring method, and a temperature monitoring device are provided. The temperature sensor includes: at least one electroluminescent device, and a power supply device electrically coupled to the electroluminescent device. The power supply device is configured to provide a turn-on voltage of the electroluminescent device at a predetermined temperature to the electroluminescent device.

A method for providing a temperature sensitive element surrounding a surgical instrument to provide a visual indication of tip temperature to an operator of the instrument. Change in color of the element is an indication to the operator to be aware of the generated heat and reduce power to the instrument accordingly. When the tip of a surgical instrument heats up to a certain threshold that would cause harm, a reversible thermochromic property of the element may change colors in direct relation to the rise and fall of temperature.

A method for providing a temperature sensitive element surrounding a surgical instrument to provide a visual indication of tip temperature to an operator of the instrument. Change in color of the element is an indication to the operator to be aware of the generated heat and reduce power to the instrument accordingly. When the tip of a surgical instrument heats up to a certain threshold that would cause harm, a reversible thermochromic property of the element may change colors in direct relation to the rise and fall of temperature.