A method for performing distributed pressure sensing including the steps of, forming a grating in a birefringent fiber, measuring the birefringence distribution along the length of the birefringent fiber, and determining pressure present along the length of the fiber using the measured the birefringence distribution. The invention also relates to a corresponding sensing device.

A nanoparticle sensor apparatus includes a silicon-based nanoparticle having a centrosymmetric crystalline structure. A lanthanide atom embedded within the silicon-based nanoparticle provides light emission when the sensor apparatus undergoes pressure loading. This sensor apparatus may be encapsulated in a polymer matrix to form a nanoparticle sensor matrix apparatus which may be located on or in a structure. To measure the pressure on such a structure, a UV light source illuminates the sensor apparatus. An optical emission detector detects the intensity of light emitted from the sensor in response, while a processor correlates that intensity to the pressure loading.

The present disclosure relates to the display technical field, more particularly, to a pressure sensitive film and a manufacturing method thereof. The pressure sensitive film comprises a substrate, a color displaying layer and a color forming layer laminated sequentially; the other surface of the substrate opposite to the surface adjoining the color displaying layer is for bearing pressure; the color forming layer comprises at least one color forming unit, each of which comprises at least two color sacs, and the at least two color sacs have pressure-bearing thresholds different from each other, and operate when the pressure borne reaches their pressure-bearing thresholds; the color displaying layer displays corresponding colors according to the operation conditions of the color sacs, and each color corresponds to a set pressure value. The pressure sensitive film provided by the present disclosure determines a pressure range of the device according to the different colors, realizing effective monitoring of the device pressure; and determining the flatness of the device according to the evenness of the colors of tested regions, thus combining the pressure test and flatness test, so as to make the routine device pressure monitoring more convenient.

There are provided a paste-like composition for pressure measurement, including a microcapsule that encompasses an electron-donating dye precursor and an electron-accepting compound that causes the electron-donating dye precursor to develop a color, and a pressure measurement method using the paste-like composition for pressure measurement.

The present disclosure relates to a packaging box, a device and method for detecting damage, a detection apparatus, and a storage medium, and belongs to the field of packaging technologies. The packaging box includes a plurality of packaging cardboards that are combined into the packaging box, wherein at least one packaging cardboard of the plurality of packaging cardboards includes: a surface paper; a backing paper; at least one layer of a core paper; and at least one external force detecting member, wherein the at least one layer of the core paper is disposed between the surface paper and the backing paper, and wherein the at least one external force detecting member is configured to measure a strength value of an external force when the packaging cardboard is subjected to the external force.

A pressure sensor and a pressure detecting method are provided, the pressure sensor includes a liquid crystal cell including a cholesteric liquid crystal layer, a liquid crystal state detector module and a pressure finder module, and the liquid crystal cell includes a pressure receiving surface. The liquid crystal state detector module is configured to detect a liquid crystal arrangement state in the cholesteric liquid crystal layer in a situation where a pressure is applied on the pressure receiving surface of the liquid crystal cell; the pressure finder module is configured to find a value of the pressure corresponding to the liquid crystal arrangement state from a pre-stored correspondence table.

Disclosed is a tamper evident backing system, comprising an adhesive backing, the adhesive backing having a main body and sectioned portions, wherein the adhesive backing includes an outer surface is configured to adhere to a second surface, and wherein upon removal of an attached adhesive backing, said sectioned portions are configured to detach from main body and remain on said second surface.

Provided are a material for pressure measurement, including a color forming layer that contains microcapsules A encapsulating an electron-donating colorless dye precursor and microcapsules B not encapsulating an electron-donating colorless dye precursor, in which a volume standard median diameter D50A of the microcapsules A and a volume standard median diameter D50B of the microcapsules B satisfy Equation 1; a material composition for pressure measurement; and a material set for pressure measurement:
D50A<D50B  Equation 1.

A system for monitoring downhole cement quality in a cased well includes an active acoustic source that generates acoustic waves, a distributed acoustic sensor, and a controller. The distributed acoustic sensor includes an optical fiber disposed on an outer surface of a casing of the cased well; a pulsed laser coupled to the optical fiber and that transmits pulses of laser light along the optical fiber; a sensor that detects light that is backscattered and reflected by the optical fiber; and a processor that controls the pulsed laser, receives signals from the sensor, and converts the signals into acoustic information. The controller receives the acoustic information from the processor and identifies well integrity loss.

A system for assaying forces applied by cells includes an optically transparent substrate comprising a soft material having a Young's modulus within the range of about 3 kPa to about 100 kPa. An array of molecular patterns is disposed on a surface of the optically transparent substrate, the molecular patterns include fluorophore-conjugated patterns adherent to cells. The system includes at least one light source configured to excite the fluorophore-conjugated patterns and an imaging device configured to capture fluorescent light emitted from the fluorophore-conjugated patterns. Dimensional changes in the size of the patterns are used to determine contractile forces imparted by cells located on the patterns.