In recent years, strain sensors have penetrated various fields. The capability of sensors to convert physical signals into electrical signals is of great importance in healthcare. However, it is ...still challenging to obtain sensors with high sensitivity, large operating range and low cost. In this paper, a stretchable strain sensor made of a double-layer conductive network, including a biomimetic multilayer graphene-Ecoflex (MLG-Ecoflex) substrate and a multilayer graphene-carbon nanotube (MLG-CNT) composite up-layer was developed. The combined action of the two layers led to an excellent performance with an operating range of up to 580% as well as a high sensitivity (gauge factor (GF
) of 1517.94). In addition, a pressure sensor was further designed using the bionic vein-like structure with a multi-layer stacking of MLG-Ecoflex/MLG-CNT/MLG-Ecoflex to obtain a relatively high deformation along the direction of thickness. The device presented a high sensing performance (up to a sensitivity of 0.344 kPa
) capable of monitoring small movements of the human body such as vocalizations and gestures. The good performance of the sensors together with a simple fabrication procedure (flip-molding) make it of potential use for some applications, for example human health monitoring and other areas of human interaction.
Strain sensors that can rapidly and efficiently detect strain distribution and magnitude are crucial for structural health monitoring and human–computer interactions. However, traditional electrical ...and optical strain sensors make access to structural health information challenging because data conversion is required, and they have intricate, delicate designs. Drawing inspiration from the moisture-responsive coloration of beetle wing sheaths, we propose using Ecoflex as a flexible substrate. This substrate is coated with a Fabry–Perot (F–P) optical structure, comprising a “reflective layer/stretchable interference cavity/reflective layer”, creating a dynamic color-changing visual strain sensor. Upon the application of external stress, the flexible interference chamber of the sensor stretches and contracts, prompting a blue-shift in the structural reflection curve and displaying varying colors that correlate with the applied strain. The innovative flexible sensor can be attached to complex-shaped components, enabling the visual detection of structural integrity. This biomimetic visual strain sensor holds significant promise for real-time structural health monitoring applications.
The structural color based on the Fabry–Perot (F–P) resonator has been extensively applied lithography-free and tunable color displays. Conventional F–P cavity-based structural color technology ...exhibits a wide half maximum full width (fwhm), thus causing low color saturation. In this study, a Sc0.2Sb2Te3(SST) based structure of multi-order F–P cavity resonance was proposed to obtain high-saturation colors. The surface absorber of the multi-order F–P resonator structure was coated with an SST film, such that the reflection effect at nonresonant wavelengths was reduced. Moreover, ITO layer stacking served as F–P cavity resonance for multi-level modulation, and only a resonant wavelength was allowed to reflect. On that basis, the fwhm of nearly 25 nm and a peak reflectance of 90 was achieved. With the above structure, the color saturation can be dynamically regulated by the phase state of the SST. It is noteworthy that 60% sRGB color gamut space and 50% aRGB color gamut space can be currently achieved. The proposed modulation subsurface is expected to expand the color range of high-level and micro-nano display technology.
Natural gas is a clean and efficient energy source. Shale gas, one of the unconventional natural gases, is becoming an indispensable part of natural gas. Compared with marine facies shale gas, which ...has large-scale exploitation, marine and continental transitional facies shale gas have greater development potential. It could be the new direction of development in the future. In this article, the basic geological characteristics, sedimentary environment, and reservoir characteristics of organic-rich transitional facies shale in the southern Sichuan basin are analyzed by lithologic characteristics, chemical element analysis, reservoir space, gas bearing characteristics, and so on and are compared with domestic and abroad transitional shale gas. The results show that the sedimentary period of transitional shale of Upper Permian Leping Formation has a high paleoproductivity level and deposition rate favorable for the accumulation of organic matter in southern Sichuan basin. It was warm and humid paleoclimatic by Sr, V, Cr, Ni, Co, and other trace elements analysis. According to the experimental test analysis of reservoir characteristics, the organic matter is mainly type Ⅲ kerogen, and the thermal evolution degree is mainly overmature in the reservoir. The reservoir space is mainly of microfractures and micropores. The main types of micropore development are intergranular pore, intragranular pore, and organic pore. Compared with other shale gas regions that form industrial airflow, the study region with large thickness, highly brittle mineral content, high level of organic carbon content, and excellent gas-bearing characteristics, it has favorable conditions for shale gas accumulation. The southern Sichuan basin could be the key area for breakthroughs in the exploration and development of transitional shale gas in the next step.
