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Elastic carbon materials with high compressibility are ideal candidates for flexible piezoresistive sensors. Carbon nanotubes (CNTs) are promising nanoblocks for fabricating compressible and elasti...

3D carbon aerogels with high compressibility and elasticity hold great promise for applications in piezoresistive sensors and various wearable devices. MXenes are new 2D conductive alternatives to fabricate piezoresistive carbon aerogels. However, it's difficult to obtain MXene-based continuous macrostructures with individually lying MXene nanosheets due to their low aspect ratio. To solve this issue, cellulose nanocrystals (CNCs) are used as a nano-support to connect MXene nanosheets into a lamellar carbon aerogel with not only super mechanical performances but also ultrahigh linear sensitivity. The interaction between MXene and CNCs results in a super stable wave-shaped lamellar architecture that can undergo an extremely high compression strain of 95% and long-term compression (10 000 cycles, at 50% strain). It also displays both extremely high sensitivity (114.6 kPa−1) and wide linear range (50 Pa–10 kPa) that have not been achieved in other carbon aerogels. In addition, the aerogel can detect a tiny pressure change (1.0 Pa). These advantages allow the carbon aerogel to have application in wearable piezoresistive devices for detecting biosignals.

Compressible and conductive materials (CCMs) have important applications in developing pressure sensors for various wearable devices. However, it is a great challenge to fabricate a CCM with superior mechanical properties and ultrahigh linear sensitivity. Herein, we developed a green and effective method to fabricate a lightweight, compressible and conductive aerogel by connecting Ti3C2 nanosheets into continuous and ordered lamellae with a biomass polymer (chitosan). Due to the connecting effect, the lamellae are flexible, highly compressible and elastic as well as structurally stable. These features allow the aerogel to withstand extremely high strain (99%), long-term compression (up to 150 000 cycles), and repeated bending. Furthermore, due to the unique lamellar architecture, the aerogel demonstrates an ultrahigh sensitivity (80.4 kPa−1) and exceptionally wide linear range (within strain of 0.5–70%). In addition, it has low detection limits for tiny strain (0.5%) and pressure (1.0 Pa). Due to these advantages, the aerogel shows potential for application in flexible wearable devices for detecting biosignals.

Facing the growing high data rate and large communication capacity demands, optical communications are widely recognized to be used to implement satellite communications. For a space-based optical backbone network, an appropriately designed protocol stack is important. In this paper, we proposed a protocol stack that is suitable for a space-based optical backbone network. Following this, we then used software to simulate this stack, built a hardware platform to test it, and finally, analyzed the results. The results showed that the proposed protocol stack was well designed to provide efficient control and management of the space-based optical backbone network. It could improve management efficiency by collecting resources and automatically calculating and building route paths. It could also facilitate data forwarding in intermediate satellite nodes with limited source and power, by using an advanced orbiting systems (AOS) frame switching scheme to avoid unnecessary processes, such as unpacking, upper-layer processing and repacking for passing services. The protocol stack could also support the use of unidirectional links to improve the link resource utilization. Finally, it could also provide transparent transmission for different kinds of services.

Methylenetetrahydrofolate reductase (MTHFR), a folate-dependent enzyme, is reportedly involved in several cancer types. The MTHFR C677T polymorphism influences many biological processes, including tumorigenesis. However, the association between the MTHFR C677T polymorphism and breast cancer (BC) subtypes is not fully understood. In this study, the MTHFR C677T polymorphism was genotyped in 490 individuals with or without BC from southwestern China. Analysis of the association between the MTHFR C677T polymorphism and BC revealed that there was a significant association between the MTHFR C677T polymorphism and triple-negative breast cancer (TNBC) (OR = 2.83, 95% CI: 1.12–9.51, P = 0.0401). Furthermore, the MTHFR C677T polymorphism can also serve as a protective factor in luminal A breast cancer (OR = 0.57, 95% CI: 0.34–0.94, P = 0.0258). Evaluation of the association between the MTHFR C677T polymorphism and clinical characteristics indicated that people who suffered from hypertension had an increased risk for BC (OR = 2.27; 95% CI: 1.08–4.6; P = 0.0264), especially TNBC (OR = 215.38; 95% CI: 2.45–84430.3; P = 0.0317). Our results suggest that the MTHFR C677T polymorphism is significantly associated with susceptibility to luminal B breast cancer and TNBC.

The pressure shell seal structure is an important part of the control rod drive mechanism, and it is also one of the key structures to ensure the normal operation, safety and reliability of the reactor. In this paper, a new type of sealing structure of pressure shell of control rod drive mechanism is proposed to meet the requirements of multiple loading and unloading in special marine environment. Compared with the traditional welding connection structure, it has the advantages of fast and convenient operation, easy replacement of sealing components and so on. It can greatly shorten the loading and unloading time of control rod drive mechanism in the refueling process and avoid damage.

Compressible and elastic carbon materials offer many advantages and have promising applications in various electronic devices. However, fabricating carbon materials with super elasticity, fatigue resistance, and high and wide-range linear sensitivity for pressure or strain remains a great challenge. Herein, a facile and sustainable route is developed to fabricate a carbon aerogel with not only superior mechanical performances but also exceptionally high and wide-range linear sensitivity by using chitosan as a renewable carbon source and cellulose nanocrystal as a nanoreinforcement or support. The as-prepared carbon aerogel with wave-shaped layers shows high compressibility, super elasticity, stable strain–current response, and excellent fatigue resistance (94% height retention after 50 000 cycles). More importantly, it demonstrates both an ultrahigh sensitivity of 103.5 kPa–1 and a very wide linear range of 0–18 kPa. In addition, the carbon aerogel has a very low detection limit (1.0 Pa for pressure and 0...

Near-infrared spectroscopy (NIRS) combined with chemometrics analysis was used in this study to qualitatively and quantitatively determine the adulterated Camellia oil. A binary model was constructed for determining both the authenticity and the number of adulterated contents. NIRS combined with support vector machine classification was used to establish a full spectral model and a selected spectral model via competitive adaptive heavy-weighted sampling and backward interval partial least squares. Notably, both of them were proved to be suitable for determining the authenticity of Camellia oil. NIRS combined with support vector machine regression may be used to predict the amount of adulterated content in Camellia oil because of the high model correlation coefficient (R was higher than 99%, and the maximum mean square error was 0.0605).

In the process of stable operation of power transformer, one-point grounding of iron core should be ensured. When two or more points of grounding occur, it will cause transformer operation failure, even burning iron core, affecting the safe operation of the power grid. At present, the monitoring of transformer grounding point mostly adopts the current transformer monitoring mode, only after uploading the detection data to the server, the comparison prompts that manual intervention is needed in the later stage, which increases the processing time and increases the risk of power grid problems. From the point of view of intelligent monitoring, this paper designs an intelligent transformer core grounding monitoring system. When the fault of multi-point grounding is detected, the resistance value of current limiting resistance is calculated immediately according to the magnitude of current, and the series resistance is introduced to limit the current of grounding circuit. At the same time, the fault alarm is given, indicating that manual intervention greatly reduces the occurrence of transformer faults. The processing time reduces the probability of deterioration in case of failure and improves the stability of transformer operation.