Preparation and performance control of ultra-low near-infrared reflectivity coatings with super-hydrophobic and outstanding mechanical properties.

The development of ultra-low near-infrared reflectivity coatings with outstanding engineering properties remains a challenge in laser stealth materials research. Herein, we reported a laser stealth coating with outstanding mechanical properties, super-hydrophobicity, and an ultra-low near-infrared reflectivity for 1.06 μm wavelength.

Analysis and design of an ultra-wide temperature difference very long wave infrared multifunctional imaging spectrometer.

The detection of various cryogenic targets, including the polar cryosphere, high-altitude clouds, and cosmic galaxies through spectral analysis, is a highly valuable area of research. Nevertheless, creating a very long wave infrared (VLWIR) imaging spectrometer capable of detecting these targets presents a significant challenge. In this paper, we introduce a design concept for an ultra-wide temperature difference athermalization VLWIR multifunctional imaging spectrometer.

From heart failure and kidney dysfunction to cardiorenal syndrome: TMAO may be a bridge.

The study of trimethylamine oxide (TMAO), a metabolite of gut microbiota, and heart failure and chronic kidney disease has made preliminary achievements and been summarized by many researchers, but its research in the field of cardiorenal syndrome is just beginning. TMAO is derived from the trimethylamine (TMA) that is produced by the gut microbiota after consumption of carnitine and choline and is then transformed by flavin-containing monooxygenase (FMO) in the liver. Numerous research results have shown that TMAO not only participates in the pathophysiological progression of heart and renal diseases but also significantly affects outcomes in chronic heart failure (CHF) and chronic kidney disease (CKD), besides influencing the general health of populations.

Large numerical aperture off-axis reflective telescope design with a freeform mirror based on aperture expansion strategy.

Currently, the emission of greenhouse gases is one of humanity's leading threats. To accurately and efficiently measure greenhouse gas levels in the atmosphere, we must develop imaging spectrometer systems with larger numerical apertures (NAs). However, designing a telescope with a large NA is difficult in this system.

Analysis and design of a wide-field and large-numerical-aperture compact imaging spectrometer with a freeform surface.

Wide-field-of-view (FoV) Offner imaging spectrometers with freeform surfaces have been studied extensively in recent years. However, a design result with a large numerical aperture (NA) cannot be simultaneously obtained with this layout. We present the concept of a limited system in the tangential direction.

Multiple-Filling-Induced Full-Spectrum Phonon Scattering and Band Convergence Leading to High-Performance n-Type Skutterudites.

Filling guest atoms into the nanovoids of skutterudite compounds provides effective scattering for low-frequency phonons to reduce the lattice thermal conductivity. However, it is still difficult to simultaneously realize the full-spectrum phonon scattering and band engineering in the n-type skutterudites with higher thermoelectric performance. Here, we reveal that the combination of five types of element atoms in the lattice nanovoids brings about dense dislocations, abundant precipitated nanoparticles, and electronic band convergence in the n-type skutterudites.

High-performance wearable thermoelectric generator with self-healing, recycling, and Lego-like reconfiguring capabilities.

Thermoelectric generators (TEGs) are an excellent candidate for powering wearable electronics and the "Internet of Things," due to their capability of directly converting heat to electrical energy. Here, we report a high-performance wearable TEG with superior stretchability, self-healability, recyclability, and Lego-like reconfigurability, by combining modular thermoelectric chips, dynamic covalent polyimine, and flowable liquid-metal electrical wiring in a mechanical architecture design of "soft motherboard-rigid plugin modules." A record-high open-circuit voltage among flexible TEGs is achieved, reaching 1 V/cm at a temperature difference of 95 K.

Analysis method of the Offner hyperspectral imaging spectrometer based on vector aberration theory.

Compact hyperspectral imaging spectrometers with a wide field of view (FoV) have significant application value. However, the aberration field of such imaging spectrometers is sensitive, and varies for different wavelengths when reducing the spectrometer volume. It is difficult to explain the variation in the aberration field using traditional aberration theory.

Design of a compact hyperspectral imaging spectrometer with a freeform surface based on anastigmatism.

Hyperspectral imaging spectrometers with a wide field of view (FoV) have significant application values. However, enhancing the FoV will increase the volume of the imaging spectrometer and reduce the imaging quality, so a wide-FoV spectrometer system is difficult to design. Based on the theory of off-axis astigmatism, we present a method that includes a "prism box," "partial anastigmatism," and a partial differential equation to solve the parameters of a freeform surface.

Metallization and Diffusion Bonding of CoSb-Based Thermoelectric Materials.

CoSb-based skutterudite alloy is one of the most promising thermoelectric materials in the middle temperature range (room temperature-550 °C). However, the realization of an appropriate metallization layer directly on the sintered skutterudite pellet is indispensable for the real thermoelectric generation application. Here, we report an approach to prepare the metallization layer and the subsequent diffusion bonding method for the high-performance multi-filled -type skutterudite alloys.

Microstructure Evolution and Mechanical Properties of Melt Spun Skutterudite-based Thermoelectric Materials.

The rapid solidification of melt spinning has been widely used in the fabrication of high-performance skutterudite thermoelectric materials. However, the microstructure formation mechanism of the spun ribbon and its effects on the mechanical properties are still unclear. Here, we report the microstructure evolution and mechanical properties of La-Fe-Co-Sb skutterudite alloys fabricated by both long-term annealing and melt-spinning, followed by sintering approaches.

Cuff-less and Calibration-free Blood Pressure Estimation Using Convolutional Autoencoder with Unsupervised Feature Extraction.

Monitoring blood pressure (BP) in people's daily life in an unobtrusive way is of great significance to prevent cardiovascular disease and its complications. However, most of the current cuff-less BP estimation methods still suffer from two drawbacks including calibration and tedious feature selection. In this study, we first attempt to validate the feasibility of convolutional autoencoder (CAE) to estimate continuous BP without calibration and hand-crafted feature extraction.