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The biological world serves as a vast reservoir of inspiration for human innovation, particularly in the realm of robotics designed to navigate intricate granular environments. Among these creatures adept at burrowing, the mole stands out due to its exceptional body structure and unparalleled efficiency, surpassing most engineering burrowing systems. Consequently, the mole serves as an ideal model for designing highly efficient burrowing robots. This study introduces a mole‐inspired robot burrowing with forelimbs, specifically designed for planetary soil exploration. By closely examining the distinctive body morphology of moles, a forelimb burrowing mechanism is devised through biomimetic mapping, and its kinematics is thoroughly analyzed. A robot prototype is developed and an experimental setup is constructed to evaluate its burrowing performance. A series of tests are conducted to assess the capabilities of the robot, including forelimb burrowing, robot crawling, and robot burrowing. The results demonstrate that the proposed mole‐inspired burrowing robot is capable of crawling and burrowing to a certain depth using its forelimbs. Although it exhibits some upward displacement, this issue can be mitigated by modifying the head configuration and adjusting the forelimb posture to effectively overcome the vertical stress and lift force exerted by granular soils due to intensity gradient. [ABSTRACT FROM AUTHOR]

Rice adaptation to low temperatures involves changes in their genetic and physiological architecture, caused by complex and variable transcriptional regulatory networks to regulate between growth and stress resistance. Overwintering rice survives cold winter and germinates the following spring. The perennial and cold‐tolerant properties present great potential regarding rice breeding and food security. In this study, the cold‐tolerant overwintering cultivar rice, "glutinous rice 89‐1" (Gr 89‐1), and an indica cultivar rice, "R07," were placed at 4°C at the tillering stage and sampled at 0, 12, 24, and 96 h, and recovery 7 days. Physiological indicators of each sample were measured, and transcriptome analysis was performed. The results revealed that the overwintering cultivar rice Gr 89‐1 exhibited a pattern of physiological parameters consistent with the cold‐tolerant phenotype, less membrane damage accumulation and water loss with increasing duration of low temperature, and a stable increase in peroxidase activities, catalase activities, and soluble sugar content. Transcriptome analysis of two cultivars at 0, 12, and 24 h under 4°C revealed different gene expression patterns to low temperatures. Compared with R07, gene ontology terms of nuclear lumen, endomembrane system, organelle membrane, and envelope were enriched in Gr 89‐1, suggesting an alteration of membrane composition during cold acclimation. Specific upregulated transcription factors and cold‐tolerance regulators indicated a coordinated response between signal transduction, energy regulation, cell cycle, and circadian rhythm, which might help maintain cell homeostasis and improve Gr 89‐1 survival under cold stress. Two candidate genes OsETR3 and NAC78 were screened out, they significantly upregulated at 12 and 24 h of cold treatment in Gr 89‐1 and were higher than R07, and they were involved in cell wall remodeling and endoplasmic reticulum homeostasis under stress, respectively, which may relate to the cold‐tolerant trait of Gr 89‐1. [ABSTRACT FROM AUTHOR]

Temperature and thermal stress are crucial factors affecting the working performance and thermal safety of lithium‐ion batteries (LIBs). During the discharge process of the battery, the temperature increases. The thermal expansion stress caused by the entropy heat and the ohmic heat can lead to the battery's lifetime reduction and even thermal safety issues. Herein, based on the coupled electrochemical model, the LIB's thermal behavior and thermal stress distribution at a 1C discharge rate are simulated and analyzed. The results show that the temperature distribution inside the battery is mainly affected by the heat exchange surface and the position of the tabs during the discharging process, in which the localized high‐temperature region occurs in the positive tab. The thermal stress inside the battery enhances rapidly at both the beginning and end of the discharging process while increasing slowly in the middle. [ABSTRACT FROM AUTHOR]

A deep extraterrestrial drilling mission potentially adds a new level of complexity, and it is crucial to understand the associated challenges. To cope with China's Chang'E 5 mission to return subsurface regolith samples from the Moon, a series of laboratory tests were performed to validate the lunar robotic drilling from 2015 to 2018. The tests took place in a simulated thermal‐vacuum regolith environment, a highly relevant lunar analog site. Force and temperature sensors were integrated into a 2‐m class dry auger coring drill to assess the mechanical and thermophysical status of the sampling process. The operation of the entire testing system was automated, covering regolith penetration and data collection and storage. The science team used sensing data to characterize the subsurface geologic strata, assess the conditions of the drilling robot, and direct the sampling strategy. This experiment represents an essential first step in understanding the technology and operational requirements for lunar drilling and sampling mission. Many laboratory tests have helped guide the design and implementation of the highly successful lunar regolith‐sampling task in the Chang'E 5 mission. This paper documents the experimental system design, highlighting some critical design criteria and design tradeoffs. It also discusses the results of laboratory testing and lists some of the key technological lessons learned. [ABSTRACT FROM AUTHOR]

A series of novel monodisperse, well-defined molecules with a pyridine core and carbazole arms were synthesized by simple procedures with Iodo-reaction and . Their structures were confirmed by IR, 1H NMR, 13C NMR, and elementary analysis. Moreover, the fluorescence spectra showed that these compounds exhibited strong fluorescence with the maximum wavelengths ranging from 373 to 385 nm. [ABSTRACT FROM AUTHOR]