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State-of-the-art treatment of such orthopedic diseases as fracture and femoral head necrosis implies the installation of prosthesis or fixed equipment into patients’ injured parts using bone drilling. This study proposes an ultrasonic longitudinal torsion-assisted drilling (ULTAD) technique for biotic bone drilling. A comparative experiment was carried out between conventional drilling and ULTAD drilling in biotic bone, namely porcine femur. These tests proved that under the same drilling parameters, the ultrasonic component in bone drilling could reduce the drilling temperature and forces, improve the material removal by chip breaking, shorten the length of bone debris, and facilitate their discharge. Moreover, the proposed ULTAD technique reduced the number, length, and width of microcracks in the borehole wall, thus protecting the drilled biotic bone from internal damage.

Developing efficient and long-lasting cathode catalysts is crucial for preparing high-performance lithium–sulfur (Li–S) batteries. Here, we designed and synthesized hierarchical, gradient, and multi-dimensional Co@NCNN armor catalysts by pyrolyzing g-C3N4 in the presence of cobalt nitrate. The unique structure of the Co@NCNN armor catalysts combines 0D Co nanoparticles and outer carbon protective shells, which adsorb and confine LiPSs, as well as 1D carbon nanotubes and 2D carbon nanosheets, which enhance the sulfur load and block LiPS diffusion, respectively. XANES and XPS analysis showed that Co–Co bonds with different Co valence states are the main catalytic sites for LiPSs. In situ XRD experiments and Li2S deposition tests demonstrated that the Co@NCNN armor catalysts can accelerate the liquid–solid conversion process, resulting in an initial discharge capacity of 1388.9 mA h g−1 at 0.5 C, an excellent area capacity of 5.05 mA h cm−2 and a sulfur load of 6.1 mg cm−2. More importantly, the robust carbon layer protects the highly active inner cobalt nanoparticles, enabling them to perform 1000 cycles at a current density of 7 C, with a capacity decay rate of 0.048% per cycle, and maintain stability over a wide temperature range of 0 to 60 °C. [ABSTRACT FROM AUTHOR]

With the widespread use of machine learning (ML) technology, the operational efficiency and responsiveness of power grids have been significantly enhanced, allowing smart grids to achieve high levels of automation and intelligence. However, tree ensemble models commonly used in smart grids are vulnerable to adversarial attacks, making it urgent to enhance their robustness. To address this, we propose a robustness enhancement method that incorporates physical constraints into the node-splitting decisions of tree ensembles. Our algorithm improves robustness by developing a dataset of adversarial examples that comply with physical laws, ensuring training data accurately reflects possible attack scenarios while adhering to physical rules. In our experiments, the proposed method increased robustness against adversarial attacks by 100% when applied to real grid data under physical constraints. These results highlight the advantages of our method in maintaining efficient and secure operation of smart grids under adversarial conditions. [ABSTRACT FROM AUTHOR]

In this article, the laser-assisted ultrasonic vibration dressing technique was applied to the cubic boron nitride (CBN) grinding wheel to study the effect of various process parameters (namely, laser power, dressing depth, feed rate, and grinding wheel speed) on the grinding force, surface quality, and morphological evolution of CBN abrasive particles. The results showed that abrasive particles’ morphology mainly undergoes micro-crushing, local crushing, large-area crushing, macro-crushing, and other morphological changes. The dressing force can be effectively reduced by controlling the dressing process parameters. Besides, grinding tests are performed on the grinding wheel after dressing to reveal specimens’ surface quality. Excellent grinding characteristics and grinding quality of the grinding wheel were obtained by the proposed technique with the optimized process parameters.

Flexible, breathable, and sensitive sensors have significant applications in gas detection, healthcare, body motion tracking, and more. However, most current flexible sensors are frequently built with polymer substrates with restricted flexibility, poor gas permeability, and poor temperature tolerance, thus limiting their multifunctional applications in wearable electronics. Herein, an easy, universal, and effective two-spinneret electrospinning approach is developed to construct an all-inorganic self-supporting multifunctional nanofiber membrane with high flexibility and gas permeability, consisting of an amorphous SiO2 nanofiber (NF) substrate layer and interwoven PdO–SnO2–SiO2 NF sensing component. The highly flexible and structurally stable amorphous SiO2 NFs are embedded randomly within the PdO–SnO2 NF sensing layer as a skeleton, effectively preventing the cracking and detachment of the sensing layer. Gas-sensing results demonstrate flexible room-temperature sensing towards ppb-level NO2 with excellent sensitivity, selectivity, and cycling stability over 3200 cycles. Additionally, SiO2 NFs endow the flexible sensor with a unique high-temperature sensing ability to selectively monitor NO2 in a fire scenario. Real-time monitoring of breath-related health signals also shows multifunctional applications with high sensing performance. The results provide an important advance towards the universal construction of flexible and breathable multifunctional membranes for high-performance flexible and wearable sensing applications. [ABSTRACT FROM AUTHOR]

Kiwi wine (KW) is tipically made by fermenting juice from peeled kiwifruit, resulting in the disposal of peel and pomace as by-products. However, the peel contains various beneficial compounds, like phenols and flavonoids. Since the peel is edible and rich in these compounds, incorporating it into the fermentation process of KW presents a potential solution to minimize by-product waste. This study compared the aroma and taste profiles of KW from peeled (PKW) and unpeeled (UKW) kiwifruits by combining intelligent sensory technology, GC-MS, and 1H-NMR. Focusing on aroma profiles, 75 volatile organic compounds (VOCs) were identified in KW fermented with peel, and 73 VOCs in KW without peel, with 62 VOCs common to both. Among these compounds, rose oxide, D-citronellol, and bornylene were more abundant in UKW, while hexyl acetate, isoamyl acetate, and 2,4,5-trichlorobenzene were significantly higher in PKW. For taste profiles, E-tongue analysis revealed differences in the taste profiles of KW from the two sources. A total of 74 molecules were characterized using 1H-NMR. UKW exhibited significantly higher levels of tartrate, galactarate, N-acetylserotonin, 4-hydroxy-3-methoxymandelate, fumarate, and N-acetylglycine, along with a significantly lower level of oxypurinol compared to PKW. This study seeks to develop the theoretical understanding of the fermentation of kiwifruit with peel in sight of the utilization of the whole fruit for KW production, to increase the economic value of kiwifruit production. [ABSTRACT FROM AUTHOR]