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We have evaluated the ensemble empirical mode decomposition (EEMD) and stacking model for borehole seismic-data denoising. The borehole records collected by distributed acoustic sensing (DAS) technology have multitype noise contamination, and it is difficult to attenuate these noises while recovering the seismic waves well. We first perform EEMD on the seismic data to obtain the signal-to-noise modal components, then extract the time and frequency information of the decomposed modes using six feature factors, and finally introduce an ensemble learning method to classify the acquired modal features effectively. Stacking is the ensemble learning technique we used in our study. This technique integrates several diverse basic ensemble models using the meta-learning strategy and constructs a highly integrated framework with superior performance and good generalization. In addition, the basic ensemble models consist of many decision tree classifiers following two different ideas of parallelization and serialization. The feature extraction process provides sufficient DAS feature data for the training process of the framework. Synthetic and real experimental results demonstrate that the stacking integration framework effectively separates the signal-to-noise modal features of the borehole DAS records. Furthermore, the EEMD-stacking method performs better than wavelet transform, intrinsic time-scale decomposition, robust principal component analysis, k-means singular value decomposition, and median filtering on the denoising task.

The designed WBE breaks the trade-off between water evaporation and salt resistance, achieving ultrahigh water evaporation capacity (3.02 kg m−2 h−1) and long-term salt resistance (continuous 100 h in 20 wt% brine) under 1 sun irradiation.

Three-dimensional (3D) elastic aerogels enable diverse applications but are usually restricted by their low thermal and electrical transfer efficiency. Here, we demonstrate a strategy for fabricating the highly thermally and electrically conductive aerogels using hybrid carbon/ceramic structural units made of hexagonal boron nitride nanoribbons (BNNRs) with in situ-grown orthogonally structured graphene (OSG). High-aspect-ratio BNNRs are first interconnected into a 3D elastic and thermally conductive skeleton, in which the horizontal graphene layers of OSG provide additional hyperchannels for electron and phonon conduction, and the vertical graphene sheets of OSG greatly improve surface roughness and charge polarization ability of the entire skeleton. The resulting OSG/BNNR hybrid aerogel exhibits very high thermal and electrical conductivity (up to 7.84 W m

Solar energy-facilitated materials are promising to solve energy problems by converting clean solar energy to thermal energy. However, heat loss of photothermal materials still limits the photothermal conversion phenomenon. Herein, we designed bio-inspired hollow carbon microtubes (HCMTs) by one-step carbonization of renewable cotton fibers, which can avoid the complex preparation procedures of the template method. Similar to polar bears, the hollow construction can efficiently reduce heat loss, which improves the utilization of light and photothermal property. The HCMTs can be applied on a variety of substrates to obtain multifunctional photothermal protective coatings. The temperature of the coating can rapidly warm up to 97.7 °C under 1 kW/m

Because of the high synthesis cost, strong chemical inertness, complex process, and easy to endanger environment of traditional carbon-based nanolubricant additives, the development of its application in lubrication is limited. Therefore, a new type of lubricant additive with low cost, high yield, high performance, and environmental protection is urgently needed. Herein, a kilogram-scale carbon dots (CDs) lubricant additive was prepared by a simple and green one-step reaction of aldol condensation, which showed excellent lubricating properties in water and sunflower oil. The tribological properties of the CDs lubricant additive at different concentrations, loads, and speeds were systematically studied. The results show that the average friction coefficient of water is significantly reduced by 75% by a CDs lubricant additive. In particular, CDs not only exhibited excellent service life and lubrication stability during friction but also kept the friction coefficient change rate of sunflower seed oil close to 0 within 500 min. According to the tribological evaluation and wear surface analysis, the lubrication mechanism of CDs was attributed to their own morphological characteristics and abundant oxygen-containing functional groups on the surface. In the friction process, the charge adsorption effect, the adsorption protective film, and the hydrogen bonding layer are generated, which play an essential role in obvious antiwear and friction reduction. Therefore, this work provides a reference for the preparation of high-performance and high-yield lubricant additives.

An intelligent drug delivery platform based on the hybrids of mesoporous silica nanoparticles (MSN), sodium hyaluronate (HA), chitosan (CS) and oxidized sodium carboxymethyl cellulose (oxCMC) is developed, which can be used for dual-responsive dual-drug delivery. Hydrophilic cytarabine (Cyt) is first loaded into the mesopores of the aminated MSN (NH

Ferroptosis is a novel cell death form against drug-resistance through bypassing apoptosis, but its therapeutic efficacy triggered by traditional iron-based nanomaterials or classic drug inducers has been far from satisfactory due to the high glutathione (GSH) level in tumor cells and insufficient lipid peroxide production. Here we reported a combinational ferroptosis/apoptosis therapy approach by depleting GSH and downregulating GPX4 to disrupt redox homeostasis and amplify ferroptosis-related oxidation effect. In this study, we developed a ROS-responsive serum-resistant nanoparticles with a thioketal-crosslinked fluorinated polyethyleneimine PEI 1.8K (TKPF) as the core and wrapped with hyaluronic acid (HA) as the shell (TKPFH NP) to co-deliver shGPX4 and shMTHFD2 plasmids for cancer treatment. The highly efficient and tumor-selective gene carrier TKPFH NPs revealed outstanding transfection efficiency (~100 %) and sustained the efficiency (~50 %) even in media containing 90 % FBS. TKPFH NPs actively targeted CD44 receptors mediated by HA to enable efficient uptake by tumor cells and experienced surface charge conversion to induce subsequently lysosomal escape. Then the TKPF NPs were effectively disintegrated by the abundant ROS in cancer cells, which facilitated release of plasmids and avoided the cytotoxicity of cationic polymers. shGPX4 plasmid induced ferroptosis by producing ROS and lipid peroxides via downregulating GPX4, while shMTHFD2 triggered apoptosis by modulating NADPH/NADP and depleting GSH of the cancer cells. Moreover, GSH consumption resulted by shMTHFD2 indirectly suppressed GPX4 and further augmented ferroptosis, showing synergistic anticancer effect against B16-F10 cells. Taken together, the rationally designed dual-gene loaded TKPFH NPs provided a safe and high-performance platform aimed for enhanced ferroptosis-apoptosis combined anticancer efficacy based on gene therapy.

Despite of the hazardous risk of Pb2+ leakage, lead dioxide has been attributed as a quasi-ideal anode material with high oxygen evolution potential, excellent conductivity, good stability and low cost in electrochemical oxidation wastewater treatment technique. In this study, a novel Ti/PbO2 anode was fabricated by embedding raw materials that are readily and cheaply available, i.e., hairs. The structure-activity relationship of the new electrode was firstly revealed by material and electrochemical characterizations. Then different levels of pollutants (azo dye, phenol and maleic acid) were used to investigate the electrochemical oxidation performance of the new electrode. Finally, the accelerated electrode lifetime and Pb2+ leakage tests were carried out. Results showed that the embedded hairs changed the preferential crystallographic orientation of PbO2 and decreased the grain size. Hairs introduced additional roughness and active sites, and decreased the electrode impedance, especially under 5 mg/cm2 of embedding amount. The removal efficiencies of different target pollutants were enhanced more or less by embedding appropriate amount of hairs, depending on the current density, but loading excessive hairs had a negative effect. The accumulation of intermediate products during phenol degradation was also changed by the hairs. The new electrode could undergo ∼550 h of harsh electrolysis. It is also relieved that the Pb2+ leakage was found to be suppressed during this long-term electrolysis process.

Scholars believe that computational thinking is one of the essential competencies of the 21st century and computer programming courses have been recognized as a potential means of fostering students’ computational thinking. In tradition instruction, PFCT (problem identification, flow definition, coding, and testing) is a commonly adopted procedure to guide students to learn and practice computer programming. However, without further guidance, students might focus on learning the syntax of computer programming language rather than the concept of solving problems. This study proposes a peer-assessment-supported PFCT (PA-PFCT) approach for boosting students’ computer programming knowledge and computational thinking awareness. A quasi-experiment was conducted on a computer programming course in a high school to evaluate its influence on students’ learning achievement, computational thinking awareness, learning motivation, and self-efficacy. An experimental group of 51 students learned with the proposed approach, while a control group of 49 students learned with the traditional PFCT (T-PFCT) approach. The experimental results show that the proposed approach significantly enhanced the students’ computational thinking awareness, learning motivation, and self-efficacy, while not having significant impacts on their computer programming knowledge test scores.

We report on a free-standing 3D-printed Si/PEDOT:PSS/PEG electrode based on silicon nanoparticles (Si) as an active material for lithium-ion batteries (LIBs) that are fabricated by 3D printing

Designing a transformable nanosystem with improved tumor accumulation and penetration by tuning multiple physicochemical properties remains a challenge. Here, a near-infrared (NIR) light-driven nanosystem with size and charge dual-transformation for deep tumor penetration is developed.

A systematic insight into the role of SiO2 as a protective layer in realizing uniform Li-ion deposition is proposed.