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筛选条件 : 物理科学与技术学院
Dong Shu; Chentao Tan; Yue Zhang; Lu Gan; Roger Ruan; Leilei Dai
International Journal of Biological Macromolecules, 2025 291 - SCIE

摘要 : Nanocellulose stands out in numerous applications due to its excellent properties. Yet, achieving its preparation in a cost-effective, efficient, and environmentally benign manner remains challenging. This study introduces a green synthesis approach by employing a non-polluting solid acid, combined with a cellulase enzyme, for nanocellulose production. We explored the impact of varying the addition sequence of solid acid and cellulase on nanocellulose yield. Experimental results showed that under optimal cellulase hydrolysis conditions, solid acid hydrolysis yielded 41.3 % nanocellulose, whereas cellulase hydrolysis resulted in a 27.1 % yield. In co-treatment experiments, with the following process steps: 1) sequential hydrolysis with solid acid, followed by cellulose (SA-E); 2) simultaneous hydrolysis with solid acid and cellulase (SA + E); 3) cellulase followed by solid acid hydrolysis (E-SA). the nanocellulose yields were: 73.37 %, 70.43 %, and 57.21 %, respectively. These results proved a synergistic effect between solid acid and cellulase in both SA-E and SA + E scenarios. In addition, the synergistic mechanism between solid acid and cellulase was proposed. This approach presents a highly promising strategy for achieving high yields of nanocellulose.

Jidong Jia; Tianwei Zhang; YinLin Lu; JingYuan Xu; Xingzhi Wu; Yinglin Song
Journal of Photochemistry and Photobiology A: Chemistry, 2025 459 - SCIE

摘要 : For multi-branched molecules, intramolecular cooperative effect can significantly enhance the molecular nonlinear optical absorption. Three triphenylamine-cored compounds ( N1, N2 and N3 ) with three branches are synthesized to study the cooperative and anti-cooperative effect of electron transition in the excited state on two-photon absorption (TPA) and excited state absorption (ESA). Molecular polarization of these multi-branched triphenylamine derivatives is regulated by changing the molecular symmetry and the planarity of peripheral branches, to regulate their charge distribution and electron transition characteristics in the excited state. Here, we show that due to electronic coupling and interaction between certain branches, the asymmetric distribution of electron clouds in the excited states of these multi-branched molecules will lead to an enhancement of their TPA and ESA cross-sections, which is known as the cooperative effect of electron transitions. On the contrary, electronic coupling and interaction among all branches will lead to a highly symmetric distribution of electron clouds in the excited states of these multi-branched molecules, which will cause anti-cooperative effects and result in significant attenuation of TPA and ESA cross-sections.

Zenghua Cai; Chunlan Ma
Applied Physics Letters, 2025 126 (2) - EI SCIE

摘要 : SrTiO3 (STO) displays a broad spectrum of physical properties, including superconductivity, ferroelectricity, and photoconductivity, making it a standout semiconductor material. Despite extensive research, the oxygen partial pressure-dependent conductivity in STO has remained elusive. This study leverages first-principles calculations and systematically investigates the intrinsic defect properties of STO. The results reveal that VO, VSr, and TiSr are the dominant intrinsic defects, influencing STO's conductivity under varying O chemical potentials (oxygen partial pressures). Under O-poor condition, VO is the predominant donor, while VSr is the main acceptor. As the oxygen pressure increases, TiSr emerges as a critical donor defect under O-rich conditions, significantly affecting the conductivity. Additionally, the study elucidates the abnormal phenomenon where VTi, typically an acceptor, exhibits donor-like behavior due to the formation of O-trimer. This work offers a comprehensive understanding of how intrinsic defects tune the Fermi level, thereby altering STO's conductivity from metallic to n-type and eventually to p-type across different O chemical potentials. These insights resolve the long-standing issue of oxygen partial pressure-dependent conductivity and explain the observed metallic conductivity in oxygen-deficient STO.

Zhaohuan Zhu; Feng Wu; Wenqing Sun; Quanying Wu; Feng Liang; Wuhan Zhang
Electronics, 2025 14 (2) - SCIE

摘要 : Autonomous driving vehicles have strong path planning and obstacle avoidance capabilities, which provide great support to avoid traffic accidents. Autonomous driving has become a research hotspot worldwide. Depth estimation is a key technology in autonomous driving as it provides an important basis for accurately detecting traffic objects and avoiding collisions in advance. However, the current difficulties in depth estimation include insufficient estimation accuracy, difficulty in acquiring depth information using monocular vision, and an important challenge of fusing multiple sensors for depth estimation. To enhance depth estimation performance in complex traffic environments, this study proposes a depth estimation method in which point clouds and images obtained from MMwave radar and cameras are fused. Firstly, a residual network is established to extract the multi-scale features of the MMwave radar point clouds and the corresponding image obtained simultaneously from the same location. Correlations between the radar points and the image are established by fusing the extracted multi-scale features. A semi-dense depth estimation is achieved by assigning the depth value of the radar point to the most relevant image region. Secondly, a bidirectional feature fusion structure with additional fusion branches is designed to enhance the richness of the feature information. The information loss during the feature fusion process is reduced, and the robustness of the model is enhanced. Finally, parallel channel and position attention mechanisms are used to enhance the feature representation of the key areas in the fused feature map, the interference of irrelevant areas is suppressed, and the depth estimation accuracy is enhanced. The experimental results on the public dataset nuScenes show that, compared with the baseline model, the proposed method reduces the average absolute error (MAE) by 4.7–6.3% and the root mean square error (RMSE) by 4.2–5.2%.

Cuicui Hu; Fang Tang; Lina Jiang; Yang Chen; Haifeng Chen; Zilu Xia
Physica B: Condensed Matter, 2025 696 - EI SCIE

摘要 : Fe 3 GaTe 2, with intrinsic magnetism at ambient temperature and high perpendicular magnetic anisotropy, is a promising van der Waals material for 2D-materials-based spintronic devices. Herein, we report the anisotropic magnetocaloric effects and magnetic critical phenomena in Fe 3 GaTe 2 single crystal. Owing to the large anisotropy, magnetic entropy change ( − Δ S M ) shows anisotropic character with − Δ S M max of 1.67 J kg −1 K −1 along the c axis and 1.11 J kg −1 K −1 in the ab plane under field change of 5 T. The rotating Δ S M from the ab plane to the c axis reaches 0.67 J kg −1 K −1 at magnetic field of 5 T. By carefully fitting the − Δ S M max and relative cooling power (RCP), we determine their relationships to be − Δ S M max ∝ H n ( n = 0.694(1)) and R C P ∝ H m ( m = 1.301(3)) for the magnetic field along the c -axis. Further analysis of critical behavior near T C reveals critical exponents β = 0.41(1) at T C = 341.5(1) K, γ = 1.01(1) at T C = 341.6(3) K, and δ = 3.67(15) at T C = 340 K, indicating a three-dimensional complex magnetic exchange.

Yuxin Qin; Xiaoliang Zhang; Shiting Zhou; Yangyang Wang; Gaoyuan Chen; Chen-Min Dai
The Journal of Chemical Physics, 2025 162 (1) - EI SCIE

摘要 : Despite the conventional view of liquid aluminum (l-Al) as a simple metal governed by the free-electron model, it exhibits unique bonding characteristics. This study uncovers a gradual transition from free electron to electride behavior in l-Al at high pressure and temperature, forming a type of two-component liquid where atomic and electride states coexist. The proportion of electride increases with pressure and temperature until reaching saturation, leading to notable changes in the pair-correlation function and coordination number of l-Al at saturation pressure. Furthermore, this electride transition was found to profoundly impact the thermodynamic and dynamic properties, as evidenced by anomalous crossovers in the isothermal bulk modulus, thermal expansivity, heat capacity, sound speed, and self-diffusion coefficient correlated with varying pressure and temperature. The finding of the anomalous behavior of l-Al described in this work will deepen our understanding of the electronic structure and also lay ground work for interpreting and predicting new physical and chemical behavior under extreme conditions.

Jingyun Zou; Lei Tang; Lixing Kang
ACS Nano., 2025 -1 - EI SCIE

摘要 : Heating techniques have underpinned the progress of the material and manufacturing industries. However, the explosive development of nanomaterials and micro/nanodevices has raised more requirements for the heating technique, including but not limited to high efficiency, low cost, high controllability, good usability, scalability, universality, and eco-friendliness. Carbothermal shock (CTS), a heating technique derived from traditional electrical heating, meets these requirements and is advancing at a high rate. In this review, the CTS technique, including the material to support CTS, the power supply to generate CTS, and the method to monitor CTS, is introduced, followed by an overview of the progress achieved in the application of CTS, including the modification and fabrication of nanomaterials as well as many other interesting applications, e.g., soldering/welding of micro- and macroscopic carbon materials, sintering of ceramic electrolytes, recycling of Li-ion battery, thermal tips, actuators, and artificial muscle. Problems and challenges in this area are also pointed out, and future developing directions and prospects are presented.

Du Li; Chenyu Zhao; Xuliang Zhang; Xinyu Zhao; Hehe Huang; Huifeng Li
Advanced materials, 2025 -1 - EI SCIE

摘要 : Formamidinium lead triiodide (FAPbI3) perovskite quantum dot (PQD) are promising candidate for high-performing quantum dot photovoltaic due to its narrow bandgap, high ambient stability, and long carrier lifetime. However, the carrier transport blockage and nonradiative recombination loss, originating from the high-dielectric ligands and defects/trap states on the FAPbI3 PQD surface, significantly limit the efficiency and stability of its photovoltaic performance. In this work, through exploring dual-site molecular ligands, namely 2-thiophenemethylammonium iodide (2-TM) and 2-thiopheneethylammonium iodide (2-TE), a dual-phase synergistic ligand exchange (DSLE) protocol consisting of both solution-phase and solid-state ligand engineering is demonstrated. The DSLE strategy effectively replaces the native long insulating ligands and simultaneously passivate surface defects in hybrid FAPbI3 PQDs, leading to enhanced electronic coupling for efficient charge transport. Consequently, the FAPbI3 PQD solar cell based on DSLE strategy achieves a notable enhanced efficiency from 15.43% to 17.79% (2-TM) and 18.21% (2-TE), respectively. Besides, both 2-TM and 2-TE engineered devices exhibit enhanced stability, maintaining over 80% of its initial efficiency after aging in ambient environment (20-30% humidity, 25 °C) for over 1400 h. It believes these findings will provide a new protocol to precisely regulate the surface chemistry of hybrid PQDs toward high-performance optoelectronic applications.

Di Wang; Jinlei Zhang; Yukang Liu; Zijing Guo; Ziyang Fu; Hengdong Ren
Nano Letters, 2025 -1 - EI SCIE

摘要 : While the highest-performing memristors currently available offer superior storage density and energy efficiency, their large-scale integration is hindered by the random distribution of filaments and nonuniform resistive switching in memory cells. Here, we demonstrate the self-organized synthesis of a type of two-dimensional protonic coordination polymers with high crystallinity and porosity. Hydrogen-bond networks containing proton carriers along its nanochannels enable uniform resistive switching down to the subnanoscale range. Leveraging such nanochannel arrays, we achieve logic operations of graphical gate circuits with negligible leakage and sneak path currents over areas ranging from 0.5 μm × 0.5 μm to 20 nm × 20 nm, providing the smallest building blocks to date for large-scale integration. The nonvolatile resistive switching exhibits high mobility (∼0.309 cm2 V-1 s-1), a large on/off ratio (∼103), and ultrahigh-density data storage (∼645 Tbit/in2), even within a trilayer (∼4.01 nm). An ultrahigh-precision artificial retina with integrated convolutional neural network calculations is demonstrated, enabling facial and color recognition capabilities.

Cong Li; Ross T Howie; Hongliang Dong; Wenge Yang; Hongwei Sheng; Xiaozhi Yan
Nano Letters, 2025 -1 - EI SCIE

摘要 : The vibron behavior of hydrogen bears significant importance for understanding the phases of solid hydrogen under high pressure. In this work, we reveal an unusual high-pressure behavior of hydrogen confined within nanopores through a combination of experimental measurements and theoretical calculations. The nanoconfined hydrogen molecules retain an hcp lattice up to 170 GPa, yet significant deviations from the vibrational characteristics of bulk hydrogen are observed in the primary vibrons of both Raman and infrared spectra. This lowered vibron peak is linked to the disorder of the hydrogen molecules with longer bonds and enhanced intermolecular interactions at the interface. Further investigation reveals that this nanoscale confinement leads to a considerable decrease in the band gap of solid hydrogen, potentially facilitating band gap closure at considerably lower pressures. Our findings provide crucial insights into the behavior of solid hydrogen under spatial nanoconfinement, paving the way for novel explorations into hydrogen metallization.