查找使用阿拉丁产品的科研文献

Vanadium oxide as an electron buffer to stabilize palladium for electrocatalytic hydrodechlorination

Meiqin Shi,Yifei Ren,Shuyuan Xu,Xiaofeng Xu,Fanfei Sun,Yuanbin She

The application of Pd catalysts is generally limited by their cost and lower stability. In this study, a series of Pd-based catalysts were prepared using vanadium compounds as supports and applied for electrocatalytic hydrodechlorination (EHDC) of 4-chlorophenol (4-CP). The Pd/VOx/C-700 catalyst demonstrated enhanced EHDC performance, including an efficiency of 92%, which is comparable to that of commercial Pd/C, and it was improved to 97% after 18 h of electrolysis, thus providing excellent durability. By combining characterization results and electron density difference (EDD) calculations, it was found that vanadium compounds with various structures enable the tuning of the chemical state and electronic structure of Pd. The multi-valent vanadium–oxygen structure can work as a buffer to facilitate the optimization of the electronic structure of Pd and stabilize its optimal electronic configuration.

Solvothermal synthesis of wire-like SnxSb2Te3+x with an enhanced thermoelectric performance

Heng Quan Yang,Lei Miao,Cheng Yan Liu,Xiao Yang Wang,Ying Peng,Ai Juan Zhang,Xiao Yuan Zhou,Guo Yu Wang,Chao Li,Rong Huang

Nanostructured tellurides have attracted increasing attention in thermoelectric applications for waste heat recovery and cooling devices. Here, we report on the synthesis of wire-like SnxSb2Te3+x (x = 0, 0.02 and 0.05) nanoparticles using elemental precursors in EG. The enhanced thermoelectric performance was achieved in alloyed samples due to the increase of carrier population in heavy valence band valleys by incorporating Sn2+ at the Sb3+ sublattice, enabling the simultaneous realization of low electrical resistivity along with a high Seebeck coefficient as well as the decline of thermal conductivity. Thus a boosted power factor and low thermal conductivity lead to the highest ZT value of 0.58 at 150 °C in the Sn0.02Sb2Te3.02 sample. Our research offers a general wet-chemical route for the preparation of one-dimensional nanomaterials and probably promotes the practical thermoelectric applications of Sb2Te3-based materials at low temperatures.

An energy-saving structural optimization strategy for high-performance multifunctional graphene films

Ping He,Yu Zhang,Zhenguo Wang,Peng Min,Zhiming Deng,Lulu Li,Lvxuan Ye,Zhong-Zhen Yu,Hao-Bin Zhang

Graphene has been widely studied for its excellent properties of outstanding conductivity, strength , and flexibility. However, interlayer defects formed during the macroscopic assembly of graphene nanosheets will severely degrade the performance of graphene films. Herein, a strategy combined with trace carboxyl graphene oxide (GO), mild reduction, and chemical crosslinking is employed to minimize the interlayer defects for enhancing both the conductivity and mechanical strength of graphene films. The trace carboxyl feature of GO allows nanosheets to assemble orderly into highly oriented GO films . Subsequently, the mild chemical reduction preserves the highly oriented and packed microstructure. Coupling with further crosslinking by introducing conjugated molecules with pyrene terminal groups (1-pyrene butyric acid-1,6-hexane diamine, PHD) to provide extra π-π bonds, both the mechanical strength and conductivity of graphene films are improved to 548.4 MPa and 1.7 × 10 5  S m −1 , respectively. In addition, the graphene film with only ∼2 μm in thickness possesses an excellent electromagnetic interference shielding effectiveness (EMI SE) of ∼40 dB and a specific shielding effectiveness of up to 74 278 dB cm 2  g −1 in a wide frequency range of 8.2–40.0 GHz. Thus, this study provides an energy-saving fabrication route for mechanically strong, effective thermal management and EMI shielding films.

An algorithm for ATM recognition of spliced money based on image features

Wang Zhiyang

According to the problem of spliced money in ATM (Automatic Teller Machine), the paper puts forward a template matching algorithm for recognition of left and right numbers based on one-dimensional gray scale projection. First it uses the Canny boundary detection algorithm to separate the banknote boundary from the R component image, and then preprocesses the image to make the subsequent processing easier; secondly applies the predefined location to divide the area of left and right numbers; thirdly calculates the one-dimensional gray scale projection curves of left and right numbers, based on which every character or number is divided; finally carries out the operation of template matching to obtain correlation coefficients of every character or number, comparing which with threshold it judges whether the left and right numbers are matched. For the transparent tape attached to the spliced money, a method based on the difference in object reflectivity to recognize the tape is designed. First it highlights the characteristics of the tape by preprocessing and binary morphological analysis of the B component image. Finally, it judges whether there is transparent tape on the surface of the banknote according to the set threshold value. Experimental results show that both number matching and tape detection can be completed, and algorithm can correctly recognize spliced money. The correct recognition rate of the algorithm reaches 100%, and the false positive rate、false negative rate are both 0. The processing is fast and simple, which meets the requirements of ATM.

Bionic MXene based hybrid film design for an ultrasensitive piezoresistive pressure sensor

Jinfeng Yan,Yanan Ma,Gang Jia,Sairao Zhao,Yang Yue,Feng Cheng,Chuankun Zhang,Minglei Cao,Yongchen Xiong,Peizhi Shen,Yihua Gao

An ultrasensitive bionic MXene based piezoresistive pressure sensor was rationally designed and realized by molding the microstructure of the ginkgo leaf. Specifically, the core deformation part of the sensor under the applied force has been fabricated by imprinting the array-like microscopic shapes of the ginkgo leaves. The MXene-based pressure sensor was prepared by spraying the MXene onto the polydimethylsiloxane (PDMS) model film with the ginkgo leaf structure. To further enhance the sensitivity, a layer of polyvinyl alcohol (PVA) fiber fabricated by the electrospinning method was weaved between the MXene-based element and the electrodes in the sensor. Then, the obtained pressure sensor demonstrated ultrahigh sensitivity of 403.46 kPa −1 , short response time of 99.3 ms and extraordinary durability with 12,000 loading–unloading cycles. Furthermore, the microstructure change of the sensor under applied pressure was observed through the in-situ scanning electron microscope (SEM) experiment. Meanwhile, the pressure sensor also displays great potential applications ranging from the physiological signal test to the human–computer interaction field.

Research and Realization of an OCT-Guided Robotic System for Subretinal Injections

Yunyao Li,Sujian Wu,Guohua Shi

For retinal degenerative diseases, advanced therapies such as gene therapy and retinal stem cell therapy have emerged as promising treatments, which are often delivered through subretinal injection. However, clinical subretinal injection remains challenging due to the extremely high precision requirements, lack of depth information, and the physiological limitations of manual operation, often leading to complications such as hypotony and globe atrophy. To address these challenges, this study proposes a novel ophthalmic surgical robotic system designed for high-precision subretinal injections. The robotic system incorporate a remote center of motion mechanism for its mechanical structure and employs a master–slave control system to achieve motion scaling. A microscope-integrated optical coherence tomography device is applied to provide real-time microscopic imaging and depth information. The design and performance of the proposed system are validated through simulations and experiments. Precision tests demonstrate that the system achieves an overall positioning accuracy of less than 30μm, with injection positioning accuracy under 20μm. Subretinal injection experiments conducted on artificial eye models further validate the clinical feasibility of the robotic system.

Highly efficient separation of lithium isotopes using an EMC-based electromigration system

Pengbing He,Qionghua Xie,Jinyu Wang,Guocheng Yao,Liangshi Wang

Efficient separation of lithium isotopes is crucial for nuclear energy, isotope geochemistry, and advanced energy storage. This study developed an electromigration system that uses organic solvents as the separation medium. The system investigated the effects of solvent type, lithium salt species, and migration path length. The EMC-based system demonstrated superior isotopic selectivity, achieving a separation factor exceeding the industrial benchmark of 1.050 under conditions of 16 V, 0.1 mol∙L −1 LiTFSI anolyte, a 10 cm path length, and 3 h of operation. In contrast, the DMA-based system exhibited significantly higher Li + flux due to weaker coordination, albeit with lower isotope selectivity. Molecular dynamics simulations revealed distinct solvation behaviors. EMC formed dense LiTFSI clusters that enhanced isotope selectivity but impeded ion transport, whereas DMA formed looser complexes that facilitated faster ion migration. Radial distribution functions and coordination numbers confirmed stronger Li + interactions with EMC compared to DMA. These findings establish a mechanistic understanding of the trade-off between isotopic separation efficiency and ion flux, providing both theoretical and experimental guidance for designing high-performance lithium isotope separation systems.

3D framework energetic composites: an efficient catalyst for ammonium perchlorate thermal decomposition

Teng Liu,Peirong Kuang,Wenchao Tong,Jinlong Cui,Wenyuan Zhao

A series of M 2 -L@OBC composites (M = Cu(II), Co(II), Fe(III); L = 5-Nitro-3-pyrazolecarboxylic acid; M:L molar ratio = 2:1; OBC = carboxylated bacterial cellulose) with 3D-networknet structure were successfully synthesized and utilized to improve the thermal decomposition of ammonium perchlorate (AP). The M 2 -L@OBC composites were characterized by IR, SEM, TEM, HRTEM, XPS and XRD, and the results indicate that the M 2 -L nanoparticles are evenly covered on cellulose fibers. The catalytic effects were investigated using the non-isothermal method, which shows that the Fe 2 -L@OBC composites exhibits excellent performance. The peak temperature of the high-temperature decomposition (HTD) stage of AP mixing 2 wt% Fe 2 -L@OBC advanced by 66 °C, the activation energy decreased by 56 kJ/mol, and the reaction rate constant increased by 1.1 times. Furthermore, online TG/FT-IR revealed that Fe 2 -L@OBC composites could significantly accelerate the consumption of HClO 4 and NH 3 to the conversion of N 2 O, NO, and NO 2 . This is attributed to the abundant active sites on the Fe 2 -L@OBC surface, which provide fresh active sites after decomposing into metal oxide nanoparticles, thereby promoting the electron transfer process in the HTD stage.

Rosmarinic Acid Is an hCtr1 Inhibitor that Interferes with Copper Transport Activity

Fei Chen,Sisi Wu,Jian Kuang,Sijia Xiang,Shenghu Wang,Siming Yuan,Kaiming Cao,Lu Yu,Wenming Yang,Liqin Tang,Yangzhong Liu

Human copper transporter 1 (hCtr1) is a transport protein essential for cellular copper uptake and homeostasis, yet excess copper influx is toxic to cells. Currently, no inhibitors of hCtr1 are available to modulate intracellular copper levels. Here, we discovered that the natural phenolic compound rosmarinic acid (RA), as a moderate-strength copper chelator, can directly interact with hCtr1 and inhibit its copper-transport function. RA binds to the N-terminal copper-binding domain of hCtr1, lowering the Cu(II)-binding affinity of hCtr1. More crucially, RA and hCtr1 form a ternary complex with Cu(II) ions (RA/Cu/hCtr1). Cellular assays indicated that RA inhibited the copper-mediated membrane interaction of the hCtr1 N-terminal copper-binding domain, a crucial step in triggering cellular copper internalization. Functional assays showed that RA significantly inhibits hCtr1-mediated copper uptake under high copper conditions, hence effectively alleviating cellular copper overload and attenuating copper-induced cytotoxicity. Notably, the moderate copper-binding affinity of RA minimizes adverse effects while modulating the cellular copper levels. This work identifies RA as a promising lead compound for modulating copper-related pathologies and provides a strategy for regulating intracellular copper homeostasis by targeting hCtr1.

An undescribed biflavone from coastal halophyte Suaeda maritima subsp. salsa (L.) Soó

Di Zhang,Yujiang Dai,Xin Wang,Qi Mai,Lu Jiang,Tuanjie Wang,Huifang Li,Xing Ren,Rongbin Wei

The halophyte Suaeda maritima subsp. salsa (L.) Soó has been utilised as a traditional medicinal herb in China. Its phytochemical profile remains inadequately elucidated to date. In this study, twelve compounds, including one previously undescribed biflavonoid, 3′-methoxy-4′,4′″,5,5″-tetrahydroxy-[C7-O-C7″]-biflavone (1), and eleven known compounds (2∼12), were isolated from the whole plant of S. salsa. Their structures were fully determined via NMR, MS data analysis and literature comparison. The anti-microbial assay revealed that compounds 1, 9, and 12 exhibited an inhibitory effect against P. aeruginosa with an MIC of 25 μg/mL. Additionally, compounds 3, 5, 7, 9 and 12 displayed potent inhibitory activity against the growth of E. coli, with their MIC values ranging from 12.5 to 25 μg/mL. Furthermore, compound 1 showed the cytotoxic activity against human SGC-7901 cells with an IC50 of 89.04 ± 0.26 μm. Biflavonoid 1 represents the first reported occurrence of this class of compounds within the genus Suaeda.

Material and system design: an all-weather multi-functional interface solar evaporator

Guangxu Liu,Hanyu Chang,Long Wang,Hui Deng,Yang Wang,Qiubai Jiang,Bingyu Wang,Min Zhang,Hao Guo,Zilong Liu

Interfacial solar evaporation is a promising technology for water treatment. However, its practical application is limited by variable light conditions, salt accumulation, and secondary pollution of the condensate. In this study, carbon obtained by co -pyrolysis of sludge and corn cob (SC) was combined with sodium alginate (SA) and polyvinyl alcohol (PVA) to fabricate an SC@SA@PVA gel evaporator. The evaporator was mounted on a salt-resistant evaporation substrate. Evaporation experiments were conducted under two auxiliary modes: electric heating and solar concentrator assistance. Benefiting from the adsorption and photocatalytic properties of the sludge-derived carbon, the system enabled simultaneous water evaporation and the evaporated phenol removal. A removal efficiency of 80.6 % was achieved for a 10 mg·L −1 phenol solution. Coupled with the electric heating and solar concentration devices, the evaporation rate increased from 2.28 to 4.19 kg·m −2 ·h −1 , corresponding to an 83.8 % enhancement. In addition, an evaporation rate of 1.39 kg·m −2 ·h −1 was maintained at night. Moreover, the salt-resistant evaporation substrate provided water transportation, salt resistance, and heat management. These functions ensured the long-term stable operation of the system. Through the integration of sludge resource utilization and a multifunctional system design, this study provides a new path for the development of efficient, stable, and water-purifying next-generation interfacial evaporation technologies.

An Efficient Synthesis of 1,2,3-Triazole Bridge-Connected Phosphonate Derivatives of Coumarin

Xu Li,Xiaolan Chen,Jinwei Yuan,Yang Liu,Peipei Li,Lingbo Qu,Yufen Zhao