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12th International Conference on Advanced Materials and Engineering Materials, ICAMEM 2023

作者： peng, Zhang Yuwei, Liu Li, Sun Tianzhen, Gu shuwen, Mei Zhenyao, Wang National Engineering Laboratory of Advanced Coating Technology for Materials China Iron & Steel Research Institute Group Beijing100081 China Institute of Metal Research Chinese Academy of Science Shenyang110016 China HBIS Group Technology Research Institute Shijiazhuang050023 China Tangshan Iron & Steel Group Co. Ltd. Tangshan063000 China

ISBN: (纸本)9789819735297

Zn–Al–Mg coating is based on zinc plating, adding a small amount of Al and Mg elements to form a complex corrosion resistance structure to achieve high corrosion resistance. However, the development of period of Zn–Al–Mg coating is short, and further research is required to determine its suitability for different environments. Thus, the corrosion behavior of Zn–Al–Mg coated steel exposed to the atmosphere for 24 months in Shenyang was studied by means of weight loss, morphology observation, composition, energy spectrum analysis, and electrochemical analysis. The results show that the corrosion rate of Zn–Al–Mg coating decreases first and then increases with the extension of time, and the average annual corrosion rate of Zn–Al–Mg coating in the second year is higher than that in the first year. The corrosion process is different between the skyward and field-ward sides. After exposure for 12 and 24 months, the corrosion rate of the skyward side was lower than that of field-ward side, and the corrosion rate difference between the two sides after exposure for 24 months was smaller than that after exposure for 12 months. The densified corrosion product Zn4(SO4)(OH)6·4H2O can effectively reduce the corrosion rate of skyward side. Corrosion pits and cracks are easy to form on the field-ward side, which accelerates the corrosion process of field-ward side, thus increasing the overall average annual corrosion rate of the sample. © The Author(s), under exclusive license to Springer Nature Singapore Pte Ltd. 2024.

关键词： Aluminum corrosion

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Quantum noise ciphered optical stealth communication based on equivalent spectral encoding

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OPTICS EXPRESS 2022年第21期30卷 38128-38138页

作者： Zhu, Huatao Liu, Zhanqi Xiang, peng Chen, shuwen LI, Feiyu Xu, Xiangming Natl Univ Def Technol Coll Informat & Commun Wuhan 430010 Peoples R China Army Engn Univ Coll Commun Engn PLA Nanjing 210007 Peoples R China

To provide secure and covert transmission for optical communication system at the same time, a quantum-noise stream ciphered optical stealth communication approach is proposed for the first time. In the proposed system, the optical pulses are time spread by a chromatic dispersion device and then phase modulated with optical codes at chip rate to realize an equivalent spectral encoding. Binary optical codes are converted to multiple level phase-shift keying signal according to Y-00 protocol. The encoded optical signals are attenuated to mesoscopic coherent states and sent to a public channel. The ciphered signals are stealthy transmitted under public channel noise. The availability and covertness of the optical stealth channel is verified by system simulations.

关键词： Coherent states Laser communications Optical code division multiple access Optical networks Quantum communications Quantum noise

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A novel off-on fluorescent probe for imaging of hypoxia in tumor cell

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JOURNAL OF PHOTOCHEMISTRY AND PHOTOBIOLOGY A-CHEMISTRY 2018年第0期353卷 292-298页

作者： Wei, Chen Shen, Yuanzhi Xu, Zhiqiang peng, shuwen Yuan, Zhenwei He, Yuanyuan Yin, Jun Chen, Haiyan China Pharmaceut Univ Sch Engn Dept Biomed Engn State Key Lab Nat Med 24 Tongjia Lane Nanjing 210009 Jiangsu Peoples R China Cent China Normal Univ Coll Chem Minist Educ Key Lab Pesticide & Chem Biol Wuhan 430079 Hubei Peoples R China

A novel off-on fluorescent probe, developed for imaging the hypoxic status of tumor cells by means of detecting nitroreductase (NTR), consisted of a naphthalimide fluorophore and 4-Nitrobenzyl chloroformate as exogenous hypoxia markers. The detection mechanism is based on the fact that nicotinamide adenine dinucleotide (NADH) is utilized by nitroreductase as an electron source to reduce nitroaromatics to corresponding amino derivatives. The fluorescence of probe displays distinct change from very weak fluorescence to strong green fluorescence at 550 nm after reaction with NTR. The fluorescence intensity increase of probe shows a good linearity when the concentration of NTR is in the range of 0.1-0.3 mu g/mL. The probe shows significant specificity with NTR and good biocompatibility. The result of laser confocal fluorescence imaging confirmed that probe can successfully differentiate normoxic (non-fluorescent) from hypoxic conditions (strong green fluorescence) in U87 cell lines. All the results demonstrate that our probe is a promising optical imaging candidate for tumor hypoxia and can be potentially used for the detection of hypoxic-ischemic diseases. (C) 2017 Elsevier B.V. All rights reserved.

关键词： Naphthalimide Fluorescent probe Nitroreductase Hypoxia

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Biocompatible tumor-targeting nanocomposites based on CuS for tumor imaging and photothermal therapy

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RSC ADVANCES 2018年第11期8卷 6013-6026页

作者： Liang, Li peng, shuwen Yuan, Zhenwei Wei, Chen He, Yuanyuan Zheng, Jinrong Gu, Yueqing Chen, Haiyan China Pharmaceut Univ Sch Engn Dept Biomed Engn 24 Tongjia Lane Nanjing 210009 Jiangsu Peoples R China

Active targeting of tumor receptors is a significant approach for cancer diagnosis. Additionally, development of photothermal agents for photothermal therapy (PTT) has attracted great interest in the field of nanomedicine. In the present study, copper sulfide (CuS) nanoparticles capped with bovine serum albumin (BSA), named CuS@BSA, was synthesized by a convenient method. Then, the near-infrared (NIR) fluorescence probe MBA and the tumor-targeting ligand cyclic RGD were further conjugated on the surface of CuS@BSA, and the obtained nanocomposite was named CuS@BSA-MBA-cRGD. The morphology, optical properties, biotoxicity, tumor-targeting capability and in vitro and in vivo tumor inhibition effect were all characterized comprehensively. This nanocomplex demonstrated enhanced photothermal effects and positive tumor targeting. Thus, the nanocomposite CuS@BSA-MBA-cRGD can used as a promising tumor-targeting PTT agent for simultaneous cancer imaging and photothermal treatment.

关键词： Copper compounds

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Molecular-level transformations of biomass burning-derived water-soluble organic carbon during dark aqueous OH oxidation: Insights from absorption, fluorescence, high-performance size exclusion chromatography and high-resolution mass spectrometry analysis

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SCIENCE OF THE TOTAL ENVIRONMENT 2024年 912卷 169290页

作者： Fan, Xingjun Xie, shuwen Yu, Xufang Cheng, Ao Chen, Dan Ji, Wenchao Liu, Xiaolong Song, Jianzhong peng, Pingan Anhui Sci & Technol Univ Coll Resource & Environm Fengyang 233100 Peoples R China Chinese Acad Sci State Key Lab Organ Geochem Guangzhou Inst Geochem Guangzhou 510640 Peoples R China Univ Chinese Acad Sci Beijing 100049 Peoples R China

Biomass burning (BB) releases large amounts of water-soluble organic carbon (WSOC), which would undergo heterogenous oxidation processes that induce transformations in both molecular structures and compositions within BB WSOC. This study designed an aqueous oxidation initiated by OH radicals in the absence of light for WSOC extracted from smoke particles generated by burning of corn straw and fir wood. The BB WSOC was comprehensively characterized using a combination of UV-visible spectra, excitation-emission matrix fluorescence in conjunction with parallel factor analysis (EEM-PARAFAC), high-performance size exclusion chroma-tography (HPSEC), and high-resolution mass spectrometry (HRMS) analyses. Over the course of oxidation, both chromophores and fluorophores exhibited gradual decreases. Moreover, EEM-PARAFAC revealed a preferential degradation of larger-sized protein-like/phenol-like organic matters, accompanied by the accumulation and/or formation of humic-like substances in aged BB WSOC. HPSEC analysis showed notable changes in molecular weight (MW) distributions for both types of BB WSOC during oxidation. Specifically, high MW species (>1 kDa) displayed a tendency to form along with oxidation, possibly attributed to the formation of assemblies via intermolecular weak forces. After oxidation, evidence of CHO compound degradation and enrichment/formation of CHON compounds was observed for both types of BB WSOC. Remarkably, the resistant, degraded and produced molecules for BB WSOC were dominated by CHO (38-73 %) and lignin-like molecules (41-47 %), suggesting diverse responses to oxidation within these two groups. Furthermore, polyphenols experienced selective degradation, while CHON, aliphatic and poly-aromatic molecules tended to form during the oxidation process for both types of BB WSOC. In summary, this study provides a comprehensive understanding of the molecular-level transformations undergone by BB WSOC during dark aqueous OH oxidation. The findings sign

关键词： Water-soluble organic carbon Biomass burning Dark aqueous OH oxidation Optical properties

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Expediting hole transfer via surface states in hematite-based composite photoanodes

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NANOSCALE 2022年第45期14卷 17044-17052页

作者： Gao, Lili Wang, peng Chai, Huan Li, shuwen Jin, Jun Ma, Jiantai Lanzhou Univ Coll Chem & Chem Engn State Key Lab Appl Organ Chem SKLAOC Key Lab Catalyt Engn Gansu ProvKey Lab Adv Cataly Lanzhou 730000 Peoples R China Tianshui Normal Univ Sch Chem Engn & Technol Tianshui 741001 Gansu Peoples R China

Regarding the indirect hole transfer route in hematite-based photoelectrodes, the widely accepted viewpoint is that the Fe-IV - O states act as a hole transfer medium, while other types of surface states act as recombination centers. Alternatively, it has rarely been reported that the recombining surface states may contribute to the charge transport in modified photoelectrodes. In this study, we employed CoCr layered double hydroxide (LDH)/Fe2O3 and CoCr LDH/Zr:Fe2O3 as research models to investigate the distinct charge transfer pathways in composite photoanodes. Different from the adverse role of surface states at & SIM;0.7 V versus the reversible hydrogen electrode (r-SS) in the bare hematite photoelectrodes (Fe2O3 or Zr:Fe2O3), the r-SS in the composite photoanodes (CoCr LDH/Fe2O3 or CoCr LDH/Zr:Fe2O3) served as a hole transfer station to induce high-valent Co cations, and the position of r-SS determined the onset potential of the composite photoelectrodes. Moreover, the (FeO)-O-IV states still acted as active intermediates to transport numerous holes to the cocatalyst, which enhanced the charge utilization efficiency at 1.23 V versus the reversible hydrogen electrode (RHE) to a large extent. Besides, a noteworthy fact is that Zr doping increased the number of active (FeO)-O-IV states, which significantly contributed to the enhancement in current density. However, it led to a delayed onset potential because of the positively shifted surface states (r-SS and (FeO)-O-IV). Evidently, the different surface state distributions between Fe2O3 and Zr:Fe2O3 gave rise to anisotropic charge transfer and recombination behavior in the composite photoanodes. This study gives extensive insight into the hole transfer route in composite photoanodes and reveals the surface state-tuning effects of dopants and cocatalysts, which are significant for a deep understanding of the surface states and optimal design of composite photoanodes via surface state modulation.

关键词： Charge transfer

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Numerical Study on Flow Distribution Characteristics of Parallel Square Flow Channels Under Blockage 23rd

Numerical Study on Flow Distribution Characteristics of Para...

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23rd Pacific Basin Nuclear Conference, PBNC 2022

作者： Li, Daheng Xu, Xinyan Yu, shuwen Xiao, Jun peng, Changhong School of Nuclear Science and Technology University of Science and Technology of China Hefei China of the People’s Republic of China Beijing China

ISBN: (纸本)9789811988981

In this study, ANSYS FLUENT and RELAP5/MOD3.4 were used to calculate the influence of inlet header size and different blockage objects’ locations on the flow distribution of parallel flow channels and the wall temperature and flow field distribution were compared. The results showed that the inlet header size considerably affected the flow distribution, the blocking position slightly affected the β value, the blocking material’s influence was only local, and it has almost no effect on the non-blocked flow channel and the flow field distribution in the inlet header. The rising trend of the maximum wall temperature calculated using the two methods was the same;however, the temperature calculated using RELAP5 was greater than that calculated using FLUENT. © 2023, The Author(s), under exclusive license to Springer Nature Singapore Pte Ltd.

关键词： Parallel flow

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Lattice Oxygen-Driven Co-Adsorption of Carbon Dioxide and Nitrate on Copper: A Pathway to Efficient Urea Electrosynthesis

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JOURNAL OF THE AMERICAN CHEMICAL SOCIETY 2025年第7期147卷 6049-6057页

作者： Wei, Xiaoxiao Liu, Shao-Qing Liu, Hengjie Ding, Yutian Lei, peng-Xia Wu, shuwen Song, Li Fu, Xian-Zhu Luo, Jing-Li Shenzhen Univ Coll Mat Sci & Engn Guangdong Prov Key Lab New Energy Mat Serv Safety Shenzhen Key Lab Energy Electrocatalyt Mat Shenzhen 518060 Peoples R China Univ Sci & Technol China Natl Synchrotron Radiat Lab Hefei 230052 Anhui Peoples R China Univ Toronto Dept Mat Sci & Engn Toronto ON M5S 3E4 Canada

The electrochemical coupling of CO2 and NO3 - on copper-based catalysts presents a sustainable strategy for urea production while simultaneously addressing wastewater denitrification. However, the inefficient random adsorption of CO2 and NO3 - on the copper surface limits the interaction of the key carbon and nitrogen intermediates, thereby impeding efficient C-N coupling. In this study, we demonstrate that the residual lattice oxygen in oxide-derived copper nanosheets (OL-Cu) can effectively tune the electron distribution, thus activating neighboring copper atoms and generating electron-deficient copper (Cu delta+) sites. These Cu delta+ sites enhance CO2 adsorption and stabilize *CO intermediates, which enables the directional NO3 - adsorption at adjacent Cu delta+ sites. This mechanism shortens the C-N coupling pathway and achieves a urea yield of up to 298.67 mmol h-1 g-1 at -0.7 V versus RHE, with an average Faradaic efficiency of 31.71% at a high current density of similar to 95 mA cm-2. In situ spectroscopic measurements confirmed the formation of Cu delta+ sites and tracked the evolution of the key intermediates (i.e., *CO, *NO, *OCNO, and *NOCONO) during urea synthesis. Density functional theory calculations revealed that Cu delta+ sites promote adjacent coadsorption of *CO and *NO3, as well as *OCNO and *NO3, significantly improving C-N coupling kinetics. This study underscores the critical role of lattice oxygen in facilitating adjacent coadsorption and improving C-N coupling selectivity.

关键词： Urea

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Long-term stable and catalytic 2D MXene nanosheets wrapped with dialdehyde xylan for ultrafast gelation

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GREEN CHEMISTRY 2023年第11期25卷 4309-4318页

作者： Li, Nan Shao, Lupeng Xia, Qiang Tan, Shujun Zhao, shuwen Li, Xupeng Su, Zhenhua Hao, Xiang peng, Feng Beijing Forestry Univ MOE Engn Res Ctr Forestry Biomass Mat & Energy Beijing Key Lab Lignocellulos Chem Beijing 100083 Peoples R China Qilu Univ Technol Shandong Acad Sci Key Lab Pulp & Paper Sci & Technol Minist Educ Jinan 250353 Peoples R China China Natl Pulp & Paper Res Inst Beijing 100102 Peoples R China

Developing aqueous stable and catalytic Ti3C2Tx MXene suspensions remains a grand challenge. MXene nanosheets always undergo rapid degradation when exposed to water and oxygen, and the incorporation of reducing or capping agents may deteriorate the intrinsic characteristics of MXenes. Here, we coupled dialdehyde xylan (DAX) with MXene nanosheets to significantly increase the long-term storage of MXene in an aqueous solution (>3 months) with a dramatic enhancement of their room temperature catalytic activity for ultrafast gelation. DAX can form thick and smooth layers on the nanosheets via multiple hydrogen bonds, providing a reduction environment to prevent the occurrence of oxidation. Meanwhile, DAX can accelerate the generation of free radicals from the potassium persulfate (KPS)/MXene pair, reducing the polymerization time of vinyl monomers from similar to 30 min to similar to 90 s. Moreover, the DAX layer is capable of serving as additional crosslinks by leveraging Schiff base bonds with chitosan (CS), with the elongation at break increasing from 100% to 909%. The resultant MXene-based hydrogel can be further explored as a sustainable sensor for real-time physical signal monitoring. This work offers an enticing prospect for the development of eco-friendly and high-performance MXene-based materials.

关键词： Nanosheets

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Repurposing Xylan Biowastes for Sustainable Household Detergents

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ACS SUSTAINABLE CHEMISTRY & ENGINEERING 2023年第7期11卷 2949-2958页

作者： Wang, Hairong Li, Xupeng Zhao, shuwen Liu, Qiaoling Li, Nan Su, Zhenhua Ren, Junli Hao, Xiang peng, Feng China Natl Pulp & Paper Res Inst Beijing 100102 Peoples R China South China Univ Technol State Key Lab Pulp & Paper Engn Guangzhou 510640 Peoples R China Beijing Forestry Univ MOE Engn Res Ctr Forestry Biomass Mat & Energy Beijing Key Lab Lignocellulos Chem Beijing 100083 Peoples R China

Seeking sustainable and biocompatible detergent remains a big challenge. In this work, we report a new type of polysaccharide nanocrystal that is extracted from available industrial xylan biowastes via mild ammonium persulfate (APS) aqueous oxidation, which subsequently serves as a sustainable household detergent. By carefully adjusting the oxidation conditions (similar to 0.5 M, 60 degrees C), plate xylan hydrated nanocrystals (XNCs) can be accessed in reasonable yield (similar to 23%) with diameters of 30-50 nm and thicknesses of 5-12 nm. In comparison to the cellulose nanocrystal (CNC), the crystalline structure of XNCs demonstrates remarkable humidity-dependent behavior. Additionally, the acetylated xylan nanocrystals (AXNCs) exhibit high surface/interface activity to form stable Pickering emulsions, intriguing cleaning efficiency in removing stains from fabric surfaces, and the capability to de-wet oil from various types of tableware material. Seed germination, crop growth, and aquatic ecotoxicological evaluation demonstrate that AXNCs show no toxicity toward plants and zebrafish (median lethal concentration > 20,000 mg/L) with which they can be applied either as eco-friendly laundry or kitchen detergents. Our work presents a new avenue for converting industrial biowastes into sustainable household materials.

关键词： industrial xylan biowastes acetylated xylan nanocrystals (AXNCs) household detergents no toxicity sustainable

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