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EPOXY-BASED AZO POLYMERS WITH HIGH CHROMOPHORE DENSITY:SYNTHESIS,CHARACTERIZATION AND PHOTOINDUCED BIREFRINGENCE

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Chinese Journal of Polymer Science 2012年第3期30卷 415-422页

作者：王晓工 department of Chemical Engineering Laboratory for Advanced MaterialsTsinghua University

Three epoxy-based azo polymers （PEP-AZ-C1, PEP-AZ-CN and PEP-AZ-NT） with high chromophore density were synthesized by using post-polymerization azo-coupling reactions between epoxy-based precursor polymer （PEP-AN） and diazonium salts of 4-chloroaniline, 4-aminobenzonitrile and 4-nitroaniline, respectively. The structures and properties of the azo polymers were characterized by using 1H-NMR, FT-IR, UV-Vis and thermal analyses. The photoinduced birefringence of the azo polymers was studied by irradiating spin-coated films of the polymers with laser beam at three different wavelengths （488, 532, and 589 nm）. The results indicate that the photoinduced birefringence of the azo polymers is related with the electron-withdrawing group on azo chromophores and the excitation wavelength. The excitation wavelength that can cause the efficient responses is determined by the absorption band positions of the a~：o chromophores, which are mainly affected by the electron-withdrawing group on the chromophores. Therefore, the,. azo polymers containing chromophores with different electron-withdrawing groups show different respon,;ive behavior to the irradiation light at different wavelengths. When irradiated with 488 nm light, PEP-AZ-Cl shows the shortest time to reach the saturated birefringence but with the lowest saturation birefringence level compared with the other two azo polymers. When irradiated with 532 nm light, PEP-AZ-CN shows the shortest time to reach the saturated birefringence. When irradiated with 532 and 589 nm light, PEP-AZ-NT shows the highest saturation birefringence level.

关键词： Epoxy-based Azo polymers High chromophore density Photoinduced birefringence.

Biological and mechanical investigation of novel flax/silk protein-based nanofibrous scaffold for bone regeneration

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Progress in Natural Science:Materials International 2022年第4期32卷 443-455页

作者： M.Rama U.Vijayalakshmi department of Chemistry School of Advanced Sciences Vellore Institute of Technology

The process of bone tissue regeneration involves an intricate network of a biological macromolecules that includes proteins and peptides to support stimulation and healing response. Here, we have fabricated a novel flaxseed/silk fibroin based(dual protein) composite nanofibers using β-TCP to improve the biological properties and promote cartilage tissue regeneration along with a controllable rate of biodegradation. The physiochemical properties of PVA/β-TCP/FP:SF were characterized by FTIR, XRD, SEM, porosity, contact angle measurements and mechanical evaluation etc. This study demonstrates the biological performance of the developed nanofibers by using hemocompatibility, biodegradation ability, and apatite deposition in stimulated body fluid. Moreover, the cell viability assay was performed on MG-63 osteoblast cells and long-term antibacterial rate against E. coli and S. aureus was analysed. Docking results of flax protein and silk fibroin protein further confirmed the stable modes of intramolecular bonding and the most stable electrostatic values using theoretical calculations. Taken together,the experimental results proved that the dual protein-based fibrous scaffold was found to be up-regulated in terms of biological activity with enhanced cell adhesion and proliferation.

关键词： Flax protein Silk fibroin β-TCP Electrospinning Docking Bone regeneration

醋酸对氧化铟纳米晶形貌的影响及相关等离激元性质研究（英文）

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Science China Materials 2025年

作者：苏江彤李培显刘喆刘子沣侯小琪段俊丽戴宁李洋 School of Physics and Optoelectronic Engineering Hangzhou Institute for Advanced Study University of Chinese Academy of Sciences University of Chinese Academy of Sciences Shanghai Institute of Technical Physics Chinese Academy of Sciences School of Chemistry and Material Science Hangzhou Institute for Advanced Study University of Chinese Academy of Sciences

金属氧化物纳米晶体具有独特的尺寸及形貌依赖的光学/光电特性,因此实现金属氧化物纳米晶的可控合成对其光电应用具有重要意义.然而,目前对于金属氧化物纳米晶尺寸和形貌的关键影响因素研究相对较少.在本工作中,我们发现,在前驱体反应...

金属氧化物纳米晶体具有独特的尺寸及形貌依赖的光学/光电特性,因此实现金属氧化物纳米晶的可控合成对其光电应用具有重要意义.然而,目前对于金属氧化物纳米晶尺寸和形貌的关键影响因素研究相对较少.在本工作中,我们发现,在前驱体反应过程形成的副产物—醋酸,通过影响纳米晶的成核过程,对氧化铟纳米晶的形貌控制起了决定性作用.具体地,醋酸过量时会诱导纳米晶各向异性生长,生成纳米花;而在少量或者无醋酸条件下,所得氧化铟纳米晶呈球形.进一步地,我们探究了氧化铟纳米晶的几何形状对表面等离基元性质的影响.通过调节几何形状,可以得到在近红外到中波红外具有可调谐的表面等离基元共振吸收的等离子体纳米晶,同时展现出优异的稳定性.本工作深入探究了金属氧化物纳米晶的几何形状影响机制,为基于等离子体金属氧化物纳米晶的光电和光热应用提供更多指导.

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CO2在p族催化剂Ga2O3上的吸附与活化（英文）

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Science China Materials 2025年

作者：刘之壮匡晓旭李宝文孙成华涂溶章嵩 Chaozhou Branch of Chemistry and Chemical Engineering Guangdong Laboratory School of Materials Science and Engineering Wuhan University of Technology department of Chemistry and Biotechnology Swinburne University of Technology State Key Laboratory of advanced Technology for Materials Synthesis and Processing Wuhan University of Technology

处于极端环境下的中高温工业废气中CO2的固定和转化是一项兼具重要科学意义和挑战性的任务.Ga2O3是一种稳定的p-族化合物在热催化高温CO2废气中表现出惊人的活性,但我们其仍不清楚其反应机理.在本工作中,我们用密度泛函理论研究了11种不...

处于极端环境下的中高温工业废气中CO2的固定和转化是一项兼具重要科学意义和挑战性的任务.Ga2O3是一种稳定的p-族化合物在热催化高温CO2废气中表现出惊人的活性,但我们其仍不清楚其反应机理.在本工作中,我们用密度泛函理论研究了11种不同Ga2O3表面的CO2的吸附和活化过程.电荷转移和化学键分析表明,在基底表面Ga阳离子和O阴离子之间强大的协同效应驱动下,同时出现了电子增加和电子减少两种不同的CO2活化机制.与单一活性位点相比,这种Ga-O协同作用提高了CO2的活化效率,其中CO2δ+阳离子比CO2δ–阴离子更容易捕获H原子.据我们所知,这种双重活化机制以前从未被报道过,尤其是对于p族催化剂.我们的发现为中高温CO2废气排放的直接催化转化提供了新的见解,并为处理CO2尾气的工业级催化剂的设计提供了合理的策略.

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Advances and applications in single-cell and spatial genomics

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Science China Life Sciences 2025年

作者： Jingjing Wang Fang Ye Haoxi Chai Yujia Jiang Teng Wang Xia Ran Qimin Xia Ziye Xu Yuting Fu Guodong Zhang Hanyu Wu Guoji Guo Hongshan Guo Yijun Ruan Yongcheng Wang Dong Xing Xun Xu Zemin Zhang Beijing advanced Innovation Center for Genomics (ICG) Peking University Guangdong Provincial Key Laboratory of Genome Read and Write BGI Research Bone Marrow Transplantation Center of the First Affiliated Hospital & Liangzhu Laboratory Zhejiang University School of Medicine Life Sciences Institute and The Second Affiliated Hospital Zhejiang University BGI Research Biomedical Pioneering Innovation Center (BIOPIC) and School of Life Sciences Peking University Academy for advanced Interdisciplinary Studies Peking University Institute of Hematology Zhejiang University department of Laboratory Medicine of The First Affiliated Hospital & Liangzhu Laboratory Zhejiang University School of Medicine Center for Stem Cell and Regenerative Medicine Zhejiang University School of Medicine Zhejiang Provincial Key Lab for Tissue Engineering and Regenerative Medicine Dr.Li Dak Sum & Yip Yio Chin Center for Stem Cell and Regenerative Medicine

The applications of single-cell and spatial technologies in recent times have revolutionized the present understanding of cellular states and the cellular heterogeneity inherent in complex biological systems. These advancements offer unprecedented resolution in the examination of the functional genomics of individual cells and their spatial context within tissues. In this review, we have comprehensively discussed the historical development and recent progress in the field of single-cell and spatial genomics. We have reviewed the breakthroughs in single-cell multi-omics technologies, spatial genomics methods, and the computational strategies employed toward the analyses of singlecell atlas data. Furthermore, we have highlighted the advances made in constructing cellular atlases and their clinical applications,particularly in the context of disease. Finally, we have discussed the emerging trends, challenges, and opportunities in this rapidly evolving field.

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Enhancing Solar Photovoltaic Efficiency:A Computational Fluid Dynamics Analysis

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Energy Engineering 2025年第1期122卷 153-166页

作者： Rahool Rai Fareed HussainMangi Kashif Ahmed Sudhakar Kumaramsay Faculty of Mechanical and Automotive Engineering Universiti Malaysia Pahang Al-Sultan AbdullahPekan26600PahangMalaysia Faculty of Engineering Science&Technology Hamdard UniversityKarachi74600Pakistan Electrical Engineering department SUKKUR IBA UniversitySukkur65200Pakistan Berlin School of Business and Innovation BSBI Faculty of Computer Science and InformaticsBerlin12043Germany Automotive Engineering Centre University Malaysia Pahang Al Sultan AbdullahPekan26600PahangMalaysia Centre for Research in advanced Fluid&Processes(Fluid Centre) Universiti Malaysia Pahang Al-Sultan Abdullah(UMPSA)Paya BesarKuantan26300PahangMalaysia

The growing need for sustainable energy solutions,driven by rising energy shortages,environmental concerns,and the depletion of conventional energy sources,has led to a significant focus on renewable *** energy,among the various renewable sources,is particularly appealing due to its abundant ***,the efficiency of commercial solar photovoltaic(PV)modules is hindered by several factors,notably their conversion efficiency,which averages around 19%.This efficiency can further decline to 10%–16%due to temperature increases during peak sunlight *** study investigates the cooling of PV modules by applying water to their front surface through Computational fluid dynamics(CFD).The study aimed to determine the optimal conditions for cooling the PV module by analyzing the interplay between water film thickness,Reynolds number,and their effects on temperature reduction and heat *** CFD analysis revealed that the most effective cooling condition occurred with a 5 mm thick water film and a Reynolds number of *** specific parameters were found to maximize the heat transfer and temperature reduction *** finding is crucial for the development of practical and efficient cooling systems for PV modules,potentially leading to improved performance and longevity of solar *** cooling fluids or advanced cooling techniques that might offer even better efficiency or practical benefits.

关键词： PV module efficiency water film thickness reynolds number CFD analysis PV/T renewable energy

Effects of thin MnAl buffer layer on structural and magnetic properties of MnAl films

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Chinese Physics B 2010年第10期19卷 550-553页

作者：张旭辉马斌张宗芝金庆原 Key Lab of advanced Photonic Materials and Devices Laboratory of Advanced Materials and Department of Optical Science and Engineering Fudan University

Thin Mn（2 nm）/Al（2 nm） bilayers serving as buffer layers have been prepared prior to the deposition of MnAl films. The ferromagnetic T-phase forms in the buffer layers at an optimum substrate temperature. As a template it induces the growth of following MnAl film. Compared with the case of film without buffer layer, the growth of nonferromagnetic phase is suppressed and the structural and magnetic properties of MnAl film are improved. Weak dipolar inter-grain coupling is revealed in the MnAl film, and the magnetic reversal process is dominated by magnetic moment rotation.

关键词： Ll0 τ--MnAl buffer layer

The mechanical and water absorption properties of carbon fiber buoyancy materials under hydrostatic pressure

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Science China Technological Sciences 2025年第1期 251-265页

作者： Fanglin CONG Zihan LI Guocai YU Yang JIN Zixu ZHU Linzhi WU College of Aerospace and Civil Engineering Harbin Engineering University Key Laboratory of advanced Ship Materials and Mechanics Harbin Engineering University department of Basic Courses Naval University of Engineering

Buoyancy material technology is of paramount importance for the development of marine engineering. In this study,a novel carbon fiber buoyancy material(CFBM) is designed and prepared by utilizing composite circular tubes with light weight and high strength. To reveal the failure mechanism under hydrostatic pressure, a finite element model(FEM) based on the three-dimensional Hashin and Yeh failure criterion is developed and validated experimentally. Both the simulated and experimental results indicate that the hydrostatic strength of the CFBM is mainly determined by the buckling of carbon fiber tubes located at the edges of the CFBM. Parametric analysis is conducted to investigate the effect of the number of unit-cells,length, and wall thickness of carbon fiber tubes on the mechanical properties of the CFBM. In addition, a 60-day water absorption test of the CFBM at 12.5 MPa is conducted to characterize its durability. Experimental results indicate that the maximum water absorption rate of the CFBM is 0.59% and the hydrostatic strength is reduced by only 7.97% during the 60-day test period. Finally, the designed CFBM is used at the water depth of 1000 m as buoyancy material. Compared with traditional buoyancy materials, the proposed CFBM has significant advantages in both hydrostatic strength and density. This work has broad engineering application prospects and is of high significance for promoting the implementation of carbon fiber composites in the ocean engineering field.

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Chemical composition and anti-inflammatory activity of Boswellia ovalifoliolata essential oils from leaf and bark

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Journal of Forestry Research 2018年第2期29卷 370-378页

作者： Venkatesan Geetha Sarada Nallani Chakravarthula department of Chemistry School of Advanced SciencesVIT University

We isolated the essential oils from Boswellia ovalifoliolata *** and *** using hydrodistillation,identified the obtained compounds using gas chromatography–mass spectrometry(GC–MS) and Fourier transform-infrared spectroscopy(FT-IR),and studied the photophysical and electrochemical properties using UV–visible and fluorescence spectroscopy and cyclic *** the basis of GC–MS spectra,38 compounds were identified in the essential oil from leaves and 26 in the oil from *** bark oil contained 13.44% b-Farnesene(sesquiterpene),10.45% caryophyllene oxide(sesquiterpene) and 6.6% spathulenol,(2 Z,6 E)-(sesquiterpene alcohol); the leaf oil contained 11.1% spathulenol(sesquiterpene alcohol),9.0% caryophyllene oxide(sesquiterpenoids) and 6.3% decyl acetate(ester).FT-IR spectra confirmed the presence of aliphatic aldehydes and ketones,carboxylic acid,alcohols,esters and ethers in both oil ***–visible absorption spectra showed maximum absorbance at 245,290 and 402 nm for bark oil,and 250,285 and 325 nm for *** oil showed strong emission with maximum emission wavelength at 456 nm was higher than that of leaf oil at 414 *** essential oil had significant anti-inflammatory activity,and the reduction potential of the leaf oil was-0.44 and-0.56 e V for bark.

关键词： Essential oil Boswellia ovalifoliolata Gas chromatography–mass spectrometry Fourier transforminfrared spectroscopy Cyclic voltammetry fluorescence spectroscopy