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Chinese Journal of Chemistry 2023年第11期41卷 1348-1354页

作者： Xin-Yi Zhang kai-Li tian Jie Liu Wittaya Ngeontae Ai-Juan Zhao Maxim V. Bermeshev Shi-Qing Wong Kaspars Traskovskis Zhijian Chen Xiang-Kui Ren School of Chemical Engineering and Technology State Key Laboratory of Chemical EngineeringTianjin UniversityTianjin300350 China Department of Chemistry Faculty of ScienceKhon Kaen UniversityKhon Kaen40002 Thailand A.V.Topchiev Institute of Petrochemical Synthesis of Russian Academy of Sciences Moscow119991 Russia Faculty of Materials Science and Applied Chemistry Riga Technical UniversityRigaLV-1048 Latvia Zhejiang Institute of tianjin University NingboZhejiang315201 China

A novel polyurethane polymer containing perylene diimide(PDI)unit and aniline segment,denoted as PU-PDI,was designed and *** tensile property and photophysical characteristic were investigated using various experimental and theoretical *** is found that the elongation of PU-PDIs can reach more than 1000%,indicating good tensile ***,based on the photoinduced electron transfer mechanism,the aniline segments in polyurethane can quench the auto-fluorescence of PDI unit to a negligible value,which overcomes the intractable fluorescence drawbacks of conventional colour *** non-emissive characteristic,in combination with the good thermal stability and tensile property of PU-PDI,provides a feasible design strategy to fabricate optical filters with high display quality.

关键词： Perylene dimide Polyurethane Photoinduced electron transfer Fluorescence quenching Colour filter

In situ regulating intimately connected heterostructure by decomposition of solid solution oxides toward high-efficient water oxidation

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Rare Metals 2024年第4期43卷 1557-1569页

作者： Shao-Fei Zhang Xiao-Lu Yin Jin Wang Jian-Li Kang tian-tian Li Jin-Feng Sun Yong-Qiang Meng Jian-Jiang Wang Dian-Long Wang kai-Qiang Qin Hebei Key Laboratory of Flexible Functional Materials/Hebei Key Laboratory of Material Near-Net Forming Technology School of Materials Science and EngineeringHebei University of Science and TechnologyShijiazhuang050018China Key Laboratory of Advanced Ceramics and Machining Technology/Ministry of Education School of Materials Science and EngineeringTianjin UniversityTianjin300072China Electrochemical Engine Center Department of Mechanical EngineeringPennsylvania State UniversityUniversity ParkPA16802USA

Heterogeneous interfaces produced by interdomain interactions on a nanoscale performs a crucial role in boosting the properties of an electrocatalyst toward oxygen evolution reaction(OER)***,a series of dual-phase electrodes with intimately connected heterointerfaces are prepared by in situ decomposing solid solution oxide of Ni_(x)Co_(y)Fe_(100-x-y)O,which grew on Ni foam massively via an ultrafast combustion ***,with high-reaction kinetics caused by the reduction treatment at 450℃,the less electronegative Fe and Co are more oxyphilic than Ni,which facilitated their co-exsolution and formation of CoFe_2O_4/NiO oxide with enriched oxygen *** from the nanoporous framework,heterojunction structure,and oxygen defects,the self-supporting electrodes present rapid charge/mass transmission and provide abundant active sites for *** optimized sample(R-SNCF4.5)shows low overpotentials of 226 and 324 mV at 10 and100 mA·cm^(-2),a small Tafel slope(46.7 mV·dec^(-1)),and excellent *** assembled R-SNCF4.5//Pt/C/NF electrolyzer demonstrates continuous electrolysis over 50 h at a current density of 10 mA·cm^(-2),under 1.51 *** functional theory(DFT)calculations verify that the strong electronic modulation plays a critical part in the CoFe_2O_4/NiO hybrid by lowering the energy barriers for the ratedetermining steps,and Fe sites are the most active OER sites.

关键词： Rapid combustion Decomposition of solid solution oxide Dual-phase heterostructure Oxygen evolution reaction Theoretical calculation

Preparation of Laser Cladding Coating Undercooling Cu-based Alloy and Co on Non-equilibrium Solidification Structure

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Journal of Wuhan University of Technology(Materials Science) 2024年第2期39卷 463-472页

作者：田徐铭 CAO Shichao HOU kai HOU Xiaopeng WANG Hongfu 张煜 Department of Outpatient Xinzhou People’s HospitalXinzhou 034099China School of Mechanical Engineering North University of ChinaTaiyuan 030051China Department of Neurosurgery Xinzhou People’s HospitalXinzhou 034099China Department of Orthopedics Xinzhou People’s HospitalXinzhou 034099China

The effect of the gradient content of Co element on the solidification process of Cu-based alloy under deep under cooling conditions was *** non-equilibrium solidification structure of the under cooled alloy samples were *** is found that the rapidly solidified alloy has undergone twice grain refinement during the undercooling *** and significance of the maximum undercooling refinement structure of Cu60Ni35Co5 at T=253 K were ***-density defects were observed,such as dislocations,stacking faults networks,and twinning *** standard FCC diffraction pattern represents that it is still a single-phase *** on the metallographic diagram,EBSD and TEM data analysis,it is illustrated that the occurrence of grain refinement under high undercooling is due to stress induced *** addition,the laser cladding technology is used to coat Co-based alloy(Stellite12) coating on 304 stainless steel substrate;the microstructure of the coating cross-section was *** was found that the microstructure of the cross-section is presented as columnar crystals,planar crystals,and disordered growth direction,so that the coating has better hardness and wear *** electrochemical corrosion of the substrate and coating,it can be seen that the Co and Cr elements present in the coating are more likely to form a dense passivation film,which improved the corrosion resistance of the coating.

关键词： non-equilibrium solidification structure undercooling recrystallization laser cladding coating

Insights into in-situ imbibition behavior of fracturing fluid in propped shale fractures based on nuclear magnetic resonance:A case study from Longmaxi Formation shale,Sichuan Basin,China

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Petroleum Science 2024年第1期21卷 410-429页

作者： Jing-Jing Guo kai-Xiang Di Lie-Hui Zhang Yu-Long Zhao Hui-Ying Tang Rui-Han Zhang Ye tian National Key Laboratory of Oil and Gas Reservoir Geology and Exploitation Southwest Petroleum UniversityChengdu610500SichuanChina

Shale gas is an important component of unconventional oil and gas *** the imbibition behavior is helpful to optimize flowback parameters and enhance gas *** imbibition studies have focused on shale matrix,and the pressure conditions discussed were mostly *** initial imbibition behavior begins from propped fractures to matrix,but there are few studies working on explaining the imbibition behavior in propped fractures or the phenomenon of many shale wells exhibit higher productivity after a“soaking”***,propped fracture samples were designed for imbibition and migration *** order to accurately study the mechanism and main influencing factors of fracturing fluid imbibition and migration in propped and unpropped shale fractures under high temperature and high pressure,a series of experiments based on nuclear magnetic resonance(NMR)were carried *** showed that NMR T_(2) spectra of all samples exhibited a bimodal *** final imbibition volume of fracturing fluid was positively related to pressure and fracture *** imbibition effect of fracturing fluid was more evident in matrix pores under high *** the migration during soaking stage,the fracturing fluid gradually migrated from large pores to small pores and gradually displaced the shale gas from the matrix,thus allowing the water blocking in propped fractures to self-unlock to some *** permeability decreased in the imbibition stage,while it recovered in the migration stage to some extent.

关键词： Forced imbibition Migration Soaking NMR T_(2)spectra Propped fracture Permeability recovery

Molecular mechanism of lycopene cyclases regulating carotenoids ratio in different branches during tea leaf and flower development

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Horticultural Plant Journal 2023年第6期9卷 1177-1192页

作者： Anqi Peng Xiaoyan Tang Yingying Feng Yun Huang Jilai Cui kai tian Mengqian Lu Yifan Zhao Yuting Pan Sanjin Wang Yutong Hu Wei Zhao Chuankui Song Qiang Wang State Key Laboratory of Tea Plant Biology and Utilization and International Joint Laboratory on Tea Chemistry and Health Effects Anhui Agricultural UniversityAnhuiHefei 230036China Hefei Ecological Environment Monitoring Center AnhuiHefei 230036China College of Life Science Xinyang Normal UniversityXinyangHenan 464000China Henan Field Observation and Research Station of Headwork Wetland Ecosystem of the Central Route of South-to-North Water Diversion Project School of Life Sciences and Agricultural EngineeringNanyang Normal UniversityNanyangHenan 473061China

Carotenoids are essential components in tea quality, contributing to leaf color and aroma. However, little information about carotenoids in different tea cultivars and their biosynthesis regulation mechanism during leaf development is known. Here we analyzed carotenoids by HPLC in the buds and leaves of 113 tea cultivars harvested on the same day. By profile clustering, carotenoids were divided into five groups. Same group cultivars displayed divergence in the total content of carotenoids but a similar molar ratio. To figure out the molecular mechanisms of this phenomenon, we further characterized all functional lycopene cyclases, which are the branch point of the carotenoid biosynthesis pathway. Two β-lycopene cyclases(CsLCYB1 and CsLCYB2) and one ε-lycopene cyclase(CsLCYE1) were cloned. Subcellular localization analysis showed that all cloned CsLCYs were localized in plastids. Enzyme activity assays in E. coli indicated both CsLCYBs catalyzed lycopene into β-carotene, and CsLCYE1 produced δ-carotene and ε-carotene. We found CsLCYB1 and CsLCYE1 predominantly expressed in leaf, while CsLCYB2was mainly expressed during flowering stages. Suppression by antisense oligonucleotides reduced CsLCYB1 and CsLCYE1 transcripts and led to reduction of both β,β-branch and β,ε-branch carotenoids in leaf. The expression levels of CsLCYB1 showed a significant positive correlation withβ,β-branch carotenoids in leaf. Our study provides carotenoid profiles of different tea cultivars, which can assist tea producers in selecting cultivars of interest. Meanwhile, we proposed the molecular mechanism of carotenoids reflecting the tenderness of tea plant leaf from a metabolic flux perspective, and suggested lycopene cyclase that could be applied to the breeding of tea varieties with different branch carotenoids.

关键词： Camellia sinensis Carotenoids Lycopene cyclase Metabolicﬂux Leaf development Flower

1-D Directional Filter Based Texture Descriptor in Fractional Fourier Domain

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Journal of Harbin Institute of Technology(New Series) 2015年第5期22卷 125-128页

作者： kai tian Hongzhang Jin Liying Zheng College of Automation Harbin Engineering University College of Computer Science and Technology Harbin Engineering University

Texture analysis is a fundamental field in computer vision. However,it is also a particularly difficult problem for no universal mathematical model of real world textures. By extending a new application of the fractional Fourier transform( Fr FT) in the field of texture analysis,this paper proposes an Fr FT-based method for describing textures. Firstly,based on the Radon-Wigner transform,1-D directional Fr FT filters are designed to two types of texture features,i. e.,the coarseness and directionality. Then,the frequencies with maximum and median amplitudes of the Fr FT of the input signal are regarded as the output of the 1-D directional Fr FT filter. Finally,the mean and the standard deviation are used to compose of the feature vector. Compared to the WD-based method,three benefits can be achieved with the proposed Fr FT-based method,i. e.,less memory size,lower computational load,and less disturbed by the cross-terms. The proposed method has been tested on16 standard texture images. The experimental results show that the proposed method is superior to the popular Gabor filtering-based method.

关键词： fractional Fourier transform texture analysis Radon-Wigner transform 1-D directional window

Bioengineered skin organoids:from development to applications

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Military Medical Research 2024年第3期11卷 449-466页

作者： Zi-Xuan Hong Shun-tian Zhu Hao Li Jing-Zhi Luo Yu Yang Yang An Xi Wang kai Wang Department of Physiology and Pathophysiology School of Basic Medical SciencesState Key Laboratory of Vascular Homeostasis and RemodelingPeking UniversityBeijing 100191China Department of Hepatopancreatobiliary Surgery the Third Affiliated Hospital of Soochow UniversityChangzhou 213000JiangsuChina Department of Plastic Surgery Peking University Third HospitalBeijing 100191China Clinical Stem Cell Research Center Peking University Third HospitalBeijing 100191China State Key Laboratory of Cardiovascular Disease Fuwai HospitalBeijing 100037China Beijing Key Laboratory of Metabolic Disorder Related Cardiovascular Disease Capital Medical UniversityBeijing 100050China

Signifcant advancements have been made in recent years in the development of highly sophisticated skin *** as three-dimensional(3D)models that mimic human skin,these organoids have evolved into complex structures and are increasingly recognized as efective alternatives to traditional culture models and human skin due to their ability to overcome the limitations of two-dimensional(2D)systems and ethical *** inherent plasticity of skin organoids allows for their construction into physiological and pathological models,enabling the study of skin development and dynamic *** review provides an overview of the pivotal work in the progression from 3D layered epidermis to cyst-like skin organoids with ***,it highlights the latest advancements in organoid construction facilitated by state-of-the-art engineering techniques,such as 3D printing and microfuidic *** review also summarizes and discusses the diverse applications of skin organoids in developmental biology,disease modelling,regenerative medicine,and personalized medicine,while considering their prospects and limitations.

关键词： Skin organoid Organoid generation Skin appendage Tissue engineering Disease modelling Regenerative medicine

Improving the Catalytic Activity of Au25 Nanocluster by Peeling and Doping

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Chinese Journal of Chemistry 2017年第5期35卷 567-571页

作者： Man-bo Li Shi-kai tian Zhikun Wu Key Laboratory of Materials Physics Anhui Key Laboratory of Nanomaterials and Nanotechnology CAS Center for Excellence in Nanoscience Institute of Solid State Physics Chinese Academy of Sciences Hefei Anhui 230031 China Department of Chemistry University of Science and Technology of China Hefei Anhui 230026 China

Tuning the nanoclusters＇ compositions and structures is critical for the performance improvement of ***,a well-known Au25（SCH2CH2Ph）18 （Au25 for short） nanocluster has been transformed to a rare cadmium doped gold nanocluster [Au13Cd2（PPh3）6（SC2H4Ph）6（NO3）2]2Cd（NO3）4 （Au26Cd5 for short） by peeling and *** Au25 exhibits no catalytic activity toward A3-coupling reaction under the investigated conditions,the novel cadmium doped gold nanocluster Au26Cd5 shows high catalytic activity,as well as good recyclability and substrate tolerance for the same *** high catalytic activity is attributed to the cooperation between the exerted cadmium atoms and the neighbor gold atoms on the surface of Au13 *** work has important implication for the tuning of nanoclusters＇ compositions and structures targeting the improvement of catalytic performance by some unusual but effective strategies.

关键词： peeling doping gold nanocluster A^3-coupling reaction catalysis

A 128×128 SPAD LiDAR sensor with column-parallel 25 ps resolution TA-ADCs

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Journal of Semiconductors 2024年第8期45卷 34-40页

作者： Na tian Zhe Wang kai Ma Xu Yang Nan Qi Jian Liu Nanjian Wu Runjiang Dou Liyuan Liu State Key Laboratory of Superlattices and Microstructures Institute of SemiconductorsChinese Academy of SciencesBeijing 100049China Center of Materials Science and Optoelectronics Engineering University of Chinese Academy of SciencesBeijing 100049China

This paper presents a design of single photon avalanche diode(SPAD)light detection and ranging(LiDAR)sensor with 128×128 pixels and 128 column-parallel time-to-analog-merged-analog-to-digital converts(TA-ADCs).Unlike the conventional TAC-based SPAD LiDAR sensor,in which the TAC and ADC are separately implemented,we propose to merge the TAC and ADC by sharing their capacitors,thus avoiding the analog readout noise of TAC’s output buffer,improving the conversion rate,and reducing chip *** reverse start-stop logic is employed to reduce the power of the *** in a 180 nm CMOS process,our prototype sensor exhibits a timing resolution of 25 ps,a DNL of+0.30/−0.77 LSB,an INL of+1.41/−2.20 LSB,and a total power consumption of 190 mW.A flash LiDAR system based on this sensor demonstrates the function of 2D/3D imaging with 128×128 resolution,25 kHz inter-frame rate,and sub-centimeter ranging precision.

关键词： 3D imaging CMOS imagers direct time-of-flight(dTOF) time-to-analog converter(TAC)

Density Functional Theory Study of Water Diffusion and Clustering on Pd(111)

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Chinese Journal of Structural Chemistry 2006年第8期25卷 909-914页

作者： CHEN Jin-Wen TU Xue-Yan tian kai DAI Shu-Shan School of Chemical Science and Technology Yunnan University Kunming 650091 China School of Chemistry. and Biotechnology Yunnan Nationalities University Kunming 650031 China School of Chemistry and Chemical Engineering Hunan Universi of Science and Technology Xiangtan 411201 China

The internal structures as well as adsorption and hopping energies of monomers, dimers, trimers, tetramers, pentamers and hexamers of water on Pd（111） have been studied by density functional theory （DFT） plane-wave pseudopotential method which performs the firstprinciples quantum-mechanical calculations to explore the properties of crystals and surfaces in materials. Based on the calculations, we suppose that their absorption is via one water molecule for monomers, dimmers and trimers, but three water molecules for pentamers and hexamers. Moreover, there is one water molecule bonding with Pd atom by O atom in pentamers and hexamers, which explains why pentamers and hexamers are stable. The binding energies of polymers may be used to explain why the trimer comes close to two nearby monomers to form a stable pentamer instead of tetramer. And the difference of mobility of small water clusters is due to their different hopping energies.

关键词： density functional theory Pd(111) surface water diffusion and clustering binding energy hopping energy