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Chinese Journal of Aeronautics 2022年第4期35卷 55-65页

作者： Jisong ZHAO jinming zhang Boqiao WANG College of Astronautics Nanjing University of Aeronautics and AstronauticsNanjing 210016China Faculty of Rocket and Space Technology Kharkiv Aviation InstituteNational Aerospace UniversityKharkiv 61070Ukraine

A learning-based approach for solving wall shear stresses from Shear-Sensitive Liquid Crystal Coating(SSLCC) color images is presented in this paper. The approach is able to learn and establish the mapping relationship between the SSLCC color-change responses in different observation directions and the shear stress vectors, and then uses the mapping relationship to solve wall shear stress vectors from SSLCC color images. Experimental results show that the proposed approach can solve wall shear stress vectors using two or more SSLCC images, and even using only one image for symmetrical flow field. The accuracy of the approach using four or more observations is found to be comparable to that of the traditional multi-view Gauss curve fitting approach;the accuracy is slightly reduced when using two or fewer observations. The computational efficiency is significantly improved when compared with the traditional Gauss curve fitting approach, and the wall shear stress vectors can be solved in nearly real time. The learning-based approach has no strict requirements on illumination direction and observation directions and is therefore more flexible to use in practical wind tunnel measurement when compared with traditional liquid crystal-based methods.

关键词： Shear stress Measurement Shear-sensitive liquid crystal Learning-based approach Calibration

Green's functions of two-dimensional piezoelectric quasicrystal in half-space and bimaterials

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Applied Mathematics and Mechanics(English Edition) 2023年第2期44卷 237-254页

作者： Xiaoyu FU Xiang MU jinming zhang Liangliang zhang Yang GAO College of Science China Agricultural UniversityBeijing 100083China College of Engineering China Agricultural UniversityBeijing 100083China

In this paper,we obtain Green’s functions of two-dimensional(2D)piezoelectric quasicrystal(PQC)in half-space and *** on the elastic theory of QCs,the Stroh formalism is used to derive the general solutions of displacements and ***,we obtain the analytical solutions of half-space and bimaterial Green’s ***,the interfacial Green’s function for bimaterials is also obtained in the analytical *** numerical studies,a comparative study is carried out to validate the present *** numerical examples are performed to investigate the effects of multi-physics loadings such as the line force,the line dislocation,the line charge,and the phason line *** a result,the coupling effect among the phonon field,the phason field,and the electric field is prominent,and the butterfly-shaped contours are characteristic in 2D *** addition,the changes of material parameters cause variations in physical quantities to a certain degree.

关键词： Green’s function two-dimensional(2D)piezoelectric quasicrystal(PQC) Stroh formalism half-space bimaterial

Static response of functionally graded multilayered two-dimensional quasicrystal plates with mixed boundary conditions

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Applied Mathematics and Mechanics(English Edition) 2021年第11期42卷 1599-1618页

作者： Xin FENG Liangliang zhang Yuxuan WANG jinming zhang Han zhang Yang GAO College of Engineering China Agricultural UniversityBeijing 100083China College of Science China Agricultural UniversityBeijing 100083China China State Key Laboratory of Acoustics Institute of AcousticsChinese Academy of SciencesBeijing 100190China

The unusual properties of quasicrystals(QCs)have attracted tremendous attention from *** this paper,a semi-analytical solution is presented for the static response of a functionally graded(FG)multilayered two-dimensional(2 D)decagonal QC rectangular plate with mixed boundary *** on the elastic theory of FG 2 D QCs,the state-space method is used to derive the state equations composed of partial differential along the thickness ***,the Fourier series expansion and the differential quadrature technique are utilized to simulate the simply supported boundary conditions and the mixed boundary conditions,***,the propagator matrix which connects the field variables at the upper interface to those at the lower interface of any homogeneous layer can be derived based on the state *** with the interface continuity condition,the static response can be obtained by imposing the sinusoidal load on the top surfaces of ***,the numerical examples are presented to verify the effectiveness of this method,and the results are very useful for the design and understanding of the characterization of FG QC materials in their applications to multilayered systems.

关键词： two-dimensional(2D)quasicrystal(QC)laminate functionally graded material(FGM) mixed boundary condition static response differential quadrature technique

Fundamental solutions of critical wedge angles for one-dimensional piezoelectric quasicrystal wedge

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Applied Mathematics and Mechanics(English Edition) 2022年第5期43卷 709-728页

作者： Xiang MU Xiaoyu FU Liangliang zhang Zhaowei ZHU jinming zhang Yang GAO College of Science China Agricultural UniversityBeijing 100083China College of Engineering China Agricultural UniversityBeijing 100083China

Two problems of a one-dimensional(1D)piezoelectric quasicrystal(QC)wedge are investigated,i.e.,the two sides of the wedge subject to uniform tractions and the wedge apex subject to the concentrated *** virtue of the Stroh formalism and Barnett-Lothe matrices,the analytical expressions of the displacements and stresses are derived,and the generalized solutions for the critical wedge angles are *** examples are given to present the mechanical behaviors of the wedge in each *** results indicate that the effects of the uniform tractions and the concentrated force on the phonon field displacement are larger than those on the phason field.

关键词： quasicrystal(QC) wedge piezoelectric effect critical angle analytical solution

Michael addition reactions of cyclanones with acrylamides:Producing 2-carbamoylethyl derivatives or ene-lactams

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Science China Chemistry 2008年第11期51卷 1044-1050页

作者： DAI WeiFeng WANG ChaoHua zhang Xi zhang jinming LANG MeiDong Key Laboratory for Ultrafine Materials of Ministry of Education School of Materials Science and EngineeringEast China University of Science and TechnologyShanghai 200237China

The electron-withdrawing groups (EWGs) in the electrophilic alkenes employed in the Michael addition reaction are almost only CO2R, CN, COR, NO2, and SO2Ph. Although amides (CONR1R2) are also typical electron-withdrawing groups and are of great importance in organic synthesis, they are scarcely em-ployed as the EWGs of the electrophilic alkenes in the Michael addition reaction. In this work, the Mi-chael reactions of acrylamide and its derivatives with cyclanones were successfully carried out in the presence of enough radical inhibitors. The amide groups play a key role in producing the preferred products. The N-substituted acrylamides, including N-monosubstituted and N,N-disubstituted acryla-mides could react with cyclohexanone (CHn) to give the expected 2-carbamoylethyl derivatives; how-ever, acrylamide reacting with cyclohexanone only produced ene-lactam. Cyclanones also have effects on the products, while the ring size of cyclanones influences the reaction yield and the α-substituent decides the ratio of resulting isomeric ene-lactams.

关键词： Michael addition reaction cyclanone acrylamide ene-lactam 2-carbamoylethyl derivative

Spontaneous,scalable,and self-similar superhydrophobic coatings for all-weather deicing

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Nano Research 2023年第5期16卷 7171-7179页

作者： Yaohui Cheng Yirong Wang Xin zhang jinming zhang Zhiyuan He Jianjun Wang Jun zhang CAS Key Laboratory of Engineering Plastics CAS Research/Education Center for Excellence in Molecular SciencesInstitute of ChemistryChinese Academy of SciencesBeijing 100190China University of Chinese Academy of Sciences Beijing 100049China Beijing Institute of Technology Beijing 100081China

Herein,we proposed and demonstrated a facile and scalable strategy to fabricate multifunctional self-similar superhydrophobic ***,a hydrophobic cationic cellulose derivative containing imidazolium cation was synthesized by a controllable *** could effectively disperse one-dimensional(1D)multi-walled carbon nanotubes(MWCNT),because the imidazolium cations formed cation–πinteractions with ***,the synergy effect of the cationic cellulose derivative and MWCNT dispersed two-dimensional(2D)reduced graphene oxide(rGO)to obtain a three-components ***,via a simple spaying process,a superhydrophobic coating with self-similar micro-nano structures spontaneously formed from inside to outside,owing to the various nanostructures with different shapes and sizes in the dispersion and the adhesive effect of the cellulose *** superhydrophobic coating was easy to scale,exhibited superior stability owing to the renewal micro-nano *** retained the superhydrophobicity even if it was treated by rubbing for 1500 ***,it had outstanding photo-thermal and Joule-heating performance,because of the strong solar absorption and high electrical conductivity of MWCNT and *** provided both passive anti-icing and active deicing ***,it could achieve all-weather anti-icing for wind power generators under sunlight and low voltage *** facile preparation method and multifunctional renewable superhydrophobic coating hold great application prospects.

关键词： superhydrophobic coating cellulose hybrid nanomaterials anti-icing

Understanding cellulose dissolution： effect of the cation and anion structure of ionic liquids on the solubility of cellulose

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Science China Chemistry 2016年第11期59卷 1421-1429页

作者： jinming zhang Lili Xu Jian Yu Jin Wu Xiaoyu zhang Jiasong He Jun zhang Beijing National Laboratory for Molecular Sciences CAS Key Laboratory of Engineering Plastics Institute of Chemistry Chinese Academy of Sciences Beijing 100190 China Shandong Henglian New Materials Co. Ltd. Weifang 261061 China

The effect of ionic liquids(ILs) on the solubility of cellulose was investigated by changing their anions and cations. The structural variation included 11 kinds of cations in combination with 4 kinds of anions. The interaction between the IL and cellobiose, the repeating unit of cellulose, was clarified through nuclear magnetic resonance(NMR) spectroscopy. The reason for different dissolving capabilities of various ILs was revealed. The hydrogen bonding interaction between the IL and hydroxyl was the major force for cellulose dissolution. Both the anion and cation in the IL formed hydrogen bonds with cellulose. Anions associated with hydrogen atoms of hydroxyls, and cations favored the formation of hydrogen bonds with oxygen atoms of hydroxyls by utilizing activated protons in imidazolium ring. Weakening of either the hydrogen bonding interaction between the anion and cellulose, or that between the cation and cellulose, or both, decreases the capability of ILs to dissolve cellulose.

关键词： cellulose ionic liquids dissolution mechanism cellobiose

Click Modification for Polysaccharides via Novel Tunnel Transmission Phenomenon in Ionic Liquids

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Research 2022年第2期2022卷 315-322页

作者： Yan Zhou jinming zhang Yaohui Cheng Xin zhang Jin Wu Jun zhang CAS Key Laboratory of Enginering Plastic CAS Research/Education Center for Excllence in Molecular SciencesInstitte of ChemistryChinese Academy of Sciences(CAS)Beijing 100190China University of Chinese Academy 0f Sciences Bejing 10049China

It is extremely dificult toachievearapid and effcient modifcationofnatural polysaccharides,due tothe intrinsicstrong hydrogen bonding networks and the slow mass transfer process during the reaction ***,we found a fascinating anion-tunnel transmission phenomenon in the imidazolium-based ionic liquids with carboxylate anions.A novel click esterification of natural polysaccharides thus was demonstrated undera catalyst-free condition within a very short reaction time of15min at *** a super-rapid and highly eficient modification strategy is available for various polysaccharides(clluoe,starchinulin,pululan,dextranand xylan),difrentesterifcatonreactions(acetication,propionation benzoylation,and cyclohexylformylation),and high concentrations,claiming a revolutionary potential in polysaccharide chemistry industries.

关键词： process bonding catalyst

Comment on "Balance recovery control for biped robot based on reaction null space method"

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Control Theory and Technology 2010年第4期8卷 548-548页

作者： Baoping Wang, Renxi Hu, jinming zhang and Chuangfeng Huai Tokyo City University Tokyo Japan

Dear Editor,I am coauthor of the paper entitled "Balance control of a humanoid robot based on the reaction null space method" by Akinori Nishio,Kentaro Takahashi and Dragomir ***,published on pages 1996-2001

关键词： Comment on Balance recovery control for biped robot based on reaction null space method

Sustainable, thermoplastic and hydrophobic coating from natural cellulose and cinnamon to fabricate eco-friendly catering packaging

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Green Energy & Environment 2024年第5期9卷 927-936页

作者： Rumeng Xu Chunchun Yin Jingxuan You jinming zhang Qinyong Mi Jin Wu Jun zhang CAS Key Laboratory of Engineering Plastics Institute of ChemistryChinese Academy of Sciences(CAS)Beijing100190China University of Chinese Academy of Sciences Beijing100049China

Non-degradable polymers cause serious environmental pollution problem,such as the widely-used while unrecyclable coatings which signiﬁcantly affect the overall degradation performance of *** is imperative and attractive to develop biodegradable functional ***,we proposed a novel strategy to successfully prepare biodegradable,thermoplastic and hydrophobic coatings with high transparence and biosafety by weakening the interchain interactions between cellulose *** natural cellulose and cinnamic acid were as raw *** reducing the degree of polymerization(DP)of cellulose and regulating the degree of substitution(DS)of cinnamate moiety,the obtained cellulose cinnamate(CC)exhibited not only the thermalﬂow behavior but also good biodegradability,which solves the conﬂict between the thermoplasticity and biodegradability in cellulose-based *** glass transition temperature(T_(g))and thermalﬂow temperature(T_(f))of the CC could be adjusted in a range of 150–200℃ and 180–210℃,*** CC with DS<1.2 and DP≤100 degraded more than 60%after an enzyme treatment for 7 days,and degraded more than 80%after a composting treatment for 42 ***,CC had no toxicity to human epidermal cells even at a high concentration(0.5 mg mL^(-1)).In addition,CC could be easily fabricated into multifunctional coating with high hydrophobicity,thermal adhesion and high ***,after combining with cellophane and paperboard,CC coating with low DP and DS could be used to prepare fully-biodegradable heat-sealing packaging,art paper,paper cups,paper straws and food packaging boxes.

关键词： Thermoplastic coating Bio-degradable adhesive Natural products Cellulose Eco-friendly packaging