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The Tessellation Rule and Properties Programming of Origami Metasheets Built with a Mixture of Rigid and Non-Rigid Square-Twist Patterns

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Engineering 2022年第10期17卷 82-92页

作者： Jiayao Ma Shixi Zang Yan Chen zhong you Key Laboratory of Mechanism Theory and Equipment Design of the Ministry of Education Tianjin UniversityTianjin 300350China School of Mechanical Engineering Tianjin UniversityTianjin 300350China Department of Engineering Science University of OxfordOxford OX13PJUK

Metamaterials constructed from origami units of different types and behaviors could potentially offer a broader scope of mechanical properties than those formed from identical unit ***,the geometric design rules and property programming methods for such metamaterials have yet to be extensively *** this paper,we propose a new kind of origami metasheet by incorporating a family of different square-twist *** tessellation rule of these metasheets is established to allow compatible mountain-valley crease assignments and geometric parameters among neighboring *** demonstrate through experiments that the energy,initial peak force,and maximum stiffness of the metasheets can be obtained by a summation of the properties of the constitutional *** on this,we are able to program the mechanical properties of the metasheets over a wide range by varying the types and proportions of the units,as well as their geometric and material ***,for a metasheet with a fixed number of units,all the geometrically compatible tessellations can be folded out of the same pre-creased sheet material by simply changing the mountain-valley assignments,thereby allowing the properties of the metasheet to be re-programmed based on specific *** work could inspire a new class of programmable origami metamaterials for current and future mechanical and other engineering applications.

关键词： Origami metamaterials Metasheets Square-twist pattern Non-periodic tessellation Programmability

A fast ellipsoid model for asteroids inverted from lightcurves

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Research in Astronomy and Astrophysics 2013年第4期13卷 471-478页

作者： Xiao-Ping Lu Hai-Bin Zhao zhong you Faculty of Information Technology Macao University of Science and Technology Purple Mountain Observatory Chinese Academy of Sciences

Research about asteroids has recently attracted more and more attention, especially focusing on their physical structures, such as their spin axis, rotation period and shape. The long distance between observers on Earth and asteroids makes it impossible to directly calculate the shape and other parameters of asteroids, with the exception of Near Earth Asteroids and others that have passed by some spacecrafts. Photometric measurements are still generally the main way to obtain research data on asteroids, i.e. the lightcurves recording the brightness and positions of asteroids. Supposing that the shape of the asteroid is a triaxial ellipsoid with a stable spin, a new method is presented in this article to reconstruct the shape models of asteroids from the lightcurves, together with other physical parameters. By applying a special curvature function, the method calculates the brightness integration on a unit sphere and Lebedev quadrature is employed for the discretization. Finally, the method searches for the optimal solution by the Levenberg-Marquardt algorithm to minimize the residual of the brightness. By adopting this method, not only can related physical parameters of asteroids be obtained at a reasonable accuracy, but also a simple shape model of an ellipsoid can be generated for reconstructing a more sophisticated shape model.

关键词： ellipsoid model - lightcurves - photometric - shape: asteroids

A plastic indentation model for sandwich beams with metallic foam cores

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Acta Mechanica Sinica 2011年第6期27卷 963-966页

作者： zhong-you Xie Ji-Lin Yu Zhi-Jun Zheng CAS Key Laboratory of Mechanical Behavior and Design of Materials University of Science and Technology of China 230026 Hefei China Department of Civil and Architectural Engineering Tongling University 244000 Tongling China

Light weight high performance sandwich composite structures have been used extensively in various load bearing *** have shown that the indentation significantly reduces the load bearing capacity of sandwiched *** this paper,the indentation behavior of foam core sandwich beams without considering the globally axial and flexural deformation was analyzed using the principle of virtual velocities.A concisely theoretical solution of loading capacity and denting profile was *** denting load was found to be proportional to the square root of the denting depth.A finite element model was established to verify the prediction of the *** load-indentation curves and the profiles of the dented zone predicted by theoretical model and numerical simulation are in good agreement.

关键词： Indentation Sandwich beam Metallic foam

Synthesis and Crystal Structure of Bisaqua-[N,N'-bis(3,5-dichlorosalicylidene)-1,3-diaminopropano]zinc(II)

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Chinese Journal of Structural Chemistry 2006年第9期25卷 1043-1046页

作者： you zhong-Lu HAN Xiao WANG Jia CHI Jing-Yun Department of Chemistry and Chemical Engineering Liaoning Normal University Dalian 116029 China

The title mononuclear zinc（Ⅱ） complex [Zn（BCDP）（H2O）2] （BCDP = N,N＇-bis（3,5dichlorosalicylidene）-1,3-diaminopropane） was prepared and characterized by elemental analysis, 1R spectra and single-crystal X-ray diffraction. The crystal belongs to the orthorhombic system, space group Pnma with a = 7.887（1）, b = 23.788（2）, c = 10.295（4） A, Z= 4, V= 1931.5（8） ,A^3, Dc = 1.786 g/cm^3, Mr = 519.49, λ（MoKa） = 0.71073 A, μ = 1.853 mm^-1, F（000） = 1048, R = 0.0464 and wR = 0.0918. A total of 2273 unique reflections were collected, of which 1570 with 1 〉 2σ（I） were observed. The molecule of the complex has crystallographic mirror symmetry. The Zn atom is sixcoordinated in an octahedral geometry. In the crystal, the molecules are linked through intermolecular O-H…O and O-H…Cl hydrogen bonds, forming chains running along the a axis.

关键词： Schiff base zinc crystal structure hydrogen bond

Folding of Tubular Waterbomb

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Research 2020年第1期2020卷 158-165页

作者： Jiayao Ma Huijuan Feng Yan Chen Degao Hou zhong you Key Laboratory of Mechanism Theory and Equipment Design of Ministry of Education Tianjin University135 Yaguan RoadTianjin 300350China School of Mechanical Engineering Tianjin University135 Yaguan RoadTianjin 300350China Department of Engineering Science University of OxfordParks RoadOxford OX13PJUK

Origami has recently emerged as a promising building block of mechanical metamaterials because it offers a purely geometric design approach independent of scale and constituent *** folding mechanics of origami-inspired metamaterials,i.e.,whether the deformation involves only rotation of crease lines(rigid origami)or both crease rotation and facet distortion(nonrigid origami),is critical for fine-tuning their mechanical properties yet very difficult to determine for origami patterns with complex ***,we characterize the folding of tubular waterbomb using a combined kinematic and structural *** for the first time uncover that a waterbomb tube can undergo a mixed mode involving both rigid origami motion and nonrigid structural deformation,and the transition between them can lead to a substantial change in the ***,we derive theoretically the range of geometric parameters for the transition to occur,which paves the road to program the mechanical properties of the waterbomb *** expect that such analysis and design approach will be applicable to more general origami patterns to create innovative programmable metamaterials,serving for a wide range of applications including aerospace systems,soft robotics,morphing structures,and medical devices.

关键词： deformation rotation rigid

Synthesis of Novel 3-Aryl Isoindolinone Derivatives

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Chemical Research in Chinese Universities 2013年第3期29卷 487-494页

作者： HU Chen-ming ZHENG Lian-you PEI Ya-zhong BAI Xu Center for Combinatorial Chemistry and Drug Discovery College of Chemistry and School of Pharmaceutical Sciences Jilin University Changchun 130021 P. R. China

A library of novel 3-aryl isoindolinone derivatives with aromatic amino acid derivative fragments was designed and synthesized. Two synthetic routes were employed to construct 3-aryl isoindolinone ring system for diff... 详细信息

关键词： Molecular library 3-Aryl isoindolinone Aromatic amino acid derivative

Analysis of the structure and expression of the 30K protein genes in silkworm, Bombyx mori

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Insect Science 2007年第1期14卷 5-14页

作者： QUAN SUN PING ZHAO YING LIN YONG HOU QING-you XIA zhong-HUAI XIANG The Key Laboratory of Sericulture of Agriculture Ministry College of Sericultur~ and Biotechnology Southwest UniversityChongqing China

A group of lipoproteins with molecular sizes of approximately 30 kDa, referred to as 30K proteins, axe synthesized in fat body cells in the fifth instar larvae of silkworm, Bombyx mori. Analyzing the silkworm genome and its expressed sequence tags （ESTs）, we found 10 genes encoding 30K proteins, which are mainly distributed in three subfamilies. Of these, seven coding proteins were found to harbor the degrading sites of 30kP protease A, although the number of degrading sites may be different. As some potential core promoters and regulatory elements were supposed to be essential for gene transcription, the expression profiles of these genes were examined by semi-quantitative reverse transcription polymerase chain reaction. Eight 30K protein genes were detected to express luxuriantly in the fat body, while two were hardly expressed. Such results suggest that these 30K proteins may have different functions, and their adjacent regulatory elements play a crucial role in regulating their transcription.

关键词： 30K protein Bombyx mori expression structure

Detection and Clinical Significance of DLC1 Gene Methylation in Serum DNA from Colorectal Cancer Patients

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Chinese Journal of Cancer Research 2011年第4期23卷 283-287页

作者： Ping-ping Wu Ji-hong Zou Ri-ning Tang Yao Yao Cheng-zhong you Deportment of Medical Oncology Jiangsu Cancer Hospital Nanjing 210009 China Department of Medicine Affiliated Zhongda Hospital 5outheast University Nanjing 210009 China Department of Genera/Surgery Jiangsu Cancer Hospital Nanjing 210009China Department of Genera/Surgery Affiliated Zhongda Hospital Southeast University Nanjing 210009 China

Objective: Deleted in liver cancer 1 (DLC1) is a new candidate tumor suppressor gene, whose down-regulation or even silence will result from promoter hypermethylation in various human cancers including colorectal cancer (CRC). The aim of this study is to evaluate the diagnostic role of DLC1 gene methylation in the serum DNA from CRC patients. Methods: This study enrolled 85 CRC patients and 45 patients with benign colorectal diseases. Methylation-specific polymerase chain reaction (MSP) was used to determine the promoter methylation status of DLC1 gene in serum DNA. The combination of DLC1 methylation and conventional tumor markers was further analyzed. Results: Hypermethylation of DLC1 was detected in 42.4% (36/85) of CRC serums, while seldom in the benign controls (8.9%, 4/45) (P<0.001). The aberrant DLC1 methylation in serum DNA was not associated with patients’ clinicopathological features and elevated CEA/CA19-9 levels. Furthermore, the combinational analysis of CEA, CA19-9 and DLC1 methylation showed a higher sensitivity and no reduced diagnostic specificity than CEA and CA19-9 combination for CRC diagnosis. Conclusion: The serum DLC1 methylation may be a promising biomarker for the early detection of CRC, which will further increase the diagnostic efficiency in combination with CEA and CA19-9.

关键词： DLC1 Colorectal cancer Methylation Biomarker

Proteomic analysis of the immune response of the silkworm infected by Escherichia coli and Bacillus bombyseptieus

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Insect Science 2012年第5期19卷 559-569页

作者： Xiao-Wu zhong Ping Zhao Yong Zou Hong-Yi Nie Qi-Ying Yi Qing-you Xia zhong-Huai Xiang The Key Sericultural Laboratory of Agriculture Ministry Southwest University Chongqing China

he silkworm, Bombyx mori, is an economically important insect with a 5 000-year history of domestication. During evolution, the silkworm has developed highly effective defenses against invasion and parasitization by microorganisms. In this study, two microorganisms Escherichia coli and Bacillus bombyseptieus were orally infected to silk- worm larvae. After infection with E. coli and B. bombyseptieus for 24 h, we investigated the polypeptide changes in the hemolymph, midgut and integument using two-dimensional gel electrophoresis and matrix-assisted laser desorption ionization time of flight mass spec- trometry. Forty-seven differentially expressed proteins were identified in these tissues. They belonged to a variety of functional classes, including immune proteins, metabolic proteins and structural proteins. Compared with controls, E. coli-infected silkworms showed 21 up- regulated proteins, 25 down-regulated proteins and lost one protein. After infection with B. bombyseptieus, silkworms showed 15 up-regulated proteins, 27 down-regulated pro- teins, lost three proteins and retained two proteins unchanged. We speculate that all these proteins may play a role in the silkworm immune response, although it is unclear why and how the two kinds of bacteria can so markedly alter expression of these proteins. These re- sults offer valuable insights for measuring the proteomic responses of the silkworm innate immune mechanism.

关键词： Bacillus bombyseptieus Escherichia coli immune response proteomics silkworm