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Journal of Renewable Materials 2022年第4期10卷 993-1005页

作者： Ting Huang xin zhuo College of Civil Engineering and Architecture Zhejiang UniversityHangzhou310058China

The construction of grouting butt joints of bamboo tubes is simple and ***,when the joint is bent,the low tensile strength of the mortar easily leads to cracking of the mortar prior to the failure of the bamboo *** this paper,a comparative test of the bending capacity was performed on grouting butt joints reinforced by nonperforated,fully perforated,and semiperforated steel plates embedded in bamboo tubes to obtain the loaddisplacement curves and ultimate bearing capacity of various *** strengthening effect of CFRP pasted on bamboo tubes was also *** results show that the opening at the end of the steel plate is beneficial to resist the slip between the mortar and steel plate,while the complete section in the middle of the steel plate is conducive to making full use of the tensile strength of the steel ***,it is best to insert the semiperforated steel plate with openings in the end and without openings in the middle into the mortar to enhance the bending properties of the grouting butt joint,which can make the failure mode of the joint change from brittle failure of mortar to ductile compression failure of bamboo *** addition,pasting CFRP sheets on the external wall of the bamboo tube helps to reduce the tensile stress of the mortar,while increasing the width of the steel plate can increase the bending moment of inertia of the mixture of the steel plate and *** two complementary measures are very effective in delaying the cracking of the bamboo tube and improving the bending capacity of the joint.

关键词： Bamboo tube butt joint grouting connection perforated steel plate enhancement measure

Tensile force correction calculation method for prestressed construction of tension structures

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2008年第9期9卷 1201-1207页

作者： xin zhuo Guo-fa ZHANG Koichiro ISHIKAWA Dao-an LOU Department of Civtl Engmeermg Zhejiang University Hangzhou 310027 China Department of Architecture and Civil Engineering Fukui University Fukui 910-8507 Japan Zhejiang Zhancheng Construction Group Co. Ltd. Hangzhou 310005 China

Factors such as errors during the fabrication or construction of structural components and errors of calculation as- sumption or calculation methods, are very likely to cause serious deviation of many strings’ actual prestressing forces from the designed values during tension structure construction or service period, and further to threaten the safety and reliability of the structure. Aiming at relatively large errors of the prestressing force of strings in a tension structure construction or service period, this paper proposes a new finite element method (FEM), the "tensile force correction calculation method". Based on the measured prestressing forces of the strings, this new method applies the structure from the zero prestressing force status approach to the measured prestressing force status for the first phase, and from the measured prestressing force status approach to the designed prestressing force status for the second phase. The construction tensile force correction value for each string can be obtained by multi-iteration with FEM. Using the results of calculation, the strings’ tensile force correction by group and in batch will be methodic, simple and accurate. This new calculation method can be applied to the prestressed correction construction simulation analysis for tension structures.

关键词： Tension structures Prestressed construction High precision

Preparation,crystallization,and wetting of ZnO-Al_2O_3-B_2O_3-SiO_2 glass-ceramics for sealing to Kovar

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International Journal of Minerals,Metallurgy and Materials 2009年第5期16卷 586-591页

作者： Mao Wu xin-bo He zhuo-shen Shen Xuan-hui Qu School of Materials Science and Engineering University of Science and Technology Beijing Beijing 100083 China

A novel type of ZnO-Al2O3-B2O3-SiO2 glass-ceramics sealing to Kovar in electronic packaging was developed, whose thermal expansion coefficient and electrical resistance are 5.2× 10^-6/℃ and over 1×10^13 Ω·cm, respectively. The major crystalline phases in the glass-ceramic seals were ZnAl2O4, ZnB2O4, and NaSiAl2O4. The dielectric resistance of the glass-ceramic could be remarkably enhanced through the control of alkali metal ions into crystal lattices. It was found that crystallization happened first on the surface of the sample, leaving the amorphous phase in the inner, which made the glass suitable for sealing. The glass-ceramic showed better wetting on the Kovar surface, and sealing atmosphere and temperature had great effect on the wetting angle. Strong interracial bonding was obtained, which was mainly attributed to the interracial reaction between SiO2 and FeO or Fe3O4.

关键词： electronic packaging materials glass-ceramic crystallization wetting sealing

Electrochemical corrosion behavior of arc sprayed Zn-Al coatings

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中国有色金属学会会刊：英文版 2004年第Z1期14卷 443-445页

作者： LIU Yan ZHU Zi-xin CHEN Yong-xiong XU Bin-shi MA Shi-ning LI zhuo-xin National Key Laboratory for Remanufacturing Academy of Armored Forces Engineering Beijing 100072 China College of Materials Science and Engineering Beijng University of Technology Beijing 100022 China National Key Laboratory for Remanufacturing Academy of Armored Forces Engineering Beijing 100072 China National Key Laboratory for Remanufacturing Academy of Armored Forces Engineering Beijing 100072 China National Key Laboratory for Remanufacturing Academy of Armored Forces Engineering Beijing 100072 China School of Materials Science and Engineering Surface Engineering Research Institute CMES Beijing 100072 China College of Materials Science and Engineering Beijng University of Technology Beijing 100022 China

Cored wires and high velocity arc spraying (HVAS) technique were applied to produce high Al content Zn-Al alloy coatings on low carbon steel substrates. The electrochemical corrosion behaviors of Zn, Al and Zn-Al coatings were studied with potentiodynamic measurement in 5 % NaCl solution. Compared with pure Zn, pure Al and Zn-15Al coatings, Zn-26Al coatings show a higher corrosion resistance in salt solution. The potentiodynamic polarization tests show that the corrosion resistance of Zn-Al coatings increases as Al content is raised. Pure Al coating exhibits different electrochemical behaviors with other coatings. The corrosion initiated at the micro-pores of the coating and the underlying corrosion mechanism is very similar to that of the pitting corrosion.

关键词： coating electrochemical corrosion high velocity arc spraying potentiodynamic polarization

A 3-Node Co-Rotational Triangular Finite Element for Non-Smooth,Folded and Multi-Shell Laminated Composite Structures

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Computer Modeling in Engineering & Sciences 2021年第11期129卷 485-518页

作者： Zhongxue Li Jiawei Ji Loc Vu-Quoc Bassam A.Izzuddin xin zhuo Department of Civil Engineering Zhejiang UniversityHangzhou310058China Aerospace Engineering University of Illinois at Urbana-ChampaignUrbanaIL 61801USA Department of Civil and Environmental Engineering Imperial College LondonLondonSW72BUUK

Based on the first-order shear deformation theory,a 3-node co-rotational triangular finite element formulation is developed for large deformation modeling of non-smooth,folded and multi-shell laminated composite *** two smaller components of the mid-surface normal vector of shell at a node are defined as nodal rotational variables in the co-rotational local coordinate *** the global coordinate system,two smaller components of one vector,together with the smallest or second smallest component of another vector,of an orthogonal triad at a node on a non-smooth intersection of plates and/or shells are defined as rotational variables,whereas the two smaller components of the mid-surface normal vector at a node on the smooth part of the plate or shell(away from non-smooth intersections)are defined as rotational *** these vectorial rotational variables can be updated in an additive manner during an incremental solution procedure,and thus improve the computational efficiency in the nonlinear solution of these composite shell *** to the commutativity of all nodal variables in calculating of the second derivatives of the local nodal variables with respect to global nodal variables,and the second derivatives of the strain energy functional with respect to local nodal variables,symmetric tangent stiffness matrices in local and global coordinate systems are *** overcome shear locking,the assumed transverse shear strains obtained from the line-integration approach are *** reliability and computational accuracy of the present 3-node triangular shell finite element are verified through modeling two patch tests,several smooth and non-smooth laminated composite shells undergoing large displacements and large rotations.

关键词： Co-rotational approach 3-node triangular finite element laminated composite shells folded and multi-shell structures vectorial rotational variable line integration approach large deformation analysis

PTC/NTC Behavior of PVDF Composites Filled with GF and CF

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Chemical Research in Chinese Universities 2008年第5期24卷 648-652页

作者： WANG xin-lei ZHANG Guo LI Ji-xin LI zhuo-shi LIU Zhan-fang LIU Xiu-qi Key Laboratory of Automobile Materials Ministry of Education College of Materials Science and Engineering Jilin University. Changehun 130012 P. R. China

Conductive polyvinylidene fluoride（PVDF）matrix composites filled with graphited fiber（GF）or carbon fiber（CF）were prepared by the melt-mixing *** breakage and length distribution of the fibers in the polymer matrix were studied by scanning electron microscope（SEM）and optical microscope（OM）observations,respectively. The differences in the positive temperature coefficient（PTC）effects of the composites were mainly attributed to inter-fiber contact *** elimination of the negative temperature coefficient（NTC）effect for CF/PVDF composite was because of an increase in the viscosity of the polymer *** the same filler content,CF could be more effective,to eliminate the NTC effect when compared with *** of 2%CF（mass fraction）in the PVDF composite with 7%GF（mass fraction）could effectively eliminate the NTC phenomenon of the composite.

关键词： Polyvinylidene fluoride Graphited fiber Carbon fiber Positive temperature coefficient effect Negative temperature coefficient effect

TransRec++:Translation-based sequential recommendation with heterogeneous feedback

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Frontiers of Computer Science 2022年第2期16卷 190-192页

作者： zhuo-xin ZHAN Ming-Kai HE Wei-Ke PAN Zhong MING National Engineering Laboratory for Big Data System Computing Technology Shenzhen UniversityShenzhen 518060China College of Computer Science and Software Engineering Shenzhen UniversityShenzhen 518060China

1 Introduction Nowadays,recommender systems are widely used because of the information overload problem on the *** are a variety of feedback in recommender systems,such as explicit feedback,implicit feedback,sequential feedback,*** them,modeling of heterogeneous sequential feedback,which contains not only different types of feedback such as examinations and purchases but also the sequential information,is an emerging and important problem receiving more and more *** sequential feedback is relatively easy to be collected in a deployed system and is also able to provide more information than the homogeneous feedback,which is thus expected to be helpful in improving the recommendation accuracy.

关键词： feedback recommendation sequential

Control on the Morphology of ABA Amphiphilic Triblock Copolymer Micelles in Dioxane/Water Mixture Solvent

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Chinese Journal of Polymer Science 2018年第6期36卷 728-735页

作者： Yuan Gan Zhi-Da Wang zhuo-xin Lu Yan Shi Hong-Yi Tan Chang-Feng Yan Key Laboratory of Renewable Energy Guangzhou Institute of Energy ConversionChinese Academy of SciencesGuangzhou 510640China Guangdong Key Laboratory of New and Renewable Energy Research and Development Guangzhou 510640China University of Chinese Academy of Sciences Beijing 100049China

This work offers a typical understanding of the factors that govern the nanostructures of poly（4-vinyl pyridine）-b-polystyrene-bpoly（4-vinyl pyridine）（P4 VP-b-PS-b-P4 VP） block copolymers（BCs） in dioxane/water, in which water is a selective solvent for the P4 VP block. It is achieved through an investigation of the amphiphilic triblock copolymer micelles by variation of three different factors, including water content（above CWC but under the immobile concentration）, temperature（ranging from 20 °C to 80 °C）, and copolymer composition（low and high PS block length）. Transition of bead-like micelles to vesicles is observed with the increase of water content due to the increase of interfacial energy between the copolymer and the solvent. Effect of temperature superposed on that of water content results in various morphologies, such as beads, fibers, rods, capsules, toroids, lamellae, and vesicles. The interfacial tension between the BC and the solvent increases with the increase of water content but decreases with the increase of temperature, indicating that the micellar morphologies are resulted from the competitive interplay between the temperature and the water content and always change in a direction that decreases the interfacial energy. Based on the micellar structures obtained in this work and the effects of temperature superposed on water concentration, a diagram of phase evolution of different micellar morphologies is illustrated here, covering the temperature range from 20 °C to 80 °C and the water content changing from 20 vol% to 35 vol%. For the investigation of BC composition, morphological transition of vesicle-to-fiber, for high PS length, is observed as compared with bead-to-capsule for low PS length, as the temperature changes from 20 °C to 80 °C. Our research complements the protocols to control over the morphologies and the phase diagram describing P4 VP-b-PS-b-P4 VP micellar nanostructures in aqueous solution.

关键词： Micelles Morphological control Self-assembly Block copolymer

Simulation study on cuttings transport of the backreaming operation for long horizontal section wells

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Petroleum Science 2024年第2期21卷 1149-1170页

作者： Yu-Fei Chen Hui Zhang Wen-xin Wu Jun Li Yong Ouyang Zong-Yu Lu De-xin Ma Yong-Chuan Wu Jun-Bo Liu Ke-Rou Liu zhuo-xin Dong China University of Petroleum(Beijing) Beijing102249China Beijing Normal University at Zhuhai Experimental and Practical Education Innovation CenterZhuhai519087GuangdongChina Oil&Gas Technology Research Institute of PetroChina Changqing Oilfield Company Xi'an710016ShaanxiChina PetroChina xinjiang Oilfield Company Karamay834002XinjiangChina China Oilfield Services Ltd. Tianjin300459China

The backreaming operation plays a significant role in safe drilling for horizontal wellbores, while it may cause severe stuck pipe accidents. To lower the risk of the stuck pipe in backreaming operations, the mechanism of cuttings transport needs to be carefully investigated. In this research, a transient cuttings transport with multiple flow patterns model is developed to predict the evolution of cuttings transported in the annulus while backreaming. The established model can provide predictions of the distribution of cuttings bed along the wellbore considering the bulldozer effect caused by large-size drilling tools(LSDTs). The sensitivity analyses of the size of LSDTs, and backreaming operating parameters are conducted in Section 4. And a new theory is proposed to explain the mechanism of cuttings transport in the backreaming operation, in which both the bit and LSDTs have the “cleaning effect” and “plugging effect”.The results demonstrate that the cuttings bed in annuli is in a state of dynamic equilibrium, but the overall trend and the distribution pattern are obvious. First, larger diameters and longer drilling tools could lead to a higher risk of the stuck pipe. Second, we find that it is not the case that the higher flow rate is always better for hole cleaning, so three flow-rate intervals are discussed separately under the given conditions. When the “dangerous flow rate”(35 L/s in Case 4),the higher the flow rate, the better the cleaning effect of cuttings beds. Third, an interval of tripping velocity called “dangerous velocity” is proposed, in which the cuttings bed accumulation near the LSDTs is more serious than

关键词： Backreaming Stuck pipe Hole cleaning Transient solid transport Multiple flow patterns

Genome editing of PAR2 through targeted delivery of CRISPR-Cas9 system for alleviating acute lung inflammation via ERK/NLRP3/IL-1β and NO/iNOS signalling

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Acta Pharmaceutica Sinica B 2024年第3期14卷 1441-1456页

作者： xin zhuo Yue Wu Xiujuan Fu Jianbin Li Yuxin Xiang Xiaoyu Liang Canquan Mao Yuhong Jiang Sichuan Engineering Research Center for Biomimetic Synthesis of Natural Drugs School of Life Science and EngineeringSouthwest Jiaotong UniversityChengdu 610031China

Excessive and uncontrollable inflammatory responses in alveoli can dramatically exacerbate pulmonary disease progressions through vigorous cytokine releases,immune cell infiltration and protease-driven tissue *** is an urgent need to explore potential drug strategies for mitigating lung ***-activated receptor 2(PAR2)as a vital molecular target principally participates in various inflammatory diseases via intracellular signal ***,it has been rarely reported about the role of PAR2 in lung *** study applied CRISPR-Cas9 system encoding Cas9 and sg RNA(p Cas9-PAR2)for PAR2 knockout and fabricated an anionic human serum albuminbased nanoparticles to deliver p Cas9-PAR2 with superior inflammation-targeting efficiency and stability(TAP/p Cas9-PAR2).TAP/p Cas9-PAR2 robustly facilitated p Cas9-PAR2 to enter and transfect inflammatory cells,eliciting precise gene editing of PAR2 in vitro and in ***,PAR2 deficiency by TAP/p Cas9-PAR2 effectively and safely promoted macrophage polarization,suppressed proinflammatory cytokine releases and alleviated acute lung inflammation,uncovering a novel value of *** also revealed that PAR2-mediated pulmonary inflammation prevented by TAP/p Cas9-PAR2was mainly dependent on ERK-mediated NLRP3/IL-1β and NO/i NOS ***,this work indicated PAR2 as a novel target for lung inflammation and provided a potential nanodrug strategy for PAR2 deficiency in treating inflammatory diseases.

关键词： Protease-activated receptor 2(PAR2) CRISPR-Cas9 Gene editing Inflammation Acute lung inflammation NLRP3 Nanoparticles Drug delivery