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Synthesis of a New Two-dimensional Cd（Ⅱ） Coordination Compound by Benzotriazole-5-carboxylate Acid and 1,10-Phenanthroline and Its Crystal Structure and Characterization

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Chemical Research in Chinese Universities 2014年第3期30卷 347-351页

作者： wang junlong wang Dongjie LI Xing Faculty of Materials Science and Chemical Engineering Ningbo University Ningbo 315211 P. R. China

A mixed-ligand metal-organic complex [Cd（C7H3N3O2）（C12H8N2）]n was synthesized by cadmium（Ⅱ） nitrate, 1,10-phenanthroline（phen） and benzotriazole-5-carboxylate acid（H2btca）. Single crystal X-ray analysis indicates that complex 1 has a two-dimensional layer structure and crystallizes in an orthorhombic space group（Pbca）, with cell parameters, a=1.7422（6） nm, b=0.9264（3） nm, c=2.0729（7） nm, α=90°, β=90°,γ=90°, V=3.346（2） nm^3, Z=8. Each central Cd（Ⅱ） is six-coordinated by four N atoms, two of which are from 1,10-phenanthroline, and the other two from two different triazole nitrogen atoms and two O atoms from benzotriazole-5-carboxylate, forming a distorted octahedral geometry. Adjacent Cd（Ⅱ） centers are bridged by benzotriazole-5-carboxylate molecules to form a one-dimensional chain, which is further connected by the nitrogen atoms of btca^2- to form an extended two-dimensional wave-like layer, with OFF（offset face-to-face） stacking interactions between phen ligands in adjacent layers, which are helpful to forming the three-dimensional supramolecular structure.

关键词： Benzotriazole-5-carboxylate acid Cd(Ⅱ) complex Crystal structure Fluorescence

Numerical study on combustion efficiency of aluminum particles in solid rocket motor

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Chinese Journal of Aeronautics 2023年第5期36卷 66-77页

作者： junlong wang Ningfei wang Xiangrui ZOU Wei DONG Yintao ZHOU Dingjiang XIE Baolu SHI School of Aerospace Engineering Beijing Institute of TechnologyBeijing 100081China China Academy of Launch Vehicle Technology Beijing 100076China

The combustion of aluminum particles in solid rocket motor plays an important role in energy release of propellants. However, due to the limited residence time, aluminum particles may not be burned completely, thus hindering the improvement of specific impulse. This study aims to explore the characteristics of aluminum combustion efficiency and its influencing factors by experiments and numerical simulations, providing a guideline for engine performance improvement. As an input of simulation, the initial agglomerate size was measured by a high pressure system. Meanwhile, the size distribution of the particles in plume was measured by ground firing test to validate the numerical model. Then, a two-phase flow model coupling combustion of micro aluminum particle was developed, by which the detailed effects of particle size, detaching position and nozzle convergent section structure on aluminum combustion efficiency were explored. The results suggest that the average combustion temperature in the chamber drops with increasing initial particle size,while the maximum temperature increases slightly. In the tested motors, the aluminum particle burns completely as its diameter is smaller than 50 μm, and beyond 50 μm the combustion efficiency decreases obviously with the increase of initial size. As the diameter approaches to 75 μm, the combustion efficiency becomes more sensitive to particle size. The combustion efficiency of aluminum particle escaping from end-burning surfaces is significantly higher than that from internal burning surface, where the particle combustion efficiency decreases during approaching the convergent section. Furthermore, the combustion efficiency decreases slightly with increasing nozzle convergent section angle. And theoretically it is feasible to improve combustion efficiency of aluminum particles by designing the convergent profile of nozzle.

关键词： Aluminum Combustion efficiency Eulerian-Lagrangian Particle size Solid rocket motor

Experimental Study of Moso Bamboo to-Steel Connections with Embedded Grouting Materials

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Journal of Renewable Materials 2023年第3期11卷 1401-1423页

作者： Shidong Nie Wei Fu Hui wang Di Wu Min Liu junlong wang School of Civil Engineering Chongqing UniversityChongqing400045China Key Laboratory of New Technology for Construction of Cities in Mountain Area(Chongqing University) Ministry of EducationChongqing400045China Suzhou Newcity Investment and Development Co. Ltd.SuzhouChina Hangzhou Bangbo Technology Co. Ltd.HangzhouChina

Moso bamboos have attracted excessive attention as a renewable green building material to the concept of sustainable *** this paper,the 20 bolted Moso bamboo connection specimens with embedded steel plates and grouting materials were designed according to connection configurations with different bolt diameters and end distance of bolt holes,and their bearing capacities and failure modes were analyzed by static tension *** to the test results of all connectors,the failure modes of the specimens are divided into four categories,and the effects of bolt diameter and bolt hole end distance on the connection bearing capacity and failure mode are *** test results show that the deformation and failure process can be divided into four *** main influence factor of connector bearing capacity is bolt *** can be divided into four failure modes,and brittle failure can be avoided by adopting certain structural *** with grouting material can improve the bearing capacity of *** to the large variability of bamboo,further experiments are needed.

关键词： Moso bamboo connections embedded steel plates grouting materials bearing capacities failure modes

Effect of La on microstructure,mechanical properties and fracture behavior of Al/Mg bimetallic interface manufactured by compound casting

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Journal of Materials Science & Technology 2022年第10期105卷 214-225页

作者： Zheng Zhang Wenming Jiang Guangyu Li junlong wang Feng Guan Guoliang Jie Zitian Fan State Key Laboratory of Materials Processing and Die and Mould Technology School of Materials Science and EngineeringHuazhong University of Science and TechnologyWuhan 430074China State Key Laboratory for Advanced Metals and Materials University of Science and Technology BeijingBeijing 100083China

To improve the Al/Mg bimetallic interface,La was added into the Al/Mg bimetallic interface manufactured by a compound casting *** effect of La addition on the microstructure,mechanical properties and fracture behavior of the Al/Mg bimetallic interface and the formation mechanism of the interface were studied in ***_(11)La_(3),Al_(8)Mn_(4)La,Al_(20)Ti_(2)La,and other rare earth precipitates(RE precipitates)preferentially precipitated at the interface with La addition,while the number of the Al_(11)La_(3)and Al_(8)Mn_(4)La located in eutectic structure area(E area)gradually increased and aggregated in the interface with the increase of the La ***,the matrix structure in different areas of the Al/Mg interface changed in different degrees,and the eutectic structure and primaryγ(Mg_(17)Al_(12))dendrites in the E area were refned,but the intermetallic compounds area(IMC area)had no obvious *** the addition of the La,the interface was strengthened under the comprehensive effect of refnement strengthening and precipitation strengthening from the E *** the La content increased to 1.0%,the shear strength of the Al/Mg bimetal reached the maximum of 51.54 MPa,which was 30.95%higher than the group without La ***,with the further increase of the La content,the large area aggregation of the Al_(11)La_(3)and Al_(8)Mn_(4)La occurred in the interface,leading to the separation of the matrix structure of the E area and the decrease of the shear strength of the Al/Mg interface.

关键词： Compound casting Al-Mg intermetallic compounds Rare earth La Al/Mg interface Microstructure Mechanical properties

Preparation, interfacial regulation and strengthening of Mg/Al bimetal fabricated by compound casting: A review

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Journal of Magnesium and Alloys 2023年第9期11卷 3059-3098页

作者： Guangyu Li Wenming Jiang Feng Guan Zheng Zhang junlong wang Yang Yu Zitian Fan State Key Laboratory of Materials Processing and Die&Mould Technology School of Materials Science and EngineeringHuazhong University of Science and TechnologyWuhan 430074China

Mg/Al bimetal combines the advantages of both aluminum and magnesium and has broad application prospects in automotive, aerospace,weapons, digital products and so on. The compound casting has the characteristics of low cost, easy to achieve metallurgical combination and suitable for the preparation of complex bimetallic parts. However, bimetallic joint strength is low due to differences of physical properties between Al and Mg, oxide film on metallic surface and interfacial Al-Mg IMCs, which is closely related to the interfacial microstructure and properties. Therefore, how to control the interface of the bimetal to achieve performance enhancement is the focus and difficulty in this field. At present, there are mainly the following strengthening methods. First, the “zincate galvanizing” and “electrolytic polishing+anodic oxidation” technology were exert on the surface of Al alloy to remove and break the oxide film, which improved the wettability between Al and Mg. Second, the undesirable Al-Mg IMCs were reduce or elimination by adding the interlayers(Zn, Ni and Ni-Cu). Thirdly, the evolution process of interfacial microstructure was changed and fine strengthening phases were formed by adding Si element to Al alloy or rare earth element to Mg alloy. Fourthly, mechanical vibration and ultrasonic vibration were applied in the process of the filling and solidification to refine and homogenize the interfacial structure. Finally, some other methods, including secondary rolling, thermal modification, heat treatment and constructing exterior 3D morphology, also can be used to regulate the interfacial microstructure and compositions. The above strengthening methods can be used alone or in combination to achieve bimetallic strengthening. Finally, the future development direction of the Mg/Al bimetal is prospected, which provides some new ideas for the development and application of the Mg/Al bimetal.

关键词： Mg/Al bimetal Preparation Compound casting Interfacial regulation Interface strengthening Research progress

Effect of vibration on interfacial microstructure and mechanical properties of Mg/Al bimetal prepared by a novel compound casting

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Journal of Magnesium and Alloys 2022年第8期10卷 2296-2309页

作者： Feng Guan Wenming Jiang Guangyu Li Junwen Zhu junlong wang Guoliang Jie Zitian Fan State Key Laboratory of Materials Processing and Die&Mould Technology School of Materials Science and EngineeringHuazhong University of Science and TechnologyWuhan 430074China State Key Laboratory for Advanced Metals and Materials University of Science and Technology BeijingBeijing 100083China

In this work,a vibration was applied in the preparation of the Mg/Al bimetal by a novel compound casting in order to improve the mechanical properties of the Mg/Al bimetal,and the effect of the vibration on the interfacial microstructure and mechanical properties of the Mg/Al bimetal was *** results indicated that the vibration had a significant effect on the interfacial microstructure and mechanical properties of the Mg/Al bimetal,but it did not change the phase compositions of the interface,which was composed of layerⅠ(Al3Mg2+Mg2Si),layerⅡ(Al_(12)Mg_(17)+Mg_(2)Si)and layerⅢ(Al_(12)Mg_(17)/δ-Mg).Without vibration,the Mg_(2)Si phase with a needle-like morphology mainly aggregated in the layerⅡof the *** the application of the vibration,the SEM and EBSD analysis results showed that the Mg_(2)Si and Al3Mg2phases in the interface were obviously refined,and the distribution of the Mg_(2)Si became more uniform,due to the strong forced convection of the molten metal resulting from the *** TEM analysis indicated that the interface between the A_(l3)Mg_(2) and Mg_(2)Si phases was non-coherent,suggesting the Mg_(2)Si particles cannot act as a heterogeneous nucleation base during the solidification process of the *** to the Mg/Al bimetal without vibration,the shear strength of the Mg/Al bimetal with vibration increased by about 50%from 31.7 MPa on average to 47.5 MPa,and the hardness of the layer I of the interface increased,and the hardness of the layerⅢ*** fracture surface transformed from a flat fracture morphology without vibration to an irregular zigzag fracture morphology.

关键词： Mg/Al bimetal Vibration Compound casting Interfacial microstructure Bonding properties

Structural variation during dog domestication: insights from gray wolf and dhole genomes

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National Science Review 2019年第1期6卷 110-122页

作者： Guo-Dong wang Xiu-Juan Shao Bing Bai junlong wang Xiaobo wang Xue Cao Yan-Hu Liu Xuan wang Ting-Ting Yin Shao-Jie Zhang Yan Lu Zechong wang Lu wang Wenming Zhao Bing Zhang Jue Ruan Ya-Ping Zhang State Key Laboratory of Genetic Resources and Evolution Kunming Institute of ZoologyChinese Academy of Sciences Center for Excellence in Animal Evolution and Genetics Chinese Academy of Sciences Agricultural Genomics Institute Chinese Academy of Agricultural Sciences Medical Faculty Kunming University of Science and Technology Department of Pediatrics the First People's Hospital of Yunnan Province College of Pharmacology Soochow University Key Laboratory of Animal Models and Human Disease Mechanisms of the Chinese Academy of Sciences and Yunnan Province Kunming Institute of ZoologyChinese Academy of Sciences Department of Laboratory Animal Science Kunming Medical University Laboratory for Conservation and Utilization of Bio-Resources and Key Laboratory for Microbial Resources of the Ministry of Education Yunnan University Kunming College of Life Science University of Chinese Academy of Sciences Beijing Zoo Core Genomic Facility Beijing Institute of GenomicsChinese Academy of Sciences

Several processes like phenotypic evolution, disease susceptibility and environmental adaptations, which fashion the domestication of animals, are largely attributable to structural variations(SVs) in the ***, we present high-quality draft genomes of the gray wolf(Canis lupus) and dhole(Cuon alpinus) with scaffold N50 of 6.04 Mb and 3.96 Mb, respectively. Sequence alignment comprising genomes of three canid species reveals SVs specific to the dog, particularly 16 315 insertions, 2565 deletions, 443 repeats, 16 inversions and 15 translocations. Functional annotation of the dog SVs associated with genes indicates their enrichments in energy metabolisms, neurological processes and immune systems. Interestingly, we identify and verify at population level an insertion fully covering a copy of the AKR1 B1(Aldo-Keto Reductase Family 1 Member B) transcript. Transcriptome analysis reveals a high level of expression of the new AKR1 B1 copy in the small intestine and liver, implying an increase in de novo fatty acid synthesis and antioxidant ability in dog compared to gray wolf, likely in response to dietary shifts during the agricultural revolution. For the first time, we report a comprehensive analysis of the evolutionary dynamics of SVs during the domestication step of dogs. Our findings demonstrate that retroposition can birth new genes to facilitate domestication, and affirm the importance of large-scale genomic variants in domestication studies.

关键词： dog domestication genome assembly structural variation gray wolf dhole

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定期保障模式下舰船编队携行备件配置优化

系统工程理论与实践 2018年第9期38卷 2441-2448页

作者：阮旻智钱超王睿王俊龙海军工程大学舰船与海洋学院武汉430033 海军大连舰艇学院信息系统系大连116018

舰船编队海上任务期间,需要制定合理的携行备件方案以提高装备的战备完好性.针对海上定期保障模式下,将多层级复杂装备结构等效为单层级,提出一种备件需求分析与配置优化的近似方法,根据系统可靠性理论,建立了多阶段任务下的装备可用度... 详细信息

舰船编队海上任务期间,需要制定合理的携行备件方案以提高装备的战备完好性.针对海上定期保障模式下,将多层级复杂装备结构等效为单层级,提出一种备件需求分析与配置优化的近似方法,根据系统可靠性理论,建立了多阶段任务下的装备可用度评估模型,采用基于补给周期的分段求解方法.通过算例,采用边际优化算法得到携行备件优化方案,对模型结果进行了仿真验证,结果表明：模型计算结果与仿真结果吻合,两种取整方式下的方案费效比相当,采用定期保障模式能够提高备件供应效率,进一步增强备件方案的鲁棒性.

关键词：定期保障携行备件优化舰船编队可用度多层级

Cloning, expression and protective immunity evalua-tion of the full-length cDNA encoding succinate dehydrogenase iron-sulfur protein of Schistosoma japonicum

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Science China(Life Sciences) 2007年第2期50卷 221-227页

作者： YU junlong, wang ShiPing, LI WenKai, DAI Gan, XU ShaoRui, HE Zhuo, PENG XianChu, ZHOU SongHua & LIU XueQin Department of Parasitology, Xiangya School of Medicine, Central South University, Changsha 410078, China 1. Department of Parasitology Xiangya School of Medicine Central South University Changsha 410078 China

1071-bp fragment was obtained from the Schistosoma japonicum (Chinese strain) adult cDNA library after the 3′ and 5′ ends of the incomplete expression sequence tag (EST) of succinate dehydrogenase iron-sulfur protein of Schistosoma japonicum (SjSDISP) were amplified by the anchored PCR with 2 pairs of primers designed according to the EST of SjSDISP and the sequence of multiclone sites of the library vector. Sequence analysis indicated that the fragment was a full-length cDNA with a complete open reading frame (ORF), encoding 278 amino acid residues. The fragment was cloned into prokary- otic expression vector pQE30, and subsequently sequenced and expressed in Escherichia coli. SDS-PAGE and Western-blot analyses showed that the recombinant protein was about 32 kD and could be recognized by the polyclonal antisera from rabbits immunized with Schistosoma japonicum adult worm antigen. Compared with the FCA controls, mice vaccinated with rSjSDISP (test) or rSjGST (posi- tive control) all revealed high levels of specific antibody and significant reduction in worm burden, liver eggs per gram (LEPG), fecal eggs per gram (FEPG) and intrauterine eggs. These results suggest that SjSDISP may be a novel and partially protective vaccine candidate against schistosomiasis. In contrast to the worm burden reduction rate, the higher degree of egg reduction rate in the test group also sug- gested that SjSDISP vaccine may primarily play a role in anti-embryonation or anti-fecundity immunity.

关键词： Schistosoma japonicum iron-sulfur protein of succinate dehydrogenase cloning expression protective immunity