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Synthesis of novel 15-membered macrolide dimers

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Chinese Chemical Letters 2009年第8期20卷 931-934页

作者： Shu Tao Ma rui Xin Ma rui qing xian Bo Jiao School of Pharmaceutical Sciences Shandong University Jinan 250012 China Affiliated Hospital of Medical College Qingdao University Qingdao 266003 China Shandong Institute for Drug Control Jinan 250000 China

A series of novel dimers of 15-membered macrolides was synthesized and evaluated. The dimers exhibited excellent activity against erythromycin-susceptible S. pneumonia, but did not show any improved activity against erythromycin-resistant S. pneumoniae encoded by erm gene. ？2009 Shu Tao Ma. Published by Elsevier B.V. on behalf of Chinese Chemical Society. All fights reserved.

关键词： Macrolide Azithromycin derivatives D/mers Synthesis

Seeded growth of Ti-46Al-8Nb polysynthetically twinned crystals with an ultra-high elongation

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Journal of Materials Science & Technology 2020年第19期54卷 190-195页

作者： Hao Jin qing Jia Quangang xian Ronghua Liu Yuyou Cui Dongsheng Xu rui Yang Institute of Metal Research Chinese Academy of SciencesShenyang110016China University of Chinese Academy of Sciences Beijing100049China

Large size polysynthetically twinned crystals of Ti-46 Al-8 Nb alloy with a parallel lamellar microstructure were successfully prepared using a Ti-43 Al-3 Si seed by our new operation.A large amount of columnar B2 phase paralleling to the growth direction was found in the final lamellar *** growth rate(>30 mm/h)led to the failure of seeding *** on these results,a new mechanism is proposed to describe the seeding process of the hypo-peritectic Ti Al *** peritecticαphase is suggested to directly nucleate from the melt,and then act as nucleus for transformedαphase in the subsequentβtoα*** the higher growth rate,the appearance ofβphase secondary dendrites and homogeneous nucleation lead to the failure of seeding *** Nb addition leads to a large amount of residualβphase,and theseβdendrites finally evolve into B2 *** room temperature tensile elongation was measured to be 11.9-18.5%for Ti-46 Al-8 Nb PST crystals,which is the highest ever reported value for Ti Al based alloys.

关键词： TiAl alloys Polysynthetically twinned crystals Peritectic solidification Seeded growth Ductility

Design and preliminary test of tritiated water online detector system based on plastic scintillators

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Nuclear Science and Techniques 2022年第10期33卷 68-78页

作者： Chun-Hui Dong Kai-Yong Liao rui-Yang Xu Hong-Wu Liu qing-xian Zhang Chengdu University of Technology Chengdu 610059China

In this study,an online detector system based on plastic scintillators is designed to monitor the activity of tritiated water in the liquid effluents of nuclear power *** feasibility of the detector is verified via simulation on Geant4,and the optimal detector structure size is determined.A back-end electronics system is designed and an experimental measurement platform forβ-rays based on a ^(40)KCl solution is *** ^(40)KC solutions with different activities ranging from 10 to4500 Bq/L are measured,and 1300 V is determined as the optimal operating high voltage of the photomultiplier tubes.A linear fit is performed in 10-min counts,and the maximum linear goodness of fit(R^(2))achieved is ***-term stability measurements are performed for two detectors,one filled with air and the other with a ^(40)KCl solution exhibiting an activity of 2000 Bq/*** relative deviation of the counts of the detector system every 10 min is 0.998%when the ^(40)KCl solution is used,and the maximum Gaussian R^(2) of the counts is 0.9849.

关键词： Tritiated water Geant4 Plastic scintillator Electronics system

Exact Travelling Wave Solutions of Discrete Planar Velocity Boltzmann Models

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Chinese Physics Letters 1997年第8期14卷 561-564页

作者： LÜ xian-qing Department of Applied Mathematics Tsinghua UniversityBeijing 100084

By investigating the discrete planar Boltzmann models:the square 4-velocity and the hexagonal 6-velocity models,exact travelling wave solutions can be studied in a concise *** their exact travelling wave solutions can only be monotonic travelling *** conclusions of the precursors need *** suggests a general method for obtaining nontrivial exact solutions for the similar discrete Boltzmann equation.

关键词： equation. wave. travelling

Static recrystallization behavior of 25CrMo4 mirror plate steel during two-pass hot deformation

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Journal of Iron and Steel Research International 2017年第2期24卷 222-228页

作者： Peng Zhou qing-xian Ma Department of Mechanical Engineering Tsinghua University Beijing 100084 China Key Laboratory for Advanced Materials Processing Technology of Ministry of Education Tsinghua University Beijing 100084 China

The static recrystallization behavior of 25CrMo4 mirror plate steel has been determined by hot compression testing on a Gleeble 1500 thermal mechanical simulation tester. Compression tests were performed using double hit schedules at temperatures of 950-- 1 150 ~C, strain rates of 0.01--0.5 s-1 , and recrystallization time of 1--100 s. Results show that the kinetics of static recrystallization and the microstructural evolution were greatly influenced by the deformation parameters （deformation temperature, strain rate and pre strain） and the initial austenite grain size. Based on the experimental results, the kinetics model of static recrystallization has been generated and the comparison between the experimental results and the predicted results has been carried out. It is shown that the predicted results were in good agreement with the experimental results.

关键词： Hot deformation Static recrystallization 25CrMo4 Kinetics equation Microstructure

Molecular Dynamics Simulations and Experimental Investigations of Atomic Diffusion Behavior at Bonding Interface in an Explosively Welded Al/Mg Alloy Composite Plate

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Acta Metallurgica Sinica(English Letters) 2017年第10期30卷 983-991页

作者： Ting-Ting Zhang Wen-xian Wang Jun Zhou Xiao-qing Cao rui-Shan Xie Yi Wei College of Materials Science and Engineering Taiyuan University of Technology Shanxi Key Laboratory of Advanced Magnesium-Based Materials Ministry of Education Key Laboratory of Interface Science and Engineering in Advanced Materials Ministry of Education Department of Mechanical Engineering Pennsylvania State University ErieThe Behrend College Department of Mechanical Engineering Key Laboratory for Advanced Materials Processing TechnologyTsinghua University

In this study, 6061 aluminum alloy and AZ31 B magnesium alloy composite plate was fabricated through explosive welding. Molecular dynamics（MD） simulations were conducted to investigate atomic diffusion behavior at bonding interface in the AI/Mg composite plate. Corresponding experiments were conducted to validate the simulation results. The results show that diffusion coefficient of Mg atom is larger than that of A1 atom and the difference between these two coefficients becomes smaller with increasing collision velocity. The diffusion coefficient was found to depend on collision velocity and angle. It increases linearly with collision velocity when the collision angle is maintained constant at 10° and decreases linearly with collision angle when the collision velocity is maintained constantly at 440 m/s. Based on our MD simulation results and Fick＇s second law, a mathematical formula to calculate the thickness of diffusion layer was proposed and its validity was verified by relevant experiments. Transmission electron microscopy and energy-dispersive system were also used to investigate the atomic diffusion behavior at the bonding interface in the explosively welded 6061/AZ31B composite plate. The results show that there were obvious Al and Mg atom diffusion at the bonding interface,and the diffusion of magnesium atoms from magnesium alloy plate to aluminum alloy plate occurs much faster than the diffusion of aluminum atoms to the magnesium alloy plate. These findings from the current study can help to optimize the explosive welding process.

关键词： Al/Mg composite plate Explosive welding Molecular dynamics simulation Atomic diffusionbehavior

Dynamic Recrystallization Behavior and Processing Map Development of 25CrMo4 Mirror Plate Steel During Hot Deformation

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Acta Metallurgica Sinica(English Letters) 2017年第9期30卷 907-920页

作者： Peng Zhou qing.xian Ma Department of Mechanical Engineering TsinghuaUniversityBeijing 100084China Key Laboratory for Advanced Materials ProcessingTechnology of Ministry of Education Tsinghua University Beijing 100084China

The dynamic recrystallization behavior of 25CrMo4 steel was systematically investigated by compression deformation at different temperatures and strain rates on a Gleeble 1500 thermal mechanical simulation tester. The flow curves under different deformation conditions were obtained, and the effects of deformation temperature and strain rate on the appearance of the flow curves were discussed. Based on the experimental flow curves, the activation energy determined by regression analysis was Q = 337 kJ/mol, and the constitutive model was constructed. All the characteristic points of the flow curves were identified from the work hardening rate curves （θ= dσ/dε vs σ）, which were derived from the flow curves. Then, the kinetics model of dynamic recrystallization was determined by combining the Avrami equation with the stress loss resulted from the dynamic recrystallization. With the aid of the kinetics model, the effect of strain on the efficiency of power dissipation was discussed. Furthermore, the optimum parameters for the forging process were determined based on the processing maps.

关键词： 25CrMo4 steel Dynamic recrystallization Kinetics model Processing map

Resilient and Safe Platooning Control of Connected Automated Vehicles Against Intermittent Denial-of-Service Attacks

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IEEE/CAA Journal of Automatica Sinica 2023年第5期10卷 1234-1251页

作者： Xiaohua Ge qing-Long Han qing Wu xian-Ming Zhang the School of Science Computing and Engineering TechnologiesSwinburne University of TechnologyMelbourne VIC 3122Australia the School of Engineering and Technology Central Queensland UniversityRockhampton QLD 4701Australia

Connected automated vehicles(CAVs)serve as a promising enabler for future intelligent transportation systems because of their capabilities in improving traffic efficiency and driving safety,and reducing fuel consumption and vehicle emissions.A fundamental issue in CAVs is platooning control that empowers a convoy of CAVs to be cooperatively maneuvered with desired longitudinal spacings and identical velocities on *** paper addresses the issue of resilient and safe platooning control of CAVs subject to intermittent denial-of-service(DoS)attacks that disrupt vehicle-to-vehicle ***,a heterogeneous and uncertain vehicle longitudinal dynamic model is presented to accommodate a variety of uncertainties,including diverse vehicle masses and engine inertial delays,unknown and nonlinear resistance forces,and a dynamic platoon ***,a resilient and safe distributed longitudinal platooning control law is constructed with an aim to preserve simultaneous individual vehicle stability,attack resilience,platoon safety and ***,a numerically efficient offline design algorithm for determining the desired platoon control law is developed,under which the platoon resilience against DoS attacks can be maximized but the anticipated stability,safety and scalability requirements remain ***,extensive numerical experiments are provided to substantiate the efficacy of the proposed platooning method.

关键词： Connected automated vehicles(CAVs) cooperative adaptive cruise control denial-of-service(DoS)attacks resilient control vehicle platooning vehicle-to-vehicle communication

Liposomalα-cyperone targeting bone resorption surfaces suppresses osteoclast differentiation and osteoporosis progression via the PI3K/Akt axis

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Nano Research 2024年第4期17卷 2949-2959页

作者： Lin Yang Xueying An Wang Gong Wenshu Wu Bin Liu Xiaoyan Shao Yansi xian rui Peng Baosheng Guo qing Jiang Division of Sports Medicine and Adult Reconstructive Surgery Department of Orthopedic SurgeryNanjing Drum Tower Hospital Clinical College of Nanjing Medical University321 Zhongshan RoadNanjing 210008China Branch of National Clinical Research Center for Orthopedics Sports Medicine and RehabilitationNanjing 210008China State Key Laboratory of Pharmaceutical Biotechnology Medical SchoolNanjing University&Division of Sports Medicine and Adult Reconstructive SurgeryDepartment of Orthopedic SurgeryNanjing Drum Tower HospitalThe Affiliated Hospital of Nanjing University Medical SchoolNanjing 210008China

Osteoporosis is a metabolic dysregulation of bone that occurs mainly in postmenopausal women,and the hyperfunction of osteoclasts is the primary contributor to postmenopausal ***,the development of effective therapeutic drugs and precise delivery systems remains a challenge in the field of anti-absorption ***,we reported theα-cyperone(α-CYP)for anti-osteoporosis and developed a liposome-based nano-drug delivery system ofα-CYP,that specifically targets the bone resorption ***,we found that theα-CYP,one of the major sesquiterpenes of Cyperus rotundus L.,attenuated the progression of osteoporosis in ovariectomized(OVX)mice and down-regulated the expression of phosphorylated proteins of phosphoinositide 3-kinase(PI3K)and protein kinase B(Akt),causing down-regulation of osteoclast-related genes/proteins and curbing osteoclast ***,α-CYP reversed the activation of osteoclastic differentiation and enhanced osteoporosis-related proteins expression caused by PI3K/Akt agonist(YS-49).More importantly,we adopted the osteoclastic resorption surface targeting peptide Asp8 and constructed the liposome(lipαC@Asp8)to deliverα-CYP to osteoclasts and confirmed its anti-osteoporosis effect and enhanced osteoclast inhibition by blocking PI3K/Akt *** conclusion,this study demonstrated thatα-CYP inhibits osteoclast differentiation and osteoporosis development by silencing PI3K/Akt pathway,and the liposome targeting delivery systems loaded withα-CYP might provide a novel and effective strategy to treat osteoporosis.

关键词： osteoporosis α-cyperone osteoclast phosphoinositide 3-kinase/protein kinase B(PI3K/Akt) liposome