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Novel Ship Propulsion System

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Chinese Journal of Mechanical Engineering 2009年第2期22卷 198-206页

作者： JI yulong sun Yuqing ZHANG Hongpeng ZHANG Yindong CHEN Haiquan School of Marine Engineering Dalian Maritime University Dalian 116026 China

As the development tends towards high-speed, large-scale and high-power, power of the ship main engine becomes larger and larger. This make the engine design and cabin arrangement become more and more difficult. Ship maneuverability becomes bad. A new ship propulsion system, integrated hydraulic propulsion （IHP）, is put forward to meet the development of modem ship. Principle of IHP system is discussed. Working condition matching characteristic of IHP ship is studied based on its matching characteristic charts. According to their propulsion principle, dynamic mathematic models of IHP ship and direct propulsion （DP） ship are developed. These two models are verified by test sailing and test stand data. Based on the software Matlab/Simulink, comparison research between IHP ship and DP ship is conducted. The results show that cabin arrangement of IHP ship is very flexible, working condition matching characteristic of IHP ship is good, the ratio of power to weight of IHP ship is larger than DP ship, and maneuverability is excellent. IHP system is suitable for engineering ship, superpower ship and warship, etc.

关键词： ship integrated hydraulic propulsion (IHP) ship propulsion system modeling and simulation working condition matching characteristic

Biodegradable lubricating mesoporous silica nanoparticles for osteoarthritis therapy

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Friction 2022年第1期10卷 68-79页

作者： Li WAN Yi WANG Xiaolong TAN yulong sun Jing LUO Hongyu ZHANG State Key Laboratory of Tribology Department of Mechanical EngineeringTsinghua UniversityBeijing 100084China College of Mining Guizhou UniversityGuiyang 550025China Beijing Research Institute of Automation for Machinery Industry Co. Ltd.Beijing 100120China

Osteoarthritis is characterized by lubrication failure of the articular cartilage and severe inflammation of the joint *** mesoporous silica nanoparticles(MSNs)have been developed for the treatment of osteoarthritis based on enhanced lubrication and local drug ***,MSNs are difficult to degrade in vivo in a short time,resulting in potential toxic effect due to *** this study,biodegradable MSNs(bMSNs)were prepared through an oil–water biphase stratification method,and modified with poly(2-methacryloyloxyethyl phosphocholine)(PMPC)to synthesize lubricating drug-loaded nanoparticles(bMSNs–NH_(2)@PMPC)by *** in vitro degradation test demonstrated that the bMSNs and bMSNs–NH_(2)@PMPC almost degraded within 7 *** tribiological test showed that the lubrication property of the bMSNs–NH2@PMPC was greatly improved,with a reduction of 50%in the friction coefficient(COF)compared with the *** was attributed to hydration lubrication mechanism by which a tenacious hydration layer is formed surrounding the zwitterionic headgroups(N+(CH_(3))^(3)and PO4-)in PMPC polyelectrolyte ***,the bMSNs–NH_(2)@PMPC maintained excellent lubrication property under degradation and achieved sustained drug release behavior compared with the *** summary,the biodegradable bMSNs–NH2@PMPC developed in this study with the properties of enhanced lubrication and drug delivery may be a promising approach for osteoarthritis therapy.

关键词： silica hydration property

Synthesis of articular cartilage-inspired branched polyelectrolyte polymer for enhanced lubrication

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Biosurface and Biotribology 2020年第3期6卷 82-86页

作者： Yixin Wang Li Wan yulong sun Hongyu Zhang State Key Laboratory of Tribology Department of Mechanical EngineeringTsinghua UniversityBeijing 100084People’s Republic of China College of Mining Guizhou UniversityGuiyang 550025People’s Republic of China

The superlubrication property of articular cartilage is attributed to the hydration lubrication *** involves the complexation of biomacromolecules with phosphatidylcholine lipids to form a lubricating boundary layer on the *** on this mechanism,a branched polyelectrolyte polymer-PEI-PMPC was synthesised in this study to enhance lubrication via tert-butyl hydroperoxide-initiated grafting polymerisation of 2-methacryloyloxyethyl phosphorylcholine(MPC)onto polyethyleneimine(PEI)with various molecular *** the characterisation of the polymer using nuclear magnetic resonance,a series of tribological tests were performed under different normal loads and different scan *** results showed that the PEI-PMPC polyelectrolyte polymer in aqueous solution could effectively reduce the friction coefficient and wear generation between the polyethylene ball and the silica ***,an improvement in the lubrication performance was detected for the PEI-PMPC polyelectrolyte polymer when high molecular weight PEI was used during the reaction,which was attributed to the formation of the hydration shells surrounding the zwitterionic charges of PMPC and the viscosity of the *** conclusion,the PEI-PMPC polyelectrolyte polymer developed herein was characterised by enhanced lubrication,and may be potentially used for biomedical applications such as intra-articular injection to restore joint lubrication.

关键词： mechanism electrolyte polymer

Influence of site-directed mutation of cytochrome b_5 Phe35 on the protein's structure and properties

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Chinese Science Bulletin 1998年第3期43卷 214-217页

作者： YAO Ping WANG Yunhua sun yulong XIE Yi HUANG Zhongxian Department of Chemistry Fudan UniversityShanghai 200433China Institute of Genetics Fudan UniversityShanghai 200433China.

Kinetic studies of the heme dissociation from the wild type and Phe35Tyr, Phe35Leu mutants of bovine liver microsomal ferricytochrome b 5 indicate that the oxidized Phe35Tyr mutant is more stable towards denaturant than wild type but Phe35Leu mutant proceeded with a different mechanism compared with wild type cytochrome b 5 and Phe35Tyr mutant protein. Because of the decrease of side chain volume in Phe35Leu mutant, a cavity produced in the interior of the protein may offer a channel for urea molecule to enter the hydrophobic pocket. When urea concentration is larger than 5 mol/L, the urea molecule may compete to coordinate the iron of heme with His39, that results in sharp increase of the rate of heme dissociation. The interaction between cytochrome b 5 and cytochrom c demonstrated that a 1:1 protein complex was formed between the two proteins. The binding constants of cytochrome b 5 with cytochrome c are: wild type K A=4.2(±0.01)×10 6(mol/L) -1 , Phe35Tyr K A=3.7(±0.01)×10 6(mol/L) -1 and Phe35Leu K A=4.7(±0.01)×10 6(mol/L) -1 respectively ( I =1 m mol/L, pH 7.0 soldium phosphate buffer, 25℃). These results clearly show that the mutation at Phe35 has no influence on the binding of cytochrome b 5 with cytochrome c and that the hydrophilic patch residues are not involved in the binding of cytochrome b 5 and cytochrome c.

关键词： cytochrome b_(5) cytochrome c site_directed mutation protein structure.

Li4-xSbxSn1-xS4 solid solutions for air-stable solid electrolytes

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Journal of Energy Chemistry 2020年第2期29卷 171-176页

作者： Zhuoran Zhang Jianxing Zhang yulong sun Huanhuan Jia Linfeng Peng Yunyang Zhang Jia Xie State Key Laboratory of Advanced Electromagnetic Engineering and Technology School of Electrical and Electronic EngineeringWuhan 430074HubeiChina State Key Laboratory of Materials Processing and Die & Mould Technology School of Materials Science and EngineeringHuazhong University of Science and TechnologyWuhan 430074HubeiChina

The sulfide solid electrolytes have the characteristics of high ionic conductivity and low grain boundary resistance, which make them suitable for bulk-type all-solid-state batteries. However, most of them suffer from poor stability in air. Here, we explore the air stable sulfide solid electrolytes in Li4-xSbxSn1-xS4 system. The solid solutions of Li4-xSbxSn1-xS4(0 ≤ x ≤ 0.5) can be formed in Li4-xSbxSn1-xS4 system. Li3.8 Sb0.2 Sn0.8 S4 achieves the highest ionic conductivity of 3.5 × 10-4 S cm-1 in this system,which is 5 times as that of Li4 Sn S4 and 3 orders of magnitude higher than that of Li3 Sb S4, respectively. Li3.8 Sb0.2 Sn0.8 S4 crystallizes into the same structure with high ionic conductivity phase of β-Li3 PS4. Moreover, Li3.8 Sb0.2 Sn0.8 S4 owns good stability in humid air. Matching with LiCoO2 and Li4 Ti5 O12,Li3.8 Sb0.2 Sn0.8 S4 exhibits the potential to be applied in all-solid-state batteries.

关键词： Solid electrolyte Air stable sulfide Li4SnS4,β-Li3PS4 All-solid-state battery

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数据中心节能设计分析

通信电源技术 2024年第5期41卷 110-113页

作者：王德慷孙玉龙王东柱浪潮软件集团有限公司山东济南250101

文章依托数据中心建设的经验,结合数据中心的能耗组成情况,分析数据中心的节能挑战。同时,从机房的规划选址、机房布局、制冷方式、供配电系统、照明系统以及运维管控等方面,结合新技术探讨数据中心机房的节能设计,以降低数据中心的能耗。

关键词：数据中心节能空调供配电照明

Circadian metabolism regulates the macrophage inflammatory response

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Life Metabolism 2022年第3期1卷 224-233页

作者： yulong sun Wenjiao Jiang Tiffany Horng School of Life Sciences and Technology ShanghaiTech UniversityShanghai 201210China

Macrophages are an integral part of the innate immune system and coordinate host defense to microbial infections,as well as shaping the remodeling response after tissue *** is now appreciated to be a powerful and pervasive regulator of the identity and function of *** exposure to microbial ligands,macrophage inflammatory activation and the associated induction of phagocytosis,inflammatory responses,and other host defense activities are supported by dynamic changes to cellular *** note,metabolic activity is robustly regulated in a circadian fashion,with many metabolic processes displaying peak activity in one phase of the circadian cycle and trough activity in an antiphase ***,we review recent findings suggesting that circadian metabolism influences macrophage activities and particularly the inflammatory ***,we summarize macrophage activities known to display time-of-day–dependent variation and their mechanistic ***,we review metabolic processes that have been shown to be rhythmically regulated in macrophages and discuss how such circadian metabolism affects or is likely to affect macrophage ***,we discuss the concept of entrainment of the macrophage clock,and consider how loss of rhythmic regulation of macrophage activities may contribute to pathophysiological conditions like shift work,obesity,and ***,we propose that circadian metabolism can be used to understand the rationale and mechanistic basis of dynamic regulation of inflammatory responses during infection.

关键词： macrophage metabolism circadian metabolism circadian rhythm immunometabolism circadian immunometabolism macrophage inflammatory responses

THE MECHANISM OF SEED DETERIORATION

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Journal of Northeast Forestry University 1993年第1期4卷 6-10页

作者： Liu Enju Feng yulong sun Hongzhi Northeast Forestry University 1. Northeast Forestry University China

Seed deterioration is an irresistible physiological phenomenon. The aim to study seed deterioration is to see if seed deterioration can be retarded artificially and the higher seed vigor of fine varieties be maintained. The change of seed deterioration occurs in almost every system, and affects many kinds of enzyme and almost all organcllc, as a result, the seed loses its vigor. The reason of seed deterioration and the lost of seed vigor are mainly studied and discussed in this paper. According to the external and internal two kinds of theory advanced by E. H. Roberts, Much deep discussions are made from the view of biochemistry.

关键词： Seed deterioration Deterioration Loses of vigor

Stability and Time-Step Constraints of Implicit-Explicit Runge-Kutta Methods for the Linearized Korteweg-de Vries Equation

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Communications on Applied Mathematics and Computation 2024年第1期6卷 658-687页

作者： Joseph Hunter Zheng sun yulong Xing Department of Mathematics The Ohio State UniversityColumbusOH43210USA Department of Mathematics The University of AlabamaTuscaloosaAL35487USA

This paper provides a study on the stability and time-step constraints of solving the linearized Korteweg-de Vries(KdV)equation,using implicit-explicit(IMEX)Runge-Kutta(RK)time integration methods combined with either finite difference(FD)or local discontinuous Galerkin(DG)spatial *** analyze the stability of the fully discrete scheme,on a uniform mesh with periodic boundary conditions,using the Fourier *** the linearized KdV equation,the IMEX schemes are stable under the standard Courant-Friedrichs-Lewy(CFL)conditionτ≤λ***,λis the CFL number,τis the time-step size,and h is the spatial mesh *** study several IMEX schemes and characterize their CFL number as a function ofθ=d/h^(2)with d being the dispersion coefficient,which leads to several interesting *** also investigate the asymptotic behaviors of the CFL number for sufficiently refined meshes and derive the necessary conditions for the asymptotic stability of the IMEX-RK *** numerical experiments are provided in the paper to illustrate the performance of IMEX methods under different time-step constraints.

关键词： Linearized Korteweg-de Vries(KdV)equation Implicit-explicit(IMEX)Runge-Kutta(RK)method Stability Courant-Friedrichs-Lewy(CFL)condition Finite difference(FD)method Local discontinuous Galerkin(DG)method