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Substitution of the communication‑mediating domain and the interaction between modules in bacillomycin D produced by Bacillus amyloliquefaciens

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Systems Microbiology and Biomanufacturing 2023年第4期3卷 792-804页

作者： Ziyan Lv Wenjie Ma Zhaoxin lu Ping Zhang fengxia lu Haizhen Zhao Xiaomei Bie College of Food Science and Technology Nanjing Agricultural UniversityNanjing 210095People’s Republic of China

Bacillomycin D is a nonribosomal peptide produced by Bacillus amyloliquefaciens *** this study,the biosynthesis of bacillomycin D was mediated by replacing the intermodule donor,acceptor,and communication-mediating(COM)domain pairs and introducing the COM domain between the surfactin *** the homologous donor and the COM domain pair replacement strains eliminated the selective barrier of the original COM domain pair to a certain extent,resulting in a more flexible hybrid biosynthesis system that provides simultaneous biosynthesis of different lipopeptide *** synthesis of bacillomycin D in the homologous acceptor replacement strains was barely *** COM domains between the surfactin subunits cannot establish efficient communication between the bacillomycin D *** conclusion,the COM domains compatibility between the bacillomycin D modules are extremely strong,and the conserved amino acid residues in the acceptor domain are an important part of module–module interactions and efficient communication during bacillomycin D synthesis.

关键词： Bacillomycin D COM domain Surfactin Intermodule interaction Synthetase reprogramming

Nonlinear Dynamic Analysis of Planetary Gear Train System with Meshing Beyond Pitch Point

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Transactions of Nanjing University of Aeronautics and Astronautics 2020年第6期37卷 884-897页

作者： TANG Xin BAO Heyun lu fengxia JIN Guanghu National Key Laboratory of Science and Technology on Helicopter Transmission Nanjing University of Aeronautics and AstronauticsNanjing 210016P.R.China National Key Laboratory of Science and Technology on Helicopter Transmission AECC Hunan Aviation Powerplant Research InstituteZhuzhou 412002P.R.China

Nonlinear dynamic analysis was performed on a planetary gear transmission system with meshing beyond the pitch *** parameters of the planetary gear system were optimized,and a two-dimensional nonlinear dynamic model was established using the lumped-mass ***-varying meshing stiffness was calculated by the energy *** model consumes the backlash,bearing clearance,time-varying meshing stiffness,time-varying bearing stiffness,and time-varying friction *** time-varying bearing stiffness was calculated according to the Hertz contact *** load distribution among the gears was computed,and the time-varying friction coefficient was calculated according to elastohydrodynamic lubrication(EHL)*** dynamical equations were solved via numerical *** global bifurcation characteristics caused by the input speed,backlash,bearing clearance,and damping were *** system was in a chaotic state at natural frequencies or frequency *** system transitioned from a single-period state to a chaotic state with the increase of the *** bearing clearance of the sun gear had little influence on the bifurcation *** amplitude was restrained in the chaotic state as the damping ratio increased.

关键词： meshing beyond pitch point planetary gear system nonlinear time-varying bearing stiffness timevarying meshing stiffness multiple clearances bifurcation time-varying friction coefficient

Differences in Phosphorus Absorption and Utilization Efficiency of Soybean in Mature Period under Phosphorus Stress

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Agricultural Biotechnology 2014年第6期3卷 24-27,30页

作者： Yanli ZHANG Hongling QI fengxia lu Ming HAN Panpan WANG College of Life Science and Technology Mudanjiang Normal University

In this study, four phosphorus-inefficient soybean genotypes （1903, 1305, D17 and D18） and four phosphorus-efficient soybean genotypes （D31, D34, D37 and D38 ） were selected as experimental materials for soil culture experiment under high and low phosphorus treatments, to investigate the grain yield, phosphorus content, phosphorus uptake and the relationship between phosphorus utilization efficiency and phosphorus efficiency of soybean genotypes with different phos- phorus efficiency in mature period. According to the experimental results, under low phosphorus treatment, four phosphorus-efficient soybean genotypes exhibited significantly high phosphorus uptake in mature period, especially for D31 and D37; however, three phosphorus-efficient genotypes showed no advantages in adapta- bility of phosphorus utilization efficiency, while only I）31 exhibited high phosphorus utilization and absorption capacity. Correlation analysis and path analysis showed that phosphorus deficiency of soybean was mainly detemained by phosphorus absorption capacity, and phosphorus deficiency under （-P） treatment was sig- nificandy higher than （＋ P） treatment. Phosphorus uptake and phosphorus utilization efficiency posed great direct effects on phosphorus efficiency, and phosphorus uptake exhibited a greater contribution ; in addition, these two factors both posed small indirect effects. In mature period at reproductive growth stage, phosphorus absorption efficiency （phosphorus uptake） was the main variation source of phosphorus efficiency of various soybean genotypes in mature period. Therefore, strong phosphorus uptake and accumulation capacity of phosphorus-efficient soybean genotypes in mature period is an important nutrition foundation for the information of high grain yield.

关键词： Soybean Low phosphorus stress Phosphorus efficiency Absorption efficiency Utilization efficiency

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集成弹流润滑理论及CFD方法的轴承热特性

航空动力学报 2020年第6期35卷 1204-1211页

作者：陆凤霞王涛赵志强南京航空航天大学机电学院直升机传动技术国防科技重点实验室南京210016 中国航空工业集团有限公司金城南京机电液压工程研究中心南京211106

为能准确预测传动系统内部角接触球轴承在喷油润滑方式下的热特性,通过建立轴承热弹流润滑(EHL)模型,获得球体与滚道微观接触界面间的载荷及摩擦因数,并采用局部生热法计算生热量;应用计算流体动力学(CFD)方法建立轴承油气两相热流耦合... 详细信息

为能准确预测传动系统内部角接触球轴承在喷油润滑方式下的热特性,通过建立轴承热弹流润滑(EHL)模型,获得球体与滚道微观接触界面间的载荷及摩擦因数,并采用局部生热法计算生热量;应用计算流体动力学(CFD)方法建立轴承油气两相热流耦合模型,研究湍流模型及流体域边界条件的设置,分析喷油速度、喷嘴位置及含气率对轴承内部传热性能的影响。结果表明:结合热弹流润滑理论及CFD方法可预测轴承在不同工况条件、润滑参数、几何参数下的最佳喷油速度、喷嘴位置及含气率;喷油速度为5 m/s时,轴承内部最高温度较其他喷油速度降低了4.40%;喷嘴位置在轴承下方时,轴承内部最高温度较其他位置降低了4.30%;含气率为15%时,轴承内部最高温度较其他含气率降低了1.57%。

关键词：角接触球轴承弹流润滑(EHL) 局部生热法喷油润滑温度场

重型直升机前飞和悬停状态下主减速器舱流场与通风散热分析

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中南大学学报（自然科学版） 2021年第5期52卷 1473-1481页

作者：鲍和云侯潇男陆凤霞朱如鹏南京航空航天大学直升机传动技术重点实验室江苏南京210016

建立重型直升机主减速器舱模型,应用计算流体动力学(CFD)方法,模拟直升机的前飞状态,得到直升机前飞时的出口边界参考压力;对直升机前飞及悬停状态下的流场及温度场进行仿真分析,并考虑空气分配器、发电机通风管路和液压箱通风管路的影... 详细信息

建立重型直升机主减速器舱模型,应用计算流体动力学(CFD)方法,模拟直升机的前飞状态,得到直升机前飞时的出口边界参考压力;对直升机前飞及悬停状态下的流场及温度场进行仿真分析,并考虑空气分配器、发电机通风管路和液压箱通风管路的影响,比较前飞和悬停状态下主减速器舱空气流动状态和散热性能;探讨不同飞行高度和飞行速度下主减速器舱的空气流量和主减速器的散热功率。研究结果表明:在前飞状态下,直升机主减速器舱及舱体外表面温度更低,经由侧气口排出的空气大大增加,而上气口则由压力出口变为进口,涌入大量空气吹向主减速器舱;在前飞状态下,主减速器舱内空气流动速度更快,每组侧气口排出的空气量大致相等,主减速器舱周围空气流速加快,有利于主减速器的散热;随飞行高度和飞行速度增加,主减速器舱出口边界参考压力逐渐减小,主减速器舱空气流量和主减速器的散热功率逐渐增大。

关键词：重型直升机主减速器舱 CFD仿真流场温度场前飞悬停

节点外啮合行星轮系耦合动力学分析及试验验证

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中南大学学报（自然科学版） 2017年第8期48卷 2016-2023页

作者：鲍和云谭在银朱如鹏陆凤霞南京航空航天大学机电学院江苏南京210016

考虑太阳轮和行星架支承轴承的时变支承刚度,采用集中参数法建立节点外啮合行星齿轮系统齿轮-轴承耦合动力学模型,运用Rung-Kutta算法求解得到太阳轮和行星架的振动加速度响应;利用某型机械功率封闭试验台开展振动测试试验,基于小波变... 详细信息

考虑太阳轮和行星架支承轴承的时变支承刚度,采用集中参数法建立节点外啮合行星齿轮系统齿轮-轴承耦合动力学模型,运用Rung-Kutta算法求解得到太阳轮和行星架的振动加速度响应;利用某型机械功率封闭试验台开展振动测试试验,基于小波变换获得降噪信号。研究结果表明:支承刚度时变情况下的振动加速度幅值要大于支承刚度为定值时的加速度。横向振动的试验值与理论值的误差为16.27%,在允许范围内,而纵向振动受重力影响存在较大偏差,同时,考虑时变支承刚度求解得到的振动加速度更接近试验结果,即支承刚度的时变性不可忽略。

关键词：节点外啮合行星轮系滚动轴承耦合动力学试验验证

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老河口话的系属研究

柳州师专学报 2012年第6期27卷 39-41页

作者：路凤霞柳州师范高等专科学校广西柳州545004

老河口话原被划分为西南官话中的鄂北片。通过对老河口话入声字的计量研究,发现老河口话古入声今读阴平、阳平、上声、去声调值与临近中原官话调值相似,结合老河口话形成的历史,认为老河口话当归属中原官话。

关键词：入声字老河口话系属

考虑柔性齿圈的节点外啮合行星齿轮均载特性分析

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中南大学学报（自然科学版） 2016年第9期47卷 3005-3010页

作者：鲍和云周兴军朱如鹏陆凤霞南京航空航天大学机电学院江苏南京210016

建立一种考虑摩擦力、时变啮合刚度及阻尼、综合啮合误差及内齿圈柔性的节点外啮合行星齿轮平移-扭转动力学模型。推导系统多自由度的动力学微分方程组并采用四阶-五阶Runge-Kutta法求解方程,得到系统的振动响应。分析柔性齿圈、摩擦力... 详细信息

建立一种考虑摩擦力、时变啮合刚度及阻尼、综合啮合误差及内齿圈柔性的节点外啮合行星齿轮平移-扭转动力学模型。推导系统多自由度的动力学微分方程组并采用四阶-五阶Runge-Kutta法求解方程,得到系统的振动响应。分析柔性齿圈、摩擦力以及节点外系数对系统均载特性的影响。研究结果表明:表面摩擦力是系统内部激励源,会加剧系统振动,而对于节点外啮合行星齿轮,在啮合过程中摩擦力不换向,改善系统的振动。行星齿轮系统采用具有一定柔性的齿圈会提高系统内啮合载荷分配的均匀性,对于节点外啮合行星齿轮而言,均载系数随着节点外系数的变化呈现"U"型变化趋势。

关键词：柔性齿圈节点外啮合行星齿轮摩擦力均载

改革药品价格形成机制助推健康事业可持续发展

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中国医疗保险 2013年第3期 56-58页

作者：卢凤霞国家发改委药品价格评审中心北京100045

按照党的十八大及全面建成小康社会的要求,我国的健康事业需要走资源节约的道路。为此,药品价格形成机制改革应以促进资源节约为目标,以价值为导向,从药品成本评价、药品临床价值评价、药品质量价值评价等三方面具体着手,依靠科学的定... 详细信息

按照党的十八大及全面建成小康社会的要求,我国的健康事业需要走资源节约的道路。为此,药品价格形成机制改革应以促进资源节约为目标,以价值为导向,从药品成本评价、药品临床价值评价、药品质量价值评价等三方面具体着手,依靠科学的定价方法,建立合理的药品比价体系。

关键词：药品价格形成机制改革