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Defence Technology（防务技术） 2024年第3期33卷 125-133页

作者： Jinsong Tang linfang Qian Longmiao chen Guangsong chen Mingming Wang Guangzu Zhou Nanjing University of Science and Technology Nanjing 210094China Northwest Institute of Mechanical and Electrical Engineering Xianyang 712099China

In this paper,a dynamic modeling method of motor driven electromechanical system is presented,and the uncertainty quantification of mechanism motion is investigated based on this *** main contribution is to propose a novel mechanism-motor coupling dynamic modeling method,in which the relationship between mechanism motion and motor rotation is established according to the geometric coordination of the *** advantages of this include establishing intuitive coupling between the mechanism and motor,facilitating the discussion for the influence of both mechanical and electrical parameters on the mechanism,and enabling dynamic simulation with controller to take the randomness of the electric load into *** simulation considering feedback control of ammunition delivery system is carried out,and the feasibility of the model is verified *** on probability density evolution theory,we comprehensively discuss the effects of system parameters on mechanism motion from the perspective of uncertainty *** work can not only provide guidance for engineering design of ammunition delivery mechanism,but also provide theoretical support for modeling and uncertainty quantification research of mechatronics system.

关键词： Ammunition delivery system Electromechanical coupling dynamics Uncertainty quantification Generalized probability density evolution

High-dimensional uncertainty quantification of projectile motion in the barrel of a truck-mounted howitzer based on probability density evolution method

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Defence Technology（防务技术） 2024年第2期32卷 209-221页

作者： Mingming Wang linfang Qian Guangsong chen Tong Lin Junfei Shi Shijie Zhou Nanjing University of Science and Technology Nanjing 210094JiangsuChina Northwest Institute of Mechanical and Electrical Engineering Xianyang 712099ShaanxiChina Nanjing Vocational University of Industry Technology Nanjing 210023JiangsuChina

This paper proposed an efficient research method for high-dimensional uncertainty quantification of projectile motion in the barrel of a truck-mounted ***,the dynamic model of projectile motion is established considering the flexible deformation of the barrel and the interaction between the projectile and the ***,the accuracy of the dynamic model is verified based on the external ballistic projectile attitude test ***,the probability density evolution method(PDEM)is developed to high-dimensional uncertainty quantification of projectile *** engineering example highlights the results of the proposed method are consistent with the results obtained by the Monte Carlo Simulation(MCS).Finally,the influence of parameter uncertainty on the projectile disturbance at muzzle under different working conditions is *** results show that the disturbance of the pitch angular,pitch angular velocity and pitch angular of velocity decreases with the increase of launching angle,and the random parameter ranges of both the projectile and coupling model have similar influence on the disturbance of projectile angular motion at muzzle.

关键词： Truck-mounted howitzer Projectile motion Uncertainty quantification Probability density evolution method

Research on simulation of gun muzzle flow field empowered by artificial intelligence

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Defence Technology（防务技术） 2024年第2期32卷 196-208页

作者： Mengdi Zhou linfang Qian Congyong Cao Guangsong chen Jin Kong Ming-hao Tong School of Mechanical Engineering Nanjing University of Science and TechnologyNanjing210094China Northwest Institute of Mechanical and Electrical Engineering Xianyang712099ShaanxiChina School of Automation Nanjing University of Science and TechnologyNanjing210094China

Artificial intelligence technology is introduced into the simulation of muzzle flow field to improve its simulation efficiency in this paper.A data-physical fusion driven framework is ***,the known flow field data is used to initialize the model parameters,so that the parameters to be trained are close to the optimal *** physical prior knowledge is introduced into the training process so that the prediction results not only meet the known flow field information but also meet the physical conservation *** two examples,it is proved that the model under the fusion driven framework can solve the strongly nonlinear flow field problems,and has stronger generalization and *** proposed model is used to solve a muzzle flow field,and the safety clearance behind the barrel side is *** is pointed out that the shape of the safety clearance under different launch speeds is roughly the same,and the pressure disturbance in the area within 9.2 m behind the muzzle section exceeds the safety threshold,which is a dangerous *** with the CFD results shows that the calculation efficiency of the proposed model is greatly improved under the condition of the same calculation *** proposed model can quickly and accurately simulate the muzzle flow field under various launch conditions.

关键词： Muzzle flow field Artificial intelligence Deep learning Data-physical fusion driven Shock wave

The E3 ubiquitin ligase NEDD4-1 protects against acetaminophen-induced liver injury by targeting VDAC1 for degradation

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Acta Pharmaceutica Sinica B 2023年第4期13卷 1616-1630页

作者： Yiwei Zhu Lin Lei Xinghui Wang linfang chen Wei Li Jinxia Li chenchen Zhao Xiliang Du Yuxiang Song Wenwen Gao Guowen Liu Xinwei Li State Key Laboratory for Zoonotic Diseases Key Laboratory of Zoonosis ResearchMinistry of EducationCollege of Veterinary MedicineJilin UniversityChangchun 130062China

Acetaminophen(APAP)overdose is a major cause of liver *** precursor cell expressed developmentally downregulated 4—1(NEDD4-1)is an E3 ubiquitin ligase that has been implicated in the pathogenesis of numerous liver diseases;however,its role in APAP-induced liver injury(AILI)is ***,this study aimed to investigate the role of NEDD4-1 in the pathogenesis of *** found that NEDD4-1 was dramatically downregulated in response to APAP treatment in mouse livers and isolated mouse ***-specific NEDD4-1 knockout exacerbated APAP-induced mitochondrial damage and the resultant hepatocyte necrosis and liver injury,while hepatocyte-specific NEDD4-1 overexpression mitigated these pathological events both in vivo and in ***,hepatocyte NEDD4-1 deficiency led to marked accumulation of voltage-dependent anion channel 1(VDAC1)and increased VDAC1 ***,VDAC1 knockdown alleviated AILI and weakened the exacerbation of AILI caused by hepatocyte NEDD4-1 ***,NEDD4-1 was found to interact with the PPTY motif of VDAC1 through its WW domain and regulate K48-linked ubiquitination and degradation of *** present study indicates that NEDD4-1 is a suppressor of AILI and functions by regulating the degradation of VDAC1.

关键词： Acetaminophen NEDD4-1 VDAC1 Liver injury Hepatotoxicity Necrosis Mitochondrial damage Ubiquitination

18CrNiMo7-6钢的可控气氛高温渗碳工艺

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金属热处理 2022年第4期47卷 231-239页

作者：陈强陈林芳杨明华中车戚墅堰机车车辆工艺研究所有限公司江苏常州213011 中车戚墅堰机车有限公司江苏常州213011

基于机车用重载齿轮的热处理工艺要求,对18CrNiMo7-6钢进行920~1050℃的伪渗碳工艺处理,横向对比研究了试验钢经常规渗碳以及不同温度高温渗碳处理后的组织及力学性能;结合Aichelin计算机辅助模拟设计软件工艺模拟结果,制定高温渗碳工... 详细信息

基于机车用重载齿轮的热处理工艺要求,对18CrNiMo7-6钢进行920~1050℃的伪渗碳工艺处理,横向对比研究了试验钢经常规渗碳以及不同温度高温渗碳处理后的组织及力学性能;结合Aichelin计算机辅助模拟设计软件工艺模拟结果,制定高温渗碳工艺流程,对18CrNiMo7-6钢制齿轮进行高温渗碳处理,并与常规渗碳齿轮进行了组织及性能的对比研究。结果表明,与热处理前相比,经不同温度和时间的伪渗碳处理后,18CrNiMo7-6钢的综合力学性能均有所下降,但通过控制渗碳后的冷却过程,可以显著提高其最终热处理后综合力学性能;增加渗碳温度和碳势,可以大幅提高渗碳效率;对18CrNiMo7-6钢制齿轮进行最高温度1050℃高温渗碳,渗碳效率提高约65%,经高温渗碳后,齿轮组织、综合力学性能以及单齿弯曲疲劳强度相比于常规渗碳齿轮均未降低。

关键词： 18CrNiMo7-6钢转变行为高温渗碳力学性能单齿弯曲疲劳

高浓度非酯化脂肪酸诱导Ⅱ型酮病奶牛氧化应激

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吉林农业大学学报 2022年第2期44卷 170-175页

作者：李重邑陈琳方刘国文吉林大学动物医学学院长春130062

为探究Ⅱ型酮病奶牛的氧化应激状态及其诱因,采集健康和Ⅱ型酮病奶牛的血液样品,并分析氧化应激和肝损伤相关指标。结果表明:Ⅱ型酮病奶牛血液中NEFA、MDA和H_(2)O_(2)的含量高于健康奶牛,而CAT、SOD和GSH-Px的活性低于健康奶牛;此外,... 详细信息

为探究Ⅱ型酮病奶牛的氧化应激状态及其诱因,采集健康和Ⅱ型酮病奶牛的血液样品,并分析氧化应激和肝损伤相关指标。结果表明:Ⅱ型酮病奶牛血液中NEFA、MDA和H_(2)O_(2)的含量高于健康奶牛,而CAT、SOD和GSH-Px的活性低于健康奶牛;此外,肝损伤的标志物,AST、ALT、GGT和GLDH的活性均高于健康奶牛,说明Ⅱ型酮病表现为氧化应激和肝损伤。体外试验表明,高浓度NEFA(1.2 mmol/L)显著增加奶牛肝细胞中ROS的含量,引起肝细胞氧化应激并释放大量AST和ALT,而添加抗氧化剂NAC可以缓解NEFA引起的肝细胞氧化应激和损伤。这些结果说明高浓度NEFA通过诱导肝细胞氧化应激引起肝损伤,研究有助于明确Ⅱ型酮病的发病机理,为Ⅱ型酮病的防治奠定理论基础。

关键词： Ⅱ型酮病胰岛素抵抗氧化应激肝损伤

一种来自乳酸乳球菌的新型氨肽酶A的制备及特性分析

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生物工程学报 2023年第8期39卷 3494-3507页

作者：田鑫刘金洲何忠会陈琳方刘梦元湖北大学生命科学学院生物催化与酶工程国家重点实验室湖北武汉430062 湖北中医药大学检验学院湖北武汉430065

氨肽酶A(aminopeptidase A,Pep A)能特异性地水解N末端为谷氨酸(glutamic acid,Glu)或天冬氨酸(asparticacid,Asp)的肽链,提高蛋白质的水溶性和食物的风味,在食品工业和肉类加工中具有一定的应用前景。本研究采用全基因合成的方式获得... 详细信息

氨肽酶A(aminopeptidase A,Pep A)能特异性地水解N末端为谷氨酸(glutamic acid,Glu)或天冬氨酸(asparticacid,Asp)的肽链,提高蛋白质的水溶性和食物的风味,在食品工业和肉类加工中具有一定的应用前景。本研究采用全基因合成的方式获得了乳酸乳球菌(Lactococcus lactis ***)IL1403氨肽酶A(Lactococcus lactis-Pep A,Lc-Pep A)的编码基因,将该基因克隆并导入毕赤酵母(Pichia pastoris)GS115(His4),在毕赤酵母中实现了Lc-Pep A的高效分泌表达,表达产物经鉴定和纯化制备后,进行了生物学特性的分析。结果表明,Lc-Pep A具有较强的底物特异性,对2种底物谷氨酸对硝基苯胺(glutamicacid-p-nitroaniline,Glu-pNA)和天冬氨酸对硝基苯胺(aspartic acid-p-nitroaniline,Asp-pNA)具有相似的催化活力和酶动力学参数。Lc-Pep A是一种金属蛋白酶,最适反应温度为60℃,最适pH为8.0,具有较宽的热稳定性和酸碱稳定性。金属离子Co^(2+)、Mn^(2+)及Zn^(2+)等对酶活力具有不同程度的激活作用,而Ni^(2+)和Cu^(2+)对酶活力具有强烈的抑制作用。Lc-Pep A对常规蛋白酶抑制剂不敏感,但能被金属蛋白酶抑制剂、EDTA及二硫键还原剂抑制。这些研究为Lc-Pep A的生产和指导该酶的应用打下了坚实的基础。

关键词：氨肽酶A 乳酸乳球菌食品工业肉类加工

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基于改进拟连续算法的回转弹仓位置控制

兵工学报 2024年第5期45卷 1436-1448页

作者：陈冬钱林方陈志群陈龙淼邹权陈军华南京理工大学机械工程学院江苏南京210094 西北机电工程研究所陕西咸阳712099 中国电子科技集团公司第二十八研究所江苏南京210007 常州工学院航空与机械工程学院/飞行学院江苏常州213032

为提高大口径火炮自动装填过程中回转弹仓工作的精确性和鲁棒性,在分析现有拟连续算法相关研究内容的基础上,设计一种全新的改进拟连续控制器对回转弹仓进行位置控制。通过与滑模扰动观测器相结合,新控制器增益不依赖于系统扰动的不确... 详细信息

为提高大口径火炮自动装填过程中回转弹仓工作的精确性和鲁棒性,在分析现有拟连续算法相关研究内容的基础上,设计一种全新的改进拟连续控制器对回转弹仓进行位置控制。通过与滑模扰动观测器相结合,新控制器增益不依赖于系统扰动的不确定性边界,且不需引入额外的控制器参数,降低了控制器的设计和调试难度。通过Lyapunov方程验证控制器本身及闭环系统的稳定性。仿真和试验结果表明:新设计的控制器相对于已有拟连续算法具有优越性,在受到不确定时变负载和不确定参数扰动的情况下,新设计的改进控制器在应用于回转弹仓时,在趋近段可以获得更快的收敛速度,减小到位超调量,并在滑动段有效减弱抖振。

关键词：回转弹仓不确定扰动改进拟连续控制器滑模扰动观测器

IL-11对非酯化脂肪酸诱导奶牛肝细胞凋亡的影响

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中国兽医学报 2023年第6期43卷 1310-1314,1341页

作者：陈琳方刘梦林雷林刘国文吉林大学动物医学学院吉林长春130062

利用原代奶牛肝细胞进行体外试验,首先用0.0,0.6,1.2,2.4 mmol/L非酯化脂肪酸(non-esterified fatty acids,NEFA)处理奶牛原代肝细胞,通过Western blot检测各组IL-11和凋亡关键蛋白cleaved Caspase-3的表达,qRT-PCR检测IL-11 mRNA表达。结果显示,在高NEFA刺激下,1.2,2.4 mmol/L NEFA可显著升高IL-11和cleaved Caspase-3蛋白的表达,同时显著上调IL-11 mRNA表达;然后,通过短发夹RNA(sh-RNA)沉默IL-11,并用1.2 mmol/L NEFA处理奶牛原代肝细胞,通过Western blot检测IL-11和cleaved Caspase-3蛋白表达,qRT-PCR检测IL-11 mRNA表达,结果显示沉默IL-11可显著抑制NEFA诱导的cleaved Caspase-3的表达升高。结果表明,IL-11可通过促进cleaved Caspase-3的表达介导高NEFA诱导的奶牛原代肝细胞凋亡。

关键词：围产期奶牛非酯化脂肪酸白细胞介素11 凋亡

基于热化学烧蚀模型的身管寿命等效折算系数研究

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兵工学报 2024年第5期45卷 1426-1435页

作者：李延泽钱林方付佳维陈龙淼南京理工大学机械工程学院江苏南京210094 西北机电工程研究所陕西咸阳712009

针对当前等效全装药(Equivalent Full Charge,EFC)折算系数的国家军用标准预测值与实际测试结果差距较大的问题,基于热-化学烧蚀模型,研究不同工况下射击发数与EFC射击发数间的折算系数计算方法。射击一定发数后,假设身管内壁白层厚度... 详细信息

针对当前等效全装药(Equivalent Full Charge,EFC)折算系数的国家军用标准预测值与实际测试结果差距较大的问题,基于热-化学烧蚀模型,研究不同工况下射击发数与EFC射击发数间的折算系数计算方法。射击一定发数后,假设身管内壁白层厚度及成分随射击发数呈周期性变化,由质量扩散定律建立膛线起始部热-化学烧蚀量与火药燃气侵蚀性、内膛表面瞬态温度的关系。通过经典内弹道模型获得弹后空间火药燃气平均温度及内壁面强制对流换热系数,在考虑后效期高温燃气影响的基础上,建立身管内壁瞬态温度计算模型。以对内弹道过程有重要影响的射速、药量和药温为重点,计算不同射速、不同药号和不同药温下的身管内壁烧蚀量,并据此获得不同工况下的折算系数。研究发现,射速越快,装药质量越大,装药初始温度越高,单发射击造成的身管烧蚀越严重,其对应的EFC折算系数越大,其中强装药的EFC折算系数可达2.131。以某型155 mm火炮身管实弹射击数据为例,验证了新模型的合理性。

关键词：身管寿命等效全装药折算系数热化学烧蚀瞬态温度场

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