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印刷装备齿轮系统优化设计及动态特性研究综述

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包装工程 2024年第17期45卷 189-199页

作者：窦水海刘玉鑫王乐孙兆永王兆华林兆江杜艳平北京印刷学院机电工程学院北京102600 北京印刷学院新闻出版领域关键技术应用研究与服务综合实验室北京102600 北京印刷学院基础教育学院应用物理与波动工程实验室北京102600 唐山元创自动化科技股份有限公司河北省纸制品整饰成型智能装备技术创新中心河北唐山064100

目的齿轮系统作为印刷装备核心子系统之一,其优化设计直接影响着印刷装备的动态特性,进而对印品质量产生重要影响,因此亟须对其研究进展进行综述。方法通过文献综述法,梳理总结印刷装备齿轮系统动力学建模方法、优化设计及动态特性,以... 详细信息

目的齿轮系统作为印刷装备核心子系统之一,其优化设计直接影响着印刷装备的动态特性,进而对印品质量产生重要影响,因此亟须对其研究进展进行综述。方法通过文献综述法,梳理总结印刷装备齿轮系统动力学建模方法、优化设计及动态特性,以及与印品质量之间的关系等方面的研究成果,归纳概括各研究方法及其适应性,并展望未来的研究方向。结果目前,针对印刷装备复杂齿轮系统精细化动力学建模方法及运行稳定性分析的研究相对匮乏,针对印刷装备齿轮传动系统、执行系统、结构系统动力学建模与优化设计中的耦合作用的研究相对较少,针对印刷装备复杂齿轮系统的动态特性与印品质量指标之间的关系规律的研究相对缺乏,这些将成为未来的研究重点。结论采用高精度多物理场仿真技术有望进一步对印刷装备齿轮系统进行精细化、复杂性建模,采用拓扑优化算法可以满足印刷装备齿轮系统高稳定性、高耦合性优化设计的需求,采用深度学习方法能够挖掘动态特性与印品质量评价指标的关联规律,可为高端印刷装备关键自主可控技术的研发攻关提供支撑。

关键词：印刷装备齿轮系统动力学建模优化设计

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5-羟甲基糠醛的急性毒性研究

饲料工业 2024年第18期45卷 83-92页

作者：李松达崔洪伟王昭华邵明珠安乐乐李松励中国农业科学院北京畜牧兽医研究所北京100193

实验旨在研究5-羟甲基糠醛(5-HMF)对昆明小鼠的急性毒性影响,初步评价产品对昆明小鼠的毒效应特征、靶器官和剂量-反应关系。选取80只SPF级雄性昆明小鼠,随机分为8组,每组10只。适应性饲养一周后,采用8种不同剂量的5-HMF溶液进行口服灌... 详细信息

实验旨在研究5-羟甲基糠醛(5-HMF)对昆明小鼠的急性毒性影响,初步评价产品对昆明小鼠的毒效应特征、靶器官和剂量-反应关系。选取80只SPF级雄性昆明小鼠,随机分为8组,每组10只。适应性饲养一周后,采用8种不同剂量的5-HMF溶液进行口服灌胃。结果表明,昆明小鼠灌胃给药后随剂量增加出现呼吸困难、急促,扎堆、眯眼,被毛竖立而后死亡,随着剂量降低,出现以上现象频率降低。体重方面,与对照组相比,药物对体重无明显影响。利用改良寇式法计算昆明小鼠5-HMF急性毒性LD_(50)为3152.800 mg/kg。存活动物组织病理学检查结果显示:5-HFM毒性靶向器官为肾脏,小叶间静脉旁间质见炎性细胞浸润。根据WHO口服外源毒物分级标准,5-HMF为低毒。

关键词： 5-羟甲基糠醛急性毒性毒效应特征昆明小鼠炎性细胞

基于MSCT三维影像联合logistic回归分析建立模型在肺腺癌亚型的临床预测价值及预后分析

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医学影像学杂志 2024年第7期34卷 38-41,46页

作者：陈武闵旭红宋彪王彬李源宋奇隆王召华安徽省胸科医院影像中心安徽合肥230000

目的探讨MSCT三维影像表现联合logistic回归分析并建立模型在肺腺癌亚型的临床预测价值及预后分析。方法选取经手术病理证实为肺浸润性腺癌且肿瘤最长径均≤3.0cm的206例患者临床资料与MSCT三维影像的定性、定量数据,根据肺腺癌亚型... 详细信息

目的探讨MSCT三维影像表现联合logistic回归分析并建立模型在肺腺癌亚型的临床预测价值及预后分析。方法选取经手术病理证实为肺浸润性腺癌且肿瘤最长径均≤3.0cm的206例患者临床资料与MSCT三维影像的定性、定量数据,根据肺腺癌亚型危险度分为MP/S+组(含有微乳头成分或实体成分组)和MP/S-组(不含有微乳头或实体成分组),两组进行比较分析,通过logistic回归分析筛选出独立预测因子并建立预测模型,然后绘制受试者工作特征(ROC)曲线对比两组IAC的效能,最后根据手术后有无邻近组织侵犯等得出其预后分析。结果 206例患者肿瘤最长径均≤3.0 cm,其中MP/S+组89例,MP/S-组117例,平均发病年龄分别为(59.0±9.5)岁、(60.6±10.3)岁,结节最长径、分叶征等在两组亚型分类之间差异无统计学意义(P>0.05);而实性成分占比>50%、毛刺征等在两组亚型分类之间差异有统计学意义(P50%为独立预测因素,而ROC曲线显示logistic模型预测价值高于各独立预测因素。结论通过MSCT三维影像定性、定量数据结合logistic建立模型可提高MP/S+组的诊断率,从而预测患者预后,提高生存期。

关键词：肺腺癌亚型预后实性成分体层摄影术 X线计算机

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Reversible and irreversible heat generation of NCA/Si–C pouch cell during electrochemical energy-storage process

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Journal of Energy Chemistry 2019年第2期28卷 95-102页

作者： Ying Bai Limin Li Yu Li Guanghai Chen Huichun Zhao zhaohua wang Chuan Wu Hongyun Ma Xinquan wang Hongyue Cui Jiang Zhou School of Materials Science and Engineering Beijing Institute of Technology Collaborative Innovation Center of Electric Vehicles in Beijing Lishen Research Institute Tianjin Lishen Battery Joint-stock Co.Ltd.

To meet the requirements of electronic vehicles(EVs) and hybrid electric vehicles(HEVs),the high energy density Li Ni_(0.8) Co_(0.15) Al_(0.05) O_2(NCA) cathode and Si–C anode have attracted more *** we report the thermal behaviors of NCA/Si–C pouch cell during the charge/discharge processes at different current *** total heat generations are derived from the surface temperature change during electrochemical Li+insertion/extraction in adiabatic *** reversible heat is determined by the entropic coefficients,which are related with open-circuit voltage at different temperatures; while the irreversible heat is determined by the internal resistance,which can be obtained via V–I characteristic,electrochemical impedance spectroscopy and hybrid pulse power characterization(HPPC).During the electrochemical process,the reversible heat contributes less than 10% to total heat generation; and the heat generated in charge process is less than that in discharge *** results of thermal behaviors analyses are conducive to understanding the safety management and paving the way for building a reliable thermal model of high energy density lithium ion battery.

关键词： Heat generation Internal resistance Reversible heat Irreversible heat Pouch cell

Geochemistry of Heavy Oil in the T Block,Oriente Basin and its Origin Mechanism

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Acta Geologica Sinica(English Edition) 2010年第2期84卷 406-414页

作者： HU Ying YIN Jiquan SU Yongdi XIE Yinfu wang Xiaoxia XIAO Gaojie YU zhaohua wang Li Research Institute of Petroleum Exploration and Development Beijing 100083 China

Exploration and development experience show that there is obvious oil gravity difference between the southern part and northern part of the ＂M1＂reservoir in the Fanny oil field in the slope of the Oriente Basin, Ecuador. The American Petroleum Institute Gravity （API） values of oils in the northern part are higher than the one in the southern part of the Fanny oil field, with the values of 20° and 10.0°-13.0°, respectively. So the primary purpose of this study was to analyze the heavy oil characteristics of biodegradation and the oil-oil correlation according to the biomarker data and the δ^13C signature of oil samples from T block. The results of the hydrocarbon gas chromatography fingermark and the inversion attribute characteristics indicated that there are fluid compartments between the ＂M1＂ reservoir of Fanny south. Finally, the models of oil-gas accumulation under the control of multiple-activities of complicated fault systems, as well as the origin of heavy oil, are contended. The early stage oils from the western part of the basin were biodegraded heavily in varying degrees in the whole basin, and the later stage oils were derived from the southern part in a large scale and were mature and lighter. Generally, oil mixing is the primary control of net oil properties, such as API gravity in Oriente Basin. We therefore predicted that the API gravity variation of oil pools radically depends on the injection amount of the later stage oil. Because of the shale barrier in the ＂M1＂reservoir of Fanny south, the later stage hydrocarbon could not pass through and contribute to increase the oil API value.

关键词： heavy oil geochemistry biomarker origin mechanism Oriente Basin

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WK12型矿用挖掘机提升机构优化设计

矿山机械 2024年第1期52卷 72-74页

作者：朱宴南赵炎龙靳润王朝华国家电投扎哈淖尔煤业有限公司内蒙古通辽029199 太原科技大学机械工程学院山西太原030024

矿用挖掘机广泛应用于露天矿的开采作业^([1]),据统计,全世界2/3的固体矿物资源采用露天开采,而露天采场中80%以上的剥离量和采掘量是用挖掘机械完成的。因此,矿用挖掘机是大型露天矿山开采的关键设备。矿用挖掘机工作过程分为铲斗插入... 详细信息

矿用挖掘机广泛应用于露天矿的开采作业^([1]),据统计,全世界2/3的固体矿物资源采用露天开采,而露天采场中80%以上的剥离量和采掘量是用挖掘机械完成的。因此,矿用挖掘机是大型露天矿山开采的关键设备。矿用挖掘机工作过程分为铲斗插入堆料、离开堆料、卸料、复位及行走5个动作,依靠推压、提升、回转、开斗、行走机构和其他辅助机构配合完成^([2])。其中,提升与推压机构配合完成铲斗插入堆料、离开堆料及卸料等动作^([3-4])。

关键词：挖掘机械行走机构辅助机构推压机构机构优化设计堆料露天采场剥离量

Generation of 601 fs pulse from an 8 kHz Nd:YVO_(4) picosecond laser by multi-pass-cell spectral broadening

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Chinese Optics Letters 2021年第9期19卷 116-120页

作者： Jiajun Song zhaohua wang Xianzhi wang Renchong Lü Hao Teng Jiangfeng Zhu Zhiyi Wei Beijing National Laboratory for Condensed Matter Physics Institute of PhysicsChinese Academy of SciencesBeijing 100190China University of Chinese Academy of Sciences Beijing 1000A9China School of Physics and Optoelectronic Engineering Xidian UniversityXi'an 710071China Songshan Lake Materials Laboratory Dongguan 523808China CAS Center for Excellence in Ultra-intense Laser Science Shanghai 201800China

We demonstrate nonlinear pulse compression of an 8 k Hz Nd:YVO4 picosecond laser using the multi-pass-cell(MPC) technique with fused silica as the nonlinear medium. The pulse duration is compressed from 12.5 ps to 601 fs, corresponding to a pulse shortening factor of 20.8. The output pulse energy is 154 μJ with an efficiency of 74.5%. To the best of our knowledge,this is the highest pulse compression ratio achieved in a single-stage MPC with bulk material as the nonlinear medium. The laser power stability and the beam quality(M2) before and after the MPC are also experimentally studied. Both the laser power stability and the beam quality are barely deteriorated by the MPC device.

关键词： multi-pass cell Nd:W04 compression ratio femtosecond laser

Protective effect of tanshinone Ⅱ A on signal transduction system protein kinase B in rats with myocardial hypertrophy

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Frontiers of Medicine 2009年第4期3卷 431-436页

作者： Enyuan TU Yongjun PAN Kang ZHENG zhaohua wang Qiansheng LIANG Guangtian YANG Department of Emergency Tongji HospitalTongji Medical CollegeHuazhong University of Science and TechnologyWuhan 430030China

The effects of tanshinone II A on cell signal transduction system protein kinase B in rats with myocardial hypertrophy induced by the abdominal aorta partial coarctation were *** models of myocardial hypertrophy were established by using abdom-inal aorta partial coarctation ***-eight rats were randomly divided into sham group(S group),model group(M group),valsartan treatment group(X group),low-dose tanshinone treatment group(LD group),medium-dose tanshinone treatment group(MD group),and high-dose tanshinone treatment group(HD group)(n=8 in each group).Left ventricular mass index(LVMI),left ventri-cular posterior wall(LVPW),and septal thickness(IVS)were detected by high frequency ***ﬁber diameter(MFD)was examined by Hematoxylin-Eosin(HE)staining,and the contents of phosphorylated protein kinase B(p-Akt)and p-Gsk3βin myocardium were assayed by Western *** results showed that compared with S group,the values of LVMI,LVPW,IVS and MFD were increased in other groups(P0.05),and there were no signiﬁcant differences between X group and tanshinone treatment groups(P>0.05).It was suggested that tanshinone II A could prevent myocardial hypertrophy by its action on the Akt signaling pathway.

关键词： tanshinoneⅡA myocardial hypertrophy rat protein kinase B abdominal aorta coarctation

Femtosecond laser user facility for application research on ultrafast science

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Chinese Physics B 2018年第7期27卷 66-71页

作者： zhaohua wang Shaobo Fang Hao Teng Hainian Han Xinkui He Zhiyi Wei Beijing National Laboratory for Condensed Matter Physics Institute of Physics Chinese Academy of Sciences Beijing 100190 China University of Chinese Academy of Sciences Beijing 100049 China

The advent of chirped-pulse amplification （CPA） has greatly advanced the field of ultrafast and ultra-intense laser technology. CPA has become an indispensable platform for multidisciplinary research, such as physics, chemistry, life sciences, and precision metrology. The femtosecond laser facility at the Synergic Extreme Condition User Facility （SECUF） is a comprehensive experimental platform with an advanced femtosecond laser source for ultrafast scientific research. It will provide an ultrafast scientific research system having a few-cycle pulse duration, wide spectral range, high energy, and high repetition rate for multipurpose applications.

关键词： femtosecond carrier envelope phase (CEP) chirped-pulse amplification (CPA) ultrafast spec-troscopy optical parametric amplifier (OPA)