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旋流流动对水冲压发动机性能影响

航空动力学报 2017年第2期32卷 330-336页

作者：刘立静李志强北京航空航天大学能源与动力工程学院航空发动机气动热力国家级重点实验室北京100191

基于某药柱式水冲压发动机,建立粉末式水冲压发动机模型.利用Fluent软件模拟研究旋流流动对水冲压发动机流动与燃烧反应性能的影响.选择k-ε双方程模型作为湍流模型,有限速率/涡耗散模型作为燃烧模型,基于密度隐式耦合求解进行计算.结... 详细信息

基于某药柱式水冲压发动机,建立粉末式水冲压发动机模型.利用Fluent软件模拟研究旋流流动对水冲压发动机流动与燃烧反应性能的影响.选择k-ε双方程模型作为湍流模型,有限速率/涡耗散模型作为燃烧模型,基于密度隐式耦合求解进行计算.结果表明:添加旋流叶片并增大旋流角度,燃烧室最高燃烧温度、平均燃烧温度、出口速度和比冲均增大.研究证明添加旋流叶片对水冲压发动机流动与燃烧反应性能有很大改进,且旋流角度越大,效果越明显.

关键词：水冲压发动机旋流流动 Mg/H2O反应燃烧反应旋流角度

失重或模拟失重条件下血管收缩反应变化的研究进展

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航天医学与医学工程 2005年第5期18卷 387-390页

作者：李志利姜世忠航天医学工程研究所北京100094

失重或模拟失重条件下血管收缩功能的改变是立位耐力下降的重要原因。血管功能的实现与血管内的压力、血流状态和血管结构有密切关系,由于血管所处部位不同,其结构和特点也不尽一致。失重或模拟失重时流体静压消失和血液的头向分布,使... 详细信息

失重或模拟失重条件下血管收缩功能的改变是立位耐力下降的重要原因。血管功能的实现与血管内的压力、血流状态和血管结构有密切关系,由于血管所处部位不同,其结构和特点也不尽一致。失重或模拟失重时流体静压消失和血液的头向分布,使身体各部位血管的结构和功能发生着不同的变化,本文就近年来有关这方面的研究作了简要的回顾。

关键词：失重模拟立位耐力血管收缩

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航天血液学研究进展

航天医学与医学工程 2006年第6期19卷 465-467,468页

作者：李志利姜世忠中国航天员科研训练中心北京100094

航天导致身体多个系统发生改变,其中血液系统的变化也非常明显,主要表现为血浆容量和红细胞数量降低等。早期航天血液学研究多限于观察航天中血液学指标的变化,其机理研究则在近几年得到了较大发展。对失重条件下血液学变化也有了新的认... 详细信息

航天导致身体多个系统发生改变,其中血液系统的变化也非常明显,主要表现为血浆容量和红细胞数量降低等。早期航天血液学研究多限于观察航天中血液学指标的变化,其机理研究则在近几年得到了较大发展。对失重条件下血液学变化也有了新的认识,发现了红细胞数量快速下调的机制。本文就有关这方面的重要研究作了简要的回顾。

关键词：失重红细胞促红细胞生成素新生红细胞破坏

免疫球蛋白G糖基化修饰的质谱分析方法及其应用

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质谱学报 2021年第5期42卷 878-896,I0009页

作者：赖治臻周巾煜李智立中国医学科学院基础医学研究所/北京协和医学院基础学院北京100005

IgG是一种参与体液免疫的关键糖蛋白,其通过识别特定抗原发挥清除毒素、激活相应受体和补体、调节机体免疫等功能。IgG糖基化修饰主要为N-糖基化修饰,其恒定区的Asn297上含有1个保守的N-糖基化修饰位点,IgG糖基化修饰状态与其理化性质... 详细信息

IgG是一种参与体液免疫的关键糖蛋白,其通过识别特定抗原发挥清除毒素、激活相应受体和补体、调节机体免疫等功能。IgG糖基化修饰主要为N-糖基化修饰,其恒定区的Asn297上含有1个保守的N-糖基化修饰位点,IgG糖基化修饰状态与其理化性质和生物学功能密切相关。深入研究糖基化修饰对认知免疫分子机制,以及在疾病早期诊断、预后评价和抗体药物研发方面具有重要意义。本文主要在糖链、糖肽和完整蛋白方面综述IgG Fc N-糖基化修饰的质谱分析方法及其应用。

关键词：质谱分析免疫球蛋白G 糖基化修饰

Association between Plasma Leptin Level and Systemic Inflammatory Markers in Patients with Aggressive Periodontitis

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Chinese Medical Journal 2015年第4期128卷 528-532页

作者： Dong Shi Yun-Yu liu Wei li Xin Zhang Xiao-Jun Sun li Xu li Zhang zhi-Bin Chen Huan-Xin Meng Department of Periodontology Peking University School and Hospital of Stomatology Beijing 100081 China

Background：Increasing evidence supports an association between periodontitis and systemic *** is involved both in the energy metabolism and inflammatory processes and is suggested to be a link between periodontal infection and systemic *** present study aimed to evaluate the peripheral leptin concentration in patients with aggressive periodontitis （AgP） and to explore the relationship between leptin and systemic ***：Ninety patients with AgP visiting the Clinic of the Periodontology Department,Peking University School and Hospital of Stomatology between July 2001 and May 2006,and 44 healthy controls （staffand student volunteers in the same institute） were *** levels of leptin and inflammatory cytokines including interleukin （IL）-1β,I L-6,tumor necrosis factor-α （TNF-α） and C-reactive protein （CRP） were measured by enzyme-linked immunosorbent *** and multiple linear regression analysis were performed to analyze the association between plasma leptin level and other ***：Plasma leptin level of AgP group was significantly higher than that of the control group （19.7-4.4 ng/ml vs.7.5 ± 1.3 ng/ml,P ＜ 0.01）.After controlling for age,gender,and body mass index,positive correlation was observed between plasma leptin concentration and log-transformed levels of pro-inflammatory cytokines （IL-1β,IL-6,TNF-α and CRP）,and the partial correlation coefficients ranged from 0.199 to 0.376 （P ＜ 0.05）.Log-transformed IL-1β and I L-6 levels entered the final regression model （standardized β were 0.422 and 0.461 respectively,P ＜ 0.01）.Conclusions：Elevated plasma leptin concentration may be associated with increased systemic levels of inflammatory markers in AgP patients.

关键词： Aggressive Periodontitis Inflammation Mediators Leptin

气相中甲苯离子-分子反应产物的串联质谱研究

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化学学报 1998年第5期56卷 495-499页

作者：李智立刘淑莹中国科学院长春应用化学研究所长春130022

应用碰撞诱导解离技术,研究了甲苯自身化学电离条件下离子-分子反应产物离子m/z 183和184的碰撞诱导解离(CID)反应特性.m/z 183和184离子碎裂反应具有多种过渡态结构,如二苯基甲烷衍生物结构、(艹卓)(钅翁)离子与甲苯形成的共价键结构... 详细信息

应用碰撞诱导解离技术,研究了甲苯自身化学电离条件下离子-分子反应产物离子m/z 183和184的碰撞诱导解离(CID)反应特性.m/z 183和184离子碎裂反应具有多种过渡态结构,如二苯基甲烷衍生物结构、(艹卓)(钅翁)离子与甲苯形成的共价键结构、甲苯自由基离子与甲苯分子形成的π-配合物结构和苄基离子与甲苯形成的π-配合物结构.

关键词：离子-分子反应质谱甲苯二聚体离子 CID

Effect of dopamine and metaraminol on the renal function of patients with septic shock

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Chinese Medical Journal 2007年第8期120卷 680-683页

作者： HOU li-chao li Shu-zhi XIONG li-ze CHEN Shao-yang CHEN Min ZHANG Xi-jing HUO Ting-ting WANG Qiang WANG Ya-li HU Wen-neng Department of Anaesthesiology Xijing Hospital Fourth Military Medical University Xi＇an 710032 China

Background Vasoactive drugs are often necessary for reversing hypotension in patients with severe infection. The standard for evaluating effects of vasoactive drugs should not only be based on the increase of arterial blood pressure, but also on the blood flow perfusion of internal organs. The effects of dopamine and metaraminol on the renal function of the patients with septic shock were investigated retrospectively in this study. Methods Ninety-eight patients with septic shock were divided into three groups according to the highest infusing rate of metaraminol, with the lightest infusing rate of （0.1-0.5, 0.6-1.0, 〉1.0） pg · kg^-1 · min^-1 in group A, B and C respectively. Urine output, mean arterial blood pressure （MAP）, heart rate （HR）, urine output, blood urea nitrogen （BUN）, creatinine （CRE）, urine albumin （U-ALB）, urine β2-microglubulin （Uβ2-MG） and Apache Ⅲ scores were recorded. Results Before antishock therapy, hypotension, tachycardia and oliguria occurred to all the 98 patients with septic shock and CRE, BUN, U-ALB, Uβ2-MG and Apache Ⅲ scoring were abnormal in most cases. With the antishock therapy, MAP, HR, urine output, BUN and CRE in all patients returned gradually to normal （P〈0.05 or 〈0.01 compared to those before antishock therapy）. U-ALB, Uβ2-MG output and Apache Ⅲ scoring also reverted but remained abnormal （P〈0.01 compared to those before antishock therapy）. No statistically significant differences in the changes of these indices with the time existed among the three groups （P〉0.05）.Conclusion Dopamine and metaraminol when applied to the patients with septic shock could effectively maintain the circulatory stability and promote restoration of renal function.

关键词： dopamine metaraminol septic shock renal function

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论传统会计信息生产方式的弊端及其改革

河南师范大学学报（哲学社会科学版） 2008年第4期35卷 99-102页

作者：李立志河南财经学院会计学院河南郑州450002

传统的会计信息生产方式是从企业自身的角度和范围来收集、加工和报告信息的。这种会计信息生产方式不能完全真实地还原和反映社会经济活动的全貌,使得信息加工主体与信息需求主体之间存在着供需错位,很难满足政府经济决策和宏观调控的... 详细信息

传统的会计信息生产方式是从企业自身的角度和范围来收集、加工和报告信息的。这种会计信息生产方式不能完全真实地还原和反映社会经济活动的全貌,使得信息加工主体与信息需求主体之间存在着供需错位,很难满足政府经济决策和宏观调控的需要,也是会计信息失真、造假、不对称的主要根源。面对信息化社会越来越强烈的信息需求,必须改革这种传统会计信息生产方式,即运用先进的计算机网络技术,通过企业与社会经济联系的有关接触点采集企业的经营活动信息,并通过社会化的生产加工进行利用。

关键词：会计信息生产方式弊端改革

Overview of in-situ oxygen production technologies for lunar resources

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International Journal of Minerals,Metallurgy and Materials 2025年第2期32卷 233-255页

作者： Youpeng Xu Sheng Pang liangwei Cong Guoyu Qian Dong Wang Laishi li Yusheng Wu zhi Wang College of Materials Science and Engineering Shenyang University of TechnologyShenyang 110870China CAS Key Laboratory of Green Process and Engineering National Engineering Research Center for Green Recycling of Strategic Metal ResourcesInstitute of Process EngineeringChinese Academy of SciencesBeijing 100190China Innovation Academy for Green Manufacture Chinese Academy of SciencesBeijing 100190China School of Chemical Engineering University of Chinese Academy of SciencesBeijing 100049China

The rich resources and unique environment of the Moon make it an ideal location for human expansion and the utilization of extraterrestrial ***,crucial for supporting human life on the Moon,can be extracted from lunar regolith,which is highly rich in oxygen and contains polymetallic *** oxygen and metal extraction can be achieved using existing metallurgical ***,the ample reserves of water ice on the Moon offer another means for oxygen *** paper offers a detailed overview of the leading technologies for achieving oxygen production on the Moon,drawing from an analysis of lunar resources and environmental *** delves into the principles,processes,advantages,and drawbacks of water-ice electrolysis,two-step oxygen production from lunar regolith,and one-step oxygen production from lunar *** two-step methods involve hydrogen reduction,carbothermal reduction,and hydrometallurgy,while the one-step methods encompass fluorination/chlorination,high-temperature decomposition,molten salt electrolysis,and molten regolith electrolysis(MOE).Following a thorough comparison of raw materials,equipment,technology,and economic viability,MOE is identified as the most promising approach for future in-situ oxygen production on the *** the corrosion characteristics of molten lunar regolith at high temperatures,along with the Moon's low-gravity environment,the development of inexpensive and stable inert anodes and electrolysis devices that can easily collect oxygen is critical for promoting MOE technology on the *** review significantly contributes to our understanding of in-situ oxygen production technologies on the Moon and supports upcoming lunar exploration initiatives.

关键词： lunar resources in-situ oxygen production space metallurgy molten lunar regolith electrolysis