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蓝宝石光学曲面柱形宽缎带磁流变抛光仿真分析及实验研究

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表面技术 2024年第4期53卷 140-151页

作者：阎秋生汪涛黄展亮黄蓓潘继生陈缘靓夏江南广东工业大学机电工程学院广州510006

目的针对目前光滑无损伤光学曲面蓝宝石加工成本高、效率低的问题,对加工过程中磁流变抛光缎带进行流体仿真,进而优化抛光轮表面结构。方法设计并提出3种表面结构柱形宽缎带磁流变抛光轮,介绍了磁流变抛光轮加工的基本原理,建立了磁流... 详细信息

目的针对目前光滑无损伤光学曲面蓝宝石加工成本高、效率低的问题,对加工过程中磁流变抛光缎带进行流体仿真,进而优化抛光轮表面结构。方法设计并提出3种表面结构柱形宽缎带磁流变抛光轮,介绍了磁流变抛光轮加工的基本原理,建立了磁流变抛光垫Bingham流体特性加工仿真模型,分析了3种抛光轮表面结构对工件表面磁通密度模、流场流速、流场压力分布的影响。同时对3种抛光轮的抛光效果进行了实验探究,探究了抛光轮表面结构对材料去除率和抛光后表面粗糙度的影响规律。结果仿真结果表明,抛光轮表面槽型结构具有能增强磁通密度模、增大流体流速和流体压力的特性。实验结果表明,螺旋槽抛光轮的抛光效果最好,在螺旋抛光轮作用下,材料去除率为0.22mg/h,抛光后蓝宝石表面粗糙度为1.08nm。最终抛光轮近壁区总压力和速度的乘积结果与抛光轮实验去除率结果具有较好的一致性。结论槽型结构可以提高抛光液在抛光轮表面的固着效果,影响工件表面流场运动状态,增强工件表面受到抛光垫的作用力。相较于光滑和横条槽抛光轮,螺旋槽抛光轮的抛光效率最高,表面粗糙度最低,可有效提高抛光效果。

关键词：抛光缎带蓝宝石 Bingham流体抛光轮槽型结构数值计算流场

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金属钼圆基片平面研磨及其表面创成机理研究

表面技术 2024年第12期53卷 181-192页

作者：阎秋生陈缘靓夏江南雒梓源汪涛广东工业大学机电工程学院广州510006

目的实现金属钼圆基片高效平坦化加工,获得超光滑表面。方法采用游离磨料对钼圆基片进行平面研磨加工,研究磨料种类及研磨盘转速、研磨压力、研磨时间等工艺参数对研磨效果的影响规律,通过材料去除率(MRR)与表面粗糙度(Ra)的建模分析,... 详细信息

目的实现金属钼圆基片高效平坦化加工,获得超光滑表面。方法采用游离磨料对钼圆基片进行平面研磨加工,研究磨料种类及研磨盘转速、研磨压力、研磨时间等工艺参数对研磨效果的影响规律,通过材料去除率(MRR)与表面粗糙度(Ra)的建模分析,对比钼材与高硬脆和高塑性材料,揭示其研磨工艺特性、探究其表面创成机理。结果钼圆基片材料去除快慢和表面形貌受各因素作用的综合影响。CeO_(2)磨料适合钼圆基片的研磨加工,材料去除方式为二体、三体摩擦塑性去除;在研磨过程中,MRR随研磨盘转速、研磨压力的递增而先增大后减小,在研磨盘转速为60 r/min、研磨压力为0.026 MPa条件下MRR达到最大;除磨料因素外,其他工艺因素对表面粗糙度的影响较小;MRR和Ra随加工时间的延长而趋于稳定;使用粒径W1 CeO_(2)磨料在研磨盘转速为60 r/min、研磨压力为0.026 MPa下研磨40 min后,表面粗糙度Ra由46 nm降至9.53 nm,MRR达1.16 mg/min。结论采用游离磨料研磨方法在优化工艺条件下可以有效降低表面粗糙度,获得良好表面。

关键词：钼圆基片研磨工艺参数材料去除率表面粗糙度加工机理

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火星表面上升轨迹映射伪谱凸优化方法

深空探测学报（中英文） 2024年第1期11卷 40-46页

作者：徐源景刘旭彭胜军席涛朱永生肖遥李爽南京航空航天大学航天学院南京211106 西安卫星测控中心西安710699 宇航动力学国家重点实验室西安710043 中国科学院微小卫星创新研究院上海201304 北京空间飞行器总体设计部北京100094

针对火星表面上升轨迹优化问题,提出了映射Chebyshev伪谱凸优化方法。首先采用无损凸化方法对火星表面上升燃耗最优问题进行凸松弛,然后将凸化后的问题在映射Chebyshev-Gauss-Lobatto点处离散,利用重心有理Lagrange插值技术进行插值,最... 详细信息

针对火星表面上升轨迹优化问题,提出了映射Chebyshev伪谱凸优化方法。首先采用无损凸化方法对火星表面上升燃耗最优问题进行凸松弛,然后将凸化后的问题在映射Chebyshev-Gauss-Lobatto点处离散,利用重心有理Lagrange插值技术进行插值,最后使用序列凸优化方法迭代求解,得到数值最优解。仿真对比了本文方法、一般伪谱凸优化方法和经典的序列凸优化方法,证明了本文方法在计算效率方面存在优势,并有效改善了标准Chebyshev微分矩阵的病态特性。

关键词：火星上升 Chebyshev伪谱法凸优化

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制备工艺对格列美脲片溶出行为的影响

中国现代应用药学 2017年第11期34卷 1572-1575页

作者：马莉刘兆迅王文笙陶元景山东达因海洋生物制药股份有限公司山东荣成264300

目的探索不同制备工艺对格列美脲片溶出行为的影响。方法以溶出度及在p H(7.20±0.05)缓冲液中溶出曲线为检测指标,并结合流动性和可压性,考察粉末直接压片、干法制粒压片、湿法制粒压片对格列美脲片溶出行为的影响。结果采用粉末直接... 详细信息

目的探索不同制备工艺对格列美脲片溶出行为的影响。方法以溶出度及在p H(7.20±0.05)缓冲液中溶出曲线为检测指标,并结合流动性和可压性,考察粉末直接压片、干法制粒压片、湿法制粒压片对格列美脲片溶出行为的影响。结果采用粉末直接压片、干法制粒压片、湿法制粒压片工艺制备的格列美脲片溶出行为存在一定差异。结论采用空白辅料湿法制粒,外加原料药混合压片制得格列美脲片与参比制剂溶出行为一致,且产品质量稳定,为格列美脲片一致性评价工作奠定了基础。

关键词：格列美脲片制备工艺溶出度

Implementation methods and economic impacts of national node strategies

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Journal of Geographical Sciences 2017年第3期27卷 348-364页

作者： QI yuanjing LIU tao JIAO Jingjuan School of Soil and Water Conservation Beijing Forestry University Beijing 100083 China Engineering Technology Research Center of Forestry Ecological Engineering Ministry of Education (Beijing Forestry University) Beijing 100083 China Center for Population and Development Studies Renmin University of China Beijing 100872 China Beijing Jiaotong University Beijing 100044 China

Pilot reforms gradually implemented through key nodes have become an important pattern of regional development in China since the policy of reform and opening up was in- troduced in 1978. On the basis of an analysis of the evolution processes and characteristics of regional development policies in post-reform China, this paper develops the concept and analytical framework of national node strategies （NNS）, defined as regional development strategies centered on specific spatial nodes, by addressing their theoretical basis and re- search scope. The regional economic impacts of NNS were explored quantitatively through the examples of the Shenzhen Special Economic Zone, Pudong New Area and Tianjin Binhai New Area in different stages of the reform and opening up. The results indicate that the evo- lution of China＇s regional development policies can be divided into three stages： the explora- tion stage led by Special Economic Zones （SEZs）, the expansion stage dominated by Eco- nomic Development Zones and the optimization stage featuring State-level New Areas and National Comprehensive Reform Pilot Areas. During all the three stages, NNS have played an important demonstrative and leading role and promoted the rapid evolution of China＇s regional development policies from localized to widespread implementation, and the role of the government has also changed accordingly. As an innovative application and development of the growth pole theory in transitional China, NNS have become engines of regional de- velopment as well as important conduits of institutional innovations. NNS and regional de- velopment have achieved a benign coupling and formed a gradated regional development model. Empirical research indicates that NNS are an important method used by the govern- ment to guide and regulate regional economic development, with complex and diverse eco- nomic effects that differ depending on the stage of regional development and the spatial scale of analysis.

关键词： regional development strategy national node strategies growth pole economic impact

Spatial patterns, driving forces, and urbanization effects of China＇s internal migration： County-level analysis based on the 2000 and 2010 censuses

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Journal of Geographical Sciences 2015年第2期25卷 236-256页

作者： LIU tao QI yuanjing CAO Guangzhong LIU Hui Department of Geography The University of Hong Kong HK 999077 China School of Soil and Water Conservation Beijing Forestry University Beijing 100083 China College of Urban and Environmental Sciences Peking University Beijing 100871 China Department of Geography and Resource Management The Chinese University of Hong Kong HK 999077China

China has witnessed unprecedented urbanization over the past decades. The rapid expansion of urban population has been dominantly contributed by the floating population from rural areas, of which the spatiotemporal patterns, driving forces, and multidimensional effects are scrutinized and evaluated in this study by using the latest national censuses conducted in 2000 and 2010. Analysis based on the county-level data comes to conclusions as follows. The spatial pattern of floating population has remained stable over the first decade of the new century. The top 1% cities with the largest floating population received 45.5% of all migrants in China. As the rapid development of mega-city regions, the coastal concentration areas of floating population tended to geographically united as a whole, whereas the spatial distribution of migrants within each region varied significantly. The migrant concentration area in the Yangtze River Delta was the largest and its expansion was also the most salient. However, the floating population has growingly moved into provincial capitals and other big cities in the inland regions and its gravity center has moved northward for around 110 km during the study period. The spatial pattern of floating population has been formed jointly by the state and market forces in transitional China and the impacts of state forces have been surpassed by those of market forces in the country as a whole. The attractiveness of coastal cities and counties to the floating population comes mainly from the nonagricultural employment opportunities and public services, reflecting that long-distance and long-term migrants have moved coastward not only to gain employment but also to enjoy city life. By contrast, in the central and western regions, places with a higher economic development level and at a higher administrative level are more attractive to floating populations, demonstrating that the state remains to play an important role in allocating economic resources and promoting regional development in inland

关键词： floating population migration urbanization urban system megacity region census China

复方碳酸钙泡腾颗粒中维生素D_3含量测定的方法改进

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药学研究 2017年第7期36卷 393-395页

作者：马莉王英新王龙江陶元景山东达因海洋生物制药股份有限公司山东荣成264300

目的建立复方碳酸钙泡腾颗粒中维生素D_3含量检测方法。方法采用Phenomenex Luna-Silica(2)100A色谱柱(4.6 mm×100 mm,3μm),以正己烷-正戊醇(997∶3)为流动相,检测波长254 nm,柱温30℃,流速1.5mL·min^(-1),进样量200μL。结果维生素... 详细信息

目的建立复方碳酸钙泡腾颗粒中维生素D_3含量检测方法。方法采用Phenomenex Luna-Silica(2)100A色谱柱(4.6 mm×100 mm,3μm),以正己烷-正戊醇(997∶3)为流动相,检测波长254 nm,柱温30℃,流速1.5mL·min^(-1),进样量200μL。结果维生素D_3在浓度0.621 5~1.165 4μg·mL^(-1)范围内线性关系良好(r=0.999 5),平均回收率为100.7%(RSD=1.80%,n=9)。结论所用方法简便、准确、专属性强、重复性好,能够检测复方碳酸钙泡腾颗粒中维生素D_3含量。

关键词：复方碳酸钙泡腾颗粒维生素D3 含量测定

Tomato Green Cultivation Technology of Reducing Fertilizer and Pesticide Input and Increasing Fertilizer Efficiency

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Plant Diseases and Pests 2022年第3期13卷 31-34页

作者： Yongxun MAO Chun LI Lanxiang MA yuanjing XU tao WEI Zaozhuang Academy of Agricultural Sciences Zaozhuang 277399China Zaozhuang Agricultural Machinery Technology Extension Center Zaozhuang 277101China

According to the technical approach of green production and yield increase pattern,green,pollution-free,quality and efficiency improvement can be achieved by reducing nitrogen,controlling phosphorus and stabilizing potassium,replenishing sulfur,zinc,iron,manganese and boron from the aspects of controlling fertilizer,drug and water.The main measures include combination use of organic and inorganic fertilizer,effective control of the amount of nitrogen and phosphate fertilizer,reduction of the application amount of chemical fertilizers and pesticides,and rational crop rotation to reduce the occurrence of diseases and insect pests,which can improve the yield and quality of tomato.

关键词： Tomato Intensive technology Pollution-free Quality and efficiency improvement

Roles of integrin β3 cytoplasmic tail in bidirectional signal transduction in a trans-dominant inhibition model

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Frontiers of Medicine 2016年第3期10卷 311-319页

作者： Jiansong Huang Yulan Zhou Xiaoyu Su yuanjing Lyu Lanlan tao Xiaofeng Shi Ping Liu Zhangbiao Long Zheng Ruan Bing Xiao Wenda Xi Quansheng Zhou Jianhua Mao Xiaodong Xi State Key Laboratory of Medical Genomics Shanghai Institute of Hematology Collaborative Innovation Center of Hematology Ruijin Hospital Affiliated to Shanghai Jiao Tong University School of Medicine Shanghai 200025 China Institute of Hematology The First Affiliated Hospital School of Medicine Zhejiang University Hangzhou 310003 China Department of Hematology The First Affiliated Hospital of Nanchang University Nanchang 330006 China Department of Hematology Affiliated Hospital of Jiangsu University Zhenjiang 212001 China Department of Pediatrics Renji Hospital Shanghai Jiao Tong University School of Medicine Shanghai 200001 China Department of Hematology Peking Union Medical College Hospital Chinese Academy of Medical Sciences & Peking Union Medical College Beijing 100073 China Shanghai Institute of Hypertension Ruijin Hospital Affiliated to Shanghai Jiao Tong University School of Medicine Shanghai 200025 China Cyrus Tang Hematology Center Jiangsu Institute of Hematology 2011 Collaborative Innovation Center of Hematology Soochow University Suzhou 215123 China Sino-French Research Centre for Life Sciences and Genomics Ruijin Hospital Affiliated to Shanghai Jiao Tong University School of Medicine Shanghai 200025 China

We evaluated the roles of calpain cleavage-related mutations of the integrin β3 cytoplasmic tail in integrin αIIbβ3 bidirectional signaling using a trans-dominant inhibition model. Chimeric Tac-β3 proteins （i.e., Tac-β3, Tac-β3△741, Tac-β3△747, Tac-β3△754, Tac-β3△759, and Tac-β3ANITY） consisting of the extracellular and transmembrane domains of human IL-2 receptor （Tac） and the human integrin β3 cytoplasmic domain were stably expressed in the 123 CHO cells harboring human glycoprotein Ib-IX and wild-type integrin uIIbβ3. The different cells were assayed for stable adhesion and spreading on immobilized fibrinogen, and for binding soluble fibrinogen representing outside-in and inside-out signaling events, respectively. The chimeric protein Tac-β3 inhibited, and Tac-β3△NITY partially attenuated stable adhesion and spreading. Tac-β3, Tac-β3△759, Tac-β3ANITY, and Tac-β3△754, but not Tac-β3△747 or Tac-β3△741, impaired the soluble fibrinogen binding. Results indicated that the bidirectional signaling was significantly inhibited by Tac-β3△ and Tac-β3ANITY, albeit to a much lesser extent. Moreover, only inside-out signaling was impaired in the 123/Tac-β3△759 and 123/Tac-β3△754 cells in contrast to an intact bidirectional signaling in the 123/Tac-β3△747 and 123/Tac-β3△741 cells. In conclusion, the calpain cleavage of integrin β3 resulted in the regulatory effects on signaling by interrupting its interaction with cytoplasmic proteins rather than altering its conformation, and may thus regulate platelet function.

关键词： integrin β3 signal transduction tmns-dominant inhibition model