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Radical　Probe　Technique　of　Bragg　Peak　Location　for　Heavy　Ion　Beams　in　Wheat　Seeds

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IMP & HIRFL Annual Report 1995年 70-71页

作者： li Wenjian Wei Zengquan li qiang and xie Hongmei

Ｒａｄｉｃａｌ　Ｐｒｏｂｅ　Ｔｅｃｈｎｉｑｕｅ　ｏｆ　Ｂｒａｇｇ　Ｐｅａｋ　Ｌｏｃａｔｉｏｎ　ｆｏｒ　Ｈｅａｖｙ　Ｉｏｎ　Ｂｅａｍｓ　ｉｎ　Ｗｈｅａｔ　ＳｅｅｄｓＲａｄｉｃａｌＰｒｏｂｅＴｅｃｈｎｉｑｕｅｏｆＢｒａｇ... 详细信息

Ｒａｄｉｃａｌ　Ｐｒｏｂｅ　Ｔｅｃｈｎｉｑｕｅ　ｏｆ　Ｂｒａｇｇ　Ｐｅａｋ　Ｌｏｃａｔｉｏｎ　ｆｏｒ　Ｈｅａｖｙ　Ｉｏｎ　Ｂｅａｍｓ　ｉｎ　Ｗｈｅａｔ　ＳｅｅｄｓＲａｄｉｃａｌＰｒｏｂｅＴｅｃｈｎｉｑｕｅｏｆＢｒａｇｇＰｅａｋＬｏｃａｔｉｏｎｆｏｒＨ...

关键词： Location

基于客票数据的高速铁路旅客出行选择行为研究

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铁道运输与经济 2018年第4期40卷 52-57页

作者：强丽霞中国铁路总公司客运部北京100844

为准确描述高速铁路旅客出行选择特点,为客流分配提供依据,在分析票价、旅行时间、发到时刻等多种因素对旅客出行选择影响的基础上,基于离散选择问题构建旅客出行选择效用函数和旅客出行选择模型,并利用"伯克森-泰尔法"构建回归方程,提... 详细信息

为准确描述高速铁路旅客出行选择特点,为客流分配提供依据,在分析票价、旅行时间、发到时刻等多种因素对旅客出行选择影响的基础上,基于离散选择问题构建旅客出行选择效用函数和旅客出行选择模型,并利用"伯克森-泰尔法"构建回归方程,提出基于客票数据的高速铁路旅客出行回归分析方法与流程。最后,利用2016年3月客票数据对旅客出行行为进行回归分析,标定了部分典型OD的出行选择参数。结果显示,提出的方法具有较高的参数拟合精度。

关键词：高速铁路客运组织出行选择行为客票数据回归分析

Hepatocyte-like cells from directed differentiation of mouse bone marrow cells in vitro

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Acta Pharmacologica Sinica 2005年第4期26卷 469-476页

作者： Xiao-lei SHI~2 Yu-dong QIU~2 qiang li Ting xie~2 Zhang-hua ZHU~2 Lei-lei CHEN~3 Lei li~3 Yi-tao DING~(2,4) 2 Department of Hepatobiliary Surgery 3 Scientific Research Department,Affiliated Drum Tower Hospital,Medical College of Nanjing University,Nanjing 210008,China Department of Hepatobiliary Surgery Affiliated Drum Tower Hospital Medical College of Nanjing University Nanjing China Scientific Research Department Affiliated Drum Tower Hospital Medical College of Nanjing University Nanjing China

Aim:To design the effective directed differentiation medium to differentiate bonemarrow cells into hepatocyte-like ***:Bone marrow cells were cul-tured in the directed differentiation media including fibroblast growth factor-4(FGF-4)and oncostatin M(OSM).Hepatocyte-like cells from directed differentia-tion of bone marrow cells were identified through cell morphology,RNA expres-sions by reverse transcriptase-polymerase chain reaction(RT-PCR),protein ex-pressions by Western blot,and hepatocellular synthesis and metabolism func-tions by albumin EliSA,Periodic acid-Shift staining and urea ***:Some epithelial-like cells or polygonal cells appeared and increased in the courseof the cell directed *** nucleur factor-3[3(HNF-3β),albu-min(ALB),cytokeratin 18(CK18),transthyretin(TTR),glucose-6-phosphate(G-6-Pase),and tyrosine aminotransferase(TAT)mRNA were expressed in the courseof the directed *** directed differentiated cells on d 21 expressedHNF-3β,ALB,and CK18 *** directed differentiated cells producedalbumin and synthesized urea in a time-dependent *** could also syn-thesize ***:Our differentiation media,including FGF-4 andOSM,are effective to differentiate bone marrow cells into hepatocyte-like cells,which could be used for hepatocyte resources for bioartificial liver or hepatocytetransplantation.

关键词： bone marrow cells hepatocytes cell differen tiation stern cells

小纪汗井田地层介质渗透特性及煤层为主含水层成因机制

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煤炭学报 2017年第2期42卷 353-359页

作者：李顺才李强缪协兴陈占清江苏师范大学江苏圣理工工程学院江苏徐州221116 中国矿业大学深部岩土力学与地下工程国家重点实验室江苏徐州221116

以陕北榆横矿区特殊地质背景为基础,通过瞬态渗透试验研究小纪汗煤矿煤系地层的渗透力学特性,基于采集的岩样两端孔隙压差时间序列,通过差分得到渗流速度及其变化率的时间序列,基于最小二乘法计算得到了各层岩样在不同围压下全应力应变... 详细信息

以陕北榆横矿区特殊地质背景为基础,通过瞬态渗透试验研究小纪汗煤矿煤系地层的渗透力学特性,基于采集的岩样两端孔隙压差时间序列,通过差分得到渗流速度及其变化率的时间序列,基于最小二乘法计算得到了各层岩样在不同围压下全应力应变过程中的渗透率、非达西流因子及加速度系数,比较了不同岩层的最大渗透率及最小渗透率。研究表明:1随着压缩应变的增加,煤样应力峰值滞后于渗透率峰值;2应力峰后阶段,煤样非达西流因子及加速度系数先急剧增加后显著下降,两者峰值滞后于应力峰值;3洛河组中粒长石砂岩与2号煤层岩样峰后的最高渗透率显著高于其他岩层;4煤样的渗透率峰后约为1×10-15m2量级,普遍高于一般煤矿煤层的渗透率;5所有岩层中,富县组砂质泥岩的渗透率最低,可视为隔水层。

关键词：榆横矿区小纪汗煤矿煤层为主含水层渗透特性瞬态渗透法

基于模糊综合层次评判法的精密齿轮制造工艺优化优先度分析

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兵工学报 2017年第4期38卷 750-757页

作者：李强谢里阳李海洋张芳敏宋佳昕东北大学现代设计与分析研究所辽宁沈阳110819

传统故障模式影响及危害度分析(FMECA)多应用于产品故障模式风险分析,而未涉及产品制造流程工艺参数优化优先度分析,且其风险优先数(RPN)分析无法对严酷度、发生概率和检测难易程度进行权重分配。因而参照传统FMECA中的RPN分析方法,以... 详细信息

传统故障模式影响及危害度分析(FMECA)多应用于产品故障模式风险分析,而未涉及产品制造流程工艺参数优化优先度分析,且其风险优先数(RPN)分析无法对严酷度、发生概率和检测难易程度进行权重分配。因而参照传统FMECA中的RPN分析方法,以精密齿轮制造工艺流程为研究对象,并考虑齿轮制造当前工艺水平和工艺改进成本等因素,提出优化优先数分析法从而代替RPN分析法,并结合层次分析法-模糊综合评判的方法对齿轮制造流程的各个工艺参数进行优化优先等级评判并排序。最终根据评判结果,提出对重要工艺参数改进的方案,从而提升精密齿轮产品的可靠性和保障性水平。

关键词：机械制造工艺与设备故障模式影响及危害度分析风险优先数工艺参数齿轮制造流程层次分析法-模糊综合评判

准连续激光二极管抽运的Yb∶YAG微晶片激光器

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中国激光 2003年第2期30卷 97-100页

作者：吴海生闫平巩马理柳强李晨谢韬清华大学精密仪器系数字光电与激光技术实验室北京100084

采用峰值功率 1W的国产InGaAs激光二极管作抽运源 ,在室温下实现了光束质量因子M2 <1 4的基横模长脉冲激光振荡。当LD输入电流为 2 15A时 ,使用掺杂浓度为 10at %的Yb∶YAG ,获得了平均功率 1 6 4mW ,单脉冲能量为 16 4 μJ的 1 0 4 ... 详细信息

采用峰值功率 1W的国产InGaAs激光二极管作抽运源 ,在室温下实现了光束质量因子M2 <1 4的基横模长脉冲激光振荡。当LD输入电流为 2 15A时 ,使用掺杂浓度为 10at %的Yb∶YAG ,获得了平均功率 1 6 4mW ,单脉冲能量为 16 4 μJ的 1 0 4 9μm激光输出。同时对准三能级结构激光弛豫振荡过程和准连续 (QCW)输出脉冲宽度进行了理论分析 ,得到了跟实验相符的结果。

关键词：激光技术 Yb:YAG晶体激光二极管抽运光束质量驰豫振荡

Investigation of bubbles escape behavior from low basicity mold flux for high-Mn high-Al steels using 3D X-ray microscope

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International Journal of Minerals,Metallurgy and Materials 2025年第1期32卷 102-110页

作者： qiang liu Xiang li Shen Du Ming Gao Yanbin Yin Jiongming Zhang State Key Laboratory of Advanced Metallurgy University of Science and Technology BeijingBeijing 100083China

During the continuous casting process of high-Mn high-Al steels,various types of gases such as Ar need to escape through the top of the *** which,the behavior of bubbles traversing the liquid slag serves as a restrictive link,closely associated with viscosity and the thickness of liquid *** contrast to two-dimensional surface observation,three-dimensional(3D)analysis method can offer a more intuitive,accurate,and comprehensive ***,this study employs a 3D X-ray microscope(3D-XRM)to obtained spatial distribution and 3D morphological characteristics of residual bubbles in mold flux under different basicity of liquid slag,different temperatures,and different holding *** results indicate that as basicity of slag increases from 0.52 to 1.03,temperature increases from 1423 to 1573 K,the viscosity of slag decreases,the floating rate of bubbles *** addition,when holding time increases from 10 to 30 s,the bubbles floating distance increases,and the volume fraction and average equivalent sphere diameter of the bubbles solidified in the mold flux gradually *** one word,increasing the basicity,temperature,and holding time leading to an increase in the removal rate of bubbles especially for the *** findings of bubbles escape behavior provide valuable insights into optimizing low basicity mold flux for high-Mn high-Al steels.

关键词： mold flux low basicity bubbles three-dimensional X-ray microscope viscosity

Effects of the extrusion parameters on microstructure,texture and room temperature mechanical properties of extruded Mg-2.49Nd-1.82Gd-0.2Zn-0.2Zr alloy

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International Journal of Minerals,Metallurgy and Materials 2025年第1期32卷 136-146页

作者： Chenjin Zhang Guangyu Yang Lei Xiao Zhiyong Kan Jing Guo qiang li Wanqi Jie State Key Laboratory of Solidification Processing Northwestern Polytechnical UniversityXi’an 710072China College of Materials Science and Engineering Fuzhou UniversityFuzhou 350108China College of Chemistry and Environmental Science Qujing Normal UniversityQujing 655011China

Microstructure,texture,and mechanical properties of the extruded Mg-2.49Nd-1.82Gd-0.2Zn-0.2Zr alloy were investigated at different extrusion temperatures(260 and 320℃),extrusion ratios(10:1,15:1,and 30:1),and extrusion speeds(3 and 6 mm/s).The experimental results exhibited that the grain sizes after extrusion were much finer than that of the homogenized alloy,and the second phase showed streamline distribution along the extrusion direction(ED).With extrusion temperature increased from 260 to 320℃,the microstructure,texture,and mechanical properties of alloys changed *** dynamic recrystallization(DRX)degree and grain sizes enhanced as the extrusion ratio increased from 10:1 to 30:1,and the strength gradually decreased but elongation(EL)*** the extrusion speed increased from 3 to 6 mm/s,the grain sizes and DRX degree increased significantly,and the samples presented the typical-rare-earth(RE)*** alloy extruded at 260℃ with extrusion ratio of 10:1 and extrusion speed of 3 mm/s showed the tensile yield strength(TYS)of 213 MPa and EL of 30.6%.After quantitatively analyzing the contribution of strengthening mechanisms,it was found that the grain boundary strengthening and dislocation strengthening played major roles among strengthening *** results provide some guidelines for enlarging the industrial application of extruded Mg-RE alloy.

关键词： Mg-rare earth alloys extrusion temperature extrusion ratio extrusion speed strengthening mechanisms

Magnetron sputtered nickel oxide with suppressed interfacial defect states for efficient inverted perovskite solar cells

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Journal of Energy Chemistry 2025年第1期100卷 348-355页

作者： Guoqiang Ma Qin Tan Zhaoning li Jingwei Xiu Jiafeng Wang Tianle Cheng Dong He qiang Sun Xuhang Ma Francesco Lamberti Zhubing He Department of Materials Science and Engineering Institute of Innovative Materials (I2M) Shenzhen Key Laboratory of Full Spectral Solar Electricity Generation (FSSEG)Southern University of Science and Technology (SUSTech) Core Research Facilities Southern University of Science and Technology Department of Chemical Sciences Department of Industrial Engineering University of Padova

Widely used spin-coated nickle oxide （NiOx） based perovskite solar cells often suffer from severe interfacial reactions between the NiOxand adjacent perovskite layers due to surface defect states,which inherently impair device performance in a long-term view,even with surface molecule *** this study,we developed high-quality magnetron-sputtered NiOxthin films through detailed process optimization,and compared systematically sputtered and spin-coated NiOxthin film surfaces from materials to *** sputtered NiOxfilms exhibit improved crystallinity,smoother surfaces,and significantly reduced Ni3+or Ni vacancies compared to their spin-coated ***,the interface between the perovskite and sputtered NiOxfilm shows a substantially reduced density of defect *** solar cells （PSCs） fabricated with our optimally sputtered NiOxfilms achieved a high power conversion efficiency （PCE） of up to 19.93%and demonstrated enhanced stability,maintaining 86.2% efficiency during 500 h of maximum power point tracking under one standard sun ***,with the surface modification using (4-(2,7-dibromo-9,9-dimethylacridin-10（9H）-yl)butyl)p hosphonic acid （DMAcPA）,the device PCE was further promoted to 23.07%,which is the highest value reported for sputtered NiOxbased PSCs so far.

关键词： Nickle oxide Magnetron sputter Defect Stability Perovskite solar cell