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EAST托卡马克早期H模实验边界局域模特征的统计分析

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东华大学学报（自然科学版） 2024年第2期50卷 153-159页

作者：刘程鸿林新丁楠丁根凡段莫疑杨清泉钟方川王福琼东华大学理学院上海中科院合肥物质科学研究院等离子体物理研究所安徽合肥

为分析EAST托卡马克早期(2010—2014年)高约束运行模式(H模)中边界局域模(ELM)与哪些参数具有强相关性,在验证有效性的基础上,采用主打击点处Dα辐射的相对涨落来定量表征边界局域模幅度,建立EAST托卡马克早期H模下ELM特征数据库。统计... 详细信息

为分析EAST托卡马克早期(2010—2014年)高约束运行模式(H模)中边界局域模(ELM)与哪些参数具有强相关性,在验证有效性的基础上,采用主打击点处Dα辐射的相对涨落来定量表征边界局域模幅度,建立EAST托卡马克早期H模下ELM特征数据库。统计分析表明,ELM频率随边界安全因子的增大而减小,2010年type-ⅢELM的频率随总加热功率的增大而增大。这与其他装置或2015年以后EAST装置上得到的结果不一致,部分原因是碳杂质水平的变化。碳杂质水平是影响EAST托卡马克早期H模实验中ELM行为的重要因素之一。

关键词： EAST托卡马克边界局域模统计分析碳杂质

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基于用户画像及多车协同的环岛车辆换道策略

计算机仿真 2024年第2期41卷 151-156,186页

作者：曹栋发胡创业丁男新疆师范大学计算机科学技术学院新疆乌鲁木齐830054 大连理工大学工业装备智能控制与优化教育部重点实验室辽宁大连116024

基于智能网联汽车车-路-环境的协同策略已成为一种解决智能交通领域问题的有效方案。因此通过结合交通环岛的行车特点,提出了一种基于车辆用户画像的交通环岛换道策略。首先为了解决交通环岛中智能网联汽车多源异构数据的混杂问题,定义... 详细信息

基于智能网联汽车车-路-环境的协同策略已成为一种解决智能交通领域问题的有效方案。因此通过结合交通环岛的行车特点,提出了一种基于车辆用户画像的交通环岛换道策略。首先为了解决交通环岛中智能网联汽车多源异构数据的混杂问题,定义了车辆用户画像,对智能网联汽车多维数据进行表征。其次,基于随机森林算法对车辆用户画像中标签的权重进行实时更新。再次,根据车辆用户画像及动态权重设计收益函数针对环岛出口位置的内道车辆进行换道决策,实现了决策的场景自适应。最后,利用SUMO对本算法在交通拥堵、正常、稀疏等三种场景中进行仿真测试。实验结果表明本算法使得车辆在交通环岛的通行效率和舒适度均得到有效提升,以此验证了车辆用户画像对于优化决策的场景自适应效果的作用。

关键词：智能交通车辆用户画像随机森林算法环岛动态权重

Fracture morphologies of a hot stamped steel and comparisons with several sheet metals

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Journal of Iron and Steel Research International 2017年第6期24卷 634-640页

作者： Shu-lin Tan Kun Yang Ya-nan ding Xian-hong Han Department of Plasticity Technology Shanghai Jiao Tong University Shanghai 200030 China Institute of Chemical Material China Academy of Engineering Physics Mianyang 621900 Sichuan China Department of Civil and Environmental Engineering Northwestern University Evanston 60208 Illinois USA

Hot stamping has been widely used in car industry to produce safety components. Most existing re- searches focused on the stamping and quenching process, but less on the mechanical properties of stamped parts. The fracture behaviors of hot stamped boron steel B1500HS have been studied, and other four commonly used sheet metals with different strengths, including Q235, TRIP780, QP980 and MS1300, were also introduced for comparison. Both uniaxial tests and mechanical trimming tests were performed, and the fracture surfaces under different stress states were observed and discussed. The SEM observations showed that the fracture models are closely related to the stress states, i. e., the tensile surfaces have ductile rupture characters while the trimming surfaces have brittle rupture characters. Compared with other steels, the quenched boron steel has smaller dimple size accompa- nied by shear planes in the tensile surface, and has smaller burnish zone in the trimming surface, and its cutting surface with ＇S＇ like shape is also very different with others. Furthermore, two fitted em pirical models were derived to describe the quantitative correlations between the average dimple diam- eter and the steel strength and between the percentage of burnish zone and the steel strength.

关键词： Hot stamped steelFracture morphologyTensile testMechanical trimming testSteel comparison

Variation of physical properties across the green valley for local galaxies

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Research in Astronomy and Astrophysics 2019年第2期19卷 133-142页

作者： Xue Ge Qiu-Sheng Gu Yong-Yun Chen nan ding School of Astronomy and Space Science Nanjing University Key Laboratory of Modern Astronomy and Astrophysics Nanjing University Collaborative Innovation Center of Modern Astronomy and Space Exploration

We selected a sample of nearby galaxies from the Sloan Digital Sky Survey Data Release 7(SDSS DR7) to investigate the variation of physical properties from the blue cloud to green valley to red *** sample is limited to a narrow range in the color-stellar mass diagram. After splitting green valley galaxies into two parts—a bluer green valley(green 1) and a redder one(green 2) and three stellar mass bins,we investigate the variation of physical properties across the green valley region. Our main results are as follows:(i) The percentages of pure bulge and bulge-dominated/elliptical galaxies increase gradually from blue cloud to red sequence while the percentages of pure disk and disk-dominated/spiral galaxies decrease gradually in all stellar mass bins and different environments.(ii) With the analysis of morphological and structural parameters(e.g., concentration(C) and the stellar mass surface density within the central 1 kpc(Σ1)), red galaxies show more luminous and compact cores than both green valley and blue galaxies, while blue galaxies show the opposite behavior in all stellar mass bins.(iii) A strong negative(positive) relationship between bulge-to-total light ratio(B/T) and specific star formation rate(sSFR)(D_(4000)) is found from blue to red galaxies. Our results indicate that the growth in bulge plays an important role when the galaxies change from the blue cloud, to the green valley and to the red sequence.

关键词： galaxies:structure galaxies:star formation galaxies:bulges

基于ZnCo_(2)O_(4)/g-C_(3)N_(4)的光电化学传感对双酚A的灵敏检测

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广州化工 2024年第13期52卷 68-72,78页

作者：陈鹏丁南茜关金玉张妹湖南农业大学化学与材料科学学院湖南长沙410128

本实验采用溶剂热法制备ZnCo_(2)O_(4)/g-C_(3)N_(4),并将其用于双酚A的灵敏检测。利用扫描电子显微镜观察ZnCo_(2)O_(4)/g-C_(3)N_(4)的形貌特征,利用X-射线单晶衍射仪探究其的晶型结构,利用紫外可见漫反射光谱与莫特肖特基曲线探究其... 详细信息

本实验采用溶剂热法制备ZnCo_(2)O_(4)/g-C_(3)N_(4),并将其用于双酚A的灵敏检测。利用扫描电子显微镜观察ZnCo_(2)O_(4)/g-C_(3)N_(4)的形貌特征,利用X-射线单晶衍射仪探究其的晶型结构,利用紫外可见漫反射光谱与莫特肖特基曲线探究其带隙值及能带结构,用循环伏安法以及交流阻抗法对制备的电极进行了电化学表征。研究表明实验的最佳电压为-0.7 V,利用ZnCo_(2)O_(4)/g-C_(3)N_(4)构建的光电化学传感器检测双酚A,其线性范围为25.0~700.0 ng/L,最低检测限为16.6 ng/L,利用所制备的光电化学传感检测实际样品,回收率在93.0%~97.8%之间,相对标准偏差低于5%。

关键词：光电化学传感双酚A ZnCo_(2)O_(4)/g-C_(3)N_(4)

带骨膜髂骨移植与骨软骨移植治疗距骨骨软骨损伤的临床疗效分析

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中国骨与关节杂志 2024年第9期13卷 686-691页

作者：丁楠鹿军徐军奎樊晓晨西安市红会医院中医康复科陕西省710000

目的探讨距骨骨软骨损伤经自体骨软骨移植与带骨膜髂骨移植治疗后,其临床效果以及影像学表现的差异。方法回顾分析我院2017年5月至2020年10月距骨骨软骨损伤的患者20例,带骨膜髂骨移植组:男5例,女3例;年龄27~72岁,平均(48.12±14.95)岁... 详细信息

目的探讨距骨骨软骨损伤经自体骨软骨移植与带骨膜髂骨移植治疗后,其临床效果以及影像学表现的差异。方法回顾分析我院2017年5月至2020年10月距骨骨软骨损伤的患者20例,带骨膜髂骨移植组:男5例,女3例;年龄27~72岁,平均(48.12±14.95)岁;根据9分区法分组,其中内侧6例,外侧2例。骨软骨移植组:男8例,女4例,年龄17~77岁,平均(41.75±17.87)岁;内侧11例,外侧1例。术前和术后采用美国骨科足踝协会踝-后足评分(American Orthopaedic Foot and Ankle Society,AOFAS)、视觉模拟评分(visual analogue scale,VAS)以及生活质量评分(the MOS 36-item short form health survey,SF-36)进行评定。结果两组患者术前AOFAS、VAS评分以及SF-36评分比较差异均无统计学意义(P>0.05)。两组患者术后AOFAS、VAS评分以及SF-36评分均较术前有所改善,差异有统计学意义(P0.05),带骨膜髂骨移植组VAS评分(1.37±0.51)低于骨软骨移植组(2.08±0.97),差异有统计学意义(P<0.05)。结论带骨膜髂骨移植与骨软骨移植均可有效缓解距骨骨软骨损伤患者踝关节疼痛及改善踝关节功能,带骨膜髂骨移植患者术后疼痛改善更明显。

关键词：距骨软骨创伤和损伤移植,自体骨膜

Low-Level Wind Shear Characteristics and Lidar-Based Alerting at Lanzhou Zhongchuan International Airport,China

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Journal of Meteorological Research 2020年第3期34卷 633-645页

作者： Lanqian LI Aimei SHAO Kaijun ZHANG nan ding Pak-Wai CHAN Key Laboratory for Semi-Arid Climate Change of the Ministry of Education College of Atmospheric SciencesLanzhou UniversityLanzhou 730000 Gansu Sub-Bureau of Northwest Air Traffic Management Bureau of Civil Aviation of China Lanzhou 730087 Hong Kong Observatory KowloonHong Kong 999077

Lanzhou Zhongchuan International Airport[International Civil Aviation Organization(ICAO)code ZLLL]is located in a wind shear prone area in China,where most low-level wind shear events occur in dry weather *** analyzed temporal distribution and synoptic circulation background for 18 dry wind shear events reported by pilots at ZLLL by using the NCEP final(FNL)operational global analysis data,and then proposed a lidar-based regional divergence algorithm(RDA)to determine wind shear intensity and ***-level wind shear at ZLLL usually occurs in the afternoon and evening in dry *** wind shear events occur in an unstable atmosphere over ZLLL,with changes in wind speed or direction generally found at 700 hPa and 10-m *** on synoptic circulations at 700 hPa,wind shear events could be classified as strong northerly,convergence,southerly,and weak wind *** proposed RDA successfully identified low-level wind shear except one southerly case,achieving94%alerting rate compared with 82%for the operational system at ZLLL and 88%for the ramp detection algorithm(widely used in some operational alert systems)based on the same *** RDA-unidentified southerly case occurred in a near neutral atmosphere,and wind speed change could not be captured by the Doppler lidar.

关键词： low-level wind shear synoptic situations alerting algorithm Doppler lidar

银杏叶及其提取物中33种禁用农药残留检测分析及风险评估

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中国现代应用药学 2024年第4期41卷 476-488页

作者：刘丹丹印晓红黄婷丁楠王玉田王芳芳吴萍姚建标浙江康恩贝制药股份有限公司杭州310052 浙江省中药制药技术重点实验室杭州310052

目的建立银杏叶及其提取物中33种禁用农药残留的分析方法,并开展风险评估研究。方法采用液相色谱-串联质谱法及气相色谱-串联质谱法对136批银杏叶及58批银杏叶提取物进行检测,采用点评估方式计算样品中农药残留的急性和慢性摄入风险,采... 详细信息

目的建立银杏叶及其提取物中33种禁用农药残留的分析方法,并开展风险评估研究。方法采用液相色谱-串联质谱法及气相色谱-串联质谱法对136批银杏叶及58批银杏叶提取物进行检测,采用点评估方式计算样品中农药残留的急性和慢性摄入风险,采用英国兽药残留风险排序矩阵计算各农药的风险得分。结果136批银杏叶中共检出6种禁用农药,总检出率为35.29%,农药检出量为0.002~0.210 mg·kg^(-1);检出农药的慢性膳食摄入风险为0.018%~0.620%,急性膳食摄入风险为0.0001%~0.0140%,表明银杏叶中农药的膳食暴露风险处于较低水平。58批银杏叶提取物中共检出2种禁用农药,检出率为55.17%,农药检出量为0.002~1.788 mg·kg^(-1);检出农药的慢性膳食摄入风险为0.003%~0.143%,急性膳食摄入风险为0.0024%,其膳食暴露风险也处于较低水平。风险排序结果表明,银杏叶中甲拌磷风险最高,应在生产和安全监管中重点关注。结论该方法准确,重复性好,可用于银杏叶及其提取物中33种禁用农药的检测。测定结果显示,银杏叶及其提取物中禁用农药残留量极低,无重大健康风险。

关键词：银杏叶银杏叶提取物禁用农药残留风险评估风险排序

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Abnormal infrared effects of nanometer scale thin film material of PtPd alloy in CO adsorption

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Chinese Science Bulletin 2001年第17期46卷 1439-1442页

作者： Zhi Chen Shigang Sun nan ding Zhiyou Zhou Xiamen Univ Dept Chem State Key Lab Phys Chem Solid Surfaces Xiamen 361005 Peoples R China

nanometer scale thin film material of PtPd alloy supported on glassy carbon (nm-PtPd/GC) was prepared by the electrochemical codeposition method under cyclic voltammetric conditions. STM patterns demonstrated that the prepared thin films are composed of layered crystallites in elliptic form. Electrochemical in situ FTIRS studies explored the abnormal infrared effects (AIREs) of nm-PtPd/GC for CO adsorption, which are (i) the remarkable enhancement of IR absorption, (ii) the inversion of COad band direction, and (iii) notable increase in the full width at half maximum (FWHM) of COad bands. The results demonstrated also that the enhancement factor of IR absorption varies with the thickness of PtPd alloy film and has reached a maximum value of 38.3 under the experimental conditions.

关键词： nm-PtPd/GC STM in situ FTIRS AIREs.