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Journal of Materials Science & Technology 2015年第5期31卷 504-511页

作者： Li-na Zhang Ruiling Jia Dan Li Wei Zhang Feng Guo School of Materials Science and Engineering Inner Mongolia University of Technology State Key Laboratory for Corrosion and Protection Institute of Metal ResearchChinese Academy of Sciences

The effect of the rare earth（RE） element Y on the microstructure of AZ91 Mg alloy is investigated.A detailed description of the procedure of identifying the intermetallic phases containing Y in the AZ91 Mg alloy with 0.9 wt%Y addition is *** results shows that there are two different kinds of RE phases in scanning electron microscopy（SEM） *** dispersive spectrum（EDS） analysis shows that one is rich in Y element and the other is rich in Mn *** to the element mapping of electron probe microanalysis（EPMA）.the element Al can be found not only in the β-Mg17Al12phase but also in these two RE phases.X-ray diffraction（XRD） and transmission electron microscopy（TEM） results further confirm one of the two RE phases is AI2Y;the phase of Al10Mn2Y has just been determined by transmission electron microscopy（TEM） instead of XRD probably because it is *** shapes of these two RE intermetallic phases are pretty *** 3D digital microscopy is employed to observe in-situ the effect of the(5 phase and the above two RE intermetallic phases on the corrosion initiation of the *** results show that the corrosion attack of AZ91 Mg alloy without Y addition starts around the eutectic phase β-*** the addition of 0.9 wt%Y,the two kinds of Y-rich intermetallic phases act as cathodic effect and a phase in the adjacent of them was activated and cathodic effect of the β-Mg17Al12phase was inhibited.

关键词： Mg alloy Yttrium Intermetallic phase Corrosion ini

Correlation between ^(29)Si polymerization and cementitious activity of coal gangue

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2009年第9期10卷 1334-1340页

作者： Ji-xiu ZHANG Heng-hu SUN Yin-ming SUN na ZHANG Department of Materials Science and Engineering Tsinghua University Beijing 100084 China

A new method for estimating the degree of [SiO4]4-polymerization of coal gangue is presented. The method uses the relative bridging oxygen number (RBO) based on nuclear magnetic resonance (NMR) techniques. X-ray diffraction (XRD) and 29Si NMR techniques have been used to study phase transitions and silicate polymerization of coal gangue calcined at different temperatures or co-calcined. It has been found that phase transition of clay minerals causes silicate polymerization to change with temperature. In this study, cementing activity and RBO were determined to be inversely related. Generally, activated coal gangue with lower RBO had better cementitious activity.

关键词： Degree of polymerization Relative bridging oxygen number (RBO) Nuclear magnetic resonance (NMR) Coal gangue Cementitious activity

数字创新能力对农业价值链变革的影响——基于两家农业企业的案例研究

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管理案例研究与评论 2024年第2期17卷 242-262页

作者：侯娜张靖怡赵婉争常红郝越刘雯雯北京林业大学经济管理学院北京100083 河北大学经济学院保定071000 北京师范大学经济与工商管理学院北京100875

数字化是产业升级的切入点,农业企业应该借助数字化来优化传统农业,进而完成农业价值链的升级与再造。基于数字创新能力与农业价值链变革理论,选取认养一头牛和丰农控股两家农业企业作为研究对象,通过构建融合数字创新能力与农业价值链... 详细信息

数字化是产业升级的切入点,农业企业应该借助数字化来优化传统农业,进而完成农业价值链的升级与再造。基于数字创新能力与农业价值链变革理论,选取认养一头牛和丰农控股两家农业企业作为研究对象,通过构建融合数字创新能力与农业价值链变革的综合分析框架,深入揭示企业数字创新能力驱动农业价值链变革的机制。研究发现,数字创新能力作为企业的“二阶”能力,会根据不同目标适应性部署,且以活动增值、架构重组、逻辑重塑为表现形式的微观机制能够推动农业价值链变革,实现渐进性和突破性的辩证统一。研究结论可为数字创新能力和价值链变革问题提供新的解释框架和思路,也可为数字化情境下企业推动农业价值链变革实践提供有效路径和理论指导。

关键词：数字创新能力农业价值链变革案例研究

Single t-Quark Productions via Flavor-Changing Processes in Topcolor-Assisted Technicolor Model at Hadron Colliders

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Communications in Theoretical Physics 2008年第1期49卷 193-198页

作者： XU Wen-na WANG Xue-Lei XIAO Zhen-Jun Department of Physics and Institute of Theoretical Physics Nanjing Normal University Nanjing 210097 China College of Physics and Information Engineering Henan Normal University Xinxiang 453007 China

In the framework of topcolor-assisted technicolor （TC2） model, there exist tree-level flavor-changing （FC） couplings, which can result in the loop-level FC coupling tcg. Such tcg coupling can contribute significant clues at the forthcoming Large Hadron Collider （LHC） experiments. In this paper, based on the TC2 model, we study some single t-quark production processes involving tcg coupling at the Tevatron and LHC： pp（pp） → tq （q = u, d, s）, tg. We calculate the cross sections of these processes. The results show that the cross sections at the Tevatron are too small to observe the signal, but at the LHC it can reach a few pb. With the high luminosity, the LHC has considerable capability to find the single t-quark signal produced via some FC processes involving coupling tcg. On the other hand, these processes can also provide some valuable information of the coupling tcg with detailed study of the processes and furthermore provide the reliable evidence to test the TC2 model

关键词： topcolor-assisted technicolor model flavor-changing couplings hadron colliders electroweak symmetry breaking

Revisiting the dichotomy of early-type galaxies

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Research in Astronomy and Astrophysics 2014年第2期14卷 144-158页

作者： Yan-Qin He Cai-na Hao Xiao-Yang Xia University of Chinese Academy of Sciences national Astronomical Observatories Chinese Academy of Sciences Tianjin Astrophysics Center Tianjin Normal University

We study the relationship between isophotal shapes, central light profiles and kinematic properties of early-type galaxies （ETGs） based on a compiled sample of 184 ETGs. These sample galaxies are included in Data Release 8 of the Sloan Digital Sky Survey and have central light profiles and kinematic properties available from the literature, which were compiled from observations by the Hubble Space Telescope and the ATLAS3D integral-field spectrograph, respectively. We find that there is only a weak correlation between the isophotal shape （a4/a） and the central light profile （within 1 kpc） of ETGs. About two-fifths of ＂core＂ galaxies have disky isophotes, and one-third of ＂power-law＂ galaxies are boxy. Our statistical results also show that there are weak correlations between galaxy luminosity and dynamical mass with a4/a, but such correlations are tighter with a central light profile. Moreover, no clear link has been found between the isophotal shape and the Sersic index. Comparisons show that there are similar correlations between a4/a and ellipticity, and between a4/a and specific angular momentum ARo/2 for ＂power-law＂ ETGs, but there are no such correlations for ＂core＂ ETGs. Therefore, we speculate that the bimodal classifications of ETGs are not as simple as previously thought, though we also find that the disky ETGs with highest a4/a are more elongated and fast rotators.

关键词： galaxies: elliptical and lenticular cD -- galaxies: kinematics and dynamics -- galaxies: photometry -- galaxies: structure

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《工艺之美·文化之韵——玉环紫砂》

中国陶瓷 2024年第7期60卷 84-84页

作者：王娜叶玲燕湖州师范学院艺术学院教工第三党支部中国工艺美术协会湖州师范学院艺术学院

关键词：

含未知输入非线性系统的扩展平方根容积卡尔曼滤波算法

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科学技术与工程 2024年第14期24卷 5892-5900页

作者：鹿子豪王娜林崇赵克友董世桂青岛大学自动化学院青岛266071 青岛大学山东省工业控制技术重点实验室青岛266071 青岛大学复杂性科学研究所青岛266071

针对工程实际应用中存在的未知输入会导致经典的非线性滤波器状态估计精度下降甚至滤波发散的问题,提出了一种基于最小方差无偏估计(minimum variance unbiased estimation,MVUE)准则的扩展平方根容积卡尔曼滤波(extended square-root c... 详细信息

针对工程实际应用中存在的未知输入会导致经典的非线性滤波器状态估计精度下降甚至滤波发散的问题,提出了一种基于最小方差无偏估计(minimum variance unbiased estimation,MVUE)准则的扩展平方根容积卡尔曼滤波(extended square-root cubature Kalman filter,ESRCKF)算法。首先,结合上一时刻未知输入估计值对状态一步预测值进行修正,得到含未知输入条件下的状态预测值。其次,设计新息并采用加权最小二乘(weighted least squares,WLS)法获取当前时刻未知输入的无偏估计。最后,通过最小化协方差矩阵的迹,同时采用拉格朗日乘子法和舒尔补引理得到系统状态的最小方差无偏估计。仿真结果表明,相比于现有的非线性滤波算法,ESRCKF算法提高了在处理含未知输入非线性系统时的状态估计精度,并能同时实现系统状态和未知输入的最优估计,验证了该算法的有效性。

关键词：平方根容积卡尔曼滤波最小方差无偏估计加权最小二乘法状态估计未知输入估计

Ruthenium Trichloride Catalyzed Highly Efficient Deoximation of Oximes to the Carbonyl Compounds and Nitriles without Acceptors

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Chinese Journal of Chemistry 2015年第9期33卷 1011-1014页

作者： Yuxiao Liu na Yang Changhu Chu Renhua Liu School of Pharmacy East China University of Science and Technology Shanghai 200237 China

An acceptor-free catalysis protocol for the deoximation of ketoximes and aldoximes using RuCl3 as the catalyst has been developed. Under the optimized conditions, various oximes were converted to ketones and nitriles ... 详细信息

关键词： deoximation ruthenium trichloride hydrolysis acceptor-free

Clinically available Rna profiling tests of prostate tumors： utility and comparison

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Asian Journal of Andrology 2016年第4期18卷 575-579页

作者： Rong na Yishuo Wu Qiang Ding Jianfeng Xu Fudan Institute of UrologY Huashan Hospital Fudan University Shanghai China Department of Urology Huashan Hospital Fudan University Shanghai China Program for Personalized Cancer Care NorthShore University HealthSystem Evanston IL USA.

In the postscreening era, physicians are in need of methods to discriminate aggressive from nonaggressive prostate cancer （PCa） to reduce overdiagnosis and overtreatment. However, studies have shown that prognoses （e.g., progression and mortality） differ even among individuals with similar clinical and pathological characteristics. Existing risk classifiers （TMN grading system, Gleason score, etc.） are not accurately enough to represent the biological features of PCa. Using new genomic technologies, novel biomarkers and classifiers have been developed and shown to add value to clinical or pathological risk factors for predicting aggressive disease. Among them, Rna testing （gene expression analysis） is useful because it can not only reflect genetic variations but also reflect epigenetic regulations. Commercially available Rna profiling tests （Oncotype Dx, Prolaris, and Decipher） have demonstrated strong abilities to discriminate PCa with poor prognosis from less aggressive diseases. For instance, these Rna profiling tests can predict disease progression in active surveillance patients or early recurrence after radical treatments. These tests may offer more dependable methods for PCa prognosis prediction to make more accurate and personal medical decisions.

关键词： precision medicine prostate cancer Rna profiling