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Adaptive Penalized Weighted Least Absolute Deviations Estimation for the Accelerated Failure Time Model

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Acta Mathematica Sinica,English Series 2020年第7期36卷 812-828页

作者： Ming qiu wang Yuan Shan WU Qing Long YANG School of Statistics Qufu Normal UniversityQufu 273165P.R.China School of Statistics and Mathematics Zhongnan University of Economics and LawWuhan 430073P.R.China

The accelerated failure time model always offers a valuable complement to the traditional Cox proportional hazards model due to its direct and meaningful *** propose a variable selection method in the context of the accelerated failure time model for survival data,which can simultaneously complete variable selection and parameter ***,the proposed method can deal with the potential outliers in survival times as well as heteroscedastic model errors,which are frequently encountered in ***,utilizing the general nonconvex penalty,we propose the adaptive penalized weighted least absolute deviation estimator for the accelerated failure time *** some regularity conditions,we show that the proposed method yields consistent estimator and possesses the oracle *** addition,we propose a new algorithm to compute the estimate in the high dimensional settings,and evaluate the practical utility of the proposed method through extensive simulation studies and two real examples.

关键词： estimation. property. estimator

Comparison of microstructure and heat treatment distortion of gear steels with and without Nb addition

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Journal of Iron and Steel Research International 2021年第4期28卷 488-495页

作者： Guo-qiang Zhang Xiao-fei He Qian-zhen Zhang Wen-jun wang Mao-qiu wang Institute of Special Steel Central Iron and Steel Research InstituteBeijing 100081China NGC Group Nanjing 211102JiangsuChina Technical Center CITIC Metal GroupBeijing 100027China

In order to research the effect of microalloying Nb,the microstructure and heat treatment distortion of case carburizing steels with and without Nb addition are *** show that a uniform and fine prior austenite grain size was obtained for the steel with the addition of 0.03 wt.%Nb even after being carburized at 980℃for 37 h,resulting in a very deep hardened layer of about 4 *** is an effective microalloying element to hinder austenite grain growth of gears during high-temperature *** calculation and experimental observation of NbC precipitates indicate that fine NbC precipitates have not evidently dissolved at 980℃,and thus they can act as grain refiners due to pinning *** treatment distortion of Nb-added steel is much lower than that of the steel without Nb *** may be contributed to its fine and uniform grain size,which presumably influences stress during martensitic transformation.

关键词： Case hardening steel High-temperature carburizing Grain size Heat treatment distortion Microstructure

An Analysis of China's Current Situation of Deindustrialization

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当代财经 2013年第S1期 3-11页

作者： wang qiu-shi wang Yi-xin Jiangxi University of Finance and Economics

Since the reform and opening up,China has undergone a rapid economic development;by the end of 2010,China has overtaken Japan to become the world’s second largest economy only after the *** China’s total economic output increases,economic restructuring and economic policy-making become particularly *** an inevitable economic phenomenon when the economic development reaches a certain stage,deindustrialization should be analyzed *** article conducts an analysis of China’s present situation of deindustrialization from two levels:gross deindustrialization and regional *** the re-classification of the regional deindustrialization,we tries to explore the mechanism behind both the positive and negative deindustrialization,as well as the impact on the economic development,so as to provide a theoretical basis for the formulation of our industrial policy and decision-making of economic development.

关键词： gross deindustrialization regional deindustrialization industrial restructuring

Synthesis of Long Chain Fatty Acids Acylated Coumarin Glycoside Esters with Lipase as Catalyst

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Chemical Research in Chinese Universities 2015年第4期31卷 534-538页

作者： LIU Duo CAI Shuanglian LUAN Fangjian wang qiu'an State Key Laboratory of Chemo/Biosensing and Chemometrics College of Chemistry and Chemical Engineering Hunan University Changsha 410082 P. R. China

A series of novel coumarin glycoside esters（1-9） was synthesized through the acylation reaction of 4-methylcoumarin-7-O-β-D-glucoside（11） with different long chain fatty acids catalyzed by lipase in organic medium. The acylation occurred regioselectively at the 6＇-OH of glycosyl moiety. The enzymatic synthesis was optimized to achieve 54%-70% yield using immobilized lipase（Novozym 435, 10 mg/mL） as catalyst and acetone and pyri- dine（9：1, volume ratio, water content〈1%） as solvent with an acyl donor/coumarin glycoside molar ratio of 10：1 at a temperature of 40--50 ℃ for 96 h. All the synthesized compounds were confirmed.

关键词： Coumarin glycoside Lipase-catalyzed acylation Long chain fatty acid Regioselective acylation

Hydrogen Absorption and Desorption during Heat Treatment of AISI 4140 Steel

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Journal of Iron and Steel Research International 2014年第10期21卷 951-955页

作者： Ming-da ZHANG Mao-qiu wang Han DONG National Engineering Research Center of Advanced Steel Technology Central Iron and Steel Research Institute School of Materials Science and Engineering Tsinghua University

Hydrogen plays an important role in the formation of quench cracks of structural steels. To clarify hydrogen ab- sorption and desorption during heat treatment of AISI 4140 steel, thermal desorption spectrometry （TDS） analysis was carried out for the specimens in the as-rolled, as quenched, and quenched and tempered conditions. Results show that hydrogen content increased from 0. 127 ×10 6 in the as-rolled specimen to 0. 316 × 10-6 in the as-oil-quenched specimen. After tempering at 200 ℃, the hydrogen content in the oil-quenched specimen decreased to 0. 155 × 10-6 , and the peak temperature of hydrogen desorption increased from 200 to 360 ℃. From the dependence of hydrogen content in the as-quenched specimens on austenitizing time, it can be deduced that hydrogen absorption occurs during austenitizing. The simulation of hydrogen absorption contributes to a better understanding on the distribution of hy- drogen during the heat treatment in structural steels.

关键词： steel hydrogen absorption heat treatment thermal desorption spectrometry

Effect of solanine on the membrane potential of mitochondria in HepG_2 cells and [Ca^(2+)]i in the cells

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World Journal of Gastroenterology 2006年第21期12卷 3359-3367页

作者： Shi-Yong Gao qiu-Juan wang Yu-Bin Ji Physiology Section Department of Pharmacy China Pharmaceutical University Nanjing 210009 Jiangsu Province China Postdoctoral Research Station The Institute of Materia Medica Harbin University of Commerce Harbin 150076 Heilongjiang Province China

AIM： To observe the effect of solanine on the membrane potential of mitochondria in HepG2 cells and [Ca^2＋]i in the cells, and to uncover the mechanism by which solanine induces ***： HepG2 cells were double stained with AO/EB, and morphological changes of the cells were observed using laser confocal scanning microscopy （LCSM）. HepG2 cells were stained with TMRE, and change in the membrane potential of mitochondria in the cells were observed using LCSM. HepG2 cells were double stained with Fluo-3/AM, and change of [Ca^2＋]i in the cells were observed using LCSM. HepG2 cells were double stained with TMRE and Fluo-3/AM, and both the change in membrane potential of mitochondria and that of [Ca^2＋]i in the cells were observed using ***： Cells in treated groups showed typical signs of apoptosis. Staining with TMRE showed that solanine could lower membrane potential; staining with Fluo-3/AM showed that solanine could increase the concentration of Ca^2＋ in tumor cells; and those of double staining with TMRE and Fluo-3/AM showed that solanine could increase the concentration of Ca^2＋ in the cells at the same time as it lowered the membrane potential of ***： Solanine opens up the PT channels in the membrane by lowering the membrane potential, leading to Ca^2＋ being transported down its concentration gradient, which in turn leads to the rise of the concentration of Ca^2＋ in the cell, turning on the mechanism for apoptosis.

关键词： Solanine Hepatocarcinomatic cell Ca^2+ in the cell Membrane potential Laser confocal scanning microscopy

Impact of and adaptation strategies for sea-level rise on Yangtze River Delta

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Advances in Climate Change Research 2018年第2期9卷 154-160页

作者： wang qiu-Shun PAN Cun-Hong ZHANG Guang-Zhi Zhejiang Institute of Hydraulics and Estuary Hangzhou 310020 China Zhejiang Institute of Marine Planning and Design Hangzhou 310020 China

The Yangtze River Delta characterized by a dense population and a rapidly developing economy is highly vulnerable to sea-level rise. The data from the China Oceanic Information Network and the Zhejiang Provincial Hydrology Bureau are used to analyze sea-level rise. The rate of sea-level rise in the delta was 2.4 mm per year in 1981-2015. The annual sea-level at Daishan, Dinghai, and Dongtou stations in the south wing of the delta were 4.3, 3.1, and 5 mm per year respectively over the same period. The 10-year averaged results at each station also indicate a perceptible trend of sea-level rise. Sea-level rise is contributed to a larger proportion of intensified erosion, ranging from 3% to 14% in the delta. Meanwhile, the 100-year return period of tidal level has decreased to the 50-year rank at Dongtou and Dinghai stations. Moreover, the arrival time of tidal bores at Yanguan is 4 min earlier under sea-level rise of 0.145 m than that of 0 m. The height of tidal bores and the velocities at the surface and bottom layers have an increase under sea-level rise. The maximum increases of high and low tide levels are 0.122 m and 0.016 m while the maximum increases of the velocities at the surface and bottom layers are 0.07 m s^- 1 and 0.05 m s ^-1, respectively. Sea-level rise will bring about the damage of seawall, thus the design standard of constructing seawalls should adopt a higher level to minimize the associated risks in the Yangtze River Delta and its south wing.

关键词： Coastal erosion Sea-level rise Saltwater intrusion Tidal bore Yangtze River Delta Zhejiang province

Synthesis and Fluorescence Properties of Coumarin Glycosides and Triazoylglycosides

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Chemical Research in Chinese Universities 2013年第3期29卷 460-465页

作者： WU Zheng FU Xin-ling YANG Nan wang qiu-an College of Chemistry and Chemical Engineering Hunan University Changsha 410082 P. R. China School of Pharmaceutical Sciences Guangxi Medical University Nanning 530021 P. R. China Department of Basic Medical Changsha Medical University Changsha 410082 P. R. China

Four coumarin glycosides（1-4） and four coumarin triazoylglycosides（5--8） were synthesized by phase transfer catalytic glycosylation and copper-catalyzed azide-alkyne cycloaddition（CuAAC） respectively from 4-methyl-7-hydroxyl coumarin（4-methylumbelliferone）. The structures were characterized by 1H NMR, MS or IR. The fluorescent properties of the coumarin glycosides and triazoylglycosides were studied in different solvents and comoared to those of 4-methyl-7-hydroxyl coumarin.

关键词： Coumarin glycoside Coumarin triazolylglycoside 4-Methyl-7-hydroxyl coumarin Fluorescence property

Synthesis of Bioactive Natural Polymethoxyflavones and Their Vinyl Ether Derivatives

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Chemical Research in Chinese Universities 2012年第4期28卷 631-636页

作者： CAI Shuang-lian LIU Shuang LIU Li wang qiu-an College of Chemistry and Chemical Engineering Hunan UniversityChangsha 410082P.R.China

Bioactive natural polymethoxyflavones 1―6 and their vinyl ether derivatives 7―15 were synthesized by bromination,aromatic nucleophilic substitution,methylation,benzyl protection,Friedel-Crafts acetylation,aldol condensation,cyclization,DDQ dehydrogenation,regioselective demethylation,debenzylation and O-prenylation or O-farnesylation with resorcinol and appropriate substituted benzaldehydes as starting *** them,compounds 7―15 are new *** products 2―4 were firstly total *** syntheses of compounds 1,5 and 6 were efficiently improved by the new synthetic *** structures of all synthetic compounds were confirmed by NMR,IR spectra and MS.

关键词： Flavonoid Polymethoxyflavone Prenylation Farnesylation