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On the Global Existence and Uniqueness of Solutions to Prandtl's System

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Acta Mathematica Sinica,English Series 2009年第1期25卷 109-132页

作者： Xin ying XU Jun ning ZHAO Department of Mathematics Xiamen University Xiamen Fujian 361005 P. R. China

In this paper, we consider the Prandtl system for the non-stationary boundary layer in the vicinity of a point where the outer flow has zero velocity. It is assumed that U（t, x, y） = x^mU1（t, x）, where 0 〈 x 〈 L and m 〉 1. We establish the global existence of the weak solution to this problem. Moreover the uniqueness of the weak solution is proved.

关键词： boundary layer global solution uniqueness

Seismic data reconstruction based on low dimensional manifold model

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Petroleum Science 2022年第2期19卷 518-533页

作者： nan-ying Lan Fan-Chang Zhang Xing-Yao Yin School of Geosciences China University of Petroleum(East China)QingdaoShandong 266580China

Seismic data reconstruction is an essential and yet fundamental step in seismic data processing workflow,which is of profound significance to improve migration imaging quality,multiple suppression effect,and seismic inversion *** methods play a central role in solving the underdetermined inverse problem of seismic data *** this paper,a novel regularization approach is proposed,the low dimensional manifold model(LDMM),for reconstructing the missing seismic *** work relies on the fact that seismic patches always occupy a low dimensional ***,we exploit the dimension of the seismic patches manifold as a regularization term in the reconstruction problem,and reconstruct the missing seismic data by enforcing low dimensionality on this *** crucial procedure of the proposed method is to solve the dimension of the patches *** this,we adopt an efficient dimensionality calculation method based on low-rank approximation,which provides a reliable safeguard to enforce the constraints in the reconstruction *** experiments performed on synthetic and field seismic data demonstrate that,compared with the curvelet-based sparsity-promoting L1-norm minimization method and the multichannel singular spectrum analysis method,the proposed method obtains state-of-the-art reconstruction results.

关键词： Seismic data reconstruction Low dimensional manifold model Regularization Low-rank approximation

Agrobacterium tumefaciens-mediated transformation of modern rose(Rosa hybrida)using leaf-derived embryogenic callus

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Horticultural Plant Journal 2021年第4期7卷 359-366页

作者： Guoqin Liu Yuan Yuan Hui Jiang ying Bao Guogui ning Liangjun Zhao Xiaofeng Zhou Hougao Zhou Junping Gao nan Ma State Key Laboratory of Agrobiotechnology Beijing Key Laboratory of Development and Quality Control of Ornamental CropsDepartment of Ornamental HorticultureCollege of HorticultureChina Agricultural UniversityBeijing 100193China Faculty of Life Science Tangshan Normal UniversityTangshanHebei 063000China Key Laboratory of Horticultural Plant Biology College of Horticulture and Forestry SciencesHuazhong Agricultural UniversityWuhan 430070China College Horticulture&Landscape Architecture Zhongkai University of Agriculture and EngineeringGuangzhou 510225China

Rose(Rosa hybrida)is widely used for cut flowers and as garden *** and efficient transformation system is required for functional genomics of ***,we established an efficient transformation method for rose using Agrobacterium tumefaciens-mediated transformation of embryogenic *** rose leaves were used as explants to induce somatic embryos,which were subjected to transformation with *** strain GV3101 using Green Fluorescence Protein(GFP)as a marker *** took about 8 months to generate transgenic shoots from embryogenic ***,RT-PCR,Southern and Western blotting,as well as stereoscopic fluorescence microscopy analysis demonstrated that GFP transgenes integrated stably into the rose *** to our data,a transformation efficiency of up to 6%can be achieved by following this optimized protocol.

关键词： Rose Rosa hybrida Leaf Somatic embryos Agrobacterium tumefaciens Genetic transformation

Controllable combustion behaviors of the laser-controlled solid propellant

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Defence Technology（防务技术） 2022年第1期18卷 38-48页

作者： Bu-ren Duan Hao-nan Zhang Li-zhi Wu Zuo-hao Hua Zi-jing Bao ning Guo ying-hua Ye Rui-qi Shen School of Chemical Engineering Narging University of Science and Technology Narjing 210094China Instifute of Space Propulsion Nanjing University of Science and Technology Nanjing 210094China Micro-nano Energetic Devices Key Laboratory Ministry of Industry and Informnation TedhinologyNanjing210094China Shanghai Space Propulsion Technology Research Instirute Shanghai201109China

Microsatellites have been widely applied in the fields of communication,remote sensing,navigation and science exploration due to its characteristics of low cost,flexible launch mode and short development ***,conventional solid-propellant have difficulties in starting and interrupting combustion because combustion is autonomously sustained after ignition Herein,we proposed a new type of solid-propellant named laser-controlled solid propellant,which is sensitive to laser irradiation and can be started or interrupted by switching on/off the continuous wave *** demonstrate the feasibility and investigate the controllable combustion behaviors under different laser on/off conditions,the combus tion parameters including burning rate,ignition delay time and platform pressure were tested using pressure sensor,high-speed camera and thermographic *** results showed that the increase of laser-on or laser-off duration both will lead to the decrease of propellant combustion performance during re-ignition and re-combustion *** is mainly attributed to the laser attenuation caused by the accumulation of combustion residue and the change of chamber ambient *** the multiple ignition tests revealed that the increased chamber ambient temperature after combustion can make up for the energy loss of laser attenuation and expansion of chamber ***,the laser-controlled combustion performance of solid propellant displayed a decrease trend with the addi-tion of ignition ***,the results still exchibited good laser-controlled agility of laser-controlled solid propellant and manifested its inspiring potential in many aspects of space missions.

关键词： Laser-con trolled solid propellant Laser ablation Multiple ignition Controllable combustion Combustion be haviors

Characteristics of molecular weight distribution of dissolved organic matter in bromide-containing water and disinfection by-product formation properties during treatment processes

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Journal of Environmental Sciences 2018年第3期30卷 179-189页

作者： ying Zhang ning Zhang Peng Zhao Zhiguang Niu MOE Key Laboratory of Pollution Processes and Environmental Criteria College of Environmental Science and Engineering Nankai University School of Marine Science and Technology Tianjin University

The characteristics of dissolved organic matter（DOM） and bromide ion concentration have a significant influence on the formation of disinfection by-products（DBPs）. In order to identify the main DBP precursors, DOM was divided into five fractions based on molecular weight（MW）, trihalomethane formation potential and haloacetic acid formation potential were determined for fractions, and the change in contents of different fractions and total DBPs during treatment processes（pre-chlorination, coagulation, sand filtration,disinfection） were studied. Moreover, the relationship between bromide concentration and DBP generation characteristics in processes was also analyzed. The results showed that the main DBP precursors were the fraction with MW 1 k Da and fraction with MW 3-10 k Da, and the DBP＇s generation ability of lower molecular weight DOM（ 10 k Da） was higher than that of higher molecular weight DOM. During different processes,pre-chlorination and disinfection had limited effect on removing organics but could alter the MW distribution, and coagulation and filtration could effectively remove organics with higher MW. For DBPs, trihalomethanes（THMs） were mainly generated in pre-chlorination and disinfection, while haloacetic acids（HAAs） were mostly generated during pre-chlorination; coagulation and sand filtration had little effect on THMs but resulted in a slight removal of HAAs. In addition, the results of ANOVA tests suggested that molecular sizes and treatment processes have significant influence on DBP formation. With increasing bromide concentration, the brominated DBPs significantly increased, but the bromine incorporation factor in the processes was basically consistent at each concentration.

关键词： Disinfection by-products Molecular weight distribution Bromine incorporation factor Water treatmentUltrafiltration

A new nonparametric stability test with an application to major Chinese macroeconomic time series

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Applied Mathematics(A Journal of Chinese Universities) 2013年第1期28卷 1-16页

作者： CAI nan CAI Zong-wu FANG ying The Wang Yanan Institute for Studies in Economics MOE Key Laboratory of Econometrics (Xia- men University) Fujian Provincial Key Laboratory of Statistical Science Xiamen University Department of Mathematics and Statistics University of North Carolina at Charlotte

In this paper, we propose a new test for testing the stability in macroeconomic time series, based on the LASSO variable selection approach and nonparametric estimation of a time-varying model. The wild bootstrap is employed to obtain its data-dependent critical values. We apply the new method to test the stability of bivariate relations among 92 major Chinese macroeconomic time series. We find that more than 70% bivariate relations are significantly unstable.

关键词： LASSO stability test time-varying coefficients model wild bootstrap.

New Soluble Near-Infrared Dyes Based on Terrylene Diimides with Four Aromatic Heterocycles

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Chinese Journal of Chemistry 2014年第4期32卷 356-360页

作者： Huimin Wei nan Jiang nan Zhao ying Zhang Baoxiang Gao College of Chemistry and Environmental Science Hebei UniversityBaodingHebei 071002China Key Laboratory of Medicinal Chemistry and Molecular Diagnosis Hebei UniversityBaodingHebei 071002China

Terrylene diimides with four aromatic heterocycles(AHTDIs)were synthesized under Stille Cross-coupling conditions and fully characterized by NMR and mass *** aggregation of the terrylene diimide(TDI)was suppressed by four heterocycles substituents on the bay region,and these AHTDIs exhibited good solubility in common organic *** effects of the substituted groups on the optical and electrochemical properties were also *** introduction of four aromatic heterocycles on the bay of TDI resulted in significant red-shifts of the absorption peak(100 nm),corresponding to a decrease in the band gap from 1.82 to 1.50 ***,with four rich electron aromatic heterocycles,the AHTDIs showed 280 mV negative-shifts of first oxidation poten-tials and a new oxidation wave,corresponding to an increase in the HOMO levels from−5.60 to−5.28 eV.

关键词： terrylene diimides aromatic heterocycles near-infrared dyes optoelectronic properties

Research on Risk Identification and Industrial Governance of Digital Education Products Based on Data Annotation Technology

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China Communications 2024年第3期21卷 273-282页

作者： Tong Lili Zeng Jia Di ying Wang nan Faculty of Education Beijing Normal University Beijing 100875China China Unicom Beijing 102211China

The social transformation brought aboutby digital technology is deeply impacting various *** education products, with core technologiessuch as 5G, AI, IoT (Internet of Things),etc., are continuously penetrating areas such as teaching,management, and evaluation. Apps, miniprograms,and emerging large-scale models are providingexcellent knowledge performance and flexiblecross-media output. However, they also exposerisks such as content discrimination and algorithmcommercialization. This paper conducts anevidence-based analysis of digital education productrisks from four dimensions: “digital resourcesinformationdissemination-algorithm design-cognitiveassessment”. It breaks through corresponding identificationtechnologies and, relying on the diverse characteristicsof governance systems, explores governancestrategies for digital education products from the threedomains of “regulators-developers-users”.

关键词： digital education products industry governance risk identification

Effect of Tongxieyaofang decoction on colonic mucosal protein expression profiles in rats with visceral hypersensitivity

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Journal of Traditional Chinese Medicine 2020年第2期40卷 245-252页

作者： Lin Yongjun Ding ying Lü Bin Liu nan Department of Intensive Care Unit Sir Run Run Shaw HospitalMedicine School of Zhejiang UniversityHangzhou 310016China Department of Intensive Care Unit Sir Run Run Shaw Hospital XiaSha CampusMedicine School of Zhejiang UniversityHangzhou 310018China Department of Gastroenterology the First Affiliated Hospital of Zhejiang Chinese Medical UniversityHangzhou 310006China

OBJECTIVE: To explore the underlying mechanism of action of Tongxieyaofang decoction in rats with visceral hypersensitivity using proteomics ***: Twenty-four female Sprague-Dawley rats were randomly divided into three groups: control group, irritable bowel syndrome(IBS) group and Tongxieyaofang treatment group. An IBS model, characterized as visceral hypersensitivity, was established using the odour of mothballs as conditional stimulation and colorectal distension combined with classic physical restraint as non-conditional stimulation. Rats were intragastrically treated with Tongxieyaofang(2 or 4 m L · kg^(-1)· d^(-1))for 4 weeks. On the 45 th day, the rats were dissected and the colonic mucosal proteins were extracted. Differential protein spots were screened by fluorescent two-dimensional differential gel electrophoresis(2 D-DIGE), and identified by matrix-assisted laser desorption/ionisation time of flight mass spectrometry(MALDI-TOF-MS). Western blotting experiments were performed to verify the changes observed in 2 D-DIGE and ***: It was found that the visceral sensitivity of rats in the Tongxieyaofang treatment group(4 m L/kg) was lower than that in the IBS group(P <0.01). Sixty-one protein spots were differentially expressed between the IBS group and the Tongxieyaofang treatment group. Of these, 23 spots were upregulated in the Tongxieyaofang treatment group, while 38 spots were downregulated. Three specific proteins were successfully identified from the five protein spots with the most obvious changes. The two upregulated proteins were transgelin(TAGLN) and acetaldehyde dehydrogenase 2(Aldh2) and the downregulated protein was cytokeratin 8(CK8).CONCLUSION: Tongxieyaofang can dose-dependently ameliorate visceral hypersensitivity in rats and the mechanism of action may involve the upregulation of TAGLN and Aldh2 and the downregulation of CK8.

关键词： Irritable bowel syndrome Hypersensitivity Acetaldehyde dehydrogenase inhibitor Keratin-8 Tongxieyaofang