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Estimating stellar atmospheric parameters based on Lasso features

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Research in Astronomy and Astrophysics 2014年第4期14卷 423-432页

作者： chuan-xing Liu Pei-Ai Zhang Yu Lu Department of Mathematics Jinan University chool of Mathematical Sciences South China Normal University

With the rapid development of large scale sky surveys like the Sloan Digital Sky Survey （SDSS）, GAIA and LAMOST （Guoshoujing telescope）, stellar spectra can be obtained on an ever-increasing scale. Therefore, it is necessary to estimate stel- lar atmospheric parameters such as Teff, log g and [Fe/H] automatically to achieve the scientific goals and make full use of the potential value of these observations. Feature selection plays a key role in the automatic measurement of atmospheric parameters. We propose to use the least absolute shrinkage selection operator （Lasso） algorithm to select features from stellar spectra. Feature selection can reduce redundancy in spectra, alleviate the influence of noise, improve calculation speed and enhance the robustness of the estimation system. Based on the extracted features, stellar atmospheric param- eters are estimated by the support vector regression model. Three typical schemes are evaluated on spectral data from both the ELODIE library and SDSS. Experimental results show the potential performance to a certain degree. In addition, results show that our method is stable when applied to different spectra.

关键词： methods: data analysis -- stars: fundamental parameters -- techniques:spectroscopic -- surveys

QSPR Studies on lgK_(ow) and lgK_(oc) of Fluorobenzenes and Property Parameters Based on HF and DFT Calculations

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Chinese Journal of Structural Chemistry 2006年第7期25卷 823-829页

作者： ZHANG xing-chuan YU Jing WANG Zun-Yao LIU Hong-Xia College of Biological and Chemical Engineering Jiaxing University Zhejiang 314001 China Department of Material and Chemical Engineering Guilin Institute of Technology Guilin Guangxi 541004 China

Quantum chemistry parameters of 22 fluorobenzenes were computed at six levels using Hartree-Fock and DFT methods. Based on the experimental data of n-octanol/water partition coefficient （lgKow）, a three-parameter （dipole moments （μ）, zero point energy （ZPE） and free energy （G°）） quantitative correlation equation that can predict IgKow was developed using structural and thermodynamic parameters as theoretical descriptors. Similarly, based on experimental data of soil organic carbon sorption coefficient （lgKoc）, the other three-parameter （the most negative atomic net charge of molecule （q^-）, dipole moments （μ） and molecular volume （Vi）） quantitative correlation equation that can predict lgKoc was given. Quantitative correlation equations based on B3LYP/6- 311 G^＊＊ calculation were validated by VIF （variance inflation factors） and t-test and used to predict IgKow and lgKoc of a series of compounds. The result showed that the correlation and prediction ability of lgKoc equations based on three levels of HF/STO-3G, B3LYP/6-31 G^＊ and B3LYP/6- 311G^＊＊ are all more advantageous than those based on AMI.

关键词： fluorobenzene linear solvation energy theory Hartree-Fock density functional theory QSPR n-octanol/water partition coefficient (lgKow) soil organic carbon sorption coefficient (lgKoc)

Effects of heat treatment on the microstructure and mechanical properties of Ni_(3)Al-based superalloys:A review

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International Journal of Minerals,Metallurgy and Materials 2021年第4期28卷 553-566页

作者： Yu-ting Wu Chong Li Ye-fan Li Jing Wu xing-chuan Xia Yong-chang Liu State Key Lab of Hydraulic Engineering Simulation and Safety School of Materials Science&EngineeringTianjin UniversityTianjin 300354China

Ni_(3)Al-based alloys have drawn much attention as candidates for high-temperature structural materials due to their excellent comprehensive *** microstructure and corresponding mechanical properties of Ni_(3)Al-based alloys are known to be susceptible to heat ***,a significant step is to employ various heat treatments to derive the desirable mechanical properties of the *** paper briefly summarizes the recent advances in the microstructure evolution that occurs during the heat treatment of Ni_(3)Al-based *** fromγ′phase andγphase,the precipitations ofβphase,α-Cr precipitates,and carbides are also found in Ni_(3)Al-based alloys with the addition of various alloying *** evolution in morphology,size,and volume fraction of various types of secondary phases during heat treatment are reviewed,involvingγ′phase,βphase,α-Cr precipitate,and *** kinetics of the growth of precipitates are also ***,the influences of heat treatment on the mechanical properties of Ni_(3)Al-based alloys are discussed.

关键词： intermetallics heat treatment microstructure mechanical properties

Hepatocellular carcinoma: Clinical study of long-term survival and choice of treatment modalities

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World Journal of Gastroenterology 2013年第23期19卷 3649-3657页

作者： Ke-Tong Wu Cun-chuan Wang Li-Gong Lu Wei-Dong Zhang Fu-Jun Zhang Feng Shi chuan-xing Li Department of Medical Imaging and Interventional Radiology Cancer Center and State Key Laboratory of Oncology in South China Sun Yat-sen University the Center of Minimally Invasive Surgery First Affiliated Hospital of Jinan University Cancer Center Guangdong General Hospital

AIM: To analyze the prognostic factors of 5-year survival and 10-year survival in hepatocellular carcinoma (HCC) patients, and to explore the reasons for longterm survival and provide choice of treatment modalities for HCC patients. METHODS: From January 1990 to October 2012, 8450 HCC patients were included in a prospective database compiled by the Information Center after hospital admission. Long-term surviving patients were included in a 10-year survival group (520 patients) and a 5-year survival group (1516 patients) for analysis. The long-term survival of HCC patients was defined as the survival of 5 years or longer. Clinical and biologic variables were assessed using univariate and multivariate analyses. The survival of patients was evaluated by follow-up data. RESULTS: The long-term survival of HCC patients was associated with the number of lesions, liver cirrhosis and Child-Pugh classification. It was not found to be associated with tumor diameter, histological stage, and pretreatment level of serum α-fetoprotein. The differences in clinical factors between the 5-year survival and the 10-year survival were found to be the number of lesions, liver cirrhosis, Child-Pugh classification, and time elapsed until first recurrence or metastasis. The survival period of different treatment modalities in the patients who survived for 5 years and 10 years showed significant differences: (in order of significance) surgery alone > surgery-transcatheter arterial chemoembolization (TACE) > TACE-radiofrequency ablation (RFA) > TACE alone > surgery-TACE-RFA. The 10-year survival of HCC patients was not associated with the choice of treatment ***: This retrospective study elucidated survival outcomes, prognostic factors affecting survival and treatment modalities in HCC patients.

关键词： Hepatocellular carcinoma Surgery Radiofrequency ablation Transcatheter arterial chemoembolization Statistical analysis Clinical study

Microstructural Characterization and Phase Separation Sequences During Solidification of Ni_3Al-Based Superalloy

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Acta Metallurgica Sinica(English Letters) 2017年第10期30卷 949-956页

作者： Jing Wu Yong-Chang Liu Chong Li xing-chuan Xia Yu-Ting Wu Hui-Jun Li Hai-Peng Wang State Key Lab of Hydraulic Engineering Simulation and Safety School of Materials Science and EngineeringTianjin University Department of Applied Physics School of ScienceNorthwestern Polytechnical University

As-cast Microstructure of A Designed Polycrystalline Ni3 Al-based Superalloy Is Characterized Using Optical Microscope,scanning Electron Microscope, Transmission Electron Microscope Equipped with Selected Area Diffraction System,and the Intermetallic Phase Transformations Involved During Solidification Process Are Determined Based on Thermal Analysis Measurements. the As-cast Microstructure Is Mainly Composed of 80.63 Vol% Dendritic and 19.37 Vol% Interdendritic Phases,and the Dendrite Is Identified As Quasi-cuboidal γ＇i Phase Connected by γ-channels Where Ultrafine γ＇Ⅱ Particles Are Distributed,and the Interdendritic Phases Are Determined As γ＇-γ Eutectic Structure Consisting of Ye Phase with Dotted Quasi-spherical γ＇e Particles. During Solidification, the Dendrite Firstly Nucleates from Liquid Melt Near 1348 ℃; Subsequently, the Residual Liquidoid Is Transformed into Interdendritic Phases Around 1326 ℃. Afterward, γ＇ Phase Will Precipitate from Dendritic Ymatrix with Two-stage Characteristics, Resulting in the Distinct Precipitation of γ＇Ⅰ and γ＇Ⅱ Phases When Approaching to 1190 And 1043 ℃, Respectively. the Corresponding Transformations Involved During the Solidification Process Can Be Translated As：Liquidoid{Dendrite（γD）（80.63）%→γ＇Ⅰ＋γ（channel）→γ＇Ⅰ＋γ＇Ⅱ＋γ（channel） Residual liquidoid（19.37%）→Interdendrite（γ＇E-γE eutectic）}As-cast

关键词： γ′ phase Microstructure Transformation Solidification Ni3Al-based superalloy

Human Papillomavirus 16E6 Oncogene Mutation in Cervical Cancer

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Chinese Journal of Cancer Research 2009年第2期21卷 97-101页

作者： Feng Sun Xiao-qin Ha Tong-de Lv chuan-ping xing Bin Liu Xiao-zhe Cao Department of Pathology The Second People＇s Hospital of Zhuhai Zhuhai 519020 China Department of General Laboratory Department of Pathology Lanzhou General Hospital of PLALanzhou 730050 China

Objective： Cervical cancer （CC） is the second most common type of cancer in women worldwide, after breast cancer. High-risk human papillomaviruses （HR-HPVs） are considered to be the major causes of cervical cancer. HPV16 is the most common type of HR-HPVs and HPV16 E6 gene is one of the major oncogenes. Specific mutations are considered as dangerous factors causing CC. This study was designed to find mutations of HPV16 E6 and the relationship between the mutations and the happening of CC. Methods： The tissue DNA was extracted from 15 biopsies of CC. Part of HPV16 E6 gene （nucleotide 201-523） was amplified by polymerase chain reaction （PCR） from the CC tissue DNA. The PCR fragments were sequenced and analyzed. Results： The result of PCR showed that the positive rate of HPV16 E6 was 93.33% （14/13）. After sequencing ana analyzing, in the 13 out of 14 PCR fragments, 4 maintained prototype （30.77%）, 8 had a same 350G mutation （61.54%）, and 1 had a 249G mutation （7.69%）. Conclusion： This study suggest that there is a high infection rate of HPV in cervical cancer and most of the HPV16 E6 gene has mutations. Those mutations may have an association with the development of cervical cancer.

关键词： Cervical cancer Human papUlomavirus E6 gene Mutation

Compressive characteristics of closed-cell aluminum foams with different percentages of Er element

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China Foundry 2016年第1期13卷 36-41页

作者： Wei-min Zhao Zan Zhang Yong-ning Wang xing-chuan Xia Hui Feng Jing Wang School of Materials Science and Engineering Hebei University of Technology Tianjin 300130 China Key Lab for Micro- and Nano-Scale Boron Nitride Materials in Hebei Province China CITIC Dicastal Ltd Qinhuangdao 066011 China

In the present study, closed-cell aluminum foams with different percentages of erbium （Er） element were successfully prepared. The distribution and existence form of erbium （Er） element and its effect on the compressive properties of the foams were investigated. Results show that Er uniformly distributes in the cell walls in the forms of Al3Er intermetallic compound and AI-Er solid solutions. Compared with commercially pure aluminum foam, Er-containing foams possess higher micro-hardness, compressive strength and energy absorption capacity due to solid solution strengthening and second phase strengthening effects. Additionally, the amount of Er element should be controlled in the range of 0.10wt.%-0.50wt.% in order to obtain a good combination of compressive strength and energy absorption properties.

关键词： aluminum foams erbium element compressive property melt foaming method

Rare case of omentum-wrapped abscess caused by a fish bone penetrating the terminal ileum

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World Journal of Gastroenterology 2014年第32期20卷 11456-11459页

作者： chuan-xing Wu Bao-Qiang Wu Yun-Fei Duan Dong-Lin Sun Yong Jiang Department of Hepatobiliary Surgery The Third Affiliated Hospital of Soochow University The First People Hospital of Changzhou

Accidentally ingested foreign bodies, for the most part, pass through the gastrointestinal tract, but can cause several complications. Perforation is rare, but can occur in any segment of the gastrointestinal tract. Intestinal perforations due to foreign bodies are rarely diagnosed preoperatively as clinical symptoms are non-specific and they can mimic other abdominal conditions. We describe a case of a 48-year-old patient who was admitted to the emergency room because of severe abdominal pain of 5 d duration. A computed tomography scan showed an undefined liquid collection involving a linear image 35 mm in size, suggestive of a foreign body. On laparotomy, an abscess containing a fish bone was resected. As fish bone ingestion is usually not remembered by the patient, the diagnosis can be delayed. The preoperative diagnosis is frequently acute abdomen of unknown cause. A low threshold of suspicion along with a good clinical history and radiologicalstudies are extremely important in order to make a correct diagnosis.

关键词： Foreign body Fish bone Terminal ileum perforation

FeNiS_(2)/reduced graphene oxide electrocatalysis with reconstruction to generate FeNi oxo/hydroxide as a highly-efficient water oxidation electrocatalyst

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Rare Metals 2022年第12期41卷 4127-4137页

作者： Xiao-Zhen Ren Xue-Hui Li Yu-Jie Peng Guan-Zhi Wang Jie Yin xing-chuan Zhao Wei Wang Xiao-Bai Wang School of Materials Science and Engineering Liaocheng UniversityLiaocheng 252000China School of Metallurgy and Chemistry Engineering Jiangxi University of Science and TechnologyGanzhou 341000China Department of Materials Application Research AVIC Manufacturing Technology InstituteBeijing 100024China

It is critical to developing electrocatalysts with highly active and cost-effective for oxygen evolution to resolve environmental pollution and energy issues,in which FeNi-based nanomaterials hold a great ***,(Fe_(0.33 )Ni_(0.67))S_(2) and(Fe_(0.33 )Ni_(0.67))S_(2)/reduced graphene oxide(rGO)-x%(x=10,20) composites,which exhibited highly efficient oxygen evolution reaction(OER)electrocatalytic activity under alkaline conditions,were synthesized via a hydrothermal approach and following thermal treatment with sulfur *** from the integrated structure of(Fe_(0.33 )Ni_(0.67))S_(2)and support of conductive graphene backbones,(Fe_(0.33 )Ni_(0.67))S_(2)/rGO-20%electrocatalyst showed the best OER activity with an overpotential of 172 mV at 10 mA·cm^(-2)and Tafel slopes of 45 mV·decade^(-1).The composition,phase,and surface structure of the catalyst were characterized before and after OER *** results indicated that crystal phase of the catalyst was reconstructed to the amorphous crystalline features after OER,with oxidation of iron-nickel sulfide and appearance of Ni-Fe oxo/hydroxide species,which may play a crucial role in the high OER performance as the ***,in a two-electrode system towards overall water splitting with(Fe_(0.33 )Ni_(0.67))S_(2)/rGO-20%/NF and Pt/C/NF as the anode and cathode,respectively,the catalysts exhibited excellent catalytic performance with the voltage of only 1.42 V at 10 mA·cm^(-2).

关键词： Ternary nickel-iron sulfide Reduced graphene oxide(rGO) Electrocatalysts Water oxidation Self-reconstruction