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Comparison of cosmological models using standard rulers and candles

Research in Astronomy and Astrophysics 2016年第5期16卷 125-134页

作者： xiao-lei li Shuo Cao xiao-Gang Zheng Song li Marek Biesiada Department of Astronomy Beiiing Normal UniversityBeijing 100875China Department of Physics Capital Normal UniversityBeijing 100048China Department of Astrophysics and Cosmology Institute of PhysicsUniversity of SilesiaUniwersytecka 440-007KatowicePoland

In this paper, we used standard rulers and standard candles （separately and jointly） to explore five popular dark energy models under the assumption of the spatial flatness of the Universe. As standard rulers, we used a data set comprised of 118 galactic scale strong lensing systems （individual standard rulers if properly calibrated for the mass density profile） combined with BAO diagnostics （statistical standard ruler）. Type Ia supernovae served as standard candles. Unlike most previous statistical studies involving strong lensing systems, we relaxed the assumption of a singular isothermal sphere （SIS） in favor of its generalization： the power-law mass density profile. Therefore, along with cosmological model parameters, we fitted the power law index and its first derivative with respect to the redshift （thus allowing for mass density profile evolution）. It turned out that the best fitted ~/parameters are in agreement with each other, irrespective of the cosmological model considered. This demonstrates that galactic strong lensing systems may provide a complementary probe to test the properties of dark energy. The fits for cosmological model parameters which we obtained are in agreement with alternative studies performed by other researchers. Because standard rulers and standard candles have different parameter degeneracies, a combination of stan- dard rulers and standard candles gives much more restrictive results for cosmological parameters. Finally, we attempted an analysis based on model selection using information theoretic criteria （AIC and BIC）. Our results support the claim that the cosmological constant model is still best and there is no （at least statistical） reason to prefer any other more complex model.

关键词： (cosmology:) dark energy -- cosmology: observations -- (cosmology:) cosmological param-eters

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Phase analysis and thermal conductivity of in situ O′-sialon/β-Si_3N_4 composites

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International Journal of Minerals,Metallurgy and Materials 2012年第8期19卷 757-761页

作者： xiao-lei li xiao-liang Chen Hui-ming Ji xiao-hong Sun ling-ge Zhao School of Material Science and Engineering Key Laboratory for Advanced and Machining Technology(Ministry of Education)Tianjin UniversityTianjin 300072China

Typical O＇-sialon-based ceramics, with a formula of Si2-xAlxOl＋xN2-x, where x was set as 0.25, were fabricated by in-situ synthesis Si3N4, Al2O3, and SiO2 powders were used as raw materials, and MgO and Y2O3 were added as sintering additives. All the samples were sintered at different temperatures under a nitrogen pressure of 0.25-0.30 MPa, and their rnicrostructure, phase content, and thermal conductivity were evaluated. The effects of O＇-sialon and β-Si3N4 on the thermal conductivity were analyzed by numerical calculation in detail. In the case of the similar porosity, the thermal conductivity of O＇-sialon-based ceramics decreased with the ratio of O＇-sialon/β-Si3N4 increasing. When the ratio was 12, the thermal conductivity of O＇-sialon ceramics sintered at 1360℃ was 1.197 W.m-1.K-1.

关键词： ceramic materials sintering phase composition thermal conductivity numerical calculation

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Experimental analysis of crack tip fields in rubber materials under large deformation

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Acta Mechanica Sinica 2012年第2期28卷 432-437页

作者： Xia xiao Hai-Peng Song Yi-Lan Kang xiao-lei li xiao-Hua Tan Hao-Yun Tan Department of Mechanics Tianjin University300072 TianjinChina School of Mechanical Engineering Tianjin Polytechnic University300387 TianjinChina Hebei University of Technology 300401 TianjinChina

A three-nested-deformation model is proposed to describe crack-tip fields in rubber-like materials with large deformation. The model is inspired by the distribution of the measured in-plane and out-of-plane deformation. The in- plane displacement of crack-tip fields under both Mode 1 and mixed-mode （Mode I-II） fracture conditions is measured by using the digital Moir6 method. The deformation character- istics and experimental sector division mode are investigated by comparing the measured displacement fields under differ- ent fracture modes. The out-of-plane displacement field near the crack tip is measured using the three-dimensional digital speckle correlation method.

关键词： Crack-tip field. Large deformation Sector divi- sion mode. Three-nested-deformation model- Digital Moir6 method

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A Sound Field Separation and Reconstruction Technique Based on Reciprocity Theorem and Fourier Transform

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Chinese Physics Letters 2018年第11期35卷 42-45页

作者： xiao-lei li Ning Wang Da-Zhi Gao Qi li Department of Marine Technology Ocean University of ChinaQingdao 266100 College of Underwater Acoustic Engineering Harbin Engineering UniversityHarbin 150006

We show a method to separate the sound field radiated by a signal source from the sound field radiated by noise sources and to reconstruct the sound field radiated by the signal source. The proposed method is based on reciprocity theorem and the Fourier transform. Both the sound field and its gradient on a measurement surface are needed in the method. Evanescent waves are considered in the method, which ensures a high resolution reconstruction in the near field region of the signal source when evanescent waves can be measured. A simulation is given to verify the method and the influence of measurement noise on the method is discussed.

关键词： A Sound Field Separation and Reconstruction Technique Based on Reciprocity Theorem and Fourier Transform

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A new aryltetrahydronaphthalene lignan from Epimedium brevicornum

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Chinese Chemical Letters 2011年第1期22卷 85-87页

作者： Hai Zhou li Guo Jun Luo Hong Mei li xiao lei li Rong Tao li The college of life Science and Technology Kunming University of Science and Technology Kunming 650224 China

A new aryltetrahydronaphthalene lignan, （＋）-cycloolivil formaldehyde condensate （1）, was isolated from the whole plants of Epimedium brevicornum （Berberidaceae）. Its structure was elucidated on the basis of MS,... 详细信息

关键词： Epimedium brevicornum lignan Cycloolivil formaldehyde condensate

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Effects of Processing Variables on Microstructure and Yield Ratio of High Strength Constructional Steels

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Journal of Iron and Steel Research International 2016年第8期23卷 815-821页

作者： Jian KANG Cheng-ning li xiao-lei li Jin-hua ZHAO Guo YUAN Guo-dong WANG State Key Laboratory of Rolling and Automation Northeastern University Shenyang 110819 Liaoning China Shougang Qian'an Iron and Steel Co. Ltd. Qian'an 064404 Hebei China

The process of“controlled rolling＋relaxation＋ultra fast cooling（UFC）”for high strength constructional steel with low yield ratio was *** and corresponding relationship with low yield ratio were *** results showed that the constructional steels with multiphase microstructure of bainitic ferrite,martensite-austenite（M-A）and lath bainite were obtained through the creative *** grain size decreased with the decrease in finish rolling temperature,which enhanced the strength by the grain refinement *** proper relaxation treatment promoted the bainitic ferrite lath width and the formation of blocky M-A *** addition,both the tensile and yield strength increased with the decrease in finish rolling temperature and UFC final temperature,but the yield strength increased more significantly than tensile strength,which caused the increase in yield *** using the process of“controlled rolling＋relaxation＋ultra fast cooling”,the excellent comprehensive mechanical properties of 780 MPa grade constructional steels of 12-40 mm in thickness were achieved.

关键词： relaxation tensile martensite rolling steels refinement ferrite austenite creative finish

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Adaptive online prediction method based on LS-SVR and its application in an electronic system

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Journal of Zhejiang University-Science C(Computers and Electronics) 2012年第12期13卷 881-890页

作者： Yang-ming GUO Cong-bao RAN xiao-lei li Jie-zhong MA School of Computer Science and Technology Northwestern Polytechnical University Xi'an 710072 China

Health trend prediction has become an effective way to ensure the safe operation of highly reliable systems,and online prediction is always necessary in many real *** simultaneously obtain better or acceptable online prediction accuracy and shorter computing time,we propose a new adaptive online method based on least squares support vector regression(LS-SVR).This method adopts two *** approach is that we delete certain support vectors by judging the linear correlation among the samples to increase the sparseness of the prediction *** approach can control the loss of useful information in sample data,improve the generalization capability of the prediction model,and reduce the prediction *** other approach is that we reduce the number of traditional LS-SVR parameters and establish a modified simple prediction *** approach can reduce the calculation time in the process of adaptive online *** and a certain electric system application indicate preliminarily that the proposed method is an effective prediction approach for its good prediction accuracy and low computing time.

关键词： Adaptive online prediction Least squares support vector regression(LS-SVR) Electronic system

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Quasistatic and Dynamic Tensile Behavior of Zr_(52.5)Al_(10)Ni_(10)Cu_(15)Be_(12.5) Bulk Metallic Glass

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Journal of Materials Science & Technology 2003年第5期19卷 410-412页

作者： Xueshan xiao, Weihuo li, lei XIA, Shoushi FANG, Qin HUA and Yuanda DONGInstitute of Materials, Shanghai University, Shanghai 200072, China Inst. of Mat. Shanghai Univ. Shanghai 200072 China

Quasistatic and dynamic tensile behavior of Zr52.5Al10Ni10Cu15Be12.5 bulk amorphous alloy was investigated at the strain rates of 10-4-103 s-1 by using a Shimadzu AG-100KNA autograph and a pneumatic tensile impact tester. It was shown that the tensile fracture strength and the fracture morphology were sensitive to the strain rate. With the increase of the strain rate, the tensile fracture strength decreased and the fracture morphology changed from cleavage into quasi-cleavage, and then into a mixture of microvoid-coalescence dimples and quasi-cleavage veins.

关键词： Mechanical properties Bulk metallic glass Fracture

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Geological resources and environmental carrying capacity evaluation review,theory, and practice in China

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China Geology 2018年第4期1卷 556-565页

作者： Rui-min li Zhi-qiang Yin Yi Wang xiao-lei li Qiong liu Meng-meng Gao China Institute of Geo-Environment Monitoring Beijing 100081China Technical Guidance Center of Geological hazards Ministry of Natural ResourcesBeijing 100081China

Evaluations of resources and environmental carrying capacities (GRECC)are the premise of land space planning and use *** allocations and environmental capacity are the basic conditions that restrict development in a *** this paper,based on a systematic review of China's geological environment,groundwater resources,mineral resources,other geological resources and the environmental carrying capacity research status,the relationship between the natural resource environmental system and the socio-economic system is *** a "coordination theory of resources and environmental carrying"is ***,on the basis of an evaluation experiment performed at different scales and for different types of regions,the technical methods for an evaluation of the geological resources and environmental carrying capacity at the regional (inter-provincial)and provincial scales in China are established for the first *** paper presents a standardized method based on technical ideas, evaluation methods,and index systems for geological resource and environmental carrying capacity ***,an evaluation of the groundwater resource carrying capacity in China is used as an example for the demonstration of the groundwater resource background and use of state evaluation methods.

关键词： Geological environment Groundwater resources Resource and environment Carrying capacity Evaluation

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Right cryptorchid testicular metastasis from descending colon carcinoma： a case report of ＂Krukenberg tumor＂ in male

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Asian Journal of Andrology 2015年第1期17卷 171-172页

作者： Qi Xu xiao-lei li Ya-Wei Yu Lai-Rong Dong Jian-Guo Shen lin-Bo Wang Department of Surgical Oncology Affiliated Sir Run Run Shaw Hospital Zhejiang University School of Medicine Hangzhou China Department of Surgical Oncology The Second Hospital of Jiaxing City Jiaxing China Department of Pathology The Second Hospital of Jiaxing City Jiaxing China.

Dear Editor, We present here a case report of＂Krukenberg tumor＂ in male. In 1896, Friedrich Krukenberg （1871 - 1946）, a German gynecologist and pathologist, described what he presumed as a new type of primary ovarian neoplasm. The true metastatic nature of this lesion was established 6 years later and termed as＂Krukenberg tumor＂？ Now, the term ＂Krukenberg tumor＂ has been used either as a broad definition to indicate all metastatic tumors to the ovaries or to describe just metastatic tumors from the gastrointestinal tract containing the typical signet ring cell with intracellular mucin.2-6 Our case, as an analog in male, has criteria to be called ＂Krukenberg tumor＂ in male.

关键词： Right cryptorchid testicular metastasis

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