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Assessments of coefficients of linear thermal expansions for magnetic elements Fe, Co and Ni

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Rare Metals 2016年第6期35卷 481-486页

作者： Dan li xiao-bo li bo Zhang Chen Chen School of Mechanical Engineering Xiangtan University Xiangtan 411105 China Key Laboratory of Materials Design and Preparation Technology of Hunan Province Xiangtan 411105 China

The coefficients of linear thermal expansions （CLEs） of magnetic elements Fe, Co and Ni were assessed from experimental information using theoretical models combined with MATLAB calculations. Model parameters can be determined accurately, and the assessed data are in good agreement with the experimental results. To facilitate the assessments, theories of thermal expansion were applied to separate CLEs into its nonmagnetic and magnetic components. The calculations of nonmagnetic contribution to CLEs were based on the modified Gruineisen- Debye model, in which the Debye temperature was regarded as an undetermined constant. In order to put the prediction of CLEs at the magnetic transition region on a sound physical basis, two kinds of theoretical models were innovatively used to calculate the magnetic contribution to CLEs, i.e., the Bragg-Williams model and the Fermi-Dirac distribution function. Model parameters were evaluated from experimental data using least square method. Detailed comparisons were made with the published experimental data and the calculated total CLEs. A satisfactory agreement is reached.

关键词： Coefficients of linear thermal expansion Magnetic elements Theoretical models

Characterization of the Grain Structures in Vacuum-Assist HighPressure Die Casting AM60B Alloy

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Acta Metallurgica Sinica(English Letters) 2016年第7期29卷 619-628页

作者： xiao-bo li Shou-Mei Xiong Zhi-Peng Guo School of Materials Science and Engineering Tsinghua University Key Laboratory for Advanced Materials Processing Technology Ministry of EducationTsinghua University

The structures in vacuum-assist high-pressure die casting （HPDC） AM60B alloy were studied by using an optical microscope and a scanning electron microscope with an energy dispersive spectrometer. It was found that the HPDC under the vacuum could significantly change the morphology and distribution of the microstructure. For both conventional and vacuum-assist HPDC processes, the externally solidified crystals （ESCs） tended to aggregate in the center along the thickness direction of the castings. Besides, the aggregation was more pronounced, and the number of ESCs decreased, and the ESCs tended to become smaller and more globular, as the distance between the specimen location and runner increased. Compared with the conventional castings, the vacuum-assist HPDC can significantly reduce the size and amount of ESCs, and the ESCs tended to be more globular. For the distribution of ESCs along the thickness of the specimens, the aggregation tendency was more pronounced in vacuum-assist die castings than that in conventional castings. Besides, the distribution of ESCs at different locations was more converged in the vacuum-assist HPDC than that in the conventional HPDC.

关键词： AM60B alloy Grain structure Vacuum-assist high-pressure die casting Externally solidifiedcrystals

Point source detection performance of Hard X-ray Modulation Telescope imaging observation

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Research in Astronomy and Astrophysics 2015年第11期15卷 1905-1916页

作者： Zhuo-Xi Huo Yi-Ming li xiao-bo li Jian-Feng Zhou Department of Physics Tsinghua University Centre for Astrophysics Tsinghua University Laboratoire de l'Accélérateur linéaire Institute of High Energy Physics Chinese Academy of Sciences Department of Engineering Physics Tsinghua University

The Hard X-ray Modulation Telescope（HXMT） will perform an all-sky survey in the hard X-ray band as well as deep imaging of a series of small sky *** expect various compact objects to be detected in these imaging observations. Point source detection performance of HXMT imaging observation depends not only on the instrument but also on the data analysis method that is applied since images are reconstructed from HXMT observed data with numerical methods. The denoising technique used plays an important part in the HXMT imaging data analysis pipeline along with demodulation and source detection. In this paper we have implemented several methods for denoising HXMT data and evaluated the point source detection performances in terms of sensitivities and location accuracies. The results show that direct demodulation with 1-fold cross-correlation should be the default reconstruction and regularization method, although both sensitivity and location accuracy could be further improved by selecting and tuning numerical methods in data analysis used for HXMT imaging observations.

关键词： regularization reconstructed selecting demodulation pixel wavelet pipeline neighborhood tuning histogram

Genetic Analysis and Mapping of the Dominant Dwarfing Gene D-53 in Rice

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Journal of Integrative Plant Biology 2006年第4期48卷 447-452页

作者： li-Rong Wei Ji-Chen Xu xiao-bo li Qian Qian li-Huang Zhu Institute of Genetics and Developmental Biology the Chinese Academy of Sciences Beijing 100101 China State Key Laboratory of Rice Biology China National Rice Research Institute Hangzhou 310006 China

The dwarfing gene D-53 Is one of a few dominant genes for dwarfing In rice （Oryza satlva L.）. In the present study, our genetic analysis confirmed that mutant characteristics including dwarfing, profuse tlllerlng, thin stems and small panicles are all controlled by the dominant D-53 gene. We measured the length of each Internode of KL908, a D-53-carrylng line, and classified the dwarfism of KL908 Into the dn-type. In addition, we measured elongation of the second sheath and a-amylase activity In the endosperm, and we characterized KL908 as a dwarf mutant that was neither glbberelllc acid-deficient nor glbberelllc acid-Insensitive. Using a large F2 population obtained by crossing KL908 with a wild-type variety, NJ6, the D-53 gene was mapped to the terminal region of the short arm of chromosome 11, with one simple sequence repeat marker, Ds3, co-segregating, and the other, K81114, located 0.6 cM away.

关键词： dominant dwarf gene genetic analysis genetic mapping rice.

A multi-paradigm decision modeling framework for combat system effectiveness measurement based on domain-specific modeling

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Journal of Zhejiang University-Science C(Computers and Electronics) 2013年第5期14卷 311-331页

作者： xiao-bo li Yong-lin LEI Hans VANGHELUWE Wei-ping WANG Qun li Institute of Simulation Engineering College of Information Systems and ManagementNational University of Defense Technology Department of Mathematics and Computer Science University of Antwerp

Decision modeling is an essential part of the combat system effectiveness simulation (CoSES), which needs to cope with the cognitive quality, diversity, flexibility, and higher abstraction of decision making. In this paper, a multi-paradigm decision modeling framework is proposed to support decision modeling at three levels of abstraction based on domain-specific modeling (DSM). This framework designs a domain-specific modeling language (DSML) for decision modeling to raise the abstraction level of modeling, transforms the domain-specific models to formalism-based models to enable formal analysis and early verification and validation, and implements the semantics of the DSML based on a Python scripts framework which incorporates the decision model into the whole simulation system. The case study shows that the proposed approach incorporates domain expertise and facilitates domain modeler's participation in CoSES to formulate the problem using DSML in the problem domain, and enables formal analysis and automatic implementation of the decision model in the solution domain.

关键词： Multi-paradigm modeling (MPM) Decision modeling Domain-specific modeling (DSM) Effectiveness measurement Model transformation

Hydrazine-Cadmium Tellurite Hybrid Microcrystals: An Efficient Precursor to Porous Cadmium Telluride and Tellurium Architectures Through Its Thermal Decomposition

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Nano Research 2010年第2期3卷 81-91页

作者： Hong-Bin Yao xiao-bo li Si-Yuan Ai Shu-Hong Yu Division of Nanomaterials and Chemistry Hefei National Laboratory for Physical Sciences at MicroscaleDepartment of ChemistryUniversity of Science and Technology of ChinaHefei 230026China

Well-defined platelet-like hydrazine-cadmium tellurite hybrid microcrystals have been synthesized by a solvothermal reaction of cadmium chloride,sodium tellurite,and hydrazine hydrate in a mixed solvent containing n-propylamine and deionized *** formula of the hybrid platelet-like microcrystals has been proposed based on a combination of powder X-ray diffraction pattern(PXRD),elemental analysis,thermogravimetic analysis(TGA),and X-ray photoelectron spectroscopy(XPS).Controlled thermal decomposition of this hybrid precursor can lead to the formation of porous platelet-like *** porous cadmium telluride architectures were obtained by using hydrochloric acid to dissolve CdTeO3 remaining in the sample after thermal decomposition at 450°*** addition,unique nanoporous tellurium architectures were obtained by using hydrochloric acid to dissolve the amorphous Cd(N2H4)TeO3 formed after thermal decomposition at 300°C,followed by an in situ topotactic reaction between the residual three-dimensional(3-D)skeleton of cadmium telluride nanocrystallites and−***-Emmett-Teller(BET)analysis and a study of the optical properties of these porous cadmium telluride and tellurium materials have also been carried out.

关键词： Thermal decomposition hydrazine hybrid porous architecture tellurium

Association between autoimmune gastritis and gastric polyps:Clinical characteristics and risk factors

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World Journal of Gastrointestinal Oncology 2025年第1期17卷 73-87页

作者： Jing-Zheng Jin xiao liang Shu-Peng liu Rui-Lan Wang Qing-Wei Zhang Yu-Feng Shen xiao-bo li Division of Gastroenterology and Hepatology Renji HospitalShanghai Jiao Tong University School of MedicineShanghai 200127China Division of Gastroenterology and Hepatology Shanghai Institute of Digestive DiseasesShanghai 200001China Division of Gastroenterology and Hepatology Renji Hospital Affiliated to Shanghai Jiao Tong University School of MedicineShanghai 200127China Division of Gastroenterology and Hepatology Sichuan Armed Police Corps HospitalLeshan 610041Sichuan ProvinceChina Division of Gastroenterology and Hepatology NHC Key Laboratory of Digestive DiseasesRenji HospitalShanghai Jiao Tong University School of MedicineShanghai 200127China Department of Gastroenterology Renji Hospital Affiliated to Shanghai Jiao Tong University School of Medicine Shanghai Institute of Digestive DiseasesShanghai 200127China

BACKGROUND The relationship between autoimmune gastritis(AIG)and gastric polyps(GPs)is not well *** To explore the clinical characteristics and risk factors of AIG with GPs in *** This double center retrospective study included 530 patients diagnosed with AIG from July 2019 to July *** collected clinical,biochemical,serological,and demographic data were of each *** regression analyses,both multivariate and univariate,were conducted to pinpoint independent risk factors for GPs in patients with AIG *** operating characteristic curves were utilized to establish the optimal cutoff values,sensitivity,and specificity of these risk factors for predicting GPs in patients with *** Patients with GPs had a higher median age than those without GPs[61(52.25-69)years vs 58(47-66)years,P=0.006].The gastrin-17 levels were significantly elevated in patients with GPs compared with those without GPs[91.9(34.2-138.9)pmol/mL vs 60.9(12.6-98.4)pmol/mL,Pbody(PCA)antibody was higher in these patients than in those without GPs(88.6%vs 73.6%,Plike cells hyperplasia(OR=3.116,Plike cells hyperplasia are significant risk factor for the development of GPs in patients with *** gastrin-17 levels may also play a role in this *** findings suggest potential targets for further research and therapeutic intervention in managing GPs in patients with AIG.

关键词： Autoimmune gastritis Gastric polyps Neuroendocrine tumor Risk factors Nomogram

Operative link on gastritis assessment stage is an appropriate predictor of early gastric cancer

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World Journal of Gastroenterology 2016年第13期22卷 3670-3678页

作者： Ying Zhou Hai-Yan li Jing-Jing Zhang xiao-Yu Chen Zhi-Zheng Ge xiao-bo li Division of Gastroenterology and Hepatology Ren Ji Hospital School of Medicine Shanghai Jiao Tong University Shanghai Institute of Digestive Disease

AIM: To assess the predictive value of Operative link on Gastritis Assessment (OLGA) and Operative link on Gastric Intestinal Metaplasia Assessment (OLGIM) stages in gastric ***: A prospective study was conducted with 71 patients with early gastric cancer (EGC) and 156 patients with non-EGC. All patients underwent endoscopic examination and systematic biopsy. Outcome measures were assessed and compared, including the Japanese endoscopic gastric atrophy (EGA) classification method and the modified OLGA method as well as the modified OLGIM method. Helicobacter pylori (H. pylori) status was determined for all study participants. Stepwise logistic regression modeling was performed to analyze correlations between EGC and the EGA, OLGA and OLGIM ***: For patients with EGC and patients with non-EGC, the proportions of moderate-to-severe EGA cases were 64.8% and 44.9%, respectively (P = 0.005), the proportions of OLGA stages III-IV cases were 52.1% and 22.4%, respectively (P ling showed significant correlations between EGC and moderate-to-severe EGA (OR = 1.95, 95% CI: 1.06-3.58, P = 0.031) and OLGA stages III-IV (OR = 3.14, 95%CI: 1.71-5.81, P litate early detection of gastric cancer.

关键词： Early gastric cancer Operative link on Gastritis Assessment/Operative link on Gastric Intestinal Metaplasia Assessment stage Endoscopic gastric atrophy classification Screening Endoscopy

Defect band formation in high pressure die casting AE44 magnesium alloy

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China Foundry 2022年第3期19卷 201-210页

作者： Ying-ying Hou Meng-wu Wu Feng Huang xiao-bo li Shou-mei Xiong Hubei Key Laboratory of Advanced Technology for Automotive Components Wuhan University of TechnologyWuhan 430070China School of Materials Science and Engineering Tsinghua UniversityBeijing 100084China

The characteristics of defect bands in the microstructure of high pressure die casting(HPDC)AE44 magnesium alloy were *** attention was paid to the effects of process parameters during the HPDC process and casting structure on the distribution of defect *** show that the defect bands are solute segregation bands with the enrichment of Al,Ce and La elements,which are basically in the form of Al_(11)RE_(3) *** is no obvious aggregation of porosities in the defect *** width of the inner defect band is 4-8 times larger than that of the outer *** variation trends of the distribution of the inner and outer defect bands are not consistent under different process parameters and at different locations of *** is due to the discrepancy between the formation mechanisms of double defect *** filling and solidification behavior of the melt near the chilling layer is very complicated,which finally leads to a fluctuation of the width and location of the outer defect *** affecting the content and aggregation degree of externally solidified crystals(ESCs)in the cross section of die castings,the process parameters and casting structure have a great influence on the distribution of the inner defect band.

关键词： high pressure die casting magnesium alloy AE44 defect band microstructure