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Stochastic Comparison and Preservation of Positive Correlations for Lévy-type Processes

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Acta Mathematica Sinica,English Series 2009年第5期25卷 741-758页

作者： jie ming wang Department of Mathematics Beijing Institute of Technology Beijing 100081 P. R. China School of Mathematical Sciences and Laboratory of Mathematics and Complex Systems Beijing Normal University Beijing 100875 P. R. China

The stochastic comparison and preservation of positive correlations for Levy-type processes on R^d are studied under the condition that Levy measure v satisfies f{0〈｜z｜≤1）｜z｜｜v（x, dz） - v（x, d（-z））｜〈 ∞, x∈ R^d, while the sufficient conditions and necessary ones for them are obtained. In some cases the conditions for stochastic comparison are not only sufficient but also necessary.

关键词： stochastic comparison preservation of positive correlations Levy-type processes

Effect of Carbon Content on Stacking Fault Energy of Fe-20Mn-3Cu TWIP Steel

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Journal of Iron and Steel Research International 2014年第1期21卷 116-120页

作者： Xian PENG Ding-yi ZHU Zhen-ming HU ming-jie wang Long-long LIU Hai-jun LIU College of Materials Science and Engineering Fuzhou University Chengdu Aircraft Industrial(Group)Co. Ltd.AVIC Fujian San ming Iron and Steel Group Co. Ltd. College of Materials Science and Engineering Fujian University of Technology

The influence of carbon content on the stacking fault energy （SFE） of Fe-20Mn-3Cu twinning-induced plasticity （TWIP） steel was investigated by means of X-ray diffraction peak-shift method and thermodynamic modeling. The experimental result indicated that the stacking fault probability decreases with increasing carbon addition, the SFE increases linearly when the carbon content in mass percent is between 0.23 M and 1.41%. The thermody namic calculation results showed that the SFE varied from 22.40 to 29.64 mJ ~ m 2 when the carbon content in mass percent changes from 0.23 % to 1.41%. The XRD analysis revealed that all steels were fully austenitic before and after deformation, which suggested that TWIP effect is the predominant mechanism during the tensile deformation process of Fe-20Mn-3Cu-XC steels.

关键词： stacking fault energy carbon content peak-shift method thermodynamic modeling TWIP steel

Expression of ΔDNMT3B Variants and Its Association with Estrogen/Progestogen Receptor Status in Breast Cancer

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Chinese Journal of Cancer Research 2009年第3期21卷 229-234页

作者： Ning-hong Liu Lu Yang ming-lei Zhuo jie wang Shu-hang wang Jun Zhao Hua Bai Key Laboratory of Carcinogenesis and Translational Research （Ministry of Education） Department of Thoracic Medical Oncology Peking University School of Oncology Beijing Cancer Hospital ＆ Institute Beijing 100142 China

Objective： Our previous study has showed that △DNMT3B is the predominant form of DNMT3B in non-small cell lung cancer （NSCLC）. In this study, we aimed to explore the expression patterns of the △DNMT3B variants in breast cancer and to identify whether the pattern was similar to that in NSCLC or not and its clinical significance. Methods： Expression of seven △DNMT3B variants in 59 breast cancer and the corresponding normal tissue was measured using RT-PCR. The correlations between the expressions of △DNMT3B variants and the clinical parameters including ER/PR status, clincopathologic feature and survivals were analyzed. Results： There were significant differences in the expression ratios of △DNMT3B1-7 variants between breast cancer tissues and normal tissues （P〈0.001）. The positive ratio of △DNMT3B1-7 variants were 66%, 71%, 17%, 51%, 76.2%, 50% and 61% in tumor tissue, respectively; while 16%, 8.4%, 3.38%, 3.38%, 11.8%, 13.5% and 5.08% in the corresponding normal tissue, which was different from the pattern of △DNMT3B1-7 expression in NSCLC （62%, 76%, 2.5%, 46%, 18%, 27% and 16% in tumor tissue, respectively; while 18%, 11%, 0%, 3.3%, 0%, 0% and 0% in normal lung tissue, respectively; P〈0.0001）. Expressions of △DNMT3B2, 3B4 and 3B7 were higher in the patients with negative estrogen receptor （ER） than those with positive estrogen receptor （P=0.035, P=0.0141 and P=0.0219, respectively）. △DNMT3B7 expression was higher for the patients with negative progestogen receptor （PR） compared to those with positive progestogen receptor （P=0.0379）. Expression ratio of △DNMT3B5 in stage Ⅲ tumors is lower than that in stage Ⅰ/Ⅱ ones （P= 0.041）. But we did not find any relation between the △DNMT3B variants and the patients＇ survival. Conclusion： The pattern of △DNMT3B variants in breast cancer is different from that in NSCLC. Expressions of △DNMT3B2, 3B4 and 3B7 are associated with estrogen receptors status. While △DNMT3B7 is associated with progestogen receptor. No relation

关键词： △DNMT3B variants RT-PCR Breast cancer Estrogen receptor Progestogen receptor

Fluorescent carbon dots synthesized in solid phase and air for application in LEDs

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Nano Research 2024年第9期17卷 8495-8503页

作者： Wei-jie Zheng Zhao-Nan Sun Yi-ming wang Huan-ming Xiong Department of Chemistry and Shanghai Key Laboratory of Molecular Catalysis and Innovative Materials Fudan UniversityShanghai 200438China

Carbon dots(CDs)have been widely adopted as optical materials because of their excellent luminescent ***,most of the reported synthetic methods are conducted in solvents,especially hydrothermal/solvothermal reactions,leading to intractable problems such as toxic and flammable solvents,complex and inseparable by-products,and dangerously high pressures and ***-phase synthesis of CDs in air is an effective solution to overcome the above issues,but solid reactions always result in uncontrolled growth and agglomeration of *** this study,some inorganic salts are selected as catalysts for synthesizing CDs in solid states and air,which also play as dispersants to hinder CDs *** the meantime,some aromatic derivatives containing hydroxyl and amino groups are chosen as carbon sources,ground with the optimized catalyst,and then heated together in *** production yields are affected by the reaction time and reactant ratio,while the graphitization degrees of the CDs are determined by the reaction *** IG/ID value of their Raman spectra increases from 0.59 to 0.85,and the particle size decreases from 2.5 to 1.4 nm when the synthesis temperature is increased from 200 to 280℃.The as-prepared CDs show emission peaks ranging from 366 to 606 nm,with the photoluminescence(PL)quantum yield up to 53%.Their emission color variation mainly results from different carbon sources,which can be ascribed to the differences in the element composition,functional groups,and graphitic nitrogen content of these *** dispersing CDs of different concentrations into polyvinyl alcohol(PVA)and combining them with blue LEDs,cold,standard,and warm white light emitting devices(WLEDs)are prepared,with a color rendering index(CRI)up to *** the as-prepared CDs have antioxidant ability at high temperature,the as-prepared WLEDs have long lifespans,remaining the effective white luminescence after 72 h continuous work.

关键词： carbon dot solid-phase synthesis white LED photoluminescence inorganic salt catalysis

Visible Light-Induced[3+2]Annulation Reaction of Alkenes with Vinyl Azides:Direct Synthesis of Functionalized Pyrroles

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Chinese Journal of Chemistry 2024年第2期42卷 151-156页

作者： ming Yang Xin-Yu wang jie wang Yu-Long Zhao Jilin Province Key Laboratory of Organic Functional Molecular Design&Synthesis Faculty of ChemistryNortheast Normal UniversityChangchunJilin 130024China

A photocatalytic[3+2]annulation of alkenes with vinyl azides was developed under irradiation by visible light in the presence of organic dye *** substrate scope and high functional group tolerance were demonstrated by more than 50 *** reaction provides a novel and efficient method for the synthesis of polyfunctionalized pyrroles under very mild metal-free conditions without other additives.

关键词： Photocatalysis Vinyl azides Alkenes Pyrroles Annulation Radical reactions

Locally and globally uniform approximations for ruin probabilities of a nonstandard bidimensional risk model with subexponential claims

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Applied Mathematics(A Journal of Chinese Universities) 2024年第1期39卷 98-113页

作者： LIU Zai-ming GENG Bing-zhen wang Shi-jie School of Mathematics and Statistics Central South UniversityChangsha 410083China School of Big Data and Statistics Anhui UniversityHefei 230601China

Consider a nonstandard continuous-time bidimensional risk model with constant force of interest,in which the two classes of claims with subexponential distributions satisfy a general dependence structure and each pair of the claim-inter-arrival times is arbitrarily *** some mild conditions,we achieve a locally uniform approximation of the finite-time ruin probability for all time horizon within a finite *** we further assume that each pair of the claim-inter-arrival times is negative quadrant dependent and the two classes of claims are consistently-varying-tailed,it shows that the above obtained approximation is also globally uniform for all time horizon within an infinite interval.

关键词： bidimensional risk model asymptotic formula subexponential distribution consistently varying tail ruin probability

Topology optimization of modular structures with multiple assemblies and applications to airborne shelves

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Chinese Journal of Aeronautics 2024年第4期37卷 321-332页

作者： jie wang Tong GAO ming LI Jihong ZHU Longlong SONG Weihong ZHANG State IJR Center of Aerospace Design and Additive Manufacturing Northwestern Polytechnical UniversityXi’an 710072China Beijing Specialized Machinery Institute Beijing 100143China

This work is devoted to the aeronautical application of topology optimization for modular structures with multiple assemblies that consist of repeated standard modules and optional *** kinds of structures are widely used owing to their transportability,reconfigurability,low manufacturing and service *** this work,the design of airborne shelves with modular structures characterized by the standard module configuration is formulated for the first time as a topology optimization problem of multiple assemblies and multiple load cases subjected to the volume *** is shown that the weighted compliance design of multiple assemblies is a compromising solution compared to the optimization result of each individual assembly of standard ***,the performance of optimized airborne shelves with the modular structures can effectively be ameliorated with the help of reinforcements.

关键词： Topology optimization Modular structures Multiple assemblies Standard modules Airborne shelves

Sequential enantioselective Ugi-4CR/post-Ugi transformation strategy:a precise construction of structurally diverse azaspiro polycyclic scaffolds

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Science China Chemistry 2024年第2期67卷 576-586页

作者： Xiao-Bao Wu Jun-Xiu Shi Yi-ming Ou Hua-jie Jiang Yi-Jun Fang Qi-ming wang Quan Gao jie Yu Department of Applied Chemistry Anhui Province Engineering Laboratory for Green Pesticide Development and ApplicationAnhui Province Key Laboratory of Crop Integrated Pest ManagementAnhui Agricultural UniversityHefei230036China

A privileged strategy has been developed for the precise construction of enantioenriched azaspiro polycyclic *** diverse azaspiro polycycles bearing multiple contiguous stereocenters are obtained with excellent results(up to 99:1 e.r.,>95:5 d.r.) via sequential enantioselective four-component Ugi reactions/post-Ugi transformations with substrates containing prerequisite functional groups in the presence of anionic stereogenic-at-cobalt(Ⅲ) complexes.

关键词： asymmetric catalysis post-Ugi transformation anionic stereogenic-at-cobalt(Ⅲ)complex azaspiro polycyclic scaffold one-pot synthesis

Effect of austenitizing condition on mechanical properties,microstructure and precipitation behavior of AISI H13 steel

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Journal of Iron and Steel Research International 2024年第1期31卷 143-156页

作者： An-gang Ning Yang Liu Rui Gao Stephen Yue ming-bo wang Han-jie Guo College of Materials Science and Engineering Taiyuan University of TechnologyTaiyuan030024ShanxiChina Department of Mining and Materials Engineering McGill UniversityMontrealQCH3A 0C5Canada ASSAB Tooling Technology(Chongqing)Co. Ltd.Chongqing401120China School of Metallurgical and Ecological Engineering University of Science and Technology BeijingBeijing100083China

The effects of austenitizing temperature(1223,1303,and 1373 K)and holding time(1-1500 s)on the microstructure,mechanical properties,and precipitation behavior of the H13 hot work die steel were *** results indicate a softening phenomenon when H13 steel is austenitized at 1303 K beyond 900 s and 1373 K beyond 600 s,*** the sample held for 1200 s,the tensile strength is found capable of reaching up to 2.2 GPa when quenched from a temperature above 1303 ***,prior-austenite grain size increases with the increase in austenitizing *** kinetic behavior of the precipitates(mainly MC-type carbides)in H13 steel could be elaborated through the principles set forth by the Arrhenius and Avrami ***,the comprehensive strengthening of the H13 steel was discussed in *** results show that the activation energy of the transformed fraction of carbides is higher than that of the diffusion process for common alloying elements(Cr,V,Mo,and Ni)found in the *** suggests that it would be difficult for precipitates to dissolve into the matrix when H13 steel is austenitized at high *** the increasing austenitizing temperature,the precipitation fraction decreases,and the dislocation density *** dislocation strengthening is regarded as the dominant strengthening contributed to yield strength in as-quenched H13 steel.

关键词： H13 steel Austenitizing Mechanical property Precipitation behavior Comprehensive strengthening