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Some Class 1 Graphs on gc-colorings

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Acta mathematica Sinica,English Series 2016年第10期32卷 1237-1245页

作者： hua Wen ma Xia ZHANG School of mathematical Sciences Shandong Normal UniversityJi'nan 250014P·R·China

An edge-coloring of a graph G is an coloring of a graph G is an edge-coloring of G such assignment of colors to all the edges of G. A go- that each color appears at each vertex at least g（v） times. The maximum integer k such that G has a go-coloring with k colors is called the gc-chromatic index of G and denoted by X＇gc （G）. In this paper, we extend a result on edge-covering coloring of Zhang X＇gc（） = δg（G）, and Liu in 2011, and give a new sufficient condition for a simple graph G to satisfy ＇ x＇gc（G）=δg（G）,where δg（G）=minv∈V（G）{[d（v）/g（v）]}.

关键词： Edge-coloring go-coloring go-chromatic index edge covering classification problem

Effects of land-use types on soil organic carbon stocks:a case study across an altitudinal gradient within a farmpastoral area on the eastern Qinghai-Tibetan Plateau, China

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Journal of Mountain Science 2018年第12期15卷 2693-2702页

作者： WANG Fang-ping WANG xin-chuan YAO Bu-qing ZHANG Zhong-hua SHI Guo-xi ma Zhen CHEN Zhi ZHOU hua-kun College of Ecological and Environmental Engineering State Key Laboratory of Plateau Ecology and AgricultureQinghai UniversityXining 810015China Key Laboratory of Restoration Ecology of Cold Area in Qinghai Province Northwest Institute of Plateau BiologyChinese Academy of SciencesXining 810008China Key Laboratory of Adaptation and Evolution of Plateau Biota Chinese Academy of SciencesXining 810008China Farm of Good Forage Grass Breeding in Qinghai Province Tongde 813201China College of Bioengineering and Biotechnology Tianshui Normal UniversityTianshui 741000China Key Laboratory of Medicinal Animal and Plant in Qinghai-Tibetun Plateau in Qinghai Province Qinghai Normal UniversityXining 810008China University of Chinese Academy of Sciences Beijing 100o49China

A crucial region for China's ‘Grain-forGreen Policy' is located within a traditional farmpastoral area, between 2000 to 3000 m above sea level, on the eastern Qinghai-Tibetan ***, the responses of soil organic carbon(SOC) to different land-use patterns in this region are unclear. Here, we determined the SOC(0–20 cm) content of grasslands and forests that are being converted from farmlands, as well as in abandoned arable land and arable land in this region. The factors influencing the reclaimed lands were analyzed along altitudes from 2030 to 3132 m. Our results showed that SOC content was higher for grassland and abandoned arable land than forest and arable land. The SOC content increased with the increase in altitude for total land-use patterns. Further, the grassland and abandoned arable land had higher SOC content than the forest with almost parallel trends along the increase in altitude. However, the proportion of regulated factors of altitude and species richness varied among forest, grassland, and abandoned arable land. Our results indicated that the land-use pattern of returning farmland to grassland and abandoned arable land was more effective in terms of the SOC storage in the superficial layer in this altitude range in the Qinghai-Tibetan Plateau, thereby being beneficial to optimizing land management in this region.

关键词： Soil organic carbon Grain for Green program Farming land Qinghai-Tibetan Plateau

Analysis of retained austenite in TRIP590 steel by electron backscattered diffraction method

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Journal of Iron and Steel Research International 2020年第3期27卷 355-365页

作者： Yu-cheng Zhang Yang Meng Gui-bin Cui Hui-ping Jia xin-hua Ju Zhong-hang Jiang Ze-jun ma Bruker(Beijing)Scientific Technology Co. Ltd.Beijing 100192.China Research Institute of Technology Shougang Group Co.Ltd.Beijing 100043China

The retained austenite content in TRIP590 steel was first measured by X-ray diffraction(XRD)***,the effect of different test parameters(indexing rate,step size,field number,etc.)on the measured results of retained austenite content in TRIP590 steel by electron backscattered diffraction(EBSD)method was *** comparing the measured results between XRD and EBSD method,the optimal test parameters for the analysis of retained austenite content using EBSD were ***,the total content of retained austenite and the retained austenite contents with different aspect ratios in TRIP590 steel were analyzed,*** results showed that the test parameters have a great influence on the measured results of retained austenite content in TRIP590 *** order to improve the test accuracy,high indexing rates,small step sizes and more field number are necessary for the analysis of retained austenite content in TRIP590 steel by EBSD method.

关键词： TRIP590 steel Retained austenite Electron backscattered diffraction Indexing rate Step size

Lipidomic investigation of the protective effects of Polygonum perfoliatum against chemical liver injury in mice

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Journal of Integrative Medicine 2023年第3期21卷 289-301页

作者： Lei Peng hua-guo Chen xin Zhou Key Laboratory for Information System of Mountainous Areas and Protection of Ecological Environment Guizhou Normal UniversityGuiyang 550001Guizhou ProvinceChina Guizhou Engineering Laboratory for Quality Control&Evaluation Technology of Medicine Guizhou Normal UniversityGuiyang 550001Guizhou ProvinceChina Research Center for Quality Control of Natural Medicine Guizhou Normal UniversityGuiyang 550001Guizhou ProvinceChina

Objective:Recent investigations have demonstrated that Polygonum perfoliatum *** protect against chemical liver injury,but the mechanism behind its efficacy is still ***,we studied the pharmacological mechanism at work in *** protection against chemical liver ***:To evaluate the activity of *** against chemical liver injury,levels of alanine transaminase,lactic dehydrogenase,aspartate transaminase,superoxide dismutase,glutathione peroxidase and malondialdehyde were measured,alongside histological assessments of the liver,heart and kidney tissue.A nontargeted lipidomics strategy based on ultra-performance liquid chromatography quadrupoleorbitrap high-resolution mass spectrometry method was used to obtain the lipid profiles of mice with chemical liver injury and following treatment with ***;these profiles were used to understand the possible mechanisms behind ***'s protective ***:Lipidomic studies indicated that *** protected against chemical liver injury,and the results were consistent between histological and physiological *** comparing the profiles of liver lipids in model and control mice,we found that the levels of 89 lipids were significantly *** animals receiving *** treatment,the levels of 8 lipids were significantly improved,relative to the model *** results showed that *** extract could effectively reverse the chemical liver injury and significantly improve the abnormal liver lipid metabolism of mice with chemical liver injury,especially glycerophospholipid ***:Regulation of enzyme activity related to the glycerophospholipid metabolism pathway may be involved in the mechanism of ***'s protection against liver injury.

关键词： Lipidomics Polygonum perfoliatum L. Liver injury Mice Herbal medicine

Core-satellite metal-organic framework@upconversion nanoparticle superstructures via electrostatic self-assembly for efficient photodynamic theranostics

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Nano Research 2020年第12期13卷 3377-3386页

作者： Zhike Li Xi Qiao Guihua He xin Sun Danhua Feng Liefeng Hu hua Xu Hai-Bing Xu Shengqian ma Jian Tian Key Laboratory of Combinatorial Biosynthesis and Drug Discovery Hubei Province Engineering and Technology Research Center for Fluorinated PharmaceuticalsSchool of Pharmaceutical SciencesWuhan UniversityWuhan430071China State Key Laboratory of Bioelectronics School of Biological Science and Medical EngineeringSoutheast UniversityNanjing210096China Ministry-of-Education Key Laboratory for the Synthesis and Application of Organic Functional Molecules Hubei Collaborative Innovation Center for Advanced Organic Chemical MaterialsCollege of Chemistry and Chemical EngineeringHubei UniversityWuhan430062China Department of Chemistry University of North TexasDentonTX76201USA

The nanoplatforms based on upconversion nanoparticles(UCNPs)have shown great promise in amplified photodynamic therapy(PDT)triggered by near-infrared(NIR)***,their practical in vivo applications are hindered by the overheating effect of 980 nm excitation and low utilization of upconversion luminescence(UCL)by *** solve these defects,core-satellite metal-organic framework@UCNP superstructures,composed of a single metal-organic framework(MOF)NP as the core and Nd3+-sensitized UCNPs as the satellites,are designed and synthesized via a facile electrostatic self-assembly *** superstructures realize a high co-loading capacity of chlorin e6(Ce6)and rose bengal(RB)benefitted from the highly porous nature of MOF NPs,showing a strong spectral overlap between maximum absorption of photosensitizers and emission of *** in vitro and in vivo experiments demonstrate that the dual-photosensitizer superstructures have trimodal(magnetic resonance(MR)/UCL/fluorescence(FL))imaging functions and excellent antitumor effectiveness of PDT at 808 nm NIR light excitation,avoiding the laser irradiation-induced overheating *** study provides new insights for the development of highly efficient PDT nanodrugs toward precision theranostics.

关键词： core-satellite structures upconversion nanoparticles(UCNPs) nanoscale metal-organic frameworks photodynamic therapy theranostics

Spring-back deformation in tube bending

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International Journal of Minerals,Metallurgy and materials 2009年第2期16卷 177-183页

作者： Da-xin E hua-hui He Xiao-yi Liu Ru-xin Ning School of materials Science and Engineering Beijing Institute of Technology Beijing 100081 China

The spring-back of a bending metal tube was studied through extensive experiments and finite element method （FEM） analysis. An approximate equation for the spring-back angle of bending was deduced. It is noted that the mechanical properties of the material （in a tubular form） are quite different from those found in the standard tensile tests （when the materials are in bar forms）. This is one of the major reasons that result in the discrepancies in the outcomes of experimental study, FEM calculations, and spring-back analysis. It is therefore of crucial importance to study the mechanical properties of the materials in their tubular forms. The experiments and FEM simulations prove that the spring-back angle is significantly affected by the mechanical properties of the materials. The angle decreases accordingly with plastic modulus, but changes inversely with the hardening index and elastic modulus The spring-back angle is also affected by the conditions of tube deformation： it increases accordingly with the relative bending radius but changes inversely with the relative wall thickness. In addition, the spring-back angle increases nonlinearly with the bending angle.

关键词： tube bending spring-back finite element simulation tensile test

A VERTICAL 2D maTHEmaTICAL MODEL FOR HYDRODYNAMIC FLOWS WITH FREE SURFACE IN σ COORDINATE

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Journal of Hydrodynamics 2006年第1期18卷 82-90页

作者： ZHANG Jing-xin LIU hua XUE Lei-ping School of Naval Architecture Ocean and Civil Engineering Shanghai Jiaotong University Shanghai 200030 China

Numerical models with hydrostatic pressure have been widely utilized in studying flows in rivers, estuaries and coastal areas. The hydrostatic assumption is valid for the large-scale surface flows where the vertical acceleration can be ignored, but for some particular cases the hydrodynamic pressure is important. In this paper, a vertical 2t） mathematical model with non-hydrostatic pressure was implemented in the σ coordinate. A fractional step method was used to enable the pressure to be decomposed into hydrostatic and hydrodynamic components and the predictor-corrector approach was applied to integration in time domain. Finally, several computational cases were studied to validate the importance of contributions of the hydrodynamic pressure.

关键词： vertical 2D model free surface flow semiimplicit non-hydrostatic

Dechlorination mechanism of 2,4-dichlorophenol by Ni/Fe nanoparticles in the presence of humic acid

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2009年第1期10卷 121-126页

作者： Jing-jing WO Zhen ZHANG xin-hua XU Department of Environmental Engineering Zhejiang University Hangzhou 310027 China School of Bioscience Taizhou University Linhai 317000 China

To understand the feasibility of its application to the in situ remediation of contaminated groundwater,the dechlori-nation of 2,4-dichlorophenol (2,4-DCP) by Ni/Fe nanoparticles in the presence of humic acid (HA) was *** found that,as high performance liquid chromatography (HPLC) was used,the 2,4-DCP was first quickly reduced to o-chlorophenol (o-CP) and p-chlorophenol (p-CP),and then reduced to phenol as the final *** experimental results indicated that HA had an adverse effect on the dechlorination of 2,4-DCP by Ni/Fe nanoparticles,as the HA concentration increased,the removal rate decreased *** also demonstrated that 2,4-DCP was reduced more easily to o-CP than to p-CP,and that the sequence of the tendency in dechlorination of intermediates was p-CP>*** electron microscope (TEM) showed that HA could act as an adsorbate to compete reactive sites on the surface of Ni/Fe nanoparticles to decrease the dechlorination *** we con-cluded that the dechlorination reaction of 2,4-DCP over Ni/Fe nanoparticles progressed through catalytic reductive dechlorination.

关键词： Dechlorination Ni/Fe nanoparticles 2 4-dichlorophenol (2 4-DCP) Humic acid (HA)

Progress on pollen-stigma compatibility in Corylus (hazelnuts): a review

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Journal of Forestry Research 2013年第3期24卷 397-402页

作者： ma Qing-hua WANG Gui-xi LIANG Wei-jian CHEN xin LIANG Li-song ZHAO Tian-tian Research Institute of Forestry Chinese Academy of Forestry / State Key Laboratory of Tree Genetics and Breeding Liaoning Institute of Economic Forestry

The genus Corylus is an important member in the Betulaceae family of the order Fagales. Self-incompatibility is one of the choke points in breeding and hazelnut production. This reviewe describes, the progress on pollen-stigma compatibility in Corylus, including basic re- productive characteristics, S-alleles testing and their applications, in- ter-specific hybridization, self-compatibility in wild species, and recent molecular research on the genetic mechanism of compatibility. Com- pared with other species, progress on pollen-stigma compatibility （sporophytic self-incompatibility, SSI） in Corylus is slow, especially those in the Brassicaceae family. De novo approaches should be used to target the unique reproductive characteristics of hazelnuts. The continu- ous improvement of technological platforms based on molecular biology should broaden the pathways in investigating compatibility in Corylus. In addition, research should be conducted on overcoming self- and cross- incompatibility, and approaches based on biological, chemical, and physical principles should be introduced. Both theoretical and practical study of compatibility in Corylus should be devoted to change the self-incompatibility trait into a benefit in the species evolvement and nut quality establishment.

关键词： SSI S-locus basic mechanism breeding pollination