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Upper Bounds on List Star Chromatic Index of Sparse Graphs

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Acta Mathematica Sinica,English Series 2020年第1期36卷 1-12页

作者： Jia Ao LI Katie HORACEK Rong LUO Zheng ke miao School of Mathematical Sciences and LPMC Nankai UniversityTianjin 300071P.R.China Department of Mathematics Frostburg State UniversityFrostburgMD 21532USA Department of Mathematics West Virginia UniversityMorgantownWV 26506USA School of Mathematics and Statistics Jiangsu Normal UniversityXuzhou 221116P.R.China

A star k-edge-coloring is a proper k-edge-coloring such that every connected bicolored subgraph is a path of length at most *** star chromatic indexχ'_(st)(G)of a graph G is the smallest integer k such that G has a star *** list star chromatic index ch'st(G)is defined *** star edge coloring problem is known to be NP-complete,and it is even hard to obtain tight upper bound as it is unknown whether the star chromatic index for complete graph is linear or super *** this paper,we study,in contrast,the best linear upper bound for sparse graph *** show that for everyε>0 there exists a constant c(ε)such that if mad(G)<8/3-ε,then■and the coefficient 3/2 ofΔis the best *** proof applies a newly developed coloring extension method by assigning color sets with different sizes.

关键词： Star edge coloring list edge coloring maximum average degree

Visualization of Two-dimensional Single Chains of Hybrid Polyelectrolytes on Solid Surface

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Chinese Journal of Polymer Science 2021年第6期39卷 716-724,I0006页

作者： Lan-Lan Zhang Wen-ke miao Li-Jun Ren Yu-Kun Yan Wei Wang Center for Synthetic Soft Materials Key Laboratory of Functional Polymer Materials of the Ministry of Education and Institute of Polymer ChemistryCollege of ChemistryNankai UniversityTianjin 300071China Collaborative Innovation Center of Chemical Science and Engineering(Tianjin) Nankai UniversityTianjin 300071China

The polyacidic character of polyoxometalate(POM)clusters endows high ionic conductivity,making these clusters good candidates for solar and fuel *** bonding of clusters to polymer chains creates poly(POM)s that are polyelectrolytes with both cluster functions and polymer ***,solution-processable poly(POM)s are expected to be used as key materials in advanced *** understanding of poly(POM)s will optimize the preparation process and improve device ***,we report a study of the first linear poly(POM)s by directly visualizing the chains using scanning transmission electron *** with traditional polymers,individual clusters of poly(POM)s can be directly visualized because of the resistance to electron-beam damage and the high contrast of the tungsten POM ***,cluster aggregates with diverse shapes were *** the number of clusters in the aggregates allowed the degree of polymerization and molecular weight distribution to be determined,and studying the aggregate shapes revealed the presence of a curved semirigid chain in *** study of shape diversity revealed that strong interactions between clusters determine the diverse chain shapes formed during solution *** insight is critical to understanding the formation of poly(POM)films from solutions as key functional materials,especially for fuel and solar cells.

关键词： Polyelectrolyte Polyacidic cluster Functional hybrid Chain Scanning transmission electron microscopy

Historical biogeography and evolutionary diversification of Lilium(Liliaceae): New insights from plastome phylogenomics

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Plant Diversity 2024年第2期46卷 219-228页

作者： Nian Zhou ke miao Changkun Liu Linbo Jia Jinjin Hu Yongjiang Huang Yunheng Ji CAS key Laboratory for Plant Diversity and Biogeography of East Asia Kunming Institute of BotanyChinese Academy of SciencesKunmingYunnan 650201China University of Chinese Academy of Sciences Beijing 100049China key Laboratory of Bio-Resources and Eco-Environment of Ministry of Education College of Life SciencesSichuan UniversityChengduSichuan 610065China Yunnan key Laboratory for Integrative Conservation of Plant Species with Extremely Small Population Kunming Institute of BotanyChinese Academy of SciencesKunmingYunnan 650201China

Here, we infer the historical biogeography and evolutionary diversification of the genus Lilium. For this purpose, we used the complete plastomes of 64 currently accepted species in the genus Lilium(14plastomes were newly sequenced) to recover the phylogenetic backbone of the genus and a timecalibrated phylogenetic framework to estimate biogeographical history scenarios and evolutionary diversification rates of Lilium. Our results suggest that ancient climatic changes and geological tectonic activities jointly shaped the distribution range and drove evolutionary radiation of Lilium, including the Middle Miocene Climate Optimum(MMCO), the late Miocene global cooling, as well as the successive uplift of the Qinghai-Tibet Plateau(QTP) and the strengthening of the monsoon climate in East Asia during the late Miocene and the Pliocene. This case study suggests that the unique geological and climatic events in the Neogene of East Asia, in particular the uplift of QTP and the enhancement of monsoonal climate, may have played an essential role in formation of uneven distribution of plant diversity in the Northern Hemisphere.

关键词： Asian monsoon Climatic changes Distribution range Evolutionary complexity Radiative diversification Species diversity Qinghai-Tibet Plateau(QTP)

Congruences for a Restricted m-ary Overpartition Function

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Journal of Mathematical Research and Exposition 2010年第5期30卷 939-943页

作者： Qing Lin LU Zheng ke miao School of Mathematical Sciences Xuzhou Normal University Jiangsu 221116 P. R. China

We discuss a family of restricted m-ary overpartition functions bm,j （n）, which is the number of m-ary overpartitions of n with at most i ＋ j copies of the non-overlined part m^i allowed, and obtain a family of con... 详细信息

关键词： partition overpartition m-ary overpartition generating function.

Synthesis of a benzoxazine monomer containing maleimide and allyloxy groups

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Chinese Chemical Letters 2007年第8期18卷 973-976页

作者： Yan Tang Qing Lai Zhao ke Zeng Pei Kai miao ke Zhou Wen Rui Tang Hong Fei Zhou Tao Liu Yi Peng Wang Gang Yang State key Laboratory of Polymer Materials Engineering College of Polymer Science and Engineering Sichuan University Chengdu 610065 China

A novel benzoxazine monomer 3-（4-allyloxy）phenyl-3,4-dihydro-2H-6-（N-maleimido）-l,3-benzoxazine （AMB） was synthesized and structure was confirmed by FT-IR, 1H NMR. Thermal analysis （DSC） of AMB showed the intr... 详细信息

关键词： Benzoxazine Maleimide Allyloxy Allyl High performance polymer

Atomically dispersed calcium as solid strong base catalyst with high activity and stability

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Green Energy & Environment 2024年第10期9卷 1619-1626页

作者： Xiang-Bin Shao Zhi-Wei Xing Si-Yu Liu ke-Xin miao Shi-Chao Qi Song-Song Peng Xiao-Qin Liu Lin-Bing Sun State key Laboratory of Materials-Oriented Chemical Engineering Jiangsu National Synergetic Innovation Center for Advanced Materials(SICAM)College of Chemical EngineeringNanjing Tech University30 South Puzhu RoadNanjing211816China

Solid strong base catalysts are highly attractive for diverse reactions owing to their advantages of neglectable corrosion,facile separation,and environmental ***,their widespread applications are impeded by basic components aggregation and low *** this work,we fabricate single calcium atoms on graphene(denoted as Ca1/G)by use of a redox strategy for the first time,producing solid strong base catalyst with high activity and *** precursor Ca(NO_(3))_(2)is first reduced to CaO at 400℃ by the support graphene,forming CaO/G with conventional basic sites,and the subsequent reduction at 850℃results in the generation of Ca1/G with atomically dispersed *** characterizations reveal that Ca single atoms are anchored on graphene in tetra-coordination(Ca-C_(2)-N_(2))where N is in situ doped from Ca(NO_(3))_(2).The atomically dispersed Ca,along with their anchoring on the support,endow Ca1/G with high activity and stability toward the transesterification reaction of ethylene carbonate with *** turnover frequency value reaches 128.0 h^(-1)on Ca1/G,which is much higher than the traditional counterpart CaO/G and various reported solid strong bases(2.9-46.2 h^(-1)).Moreover,the activity of Ca1/G is well maintained during 5 cycles,while 60%of activity is lost for the conventional analogue CaO/G due to the leaching of Ca.

关键词： Solid strong base Single Ca atoms Heterogeneous catalysts Transesterification Reaction

Diffuse panbronchiolitis in China:analysis of 45 cases

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Chinese Medical Journal 2007年第22期120卷 2046-2048页

作者： DING ke LIU miao-bing WU Jin-ling MA Hui-qing FANG Xiang-yang miao Guo-bin ZHANG Lin Department of General Practice Beijing Chaoyang Hospital Capital Medical University Beijing 100020 China

Diffuse panbronchiolitis （DPB） is a relatively recently recognized, idiopathic progressive disease, originally described-in Japan in 1969. It has distinctive clinicopathological features characterized by chronic pulmonary inflammation in the respiratory bronchioles of the lung and paranasal sinuses. It has been reported more extensively among Japanese than other ethnic populations. The first case of DPB in China was reported in 1996. Since then, an increasing number of cases have been described, which suggest that this disease may not be rare in China.

关键词： diffuse panbronchiolitis macrolides

Arsenic trioxide regulates the production and activities of matrix metalloproteinases-1,-2, and -9 in fibroblasts and THP-1

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Chinese Medical Journal 2012年第24期125卷 4481-4487页

作者： LIANG Ya-hui LI Ping ZHAO Jing-xia DAI miao-ke HUANG Qi-fu Department of Pathophysiology Beijing Institute of Chinese Medicine Beijing Hospital of Chinese Medicine Capital Medical University Beijing 100010 China Beijing Rehabilitation Center Beijing 100144 China Department of Pathology School of Preclinical Medicine Beijing University of Chinese Medicine Beijing 100029 China

Background The elevated matrix metalloproteinase （MMP） activity is an important cause of chronic wound healing failure. Arsenolite, whose main component is arsenic trioxide （As203）, is a common traditional Chinese medicine wildly used in treating chronic wounds; it can remove necrotic tissue and promote tissue regeneration. This research was designed to evaluate the effects of AS2O3 on production and activities of MMP-1, MMP-2 and MMP-9, and on regulation of its signal transduction pathway in human skin fibroblasts （HSFb） and human monocyte line （THP-1 cells） that were in an inflammatory state. Methods We established three cell models; HSFb activated by TNF-α, THP-1 cells activated by phorbol 12-myristate 13-acetate （PMA） and an HSFb-THP-1 co-culture system. Three cell models was cultured with AS203 for 24 hours. The levels of MMP-1, MMP-2, MMP-9, TNF-α and IL-1β in the cell culture supernatants were assayed by ELJSA. The mRNA expressions of MMP-1, MMP-2 and MMP-9 were determined by RT-PCR. The activities of MMP-2 and MMP-9 were tested by Gelatin zymography assays. The phosphorylation levels of ERK1/2 and p38MAPK were assayed by Western blotting. Results As2O3 inhibited the expression of MMP-1, MMP-2 and MMP-9 mRNA, the secretion and activity of MMP-1, MMP-2 and MMP-9 in HSFb and THP-1 cells in the inflammatory state （P 〈0.05 and P 〈0.01 respectively）. It also inhibited the secretion of TNF-α and IL-1β in THP-1 cells and in the co-culture system （P 〈0.05 and P 〈0.01, respectively）. It also decreased the phosphorylation of ERK1/2 and p38 MAPK in HSFb and THP-1 cells （P 〈0.05 and P 〈0.01, respectively）. Conclusions AS203, as a main component of arsenolite, can inhibit the production of MMPs by HSFb and THP-1 cells in an inflammatory state through inhibiting the release of inflammatory factors and the activation of the MAPK cascade pathway. This may be a possible mechanism for arsenolite healing chronic wounds.

关键词： arsenic trioxide matrix metalloproteinase enzyme activity fibroblast THP-1

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基于耦合电感的新型高增益软开关直流变换器

电机与控制学报 2017年第8期21卷 25-32页

作者：屈克庆冯苗苗赵晋斌上海电力学院电气工程学院上海200090

针对升压直流变换器的高增益问题,以一种带有泵升电容的Boost变换器为基础,提出一种基于耦合电感的新型高增益软开关直流变换器。讨论该变换器的工作原理、性能对比分析、关键参数设计,并且通过仿真验证了理论分析的正确性。该变换器通... 详细信息

针对升压直流变换器的高增益问题,以一种带有泵升电容的Boost变换器为基础,提出一种基于耦合电感的新型高增益软开关直流变换器。讨论该变换器的工作原理、性能对比分析、关键参数设计,并且通过仿真验证了理论分析的正确性。该变换器通过引入耦合电感和倍压电容不仅拓展了调控电压增益的自由度,突破了仅由占空比来提升电压的局限,还减小了输出二极管的电压应力,且耦合电感中的漏感缓解了二极管反向恢复问题。利用有源钳位的方法减小了开关两端的应力,并使所有开关管实现软开通,使电路损耗得以降低。

关键词：升压变换器高增益耦合电感有源钳位倍压电容零电压开关