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On a Problem of Potentially Pancyclic-graphic Sequences Due to S.B. Rao

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Acta Mathematicae Applicatae Sinica 2019年第2期35卷 465-474页

作者： Jian-hua YIN Department of Mathematics College of Information Science and TechnologyHainan University

A non-increasing sequenceπ=(d_1,d_2,···,d_n)of nonnegative integers is said to be potentially hamiltonian-graphic(*** pancyclic-graphic)if it is realizable by a simple graph on n vertices containing a hamiltonian cycle(*** cycles of every length from 3 to n).*** and ***(*** Ser.B,13(1972),185–191)and Kundu(Discrete Math.,6(1973),367–376)presented a characterization ofπ=(d_1,d_2,···,d_n)that is potentially ***(Lecture Notes in Math.,No.855,Springer Verlag,1981,417–440,Unsolved Problem 2)further posed the following problem:present a characterization ofπ=(d_1,d_2,···,d_n)that is potentially *** this paper,we first give solution to this problem for the case of 4≤n≤***,we also show that a near regular graphic sequenceπ=(d_1,d_2,···,d_n)with dn≥3 is potentially pancyclic-graphic.

关键词： graphic sequence potentially hamiltonian-graphic sequence potentially pancyclic-graphic sequence

Inclusion variations and calcium treatment optimization in pipeline steel production

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International Journal of Minerals,Metallurgy and Materials 2011年第5期18卷 527-534页

作者： Jian-hua Liu hua-jie Wu Yan-ping Bao Min Wang Research Institute of Metallurgy Engineering University of Science and Technology Beijing Beijing 100083 China School of Metallurgical and Ecological Engineering University of Science and Technology Beijing Beijing 100083 China

SiCa line and SiCaBaFe alloy were injected into liquid pipeline steel at the end of LF refining as calcium treatment,and samples were taken from the ladles,mould,and *** of Ca content and inclusions shows that Ca content in steel decreases obviously in the following process after calcium treatment;the compositions,morphology,and sizes of inclusions also vary much in the production;primary inclusions in the ladles prior to calcium treatment are mainly Al2O3 inclusions,but they turn to fine irregular CaS-CaO-Al2O3 compound inclusions after the treatment,then become fine globular CaO-Al2O3 inclusions in the mould,and finally change to a few larger irregular CaS-CaO-Al2O3 complex inclusions in the *** study reveals that inclusion variations are related with the preferential reactions among Ca,Al2O3,and S and the precipitation of S in CaO-Al2O3 inclusions with high sulfur *** evaluation standards for calcium treatment in high-grade pipeline steel were put forward according to the inclusion variations and requirements of pipeline steel on inclusion controlling,and the calcium process was studied and optimized.

关键词： pipeline steel refining inclusions calcium treatment thermodynamics precipitation

Output Feedback H~∞ Control for a Class of Nonlinear Stochastic Systems

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Acta Mathematicae Applicatae Sinica 2010年第2期26卷 251-266页

作者： Yuan-hua Ni Key Laboratory of Systems and Control Institute of Systems Science Academy of Mathematics and SystemsScience Chinese Academy of Sciences Beijing 100190 China

This paper deals with the output feedback H∞ control problem for a class of nonlinear stochastic systems. Based on the latest developed theory of stochastic dissipation, a notable result about the nonlinear H∞ output feedback control of deterministic system is generalized to the stochastic case. Finally, in the cases of state feedback and output feedback, two families of controllers are provided respectively.

关键词： H∞ control stochastic nonlinear systems Hamilton-Jacobi-Isaacs equations output feedback

Basic Soil Productivity of Spring Maize in Black Soil Under Long-Term Fertilization Based on DSSAT Model

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Journal of Integrative Agriculture 2014年第3期13卷 577-587页

作者： ZHA Yan WU Xue-ping he Xin-hua ZHANG Hui-min GONG Fu-fei CAI Dian-xiong ZHU Ping GAO Hong-jun Key Laboratory of Crop Nutrition and Fertilization Ministry of Agricultural/Institute of Agricultural Resources and Regional Planning Chinese Academy of Agricultural Sciences School of Plant Biology University of Western Australia Jilin Academy of Agricultural Sciences

Increasing basic farmland soil productivity has significance in reducing fertilizer application and maintaining high yield of crops. In this study, we defined that the basic soil productivity （BSP） is the production capacity of a farmland soil with its own physical and chemical properties for a specific crop season under local environment and field management. Based on 22-yr （1990-2011） long-term experimental data on black soil （Typic hapludoll） in Gongzhuling, Jilin Province, Northeast China, the decision support system for an agro-technology transfer （DSSAT）-CERES-Maize model was applied to simulate the yield by BSP of spring maize （Zea mays L.） to examine the effects of long-term fertilization on changes of BSP and explore the mechanisms of BSP increasing. Five treatments were examined：（1） no-fertilization control （control）; （2） chemical nitrogen, phosphorus, and potassium （NPK）; （3） NPK plus farmyard manure （NPKM）; （4） 1.5 time of NPKM （1.5NPKM） and （5） NPK plus straw （NPKS）. Results showed that after 22-yr fertilization, the yield by BSP of spring maize significantly increased 78.0, 101.2, and 69.4% under the NPKM, 1.5NPKM and NPKS, respectively, compared to the initial value （in 1992）, but not significant under NPK （26.9% increase） and the control （8.9% decrease）. The contribution percentage of BSP showed a significant rising trend （P〈0.05） under 1.5NPKM. The average contribution percentage of BSP among fertilizations ranged from 74.4 to 84.7%, and ranked as 1.5NPKM〉NPKM〉NPK〉NPKS, indicating that organic manure combined with chemical fertilizers （I.5NPKM and NPKM） could more effectively increase BSP compared with the inorganic fertilizer application alone （NPK） in the black soil. This study showed that soil organic matter （SOM） was the key factor among various fertility factors that could affect BSP in the black soil, and total N, total P and/or available P also played important role in BSP increasing. Compared with the chemical fertilization, a balanced chem

关键词： spring maize long-term fertilization basic soil productivity black soil DSSAT model

Short-range disorder in MOF glasses

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National Science Review 2021年第5期8卷 13-14页

作者： Ming-hua Zeng Key Laboratory for the Chemistry and Molecular Engineering of Medicinal Resources School of Chemistry and Pharmaceutical SciencesGuangxi Normal University Hubei Collaborative Innovation Center for Advanced Organic Chemical Materials Ministry of Education Key Laboratory for the Synthesis and Application of Organic Functional MoleculesHubei University

Glass appears to be an ordinary material with wide applications in daily life and industry; however, its formation mechanism, phase transition and microscopic structure remain mysterious. It is accepted to be an amorphous solid exhibiting glass transition, with short-range(20?A)disorder structures [1]. Experimental determination of the structure of glass is crucial to understand its dynamic and physical properties.‘What is the nature of glass?’ is one of the most fundamental and challenging scientific questions [1].

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Modeling the Potential Geographic Distribution of Black Pepper(Piper nigrum)in Asia Using GIS Tools

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Journal of Integrative Agriculture 2012年第4期11卷 593-599页

作者： HAO Chao-yun FAN Rui Milton Cezar Ribeiro TAN Le-he WU hua-song YANG Jian-feng ZheNG Wei-quan YU huan Spice and Beverage Research Institute Chinese Academy of Tropical Agricultural Sciences/Key Laboratory of Genetic Resources Utilization of Spice and Beverage Crops Ministry of Agriculture/Hainan Provincial Key Laboratory of Genetic Improvement and Quality Regulation for Tropical Spice and Beverage Crops Wanning 571533 P.R.China Ecological Departament University of Sao Paulo Sao Paulo 05513-970 S.P.Brazil

Known as the ＂king of spices＂,black pepper（Piper nigrum）,a perennial crop of the tropics,is economically the most important and the most widely used spice crop in the *** understand its suitable bioclimatic distribution,maximum entropy based on ecological niche modeling was used to model the bioclimatic niches of the species in its Asian *** on known occurrences,bioclimatic areas with higher probabilities are mainly located in the eastern and western coasts of the Indian Peninsula,the east of Sumatra Island,some areas in the Malay Archipelago,and the southeast coastal areas of *** undocumented places were also predicted as suitable *** to the jackknife procedure,the minimum temperature of the coldest month,the mean monthly temperature range,and the precipitation of the wettest month were identified as highly effective factors in the distribution of black pepper and could possibly account for the crop＇s distribution *** climatic requirements inhibited this species from dispersing and gaining a larger geographical range.

关键词： Piper ngirum ENM bioclimatic distribution Maxent

Cytosolic phospholipase A2α modulates cell-matrix adhesion via the FAK/paxillin pathway in hepatocellular carcinoma

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Cancer Biology & Medicine 2019年第2期16卷 377-390页

作者： Piao Guo Yuchao he Lu Chen Lisha Qi Dongming Liu Ziye Chen Manyu Xiao Liwei Chen Yi Luo Ning Zhang hua Guo Department of Tumor Cell Biology Department of hepatobiliary Cancer Department of Pathology Tianjin Medical University Cancer Institute and Hospital National Clinical Research Center for Cancer/ Key Laboratory of Cancer Prevention and Therapy Tianjin Tianjin's Clinical Research Center for Cancer Tianjin 300060 China

Objective: To explore the effect of cytosolic phospholipase A2α(cPLA2α) on hepatocellular carcinoma(HCC) cell adhesion and the underlying ***: Cell adhesion, detachment, and hanging-drop assays were utilized to examine the effect of cPLA2α on the cell-matrix and cell-cell adhesion. Downstream substrates and effectors of cPLA2α were screened via a phospho-antibody *** signaling pathways were identified by the functional annotation tool DAVID. Candidate proteins were verified using Western blot and colocalization was investigated via immunofluorescence. Western blot and immunohistochemistry were used to detect protein expression in HCC tissues. Prognosis evaluation was conducted using Kaplan-Meier and Cox-proportional hazards regression ***: Our findings showed that cPLA2α knockdown decreases cell-matrix adhesion but increases cell-cell adhesion in hepG2 cells. Microarray analysis revealed that phosphorylation of multiple proteins at specific sites were regulated by cPLA2α. These phosphorylated proteins were involved in various biological processes. In addition, our results indicated that the focal adhesion pathway was highly enriched in the cPLA2α-relevant signaling pathway. Furthermore, cPLA2α was found to elevate phosphorylation levels of FAK and paxillin, two crucial components of focal adhesion. Moreover, localization of p-FAK to focal adhesions in the plasma membrane was significantly reduced with the downregulation of cPLA2α. Clinically, cPLA2α expression was positively correlated with p-FAK levels. Additionally, high expression of both cPLA2α and p-FAK predicted the worst prognoses for HCC ***: Our study indicated that cPLA2α may promote cell-matrix adhesion via the FAK/paxillin pathway, which partly explains the malignant cPLA2α phenotype seen in HCC.

关键词： hepatocellular carcinoma cytosolic phospholipase A2α cell-matrix adhesion FAK paxillin

A Conjecture Concerning the Pure Exponential Diophantine Equation a^x+b^y=c^z

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Acta Mathematica Sinica,English Series 2005年第4期21卷 943-948页

作者： Mao hua LE Department of Mathematics Zhanjiang Normal College Zhanfiang 524005 P. R. China

Let a, b, c, r be fixed positive integers such that a^2 ＋ b^2 = c^r, min（a, b, c, r）〉 1 and 2 r. In this paper we prove that if a ≡ 2 （mod 4）, b ≡ 3 （mod 4）, c 〉 3.10^37 and r 〉 7200, then the equation a... 详细信息

关键词： Pure exponential diophantine equation Number of solutions Completely determine

Synthesis and mechanism of environmentally friendly high temperature and high salt resistant lubricants

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Petroleum Science 2023年第5期20卷 3110-3118页

作者： Zong-Lun Wang Jin-Sheng Sun Jing-Ping Liu Kai-he Lv Zi-hua Shao Xian-Fa Zhang Zhe Xu Zhi-Wen Dai Ning huang School of Petroleum Engineering China University of Petroleum(East China)Qingdao 266580ShandongChina CNPC Engineering Technology R&D Company Limited Beijing 102206China

With the exploration and development of deep and ultra-deep oil and gas,high torque and high friction during the drilling of deep and ultra-deep wells become one of the key issues affecting drilling safety and drilling ***,the high temperature and high salt problem in deep formations is prominent,which poses a major challenge to the lubricity of drilling fluids under high temperature and high *** paper reports an organic borate ester SOP as an environmentally friendly drilling fluid *** performance evaluation results show that when 1%lubricant SOP is added to the fresh water-based mud,the lubrication coefficient decreases from 0.631 to 0.046,and the reduction rate of lubrication coefficient is 92.7%.Under the conditions of 210℃ and 30%NaCl,the reduction rate of lubricating coefficient of the base slurry with 1%SOP was still remain 81.5%.After adding 1%SOP,the wear volume decreased by 94.11%compared with the base *** contact resistance experiment during the friction process shows that SOP can form a thick adsorption film on the friction surface under high temperature and high salt conditions,thus effectively reducing the friction *** dynamics simulation shows that lubricant SOP can be physically adsorbed on the surface of drilling tool and borehole wall through hydrogen bond and van der Waals *** analysis further shows that SOP adsorbs on the friction surface and reacts with metal atoms on the friction surface to form a chemically reactive ***,under high temperature and high salt conditions,the synergistic effect of physical adsorption film and chemical reaction film effectively reduces the frictional resistance and wear of the friction *** addition,SOP is non-toxic and easy to ***,SOP is a highly effective and environmentally friendly lubricant in high temperature and high salt drilling fluid.

关键词： Deep oil and gas Lubricant Environmentally friendly Water-based drilling fluid Molecular dynamics simulations