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An algorithm for decomposing a polynomial system into normal ascending sets

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Science China Mathematics 2007年第10期50卷 1441-1450页

作者： Ding-kang WANG yan ZHANG Key Laboratory of Mathematics Mechanization Academy of Mathematics and Systems Science Chinese Academy of Sciences Beijing 100080 China Key Laboratory of Mathematics Mechanization Academy of Mathematics and Systems Science Chinese Academy of Sciences Beijing 100080 China

We present an algorithm to decompose a polynomial system into a finite set of normal ascending sets such that the set of the zeros of the polynomial system is the union of the sets of the regular zeros of the normal ascending sets. If the polynomial system is zero dimensional, the set of the zeros of the polynomials is the union of the sets of the zeros of the normal ascending sets.

关键词： zero decomposition, normal ascending set, polynomial system

Curvature Dependence of Interfacial Properties for Associating Lennard-Jones Fluids:A Density Functional Study

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Chinese Physics Letters 2011年第2期28卷 168-171页

作者： SUN Zong-Li kang yan-Shuang Science and Technology College North China Electric Power UniversityBaoding 071051 College of Science Agriculture University of HebeiBaoding 071001

Classical density functional theory is used to study the associating Lennard Jones fluids in contact with spherical hard wall of different curvature *** interfacial properties including contact density and fluid-solid intcrfacial tension are *** influences of associating energy,curvature of hard wall and the hulk density of fluids on these properties are analyzed in *** results may provide helpful clues to understand the interfacial properties of other complex fluids.

关键词： curvature interfacial spherical

Influence of Re-Ti modification on the high impact wear resistance of high Si bainitic cast steel

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International Journal of Minerals,Metallurgy and Materials 2010年第6期17卷 756-762页

作者： Jin-feng Huang Hong-sheng Fang yan-kang Zheng State Key Laboratory for Advanced Metals and Materials University of Science and Technology Beijing Beijnig 100083 China Department of Materials Science and Engineering Tsinghna University Beijing 100084 China

The effect of rare earth （Re） and titanium （Ti） multi-modification on the impact wear behavior of Mn-B high-Si bainitic cast steel was investigated systematically. The experiments show that the impact wear resistance can be improved greatly with the addition of Re and Ti. Its wear loss is only about 1/3-1/2 as large as that of the unmodified bainitic cast steel. By the Re/Ti modification, coarse dendrite grains and bainitic/martensite duplex structure have been refined effectively, and the impact toughness of the bainitic cast steel is nearly tripled （10 mm×10 mm×55 mm, with unnotched sample）. Consequently, the modified bainitic cast steel possesses good wear resistance under high im- pact. For both modified and unmodified bainitic cast steels, high hardness white layer and deformed zone are developed beneath the worn surface under the high impact wear, but the formation and propagation of cracks are different for these bainitic casting steels. Different mod- els for the formation and propagation of cracks for both modified and unmodified bainitic cast steels under high impact wear are proposed.

关键词： cast steel modification grain refmement impact wear spalling

Influence of metallurgical processing parameters on defects in cold-rolled steel sheet caused by inclusions

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International Journal of Minerals,Metallurgy and Materials 2019年第4期26卷 440-446页

作者： Rui Wang yan-ping Bao Yi-hong Li Zhi-jie yan Da-zhao Li yan kang School of Materials Science and Engineering North University of China State Key Laboratory of Advanced Metallurgy University of Science and Technology Beijing School of Materials Science and Engineering Taiyuan University of Science and Technology

The cleanliness and defects for cold-rolled steel sheet caused by inclusions are greatly influenced by parameters in the metallurgical processing. Good control of parameters during the processing can lead to a better product. In this paper, data mining was used to explore the influence of parameters on defects in steel sheets. A decision tree model was established and it was found that the oxygen content before deoxidation, the end-point temperature of the converter, and the temperature before deoxidation had a great impact on the defects in the cold-rolled sheet that were caused by inclusions. This finding was confirmed by experiments with infrared absorption, scanning electron microscopy(SEM), energy dispersive X-ray spectroscopy(EDS), and automatic inclusion analysis methods. After optimization according to results from the model and experiments, the defect rate caused by the inclusions was reduced from 0.92% to 0.38%.

关键词： IF steel steel cleanliness data mining inclusions

Synthesis,Crystal Structure and Its Application in Living Cells Imaging of Benz(c)acridine-1,2,3-triazole Derivatives

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Chinese Journal of Structural Chemistry 2021年第10期40卷 1309-1316页

作者： yan Zhen-Shuo kang yan-Hui CHEN yang-Ling HUO Li-Ni Guangxi University of Chinese Medicine Nanning 530001China Hebei University of Engineering Handan 056038China

A highly selective iron ions fluorescent probe based on the benz(c)acridine-1,2,3-triazole derivatives was produced by multi-step reactions. 1-(7-Benz[c]acridinyl)-4-(4-methylphenyl)-1,2,3-triazole(4 a), C_(26)H_(18)N_(4), was structurally determined by single-crystal X-ray diffraction. It crystallizes in the trigonal system, space group R-3 with a = 36.230(10), b = 36.230(10), c = 7.993(3)Å, β = 90°, V = 9086(6)Å^(3), Z = 18, D_(c)= 1.271 g/cm^(3), F(000) = 3636, μ = 0.602 mm^(-1), the final R = 0.0865 and wR = 0.1619 for 3951 observed reflections(I > 2σ(I)). X-ray analysis indicated that all four rings of benz(c)acridine are in the same plane, and the 1,2,3-triazole ring and the corresponding linked benzene(C(1)–C(6)–C(7)–C(8)–C(9)–N(1)) are approximately perpendicular with a dihedral angle of 106.5°. The crystal packing of the compound was stabilized by two weak interactions between C(11)–H(10)…N(4) and C(18)–H(18)…N(1). In fluorescence spectra studies, compound 4 c was exhibited good selectivity and sensitivity towards iron ions in DMSO: mops buffer solution. Furthermore, 4 c was successfully used for imaging iron ions in living He La cervical cancer cells.

关键词： benz(c)acridine-1 2 3-triazole crystal structure fluorescent probe iron ions

The Uniqueness of the Entire Functions Whose n-th Powers Share a Small Function with Their Derivatives

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Acta Mathematica Sinica,English Series 2014年第5期30卷 785-792页

作者： Jie ZHANG Hai yan kang Liang Wen LIAO College of Science China University of Mining and Technology Department of Mathematics Nanjing University

In this paper, we prove the following result： Let f（z） be a transcendental entire function, Q（z） ≡ 0 be a small function of f（z）, and n ≥ 2 be a positive integer. If fn（z） and（fn（z）） share Q（z） CM, then f（z） = ce 1 nz, where c is a nonzero constant. This result extends Lv＇s result from the case of polynomial to small entire function.

关键词： Uniqueness entire function share values small function

Application of CD34 expression combined with three-phase dynamic contrast-enhanced computed tomography scanning in preoperative staging of gastric cancer

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World Journal of Gastrointestinal Surgery 2023年第11期15卷 2513-2524页

作者： Hua Liu kang-yan Zhao Department of Pathology The First People's Hospital of LianyungangLianyungang 222000Jiangsu ProvinceChina Department of Radiology Xiangyang Central HospitalAffiliated Hospital of Hubei University of Arts and SciencesXiangyang 441021Hubei ProvinceChina

BACKGROUND Accurate preoperative staging of gastric cancer(GC),a common malignant tumor worldwide,is critical for appropriate treatment plans and *** three-phase enhanced computed tomography(CT)scanning for preoperative staging of GC has limitations in evaluating tumor ***34,a marker on vascular endothelial cell surfaces,is promising in evaluating tumor *** explored the value of their combination for preoperative staging of GC to improve the efficacy and prognosis of patients with *** records of 106 patients with GC treated at the First People's Hospital of Lianyungang between February 2021 and January 2023 were retrospectively *** patients underwent three-phase dynamic contrast-enhanced CT scanning before surgery,and CD34 was detected in gastroscopic biopsy *** surgical and pathological results as the gold standard,the diagnostic results of three-phase dynamic contrast-enhanced CT scanning at different T and N stages were analyzed,and the expression of CD34-marked microvessel density(MVD)at different T and N stages was *** specificity and sensitivity of three-phase dynamic contrast-enhanced CT and CD34 in T and N staging were calculated;those of the combined diagnosis of the two were evaluated in *** factors affecting lymph node metastasis were analyzed using multiple logistic *** The accuracy of three-phase dynamic contrast-enhanced CT scanning in diagnosing stages T1,T2,T3 and T4 were 68.00%,75.00%,79.41%,and 73.68%,respectively,and for diagnosing stages N0,N1,N2,and N3 were 75.68%,74.07%,85.00%,and 77.27%,***34-marked MVD expression increased with increasing T and N *** and sensitivity of three-phase dynamic contrast-enhanced CT in T staging were 86.79%and 88.68%;for N staging,89.06%and 92.86%;for CD34 in T staging,64.15%and 88.68%;and for CD34 in N staging,84.38%and 78.57%,*** and sensitivity of joint diagno

关键词： CD34 Three-phase dynamic contrast-enhanced computed tomography scanning Gastric cancer Preoperative staging Invasion Lymph node metastasis

Brain structural plasticity in rats subjected to early binocular enucleation characterized by high resolution anatomical magnetic resonance imaging and diffusion tensor imaging

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Magnetic Resonance Letters 2023年第1期3卷 14-21,I0002页

作者： Xuxia Wang Fuchun Lin yan kang Hao Lei Center for Brain Science State Key Laboratory of Magnetic Resonance and Atomic and Molecular PhysicsNational Center for Magnetic Resonance in WuhanKey Laboratory of Magnetic Resonance in Biological SystemsInnovation Academy for Precision Measurement Science and TechnologyChinese Academy of SciencesWuhan430071China

Visual deprivation leads to structural neuroplasticity in the blind subjects,including gray matter(GM)and white matter(WM)atrophy and alterations in structural *** rat model of binocular enucleation(BE)is a frequently used animal model for studying brain plasticity induced by early *** few neuroimaging studies have been performed on this model to investigate whether or not the BE rats have image phenotypes similar to or comparable to,those observed in the early blind *** current study aimed to assess brain structural plasticity in BE rats using anatomical magnetic resonance imaging(MRI)and diffusion tensor imaging(DTI).The results demonstrated that early BE at postnatal day 4(P4)caused almost complete degeneration of optic nerve(ON)and optic chiasma(OCH),atrophy in a number of visual and non-visual structures,including optic tract(OT),dorsal lateral geniculate nucleus(DLG)and corpus callosum(CC).The BE rats also exhibited impairments of WM microstructural integrity in the OT,and reduction of structural connectivity between the normal-appearing visual cortex(VC)and somatosensory/motor cortices at 4 months of age,likely as manifestations of deafferentationinduced *** structural neuroplasticity in BE rats observable to structural MRI parallels largely with what has been reported in blind subjects,suggesting that longitudinal neuroimaging studies on animal models of sensory deprivation can provide insights into how the brain changes its wiring and function during development/adaption in response to the lack of sensory stimuli.

关键词： Blindness Brain Structural plasticity MRI Rats

Microstructure and mechanical properties of F_(GBA)/B_G air cooling bainitic steels containing niobium

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International Journal of Minerals,Metallurgy and Materials 2010年第4期17卷 429-434页

作者： Chun Feng Hong-sheng Fang Bing-zhe Bai yan-kang Zheng Department of Materials Science and Engineering Tsinghua University Beijing 100084 China

The effect of different Nb additions on the mechanical properties and microstrucmre evolution of grain boundary allotriomorphic ferrite （FGBA） / granular bainite （BG） air cooling bainitic steels was investigated. The results indicate that the tensile strength and yield strength increase by 157 and 97 MPa, respectively with the addition of 0.02wt% Nb. The steel acquires superior strength and toughness with the addition of 0.06wt% Nb. The results of scanning electron microscopy and transmission electron microscopy reveal that the addition of Nb not only refines the size of granular bainite but also increases the volume fraction of granular bainite in FGBA/BG steels. The refinement effect of granular bainite is improved with the increase of Nb content.

关键词： granular bainite microstructure evolution mechanical properties Nb