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Discussions on Orthogonal Factorizations in Digraphs

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Acta Mathematicae Applicatae Sinica 2022年第2期38卷 417-425页

作者： Si-zhong ZHOU hong-xia LIU School of Science Jiangsu University of Science and TechnologyZhenjiang 212100China School of Mathematics and Information Sciences Yantai UniversityYantai 264005China

Let m,t,r and k_(i)(1≤i≤m)be positive integers with k_(i)≥(t+3)r/2,and G be a digraph with vertex set V(G)and arc set E(G).Let H_(1),H_(2),…,H_(t) be t vertex-disjoint subdigraphs of G with mr *** this article,it is verified that every[0,k_(1)+k_(2)+…+k_(m)-(m-1)r]-digraph G has a[0,k_(i)]_(1)^(m)-factorization r-orthogonal to every H_(i) for 1≤i≤t.

关键词： network digraph factor factorization orthogonal factorization

Synthesis of Tritium and Deuterium Labelled Agmatine

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Chinese Chemical Letters 2006年第5期17卷 587-590页

作者： hong xia HE Zhi Bing ZHENG Lan Fu CHEN Zhan Bin ZHANG chun HU Song LI Shenyang Pharmaceutical University Shenyang 110016 Beijing Institute of Pharmacology and Toxicology Beijing 100850 Beijing Normal University Beijing 100875

An efficient procedure for the synthesis of agmatine labelled with tritium and deuterium is reported. The final tritiated product 4 was obtained with a specific activity of 40 Ci/mmol and a radiochemical purity of 95%.

关键词： Agmatine labelled compound synthesis deuterium tritium.

Scheme for Implementing Quantum Dense Coding and Teleportation with Tripartite Entangled State in Cavity QED

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Communications in Theoretical Physics 2008年第11期50卷 1113-1116页

作者： JIA chun-xia PENG Zhao-Hui Department of Physics Hunan University of Science and Technology Xiangtan 411201 China

In this paper, we present a peculiar tripartite entangled state that is inequivalent to both the GHZ state and the W state, and then propose to implement efficient quantum information processing such as quantum dense coding and teleportation with this entangled state in cavity QED. In this scheme the atoms interact with a highly detuned cavity field with the assistance of a strong classical driven field. It does not require the transfer of quantum information between the atomic system and the cavity, and then our scheme is insensitive to both the cavity decay and the thermal field.

关键词： dense coding teleportation cavity QED

Electrochemical Study and Application on Shikonin at Poly（diallyldimethylammonium chloride） Functionalized Graphene Sheets Modified Glass Carbon Electrode

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Chemical Research in Chinese Universities 2013年第4期29卷 798-805页

作者： AN Jing LI Ji-ping CHEN Wen-xia YANG chun-xia HU Fang-di WANG chun-ming School of Pharmacy Hospital of Lanzhou University College of Chemistry and Chemical Engineering Lanzhou University Lanzhou 730000 P. R. China

The electrochemical behaviors of shikonin at a poly（diallyldimethylammonium chloride） functionalized graphene sheets modified glass carbon electrode（PDDA-GS/GCE） have been investigated. Shikonin could exhibit a pair of well-defined redox peaks at the PDDA-GS/GCE located at 0.681 V（Epa） and 0.662 V（Epc）[vs. saturated calo- mel electrode（SCE）] in 0.1 mol/L phosphate buffer solution（pH=2.0） with a peak-to-peak separation of about 20 mV, revealing a fast electron-transfer process. Moreover, the current response was remarkably increased at PDDA- GS/GCE compared with that at the bare GCE. The electrochemical behaviors of shikonin at the modified electrode were investigated. And the results indicate that the reaction involves the transfer of two electrons, accompanied by two protons and the electrochemical process is a diffusional-controlled electrode process. The electrochemical para- meters of shikonin at the modified electrode, the electron-transfer coefficient（a）, the electron-transfer number（n） and the electrode reaction rate constant（ks） were calculated to be as 0.53, 2.18 and 3.6 s^-1, respectively. Under the optimal conditions, the peak current of differential pulse voltammetry（DPV） increased linearly with the shikonin concentra- tion in a range from 9A72×10^-8 mol/L to 3,789×10^-6 mol/L with a detection limit of 3,157× 10^-8 mol/L. The linear regression equation was Ip=O.7366c＋0.7855（R=0.9978; lp： 10-7 A, c： 10-8 mol/L）. In addition, the modified glass carbon electrode also exhibited good stability, selectivity and acceptable reproducibility that could be used for the sensitive, simple and rapid determination of shikonin in real samples. Therefore, the present work offers a new way to broaden the analytical application of graphene in pharmaceutical analysis.

关键词： Shikonin Poly(diallyldimethylammonium chloride) functionalized graphene sheets modified glass carbon electrode(PDDA-GS/GCE) Cyclic voltammetry Differential pulse voltammetry Electrochemical sensor

Ar adsorptions on Al (111) and Ir (111) surfaces:a first-principles study

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Chinese Physics B 2012年第2期21卷 437-444页

作者： Niu Wen-xia Zhang hong Institution of Atomic and Molecular Physics Sichuan UniversityChengdu 610065China College of Physical Science and Technology Sichuan UniversityChengdu 610065China

We investigate the adsorptions of Ar on Al （111） and Ir （111） surfaces at the four high symmetry sites, i.e., top, bridge, fcc- and hcp-hollow sites at the coverage of 0.25 monolayer （ML） using the density functional theory within the generalized gradient approximation of Perdew, Burke and Ernzerhof functions. The geometric structures, the binding energies, the electronic properties of argon atoms adsorbed on Al （111） and Ir （111） surfaces, the difference in electron density between on the Al （111） surface and on the Ir （111） surface and the total density of states are calculated. Our studies indicate that the most stable adsorption site of Ar on the Al （111） surface is found to be the fcc-hollow site for the （2 x 2） structure. The corresponding binding energy of an argon atom at this site is 0.538 eV/Ar atom at a coverage of 0.25 ML. For the Ar adsorption on Ir （111） surface at the same coverage, the most favourable site is the hcp-hollow site, with a corresponding binding energy of 0.493 eV. The total density of states （TDOS） is analysed for Ar adsorption on Al （111） surface and it is concluded that the adsorption behaviour is dominated by the interaction between 3s, 3p orbits of Ar atom and the 3p orbit of the base Al metal and the formation of sp hybrid orbital. For Ar adsorption on Ir （111） surface, the conclusion is that the main interaction in the process of Ar adsorption on Ir （111） surface comes from the 3s and 3p orbits of argon atom and 5d orbit of Ir atom.

关键词： density-functional theory binding energy adsorption electronic structure

Synthesis and characterization of star-comb styrene/butadiene copolymer

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Chinese Chemical Letters 2010年第11期21卷 1370-1373页

作者： Qing Min Zhang Chuang Chen hong xia Zhang chun Qing Zhang Yang Li Xi Gao Jian State Key Laboratory of Fine Chemicals Department of Polymer Science and Engineering School of Chemical Engineering Dalian University of Technology Dalian 116012 China Liaoning Province Key Laboratory of Polymer Science and Engineering Dalian 116012 China

A novel star-comb styrene/butadiene copolymer（SC-SBC） was synthesized by anionic polymerization and grafting reaction with epoxidized star liquid polybutadiene（ESPB） as coupling *** overall shape of the star-comb macromolecules can be altered by changing the molecular weight and number of the side *** molecular parameters and mechanical properties of the SC-SBC resins were *** notched izod impact strength of the SC-SBC resins are excellent and reach as high as to 239 J/m.

关键词： Anionic polymerization Epoxidation Grafting reaction Star-comb copolymer Side chain

Constitutive model of disturbed soil-structure interface within mining subsidence areas

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Journal of Central South University 2017年第7期24卷 1676-1683页

作者： CHANG hong xia Jun-wu Mechanics and Civil Engineering China University of Mining&TechnologyXuzhou 221116China Key Laboratory of Deep Coal Resources Mining of Ministry of Education(China University of Mining&Technology) Xuzhou 221116China

The characteristics of a disturbed soil-structure interface were studied based on the variation regularities of the disturbed soil within its mining subsidence area using direct shear *** effects of the initial moisture content on the shear strength parameters of the soil-structure interfaces were *** results indicate that the cohesion of the interface initially increased and then decreased as the initial moisture content *** addition,the friction angle of the interface decreased as the initial moisture content increased.A constitutive model of the disturbed soil-structure interface,a rigid-plastic model based on the initial void ratio and saturability(VSRP) model,was established based on the *** order to validate this model,a finite element analysis of DRS-1 direct shear tests was *** finite element model calculations coincided with the results of the DRS-1 direct shear *** proposed model also reflected the nonlinear features of the soil-structure interface.

关键词： mining subsidence areas soil-structure interface rigid-plastic model finite element method

Co-occurrence of IPMN and malignant IPNB complicated by a pancreatobiliary fistula: A case report and review of the literature

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World Journal of Clinical Cases 2019年第1期7卷 102-108页

作者： Xu Ren chun-Lan Zhu Xu-Fu Qin hong Jiang Tian xia Yong-Ping Qu Digestive Disease Hospital of Heilongjiang Provincial Hospital The Second Digestive Department Digestive Disease Hospital of Heilongjiang Provincial Hospital Department of Pathology of Heilongjiang Provincial Hospital Digestive Endoscopy Center Digestive Disease Hospital of Heilongjiang Provincial Hospital

BACKGROUND Intraductal papillary neoplasm of the bile duct(IPNB) is pathologically similar to intraductal papillary mucinous neoplasm(IPMN). However, there are several significant differences between them. The rate of IPMN associated with extrapancreatic malignancies has been reported to range from 10%-40%, and it may occasionally be complicated with the presence of fistulas. IPMN associated with malignant IPNB is extremely rare and only nine cases have been reported in the *** SUMMARY We report a 52-year-old man who presented with recurrent cholangitis for nine months. Computed tomography and magnetic resonance cholangiopancreatography showed the common bile duct stricture with dilated pancreatobiliary duct without other abnormal findings. The underlying pathogenesis could not be identified based on the radiologic images. Endoscopic retrograde cholangiopancreatography revealed a pancreatobiliary fistula with dilated main pancreatic duct, biliary stricture with dilated biliary tree, and mucus discharge from the enlarged orifice of the major papilla. The patient underwent SpyGlass cholangiopancreatoscopy due to a suspected mucin-producing biliary neoplasm and indeterminate main pancreatic duct dilatation. Multiple papillary growing neoplasms with vascular images, with the extent of lesions spreading in the biliopancreatic ductal lumens, were identified by SpyGlass. In addition, the presence of a pancreatobiliary fistula was also identified. The patient was diagnosed as having benign IPMN and malignant IPNB with focal invasion by postoperative pathology. Furthermore, varying histological subtypes were present in both IPMN and IPNB. Pylorus-preserving pancreaticoduodenectomy was performed on the patient with excellent results during the 52 month followup *** We deemed that pancreatography and SpyGlass allowed for an efficient diagnosis of IPMN with pancreatobiliary fistula, whereas the etiology could not be identified by radiologic imaging.

关键词： Intraductal papillary mucinous neoplasm of the pancreas Intraductal papillary neoplasm of the bile duct Extrapancreatic malignancies Co-occurrence Pancreatobiliary fistula SpyGlass cholangiopancreatoscopy Endoscopic retrograde cholangiopancreatography Case report

Human impact recorded in the sediment of honghu Lake, Hubei, China

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Journal of Environmental Sciences 2006年第2期18卷 402-406页

作者： YAO Shu-chun XUE Bin xia Wei-lan Nanjing Institute of Geography and Limnology Chinese Academy of Sciences Nanjing 210008 China Graduate School of CAS Beijing 100039 China

Vertical profiles of the total organic carbon （TOC）, total nitrogen （TN）, phosphorus, susceptibilities, elements and partical size were analyzed in a short ^137Cs-dated sediment core collected from honghu Lake, China. The average sedimentation rate was 1.55 mm/a. The results indicated that trophic status of honghu Lake in the historical period had experienced three stages. Before 1840 the lake was characterized with lower productivity, TOC was less than 9.92 g/kg; TN was 0.902 to 1.24 g/kg. During about 1840-1950, population increased quickly, there was an obvious change in TOC with an average of 13.0 g/kg. Since 1950, human impacts have accelerated the lake eutrophication and nutrients enriched in the sediment with TOC of 21.7 to 93.1 g/kg, TN of 1.77 to 8.78 g/kg. The heavy metal concentration profiles presented similar distribution trends except Pb .and Mn. The results from elements analyses indicated that honghu Lake had not been polluted by heavy metals except lead.

关键词： honghu Lake lake deposit human impact