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Plasma Science and Technology 2010年第5期12卷 608-613页

作者： i.y.y.bu A.J.FLEWiTT W.i.MiLiNE Department of Microelectronics Engineering National Kaohsiung Marine University Electrical Engineering Division Engineering Department Cambridge University

Deposition of nanocrystalline silicon （nc-Si） on glass at very low temperatures by electron cyclotron resonance （ECR） plasma enhanced chemical vapour deposition （PECVD） was investigated. it was shown that nc-Si could be deposited from hydrogen diluted silane gas at a substrate temperature of 80℃ with a crystalline fraction up to 80% and a lateral grain size of around 50 nm. This was achieved by growing the nc-Si in a low pressure regime which ensured that mono-silyl species were the dominant deposition precursor. Furthermore, a high flux of energetic hydrogen ions was required to induce crystallisation of the silicon material through a chemical annealing process.

关键词： low temperature nanocrystalline silicon ECR

Control of dislocation density maximizing precipitation strengthening effect

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Journal of Materials Science & Technology 2022年第32期127卷 133-143页

作者： C.Xu W.J.Dai y.Chen Z.X.Qi G.Zheng y.D.Cao J.P.Zhang C.C.bu G.Chen MiiT Key Laboratory of Advanced Metallic and internetallic Materials Technology Engineering Research Center of Materials Behavior and DesignMinistry of EducationNanjing University of Science and TechnologyNanjing 210094China

The strength-ductility trade-off has been the most challenging problem for structural metals for *** strengthening is an ideal approach to enhance the strength without significantly sacrificing the *** nanoprecipitates have been successfully acquired by nanostructural design,but the number density of nanoprecipitates cannot be further *** attempted to enhance number density by introducing highly potent nucleation sites(e.g.,dislocations).However,there remains controversy over the influence of dislocations on the nucleation and growth of coherent nanoprecipitates with minimized nucleation ***,Cu-rich nanoprecipitates in an HSLA steel,as a typical type of coherent nanoprecipitates,are *** combining analytical calculation and experiments,we show that dislocations are harmful for the formation of large numbered Cu-rich nanoprecipitates in a certain density *** dislocations deprive solute atoms which decrease homogenous precipitation that cannot be compensated by the increase in heterogeneous *** such circumstance,Cu-rich nanoprecipitates have smaller number density but larger size and higher fraction of incoherent structures due to rapid Ostwald *** a result,by controlling dislocation density,the yield strength is increased by 24%without obvious loss in ductility as compared with traditional solution-quench-age *** work would help to optimize composition and processing routes that fully exploit the nanoprecipitation strengthening effect.

关键词： Cu-rich nanoprecipitates Crystallographic defects Nucleation Structural transformation Ostwald ripening

Oxidative stress and lipid peroxidation products:effect of pinealectomy or exogenous melatonin injections on biomarkers of tissue damage during acute pancreatitis

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Hepatobiliary & Pancreatic Diseases international 2010年第1期9卷 78-82页

作者： Cavit l Kahraman Dinler O■uz Hasdemir Oktay Büyüka■ik Güler bu■dayci Department of General Surgery Abant Izzet Baysal University Medical School Department of Biochemistry Abant Izzet Baysal University Medical School

BACKGROUND:Melatonin (N-acetyl-5-methoxytripta-mine) is a free radical scavenger and a strong antioxidant,secreted by the pineal *** this study,we evaluated the effects of decreasing and increasing serum melatonin levels on malonyldialdehyde (MDA),superoxide dismutase (SOD),and reduced glutathione (GSH) levels in pancreatic tissue from rats with experimental acute ***:Experimental acute pancreatitis was induced in three groups of Wistar albino rats (10 animals per group) by pancreatic ductal *** first group had only acute pancreatitis and served as the *** pinealectomy was added to acute pancreatitis in the second group,removing the source of endogenous melatonin (low melatonin levels group).The third group was given 0.1 ml daily intraperitoneal injections of 20 mg/ml melatonin solution for one week (high melatonin levels group).The effects of melatonin levels were evaluated by comparison of the levels of MDA,SOD,and GS in pancreatic ***:We found that intraperitoneal melatonin injections decreased the levels of MDA and increased the levels of SOD and GSH in pancreatic ***:Exogenous melatonin has a preventive effect on lipid peroxidation and oxidative damage in acute pancreatitis.

关键词： pineal gland acute pancreatitis melatonin oxidative damage

Operator-Valued Fourier Multipliers on Multi-dimensional Hardy Spaces

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Chinese Annals of Mathematics,Series B 2011年第2期32卷 293-302页

作者： Shangquan bu Department of Mathematical Sciences Tsinghua University Beijing 100084 China

The author establishes operator-valued Fourier multiplier theorems on multi-dimensional Hardy spaces Hp(Td;X),where 1 ≤ p < ∞,d ∈ N,and X is an AUMD Banach space having the property (α).The suffcient condition on ... 详细信息

The author establishes operator-valued Fourier multiplier theorems on multi-dimensional Hardy spaces Hp(Td;X),where 1 ≤ p is an AUMD Banach space having the property (α).The suffcient condition on the multiplier is a Marcinkiewicz type condition of order 2 using Rademacher boundedness of sets of bounded linear *** is also shown that the assumption that X has the property (α) is necessary when d ≥ 2 even for scalar-valued *** the underlying Banach space does not have the property (α),a suffcient condition on the multiplier of Marcinkiewicz type of order 2 using a notion of d-Rademacher boundedness is also given.

关键词： H~p-Spaces Fourier multiplier Rademacher boundedness d-Rademacher boundedness

DOES iNVESTOR SENTiMENT PREDiCT STOCK RETURNS? THE EViDENCE FROM CHiNESE STOCK MARKET

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Journal of Systems Science & Complexity 2014年第1期27卷 130-143页

作者： bu Hui Pi Li School of Economics and Management Beihang University

This paper examines the proxy variables of investor sentiment in Chinese stock market carefully, and tries to construct an investor sentiment index indirectly. We use cross correlation analysis to examine lead-lag relationship between the proxy variables and HS300 index. The results show that net added accounts （NAA）, SSE share turnover （TURN）, and closed-end fund discount （CEFD） are leading variables to stock market. The average first day return of iPOs （RiPO） and relative degree of active trading in equity market （RDAT） are contemporary variables, while number of iPOs （NiPO） is a lagging variable of stock market. Using the sentiment proxy variables with most possible leading order, and forward selection stepwise regression method, the empirical results on monthly stock returns reveal that three leading proxy variables can be used to form a sentiment index. And the out of sample tests prove that this sentiment index has good predictive power of Chinese stock market, and it is robust.

关键词： Chinese stock market investor sentiment return predictability.

Spectral and Timing Analysis of the Black Hole Transient MAXi J1631–479 During its 2019 Outburst Observed with insight-HXMT

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Research in Astronomy and Astrophysics 2022年第11期22卷 21-33页

作者： yu-Cong Fu L.M.Song G.Q.Ding S.N.Zhang J.L.Qu S.Zhang L.Zhang Q.C.bu y.Huang X.Ma Z.X.yang y.L.Tuo X.F.Lu D.K.Zhou B.y.Wu T.M.Li y.C.Xu Xinjiang Astronomical Observatory Chinese Academy of SciencesUrumqiXinjiang 830011China University of Chinese Academy of Sciences Chinese Academy of SciencesBeijing 100049China Key Laboratory of Particle Astrophysics Institute of High Energy PhysicsChinese Academy of SciencesBeijing 100049China institut fur Astronomie und Astrophysik Kepler Center for Astro and Particle PhysicsEberhard Karls UniversitatSand 1D-72076 TübingenGermany

We report spectral and timing analysis of the black hole transient MAXi J1631–479 during the hard intermediate state of its 2019 outburst from the insight-Hard X-ray Modulation Telescope(insight-HXMT)*** find that the energy dependence of the type-C quasi-periodic oscillation(QPO)frequency evolves with time:during the initial rise of a small flare(~MJD 58526.0-58527.1),the QPO frequency increases with increasing energy from~1 to~100 ke V,and then the frequency remains constant after MJD *** discover a possible new phenomenon of Fe line’s QPO frequency jump that has never been observed for other black hole transients:during the small flare,the QPO frequency around the Fe line energy is higher than any other energy band,with the frequency difference Δf=0.25±0.08 Hz between 5.5–7.5 ke V and other energy *** spectral analysis shows that the evolution of QPOs is related to the equivalent width of the narrow Fe line,and its equivalent width increases during this small *** propose that the QPO frequency difference results from the differential precession of a vertically extended jet,and the higher QPO frequency of Fe line could be caused by the layered jet when the jet scale *** the same time,the evolution of QPOs is related to the accretion rate,while the energy dependence of QPOs supports the existence of deceleration in the vertically distributed jet.

关键词： accretion accretion disks stars:black holes X-rays:binaries

Molecular epidemiological study of animal rabies in Kazakhstan

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Journal of integrative Agriculture 2023年第4期22卷 1266-1275页

作者： Gulzhan N.yESSEMBEKOVA XiAO Shuang Assem ABENOV Talgat KARiBAEV Alexandr SHEVTSOV Amirgazin ASyLULAN yersyn y.MUKHANBETKALiyEV SHUAi Lei bu Zhi-gao Sarsenbay K.ABDRAKHMANOV S.Seifullin Kazakh Agro Technical University Nur-Sultan 010011Kazakhstan State Key Laboratory for Animal Disease Control and Prevention Harbin Veterinary Research InstituteChinese Academy of Agricultural SciencesHarbin 150069P.R.China National Reference Center for Veterinary Medicine Center for BiotechnologyNur-Sultan 010000Kazakhstan National Center for Biotechnology Nur-Sultan 010000Kazakhstan

Rabies is a serious public health issue in Kazakhstan, with high economic impact and social burden. As part of a routine surveillance, 31 rabies-positive brain specimens taken from livestock(cattle) and carnivores(dogs, foxes, and cats)during 2013–2021 were subject to viral sequencing. Phylogenetic and Bayesian analysis were performed using obtained rabies virus(RABV) sequences. All 31 strains of RABV candidate belonged to the Cosmopolitan clade, of which 30strains belonged to steppe-type subclade, and 1 dog strain belonged to Other subclade. The 31 strains did not diverge from RABV strains in Kazakhstan and neighboring countries, including Russia, Mongolia, and China, suggesting that animal rabies has close relationship and transmission between borders. Fox-originated strains and cattle strains shared similar sequence signature, and some animal rabies cases had space–time intersection, showing that infected foxes were a major transmission source of cattle rabies in different Kazakhstan regions. Besides, free-roaming dogs played a pivotal role in rabies epizootics of cattle in Kazakhstan. The recent spread of animal rabies presents an increasing threat to public health, and provides updated information for improving current control and prevention strategies at the source for Kazakhstan and neighboring countries.

关键词： rabies livestock carnivores phylogenetic analysis

Some Properties of the injective Tensor Product of Banach Spaces

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Acta Mathematica Sinica,English Series 2007年第9期23卷 1697-1706页

作者： Xiao Ping XUE yong Jin Li Qing ying bu(Qingying bu) Department of Mathematics Harbin Institute of Technology Harbin 150001 P. R. China Department of Mathematics Sun Yat-sen University Guangzhou 510275 P. R. China Department of Mathematics University of Mississippi University MS 38677 USA

Let X and y be Banach spaces such that X has an unconditional basis. Then X y, the injective tensor product of X and y, has the Radon-Nikodym property （respectively, the analytic Radon-Nikodym property, the near Radon-Nikodym property, non-containment of a copy of co, weakly sequential completeness） if and only if both X and y have the same property and each continuous linear operator from the predual of X to y is compact.

关键词： tensor products types of Radon-Nikodym properties Schauder decomposition

k-fold coloring of planar graphs

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Science China Mathematics 2010年第10期53卷 2791-2800页

作者： GuanFeng Ren yueHua bu Zhejiang Normal Univ Dept Math Jinhua 321004 Peoples R China

A k-fold n-coloring of G is a mapping φ: V (G) → Zk(n) where Zk(n) is the collection of all ksubsets of {1,2,...,n} such that φ(u) ∩φ(v) = φ if uv ∈ E(G).if G has a k-fold n-coloring,i.e.,G is k-fold *** the smallest integer n such that G is k-fold n-colorable be the k-th chromatic number,denoted by χk(G).in this paper,we show that any outerplanar graph is k-fold 2k-colorable or k-fold χk(C*)-colorable,where C* is a shortest odd cycle of ***,we investigate that every planar graph with odd girth at least 10k-9(k 3) can be k-fold (2k + 1)-colorable.

关键词： k-fold coloring planar graph the shortest odd cycle

Solutions of second order degenerate integro-differential equations in vector-valued function spaces

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Science China Mathematics 2013年第5期56卷 1059-1072页

作者： bu ShangQuan CAi Gang Department of Mathematical Sciences Tsinghua University

We study the well-posedness of the second order degenerate integro-differential equations （P2）：（Mu）t＇（t）＋ a（Mu）＇（t） = Au（t）＋ ft_c~ a（t - s）Au（s）ds ＋ f（t）, 0 ≤ t ≤ 27r, with periodic boundary conditions Mu（O） = Mu（27r）, （Mu）＇（O） = （Mu）＇（2π）, in periodic Lebesgue-Bochner spaces LP（T,X）, periodic Besov spaces BBp,q（T, X） and periodic Triebel-Lizorkin spaces F~,q（＇F, X）, where A and M are closed linear operators on a Banach space X satisfying D（A） C D（M）, a C Li（R＋） and a is a scalar number. Using known operator- valued Fourier multiplier theorems, we completely characterize the well-posedness of （P2） in the above three function spaces.

关键词： Fourier multiplier degenerate integro-differential equation well-posedness Besov spaces Triebel- Lizorkin spaces