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The change of Morin transition temperature in nanocrystalline α-Fe_2O_3

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Chinese science Bulletin 1997年第4期42卷 344-346页

作者： LI Haibo, GONG Jie, ZHENG Weitao, CHEN Gang and YU Ruihuang1. Department of Materials science, Jilin university, changchun 130023, china 2 Department of Physics, Siping normal ( lege, Siping 136000, china Department of Materials science Jilin University Changchun China Department of Physics Siping Normal College Siping China

THE magnetic property of the ultrafine particles differs from that ot the bulk materials and has a lot of applications. Because of the size effect, magnetically ordered materials exhibit both superparamagnetism and collective magnetic excitation, and the magnetic transition temperature changes in the ultrafine particles with respect to the bulk materials as well. Bulk α-Fe2O3 is weakly ferromagnetic above the Morin transition temperature TM

关键词： Morin transition ultrafine particles Mossbauer effect.

Coexistence of two sympatric and morphologically similar bat species Rhinolophus a nis and Rhinolophus pearsoni

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Progress in Natural science:Materials International 2008年第5期18卷 523-532页

作者： Tinglei Jiang, Jiang Feng , Keping Sun, Jing Wang College of Urban and Environmental sciences, Northeast normal university, changchun 130024, china College of Urban and Environmental sciences Northeast Normal University Changchun 130024 China

Ecologists have long focused on the coexistence of sympatric species. Here, we investigated two horseshoe bat species, Rhinolophus a nis and Rhinolophus pearsoni inhabited in the same cave, for their foraging strategies, niche di erentiation, prey selection, and their coexistence status. These two species of horseshoe bats were di erent in the dominant frequency of their echolocation calls, but similar in their morphology. We found evidence for prey selectivity although there was a high degree of overlap in prey categories and sizes. R. a nis and R. pearsoni foraged on 16 and 7 categories insects, respectively, with Pyralidae, Geometridae, Melolonthidae dominating their diets. The degree of trophic niche overlap was 0.69. Pairwise comparisons suggested that there was no obvious di erentiation in prey categories and size. However, high prey availability in the environment (Simpson diversity index = 0.79 and Margalef richness index = 4.12) contributed to their coexistence by dampening the interspeci c competition. Since there are one or more mechanisms facil- itating species coexistence in a community, our results suggest that the spatial niche di erentiation in foraging microhabitats and in for- aging habitats at landscape scale may promote the coexistence of the two bat species. However, additional eld data are needed to con rm this speculation.

关键词： Bats Species coexistence Foraging strategies Niche di erentiation Prey richness

Engagement of PSGL-1 enhances β2-integrin-involved adhesion of neutrophils to recombinant ICAM-1

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Acta Pharmacologica Sinica 2006年第5期27卷 617-622页

作者： Xiao-guang WANG~(2,3) Yan-ping CHENG~4 Xue-qing BA~(2,5) ~2Institute of Genetics and Cytology Northeast normal university,changchun 130024,china:~3Department of Biology,changchun normal College,changchun 13.03.,china ~4College of life science.Jilin normal university,Siping 136001,china Institute of Genetics and Cytology Northeast Normal University Changchun 130024 China Department of Biology Changchun Normal College Changchun 130032 China College of life science Jilin Normal University Siping 136001 China

Aim:The interactions of selectins and their ligands initiate the process of leuko-cyte migrating into inflamed tissue.P-selectin glycoprotein ligand 1 （PSGL-1） isthe best characterized ligand of selectins,and has been demonstrated to mediatethe adhesion of leukocytes to all three selectins in ***-1 not only func-tions as an anchor molecule to capture the leukocytes to the activated endothelialcells by its interaction with selectins,but also transduces the signals to *** present work aimed to investigate the mechanism by whichPSGL-1-mediated signal activates neutrophils and enhances the adhesion to theendothelial ***:We detected the effects of the engagement of PSGL-1with monoclonal antibodies （mAb） or P-selectin on the adhesion of neutrophils tothe recombinant intercellular adhesion molecule-1 （ICAM-1）,and on the expres-sion of β***,the role of cytoskeleton in these process wasstudied by using inhibitor cytochalasin ***:The engagement of PSGL-Iincreased the expression of β2-integrin on the surface of neutrophils and en-hanced the adhesion of neutrophils to the recombinant *** againstCD18 impaired the adhesion of PSGL-1-engaged neutrophils to ***,the inhibitor cytochalasin B largely blocked the increase of CD 18 expression aswell as the adhesion of PSGL-1-engaged neutrophils to ***:The PSGL-1-transduced signals can enhance β2-integrin-involved adhesion ofneutrophils to the recombinant ICAM-1,and this process depends on the dynam-ics of cytoskeleton.

关键词： P-selectin ligand protein intercellular signaling peptides and proteins intercellular adhesion molecule-1 CD 18 antigens

Exact Solutions to Maccari's System

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Communications in Theoretical Physics 2007年第7期48卷 7-10页

作者： PAN Jun-Ting GONG Lun-Xun school of science,Guizhou normal university,Guiyang 550001,china school of science Guizhou Normal University

Based on the generalized Riccati relation,an algebraic method to construct a series of exact solutionsto nonlinear evolution equations is *** concise and straightforward,the method is applied to Maccari'ssystem,and some exact solutions of the system are *** method is of important significance in exploring exactsolutions for other nonlinear evolution equations.

关键词： generalized Riccati relation Maccari’s system exact solution

Recent advances in metabolic engineering of microorganisms for production of tyrosol and its derivatives

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生物工程学报 2024年第8期40卷 2604-2625页

作者： LIU Yingjie FU changchun ZHANG Xuepeng GU Bixuan HU Haitao YANG Ruijin LYU Xiaomei school of Food science and Technology Jiangnan UniversityWuxi 214122JiangsuChina

Tyrosol is a natural phenolic compound with antioxidant,anti-inflammatory and other biological activities,serving as an important precursor of high-value products such as hydroxytyrosol and ***,the green and efficient biosynthesis of tyrosol and its derivatives has become a research hotspot in recent *** cell factories by metabolic engineering of microorganisms is a potential industrial production way,which has low costs and environmental *** paper introduces the biosynthesis pathway of tyrosol and presents the key regulated nodes in the de novo synthesis of tyrosol in Escherichia coli and Saccharomyces *** addition,this paper reviews the recent advances in metabolic engineering for the production of hydroxytyrosol and *** review can provide a reference for engineering the strains for the high-yield production of tyrosol and its derivatives.

关键词： tyrosol metabolic engineering Escherichia coli Saccharomyces cerevisiae hydroxytyrosol salidroside

Manifold contraction for semi-supervised classification

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science china(Information sciences) 2010年第6期53卷 1170-1187页

作者： HU EnLiang 1,2 , CHEN SongCan 1 & YIN XueSong 1 1 school of Computer science & Engineering, Nanjing university of Aeronautics & Astronautics, Nanjing 210016, china 2 school of Mathematics, Yunnan normal university, Kunming 650092, china 1. school of Computer science & Engineering Nanjing University of Aeronautics & Astronautics Nanjing 210016 China2. School of Mathematics Yunnan Normal University Kunming 650092 China

The generalization ability of classification is often closely related to both the intra-class compactness and the inter-class *** to the fact that many current dimensionality reduction methods, regarded as a pre-processor, often lead to the poor classification performance on real-life data, in this paper, a new data preprocessing technique called manifold contraction(MC) is proposed for the classification-oriented learning *** main motivation behind MC lies in seeking a proper mapping of contracting the given multiple-manifold data such that the ratio of the intra-class to the inter-class scatters is ***, in order to properly control the contraction level in MC, an adaptive MC(AMC) criterion is developed in the semi-supervised *** to its generality, MC can be not only applied in original space and reproducing kernel Hilbert space(RKHS), but also easily incorporated with dimensionality reduction method for further improvement of classification *** final experimental results show that MC, as a data preprocessor, is effective and promising in the subsequent classification learning, especially in small-size labeled sample case.

关键词： manifold learning dimensionality reduction lower-dimensional embedding semi-supervised learning classification manifold contraction adaptive manifold contraction

A new calculation method for the number of radial slots of a Terfenol rod

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science china(Technological sciences) 2009年第2期52卷 336-338页

作者： HE XiPing1 & ZHANG Pin2 1 Applied Acoustics Institute, Shaanxi normal university, Xi’an 710062, china 2 school of science, Xi’an university of Architecture and Technology, Xi’an 710055, china 1. Applied Acoustics Institute Shaanxi Normal University Xi’an 710062 China 2. school of science Xi’an University of Architecture and Technology Xi’an 710055 China

Terfenol is an ideal choice for medium to high power low frequency sonar. It can offer the transducer designer higher strain, higher power density, but the designer must be aware of the eddy current. To enhance efficiency of the barrel-stave transducer powered by a Terfenol rod, radial slots rather than laminations were used to control eddy currents in the Terfenol drive rod, and the effectiveness and the number of these slots were studied experimentally and calculated by finite element modeling. Based on the characteristic of vortex path, a new simple geometrical method to calculate the number of the radial slots of a Terfenol rod at the operating frequency is put forward in this paper. Moreover, the calculated results are in good agreement with those of using the finite element method (FEM) for the slotted Terfenol rod given by the literature. The method will save much cost to design Terfenol rod transducers.

关键词： Terfenol-D rod eddy current losses limit operating frequency

The study of adsorption gas sensor based carbon nanotube film

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science china(Technological sciences) 2005年第4期48卷 372-384页

作者： LI Xin1, LIU Junhua2 & ZHU changchun1 1. school of Electronic and Information Engineering, Xi’an Jiaotong university, Xi’an 710049, china 2. school of Electric Engineering, Xi’an Jiaotong university, Xi’an 710049, china 1. school of Electronic and Information Engineering Xi’an Jiaotong University 710049 Xi’an China 2. school of Electric Engineering Xi’an Jiaotong University 710049 Xi’an China

The study of gas sensitivity of multi-wall carbon nanotubes (MWNTs), which is deposited by low press chemical vapor deposition (LPCVD), is presented. The results show that the pure MWNTs are not sensitive to the gases measured, while the composite film consisting of the MWNTs and silicon dioxide is sensitive to the methane, the hydrogen and the acetylene. The MWNTs and silicon dioxide composite film have the capacitance characteristic because of the formation of Schottky junctions within the MWNTs. The chemistry adsorption of the gas measured on the surface of the MWNTs affects the space discharge area of the Schottky junction, so that the dielectric constant changes with the gas concentration. That is why the gas is sensed.

关键词： gas sensor, carbon nanotubes, low press chemical vapor deposition, scatter.

A new definition of restricted Lie superalgebras

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Chinese science Bulletin 2000年第4期45卷 316-321页

作者： WANG Ying & ZHANG Yongzheng1. Department of Mathematics, Harbin Institute Technology, Harbin 150001, china 2. Department of Mathematics, Northeast normal university, changchun 130024, china Department of Mathematics Harbin Institute Technology Harbin China Department of Mathematics Northeast Normal University Changchun China

A new definition of restricted Lie superalgebras has been given; some important results on the representation theory of restricted Lie superalgebra have been obtained.

关键词： restricted Lie superalgebra p-mapping p-semilinear mapping α-representation.