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Science china Earth sciences 2006年第5期49卷 554-560页

作者： FAN Ke1,2.3 & WANG Huijun2.1. Nansen-Zhu international Research center, Institute of Atmospheric {2., chinese academy of sciences, Beijing 10002., china 2. Department of Atmospheric Science, Yunnan University, Kunming 650091, china 3. Graduate University of the chinese academy of sciences, Beijing 100049, china Nansen-Zhu international Research center Institute of Atmospheric Physics Chinese Academy of Sciences Beijing China Department of Atmospheric Science Yunnan University Kunming China Graduate University of the chinese academy of sciences Beijing China

The interannual variability of Antarctic Oscillation (AAO) and its influence on East Asian climate during both boreal winter and spring are addressed. The results show that the positive AAO anomaly decreases the cold activity over East Asia during both boreal winter and spring. AAO-related barotropic meridional teleconnection from Antarctic to Arctic is found through analysis of mean me- ridional circulations. This meridional teleconnection is remarkable over Eurasia during boreal winter and over the Pacific Ocean during boreal spring. The results also show that zonal mean zonal wind at high latitudes in Southern Hemisphere has well positive correlation with that of Eurasia during boreal winter and has negative correlation with Pacific North American teleconnection (PNA) during boreal spring, which again display the meridional teleconnection. Thus, local meridional teleconnection is a possible linkage for interaction of circulations at mid-high latitudes between both hemispheres.

关键词： Antarctic Oscillation, Eurasian west wind, meridional teleconnection, mean meridional circulation.

2.2. chinese national clinical practice guideline on diagnosis and management of ulcerative colitis

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中华医学杂志(英文版) 2024年第14期137卷 1642-1646页

作者： Inflammatory Bowel Disease Group, chinese Society of Gastroenterology, chinese Medical Association Inflammatory Bowel Disease Quality Control {2. of china Inflammatory Bowel Disease Group Chinese Society of Gastroenterology Chinese Medical Association Inflammatory Bowel Disease Quality Control center of china

The role of chinese expert consensus in standardization and improvement of the clinical diagnosis and treatment of inflammatory bowel disease (IBD) is self-evident. As clinical and basic research in china becomes standardized under a better understanding of IBD, more data on chinese patients have become available to develop a consensus and guideline. This guideline, collaboratively developed by the IBD Group, chinese Society of Gastroenterology, incorporates the latest international consensus statements, domestic research findings, and practical considerations, as an update based on the 2.18 chinese consensus on IBD management. The IBD guideline consists of two parts: ulcerative colitis (UC) and Crohn's disease, and this manuscript presented the UC part. The evidence used in this guideline was collected and analyzed by the standard of guideline, and the contents were organized as problem statements, for clarity. The formulation of this guideline aimed to reflect the latest progress in IBD, providing comprehensive and valuable guidance for the clinical management of IBD.

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Statistical theory for hydrogen bonding fluid system of A_aD_d type (I): The geometrical phase transition

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Science china Chemistry 2006年第6期49卷 499-506页

作者： WANG Haijun1,2. HONG Xiaozhong3, GU Fang1 & BA Xinwu1 1. College of Chemistry and Environment Science, Hebei University, Baoding 071002. china 2. international {2. for Materials physics, chinese academy of sciences, shenyang 110016, china 3. College of physics Science and Technology, Hebei University, Baoding 071002. china College of Chemistry and Environment Science Hebei University Baoding China international center for Materials {2. Chinese Academy of Sciences Shenyang China College of physics Science and Technology Hebei University Baoding China

The influence of hydrogen bonds on the physical and chemical properties of hydrogen bonding fluid system of AaDd type is investigated from two viewpoints by the principle of statistical mechanics. In detail, we proposed two new ways that can be used to obtain the equilibrium size distribution of the hydrogen bonding clusters, and derived the analytical expression of a relationship between the hydrogen bonding free energy and hydrogen bonding degree. For the nonlinear hydrogen bonding systems, it is shown that the sol-gel phase transition can take place under proper conditions, which is further proven to be a kind of geometrical phase transition rather than a thermodynamic one. Moreover, several problems associated with the geometrical phase transition and liquid-solid phase transition in nonlinear hydrogen bonding systems are discussed.

关键词： hydrogen bonding fluid, equilibrium free energy, geometrical phase transition.

Dislocation Velocity Exponent and the Strain Rate

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Journal of Materials Science & Technology 2001年第3期17卷 363-366页

作者： Hongyan LIU and Xiaowei WANG international center for Material {2., Institute of Metal Research, chinese academy of sciences, shenyang 110016, china E-mail: liu@*** Intl. Cent. for Mat. Phys. Inst. of Metal Res. Chinese Acad. of Sci. Shenyang 110016 China

The process of dislocation multiplication has been described hv chaos theory, trying to reveal the connection between the microstructures on the mesoscopic scale and the mechanical properties of material on the macroscopic scale. The relationship between the dislocation velocity exponent and the maximum of strain rate is given. The results obtained from logistic equation with exponent and the dislocation multiplication dynamic equation are compared. A scale law in one-dimension-map model with exponent is shown when the exponents of equations are changed.

关键词： Dislocation Velocity Exponent and the Strain Rate

Ni-based Ni-Fe-B-Si-Ta bulk metallic glasses

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Science china(physics,Mechanics & Astronomy) 2010年第3期53卷 440-444页

作者： ZHU ChunLei1, WANG Qing1, ZHAO YaJun1, WANG YingMin1, QIANG JianBing1 & DONG Chuang1,2. Key Lab of Materials Modification (Ministry of Education), School of Materials Science and Engineering, Dalian University of Technology, Dalian 11602., china 2.international {2. for Materials physics, chinese academy of sciences, shenyang 110016, china Key Lab of Materials Modification (Ministry of Education) School of Materials Science and Engineering Dalian University of Technology Dalian China international center for Materials {2. Chinese Academy of Sciences Shenyang China

The glass-forming ability and properties of Ni-based Ni-Fe-B-Si-Ta bulk metallic glasses are explored in this work. The alloy compositions are determined by using a combination of the cluster line approach, the multi-alloying strategy and the substitutions of similar elements. Bulk metallic glasses with diameters of 3 mm take shape at compositions formulated under the clus- ter-plus-glue-atom model [M9B]B~[(Ni1-xFex)7.71(Si0.66Ta0.34)1.2.B]B0.94=(Ni1-xFex)70.5B17.7Si7.8Ta4, x=0.35–0.45, where the bracketed part is the cluster and the unbracketed part is the glue atoms. These alloys exhibit good magnetic properties. The maximum Is is found in the (Ni0.55Fe0.45)70.5B17.7Si7.8Ta4 alloy which reaches 0.51 T, with its Hc as low as 8.5 A/m. Interestingly, these alloys display dual glass transitions at (Ni0.65Fe0.35)70.5B17.7Si7.8Ta4, (Ni0.60Fe0.4)70.5B17.7Si7.8Ta4 and (Ni0.55Fe0.45)70.5B17.7- Si7.8Ta4 as unveiled by Temperature-Modulated Differential Scanning Calorimetry.

关键词： bulk metallic glasses cluster Ni-Fe-based alloys Modulated Differential Scanning Calorimetry

Effect of cyclic recovery heat treatment on surface recrystallization of a directionally solidified superalloy

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Progress in Natural Science:Materials international 2011年第6期21卷 491-495页

作者： Guang XIE~1,Jian ZHANG~(1,2.,Lang-hong LOU~1 1.Superalloys Division,Institute of Metal Research,chinese academy of {2.,shenyang 110016,china 2.shenyang National Laboratory for Materials Science,Institute of Metal Research, chinese academy of sciences,shenyang 110016,china Superalloys Division Institute of Metal Research Chinese Academy of Sciences Shenyang 110016 China shenyang National Laboratory for Materials Science Institute of Metal Research Chinese Academy of Sciences Shenyang 110016 China

Microstructural evolution and micro-hardness of a directionally solidified Ni-base superalloy subjected to shot-peening during cyclic recovery heat treatment was *** was found thatγ' dissolved and dislocation annihilation occurred during heating, while y' re-precipitated when temperature *** to the formation of a stable dislocation network at ylf interface,full recovery and therefore complete elimination of the surface recrystallization are difficult by the present cyclic recovery heat treatment.

关键词： recrystallization superalloy dislocation recovery heat treatment

Effects of Positron Diffusion and Its Application in Composite System

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Journal of Materials Science & Technology 2000年第3期16卷 311-314页

作者： Jian JIANG, Xinzhang ZHOU and ChiWei LUNG (international center for Materials {2., Institute of Metal Research, chinese academy of sciences, shenyang 110015, china) international center for Materials {2. Institute of Metal Research Chinese Academy of Sciences Shenyang 110015 China

The effects of positron diffusion on the measured S parameter have been investigated by a point-source diffusion model and a δ function method. Firstly, the theoretical analyses of the effects are presented for the samples of a homogeneous semi-infinite medium and a film of definite thickness. Then the results are used to analyze the S parameters in several composite systems and interface models.

关键词： Effects of Positron Diffusion and Its Application in Composite System

Nonlinear interactions between gravity waves and background winds

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Progress in Natural Science:Materials international 2007年第6期17卷 639-644页

作者： Liu Xiao1,2.and Xu Jiyao1(1. State Key Laboratory for Space Weather, center for Space Science and Applied Research, chinese academy of sciences, Beijing 100080,{2. 2. Graduate University of chinese academy of sciences, Beijing 100039,{2.) State Key Laboratory for Space Weather Chinese Academy of Sciences Beijing 100080 China center for Space Science and Applied Research Chinese Academy of Sciences Beijing 100080 China Graduate University Chinese Academy of Sciences Beijing 100039 China

Using the nonlinear propagating gravity waves (GW) model in the two-dimensional compressible atmosphere and the linear GW theory, the process of GW propagation in different background winds, e.g. the direction of the background wind is opposite to (dead wind) or the same as (tail wind) the direction of the horizontal phase velocity of GW, is studied. The results show that the dead wind prolongs the vertical wavelength and accelerates GW propagation. Therefore, GW propagates up to a higher height becomes instable in a short time and eventually induces an inverse jet flow. Then, the vertical wavelength is becoming short due to the nonlinear interactions between GW and the inverse jet flow. The vertical wavelength and group velocity decrease after GW propagates into the tail wind. The initial instable time is delayed. Although most of GW is trapped in the instable region, some of GW propagates above the instable region. Compared with GW propagation in the tail wind, the nonlinear interactions between GW and the dead wind are also strong. In contrast, the linear GW theory predicts that GW can propagate freely in the dead wind. The vertical wavelength simulated by the nonlinear numerical model is different from that predicted by the linear theory greatly after GW propagates into the dead wind.

关键词： gravity waves background winds vertical group velocity vertical wavelength nonlinear interactions.

Detecting forest landscape boundary between Mountain Birch and evergreen coniferous forest in the northern slope of Changbai Mountain

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Journal of Environmental sciences 2003年第2期15卷 182-186页

作者： CHANG Yu+1, BU Ren-cang+1, HU Yuan-man+1, XU Chong- gang+1, WANG Qing-li+2.(1. Institute of Applied Ecology, chinese academy of sciences, shenyang 110016,{2.. 2. shenyang Branch, CAS) Institute of Applied Ecology Chinese Academy of Sciences Shenyang 110016 China shenyang Branch CAS Shenyang China

Boundaries between different forest types in Changbai Mountain Eastern china are results from complex interactions between forest ecosystems, topography, and geomorphology. Detecting and quantifying the transitional zones are highly important since high environmental heterogeneity and biodiversity are often found within these zones. In this study, we used GIS and multivariate statistics techniques(PCA and MSWA) to analyze data from Landsat TM satellite imageries and quantitatively determined the positions and widths of the landscape boundary between mountain birch and evergreen coniferous forests in the northern slope of Changbai Mountain. The results showed that the widths of the landscape boundary ranges from 30—50m while using the MSWA or/and PC method. Such detected widths are consistent with field transect data that suggests a 50m transitional zone width. The results further suggest that TM data can be used in combination with GIS and statistical techniques in determining forest landscape boundaries; MSWA is more reliable than PCA, while PCA can also be used to determine the landscape boundary when transects are properly located.

关键词： Changbai Mountain forest landscape boundary PCA & MSWA

Unusual Behaviour of Dislocation Velocity Exponent in Dislocation Multiplication Model

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Journal of Materials Science & Technology 1998年第3期14卷 215-218页

作者： Xaowei WANG(international Centre for Materials physics, Institute of Metal Research,{2.,shenyang 110015, china) international Centre for Materials physics Institute of Metal Research Chinese Academy of Sciences Shenyang 110015 China

The chaotic behaviour of dislocation multiplication process was investigated. The change of Lyapunov exponent which is used to determine the stability of quasi-periodic and chaotic behavior as well as that of equilibrium points, and periodic solution was reported by using an iteration model of dislocation multiplication. An unusual behavior of Lyapunov exponent and Feigenbaum exponent which respond to the geometric convergence of orbit from bifurcation to chaos was shown by dislocation velocity exponent m and there is a distinction on the tendency of convergence for the dislocation multiplication model when it was compared with logistic map. It is reasonable for the difference to be analyzed from the materials viewpoint. (Edited author abstract) 9 Refs.

关键词： Unusual Behaviour of Dislocation Velocity Exponent in Dislocation Multiplication Model