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Fractal Structure of the Core Loss Spectrum of Co-based Amorphous Soft Magnetic Alloy with Constant Permeability

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International Journal of Minerals,Metallurgy and Materials 1999年第1期13卷 54-56页

作者： Yiping Chen (Applied Science School, university of Science and Technology beijing,{2., china) Applied Science School University of Science and Technology Beijing Beijing 100083 China

In order to check the traditional core loss formula, the core loss spectrum P(f) of Co-based amorphous soft magnetic alloy with constant permeability has been studied. It is found that within a high frequency range from 10 kHz to 2.0 kHz and at Bm = 0. 1 T,the P(f) has the fractal structure P (f) = Po, and with the increasing of induced anisotropy energy Ku, the fractal dimension Dfrises, thus the total power loss at high frequency increases and the frequency characteristic of P(f) becomes worse.

关键词： amorphous soft magnetic alloy constant permeability core loss fractal

Geological Controls on Seismic indicators of Volcanic Gas Reservoirs:A Case Study from the Changling Fault Depression of Songliao Basin,china

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地学前缘 2009年第S1期16卷 148-149页

作者： Lun Li,Xin Zhang School of Software,china university of {2.(beijing),beijing 100083,china.

The Songliao basin in northeast china is a Mesozoic rift basin characterized by Mesozoic and Cenozoic hydrocarbon *** Changling fault depression located in the south of the Songliao Basin,

关键词： volcanic gas reservoirs central eruption crevice eruption Changling depression

Producing Calcium-Bearing Mullite Thermal-Insulating Refractories by Kyanite

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International Journal of Minerals,Metallurgy and Materials 1999年第1期13卷 50-53页

作者： Wen Ni (Resources Engineering School, university of Science and Technology beijing,{2., china) Resources Engineering School University of Science and Technology Beijing Beijing 100083 China

To improve the physical properties, a series of experiments have been camed out to produce calcium-bearing mullite thermal-insulating refractories by using kyanite as major raw materials. The experiments were carried out by a foaming technique and using white cement as a combing agent. The results show that the calcium-bearing mullite refractory has much better physical properhes than traditional clay refractory and high-alumina refractory.

关键词： mullite thermal-insulating refractory kyanite

Calculation Models of Mass Action Concentrations for Metallic Melts Involving Monotectic

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Journal of university of Science and Technology beijing 2001年第4期8卷 248-253页

作者： Jian Zhang Metallurgy School, university of Science and Technology beijing,{2., china Metallurgy School University of Science and Technology Beijing Beijing 100083 China

Based on the phase diagrams, measured activities as well asDeltaG(m) and DeltaG(xs), calculating models of mass action concentrations for metallic melts involving monotectic have been formulated. The calculated results agree with practice on the whole, showing that the models deduced generally can reflect the structural characteristics of these melts. The metastable compounds formed in the melts are of the types A(2.B(3), AB(2., A(2.B(3) or AB and A(2.B(3)+AB etc..

关键词： metallic melts monotectic activity mass action concentration

Protective Effects of Vitamin E against Oxidative Damage Induced by Aβ(1-40)Cu(Ⅱ)Complexes

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Acta Biochimica et Biophysica Sinica 2007年第2期39卷 123-130页

作者： Xueling DAI~1 Yaxuan SUN~2.and Zhaofeng JIANG~2.~1College of Life Science,Capital Normal university,Bejing 100037,china ~2.ollege of Applied Sciences Humanities of {2. Union university,{2. 100083,china College of Life Science Capital Normal UniversityBeijing 100037 China College of Applied Sciences and Humanities of beijing Union universitybeijing 100083 China

β-amyloid peptide （Aβ） is considered to be responsible for the formation of senile plaques,which is the hallmark of Alzheimer's disease （AD）.Oxidative stress,manifested by protein oxidation andlipid peroxidation,among other alterations,is a characteristic of AD brain.A growing body of evidence hasbeen presented in support of Aβ1-40forming an oligomeric complex that binds copper at a CuZn superoxidedismutase-like binding site. Aβ1-40Cu（Ⅱ） complexes generate neurotoxic hydrogen peroxide （H2.2. from O2.ia Cue+ reduction,though the precise reaction mechanism is *** toxicity of Aβ1-40or the Aβ1-40Cu（Ⅱ）complexes to cultured primary cortical neurons was partially attenuated when （+）-α-tocopherol （vitamin E）as free radical antioxidant was added at a concentration of 100 μ*** data derived from lactate dehydro-genase （LDH） release and the formation of H2.2.onfirmed the results from the MTT *** findingsindicate that copper binding to Aβ1-40can give rise to greater production of H2.2. which leads to a break-down in the integrity of the plasma membrane and subsequent neuronal *** treated with vitaminE exhibited much slighter damage,suggesting that vitamin E plays a key role in protecting neuronal cellsfrom dysfunction or death.

关键词： Aβ1-40Cu(II)complex vitamin E neuronal oxidative damage H2.2.generation lactate dehydrogenase(LDH)release

CABOSFV algorithm for high dimensional sparse data clustering

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Journal of university of Science and Technology beijing 2004年第3期11卷 283-288页

作者： Sen Wu Xuedong Gao Management School, university of Science and Technology beijing,{2., china Mgmt. Sch. Univ. of Sci. and Technol. Beijing Beijing 100083 China

An algorithm, Clustering Algorithm Based On Sparse Feature Vector (CABOSFV),was proposed for the high dimensional clustering of binary sparse data. This algorithm compressesthe data effectively by using a tool 'Sparse Feature Vector', thus reduces the data scaleenormously, and can get the clustering result with only one data scan. Both theoretical analysis andempirical tests showed that CABOSFV is of low computational complexity. The algorithm findsclusters in high dimensional large datasets efficiently and handles noise effectively.

关键词： clustering data mining sparse high dimensionality

Sulfide-melt inclusions in mantle xenoliths of Hannuoba,china

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Chinese Science Bulletin 1999年第2期44卷 166-170页

作者： XU Jiuhua , CHU Xuelei , ZHOU Yiming , DU Yuanfuuniversity of Science and Technology beijing,{2., china china university of geosciences( beijing) ,{2., china The Research Center of Mineral Resources Exploration , beijing 100101, china Institute of Geology, Chinese Academy of Sciences, beijing 10002., china university of Science and Technology beijing Beijing China china university of {2. (beijing) Beijing China The Research Center of Mineral Resources Exploration Beijing China Institute of Geology Chinese Academy of Sciences Beijing China

Sulfide fluid incluision study on mantle xenoliths of Hannouba has been carried out by EPMA analysis. It is indicated that the Ni/Fe ratios of metal sulfides in sulfide-melt inclusions from Hannuoba seem to be related to host rocks. These data of lherzolite （pentlandite） are obviously higher than those of olivine pyroxenite （mainly pentlandite, partly pyrrhotine）. The LRM analysis shows that sulfur （H2./sub>S+SO2./sub>） occupies larger proportion in gas composition of CO2./sub> fluid inclusions, generally more than mol 2. %. This may be related to sulfide inclusions which are frequently found.

关键词： mantle xenolith sulfide-melt inclusion EPMA.

Microstructural Features During Strain Induced Ferrite Transformation in 08 and 2.Mn Steels

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Journal of university of Science and Technology beijing 2001年第2期8卷 105-110页

作者： Ping Yang, Feng-e Cui, Fuming Wang (Materials Science and Engineering School, university of Science and Technology beijing,{2., china) (Metallurgy School, university of Science and Technology beijing,{2., china) Materials Sci. and Eng. School University of Science and Technology Beijing 100083 China

The microstructure evolution during strain induced ferrite transformation was followed in thermal-simulation tests of clean 08 and 2.Mn steels. The influences of carbon equivalence and initial austenite grain size on ferrite grain refinement and the volume fraction of ferrite during straining were inspected. The results revealed that the accelerating effect of ferrite transformation by strain was increased as the carbon equivalence decreased. However, finer ferrite grains were obtained at higher carbon content. At strain of similar to1.5 ferrite grains less than 3 mum and 2.mum can be obtained in 08 and 2.Mn steels respectively. Whereas the ferrite grain refinement in 08 steel was due to both effects of strain induced transformation and ferrite dynamic recrystallization, that in 2.Mn was mainly due to strain induced transformation. Heavy strain can produce fine ferrite grains in coarse austenite grained 08 steel, but it would lead to band microstructure in coarse austenite grained 2.Mn.

关键词： clean carbon steel strain induced transformation grain refinement ferrite dynamic recrystallization

A New SHRIMP Age of the Xiamaling Formation in the North china Plate and Its Geological Significance

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Acta Geologica Sinica(English Edition) 2007年第6期81卷 1103-1109页

作者： GAO Linzhi~(1,*)ZHANG Chuanheng~2.SHI Xiaoying~2.ZHOU Hongrui~2.WANG Ziqiang~2.SONG Biao~(1,3) 1 Institute of Geology,Chinese Academy of Geological Sciences,beijing 100037,china 2.2. university of geosciences(beijing),beijing 100083,china 3 beijing SHRIMP Central,100037 beijing,china Chinese Acas Geol Sci Inst Geol Beijing 100037 Peoples R China beijing SHRIMP Cent Beijing 100037 Peoples R China china Univ Geosci Beijing 100083 Peoples R China

Setting up the hypostratotype of late Precambrian is the main aim of the research on the Meso-and Neoproterozoic in North *** chronostratigraphic position is the key in this study. However,many key horizons have not been calibrated with the high-quality isotopic *** the reported new U-Pb age with the Sensitive High-Resolution Ion Microprobe（SHRIMPⅡ）,a zircon U- Pb age was obtained of the ash bed in the Xiamaling Formation in North china Plate,yielding a weighted mean;Pb/;U age of 1368±12.*** is the first SHRIMP U-Pb age from the Xiamaling Formation in the North china Plate,and represents the depositing time of the middle part of the Xiamaling *** zircon age plays an important role to understanding geological evolution of the North china Plate during Meso-and Neoproterozoic.

关键词： SHRIMP U-Pb Dating Mesoproterozoic Xiamaling Formation North china Plate