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Mineralogy and crystal structure determination of Mg-fillowite

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Science china Earth Sciences 2005年第5期48卷 635-646页

作者： MA Zhesheng 1 , SHI Nicheng 1 & YE Danian 2 1. china university of geosciences,{3. 2. Institute of Geology, Chinese Academy of Sciences, beijing 100029, china china university of geosciences Beijing China Institute of Geology Chinese Academy of Sciences Beijing China

Accurate crystal structure determination of complex phosphate Mg-fillowite ? Na2Ca(Mn4Mg2Fe)7[PO4]6 has been finished. Mg-fillowite occurs in muscovite-pegmatite in the Altay area, Xinjiang, china. It is of the trigonal lattice, with space group R-3. unit cell a=1.5143.3. nm, c=4.3.91(2) nm, V=8.573. nm3. Z = 18. The R-factor of the determination accuracy is R (I > 2σ ( I )) = 0.0776. The cationic polyhedra consist of two kinds of structural units: compound col- umn and screw column. In three-dimensional space, they are linked with each other through corner sharing or edge sharing to build the entire structure. There are 45 atoms in an asymmetric unit and 720 atoms in a unit cell. In terms of types and connection manners of the coordination polyhedra, the degree of complicity is rarely seen in all mineral crystal structures. Study of such a structure is significant for the classification of phosphate and the building rule of coordination polyhedra in a complex crystal structure.

关键词： Mg-fillowite, complex phosphate, crystal structure, coordination polyhedron.

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 geosciences({3.),{3. 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

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, beijing 100083. 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

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, beijing 100083. 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

A New Safety Electric Initiating System

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International Journal of Minerals,Metallurgy and Materials 1999年第4期13卷 306-308页

作者： Daze Lin(Resource Engineering School, university of Science and Technology beijing, beijing 100083. china) Univ of Science and Technology Beijing Beijing China

Based on the analysis of weakness on the safety of traditional electric detonators, a BJ-l safety electric detonator initiatingsystem and its corresponding safe examination technique were successfully developed. By leading false foot wires and taking advantageof the transmitting frequency band of Mo-Zn ferrite, detonators in this new system can completely impede the direct induction of outsidecrosstalk that may cause casual firing in the ordinary as well as eleclromagnetic ones. Possible causality by lightning was discussed. Results are presented, of its safety tests on resistance to direct and alternating current, electrostatic, and crosstalk induced by damp leakagein saturated salty water.

关键词： electric detonator blasting engineering, electric initiating system, safety

Microstructural Features During Strain Induced Ferrite Transformation in 08 and 20Mn 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, beijing 100083. china) (Metallurgy School, university of Science and Technology beijing, beijing 100083. 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 20Mn 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 20Mn 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 20Mn 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 20Mn.

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

Real-World Treatment Adherence to Smoking Cessation Medications and Association with Treatment Outcome—27 Centers,china,2017–2022

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china CDC weekly 2024年第22期6卷 522-529,I0001-I0003页

作者： Anqi Cheng Zhao Liu Xinmei Zhou Zheng Su Dan Xiao Chen Wang the china National Tobacco Cessation Cohort Study(CNTCCS)Study Group Department of Tobacco Control and Prevention of Respiratory Disease Center of Respiratory MedicineChina-Japan Friendship Hospital/WHO Collaborating Center for Tobacco Cessation and Respiratory Diseases Prevention/National Center for Respiratory Medicine/National Clinical Research Center for Respiratory Diseases/Institute of Respiratory MedicineChinese Academy of Medical SciencesBeijingChina Department of Pulmonary and Critical Care Medicine Center of Respiratory MedicineChina-Japan Friendship Hospital/WHO Collaborating Center for Tobacco Cessation and Respiratory Diseases Prevention/China National Center for Respiratory Medicine/China National Clinical Research Center for Respiratory DiseasesBeijingChina Chinese Academy of Medical Sciences and Peking Union Medical College BeijingChina 不详

What is already known about this topic?Medication non-adherence significantly impedes smoking cessation *** effective smoking cessation medications are accessible in china,realworld adherence and its correlation with treatment outcomes remain largely *** is added by this report?From December 2017 to January 2022,1,120 participants were recruited from 27 centers in all seven geographical regions of *** revealed that only 3..2%of smokers adhered to the prescribed 12-week smoking cessation treatment and those with a higher education level were more likely to be *** addition,smokers with good adherence were more likely to successfully quit *** are the implications for public health practice?The data obtained could enhance our understanding of smoking cessation practices in *** adherence is a crucial strategy to enhance the effectiveness of smoking cessation treatments and management provided to smokers.

关键词： china smoke likely

A New Method for Fractal Dimension Determination by STM at Nanometer Scale

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International Journal of Minerals,Metallurgy and Materials 1999年第1期13卷 64-68页

作者： Qikai Li Yue Zhang Wuyang Chu Chen Wang Chunli Bai (Applied Science School. university of Science and Technology beijing, beijing 100083. china)(Chemical Institute, Chinese Academy of Science, beijing 100080. china) Applied Science School University of Science and Technology Beijing Beijing 100083 China Chemical Institute Chinese Academy of Science Beijing 100080 China

A new method for determining the fractal dimension by STM at nanomeler scale has been ***- Mandelbrot fractal curves were used to verify the accuracy and reliability. The Computer simulation showed that fractal dimen- sion obtained with this method generally outran the traditional yard method. The new method has been applied to the fractal dimension determination of the fractures of Ti3.l and Ti-24Al-11Nb alloys. The results show that the fractal dimension of Ti-24Al-11Nb alloy is higher than that of Ti3.l, and it varies with the crark extending orientation.

关键词： fractal dimension STM nanometer scale Ti-Al alloy

Spatio-temporal carbon isotope variation during the Ediacaran period in South china and its impact on bio-evolution

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Science china Earth Sciences 2009年第10期52卷 1520-1528页

作者： WANG XinQiang1 & SHI XiaoYing1,2 1 School of Earth Science and Mineral Resources, china university of geosciences,{3. 2 State Key Laboratory of Geological Processes and Mineral Resources,{3. School of Earth Science and Mineral Resources China University of Geosciences Beijing China State Key Laboratory of Geological Processes and Mineral Resources Beijing China

The Ediacaran period is characterized by the extremely negative carbon isotope anomalies and great biotic evolution in Earth history. At least four negative carbon isotope anomalies have been reported from this interval in South china so far. It is traditionally argued that the isotope variations can be used as a useful tool for global correlation of Ediacaran succession; however, more and more researches argued against this idea. We reviewed the previously published carbon isotope data in South china, and distributed the mean values of a certain time to the paleogeographic maps. The results show that the carbon isotope values (δ13.) vary greatly in different environments, but a clear tendency of becoming lighter from shallow platform to deep basin, with a maximum variation up to 1‰ Moreover, the important changes in Ediacaran biota, marked by the introducing of new taxa or ecologic groups, seemed to always postdate the negative anomalies but coincide with the positive shift. If the negative excursions represented the oxidation of a large dissolved organic carbon (DOC) reservoir in the ocean, the diverse Ediacaran organisms and the carbon isotope anomalies may suggest totally different environments: oxic and anoxic/euxinic. We also suggest that the elimination of euxinic state through precipitation of pyrites is one of the important environment factors in prompting the Ediacaran bio-evolution.

关键词： Ediacaran South china carbon isotope spatio-temporal variations bio-evolution