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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, beijing 100083, china 2. Institute of Geology, Chinese Academy of Sciences, beijing 100029, china 1. china University of Geosciences 100083 Beijing China 2. Institute of Geology Chinese Academy of Sciences 100029 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=4.3191(2) nm, V=8.5736 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.

Indian Ocean-MORB-type isotopic signature of Yushigou ophiolite in North Qilian Mountains and its implications

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Science china Earth Sciences 2006年第6期49卷 561-572页

作者： HOU Qingye1,2, ZHAO Zhidan1,2, ZHANG Hongfei3, ZHANG Benren3 & CHEN Yuelong2 1. State Key laboratory of Geological Processes and Mineral Resources, china University of Geosciences, beijing 100083, china 2. School of Earth Science and Mineral Resources, china University of Geosciences, beijing 100083, china 3. Faculty of Earth Sciences, china University of Geosciences, Wuhan 430074, china 1. State Key laboratory of Geological Processes and Mineral Resources China University of Geosciences Beijing 100083 China 2. School of Earth Science and Mineral Resources China University of Geosciences Beijing 100083 China 3. Faculty of Earth Sciences China University of Geosciences Wuhan 430074 China

In order to explore the disputed issue concerning the tectonic affinity ofthe ancient ocean mantle of North Qilian Mountains (NQM), geochemical and Sr, Nd, Pb isotopiccompositions of pillow basalts of the Yushigou Ophiolite (YSGO) suite from NQM have been analyzedsystematically. The pillow basalts exhibit tholeiitic characteristics, with flatchondrite-normalized REE patterns ((La/Yb)_N = 0.98—1.27). They display no Nb, Ta, Zr, Hf negativeanomalies, and show MORB features in 2Nb-Zr/4-Y and Ti/100-Zr-YX3 tectonic discrimination *** results indicate that the Yushigou ophiolite is most likely to be formed in a mid-ocean ridgeor mature back-arc basin. Their isotopic data show a relatively broad and enriched ^(87)Sr/^(86)Sr(0.70509 — 0.70700), restricted ^(143)Nd/^(144)Nd (0.512955-0.512978). Pb isotopes are in the rangeof ^(206)Pb/^(204)Pb (18.054-20.562), ^(207)Pb/^(204)Pb (15.537-15.743) and ^(208)Pb/^(204)Pb(38.068-38.530). These isotopic data imply that the basalts originated from the depleted mantle(DMM), with the involvement of enriched mantle components (mainly EMII). Geochemical comparisonsbetween the basalts in YSGO and the MORB-type basalts of ophiolite suites occurring in the knownancient Tethyan tectonic domain indicate that the ancient oceanic mantle represented by YSGO suiteforming in early Paleozoic in the North Qilian Moutains is very similar to the Tethyan mantle inboth trace elements and isotopic compositions. The North Qilian Mountains should be a part of theTethyan tectonic domain in early Paleozoic. This further implies that the Tethyan tectonic domaincan be deduced to early Paleozoic in the study area, which will be helpful to discussing thetectonic affinity and evolution of the North Qilian Mountains.

关键词： geochemistry, Indian Ocean-MORB-type isotopic signatures, Tethyan tectonic domain, Yushigou ophiolite, North Qilian Mountains.

Pattern phenomena in an rf discharge dusty plasma system

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Science china(Physics,Mechanics & Astronomy) 2006年第5期49卷 588-596页

作者： HUANG Feng1,2, YE Maofu2 & WANG Long2 1. College of Science, china Agricultural University, beijing 100083, china 2. Institute of Physics, Chinese Academy of Sciences, beijing 100080, china 1. College of Science China Agricultural University Beijing 100083 China 2. Institute of Physics Chinese Academy of Sciences Beijing 100080 China

Various dust patterns are observed in an rf discharge dusty plasma system. According to the dust growth process from small to large in size, the formation of different dust patterns can be divided into two stages: the small-particle stage (or dust cloud stage), and the large-particle stage (or dust crystal stage). The evolution relations between different dust patterns with gas pressure changing are investigated. Dust voids, dust acoustic waves and strong turbulence modes are presented at the small-particle stage. The self-organized dust lattices and dust clusters are investigated at the large-particle stage. The static structure of a dust lattice is characterized by means of the pair correlation function. Dust clusters formed by particles with different numbers and the regular evolution of the clusters with gas pressure are also investigated. The packing sequences of dust clusters are verified through two-dimensional confined molecular dynamics simulations.

关键词： dusty plasma dust patterns

Calculating Models of Mass Action Concentrations for Fe-P and Cr-P Melts and Optimization of Their Thermodynamic Parameters

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International Journal of Minerals,Metallurgy and Materials 1999年第3期13卷 174-177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, reliable reference experimental data and the coexistence theory of metallic melts structure involving compound formation, calculating models of mass action concentrations for Fe-P and Cr-P melts have been formulated. At the same time, some of their thermodynamic parameters have been optimized. The calculated results not only agree well with the measuredvalues, but also obey the mass action law rigorously, this in turn shows that these models can reflect the structural characteristics of corresponding melts.

关键词： activity phase diagram coexistence theory mass action concentration

Cardiovascular Risk Factors in china

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Journal of Geriatric Cardiology 2024年第2期21卷 153-199页

作者： Sheng-Shou HU the Writing Committee of the Report on Cardiovascular Health and Diseases in china Fuwai Hospital National Center for Cardiovascular DiseasesChinese Academy of Medical Sciences and Peking Union Medical CollegeBeijingChina 不详

The Annual Report on Cardiovascular Health and Diseases in china(2022) intricate landscape of cardiovascular health in china. This section dissects cardiovascular risk factors in china which including hypertension, dyslipidemia, diabetes mellitus, chronic kidney disease, metabolic syndrome and air pollution. Hypertension prevalence has steadily increased in china,with efforts to control it facing challenges in achieving optimal rates, especially in rural areas. Interventions like salt substitutes and intensive blood pressure control show promise but need improvement. Abnormal lipid levels, indicative of dyslipidemia,have risen significantly, posing a risk for cardiovascular diseases. Despite efforts, many patients struggle to achieve target lipid levels, necessitating improved treatment strategies. Both type 1 and type 2 diabetes mellitus affect millions of adults in china,with long-term complications adding to the disease burden. Early intervention and effective management are crucial to mitigate its impact. Prevalent among older adults, chronic kidney disease is associated with diabetes mellitus, hypertension, and cardiovascular diseases, necessitating comprehensive management approaches. The prevalence of metabolic syndrome, characterized by a cluster of risk factors, has increased in both adults and adolescents, calling for lifestyle modifications and public health interventions. Ambient and household air pollution remain significant environmental risk factors, despite some improvements in air quality. Continued efforts to reduce emissions are essential for mitigating associated health risks. Addressing these risk factors requires a multifaceted approach, including public health initiatives, policy interventions, and individual-level strategies to promote healthy lifestyles and reduce environmental exposures. Surveillance and research efforts are crucial for monitoring trends and developing effective strategies to lessen the burden of cardiovascular diseases in

关键词： landscape adding spite

Al_2O_3/Au Composite Coating on Stainless Steel Prepared by Electro-deposition

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稀有金属材料与工程 2012年第S1期41卷 108-112页

作者： Jin Zhang,Sha Lan,Yedong He beijing Key laboratory for Corrosion,Erosion and Surface Technology,University of Science and Technology beijing,beijing 100083.china Univ Sci & Technol beijing Beijing Key Lab Corros Eros & Surface Technol Beijing 100083 Peoples R China

Tritium permeation barriers on stainless steels are required in fusion technology in order to reduce the tritium permeation rate through the structural material into the cooling water *** of tritium permeation barrier Al2O3 is an important way to solve the problem of leakage of tritium *** is worth to note that the noble Au is an excellent barrier of hydrogen ***2O3/Au composite coating was designed for potential tritium permeation barrier on stainless *** alternation coatings have been prepared by electrochemical deposition *** processing parameters and subsequent sinter temperature for composite coatings were *** oxidation resistance of the coating has been tested.A hydrogen diffusion test simulating tritium permeation has been conducted to compare the sample with and without *** was examined by scanning electron microcopy(SEM).The results showed Al2O3/Au multi-alternation coatings can be prepared on the surface of stainless steel at the case of controlling processing *** coatings have the characteristic of high temperature oxidation resistance and good hydrogen permeability *** tritium permeation should be study further.

关键词： electrochemical deposition Al2O3/Au coating tritium permeation barriers

A Back Look on the Binary Phase Diagrams of Metals from the Mass Action Law and the Coexistence Theory of Metallic Melts

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Journal of University of Science and Technology beijing 2001年第1期8卷 15-19页

作者： Jian Zhang Metallurgy School, University of Science and Technology beijing, beijing 100083, china Univ Sci & Technol beijing Met Sch Beijing 100083 Peoples R China

According to the mass action law and the coexistence theory of metallic melts, the mass action concentrations of Cu-Mg, Bi-Tl and Ni-Al melts involving compound formation have been calculated. The calculated results show that, except the ultimate case of pure element, when two elements are present in the melts, all structural units (atoms and molecules) without exception will be present in the melts, i.e., their concentrations may change from great to small, but they will not vanish into nothing, and only under such conditions, the calculated results both agree with practice and obey the law of mass action. In view of that over considerable wide composition range, the activities of both elements of the three solid binary alloys mentioned above have been measured, this seems in contradiction with the present relevant phase diagrams, in which the structural units are determined by composition range, so the latter needs further investigation and consideration.

关键词： activity phase diagram the mass action law the coexistence theory

Heart failure in china:epidemiology and current management

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Journal of Geriatric Cardiology 2024年第6期21卷 631-641页

The Annual Report on Cardiovascular Health and Diseases in china(2022)intricate landscape of cardiovascularhealth in *** connection with the previous section,this sixth section of the report offers a comprehensive analysis of heart failure(HF)in *** is one of the most important cardiovascular disease in the 21st *** mortality is equivalent to that of *** is an important public health problem that seriously affects the health of Chinese *** recent years,with the deepeningof understanding,the change of treatment principles,the innovation of treatment methods and the update of treatment guidelines,the in-hospital mortality of HF patients has declined,and the long-term prognosis is also ***,there are stilldifferences in the management level of HF among different hospitals in *** to improve the standardized diagnosis andtreatment level of HF in china remains an important challenge.

关键词： epidemiology diagnosis treatment

Influence of sample surface condition on nano indentation experiment

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Rare Metals 2002年第2期21卷 131-132页

作者： WANG Yanli, LIN Zhi, LIN Junpin, PENG Jihua, and CHEN GuoliangState Key laboratory for Advanced Metals and Materials, University of Science and Technology beijing, beijing 100083, china University of Science and Technology beijing State Key Laboratory for Advanced Metals and Materials 北京 100083

The microhardness and elastic modules of the materials weremeasured using the Nano Indenter II, which is a new measuring systemfor the mechanical properties of materials on nano-scale. It candetermine themicrohardness, elastic modules and other mechanicalproperties of materials through measuring applied load and depthunder indenter tip. The results indicated that surface condition ofsample such as the surface roughness affects the experimental preci-sion.

关键词： microhardness elastic modules Nano Indenter