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Application of MgO-CaO Refractories in Secondary Refining Furnaces

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China's Refractories 2012年第1期21卷 11-16页

作者： GAO Xinkui1,YIN Guoxiang1,2.1 Yingkou Qinghua Refractories Co. ,Ltd. ,Dashiqiao 115100,China 2.School of Materials science and Engineering,university of science and {3. Beijing,Beijing 100083.China Yingkou Qinghua Refractories Co. Ltd Dashiqiao 115100 China School of Materials science and Engineering University of Science and Technology Beijing Beijing 100083 China

The development status, production technology and characteristics of MgO-CaO refractories are introduced, covering MgO-CtlO clilnkers, fired MgO-CaO bricks and unburned MgO-CaO-C bricks. The applications o! MgO-CaO re... 详细信息

关键词： magnesia calcia clinkers magnesia calciabricks: magnesia calcia carbon bricks secondaU refining

Preparation and characterization of Eu^(3.)-doped CaCO_3.phosphor by microwave synthesis

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Rare Metals 2009年第5期28卷 439-444页

作者： KANG Ming LIU Jun YIN Guangfu SUN Rong School of Materials science and Engineering Southwest University of Science and Technology Mianyang 621010 China College of Materials Sctence and Engmeering Stchuan University Chengdu 610065 China Shenzhen Ocean＇s King Lighting science and technology Co. LTD. Shenzhen 518000 China

A Eu^3.-doped CaCO3.phosphor with red emission was prepared by microwave synthesis. The scanning electron microscopy （SEM） image and laser particle size analysis show that the CaCO3.Eu^3. particles are needle-like in the length range of 5.0-10.0 μm. The results of X-ray diffraction （XRD） analysis, Fourier transform infrared spectroscopy （FT-IR）, and Raman spectroscopy indicate that pure aragonite CaCO3.Eu^3. is prepared using microwave irradiation and the Eu^3. ion as a luminescence center inhabits the site of Ca^2.. The photoluminescence excitation （PLE） spectrum shows that the strong broad band at around 2.0 nm and weak sharp lines in 3.0-550 nm are assigned to the charge transfer band of Eu^3.-O^2. and intra-configurational 4f-4f transitions of Eu^3., respectively. The photoluminescence （PL） spectrum implies that the red luminescence can be attributed to the transitions from the ^5D0 excited level to the ^7FJ （J = 0, 1, 2. 3. 4） levels of Eu^3. ions with the mainly electric dipole transition ^5D0 → ^7F2.（614 and 62. nm）, and the Eu^3. ions prefer to occupy the low symmetric site in the crystal lattice.

关键词： phosphors calcium carbonate Eu^3.-doped microwave synthesis photoluminescence

A CLASS OF LDPC CODE'S CONSTRUCTION BASED ON AN ITERATIVE RANDOM METHOD

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Journal of Electronics(China) 2006年第1期23卷 124-127页

作者： Huang Zhonghu Shen Lianfeng National Mobile Communication Research Lab Southeast University Nanjing 210096 China institute of Communication Eng. University of Science and Technology of PLA Nanjing 210007 China

This letter gives a random construction for Low Density Parity Check (LDPC) codes, which uses an iterative algorithm to avoid short cycles in the Tanner graph. The construction method has great flexible choice in LDPC code's parameters including codelength, code rate, the least girth of the graph, the weight of column and row in the parity check matrix. The method can be applied to the irregular LDPC codes and strict regular LDPC codes. Systemic codes have many applications in digital communication, so this letter proposes a construction of the generator matrix of systemic LDPC codes from the parity check matrix. Simulations show that the method performs well with iterative decoding.

关键词： Low Density Parity Check (LDPC) codes Sum Product Algorithm(SPA) Random construction Algebraic construction Parity check matrix Generator matrix

GdFeCo/DyFeCo交换耦合两层薄膜磁化方向转变的研究

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物理学报 2004年第2期53卷 614-619页

作者：张约品王现英林更琪李震李佐宜沈德芳干福熹中国科学院上海光学精密机械研究所华中科技大学电子科学与技术系武汉430074

用磁控溅射法制备了GdFeCo DyFeCo交换耦合两层薄膜 ,对交换耦合两层薄膜变温磁化方向进行了研究 .结果表明读出层GdFeCo随温度上升从平面磁化转变成垂直磁化 ,转变过程中主要受饱和磁矩 (Ms)的影响 .在GdFeCo的补偿温度附近 ,读出层的... 详细信息

用磁控溅射法制备了GdFeCo DyFeCo交换耦合两层薄膜 ,对交换耦合两层薄膜变温磁化方向进行了研究 .结果表明读出层GdFeCo随温度上升从平面磁化转变成垂直磁化 ,转变过程中主要受饱和磁矩 (Ms)的影响 .在GdFeCo的补偿温度附近 ,读出层的磁化强度近于零 ,退磁场能减小 ,并在交换耦合的作用下 ,使读出层的磁化方向发生转变。

关键词：磁光记录交换耦合两层薄膜磁化方向转变磁控溅射法饱和磁矩补偿温度磁化强度中心孔磁超分辨效应

MICROSTRUCTURE AND MECHANICAL PROPERTIES OF TiAl+Nd ALLOYS

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中国有色金属学会会刊：英文版 1996年第3期6卷 140-142页

作者： Lei Changming He Yuehui Chen Shiqi Qu Xuanhui Huang Baiyun(Research institute of powder MetallurgyCentral South university of {2., Changsha 410083. CENT S UNIV TECHNOL RES INST POWDER METCHANGSHA 410083PEOPLES R CHINA

ＭＩＣＲＯＳＴＲＵＣＴＵＲＥＡＮＤＭＥＣＨＡＮＩＣＡＬＰＲＯＰＥＲＴＩＥＳＯＦＴｉＡｌ＋ＮｄＡＬＬＯＹＳ￥ＬｅｉＣｈａｎｇｍｉｎｇ；ＨｅＹｕｅｈｕｉ；ＣｈｅｎＳｈｉｑｉ；ＱｕＸｕａｎｈｕｉ；ＨｕａｎｇＢａｉｙｕｎ（Ｒ... 详细信息

ＭＩＣＲＯＳＴＲＵＣＴＵＲＥＡＮＤＭＥＣＨＡＮＩＣＡＬＰＲＯＰＥＲＴＩＥＳＯＦＴｉＡｌ＋ＮｄＡＬＬＯＹＳ￥ＬｅｉＣｈａｎｇｍｉｎｇ；ＨｅＹｕｅｈｕｉ；ＣｈｅｎＳｈｉｑｉ；ＱｕＸｕａｎｈｕｉ；ＨｕａｎｇＢａｉｙｕｎ（Ｒｅｓｅａｒｃｈｉｎｓｔｉｔｕｔｅｏ...

关键词： TiAl based alloy Nd microstructure mechanical properties

Benthic foraminifera and bottom water evolution in themiddle-southern Okinawa Trough during the last 18 ka

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science China Earth sciences 2005年第6期48卷 805-814页

作者： LI Tiegang1, XIANG Rong1,2. SUN Rongtao1 & CAO Qiyuan1 1. institute of Oceanology, Chinese Academy of sciences, Qingdao 2.6071, China 2. College of Geosciences, Ocean {3. of China, Qingdao 2.6003. China Correspondence should be addressed to Li Tiegang 1. institute of Oceanology Chinese Academy of Sciences 266071 Qingdao China 2. College of Geosciences Ocean University of China 266003 Qingdao China

A piston sediment core E017 from the middle-southern Okinawa Trough was investigated. A preliminary study of the deep-water evolution since 18 cal. ka BP was performed basedon the quantitative census data of benthic foraminiferal fauna, together with planktonic foraminiferal oxygen and carbon isotope, AMS14C dating, and the previous results achieved in thesouthern Okinawa Trough. The result shows that the benthic fauna was dominated by Buliminaaculeata (d′Orbigny), Uvigerina peregrina (Cushman), Hispid Uvigerina and Uvigerina dirupta(Todd) during the glaciation-deglaciation before 9.2.cal. ka BP, while Epistominella exigua(Brady), Pullenia bulloides (d′Orbigny), Cibicidoides hyalina (Hofker), Sphaeroidina bulloides(d’Orbigny) and Globocassidulina subglobosa (Brady) predominated the fauna in the post-glaciaperiod after 9.2.cal. ka BP. The benthic foraminifera accumulation rate (BFAR), paleoproductivityestimates and benthic foraminiferal assemblage conformably indicate that surface water paleoproductivity and organic matter flux during the glaciation-deglaciation were higher than those othe post-glacial period in the middle-southern Okinawa Trough, and gradually enhanced from thesouthern to the central Okinawa Trough during the glaciation-deglaciation, which could becaused by the discrepancy of the terrigenous nutrients supply. High abundances of E. exigua, anindicator of pulsed organic matter input, after 9.2.cal. ka BP may indicate that the intensity oseasonally riverine pulsed flux during the post-glacial period was stronger than that of the glaciation-deglaciation period, and the seasonal influx in the central trough might be stronger than inthe south. The temporal distributions of the typical species indicating bottom water oxygen content and ventilation condition show that the ventilation of the bottom water during the post-glaciaperiod is more active than the glaciation-deglaciation, which reflects that the evolution of the intermediate and deep waters of the n

关键词： benthic foraminifera, the Okinawa Trough, deep-water evolution.

Conductance and dielectric properties of pure C_(60) single crystal

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Chinese science Bulletin 1997年第1期42卷 40-43页

作者： YANG Guoquan, WANG Gang, WEN Weijia, ZHOU Weiya, LU Kunquan and XIE Sisheng1. Central university for Nationalities, Beijing 100081, China 2. institute of Physics, Chinese Academy of {2.s, Beijing 100080, China Central university for Nationalities Beijing China institute of Physics Chinese Academy of Sciences Beijing China

THE C60 is the third stable allotrope of carbon. Much attention has been focused on C60 since it has unique properties. Much work has been carried out on it, such as the preparation of large quantities of C60, the structure studies of C60, the superconducting alkali-metal-C60 compounds, the growth of pure C60 single crystal. There is still a lot of work to do in detail, but because the size of the single ctystal is not large enough, there is some difficulty in research, for example, the electric and optical properties of the C60 single crystal.

关键词： C60 single crystal vapor phase growth conductance dielectric properties.

Friction and wear properties of copper matrix composites reinforced by tungsten-coated carbon nanotubes

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Rare Metals 2011年第6期30卷 657-663页

作者： NIE Junhui JIA Xian JIA Chengchang LI Yi ZHANG Yafeng SHI Na School of Materials science and Engineering University of Science and Technology Beijing Beijing 100083 China China Iron ＆ Steel Research institute Group Beijing 100081 China Journals Publishing Center University of Science and Technology Beijing Beijing 100083 China

Carbon nanotubes （CNTs） were coated by tungsten layer using metal organic chemical vapor deposition process with tungsten hexacarbonyl as a precursor. The W-coated CNTs （W-CNTs） were dispersed into Cu powders by magnetic stirring process and then the mixed powders were consolidated by spark plasma sintering to fabricate W-CNTs/Cu composites. The CNTs/Cu composites were fabricated using the similafprocesses. The friction coefficient and mass wear loss of W-CNTs/Cu and CNTs/Cu composites were studied. The results showed that the W-CNT content, interfacial bonding situation, and applied load could influence the friction coefficient and wear loss of W-CNTs/Cu com- posites. When the W-CNT content was 1.0 wt.%, the W-CNTs/Cu composites got the minimum friction coefficient and wear loss, which were decreased by 72.1% and 47.6%, respectively, compared with pure Cu specimen. The friction coefficient and wear loss of W-CNTs/Cu composites were lower than those of CNTs/Cu composites, which was due to that the interracial bonding at （W-CNTs）-Cu interface was better than that at CNTs-Cu interface. The friction coefficient of composites did not vary obviously with increasing applied load, while the wear loss of composites increased significantly with the increase of applied load.

关键词： carbon nanotubes tungsten layer copper friction coefficient wear loss

Lead-Zinc-Silver Metallogenic Prediction Based on Weights of Evidence Approach:A case Study in Tuotuohe Region,Qinghai,China

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地学前缘 2009年第S1期16卷 177-178页

作者： Yan Sun~(1,2.3.,Xunlian Wang~3.Jianping Chen~(1,2.3.,Qian Wang~(1,2.3. 1.institute of High and New Techniques Applied to Land Resources,China university of Geo{2.s(Beijing),Beijing 100083. China. 2.Beijing Key Laboratory of Development and Research for Land Resources Information,China university of Geo{2.s (Beijing),Beijing 100083.China 3.School of Earth {2.s and Resources,China university of Geo{2.s(Beijing) Beijing 100083.China

Tuotuo River region(E91°-E93.,N3.°-N 3.°) is located in southwest Qinghai Province,*** lies in one of the most important metallogenic belts in China—Northwest Sanjiang Metallogenic Belt,due to which Tuotuo River region can be of very high metal mineral potential not only in Qinghai Province but also *** this research,multisource data sets including geological,geochemical,geophysical, and remotely sensed images were integrated for mineral potential analysis with GIS *** the guidance of regional metallogenic features and deposit-forming geologic anomaly theories,evidential layers were obtained from these sets,which

关键词： Sanjiang metallogenic belt Tuotuo River lead-zinc-silver GIS Weights of Evidence minerogenic prediction