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Wear Performance of Laser Surface Hardened GCr15 Steel

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Journal of Wuhan University of Technology(Materials science) 2010年第1期25卷 84-88页

作者：雷声 School of Materials science and Engineering Hefei University of Technology department of Electromechanical Engineering Anhui Institute of Architecture and Industry

In order to assess the new tribological properties of laser surface hardened GCr15 steel, the wear resistance between specimens treated with laser and those of conventionally hardened under dry sliding conditions was compared. The change of wear mechanisms in laser hardened GCr15 resulted in a distinct difference in wear rates. The results showed that quenched zones not only had sufficient depth of hardening and higher hardness, but had more retained austenite and finer carbides because of a higher degree of carbide dissolution. Laser surface hardened GCr15 steel specimens exhibited superior wear resistance to their conventionally hardened specimens due to the effects of the microstructure hardening, high hardness and toughness. The wear mechanism for both the laser quenched layer and conventionally hardened layer was highly similar, generally involving adhesive, material transfer, wear-induced oxidation and plowing. When conventionally hardened block specimens rubbed against the laser hardened specimens, the surface of conventionally hardened block specimens was polished. The microstructural thermal stability was increased after laser surface treatment.

关键词： laser hardening dry sliding conditions GCr15 steel wear mechanisms

Reduction and Coupling Reaction of Carbonyl Compounds by Aluminum Powder and a Small Amount of Oxalic Acid in Water

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Chinese Journal of Chemistry 2006年第1期24卷 141-145页

作者：袁仕祯汪志勇李真 department of Material science and Engineering Anhui Institute of Architecture and Industry Hefei Anhui 230022 China department of Chemistry University of Science and Technology of China Hefei Anhui 230026 China

A convenient pinacol coupling of aromatic aldehydes and aryl methyl ketones has been achieved with high yields by aluminum powder in the presence of oxalic acid in water. However, the diastereoselectivities of pinacols were not satisfying, and most aliphatic aldehydes and diaryl ketones have been found to be unreactive under the same conditions.

关键词： aluminum mediator pinacol coupling reaction aqueous media

A novel technology for quick acclimation of an anaerobic microbial consortia used for biodegrading teraphthalic acid (TA)

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Journal of Environmental sciences 2002年第2期14卷 204-209页

作者： LI Xiao ming ZENG Guang-ming CHEN Jian LUN Shi yi department of Environmental science and Engineering Hunan UniversityChangsha 410082China School of Biotechnology Wuxi University of Light IndustryWuxi 214036China

The seed sludge originated from a methane fermentation reactor was enriched and acclimated with TA as sole carbon source under nitrate respiration mode first for 6 week, and then can be turned to methane fermentation conditions. After 6 weeks processing, the specific rate of TA degradation under nitrate respiration mode reached 23.8 mgTA/(L·gVSS), more than two times of that under methane fermentation mode 11.4 mg TA/(L·gVSS). The TA reductive cleavers' population density increased about 6 times and 20 times after 30 days and 90 days acclimation. After a total of 90 days for the enrichment and acclimation, the fermentative bacteria which originally existed in the seed sludge nearly disappeared, and instead of them, the TA reductive and cleaving bacteria group was formed in the new consortia, which was confirmed by the MPN counts and roll tube counts. Compared with the control experiment, the acclimation period can be shortened by about 50%.

关键词： acclimation anaerobic sludge enrichment nitrate terephthalic acid (TA)

Conformal optical design with combination of static and dynamic aberration corrections

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Chinese Physics B 2009年第2期18卷 565-570页

作者：李岩李林黄一帆刘家国 department of Optoelectronic Engineering Beijing Institute of Technology 207 Institute of China Aerospace science & industry Corporation 50 Yongding Road Haidian District

Conformal domes that are shaped to meet aerodynamic requirements can increase range and speed for the host platform. Because these domes typically deviate greatly from spherical surface descriptions, a variety of aberrations are induced which vary with the field-of-regard （FOR） angle. A system for correcting optical aberrations created by a conformal dome has an outer surface and an inner surface. Optimizing the inner surface is regard as static aberration correction. A deformable mirror is placed at the position of the secondary mirror in the two-mirror all reflective imaging system, which is the dynamic aberration correction. An ellipsoidal MgF2 conformal dome with a fineness ratio of 1.0 is designed as an example. The FOR angle is 0°-30°, and the design wavelength is 4μm. After the optimization at 7 zoom positions by using the design tools Code V, the root-mean-square （RMS） spot size is reduced to approximately 0.99 to 1.48 times the diffraction limit. The design results show that the performances of the conformal optical systems can be greatly improved by the combination of the static correction and the dynamic correction.

关键词： conformal domes Zernike polynomial surface deformable mirror aberration correction

Magnetic properties of rare earth HoCrO_3 chromites

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Journal of Rare Earths 2011年第11期29卷 1060-1065页

作者：苏玉玲张金仓冯振杰李子炯沈岩曹世勋 department of Physics Zhengzhou University of Light Industry department of Physics Shanghai University

The temperature dependence of the magnetic properties was systemically studied by dc/ac magnetization and specific heat measurement for heavy rare earth HoCrO3 *** results revealed the existence of complex phase coexistence and competitive magnetic behavior in HoCrO3 *** was found that,in the region of higher temperature above 141.0 K,HoCrO3 behaved as a typical Curie-Weiss paramagnetic（PM）.And in the region of low temperature,a novel magnetization behavior was observed with negative magnetization（diamagnetism-like） characteristics under an external field of 100 Oe and M-T curves exhibited two symmetrical branches for field cooling（FC） and zero field cooling（ZFC） *** behavior indicated the coexistence of canted antiferromagnetic（CAFM） and weak ferromagnetic（FM） *** also exhibited the existence of competition mechanism below characteristic temperature TN1=141.0 K and the magnetic order of Ho ion below 7.5 *** current complex magnetization might be attributed to the interaction between paramagnetic Ho3＋ moments and canted Cr3＋ moments.

关键词： rare earth chromites phase coexistence magnetic interaction

Effect of Ho-doping on photocatalytic activity of nanosized TiO_2 catalyst

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Journal of Rare Earths 2008年第1期26卷 71-75页

作者：蔡河山刘国光吕文英黎晓霞余林李大光 department of Resource and Environment Foshan University Faculty of Environmental science and Engineering Faculty of Chemical Engineering and Light industry Guangdong University of Technology

Ho-doped TiO2 nanoparticles with higher photocatalytic activity were prepared by an acid-catalyzed sol-gel method. The photocatalytic decomposition of methyl orange in aqueous solution was used as a probe reaction to evaluate their photocatalytic activities. The effects of Ho doping on the crystallite sizes, crystal pattern, surface composition, and optical property of the catalysts were investigated by means of techniques such as X-Ray Diffraction （XRD）, Transmission Electron Microscopy （TEM）, Diffuse Reflectance UV-Vis Spectroscopy （UV-Vis DRS）, Fourier Transform Infrared （FT-IR）, and Photo-Luminiscence （PL） spectra. Moreover, the modification mechanism of Ho doping was also discussed. The results showed that Ho doping could inhibit phase transformation from anatase to rntile, suppress the growth of TiO2 grains, cause blue shift of the absorption spectrum edge, accelerate surface hydroxylation, and enhance the separation efficiency of photoinduced electron-hole pairs, which resulted in a significant improvement in the photoreactivity of Ho-doped TiO2. Among them, the Ho-doped TiO2 calcined at 500℃ achieved the highest photocatalytic activity.

关键词： titanium dioxide Ho-doping characterization photocatalysis methyl orange rare earths

Hydrogen Storage in Benzene Moiety Decorated Single-Walled Carbon Nanotubes

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Chinese Physics Letters 2006年第6期23卷 1536-1539页

作者：张丙云梁其民宋晨夏曰源赵明文刘向东张红雨 School of Physics and Microelectronics Shandong University Jinan 250100 department of Mathematical and Physical science Shandong Institute of Light Industry Jinan 250100

The hydrogen storage capacity of （5, 5） single-walled carbon nanotubes （SWNTs） decorated chemically with benzene moieties is studied by using molecular dynamics simulations （MDSs） and density functional theory （DFT） calculations. It is found that benzene molecules colliding on （5, 5） SWNTs at incident energy of 50eV form very stable configurations of benzene moiety adsorption on the wall of SWNTs. The MDSs indicate that when the benzene moiety decorated （5, 5） SWNTs and a pristine （5, 5） SWNT are put in a box in which hydrogen molecules are filled to a pressure of ～26 atm, the hydrogen storage capacity of the benzene moiety decorated （5, 5） SWNT is about 4.7wt.% and that of the pristine （5, 5） SWNT is nearly 3.9wt.%.

关键词： NANOSTRUCTURES CAPACITY

Facile preparation of Fe-Y catalyst under water-free conditions for selective catalytic reduction of NO_x by ammonia

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science China Chemistry 2013年第10期56卷 1478-1484页

作者： ZHANG ZeKai ZHANG BinHao LIU HuaYan CHEN YinFei department of industry Catalysis Zhejiang University of Technology

A series of Fe-Y zeolite catalysts with different Fe loading were prepared by ferrocene sublimation under solvent and wa- ter-free conditions. The dispersion, structure and morphology of the iron species on the Fe-Y catalysts were characterized by XRD, TEM and UV-Vis. The catalytic activities of Fe-Y samples were measured in selective catalytic redaction of NO with ammonia （NH3-SCR）. The results showed that the iron species on the HY zeolite support were mainly made up of isolated Fe3＋ ions, FexOy oligomers and a little amount of 〈 3 nm spherical Fe203 particles. Isolated Fe3＋ ions are predominating among all the Fe-Y catalysts. The sum of isolated Fe3＋ ions and FexOy oligomers took up more than 90% percent of total iron species on the Fe-Y till 10.0 wt% loading of Fe.

关键词： SCR NOx ferrocene Fe-Y water-free

Integrated Rock Typing of the grainstone Facies in a Sequence Framework：a Case from the Jurassic Arab Formation in the Persian Gulf

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Acta Geologica Sinica(English Edition) 2018年第4期92卷 1432-1450页

作者： Ali ASSADI Hossain RAHIMPOUR-BONAB Rahim KADKHODAIE-ILKHCHI Research Institute of Petroleum industry (RIPI) Tehran Iran School of Geology College of Science University of Tehran Tehran Iran department of Earth science Faculty of Natural Science University of Tabriz Iran

The late Jurassic Arab Formation, a significant carbonate-evaporite reservoir rock in the Persian Gulf, is characterized by frequent grainstone facies. For rock type identification and reservoir characterization, core description, petrographic studies and pore system evaluation are integrated for Balal oil field in the Persian Gulf. The grainstone facies are developed into three shoal subenvironments on a carbonate ramp platform： leeward, central and seaward. Compaction, dissolution, cementation, anhydrite mineralization and dolomitization are the main diagenetic processes affecting the depositional pore system. Considering depositional and diagenetic features and pore types, the grainstones are classified into six rock types （RT 1 to RT6）. Rock types 1, 2 and 5 have large pore throat sizes with inter- granular and touching vug pore types. In rock type 3, moldic pores lead to high porosity and low permeability. Rock types 4 and 6 are cemented by anhydrite, calcite and dolomite. Generally, RTs 1, 2, 3 and 5 are related to late Transgressive systems tract （TST） and early Highstand systems tracts （HST） and show fair to good reservoir quality. In contrast, RTs 4 and 6 of late HST system tract show lower poroperm values, due to evaporite mineralization. Characterization of the grainstone facies provides a comprehensive understanding of the reservoir zones of the Arab Formation.

关键词： grainstone facies pore system rock type reservoir quality Arab Formation Kimmeridgian-Tithonian Iran