Plasma Nitriding of 722M24 Steel with Pure Lanthanum, Cerium and Neodymium as Sputter Sources

Ｓｉｎｃｅｔｈｅｉｎｉｔｉａｌｒｅｐｏｒｔｉｎｔｈｅｅａｒｌｙ 1 980ｓｔｈａｔｒａｒｅｅａｒｔｈａｄｄｉｔｉｏｎｈａｓａｃａｔａｌｙｔｉｃｅｆｆｅｃｔｏｎｔｈｅｇａｓｃａｒｂｏｎｉｔｒｉｄｉｎｇｐｒｏｃｅｓｓｏｆｓｔｅｅｌｓ[1] ,ａｌａｒｇｅａｍｏｕｎｔｏｆｗｏｒｋｈａｓｂｅｅｎｃｏｎｄｕｃｔｅｄｔｏｉｎ ｖｅｓｔｉｇａｔｅｔｈｅｉｎｆｌｕｅｎｃｅｏｆｒａｒｅｅａｒｔｈａｄｄｉｔｉｏｎｓｏｎｖａｒｉｏｕｓｔｈｅｒｍｏｃｈｅｍｉｃａｌｐｒｏｃｅｓｓｅｓ[2～ 8] .Ｉｔｈａｓｂｅｅｎｅｓｔａｂｌｉｓｈｅ…     

Adsorption of Er（ Ⅲ ） and Its Mechanism on Diglycolamidic Acid Resin

Ｔｈｅｓｙｎｔｈｅｓｉｓｃｈａｒａｃｔｅｒｉｚａｔｉｏｎａｎｄａｄｓｏｒｐ ｔｉｏｎｐｒｏｐｅｒｔｙｏｆｐｏｌｙｍｅｒｉｃｍａｔｅｒｉａｌｓｈａｖｅｂｅｅｎｐｕｂｌｉｓｈｅｄｉｎｒｅｃｅｎｔｙｅａｒｓ[1～ 9] .ＤｉｇｌｙｃｏｌａｍｉｄｉｃａｃｉｄｒｅｓｉｎＤＡＡＲｉｓａｎｏｖｅｌｐｏｌｙｍｅｒｉｃｍａｔｅｒｉａｌｗｈｉｃｈｃｏｎｔａｉｎｓａｆｕｎｃｔｉｏｎａｌｇｒｏｕｐ [-Ｎ(ＣＨ2 ＣＯＯＨ ) 2 ].Ｉｔｐｏｓｓｅｓｓｅｓｎｏｔｏｎｌｙｐｒｏｔｏｎｔｈａｔｃａｎｅｘｃｈａｎｇｅｗｉｔｈｃａｔｉｏｎ ,ｂ…     

Effect of Barium-Precursors on Reaction Kinetics in Y-Ba-Cu-O System

ＩｔｉｓｎｏｗｗｅｌｌｅｓｔａｂｌｉｓｈｅｄｔｈａｔｎｕｍｅｒｏｕｓｆａｃｔｏｒｓｉｎｆｌｕｅｎｃｅｔｈｅｒｅａｃｔｉｏｎｐａｔｈｗａｙｓｉｎｓｕｃｈａｃｏｍｐｌｉｃａｔｅｄＹ Ｂａ Ｃｕ Ｏｓｙｓｔｅｍ ,ｆｏｒｉｎ ｓｔａｎｃｅ ,ｔｈｅｃｒｙｓｔａｌｌｉｎｅｓｉｚｅｓａｎｄｔｈｅｒｅａｇｅｎｔ[1] ,ｔｈｅｄｅｇｒｅｅｏｆｍｉｘｉｎｇａｎｄｈｏｍｏ ｇｅｎｅｉｔｙ[2 ,3] ,ｔｈｅｏｘｙｇｅｎｐａｒｔｉａｌｐｒｅｓｓｕｒｅ[4～ 6 ] ,ａｓｗｅｌｌａｓｔｈｅｒｅａｃｔｏｒｓｉｚｅａｎｄｃｒｕｃｉｂｌｅｓｈａｐ…     

Effects of Cerium Nitrate on Expression of CaM Ⅰ and PMCA Ca~( 2 ) -ATPase mRNA in Rat Liver

ＣａｔｉｏｎｉｃｒａｄｉｕｓｏｆｒａｒｅｅａｒｔｈｅｌｅｍｅｎｔｓｉｓｃｌｏｓｅｔｏｔｈａｔｏｆＣａ2 .ＩｔｉｓｇｅｎｅｒａｌｌｙｓｕｇｇｅｓｔｅｄｔｈａｔｔｈｅｒｅｐｌａｃｅｍｅｎｔｏｆＣａ2 ｂｙＴｂ3 ｉｎｄｕｃｅｓｓｏｍｅａｌｔｅｒａｔｉｏｎｓｏｆｎａｔｉｖｅｓｔｒｕｃｔｕｒｅｏｆｃａｌｍｏｄ ｕｌｉｎ (ＣａＭ ) [1] ,ａｎｄｔｈｅｒｅｓｕｌｔｉｎｇｃｈａｎｇｅｓｉｎｂｉｏｌｏｇｉｃａｌｅｆｆｅｃｔｍａｙｂｅａｃａｕｓｅｏｆｔｏｘｉｃｉｔｙｏｆｒａｒｅｅａｒｔｈｓ[2 ] .Ｗａｎｇｅｔａｌ[3] ｆｏ…     

Visible-Light Excitated Photocatalytic Activity of Rare Earth Metal-Ion-Doped Titania

Ｔｉｔａｎｉｕｍｄｉｏｘｉｄｅｉｓｓｕｐｐｏｓｅｄｔｏｂｅｔｈｅｂｅｓｔｍａｔｅｒｉａｌｉｎｐｈｏｔｏｃａｔａｌｙｔｉｃａｃｔｉｖｉｔｙ ,ｓａｆｅｔｙ ,ｃｏｓｔａｎｄｓｔａｂｉｌｉｔｙ .Ｂｕｔｌａｒｇｅｂａｎｄ ｇａｐｅｎｅｒｇｙ(3 .2ｅＶ)ｆｏｒｂｕｌｋａｎａｔａｓｅＴｉＯ2 ｌｉｍｉｔｓｉｔｓｐｒａｃ ｔｉｃａｌａｐｐｌｉｃａｔｉｏｎｉｎｔｈｅｃａｓｅｏｆｎａｔｕｒａｌｓｏｌａｒｌｉｇｈｔ.Ａｔｐｒｅｓｅｎｔ ,ｖａｒｉｏｕｓｍｅｔｈｏｄｓ ,ｓｕｃｈａｓｉｏｎｉｍｐｌａｎｔａｔｉｏｎａｎｄｔｈｅｃｏ…     

Characterization and Preparation of Ce-Zr-O Solid Solution

ＣｅｒｉｕｍｏｘｉｄｅｗｉｔｈＣａＦ2 ｓｔｒｕｃｔｕｒｅｉｓｃｕｒ ｒｅｎｔｌｙｂｅｉｎｇｕｓｅｄａｓａｐｒｏｍｏｔｅｒｉｎｏｘｉｄａｔｉｏｎ .ＴｈｅｃａｐａｂｉｌｉｔｉｅｓｏｆｔｈｅｒｅｄｏｘｃｏｕｐｌｅＣｅ4 Ｃｅ3 ａｒｅｓｔｒｏｎｇｌｙｅｎｈａｎｃｅｄｉｆｏｔｈｅｒｅｌｅｍｅｎｔｉｓｉｎｔｒｏ ｄｕｃｅｄｉｎｔｏＣｅＯ2 ｌａｔｔｉｃｅｂｙｆｏｒｍｉｎｇｓｏｌｉｄｓｏｌｕ ｔｉｏｎ .ＳｅｖｅｒａｌａｐｐｒｏａｃｈｅｓｈａｖｅｂｅｅｎｕｓｅｄｔｏｐｒｅｐａｒｅＣｅＯ2 ＺｒＯ2 ｍｉｘｅｄｏｘｉｄｅ…     

Physico-Chemical Properties and Catalytic Behavior of LnSrNiO4 Mixed Oxides for NO Decomposition

ＰｈｙｓｉｃｏＣｈｅｍｉｃａｌＰｒｏｐｅｒｔｉｅｓａｎｄＣａｔａｌｙｔｉｃＢｅｈａｖｉｏｒｏｆＬｎＳｒＮｉＯ４ＭｉｘｅｄＯｘｉｄｅｓｆｏｒＮＯＤｅｃｏｍｐｏｓｉｔｉｏｎＺｈａｏＺｈｅｎ（赵震），ＹａｎｇＸｉａｎｇｇｕａｎｇ（杨向光），ＬｉｕＹｕ（...     

Effects of Concentration of La~(3 ) Vacancies in LaMnO_(3 λ) on the Catalytic Activity of Oxidation of CO

ＥｆｅｃｔｓｏｆＣｏｎｃｅｎｔｒａｔｉｏｎｏｆＬａ３＋ＶａｃａｎｃｉｅｓｉｎＬａＭｎＯ３＋λｏｎｔｈｅＣａｔａｌｙｔｉｃＡｃｔｉｖｉｔｙｏｆＯｘｉｄａｔｉｏｎｏｆＣＯＳｕｎＹｏｎｇａｎ（孙永安），ＺｈａｎｇＷｅｎｔａｏ（张文韬）（Ｄｅｐａｒｔｍｅｎ...     

Effects of La, Ce, Y and Tb ions on Free Radical Mediated Peroxidation of Human Erythrocyte Membrane

Ｂａｓｅｄｏｎｔｈｅｈｅｐａｔｉｃｃｏｎｔｅｎｔｓｏｆｌｉｐｉｄｐｅｒ ｏｘｉｄｅｓａｆｔｅｒ 0 0 5ｍｇ·ｋｇ-1ｂｏｄｙｗｅｉｇｈｔ(ｂｗ)ｏｆＳｍＣｌ3ａｎｄＰｒＣｌ3ｗｅｒｅｇｉｖｅｎｂｙｐ .ｏ ,ｉ .ｐａｎｄｉ.ｖｉｎｊｅｃｔｉｏｎｔｏｔｈｅｒａｔｓｄａｉｌｙｆｏｒ 1 2ｄ ,Ｎｉｅｅｔａｌ[1] ｆｏｕｎｄｔｈａｔｔｈｅｙｂｏｔｈｉｎｈｉｂｉｔｅｄｔｈｅｌｉｐｉｄｐｅｒｏｘｉｄａｔｉｏｎａｎｄｅｌｅｖａｔｅｄｔｈｅＳＯＤａｃｔｉｖｉｔｙ .Ｈｏｗｅｖｅｒ,ａｈｉｇｈｅｒｄｏｓｅ (2 8ｍｍｏｌ·ｋｇ-1)ｏｆＬ…     

Effect of CeO_2 on Crystal Structures and Catalytic Properties of the Mn_2O_3 Catalysts

ＥｆｆｅｃｔｏｆＣｅＯ_２ｏｎＣｒｙｓｔａｌＳｔｒｕｃｔｕｒｅｓａｎｄＣａｔａｌｙｔｉｃＰｒｏｐｅｒｔｉｅｓｏｆｔｈｅＭｎ_２Ｏ_３ＣａｔａｌｙｓｔｓＬｕｏＭｅｎｇ－Ｆｅｉ（罗孟飞）；ＺｈｕＢｏ（朱波）；ＹｕａｎＸｉａｎ－Ｘｉｎ（袁贤鑫）（Ｃａｔａｌｙ...     

Preparation, Characterization of CuO／CeO2 and Cu／CeO2 Catalysts and Their Applications in Low-Temperature CO Oxidation

CeO2 was synthesized via sol-gel process and used as supporter to prepare CuO/CeO2, Cu/CeO2 catalysts by impregnation method. The catalytic properties and characterization of CeO2, CuO/CeO2 and Cu/CeO2 catalysts were examined by means of a microreactor-GC system, HRTEM, XRD, TPR and XPS techniques. The results show that CuO has not catalytic activity and the activity of CeO2 is quite low for CO oxidation. However, the catalytic activity of CuO/CeO2 and Cu/CeO2 catalysts increases significantly. Furthermore, the activity of CuO/CeO2 is higher than that of Cu/CeO2 catalysts.     

CuO／CeO2 Catalysts for Selective Oxidation of Carbon Monoxide in Excess Hydrogen

CuO/CeO2 catalysts were prepared by a coprecipitation method and tested for CO removal from reformed fuels via selective oxidation. The influence of the calcination temperature on the chemical compositions and catalytic performance of CuO/CeO2 catalysts were studied. It was found that CuO/CeO2 catalysts exhibit excellent CO oxidation activity and selectivity, and the complete removal of CO is attained when the catalysts are calcined at appropriate temperatures. XRD, TPR and XPS results indicate that CuO/CeO2 catalysts exhibit higher catalytic performance in CO selective oxidation due to the strong interaction between copper oxide and cerium dioxide, which promotes the dispersion and hydrogen reduction activity of copper.     

Effect of yttrium addition on water-gas shift reaction over CuO/CeO2 catalysts

This paper presented a study on the role of yttrium addition to CuO/CeO2 catalyst for water-gas shift reaction. A single-step co-precipitation method was used for preparation of a series of yttrium doped CuO/CeO2 catalysts with yttrium content in the range of 0-5wt.%. Properties of the obtained samples were characterized and analyzed by X-ray diffraction (XRD), Raman spectroscopy, H2-TPR, cyclic voltammetry (CV) and the BET method. The results revealed that catalytic activity was increased with the yttrium content at first, but then decreased with the further increase of yttrium content. Herein, CuO/CeO2 catalyst doped with 2wt.% of yttrium showed the highest catalytic activity (CO conversion reaches 93.4% at 250℃) and thermal stability for WGS reaction. The catalytic activity was correlated with the surface area, the area of peak y of H2-TPR profile (I.e., the reduction of surface copper oxide (crystalline forms) interacted with surface oxygen vacancies on ceria), and the area of peak C2 and A1 (Cu0→Cu2+ in cyclic voltammetry process), respectively. Besides, Raman spectra provided evidences for a synergistic Cu-Ovacancy interaction, and it was indicated that doping yttrium may facilitate the formation of oxygen vacancies on ceria.     

Structure and Catalytic Behavior of CuO-ZrO-CeO2 Mixed Oxides

The effect of doping CuO on the structure and properties of zirconia-ceria mixed oxide was studied. The results show that addition of CuO decreases the reduction temperature of ceria, and stabilizes the cubic structure of mixed oxides, and enhances catalytic activity of CuO-ZrO-CeO2 mixed oxides for CO oxidation. Increasing ceria content in the mixed oxides can enhance the catalytic activity, but some impurities such as sulfate make catalytic activity falling. There is little effect of calcination temperature on catalytic activities, implying that these catalysts are effective with good thermal stability.     

Effect of water vapor on the CO and CH4 catalytic oxidation over CeO2-Mox (M=Cu,Mn,Fe,Co,and Ni) mixed oxide

CeO2-MOx (M=Cu, Mn, Fe, Co, and Ni) mixed oxide catalysts were prepared by a citric acid complexation-combustion method. CeO2-MOx solid solutions could be formed with M cations doping into CeO2 lattice, while NiO and Co3O4 phases were detected on the surface of CeO2-NiO and CeO2-Co3O4 by Raman spectroscopy. The presence of M in CeO2 could obviously promote its catalytic activity for CH4 catalytic combustion and CO oxidation. Among the prepared samples, CeO2-CuO exhibited the best performance for CO oxidatio...     

Influence of cobalt on performance of Cu-CeO_2 catalysts for preferential oxidation of CO

Copper and cobalt oxides supported on CeO_2 were investigated for preferential oxidation of carbon monoxide(CO-PROX) in the presence of excess hydrogen and CO_2.(Cuo)_(1-x)(Co_3 O_4)_(x/3)-(CeO_2)_(2.5)(x=0,0.25,0.50,0.75,0.85 and 1) catalysts were prepared by coprecipitation method.These mixed oxide catalysts were characterized by several physicochemical techniques,such as BET surface area(S_(BET)),X-ray diffraction(XRD),high resolution transmission electron microscopy(HRTEM),temperature programmed reduction(TPR) and X-ray photoelectron spectroscopy(XPS).XRD studies show the peaks related to CuO and Co_3 O_4 phases in copper and cobalt containing CeO_2 catalysts.The average particle size of the CeO_2 crystallites is in the range of 8-10 nm as evaluated from HRTEM studies.XPS studies demonstrate that Cu,Co and Ce in(cuO)_(1-x)(Co_3O_4)_(x/3)-(CeO_2)_(2.5) catalysts are presented in+2 and +1,+3 and +2 and +4 and +3 oxidation states,respectively.The catalyst with x=0.75 shows better activity and selectivity towards CO-PROX.Though the catalyst with only copper(CuO-CeO_2,x=0) shows good activity but reverse water gas shift(RWGS) reaction is noticed at high temperature.On the other hand,RWGS reaction is suppressed on the cobalt containing CuO-ceO_2 catalyst.Cobalt on CeO_2 with x=1 shows hardly any activity for PRoX reaction at low temperatures.No methanation activity is observed on CuO-CeO_2 or Co_3O_4-CeO_2 catalysts.In contrast,combination of copper and cobalt on CeO_2 shows methanation of CO where enhanced activity is observed with increasing in cobalt content.     

La-Ce-Cu复合金属氧化物的结构表征及催化性能

本文用ＮＨ４ＮＯ３共熔法合成Ｌａ－Ｃｅ－Ｃｕ系列样品。用ＸＲＤ分析了ＣｅＯ２在铜酸镧盐中的溶解度,发现大量ＣｅＯ２存在时,Ｌａ２Ｏ３、ＣｕＯ的加入导致原晶体结构发生变形,生成少量铜酸镧盐。ＸＲＦ分析了系列样品组成均为氧缺陷型化合物。ＸＰＳ研究发现,含大量ＣｅＯ２的样品高温焙烧后在ＣｅＯ２表面生成复合金属氧化物Ｌａ２ＣｕＯ４,最表面一层为少量Ｌａ２Ｏ３,并确定了其中Ｏ的属性。利用ＴＥＭ研究了部分样品的表面结构,同时研究了其ＣＯ催化氧化活性。     

Valence State of Active Copper in CuOx/CeO2 Catalysts for CO Oxidation

CuOx/CeO2 catalysts were prepared by adsorption-impregnation method, CO conversion was tested over the catalysts pretreated under different conditions for preferential CO oxidation in H2, and the catalysts were characterized with X-ray photoelectron spectroscopy and temperature programmed reduction. Experimental results show that there are two kinds of copper, which are Cu^＋ and Cu^2＋ in calcined CuOx/CeO2, Among them, the Cu^＋ is the key active component for CO oxidation. The main reason is as follows： CO is activated by copper for CO oxidation over CuOx/CeO2, while CO can not be activated by Cu^2＋. Only when Cu^2＋ is reduced to Cu ^＋ or Cu^0, the copper may be active for CO oxidation, moreover, the experimental results show that the reduction of Cu^2＋ does not lead to an increase of catalytic activity. So the active species is Cu^＋ in CuOx/CeO2 catalysts.     

Synthesis of mesoporous CeO2-MnOx binary oxides and their catalytic performances for CO oxidation

Mesoporous CeO2-MnOx binary oxides with different Mn/Ce molar ratios were prepared by hydrothermal synthesis and characterized by scanning electron microscopy （SEM）, N2 sorption, X-ray diffraction （XRD）, X-ray photoelectron spectroscopy （XPS） and H2 temperature-programmed reduction （H2-TPR）. The characterization results indicated that the CeO2-MnOx catalysts exhibited flower-like microspheres with high specific surface areas, and partial Mn cations could be incorporated into CeO2 lattice to form solid solution. The CeO2-MnOx catalysts showed better catalytic activity for CO oxidation than that prepared by the coprecipitation method. Furthermore, the CeO2-MnOx catalyst with Mn/Ce molar ratio of 1 in the synthesis gel （Ce-Mn-1） exhibited the best catalytic activity, over which the conversion of CO could achieve 90% at 135 ℃. This was ascribed to presence of more Mn species with higher oxida- tion state on the surface and the better reducibility over the Ce-Mn-I catalyst than other CeO2-MnOx catalysts.     

Preparation,characterization and catalytic oxidation property of CeO2/Cu2+-attapulgite （ATP） nanocomposites

Cerium oxide(CeO2) coated on copper modified attapulgite clay nanocomoposite(CeO2/Cu2+-ATP) was prepared by homogeneous deposition method.The microstructures of the as-prepared CeO2/Cu2+-ATP nanocomposites were characterized by X-ray diffraction(XRD),energy-dispersive spectrometer(EDS) and transmission electron microscopy(TEM).The results indicated that CeO2 particles with average size of about 5 nm were loaded onto the Cu2+-ATP and were widely dispersed.Comparing the catalytic activity of ATP/CeO2 and CeO2/Cu2+-ATP,the catalytic activity was improved when a small quantity of Cu2+ was introduced.The loading amount of CeO2 and reaction temperature had important effects on decolorization ratio of methyl orange(MO).When the loading amount and reaction temperature were 70% and 338 K,respectively,the decolorization ratio of MO reached over 99%,which showed excellent catalytic activity.