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Effect of activation agents on the surface chemical properties and desulphurization performance of activated carbon

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science china(Technological sciences) 2010年第9期53卷 2515-2520页

作者： ZHANG XiangLan,ZHANG Yan,WANG ShuangSheng,ZHANG JingJing & ZHOU Wei School of Chemical and Environmental engineering,china university of Mining and Technology (beijing),beijing 100083.china School of Chemical and Environmental engineering China University of Mining and Technology (Beijing) Beijing China

Flue gas pollution is a serious environmental problem that needs to be solved for the sustainable development of *** surface chemical properties of carbon have great influence on its desulphurization performance.A series of activated carbons (ACs) were prepared using HNO3,H2O2,NH3·H2O and steam as activation agents with the aim to introduce functional groups to carbon surface in the ACs preparation *** ACs were physically and chemically characterized by iodine and SO2 adsorption,ultimate analysis,Boehm titration,and temperature-programmed reduction (TPR).Results showed that the iodine number and desulphurization capacity of NH3·H2O activated carbon (AC-NH3) increase with both activation time,and its desulphurization capacity also increases with the concentration of activation ***,HNO3 activated carbon (AC-HNO3) and H2O2 activated carbon (AC-H2O2) exhibit more complex *** their iodine numbers increase monotonously with activation *** with steam activated AC (AC-H2O),the nitrogen content increases 0.232% in AC-NH3 and 0.077% in *** amount of total basic site on AC-HNO3 is 0.19 mmol·g-1 higher than that on AC-H2O.H2O2 activation introduces an additional 0.08 mmol·g-1 carboxyl groups to AC surface than that introduced by steam *** desulphurization capacity of ACs in simulate flue gas desulphurization decreases as follows: AC-NH3 > AC-HNO3 > AC-H2O2 > *** sequence is in accord with the SO2 catalytic oxidation/oxidation ratio in the absence of oxygen and the oxidation property reflected by *** the presence of oxygen,all adsorbed SO2 on ACs can be oxidized into *** desulphurization capacity increases differently according to the activation agents;the desulphurization capacity of AC-NH3 and AC-HNO3 improves by 4.8 times,yet AC-H2O increases only by 2.62 as compared with the desulphurization of corresponding ACs in absence of oxygen.

关键词： activated carbon activation agent surface chemical property desulphurization TPR

Synthesis and Characterization of Sm_xGd_yCe_(1-x-y)O_(2-δ) Nanopowders

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Journal of Materials science & Technology 2005年第1期21卷 131-134页

作者： Xiwen SONG, Yongwang ZHAO, Zhefeng WANG, Jun PENG,Wenguang ZHAO and Shengli AN School of Materials science and engineering, Inner Mongolia university of science and Technology, Baotou 014.10, {4. School of Metallurgical and Ecological engineering, university of science and Technology beijing, beijing 100083. {4.Assoc. Prof. Sch. of Mat. Sci. and Eng. Inner Mongolia Univ. of Sci. Baotou 014010 China Sch. of Metall. and Ecological Eng. Univ. of Sci. and Technol. Beijing Beijing 100083 China

SmxGdyCe1-x-yO2-δ (x+y=0.2 and x=0, 0.04. 0.08, 0.12, 0.16, 0.2) nanopowders were prepared by a copre-cipitation method. The zeta potential and sedimentation volume of Ce(OH)4.aqueous dispersions at different pH values were measured. The isoelectric point (IEP) of Ce(OH)4.suspensions is 7.0. The maximum potential value of -18.5 mV and maximum sedimentation volume of 19 ml are reached at pH=10. The evolution behaviors of the xSm(OH)3·yGd(OH)3·(1-x-y)Ce(OH)4.dried powders in the heating process was characterized by DTA/TG and XRO. The powders decompose to ceria based solid solution at a temperature below 300℃ and forms cubic fluorite structure ceria at about 650℃. The properties of SmxGdyCe1-x-yO2-δ solid solutions were characterized by XRD, TEM and BET. The lattice parameter of doped Ce02 increases linearly with increasing Sm3+ substitution (or decreasing Gd3+ substitution). The particle size of the doped ceria powders is from 5 nm to 10 nm.

关键词： Coprecipitation Sm2O3 Gd2O3 Doped Ceria Nano-powders

XPS Studies of Magnetic Multilayers

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Journal of university of science and Technology beijing 2001年第3期8卷 210-213页

作者： Guanghua Yu, Hongchen Zhao, Jiao Teng, Chunlin Chai, Fengwu Zhu, Yang Xia, Shumin Chai Material science and engineering School, university of science and Technology {4., {4. 100083. china Microelectronics Center, Chinese Academy of science, Beijin Material science and Eng. School Univ. of Sci. and Technol. Beijing Beijing 100083 China

NiOx/Ni81Fe19 and Co/AlOx/Co magnetic multilayers were fabricated by reactive RF/DC magnetron sputtering on clean glass substrates and oxidized Si (100) substrates, respectively. The exchange biasing field (H-ex) between NiO4.and Ni81Fe19 as a function of NiOx oxidation states was studied by X-ray photoelectron spectroscopy (XPS). The oxidation states and the oxide thickness of Al layers in magnetic multilayer films consisting of Co/AlOx/Co were also analyzed. It is found that the H-sr of NiOx/Ni81Fe19 films only depends on Ni2+ but not on Ni3+ or Ni. The bottom Co can be completely covered by depositing an A I layer thicker than 2.0 nm. The oxide layer was Al2O3, and its thickness was 1.15 mn.

关键词： NiOx exchange biasing field H-ex AlOx X-ray photoelectron spectroscopy (XPS)

Cathodic micro-arc electro-deposition of ZrO_2 coatings in an aqueous solution containing colloidal particles

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Rare Metals 2002年第3期21卷 198-202页

作者： YANGXiaozhan GAOWei 等 beijingKeyLaporatoryforCorrosion ErosionandSurfaceTechnologyUniversityofScienceandTechnologyBeijingBeijing100083China Schoolofengineering TheUniversityofAucklandNewZealand

By a novel technique-cathodic micro-arc electro-deposition (CMED), ZrO_2coatings were deposited on an FeCrAl alloy. Experimental results show that the necessary conditionsfor obtaining ZrO_2 coatings are to apply a pulse peak voltage over a critical value and addmoderate amounts of ZrO_2 colloidal particles and Zr(NO_3)_4.in the aqueous solution. Theas-deposited coatings are porous because hydrogen, water, and other vapors are generated andreleased from the coatings to the solution during the spark reaction. The coatings containmonoclinic and tetragonal crystalline ZrO_2 with certain degree of amorphous structure. Theprocessing parameters and mechanism of CMED were discussed.

关键词： cathodic micro-arc electro-deposition ZrO_2 coating FeCrAl alloy

Analysis and simulation of high strain compression of anisotropic open-cell elastic foams

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science china(Technological sciences) 2010年第3期53卷 863-869页

作者： LU ZiXing,HUANG JiXiang&CHEN Xin School of Aeronautic science and engineering,beijing university of Aeronautics and Astronautics,beijing 100191,china School of Aeronautic science and engineering Beijing University of Aeronautics and Astronautics Beijing China

By elongating the regular Kelvin model in one direction and keeping unchanged in the other two directions,the anisotropic model was ***,the simplified periodic structural cell was obtained according to the periodicity and symmetry of the model in the whole *** the half-strut element and elastic deflection theory to analyze the mechanical behavior as were adopted in the previous studies,this paper obtained the theoretical expressions for the compressive stress and strain as well as the corresponding curves in the rise and transverse *** addition,the theoretical results were examined by the finite element *** indicated that the theoretical analysis was very close to the finite element simulation when the strain was not too high,which confirmed the validity of theoretical *** the same time,the anisotropy was shown to have a significant effect on the mechanical properties of open-cell *** the anisotropy ratio increased,the compressive stress was improved in the rise direction but dropped in the transverse direction under the same strain.

关键词： open-cell foams elastic deformation Kelvin model anisotropy finite element

Taurine inhibits ischemia/reperfusion-induced compartment syndrome in rabbits

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Acta Pharmacologica Sinica 2005年第7期26卷 821-827页

作者： Ji-xian WANG~(2,3) Yan LI~2 Li-ke ZHANG~4.Jing ZHAO~5 Yong-zheng PANG~(2,3) Chao-shu TANG~(3,5) Jing ZHANG~(2,3,6) 1 Institute of Cardiovascular Disease Research,The First Hospital of Peking university,beijing 100034.china 3 Key Laboratory of Molecular Cardiovascular science,Ministry of Education,beijing 100083.china 4.Department of Pathophysiology,Capital Institute of Medicine,beijing 100054.china 5 Department of Physiology Health Center of Medical sciences,Peking university,beijing 100083.china Institute of Cardiovascular Disease Research The First Hospital of Peking University Beijing China Key Laboratory of Molecular Cardiovascular science Ministry of Education Beijing China Department of Pathophysiology Capital Institute of Medicine Beijing China Department of Physiology Health Center of Medical Sciences Peking University Beijing China

Aim:To investigate effects of taurine on ischemia/reperfusion(I/R)-induced com-partment syndrome in rabbit hind ***:Rabbits underwent femoralartery occlusion after ligation of branches from terminal aorta to femoral *** a 7-h ischemia,reperfusion was established with the use of heparinizedpolyethylene *** received taurine(1 g/kg)or normal saline(control)by iv infusion 10 min before shunt *** reperfusion,anterior com-partment pressure(ACP)was monitored continuously in the left lower *** muscle triphenyltetrazolium chloride(TTC)level,taurine contentand myeloperoxidase activity were *** stress was induced in thein vitro gastrocnemius muscle slices by free radical generating systems(FRGS),and the malondialdehyde content was measured in presence or absence of ***:After 7 h of ischemia,none of the parameters that we measured weredifferent from those before ischemia,except that TTC reduction decreased by80%.In the control group,after 2 h of reperfusion,ACP increased 4.5-fold,andgastrocnemius muscle taurine content was reduced by 33%.In taurine-treatedanimals,at 2 h reperfusion,the mean arterial blood pressure and heart rate wereincreased,by 6% and 10%.ACP decreased by 39%,muscle edema decreased by16%,TTC reduction increased by 150%,and lactate dehydrogenase decreased by36% compared to control *** and muscle taurine content increased by70% and 88%,*** the taurine-treated group,at 2 h repeffusion,plasmamalondialdehyde and conjugated diene content were decreased by 38% and 23%,respectively,and muscle malondialdehyde and conjugated diene content decreasedby 22% and 30%,respectively compared to the control *** 2 h reperfusion,myeloperoxidase activity was increased 3.5-fold in control *** the in vitrostudy,taurine decreased malondialdehyde content in muscle slices incubatedwith hypochlorous acid in a dose-dependent manner,but there was no changewhen incubated

关键词： taurine compartment syndromes reperfu sion injury

Phase relationship of complex multi-component system in chromate cleaner production

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Progress in Natural science:Materials International 2007年第7期17卷 845-850页

作者： Ge Xinlei~1 Wang Xidong~(1,3**) Zheng Shili~2 Zhang Mei~1 Zhang Yi~2 (1.Department of Physical Chemistry,university of science and Technology beijing,beijing {4.china 2.Institute of Process engineering,Chinese Academy of sciences,beijing 100080,china 3.College of engineering,Peking university,beijing 100871,china) Department of Physical Chemistry University of Science and Technology Beijing Beijing 100083 China College of engineering Peking University Beijing 100871 China Institute of Process engineering Chinese Academy of Sciences Beijing 100080 China

The phase relationships of the complex multi-component systems in the liquid-phase oxidization and separation process related with the chromate cleaner production are investigated theoretically and *** phase diagram of main system Fe- Cr2O4.KOH-O2of oxidization process and the relationship of its standard Gibbs free energy change with temperature are calculated.A se- ries of phase diagrams of the separation process at different temperatures,such as K（Na）OH-K（Na）2CrO4.H2O,KOH-KAlO2-H2O, K（Na）OH-K（Na）2CO3-H2O,K（Na）OH-K（Na）HCO3-H2O and K（Na）HCO3-K（Na）2CrO4.H2O have also been *** ex- periments are carried out to verify the calculated *** results showed that the sub-molten salt media are suitable for the oxidization and separation processes;FeCr2O4.an be oxidized across a wide range of temperature;K（Na）2CrO4.an be separated from K（Na）AlO2system at appropriate temperature and proper concentration;the crystallization of carbonate is easier than that of K（Na）2CrO4.

关键词： chromite chromate system thermodynamics calculation phase diagram

THEORETICAL ANALYSIS AND EXPERIMENTAL VERIFICATION ON TERNARY-WAVES METHOD TO COMPILE ACCELERATED SPECTRA

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Chinese Journal of Mechanical engineering 2002年第4期15卷 308-313页

作者： Xiong Junjiang Wu Zhe Gao ZhentongAircraft Design Bureau, beijing university of Aeronautics and Astronautics,beijing 100083. {4. Aircraft Design Bureau Beijing University of Aeronautics and Astronautics 北京 100083

The equivalent damage calculation formulae of fatigue crack formation andgrowth are established. In order to compile the fatigue crack formation and growth accelerated loadspectra, the main wave shapes and load sequence of the actual load spectrum are kept constant, andthe carrier waves are cut off. And secondary waves are put together into new secondary waves toshorten the test time according to the equivalent damage calculation formulae respectively. Then bythe fatigue cumulative damage calculation of the fatigue crack formation and growth accelerated loadspectra, the one corresponding to the bigger damage is determined as the fatigue accelerated testload spectrum. Therefore in the test process, the fatigue accelerated test spectrum may be appliedtill fatigue failure, the engineering fatigue crack length of full-scale structure need not beinspected, and the fatigue crack formation accelerated load spectrum need not be transferred intothe fatigue crack growth accelerated load spectrum. Finally, it is verified by tests of two kinds ofspecimens that the damages of the specimens caused by the accelerated load spectra are near tothose by the actual load spectra; namely, the tested life of actual load spectra is similar to thatof accelerated load spectra. But the test time of accelerated load spectra is shortened by aboutthree-quarters that of actual load spectra. From these tests, it is also found that the fatigueaccelerated test spectrum has an advantage over FALSTAFF spectra.

关键词： ternary-waves actual load-time history accelerated load spectra equivalent damage calculation main wave secondary wave carrier wave

NON-EQUILIBRIUM SOLUTE SEGREGATION TO AUSTENITIC GRAIN BOUNDARY IN FERRUM-NICKLE ALLOY

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Acta Metallurgica Sinica(English Letters) 2001年第6期14卷 525-531页

作者： P. Wu, D.Y. Yu and X.L. He (Department of Material Physics, university of science & Technology beijing, beijing {4. china) Dept. of Mat. Phys. Univ. of Sci. and Technol. Beijing Beijing 100083 China

The development of non-equilibrium segregation of boron at grain boundaries in Fe-4.0%Ni alloy during continuous cooling process was experimentally observed with boron Particle Tracking Autoradiography (PTA) and Transmission Electron Microscopy (TEM,). The samples with 10ppm boron were cooled at 2℃/s to 104., 980, 920, 860, 780 and 64.℃ respectively after pre-heat treatment of 1150℃ for 15mm with a Gleeble-1500 heat simulating machine, then water quenched to room temperature. The width of segregation layer and boron depletion zone, rich factor and other parameters were measured by a special image analysis system. The experimental results of PTA show that the grain boundary segregation of boron during cooling process is a dynamic process and the development of the non-equilibrium segregation experiences three stages: first increases rapidly from 1150 to 104.℃, then gently from 104. to 860℃, and rapidly again from 860℃ to 64.℃. The width of boron depletion zone increases from about 11μm at 104.℃ to 26μm at 64.℃. TEM observation shows that boron precipitates exist at grain boundaries when the samples are cooled to below 860℃. The experimental phenomena are briefly discussed.

关键词： boron grain boundary non-equilibrium segregation