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Journal of Rare Earths 2018年第6期36卷 594-602页

作者： Ning Liu Jingyu wang fengying wang Jun Liu School of Environment and Safety Engineering North University of ChinaTaiyuan 030051China Key Laboratory of Coal Science and Technology Ministry of Education and Shanxi ProvinceTaiyuan University of TechnologyTaiyuan 030024China

A superior Ce-Ta-Sb composite oxide catalyst prepared using homogeneous precipitation method exhibited excellent deNOx efficiency and nearly 100% Nselectivity with broad operation temperature window and better resistance to higher space velocity, meanwhile strong resistance to HO and SO. This catalyst was systematically characterized using XRD, Nadsorption, SEM, TEM, XPS, ESR, Raman, H-TPR,NH3-TPD and in situ DRIFTS. There exists a synergistic effect between Ce, Ta and Sb species. It is further indicated that the prominent deNOx performance of the Ce3 Ta3 SbOx catalyst is attributed to the elevated Ce3+ concentrations, abundant active surface oxygen species, as well as surface acidity and reducibility,which is closely linked with the synergistic effect between Ce, Sb and Ta species. Results from DRIFTS reveal that the reaction mechanism of surface-adsorbed NH3 and NOspecies is linked to temperature,the L-H mechanism mainly occurs at low temperature(300 ℃). Overall,these findings indicate that Ce3 Ta3 SbOx is promising for NOpractical abatement.

关键词： Ce-Ta-Sb mixed oxides Homogeneous precipitation method NH_3-SCR Synergistic effect NO_x adsorbed species Rare earths

The Properties of the Sintered Copper Powder Liner

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Journal of Wuhan University of Technology(Materials Science) 2014年第2期29卷 269-272页

作者：段能全 GAO Yonghong wang Junyuan DU Wenhua wang fengying School of Mechanical and Power Engineering North University of China School of Chemical Engineering and Environment North University of China

In order to study the properties of sintered copper powder shaped charge liner, the copper powder, whose particle size was below 20 μm, was chosen as the main material. The mixed powders were directly pressed into the desired shape of the shaped charge liner by the top direct-pressure way. The microscopic morphology of the spinning shaped charge liner, the sintered and non-sintered powder liners, and the particle properties of the copper powder were studied with scanning electron microscopy. The expe^mental results showed that the irregular copper powder could get together effectively and sintering could improve the compactness of the powder liner effectively. The wall thickness and density of the non-sintered and sintered liner were also tested, and it shows that sintering causes the wall thickness thinned and the density improved. The penetration depths of non-sintered powder liner, sintered powder liner and the spinning copper plate liner were tested with different standoff respectively, showing that the penetration properties of sintered powder liner are well.

关键词： irregular copper powder powder shaped charge liner sintering penetration

Stepping-quenching-partitioning treatment of 20SiMn2MoVA steel and effects of carbon and carbide forming elements

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Science China(Technological Sciences) 2012年第7期55卷 1838-1843页

作者： ZHU YueFeng wang fengying ZHOU HuiHua wang Guan JIANG BoZhi Key Laboratory for Advanced Materials Processing Technology Ministry of Education of China Department of Mechanical EngineeringTsinghua UniversityBeijing 100084China Department of Materials Science and Engineering Tsinghua UniversityBeijing 100084China

A novel heat treatment process,stepping quenching and partitioning(S-Q-P),has been developed to manipulate microstructure and mechanical properties of *** on incomplete partitioning of carbon from martensite to austenite,volume fraction and distribution of the retained austenite resulting from the following quenching of the steels could be effectively controlled,and then the synthesized mechanical properties of the steels would be *** this paper,20SiMn2MoVA steel was treated with conventional quenching-tempering(Q-T),currently prevailing quenching-partitioning(Q-P) and S-Q-P processes,*** results indicated that the volume fraction of the retained austenite of the steel treated by Q-P and S-Q-P processes increased significantly that resulted in the increase of ductility and decrease of *** product of strength and ductility of the steel treated by S-Q-P process reached 23.7GPa%,that was increased by about 13% and 7% compared with that after Q-T and Q-P processes,*** with the great improvement of the synthesized mechanical property obtained by S-Q-P process with another steel 35SiMn,there would be some factors that deteriorated the effect of S-Q-P process on 20SiMn2MoVA *** was found by microstructural testing that the carbide forming elements V and Mo in the steel led to precipitation of carbides during partitioning period and lack of carbon in *** a result,less austenite would remain after final quenching and mechanical properties of the steel would be *** results would be beneficial for understanding the principle of S-Q-P process and improving the design of the S-Q-P steel compositions.

关键词： 20SiMn2MoVA heat treatment microstructure mechanical property carbide

A novel microstructural design and heat treatment technique based on gradient control of carbon partitioning between austenite and martensite for high strength steels

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Science China(Technological Sciences) 2013年第8期56卷 1847-1857页

作者： wang fengying ZHU YueFeng ZHOU HuiHua JIANG BoZhi wang Guan Key Laboratory for Advanced Materials Processing Technology Ministry of EducationChinaDepartment of Mechanical EngineeringTsinghua University Department of Materials Science and Engineering Tsinghua University

Based on gradient control of carbon partitioning between martensite and austenite during heat treatment of steels,a stepping-quenching-partitioning(S-Q-P) process is developed for high strength *** S-Q-P process involves several quenching processes at progressively lower temperatures between martensite-start(Ms) and martensite-finish(Mf) temperatures,each followed by a partitioning treatment at either the initial quenching temperature or above that temperature.A novel microstructure is designed based on the S-Q-P *** and distributions of retained austenite and high-carbon martensite surrounded by martensite laths can be manipulated by the partitioning duration and temperature,and quenching temperature of the S-Q-P *** element Si is employed in the S-Q-P steel to suppress formation of carbides and create suitable amount of retained austenite.A steel of 0.39C-1.22Mn-1.12Si-0.23Cr(wt.%) treated by the S-Q-P process is endowed with some special microstructural characteristics:some strips of retained austenite located at edges of martensite blocks with high density of dislocations and between martensite laths,some small blocks of twinned martensites distributed among bundles of the low-carbon martensite *** mechanical properties of the medium carbon steel after the S-Q-P process can reach ultimate tensile strength(Rm) of 1240 MPa,total elongation(EI) of 25%,and product of strength and ductility(PSD) of 31.2 GPa% that are much more improved than those after the conventional quenching-tempering(Q-T) and currently prevailing quenching-partitioning(Q-P) *** PSD of the tested steel after the S-Q-P process increases by 67% and 32% as compared with those after the Q-T and Q-P processes,respectively.

关键词： steel heat treatment carbon diffusion microstructure mechanical property

Mapping carbon distribution in 35SiMn steel by energy-filtered transmission electron microscopy

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Science China(Technological Sciences) 2012年第7期55卷 1833-1837页

作者： ZHONG XiaoYan ZHOU HuiHua wang fengying ZHU YueFeng Department of Materials Science and Engineering Beijing National Center for Electron MicroscopyLaboratory of Advanced MaterialsTsinghua UniversityBeijing 100084China Key Laboratory for Advanced Materials Processing Technology Ministry of Education&Department of Mechanical EngineeringTsinghua UniversityBeijing 100084China

In this study,the three-windows method,the jump-ratio method and the R-map method in energy-filtered transmission electron microscopy(EFTEM) have been applied to mapping carbon distribution in 35SiMn steel after a quenching-partitioning *** carbon contamination is successfully suppressed by using EFTEM and plasma-cleaning TEM *** to the three-windows method and the jump-ratio method,the R-map method provides carbon distribution with less noises,and is insensitive to changes in sample *** have demonstrated that the R-map method is a better way for carbon mapping in middle-carbon steel without the influence of carbon contamination.

关键词： carbon mapping distribution steel energy-filtered transmission electron microscopy

Field emission properties of amorphous GaN ultrathin films fabricated by pulsed laser deposition

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Science in China(Series F) 2009年第10期52卷 1947-1952页

作者： wang fengying wang RuZhi ZHAO Wei SONG XueMei wang Bo YAN Hui Laboratory of Thin Film College of Materials Science and Engineering Beijing University of Technology Beijing 100124 China

Amorphous gallium nitride （a-GaN） films with thicknesses of 5 and 300 nm are deposited on n-Si （100） substrates by pulsed laser deposition （PLD）, and their field emission （FE） properties are studied. It shows that compared with thicker （300 nm） a-GaN film, better FE performance is obtained on ultrathin （5 nm） a-GaN film with a threshold field of 0.78 V/μm, which is the lowest value ever reported. Furthermore, the current density reaches 42 mA/cm2 when the applied field is 3.72 V/μm. These experimental results unambiguously confirm Binh＇s theoretical analysis （Binh et al. Phys Rev Lett, 2000, 85（4）： 864-867） that the FE performance would be prominently enhanced with the coating of an ultra-thin wide band-gap semiconductor film.

关键词： field emission amorphous gallium nitride (a-GaN) pulsed laser deposition (PLD) work function

Nanodiamond films deposited at moderate temperature on pure titanium substrate pretreated by ultrasonic scratching in diamond powder suspension

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Journal of University of Science and Technology Beijing 2006年第6期13卷 542-545页

作者： Syed Jawid Askari Fanxiu Lv Akhtar Farid fengying wang Qi He Zuyuan Zhou Materials Science and Engineering School University of Science and Technology Beijing Beijing 100083 China ES Department PNEC PNS Jauhar National University of Sciences ＆ Technology Karachi-75350 Pakistan

Nanocrystalline diamond （NCD） film deposition on pure titanium and Ti alloys is extraordinarily difficult because of the high diffusion coefficient of carbon in Ti, the large mismatch in their thermal expansion coefficients, the complex nature of the interlayer formed during diamond deposition, and the difficulty to achieve very high nucleation density. In this investigation, NCD films were successfully deposited on pure Ti substrate by using a novel substrate pretreatment of ultrasonic scratching in a diamond powder-ethanol suspension and by a two-step process at moderate temperature. It was shown that by scratching with a 30-μm diamond suspension for 1 h, followed by a 10-h diamond deposition, a continuous NCD film was obtained with an average grain size of about 200 nm. Detailed experimental results on the preparation, characterization, and successful deposition of the NCD films on Ti were discussed.

关键词： nanocrystalline diamond film pure Ti substrate nucleation enhancement moderate temperature

Case Report of an Endodermal Sinus Vaginal Tumor in an Infant Girl

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Chinese Journal of Clinical Oncology 2007年第1期4卷 71-72页

作者： Chunyu Sun YUqiu Cui Hongfei Li fengying wang Department of Pathology Fushun No. 3 Hospital Fushun 113004 China

Case Report An female infant patient, aged 8 months old, suffered from irregular colporrhagia for a period of 1 month after which she was taken to our hospital on 30th April, 2003. A pelvic CT examination displayed a 6.5 cm×3.0 cm shadow of a soft-tissue tumor growing longitudinally in her supravaginal uterine area （Fig. 1）. The density of the shadow was uneven, in which there were irregular low-density loci, an indication of a compression of the colon and bladder and a diffuse boundary between the posterior wall of the urinary bladder and tumor. No abnormalities were found in either kidney or ovary, the liver or gall bladder. Also no obvious lesions were seen on the chest X-ray film, and routine blood and urine laboratory examinations were normal.

关键词： endodermal sinus tumor a-fetoprotein diagnosis.

Close Neighbors Plus Relatives──An unforgettable Trip to the Philippines

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International Understanding 1996年第2期 13-14页

作者： $$$$wang fengying

At the invitation of *** Center of the Philip-pine University,a five-mem-berCAFIU delegation visited the *** host high-ly regarded our visit,gave us a W arm and courteous ***.

关键词： Plus An unforgettable Trip to the Philippines Close Neighbors Plus Relatives

Bayesian Analysis of Small Multi-frequency Investment of Agricultural Products

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Asian Agricultural Research 2015年第12期7卷 9-11页

作者： fengying wang School of Information Beijing Wuzi University

The risk decision of small multi-frequency investment mode of agricultural products is studied based on Bayesian method. This method can take advantage of new market information reasonably,analyze the posterior risk and quantify the decision risk. It provides a scientific way for the risk decision of agricultural enterprises and is advantageous to enhancing the benefit of project.

关键词： Agricultural products Bayesian decision Posterior information Expected loss